Developer accommodating unit, process cartridge, and electrophotographic image forming apparatus

[0001] This application is a continuation application of International Application No. PCT/JP2012/068528, filed on Jul. 13, 2012, and published as PCT Publication No. 2013/008953 on Jan. 17, 2013.

[0002] The present invention relates to a developer accommodating unit for accommodating a developer for image formation, a detachably mountable cartridge including the developer accommodating unit, and an electrophotographic image forming apparatus including this cartridge.

[0003] Here, the electrophotographic image forming apparatus forms an image on a recording material (medium) by using, e.g., an electrophotographic image forming process and may include, e.g., an electrophotographic copying machine, an electrophotographic printer (such as an LED printer or a laser beam printer), an electrophotographic facsimile machine, and the like.

[0004] Further, the cartridge refers to a cartridge including at least a developing means and the developing device which are integrally constituted to be made detachably mountable to an image forming apparatus main assembly and a cartridge including the developing device and at least an electrophotographic photosensitive member which are integrally constituted to be made detachably mountable to the image forming apparatus main assembly.

[0005] Further, the developer accommodating unit is accommodated in the image forming apparatus or the cartridge. The developer accommodating unit is at least provided with a flexible container for accommodating the developer.

[0006] In a conventional electrophotographic image forming apparatus using the electrophotographic image forming process, a process cartridge type in which an electrophotographic photosensitive member and process means actable on the photosensitive member are integrally assembled into a cartridge and this cartridge is detachably mountable to a main assembly of the electrophotographic image forming apparatus is employed.

[0007] In such a process cartridge, as shown in FIG. 35, an opening provided to a developer accommodating frame 31 for accommodating the developer (toner, carrier, etc.) is sealed with a sealing member. Further, a type in which a bonding portion 33 of a toner seal 32 which is the sealing member is pulled and peeled during use, thus unsealing the opening to enable supply of the developer has been widely employed (Japanese Laid-Open Patent Application (JP-A) Hei 4-66900).

[0008] Further, against a problem such that the developer is scattered in the process cartridge in a developer filling step during manufacturing of the process cartridge, a constitution in which a deformable inner container is used has been proposed (JP-A Hei 4-66980).

[0009] However, in the above-described conventional example, there was the following problem

[0010] In the above-described JP-A Hei 4-69980, for the purposes of improving operativity of supply of the developer and reducing a cost of a developer supplying device by scattering prevention in the process cartridge, a method of accommodating the developer in a deformable developer accommodating member is described.

[0011] However, in the case where the developer is accommodated in the deformable developer accommodating member, the opening of the deformable developer accommodating member is pulled together with the toner seal during unsealing, so that it becomes difficult to effect the unsealing.

[0012] An object of present invention is in the developer unit using the flexible container for accommodating the developer, to improve an unsealing characteristic of the sealing member for sealing the opening of the flexible container.

[0013] In order to accomplish the above object, the present invention is characterized by a developer accommodating unit for accommodating a developer for image formation, comprising: a flexible container including a developer accommodating portion for accommodating the developer and an opening for permitting discharge of the developer; a sealing member for sealing the opening; an unsealing member for moving the sealing member to unseal the opening; and a frame which accommodates the flexible container, the sealing member and the unsealing member and which includes a fixing portion for fixing the flexible container, wherein said flexible container includes a superposed multi-layer sheet structure portion for forming the developer accommodating portion, and wherein a fixed portion fixed to the fixing portion is provided at the multi-layer sheet structure portion, and an interlayer bonding portion between the superposed layers is provided between the fixed portion of the multi-layer sheet structure portion and the developer accommodating portion.

[0014] According to the present invention, in the developer accommodating unit using the flexible container for accommodating the developer, it is possible to improve the unsealing characteristic of the sealing member for sealing the opening of the flexible container.

[0050] Hereinbelow, with reference to the drawings, suitable embodiments of the present invention will be exemplarily described in detail. However, dimensions, materials, shapes and relative arrangement of constituent elements described in the following embodiments should be appropriately changed depending on constitutions and various conditions of apparatuses (devices) to which the present invention is applied. Accordingly, unless otherwise specified, the scope of the present invention is not intended to be limited to only them.

[0051] In the following description, a developer accommodating container refers to at least a flexibility container and a sealing member for sealing an opening, provided to the flexible container, for permitting discharge of a developer. The developer accommodating container before the developer is accommodated therein is referred to as a developer accommodating container 37 for accommodating the developer. The developer accommodating container which accommodates the developer and which is provided with an unsealing member for unsealing the sealing member is referred to as a developer accommodating container 30 including the unsealing member. The developer accommodating container which accommodates the developer and which is not provided with the sealing member is referred to as a developer accommodating container 26 accommodating the developer.

[0052] Incidentally, for simplification, these developer accommodating containers will be described as the developer accommodating container 37, the developer accommodating container 30 and the developer accommodating container 26 by using different reference numerals.

[0053] A developer accommodating unit includes at least the developer accommodating container and a frame for accommodating the developer accommodating container.

[0054] FIG. 1 illustrates a principal sectional view of a process cartridge including the developer accommodating unit to which the present invention is applicable, and FIG. 2 illustrates a principal sectional view of an image forming apparatus to which the present invention is applicable.

<Summary of Structure of Process Cartridge>

[0055] The process cartridge includes an image bearing member (electrophotographic photosensitive member) and process means actable on the image bearing member. Here, as the process means, there are, e.g., a charging means for electrically charging a surface of the image bearing member, a developing device for forming an image on the image bearing member, and a cleaning means for removing a developer (containing toner, carrier, etc.) remaining on the image bearing member surface.

[0056] The process cartridge A in this embodiment includes, as shown in FIG. 1, includes a photosensitive (member) drum 11 as the image bearing member and includes, at a periphery of the photosensitive drum 11, a charging roller 12 as the charging means and a cleaner unit 24 including a cleaning blade 14, having elasticity, as the cleaning means. Further, the process cartridge A includes a developing device 38 including a first frame 17 and a second frame 18. The process cartridge A integrally includes the cleaner unit 24 and the developing device 38, and is constituted so as to be detachably mountable to an image forming apparatus main assembly B as shown in FIG. 2. The developing device 38 includes a developing roller 13 as the developing means, a developing blade 15, a developer supplying roller 23, and a developer accommodating container 26, for accommodating the developer, in which the developer is accommodated. The developing roller 13 and the developing blade are supported by the first frame 17.

<Summary of Structure of Electrophotographic Image Forming Apparatus>

[0057] The process cartridge A is mounted in the image forming apparatus main assembly B as shown in FIG. 2 and is used for image formation. In the image formation, a sheet S is fed by a feeding roller 7 from a sheet cassette 6 mounted at a lower portion of the apparatus, and in synchronism with this sheet feeding, the photosensitive drum 11 is selectively exposed to light by an exposure device 8 to form a latent image. The developer is supplied to the developing roller 13 (developer carrying member) by the sponge-like developer supplying roller 23 and is carried in a thin layer on the surface of the developing roller 13. By applying a developing bias to the developing roller 13, the developer is supplied depending on the latent image and thus the latent image is developed into a developer image. Thia (developer) image is transferred onto the fed sheet S by bias voltage application to a transfer roller 9. The sheet S is conveyed to a fixing device 10 to be subjected to image fixing, and the sheet S is discharged by a discharging roller 1 to a discharge portion 3 at an upper portion of the apparatus.

<Summary of Structure of Developer Accommodating Unit>

[0058] Next, a structure of a developer accommodating unit 25 will be described with reference to FIG. 3, FIG. 4, (a) of FIG. 7 and FIG. 20. Here, FIG. 3 is a perspective view of the developer accommodating container 30 from cross section, FIG. 4 is a sectional view of the developing device 38, FIG. 7 is a detailed sectional view in the neighborhood of the discharging portion 35 for permitting discharge of the developer from a developer bag 16 as a flexible container, and FIG. 20 is a sectional view of the developer accommodating container 26 from cross section. Incidentally, the sectional views are a plane passing through an unsealing member 20, openings 35a and fixing portions 16d and 16e. Further, the sectional views are a plane perpendicular to a rotational axis of the unsealing member 20.

(Developer Accommodating Unit)

[0059] The developer accommodating unit 25 is, as shown in FIG. 4, constituted from the developer accommodating container 30, the developing roller 13, the developing blade 15, the developer supplying roller 23, and the first frame 17 and the second frame 18 which support these members. A combination of the first frame and the second frame is a frame which accommodates the developer accommodating container 30.

[0060] Incidentally, in this embodiment, the developer accommodating unit 25 is the same as the developing device 38. This is because the developer accommodating unit 25 includes the developing roller 13, the developing blade 15 and the developer supplying roller 23. However, the developing roller 13, the developing blade 15 and the developer supplying roller 23 may also be supported by a frame separately from the developer accommodating unit 25 and thus may be separated from the developer accommodating unit 25. In this case, the developing device 38 is constituted by the developer accommodating unit 25, the developing roller 13, the developing blade 15 and the developer supplying roller 23 (not shown).

(Developer Accommodating Container Including Unsealing Member)

[0061] The developer accommodating container 30 including the unsealing member is constituted by an unsealing member 20 and the developer accommodating container 26 as shown in FIG. 3 and FIG. 4.

[0062] The unsealing member 20 includes an engaging portion 20b to be engaged with a sealing member 19, and by engaging a portion-to-be-engaged 19b of the developer accommodating container 26 with the engaging portion 20b, the developer accommodating container 30 including the unsealing member is constituted.

(Developer Accommodating Container in which Developer is Accommodated)

[0063] As shown in (c) of FIG. 29, the developer accommodating container 26 is constituted from the developer, a developer bag 16 and the sealing member 19. Here, the developer is powder.

[0064] The developer bag 16 of the developer accommodating container 26 is sealed with the sealing member 19 at the plurality of openings 35a for permitting the discharge of the developer and includes a bonding portion 39a which seals a filling opening (injection port) for permitting filling (entrance) of the developer. Thus, the respective openings 35a and the filling opening 39 of the developer accommodating container 26 in which the developer is accommodated are sealed and therefore the accommodated developer is not leaked out to the outside, so that the developer accommodating container 26 can be treated as a single unit. Further, the sealing member 19 includes holes as the portions-to-be-engaged 19b to be engaged with the unsealing member 20, thus being engageable with the unsealing member 20.

(Developer Accommodating Container for Accommodating Developer)

[0065] As shown in (a) of FIG. 29, the developer accommodating container 37 for accommodating the developer is constituted from the developer bag 16 and the sealing member 19 for sealing the plurality of openings 35a for permitting the discharge of the developer and for exposing the openings 35a by being moved. Here, the developer bag 16 of the developer accommodating container 37 for accommodating the developer includes the filling opening 39 for permitting the filling of the developer and the openings 35a for permitting the discharge of the developer. The openings 35a are provided in a plurality of positions of the developer bag 16.

[0066] Here, in the developer accommodating container 37 for accommodating the developer, the developer is not filled as yet, and the developer accommodating container 31 is in a state in which the filling opening 39 for permitting the filling of the developer is open.

(Filling and Developer Accommodating Container)

[0067] Here, a relation between the developer accommodating container 37 for accommodating the developer and the developer accommodating container 26 in which the developer it accommodated will be described.

[0068] First, as shown in (a) of FIG. 23, the developer accommodating container 37 for accommodating the developer is not filled with the developer and is provided with the filling opening 39 for permitting the filling of the developer.

[0069] Next, as shown in (b) of FIG. 29, the developer is filled from the filling opening 39, for permitting the filling of the developer, of the developer accommodating container 37 for accommodating the developer. Further, by flexibility of the developer bag 16, the filling opening 39 for permitting the filling of the developer is deformable correspondingly to a filling device and thus the filling of the developer is facilitated without causing scattering of the developer. At the time of the filling, a known auger type filling device is used but another method having a similar function may also be used.

[0070] Then, as shown in (c) of FIG. 29, the filling opening 39 for permitting the filling of the developer is bonded and sealed. The bonding of the bonding portion 39a of the opening for permitting the filling of the developer is made by ultrasonic bonding in this embodiment but may also be made by other bonding methods using heat, a laser and the like.

[0071] Then, when the bonding of the bonding portion 39a of the opening for permitting the filling is completed, the developer is filled, so that the developer accommodating container 26 in which the developer is accommodated is provided.

[0072] Incidentally, a position and a size of the filling opening 39 for permitting the filling may appropriately by disposed correspondingly to shapes and the like of the filling device of the developer and the process cartridge A.

(Effect of Incorporating Developer Bag in Developing Device)

[0073] By forming the developer-accommodated developer accommodating container 26 in a bag shape, the developer can be treated as a unit. For that reason, a developer filling step can be separated from a main assembling step (manufacturing line) of the process cartridge A. By this, the developer is prevented from being scattered in the main assembling step (manufacturing line) of the process cartridge A, so that maintenance such as cleaning of the manufacturing line can be reduced. By the prevention of the scattering of the developer during the assembling step, it is possible to omit a cleaning stop of the process cartridge A to be performed after the filling of the developer.

[0074] Further, also in the filling step of the developer bag 16, the developer bag 16 has flexibility, and the filling opening 39 for permitting the filling is also soft and therefore can be easily sealed with less scattering.

[0075] Further, the developer accommodating container 26 in which the developer is accommodated has flexibility and therefore can be assembled while following a shape of the frame.

[0076] Further, in the filling step, the developer accommodating container 37 has flexibility and therefore deforms its cross section to increase its volume in which the developer can be filled, so that a filling amount can be increased during the filling.

[0077] Further, the developer accommodating container 37 before the developer filling has flexibility and thus can be made small (thin), so that a storing space during storage before the filling can be made small compared with the frame which is a resinous structure.

<Structure of Developer Bag>

[0078] As shown in FIG. 3 and FIG. 4, the developer bag 16 accommodates the developer therein and has a bag-Like shape which is deformable, and is provided with the plurality of openings 35a at the discharging portion 35, for permitting the discharge of the accommodated developer.

[0079] Further, the developer bag 16 includes developer bag fixing portions 16d and 16e as portions-to-be-fixed to be fixed to fixing portions of the first frame 17 and the second frame 18.

(Material and Air Permeability of Developer Bag)

[0080] FIG. 28 includes sectional views for illustrating the developer accommodating container 26. As shown in (a) and (b) of FIG. 28, the developer bag 16 is constituted by bonding a sheet 16u which includes the discharging portion 35 and does not have air permeability and a sheet 16s which has the air permeability and which is an air permeable portion to each other at a bonding-together portion 16i. The developer bag 16 includes a developer accommodating portion formed by the sheets 16u, 16s as a sheet member.

[0081] Here, a degree of the air permeability of the air permeable portion 16s may appropriately be selected so that the developer is prevented from leaking out of the developer bag 16 based on a balance with a size of the developer (particle size of powder) to be accommodated.

[0082] As a material for the air permeable portion 16s, a nonwoven fabric or the like formed of polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP) or the like in a thickness of 0.03-0.15 mm is preferred. Further, even when the material for the air permeable portion 16s is not the nonwoven fabric, a material having minute holes which are smaller than the powder such as the developer may also be used.

[0083] Further, with respect to arrangement of the air permeable portion, in this embodiment, as shown in FIG. 3 and FIG. 28, the air permeable portion 16s is disposed over the entire region of the developer bag 16 with respect to a longitudinal direction in the second frame 18 side. Incidentally, as shown in (c) and (d) of FIG. 28, the air permeable portion 16s may also constitute the entire developer bag 16 by being bonded together at the bonding-together portion 16i.

[0084] Incidentally, as the material for the developer bag 16 other than the air permeable portion 16s, a material having flexibility so as to improve efficiency during the discharge of the developer described later may preferably be used. Further, the material for the air permeable portion 16s may also have flexibility.

(Effect of Developer Bag Having Air Permeability)

[0085] Thus, the reason why the air permeability is imparted to the developer bag 16 is that the developer bag 16 can meet states during manufacturing, during transportation until a user uses the cartridge A, and during storage. First, the reason for the state during the manufacturing is that the developer bag 16 is made deformable and reducible in order to facilitate assembling of the developer bag 16 with the frames 17 and 18. In the case where the developer bag 16 is not provided with the air permeability portion, the size thereof cannot be changed from that in a state in which the developer bag 16 is filled with the developer (state in which the bag is closed) and therefore the developer bag 16 is not readily deformed. For that reason, it takes time to assembling and steps are complicated. Therefore, when the air permeability is imparted to at least a part of the developer bag 16, the size of the developer bag 16 can be changed from that in the state in which the developer bag 16 is filled with the developer and then is closed, thus facilitating the assembling.

[0086] Next, the reason for the states during the transportation and during the storage is that the developer bag 16 can meet a change in different air pressure during the transportation and during the storage of the process cartridge A. The difference in air pressure between the inside and outside of the developer bag 16 is generated in the case where the developer bag 16 is in a lower air-pressure environment during the transportation or the like than during the manufacturing or in the case where the developer bag 16 is stored at a higher temperature than during the manufacturing. For that reason, by expansion of the developer bag 16, there is a fear that parts contacting the developer bag 16 are deformed or broken. There is a need, for that purpose, to control the air pressure and the temperature during the transportation and during the storage, so that facilitates and a cost are needed. However, problems caused due to the difference in air pressure between the inside and outside of the developer bag 16 can be solved by partly imparting the air permeability to the developer bag 16.

[0087] Further, in the case where the nonwoven fabric is provided with the discharging portion 35 and a bonding portion 22 at a periphery of the discharging portion 35, there is a fear that fibers of the nonwoven fabric fall out with peeling of the sealing member 19 during unsealing and then enter the developer to adversely affect the image. For that reason, by providing the discharging portion 35 to the sheet 16u different from the sheet 16u having the air permeability, the above-described falling-out of the fibers from the nonwoven fabric is prevented.

[0088] Further, a filling density can be increased by filling the developer while effecting deaeration from the air permeable portion 16s.

(Structure of Discharging Portion of Developer Bag)

[0089] As shown in FIG. 3 and FIG. 10, the developer bag 16 includes the developer discharging portion 35 consisting of the plurality of openings 35a for permitting the discharge of the inside developer and the connecting portion 35b defining the plurality of openings 35a. Further, the discharging portion 35 is continuously surrounded at its periphery by the bonding portion 22 to be unsealably bonded, so that the developer accommodated in the developer bag 16 is sealed with the sealing member 19.

(Structure of Bonding Portion of Developer Bag)

[0090] The bonding portion 22 has a rectangular shape surrounded by two lines extending in a long direction (arrow F direction) and two lines extending in a short direction (arrow E direction), and therefore the bonding portion 22 enables the sealing of the discharging portion 35.

[0091] Here, of the two lines of the bonding portion 22 welded with respect to the long direction (arrow F direction), a bonding portion which is first unsealed is referred to as a first bonding portion 22a and a bonding portion which is unsealed later is referred to as a second bonding portion 22b. In this embodiment, in the case where the bonding portion 22 is viewed along the surface of the sealing member 19, the bonding portion in a side closer to a fold(ed)-back portion 19d (or portion-to-be-engaged 19b) described later is the first bonding portion 22a. Further, the bonding portion opposing the first bonding portion 22a via the opening 35a is the second bonding portion 22b. Further, a bonding portion with respect to a widthwise direction (arrow E direction) is a widthwise (short) bonding portion 22c.

[0092] In this embodiment, an unsealing direction is the arrow E direction. The unsealing direction is defined as follows. In the case where the unsealing is effected by moving the sealing member 19, of the first bonding portion 22a and the second bonding portion 22b opposing to each other via the opening 35a, the first bonding portion 22a is first unsealed (peeled). Thus, a direction directed from the first bonding portion 22a to be first unsealed toward the second bonding portion 22b is the unsealing direction (arrow E direction).

[0093] Incidentally, when the sealing member 19 is unsealed (peeled) from the developer bag 16 in the arrow E direction, when viewed microscopically, the peeling progresses also in the arrow F direction in some cases due to the deformation of the developer bag 16 by an unsealing force also in the first bonding portion 22a and the second bonding portion 22b. However, the unsealing direction in this embodiment does not refer to such a microscopic unsealing direction.

(Arrangement of Openings of Developer Bag)

[0094] Next, arrangement of the openings 35a will be described with reference to FIG. 10, FIG. 11 and FIG. 29. The movement direction of the sealing member 19 (the direction of the sealing member 19 pulled by the unsealing member 20) for sealing the openings 35a and for exposing the openings 35a by being moved is the arrow D direction. By the movement of the sealing member 19, the exposure of the openings 35a progresses in the unsealing direction (arrow E direction). In the following, the movement direction of the sealing member 19 is the arrow D direction.

[0095] The plurality of openings 35a and the plurality of connecting portions 35b are disposed at different positions in the direction (arrow F direction) perpendicular to the unsealing direction (arrow E direction). Further, the sealing member 19 is configured to be wound up by rotating the unsealing member 20 but the above-described arrow F direction is the same direction as an axis (axial line) of the rotation shaft of the unsealing member 20.

[0096] Here, the reason why the rotational axis direction of the developing roller 13 and the arranged direction (arrow F direction) of the plurality of openings 35a are made equal is that the developer is easily supplied, during the discharge thereof, to the developing roller 13 over the entire longitudinal direction without being localized.

[0097] Here, the plurality of openings 35a are disposed at the different positions in the arrow F direction and therefore the discharging portion 35 is long in the arrow F direction and is short in the arrow E direction. That is, with respect to the arrow F direction, a distance from an and to another end of the plurality of openings 35a is longer than that with respect to the arrow E direction.

[0098] Thus, the discharging portion 35 where the plurality of openings 35a are disposed at the different positions in the direction (arrow F direction) perpendicular to the unsealing direction (arrow E direction) is long in the arrow F direction and is snort in the arrow E direction. For that reason, the distance required for the unsealing can be made shorter than that required for the unsealing in the long direction (arrow F direction) and therefore a time required for the unsealing can also be made short.

[0099] Further, a constitution in which the sealing member 19 for covering the discharging portion 35 is wound up by the unsealing member 20 is employed. The rotational axis direction of the unsealing member 20 and the direction (arrow D direction) substantially perpendicular to the unsealing direction (arrow E direction) are made equal, so that winding distance and time of the sealing member 19 can be shortened.

(Shape and Direction of Openings of Developer Bag)

[0100] Each of the plurality of openings 35a in First Embodiment has a circular shape. When a discharging property is taken into consideration, an area of the openings 35a may preferably be large. Further, the connecting portions 35b defining the openings 35a may preferably be large (thick) in order to enhance the strength of the developer bag 16. Therefore, the area of the openings 35a and the area of the connecting portions 35b are required to achieve a balance in view of a material and a thickness of the discharging portion 35 and a force relationship with peeling strength during the unsealing described later and may be appropriately selected. Further, the shape of the openings 35a may also be, in addition to the circular shape, a polygonal shape such as a rectangular shape, an elongated circular shape as shown in FIG. 12 in Second Embodiment described later, and the like shape.

[0101] Incidentally, the arrangement of the openings 35a may only be required to be disposed at the different positions with respect to the direction (arrow F direction) perpendicular to the unsealing direction (arrow E direction). Even when the openings 35a overlap with each other as shown in (c) of FIG. 27, or do not overlap with each other as shown in (d) of FIG. 27, there is an effect of the connecting portions 35b described later.

[0102] Further, the direction of the openings 35a may preferably be such that the developer accommodated in the developer bag 16 is easily discharged in an attitude during image formation. For that reason, in the attitude during image formation, the openings 35a are disposed so as to be open downward with respect to the gravitational direction. Here, the downward opening of the openings 35a with respect to the gravitational direction refers to that the direction of the openings 35a has a downward component with respect to the gravitational direction.

(Fixing Between Developer Bag and Frame)

[0103] As shown in FIG. 3 and FIG. 4, the developer bag 16 includes the two fixing portions 16d and 16e as portions to-be-fixed, described below. The developer bag 16 is fixed inside the first frame 17 and the second frame 18 by the two fixing portions 16d and 16e.

(First Fixing Portion)

[0104] First, as a first fixing portion, the first fixing portion 16d of the developer bag 16 where a force is received when the sealing member 19 is unsealed from the developer bag 16 as described later is provided. The first fixing portion 16d is provided at a plurality of positions in parallel to the direction (arrow F direction) in which the plurality of openings 35a are arranged. Incidentally, other than the arrangement at the plurality of positions, the first fixing portion 16d may also be a single fixing portion elongated in parallel to the arrow F direction (not shown).

[0105] Further, as shown in (a) and (b) of FIG. 28, the developer bag 16 includes a multi-layer structure portion 16g where the sheet 16u (or the sheet 16s) as the sheet member for forming the developer bag 16 is superposed by being folded back. Or, as shown in (c) and (d) of FIG. 28, the developer bag 16 includes a multi-layer structure portion 16g where the sheet 16s as the sheet member for forming the developer bag 16 is superposed by being folded back. A folded back direction of the sheet 16u or sheet 16s which constitutes this multi-layer structure portion 16g may also be which direction as shown in FIG. 28.

[0106] Further, at the multi-layer structure portion 16g, a first fixing portion 16d as the fixed portion fixed to the fixing portion 18c of the frame 18 is provided. Further, this first fixing portion 16d is, as shown in FIG. 3, provided along the direction (arrow F direction) perpendicular to a movement direction (arrow D direction) of the sealing member 19. By this, the sealing member 19 receives a force, with respect to the arrow E direction over the arrow F direction perpendicular to the arrow E direction, acting on the developer bag 16 when the sealing member 19 is unsealed, and therefore the unsealing characteristic can be further improved.

[0107] Further, at the multi-layer structure portion 16g, between the bonding-together portion 16i and the fixing portion 16d of the developer bag 16, an interlayer bonding portion 16h for bonding between the above-described sheet 16u or sheet 16s which is bonded together is provided. At the bonding-together portion 16i, the sheet 16u and the sheet 16s are bonded together to form the developer accommodating portion for accommodating the developer.

[0108] Incidentally, in this embodiment, the multi-layer structure portion 16g has a two-layer structure in which the sheet 16u or the sheet 16s is superposed by being folded back once, but is not limited thereto. The multi-layer structure portion 16g may also have a structure of two layers or more which are superposed by folding-back the sheet plural times depending on a value of an unsealing force described later if the respective layers can be bonded therebetween (not shown).

[0109] Further, the position of the first fixing portion 16d is provided in the neighborhood of the openings 35a.

[0110] Further, the first fixing portion 16d of the developer bag 16 is fixed to a first fixing portion 18a of the frame.

[0111] The first fixing portion 16d is a fixing portion necessary for the time of unsealing the developer bag 16, and its action and arrangement will be described later in the description of the unsealing.

(Second Fixing Portion)

[0112] Further, as a second fixing portion, the second fixing portion 16e for preventing movement of the developer bag 16 downward or toward the developing roller 13 and the developer supplying roller 23 is provided. With respect to the second fixing portion 16e, a single layer of the sheet 16d or the sheet 16s, or separate sheets which are bonded together may be used.

[0113] The second fixing portion 16e is provided for the following two reasons. A first reason is that the second fixing portion 16e is prevented from moving downward in the attitude during the image formation. For that reason, the second fixing portion 16e may preferably be disposed at an upper position in the attitude during the image formation.

[0114] Further, a second reason is that the developer bag 16 is prevented from disturbing the image in contact with the developing roller 13 and the developer supplying roller 23 during the image formation. For that reason, the second fixing portion 16e of the developer bag 16 may preferably be provided at a position remote from the developing roller 13 and the developer supplying roller 23. In this embodiment, the second fixing portion 16e of the developer bag 16 is disposed at an upper position remote from the developing roller 13 as shown in FIG. 1.

[0115] Further, the second fixing portion 16e of the developer bag 16 is fixed to a second fixing portion 18b of the frame.

(Fixing Method Between Developer Bag and Frame)

[0116] A fixing method between the developer bag 16 and the second fixing portion 16e will be described by using FIG. 26 and FIG. 4. Parts (a) to (d) of FIG. 27 are illustrations of the fixing portion of the developer accommodating container.

(Fixing Method of First Fixing Portion)

[0117] As a fixing method of the first fixing portion 16d of the developer hag 16, fixing by ultrasonic clamping (caulking) such that a boss of the second frame 18 is passed through the hole of the developer bag 16 to be deformed is used. As shown in (a) of FIG. 26, before fixing, the first fixing portion 18a of the second frame 18 has a cylindrical boss shape, and the first fixing portion 16d of the developer bag 16 has a hole which is open. An assembling step is shown below.

[0118] First, a projected-shaped portion of the first fixing portion 18a of the second frame 18 is passed through the hole of the first fixing portion 16d of the developer bag 16 ((b) of FIG. 26).

[0119] Then, an end of the first fixing portion 18a of the second frame 18 is fused by an ultrasonic clamping tool 36 ((c) of FIG. 26).

[0120] Then, the end of the first fixing portion 18a of the second frame 18 is deformed so that it is larger than the hole of the first fixing portion 16d, so that the developer bag 16 is fixed to the second frame 18 ((d) of FIG. 26).

(Fixing Method of Second Fixing Portion)

[0121] As shown in FIG. 24, a fixing method of the second fixing portion 16e of the developer bag 16 uses clamping by the two frames 17 and 18. Holes are made in the developer bag 16 to constitute the first fixing portion 16e of the developer bag 16, and projections are provided to the second frame 18 to constitute the second fixing portion 18b of the frame.

[0122] Then, an assembling step is shown below. The second fixing portion (projection) 18b of the second frame 18 is passed through the second fixing portion (hole) 16e of the developer bag 16, and then fixing by clamping such that the second fixing portion (hole) 16e of the developer bag is prevented from being disengaged (dropped) from the second fixing portion (projection) 18b is made by the first frame 17.

(Other Fixing Means)

[0123] As other fixing means, other than the above-described ultrasonic clamping, it is also possible to use fixing means other than those using ultrasonic wave. For example, heat clamping using heat, (heat) welding or ultrasonic welding for directly welding the developer bag 16 to the first frame 17 and the second frame 18, bonding using a solvent or an adhesive, insertion of the developer bag 16 between the frames, the heat clamping, the ultrasonic clamping, a screw, or hooking using of holes and projections (such as bosses), and the like means may also be used. Further, the developer bag 16 may also be fixed via a separate member provided between the first or second frame 17 or 18 and the developer bag depending on appropriate design based on relationships in space, arrangement or the like between the developer bag 16 and the first or second frame 17 or 18 (not shown).

<Structure of Sealing Member>

[0124] As shown in FIGS. 3 and 4, the sealing member 19 covers the discharging opening 35 of the developer bag 16 before use of the process cartridge A to seal the developer in the developer bag 16. The sealing member 19 is moved, so that the openings 35a are exposed. The structure of the sealing member 19 has a sheet-like shape including a sealing portion 19a for covering the discharging portion 35 of the developer bag 16, a portion-to-be-engaged 19b to be fixed with the unsealing member 20 described later, and a sealing member connecting portion 19c which connects the sealing portion 19a and the portion-to-be-engaged 19b. This sheet-like sealing member is formed of a laminate material having a sealant layer which exhibits an easy-unsealing property described later, and a base material is polyethylene terephthalate (PET), polyethylene, polypropylene or the like, and a thickness may appropriately be selected from a range of 0.03-0.15 mm.

(Sealing Portion of Sealing Member)

[0125] The sealing portion 19a refers to a region where the sealing member 19 seals the plurality of openings 35a and connecting portions 35b of the developer bag 16. By the sealing portion 19a, the developer is prevented from being leaked from the inside of the developer bag 16 until before use of the process cartridge A.

(Engaging Portion of Sealing Member)

[0126] The sealing member 19 has a free end portion in one end side thereof with respect to the unsealing direction (arrow E direction), and at the free end portion, the portion-to-be-engaged 19b to be engaged with the unsealing member for moving the sealing member is provided. With the portion-to-be-engaged 19b, the unsealing member 20 for moving the sealing member 19 so as to expose the openings 35a is engaged. The unsealing member 20 may also be configured to automatically perform the unsealing by receiving drive (driving force) from the image forming apparatus main assembly B. Or, the unsealing member 20 may also be configured to perform the unsealing by being held and moved by the user. In this embodiment, the unsealing member 20 is a rotation shaft provided in the frame, and the sealing member 19 engaged with the unsealing member 20 is pulled, so that the developer accommodating container 26 accommodating the developer is unsealed.

(Sealing Member Connecting Portion of Sealing Member)

[0127] A portion for connecting the bonding portion 22 and the sealing member engaging portion 19b is the sealing member connecting portion 19c. The sealing member connecting portion 19c is a portion for transmitting a force so as to pull off the bonding portion 22 by receiving the force from the unsealing member 20.

(Folding-Back of Scaling Member Connecting Portion)

[0128] Here, referring to FIG. 12, a plane formed between the first bonding portion 22a and the second bonding portion 22b at the movement of the unsealing is taken as N1. A plane which is perpendicular to the plane N1 and which passes through the first bonding portion 22a is taken as N2. Here, the unsealing member 20 is disposed in the second bonding portion 22b side than the plane N2 passing through the first bonding portion 22a. In other words, the sealing member 19 includes, when it is seen along the surface of the sheet-like sealing member 19, a fold(ed)-back portion 19d where the sealing member 19 is folded back at the portion (connecting portion 19c) between the connecting portion 22 and the portion-to-be-engaged 19b engaged with the unsealing member 20. The fold-back portion 19d may be provided with or not provided with a fold (crease). Here, a folding angle Q of the sealing member 19 may preferably be 90 degrees or less. The folding angle Q is a narrow angle Q between a surface of the bonding portion 22 of the developer bag 16 and a surface along the direction (arrow D direction) in which the sealing member 19 is pulled.

(Fixing of Scaling Member)

[0129] Further, fixing between the scaling member 19 and the unsealing member 20 is, in this embodiment, made by the ultrasonic clamping similarly as in the first fixing portion 16d. Other than the ultrasonic clamping, the fixing may also be made by the (heat) welding, the ultrasonic welding, the bonding, the insertion between the frames, the hooking by a hole and a projection, or the like similarly as the fixing means for the first fixing portion 16d and the second fixing portion 16e.

(Portion Having Easy-Unsealing Property of Sealing Member)

[0130] Next, a method of providing a peeling force of the bonding portion 22 with a desired value will be described. In this embodiment, in order to provide the peeling force with the desired value (herein a minimal force within a range in which the Loner sealing property can be maintained), two methods are principally employed.

[0131] In a first method, a laminate material having a sealant layer for enabling easy unsealing of the sealing member 19 is applied. Further, the first method is a method in which the easy unsealing is enabled at the bonding portion by applying, as the material for the developer bag 16, a sheet material (of, e.g., polyethylene or polypropylene) which is weldable with the sealant layer and which has flexibility. By changing a combination of formulation of the sealant layer with the material to be bonded, the peeling force can be adjusted correspondingly to a desired condition. In this embodiment, a material having a peeling strength of about 3N/15 mm measured by testing methods for hermetically sealed flexible packages of JIS-Z0238 is used.

[0132] A second method is a method in which as shown in FIG. 4 and FIG. 7, the discharging portion 35 of the developer bag 16 is placed in a state in which the sealing member 19 is folded back with respect to an unsealing advancing direction (arrow E direction in the figures). For example, in the state of FIG. 4, the unsealing member 20 is rotated (an arrow C direction in the figure), so that the scaling member 19 is pulled in a pulling direction (arrow D direction in the figure) by the unsealing member 20. By doing so, the developer bag 16 and the sealing member 19 provide an inclined peeling positional relationship, as shown in FIG. 12, in which the narrow angle Q between the surface of the bonding portion 22 of the developer bag 16 and the surface along the pulling direction (arrow D direction) of the scaling member 19 is 90 degrees or less. It has been conventionally known that the peeling force necessary to pull off the both surfaces can be reduced by effecting the inclined peeling. Accordingly, as described above, the sealing member 19 is placed in the folded-back state with respect to the unsealing advancing direction (arrow E direction in the figure), so that the sealing member 19 at the bonding portion 22 and the developer bag 16 are placed in the inclined peeling positional relationship, and the peeling force can be adjusted so as to be reduced.

<Structure of Unsealing Member>

[0133] The unsealing member 20 is used for the purpose of peeling the sealing member 19 from the developer bag 16 by applying a force to the sealing member 19 to move the sealing member 19. The unsealing member 20 includes a supporting portion (not shown) which has a shaft shape and which is rotatably supported by the second frame 18 at its ends, and includes an engaging portion 20b for fixing the portion-to-be-engaged 19b of the sealing member 19. In this embodiment, the unseal member 20 has a rectangular shaft shape, and the portion-to-be-engaged 19b of the sealing member 19 is engaged with the engaging portion 20b at one surface of the rectangular shaft.

(Combined Use as Unsealing Member, Urging Member and Stirring Member)

[0134] Further, the urging member 21 for externally acting on the developer bag 16 to discharge the developer accommodated in the developer bag 16, and the unsealing member 20 may be separate members, respectively, but in this embodiment, the same part performs functions of the unsealing member 20 and the urging member 21.

[0135] Further, a function of stirring the developer discharged from the developer bag 16 and a function of the unsealing member 20 may be performed by separate members, respectively, but in this embodiment, the unsealing member 20 also perform the stirring function as the same part.

(Effect of Combined Use as Unsealing Member, Urging Member and Stirring Member)

[0136] Thus, by using the same part (member) as the unsealing member 20, the urging member 21 and the stirring member, the number of parts is reduced, so that it becomes possible to realize cost reduction and space saving.

<Summary of Unsealing of Developer Bag>

[0137] The unsealing of the developer bag 16 will be described with reference to FIG. 7 and FIG. 8.

[0138] The developing device 38 includes a power application point portion 20a where the unsealing member 20 applies the force for pulling the sealing member 19 in order to effect the unsealing, and includes the fixing portion 18a of the frame for fixing the developer bag 16 to be pulled.

[0139] The power application point portion 20a is a portion, closest to the bonding portion 22, of a portion where the sealing member 19 and the unsealing member 20 contact at the moment of the unsealing. In (b) of FIG. 7, a corner portion 20c of the unsealing member is the power application point portion 20a. The fixing portion 18a of the second frame 18 includes a fixing portion 18c for suppressing movement of the developer bag 16 caused by the force during the unsealing. Further, from the bonding portion 22, in this embodiment, the first fixing portion 18a of the frame and the first bonding portion 16d of the developer bag are bonded by the ultrasonic clamping, and as shown in (b) and (c) of FIG. 7 and (a) of FIG. 8, a portion, near the bonding portion 22, of the ultrasonic clamping portion of the first fixing portion 18a constitutes the fixing portion 18c.

[0140] First, as shown in FIG. 4, the unsealing member 20 is rotated in the arrow C direction by transmission of the driving force thereto from the main assembly by an unshown during means.

[0141] Then, a state immediately before the sealing member 19 is pulled by further rotation of the unsealing member 20 to start the unsealing of the first bonding portion 22a is shown in FIG. 5 and (b) of FIG. 7. With the rotation, the sealing member 19 fixed to the unsealing member 20 by the portion-to-be-engaged 19b is pulled in the arrow D direction by the corner portion 20c (power application point portion 20a) of the rectangular unsealing member 20.

[0142] When the sealing member 19 is pulled, the developer bag 16 is pulled via the bonding portion 22. Then, a force is applied to the first fixing portion 16d of the developer bag 16, so that the developer bag 16 is pulled from the fixing portion 18c toward the power application point portion 20b by the fixing portion 16c. Then, in a cross section perpendicular to the rotation shaft of the unsealing member 20, the first bonding portion 22a is moved so as to approach a line connecting the power application point portion 20a and the fixing portion 18c. At this time, with respect to the arrow D direction, from a side close to the rotation shaft of the unsealing member 20, the portions are disposed in the order of the openings 35a, the first bonding portion 22a, the fold-back portion 19d and the fixing portion 18c ((b) of FIG. 7). Further, the unsealing member 19 is folded back between the first bonding portion 22a and the portion-to-be-engaged 19b and therefore the force is applied to the portion of the first bonding portion 22a so as to be inclination peeled in the arrow D direction. Then, the peeling of the first bonding portion 22a is effected to start the unsealing of the discharging portion 35.

[0143] Further, together with the corner portion 20c, also the power application point portion 20a is moved in the arrow C direction, and when the sealing member 19 contacts a corner portion 20d, the power application point portion 20a is moved from the corner portion 20c to the corner portion 20d. Here, (b) of FIG. 7 shows a state in which the power application point portion 20a is the corner portion 20c, and (c) of FIG. 7 shows a state in which the unsealing member 20 in further rotated and the power application point portion is moved to the corner portion 20d.

[0144] As shown in FIG. 6 and (c) of FIG. 7, together with advance of the unsealing with further rotation of the unsealing member 20, also the fold-back portion 19d advanced in the arrow E direction. Then, the unsealing further advances, so that the openings 35a are exposed. A state in which the peeling of the second bonding portion 22b is to be started after the openings 35a are exposed is shown in (a) of FIG. 8. Also at this time, similarly as the peeling of the first bonding portion 22a, the sealing member 19 is pulled toward the power application point portion 20a, and the developer bag 16 stands firm toward a direction of the fixing portion 18c (arrow H direction). Then, in a cross section perpendicular to the rotation shaft of the unsealing member 20, the second bonding portion 20b is moved so as to approach a line connecting the power application point portion 20a and the fixing portion 18c. Then, the force is applied to the portion of the bonding portion 22b in the arrow D direction, so that the second bonding portion 22b is peeled. Then, the second bonding portion 22b is peeled to complete the unsealing ((b) of FIG. 8 and FIG. 9). Then, the developer inside the developer bag 16 passes through the openings 35a of the discharging portion 35, and is disposed in an arrow I direction.

[0145] Thus, the sealing member 19 is wound up around the unsealing member 20 by the rotation of the unsealing member 20, so that the bonding portion 22 is unsealed. The sealing member 19 is wound up by the rotation and therefore a space required to move the unsealing member 20 may only be required to be a rotation space, and compared with the case where the sealing member 19 is moved by movement other than the rotation, it is possible to realize space saving.

[0146] By providing the sealing member 19 with the told-back portion 19d, the bonding portion 22 can be inclination-peeled without effecting shearing peeling and can be unsealed with reliability.

[0147] Further, the portion-to-be-engaged (19b), to be engaged with the unsealing member 20, for unsealing the sealing member 19 in an end side of the sealing member 19 with respect to a direction substantially perpendicular to the direction (arrow F direction in FIG. 3) in which the plurality of openings 35a are arranged is provided, so that the sealing member 19 can be engaged and unsealed with reliability.

[0148] Further, by providing the frame with the fixing portion 18c, the developer bag 16 is supported during the unsealing, so that even a soft and deformable developer bag 16 becomes unsealable with reliability.

[0149] Further, with respect to the discharge of the developer during the unsealing, as described above, the bonding portion 22 is moved on the line connecting the power application point portion 20a and the fixing portion 18c tin the order of (a) of FIG. 7, (b) of FIG. 7, (c) of FIG. 7 and (a) of FIG. 8). By this motion, the developer ac the periphery of the openings 35a is moved, so that agglomeration of the developer can be broken.

(Arrangement Relation of Fixing Portion Associated with Unsealing)

[0150] As shown in FIG. 4, in order to peel off the first bonding portion 22b with reliability, the following arrangement relation is required between the first bonding portion 22b and the fixing portion 18c (fixing portion 16d). During the unsealing, with respect to the fixing portion 18c, the unsealing member 20 pulls the sealing member 19 in the arrow D direction. At this time, with respect to the movement direction (arrow D direction) of the sealing member 19 by the unsealing member 20, the fixing portion 18c is provided in an upstream side of the openings 35a. For that reason, as shown in FIG. 5, a force is applied to the fixing portion 18c in the arrow H direction. Therefore, when the unsealing force is applied, the sealing member 19 is pulled in the arrow H direction and the arrow D direction between the fixing portion 18c and the unsealing member 20 to apply a force to the first bonding portion 20a, thus advancing the unsealing in the arrow E direction. Thus, it the fixing portion 18c is not provided upstream with respect to the movement direction (arrow D direction) of the sealing member 19, the entire developer bag 16 is pulled in the direction in which the unsealing member 20 is pulled, so that the force cannot be applied to the first bonding portion 22a and the unsealing cannot be effected.

[0151] In this way, the fixing portion 18c (fixing portion 16d) is provided upstream with respect to the movement direction (arrow D direction) of the scaling member 19, so that reliable unsealing becomes possible.

[0152] As described above, the developer bag 16 may preferably have flexibility, and the fixing portion 16d is required that the fixing portion 16d is not deformed and broken by the unsealing force. In the case where the multi-layer structure portion 16g is subjected to the unsealing force in the constitution including the interlayer bonding portion 16h, the multi-layer structure portion 16g can be integrally subjected to reaction force to the unsealing force. By this, it is possible to compatibly realize the flexibility of the developer bag 16 and prevention of the fixing portion 16d from being deformed and broken.

(Distance Relation of Fixing Portion Associated with Unsealing)

[0153] As shown in FIG. 22 and FIG. 23, in order to peel off the first bonding portion 22b with reliability, the following length relationship is required between the first bonding portion 22a and the fixing portion 18c. First, a point of the first bonding portion 22a finally peeled off when a flat surface which passes the unsealing member 20, the openings 35a and the fixing portion 18c and which is perpendicular to the rotation shaft of the unsealing member 20 is viewed, is a first point 22d. The first point 22d is an end portion point of the first bonding portion 22a close to the openings 35a. Further, a distance from the fixing portion 18c to the first point 22d along the developer bag 16 is M1. Further, a distance measured, from the first fixing portion 18d to the first point 22d, along the developer bag 16 with respect to the direction including the openings 35a is M2. Incidentally, the openings 35a are a space in which the material for the developer bag 16 is not present but a width of the openings 35a is also included in the distance.

[0154] At this time, M1<M2 is satisfied to permit the peeling-oft of the first bonding portion 22a. Here, the above relationship of M1<M2 will be described specifically.

(Case of M1<M2)

[0155] First, in the case where M1<M2 is satisfied, as shown in FIG. 22, a force (arrow D direction) for pulling the sealing member 19 to the first bonding portion 22a by the unsealing member 20 and a retaining force (arrow H direction) of the fixing portion are applied to the first bonding portion 22a, so that the first bonding portion 22a can be inclination-peeled. By effecting the inclination peeling, the peeling force can be set at a low level. Here, (a) of FIG. 22 shows before the unsealing, and (b) of FIG. 22 shows immediately before the first bonding portion 22a is unsealed.

(Case of M1>M2)

[0156] On the other hand, in the cane of M1>M2, as shown in FIG. 23, the pulling force by the unsealing member 20 is not applied to the first bonding portion 22a but in applied to the second bonding portion 22b. In this case, the force is not applied to the first bonding portion 22a and therefore the first bonding portion 22a is not peeled. In this case, the force (arrow D direction) from the unsealing member 20 and the retaining force (arrow H direction) of the fixing portion 18c are applied to the second bonding portion 22b. In this state, to the second bonding portion 22b, the force (arrow D direction) for pulling the sealing member 19 by the unsealing member 20 and the retaining force (arrow H direction) of the fixing portion 18c (in the arrow H direction) are applied. At the portion of the second bonding portion 22b, the peeling relationship is a shearing peeling relationship and therefore it is difficult to unseal the second bonding portion 22b. This is because the shearing peeling requires a large force compared with the inclination peeling.

[0157] Here, (a) of FIG. 23 is a view before the unsealing, and (b) of FIG. 23 is a view when the force (arrow D direction) for pulling the sealing member 19 by the unsealing member 20 is applied to the bonding portion (the second bonding portion in this case) by the rotation of the unsealing member 20. Further, to the second bonding portion 220, the force is applied but is applied based on the shearing peeling relation, and therefore compared with the case of the inclination peeling, a very large force is required, so that it becomes difficult to reduce the peeling force.

(Case of Plurality of Fixing Portions)

[0158] Here, a relation between a plurality of fixing portions and the unsealing will be described by using FIG. 30. Immediately, before the unsealing member 20 is rotated from a state of (a) of FIG. 30 to unseal the first bonding portion 22a is (b) of FIG. 30. In this embodiment, the first fixing portion 18a and the second fixing portion 18b are provided. Here, the force during the unsealing is applied to the first fixing portion 18a disposed at a place close to the first bonding portion 22a which is first unsealed while sandwiching the openings 35a between the portions 22a and 22b. For that reason, the second fixing portion 18b is not required to be taken into consideration of the measuring manners of the distances M1 and M2 (see FIG. 22 and FIG. 23) described above. Thus, in the case where there are the plurality of fixing portions, the fixing portion disposed at the place close to the first bonding portion 22a which is first unsealed while sandwiching the openings 35a, between the portions 22a and 22b, to which the force during the unsealing is to be applied may be used as a basis (of the unsealing).

(Positional Relation of Second Bonding Portion)

[0159] An arrangement in which the second bonding portion 22b can be more satisfactorily unsealed without being wound up around the unsealing member 20 will be described by using FIG. 12 shows a state immediately before the first bonding portion 22a is unsealed. First, an end portion of the first bonding portion 22a in a side remote from the openings 35a is a second point 22e. An end portion of the second bonding portion 22b in a side remote from the openings 35a is a third point 22f. Here, a distance from the second point 22e to the third point 22f is L1. Further, a distance from the second point 22e to the power application point portion 20a is L2. At this time, a relationship between the distance L1 and the perpendicular to L2 needs a relationship of L1<L2.

[0160] The reason thereof is that in the case where L1 is distance L2, the second bonding portion 22b reaches the power application point portion 22a before the peeling of the second bonding portion 22b is ended, and the second bonding portion 22b is wound about the unsealing member 20. The force cannot be applied so as to peel off the sealing member 19 from the second bonding portion 22b. For that reason, it becomes difficult to unseal the sealing member 19 from the developer bag 16.

[0161] As described above, the relationship between the distance L1 and the distance L2 is made L1<L2, the sealing member 19 is satisfactorily unsealable without being wound about the unsealing member 20.

(Function of Connecting Portions Defining Openings)

[0162] A summary of the connecting portions 35b, defining the openings, which perform a large function in the unsealing operation of the developer bag 16 will be described.

[0163] FIG. 11 is a view of the discharging portion 35 when the peeling of the portion, at the first bonding portion 22a, to be first unsealed is ended to expose the openings 35a, and is a state in which the peeling at the second bonding portion 22b is not ended. As described above, the discharging portion 35 includes the plurality of openings 35a disposed at different positions with respect to the perpendicular direction (arrow F direction) to the unsealing direction (arrow E direction) in which the exposure of the openings 35a advances. For that reason, also the plurality of connecting portions 35b defining the plurality of openings 35a are disposed at a plurality of positions with respect to the F direction. By this, the plurality of connecting portions 35b bridge the first bonding portion 22a and the second bonding portion 22b with respect to the direction (arrow E direction) in which the unsealing of the openings 35a advances. For that reason, at the time of the state of FIG. 8 in which the unsealing of the first bonding portion 22a is ended, the force when the second bonding portion 22b is unsealed can be received by the first fixing portion 16d via the connecting portions 35b, so that the force for peeling off the sealing member 19 from the developer bag 16 can be transferred. That is, the forces are applied to the second bonding portion 22b in the arrow D direction and the arrow E direction, so that also at the second bonding portion 22b, the sealing member 19 is peelable.

[0164] A similar effect can be obtained also in cases other than the case where the openings 35a are arranged in the direction (arrow F direction) perpendicular to the unsealing direction (arrow E direction) as shown in (b) of FIG. 27 as described above. Even when the openings 35a are not completely arranged in the direction perpendicular to the unsealing direction as shown in (c) of FIG. 28, the connecting portions 35b can transmit the force, for peeling off the sealing member 19 from the developer bag 16, as in an arrow P direction. Further, even when the openings 35 overlap with each other with respect to the unsealing direction as shown in (d) of FIG. 27, the connecting portions 35b can transmit the force, for obliquely peeling the sealing member 19 from the developer bag 16, as in the arrow P direction. That is, the plurality of openings 35a may only be required to be disposed at different positions with respect to the direction (arrow F direction) perpendicular to the unsealing direction (arrow E direction).

[0165] Further, as shown in (b) of FIG. 27, a portion including the connecting portions 35b at a periphery of the openings 35s may also be used as the bonding portion 22. Also in this case, by the presence of the connecting portions 35b, the force can be transmitted to the end of the peeling at the bonding portion 22, so that the unsealing is effected with reliability.

[0166] Further, as for a relationship between the rotation shaft of the unsealing member 20 and the openings 35a, it can be the that the openings 35a are disposed at the different positions with respect to the direction (arrow F direction) of the rotation shaft of the unsealing member 20. By doing so, the connecting portions 35b for bridging the first and second bonding portions 22a and 22b with respect to the perpendicular direction (arrow E direction) to the rotation shaft of the unsealing member 20. The openings 35a may only be required to be located at the different positions in the rotational axis direction (arrow F direction) of the unsealing member. Even when the openings 35a overlap with each other with respect to the rotational axis direction (arrow F direction) as shown in (b) of FIG. 27 and do not overlap with each other completely with respect to the rotational axis direction (arrow F direction) as shown in (c) of FIG. 27, the force can be transmitted as in the arrow P direction and there is the effect of the connecting portions 35b.

[0167] Thus, by the presence of the connecting portions 35b for bridging the first and second bonding portions 22a and 22b at the discharging portion 35, the developer accommodating container 26 accommodating the developer and the developer accommodating container 30 including the unsealing member 20 can transmit the unsealing force of the unseal member 20 until the second bonding portion 22b is unsealed, so that the unsealing can be effected with reliability.

[0168] Further, a relationship between the openings 35a and the portion-to-be-engaged 19b of the sealing member will be described (FIG. 3). The portion-to-be-engaged 19b is provided in an end side of the sealing member 19 with respect to the direction substantially perpendicular to the direction in which the plurality of openings are arranged.

[0169] A relationship between the openings 35a and the unsealing member 20 will be described (FIG. 3). The unsealing member 20 is provided in an end side of the sealing member 19 with respect to the direction substantially perpendicular to the direction in which the plurality of openings are arranged.

[0170] Also in such a constitution, it is possible to obtain the effect of transmitting the unsealing force of the unsealing member 20 by the connecting portions 35b until the second bonding portion 22b is unsealed.

(Example in which Connecting Portions are Separate Members)

[0171] Further, the connecting portions 35b defining the openings 35a may also be a separate member (connecting members 16f) as shown in FIG. 21. In this case, a constitution in which a single long opening 16a in the direction (arrow F direction) perpendicular to the unsealing direction (arrow E direction) is provided and the connecting members 16f as the separate member connecting both sides of the opening 16a along the unsealing direction (arrow E direction) are provided on the single long opening 16a is employed. At this time, the connecting members 16f are bonded in each of the first bonding portion 22a side and the second bonding portion 22b side of the long single opening 16a by adhesive bonding, welding or the like.

[0172] Incidentally, also in the case where the developer bag 16 is provided with the connecting members 16f, the sealing member 19 is folded back between the bonding portion 22 and the portion-to-be-engaged 19b as described above and is wound around the unsealing member 20, so that the developer bag 16 is unsealable. By employing much a constitution, the connecting portions 35b defining the openings in the case where the plurality of openings 35a are provided, and the connecting members 16f perform the same function. That is, the long single opening 16a is the same as the case where there are the plurality of openings 35a by providing the connecting members 16f.

[0173] Therefore, when the sealing member 19 is peeled at the second bonding portion 22b after the unsealing at the first bonding portion 22a is ended, the force (arrow D direction) during the unsealing at the second bonding portion 22b by the unsealing member 20 can be received by the first fixing portion 16d via the connecting members 16f with respect to the arrow H direction. Therefore, the force for peeling the sealing member 19 from the developer bag 16 can be transmitted. That is, the forces are applied to the second bonding portion 22b in the arrow D direction and the arrow H direction, so that the unsealing is so enabled also the second bonding portion 22b.

[0174] In this way, the long single opening 16a forms the plurality of openings 35a by the connecting members 16f, so that it also becomes possible to strengthen only the connecting members 16f.

(Problem of Unsealing Property in Case of No Connecting Portion)

[0175] Here, an example in which the present invention is not applied and it is difficult to unseal the developer bag 16 will be described. This is, as shown in FIG. 13, FIG. 14 and FIG. 15, the case where there are no connecting portions 35b and it becomes difficult to effect the unsealing. FIG. 13 is an example in which there are no connecting portions 35b and there is a single opening 16a, in which (a) of FIG. 13 is a view showing a state before the peeling at the second bonding portion 22b, and (b) of FIG. 13 and FIG. 15 are views showing a state when the sealing member 19 is peeled at the second bonding portion. Further, FIG. 8 includes enlarged sectional views at a periphery of the opening 35a in states before and after the sealing member 19 is peeled at the second bonding portion 22b in this embodiment, and FIG. 14 includes sectional views at the periphery of the opening 35a in the case where there are no connecting portions 35b and thus it becomes difficult to effect the unsealing.

[0176] In this case, a state in which the unsealing advances to the second bonding portion 22b is (a) of FIG. 14, and from this state, the sealing member 19 is pulled and moved in the arrow D direction by further rotation of the unsealing member 20. Then, since there are no connecting portions 35b, the force from the first fixing portion 16d cannot be transmitted to the second bonding portion 22b side at the central portion of the opening 16a. For that reason, as shown in (b) of FIG. 14 and (b) of FIG. 13, a binding force from the fixing portion 18a of the frame to the second bonding portion 22b is eliminated, so that the opening 16a gradually opens largely in the arrow D direction. Further, the second bonding portion 22b is pulled by the sealing member 19, so that the opening 16a is deformed as shown in (c) of FIG. 14. In this case, a force acting on the second bonding portion 22b fails to provide the inclination peeling positional relationship as shown in FIG. 8 and causes the shearing peeling (approximately 0-degree peeling) by the deformation of the opening 35a as shown in (c) of FIG. 14, so that a large force is required for the peeling. Moreover, the supporting force of the first fixing force 16d cannot be transmitted to the second bonding portion 22b and therefore the second bonding portion 22b is pulled by the unsealing member 20 without causing the peeling of the sealing member 19 therefrom. For that reason, the opening 16a in the neighborhood of a longitudinal central portion of the second bonding portion 22b further opens largely, so that the second bonding portion 22b is wound about the unsealing member 20.

[0177] Incidentally, if a member for accommodating the developer is a rigid member such as a structure, there is no such a deformation, so that the sealing can be made as in the conventional example. However, in the case of a constitution in which the developer is accommodated in a deformable soft bag-like member and an opening which is deformed during unsealing is unsealed, as described above, when there are no connecting portions 35b, it becomes difficult to effect the unsealing.

[0178] As described above, the sealing member 19 (=toner seal) is made unsealable by transmitting the driving force to the unsealing member 20 of the image forming apparatus B main assembly, and there is no need for the user to peel off the toner seal, so that the developing device 38 and the process cartridge A can be more simply replaced and used. Further, the sealing member 19 after the unsealing is fixed to the unsealing member 20 so that the unsealing can be effected without removing a waste material from the process cartridge A.

<With Respect to Summary of Urging Member and Developer Discharge>

[0179] Next, the developer discharge by the urging member will be described by using the drawings.

(Urging Member)

[0180] As shown in FIG. 16, the urging member 21 is provided with a shaft portion 21a and an urging sheet 21b fixed to the shaft portion 21a and is provided rotatably inside the first frame 17 and the second frame 18.

[0181] First, the shaft portion 21a performs a function by the same part as the unsealing member 20 (21a=20). Therefore, as described above, the driving force is transmitted to the shaft portion 21a by the unshown driving means of the image forming apparatus main assembly B, so that the urging member 21 (=20) is rotated in the arrow C direction.

[0182] Next, the urging sheet 21b is fixed on a surface of a rectangular shat portion 21a in cross section and is rotated together with the shaft portion 21a. Incidentally, the urging sheet 21b is a flexible sheet formed of a material such as PET, PPS (polyphenylene sulfide) or polycarbonate, in a thickness of about 0.05-0.1 mm, and an end thereof projects to the outside of a circumscribed circle of the shaft portion 21a. Here, in this embodiment, on different surfaces of the shaft portion 21a, the sealing member 19 and the urging sheet 21a are fixed but may also be fixed on the same surface of the shaft portion 21a.

[0183] Further, as shown in FIG. 16 and FIG. 17, the urging sheet 21b also performs the function of stirring the developer and feeding the developer toward the developing roller 13 and the developer supplying roller 23.

<Summary of Developer Discharge from Developer Bag>

[0184] Next, the developer discharge from the developer bag will be described by using the drawings.

(Summary of Discharge from Before Unsealing to During Unseal)

[0185] First, with respect to the discharge of the developer from before the unsealing to the time of start of the unsealing, as shown in FIG. 7 and FIG. 8 described above, the sealing member 19 is pulled toward the power application point portion 20a (arrow D direction), and the developer bag 16 is supported by the fixing portion 18c. For that reason, during unsealing, three places consisting of the power application point portion 20a, the fixing portion 18c of the frame and the place of the bonding portion 22 where the sealing member 19 is peeled are moved in a direction in which these three places are aligned in a rectilinear line in a cross section perpendicular to the rotation shaft of the unsealing member 20. Thus, the position of the openings 35a is changed between the time before the unsealing member 20 applies the force to the sealing member 19 to perform the unsealing operation and the time when the unsealing operation is started to unseal the bonding at the first bonding portion 22a, so that stagnation of the developer in the neighborhood of the openings 35a can be prevented and a discharging property is good.

(Summary of Discharge after Unsealing/During Urging)

[0186] Further, after the unsealing, when the sealing member 19 is unsealed from the above-described developer bag 16 as shown in (b) of FIG. 8, the openings 35a are disposed to open toward below the developer bag 16 and therefore the developer in the neighborhood of the openings 35a is discharged by the action of gravitation and vibration or the like of the developer bag 16 during the unsealing.

[0187] After the unsealing, when the unsealing member 20 is further rotated, also the urging sheet 21b fixed to the unsealing member 20, for urging the developer bag 16 is rotated, so that the urging sheet 21b is wound about the unsealing member 20 by the developer bag 16 as shown in FIG. 9. Here, as shown in FIG. 16, the urging sheet 21b has elasticity and therefore is likely to be restored to an original shape, thus urging the developer bag 16 in an arrow J direction. At this time, the developer bag 16 is urged by the urging sheet 21b and is pressed against the second frame 18 via the toner, so that the entire developer bag 16 is deformed. Further, the developer bag 16 is urged by the urging sheet 21b to be decreased in its inside volume. Thus, by the decrease in volume of and the change in entire shape of the developer bag 16, the developer inside the developer bag 16 is stirred, and thereby, the developer is readily discharged from the openings 35a. Further, at this time, the developer bag 16 is closed except for the openings 35a and there is no escape route except for the openings 35a, and therefore the discharging property from the openings 35a is high. By the discharging action as described above, the developer is readily discharged in the arrow I direction.

[0188] Incidentally, at this time, if the developer bag 16 is contacted to and pressed against the second frame 18 at least at a part thereof, the developer bag 16 is deformable.

[0189] Further, by aligning the rotational axis direction of the developing roller 13 and the arrangement direction (arrow F direction) of the plurality of openings 35a, the developer can be easily supplied over the entire longitudinal direction of the developing roller 33 during the discharge without being localized.

[0190] Further, when the developing device 38 is mounted in the image forming apparatus main assembly B, by providing the openings 35a so as to open toward the direction of gravitation, the developer discharging property can be improved.

[0191] Further, the urging member 21 provided inside the frames (17, 18) urges the developer bag 16 so as to be pressed against the second frame 18, by which the developer discharging property can be improved.

(Summary of Discharge/Developer Bag Shape Restoration)

[0192] Then, as shown in FIG. 17, the unsealing member 20 is further rotated, so that the urging sheet 21b is separated from the developer bag 16. At this time, the developer bag 16 has flexibility and therefore is likely to be restored to the state before the urging by the weight of the developer (arrow K direction). Then, also the urging sheet 21b is rotated and urges the developer bag 16 toward the second frame 18 as shown in FIG. 16, so that the developer bag 16 is deformed to move the developer at a position other than the neighborhood of the openings 35a, and the developer is discharged from the openings 35a.

(Summary of Discharge/Repetition of Unsealing and Restoration)

[0193] In the case where the developer immediately after the unsealing is present in the developer bag 16 in a large amount, an entering amount of the urging sheet 21b to the unsealing member 20 is repetitively changed, so that the developer bag 16 is deformed so as to be pressed against the second frame 18. Contraction of the developer bag 16 by the urging with the urging member 21 and restoration of the developer bag 16 by the weight of the developer inside the developer bag 16 and by the flexibility of the developer bag 16 are repeated. Further, by the above-described action, the developer bag 16 itself is moved and therefore the developer bag 16 is vibrated, so that the developer inside the developer bag 316 is discharged from the openings 35a also by this vibration. Further, the urging member 21 is rotated and therefore is capable of repetitively urging the developer bag 16.

(Example in which Developer Bag is Applied to Frame)

[0194] Incidentally, a portion 27 where the developer bay 16 is urged against the second frame 18 is as shown in FIG. 24, even in the case where a bonding portion 28 such as an adhesive or a double-side tape is provided and bonds the developer bag 16 to the second frame 18, the urging sheet 21b can urge the developer bag 16 to discharge the developer.

(Case where Amount of Developer Becomes Small)

[0195] Incidentally, the case where the amount of the developer inside the developer bag 16 becomes small by effecting image formation will be described by using FIG. 31. Immediately after the unsealing, as shown in (a) of FIG. 31, the shape of the developer bag 16 follows the shape of the urging member 21 so that the developer bag 16 always contacts the urging member 21 by the weight of the accommodated developer, and a size (inside volume) is periodically changed. However, when the accommodated developer becomes small, as shown in (b) of FIG. 31, the weight of the developer becomes light, so that the developer bag 16 does not follow the urging member 21 and repeats periodical separation from and contact with the urging member 21. For that reason, a size (inner volume) of the developer bag 16 is not so changed. For that reason, a discharging effect by the change in inner volume of the developer bag 16 becomes small, but the developer bag 16 and the urging member 21 periodically contact each other to vibrate the developer bag 16, so that the developer can be discharge.

(Combined Use as Urging Sheet and Sealing Member)

[0196] Incidentally, a single part may also be used as the urging sheet 21b and the sealing member 19 to have functions of these members. That is, after the unsealing, the bonding portion 22 is separated from the developer bag 16 and therefore an end of the sealing member 19 in the bonding portion 22 side is a free end. For this reason, the sealing member 19 can have the function of the urging sheet 21b. Thus, the unsealing member 20 can have the function of the shaft portion 21a of the urging member 21, and the sealing member 19 can have the function of the urging sheet 21b.

[0197] By doing so, it is possible to reduce the number of parts and thus cost reduction can be realized.

[0198] As described above, the developer inside the developer bag 16 can be satisfactorily discharged without providing another discharging part such as a developer discharging roller at the openings 35a as a developer discharging port, so that agglomeration and bridge of the developer in the neighborhood of the openings 35a can be prevented. By this, even in the case where the developer in the developer bag 16 is agglomerated by tapping during transportation, storage or the like, the agglomerated developer is broken by such movement of the entire developer bag 16 and the periphery of the openings 35a, so that it is possible to prevent a state in which it becomes difficult to discharge the developer.

(Example in which Urging Member is Single Part)

[0199] Further, the urging member 21 is not separate parts consisting of the shaft portion 21a and the urging sheet 21b, but even when the urging member 21 is a single part as shown in (a) of FIG. 25 and is provided with a projection (projected portion) 21e functioning as the urging sheet 21b, the developer can be similarly discharged. In the case where the urging member 21 is constituted by only the shaft portion 21a, when the urging member 21 is viewed in its cross section perpendicular to its rotation center, the developer bag 16 can be pressed against a frame 29 to be deformed even in the case where the cross section of the shaft portion 21a has a polygonal shape ((b) of FIG. 25) or has a cam shape ((c) of FIG. 25). This is because when the urging member 21 is disposed so as to contact at least the developer bag 16, a distance from the rotation center to the outer end of the urging member 21 is changed and therefore the entering amount of the urging member 21 to the developer bag 16 is also changed. That is, so long as the shaft portion is not a shaft having a circular cross section including the rotational axis as its center, the developer bag 16 can be deformed by the rotation of the urging member 21. As shown in (a) of FIG. 25, a distance 21c from the center of the urging member 21 to a remote outer end of the urging member 21 and a close distance 21d to an outer end are different from each other and therefore the entering amount of the urging member 21 to the developer bag 16 is also changed.

[0200] Further, (b) of FIG. 32 is a sectional view of an urging member 21 having a cross-shape in cross section, and (a) of FIG. 32 is a cross-sectional illustration of the developer accommodating unit 25 including the cross-shaped urging member 21. As shown in FIG. 32, in the case where four projections (projected portions) 21e having the same distance from the center of the urging member 21 to the outer end are provided, outer configurations (distances 21c) of the four projections 21e are equal to each other. However, the urging member 21 includes a portion, other than the projections 21e, having an outer end (distance 21d) close to the center and therefore the entering amount to the developer bag 16 can be changed. That is, the urging member 21 can be made a rotatable member including portions different in distance from the rotation center of the urging member 21 to the outer end of the urging member in the cross section perpendicular to the rotation center of the urging member 21.

[0201] Thus, the developer bag 16 is urged by the urging member 21 (arrow J direction) to be pressed against the frame 29, thus being deformed to decrease its inside volume, so that the inside developer is pushed out to be discharged from the openings 35a (arrow I direction).

[0202] Further, in an attitude during the image formation, the shaft portion 21a (=20) of the urging member 21 is positioned under the developer bag 16 with respect to the direction of gravitation, and contacts the developer bag 16. Further, the cross-sectional shape of the shaft portion 21a (=20) of the urging member 21 is rectangular and is not circular, and therefore by the rotation of the shaft portion 21a (=20), the entering amount of the shaft portion 21a (=20) to the developer bag 16 is periodically changed as described above. Also by the change in entering amount of the shaft portion 21a (=20) to the developer bag 16, the developer bag 16 can be changed in volume and can be vibrated, so that the developer discharging property can be improved.

[0203] Further, as described above, the developer bag 16 includes the multi-layer structure portion 16g where the sheet 36u (or the sheet 16s) for forming the developer accommodating portion is superposed. Further, at this multi-layer structure portion 16g, the first fixing portion 16d to be fixed to the fixing portion of the frame is provided. Further, the interlayer bonding portion 16h for bonding between the superposed sheet 16u (or the sheet 16s) is provided between the first fixing portion 16d of the multi-layer structure portion 16g and the developer accommodating portion.

[0204] By this, in the developer accommodating unit 25 using the developer bag 16 for accommodating the developer, the unsealing characteristic of the sealing member 19 for sealing the openings 35a of the developer bag 16 can be improved.

[0205] Elements having constitution and functions (actions) which are identical or correspond to those in First Embodiment are represented by the same symbols and will be omitted from detailed description.

[0206] As described above, in First Embodiment, the multi-layer structure portion 16g where the sheet 36u or the sheet 16s is superposed by being folded back is constituted, but the multi-layer structure portion is not limited thereto.

[0207] In this embodiment, as shown in (a) of FIG. 35, the outside of the bonding together portion 16i of each of the sheet 16u and the sheet 16s is extended, so that a portion where the sheet 16u and the sheet 16s constitute the two layers is the multi-layer structure portion 16g. Further, a constitution in which at this multi-layer structure portion 169, the first fixing portion 16d as the fixed portion is disposed is employed.

[0208] As in First Embodiment, in the case where the multi layer structure portion 16g where the sheet is superposed by being folded back is provided, when the bonding-together portion 16i is intended to also function as the interlayer bonding portion 16h, there is a need to bond together sheets of three layers or more at the same time, so that it is difficult to effect stable bonding. The bonding-together portion 16i is a portion constituting the developer accommodating portion of the developer bag 16 and is required to permit bonding which does not cause leakage of the developer. As a result, in the case of the multi-layer structure portion 16i in First Embodiment, there is a need to separately provide the bonding-together portion 16i and the interlayer bonding portion 16h.

[0209] On the other hand, in this embodiment, the multi-layer structure portion 16g of the two layers which are superposed without folding back the sheets can be constituted, and moreover the interlayer bonding portion 16h and the bonding-together portion 16i have the same sheet constitution, and therefore the bonding-together portion 16i can also perform the function of the interlayer bonding portion 16h.

[0210] Similarly, as shown in (b) of FIG. 33, in the case where the constitution of the developer bag 16 is the sheet 16s only, a constitution in which the outside of the bonding-together portion 16i of the sheet 16s is extended, and a portion where the sheet 16s constitutes the two layers is the multi-layer structure portion 16g, and the fixing portion 16d is disposed at this multi-layer structure portion 16g may also be employed.

[0211] It the constitution shown in (a) of FIG. 33 is employed, the multi-layer structure portion 16g is constituted by the sheet 16u and the sheet 16s which are two sheet materials different in mechanical characteristic. That is, elasticity and toughness characteristics are different between the sheet 16u and the sheet 16s. By this, compared with the constitution shown in First Embodiment and the constitution shown in (b) of FIG. 33, it is possible to provide the fixing portion 16d which is strong against a static force and which is also strong against impact.

[0212] As shown in FIG. 18, FIG. 19 and FIG. 34, in Third Embodiment, in place of the developer bags 16 in First and Second Embodiments, a developer accommodating member 34 is used.

(Vacuum Molding)

[0213] In the following, details of the developer accommodating member 34 will be described. The developer accommodating member 34 is formed by shaping a sheet-like material by vacuum molding, air-pressure molding or press molding, and is used. The developer accommodating container 30 including the unsealing member includes, similarly as in First Embodiment, the developer accommodating member 34, the sealing member 19, the unsealing member 20, the first frame 17 and the second frame 18. Incidentally, the unsealing member 20 is a member having the function of the urging member 21 and the developer stirring function similarly as in First Embodiment 1.

(Structure of Developer Bag)

[0214] As shown in FIG. 18 and (a) of FIG. 34, the developer accommodating member 34 is constituted by a molded portion 34a which is a flexible container formed by the vacuum molding, the air-pressure molding or the press molding, and (constituted by) a sheet-like air permeable portion 34b. Here, bonding between the molded portion 34a and the air permeable portion 34b is made by (heat) welding, laser welding, an adhesive, an adhesive tape or the like. The reason why an air permeability is imparted to the developer accommodating member 34 is the same as that in First Embodiment and is that the developer accommodating member 34 meets states during manufacturing, during transportation and during storage.

[0215] As the material for the molded portion 34a, ABS, PMMA, PC, PP, PE, HIPS, PET, PVC and the like and composite multi-layer materials of these materials are preferred. Further, the thickness of the molded portion 34a may preferably be about 0.1-1 mm in the sheet shape before the molding. The material and thickness of the molded portion 34a may only be required to be appropriately selected depending on cost, product specification, manufacturing condition, and the like.

[0216] As shown in (a) of FIG. 34, the molded portion 34a is bonded by the bonding-together portion 16i to the air permeable portion 34b at an outer peripheral portion 34c of the molded portion 34a. The developer accommodating member 34 accommodates the developer in an inner portion (the developer accommodating portion formed by the bonding). Further, outside the bonding-together portion 16i and at a portion where the outer peripheral portion 34c and the air permeable portion 34b overlap with each other, the fixing portion 16d (fixed portion) of the developer accommodating member 34 is provided. This fixing portion 16d is, similarly as in the above-described embodiments, the fixed portion fixed to the fixing portion of the frame. The shape of the molded portion 34a follows the inside (shape) of the frames 17 and 18 (FIG. 19).

[0217] Further, the developer accommodating container 26 in which the developer is accommodated is constituted by the developer accommodating member 34 and the sealing member 19 for unsealably covering the discharging portion 35 of the developer accommodating member 34 to seal the toner inside the developer accommodating member 34.

[0218] The developer accommodating container 30 including the unsealing member is constituted by the unsealing member 20 for unsealing the sealing member 19 from the developer accommodating member 34 and the developer accommodating container 26 in which the developer is accommodated.

[0219] The developing device 38 is constituted by the developer accommodating container 30 including the unsealing member, the developing roller 13 as the developing means, the developing blade 15, and the first frame 17 and the second frame 18 which support these members.

[0220] Here, the discharging portion 35 is provided at the molded portion 34a. Also a constitution of this discharging portion 35 is the same as that in First Embodiment, and a plurality of openings 35a and connecting portions 35b for defining the plurality of openings 35a are provided with respect to the direction (arrow F direction) substantially perpendicular to the unsealing direction (arrow E direction) in which the unsealing of the developer accommodating member 34 advances. That is, the plurality of openings 35a are disposed at different positions with respect to the direction (arrow F direction) perpendicular to the unsealing direction (arrow E direction). Further, the plurality of openings 35a are disposed at different positions with respect to the direction of the rotation shaft of the unsealing member 20. Further, the portion-to-be-engaged 19b is provided in an end side of the sealing member 19 with respect to the direction substantially perpendicular to the direction in which the plurality of openings 35a are arranged. Further, the unsealing member 20 is provided in the end side of the sealing member 19 with respect to the direction substantially perpendicular to the direction in which the plurality of openings 35a are arranged. The fixing portion includes a fixing portion 16d, necessary for the unsealing, corresponding to the first fixing portion 16d in First Embodiment. The shape of the developer accommodating member 34 itself is intended to be maintained by the molded portion 34a and the developer accommodating member 34 has the shape following the frame, and therefore the developer accommodating member 34 is supported by the frame as a whole, so that the developer accommodating member 34 is not readily moved toward the developer supplying roller 23 and the developing roller 13.

[0221] Next, as a means for fixing the fixing portion, it is possible to cite the (heat) welding, the ultrasonic welding, the adhesive bonding, the insertion between the frames, the heat clamping, the ultrasonic clamping, the hooking using the hole and the projection, and the like.

[0222] Incidentally, the constitutions of the sealing member 19 and the unsealing member 20 are the same as those in First Embodiment.

<Summary of Unsealing of Developer Bag>

[0223] Next, the unsealing of the developer bag will be described. Here, the fixing portion and the position thereof are the substantially same as those in First Embodiment, and also the force relationship is the same as that in First Embodiment. Therefore, also the unsealing step is the same as that in First Embodiment (FIG. 7 and FIG. 8).

[0224] In Third Embodiment, the openings 35a are disposed at the molded portion 34a, but also the molded portion 34a is flexible similarly as in First Embodiment, so that the force relationship is the same as that in First Embodiment. Therefore, also in Third Embodiment, the plurality of connecting portions 35b bridge the first bonding portion 22a and the second bonding portion 22b with respect to the direction (arrow E direction) in which the unsealing advances. For that reason, when the unsealing at the first bonding portion 22a is ended and the unsealing at the second bonding portion 22b is effected, a force for peeling the sealing member 19 from the developer accommodating member 34 can be transmitted. For that reason, the unsealing also at the bonding portion 22b becomes possible.

[0225] Also the developer discharging port after the unsealing is the same as that in First Embodiment. When the sealing member 19 is unsealed from the above-described developer accommodating member 34, first, the openings 35a are disposed at the lower portion of the developer accommodating member 34, and therefore the position of the openings 35a during the unsealing is moved at the same time when the gravitation acts on the openings 35a, so that the developer is discharged. Further, by the vibration or the like of the developer accommodating member 34, the developer in the neighborhood of the openings 35a is discharged. Here, the unsealing member 20 also functions as the urging member 21. Further, the urging member 21 has a rectangular shape in the cross section perpendicular to the rotational axis direction of the urging member 21, and the discharge of the developer is accelerated by the rotation of the urging member 21 as described in First Embodiment (FIG. 20).

[0226] Here, the urging member 21 contacts a surface which is the same surface 34f as the surface where the openings 35a of the developer accommodating member 34 are provided. Incidentally, the developer accommodating member 34 is constituted by a plurality of surfaces including the surface where the openings 35a of the developer accommodating member 31 are provided and another surface connected to the surface via a bent portion 34d.

[0227] By employing the constitution as described above, in addition to the effect in First Embodiment, the following effects are achieved.

(Effect of Vacuum Molding)

[0228] By forming a part of the developer accommodating member 34 through the vacuum molding, the following effects are obtained.

[0229] As a first effect, the developer accommodating member 34 can be shaped so as to follow the inside (shape) of the frame. For that reason, in the bag form as described in First Embodiment, it is difficult to insert the bag until corner portions of the frame, so that a gap (space) is formed between the developer accommodating member 34 and the first frame 17, and the space is not an effective developer accommodating space.

[0230] As a second effect, the developer accommodating member 34 can be shaped so as to follow (the shape of) the frame and therefore can be easily assembled with the frame. This is because there is no need to push the developer accommodating member into the frame during the assembling so that its shape follows the shape of the frame.

[0231] As a third effect, the developer accommodating member 34 is not readily moved toward the developer supplying roller 23 and the developing roller 13. This is because the developer accommodating member 34 is supported by the frame as a whole since the shape of the developer accommodating member 34 itself to maintained as described above by the vacuum molding and has the shape which follows (the shape of) the frame. For that reason, the second fixing portion for preventing the movement of the developer bag toward the developer supplying roller 23 and the developing roller 13 as described in First Embodiment can be omitted.

[0232] Further, as shown in FIG. 19, an effect of pushing the surface 34f which is the same surface as the surface where the openings 35a are provided is as follows. The developer accommodating member 34 is constituted by the plurality of surfaces by the vacuum molding. Therefore, the bent portion 34d is present between the plurality of surfaces. The surface of the developer accommodating member 34 is defined as a portion surrounded by bent portions. Here, a difference in effect between the case where the surface 34f including the openings 35a is urged and the case where a surface 34e which does not include the openings 35a is urged will be described. The surface 34e is a surface which sandwiches the bent portion 34d between itself and the surface 34f including the opening 35a. A force received by the surface 34e urged by the urging member 21 is transmitted via the bent portion 34d. The force is largely attenuated before it reaches the surface including the openings 35a. For that reason, also a force for moving the openings 35a becomes small compared with the case where the surface 34f including the openings 35a is urged directly. For that reason, the function (action) of discharging the developer by moving the openings 35a becomes small. Therefore, when the urging member 21 urges the surface 34f including the openings 35a, the urging member 21 can efficiently improve the discharging property of the inside developer and can prevent stagnation of the developer. Thus, by the rotation of the urging member 21 of which function is performed by the unsealing member 20, the developer accommodating member 34 is urged so as to be pressed against the second frame 18, so that the developer accommodating member 34 is deformed to change the position of the openings 35, and the inside develops is discharged. Further, there are the plurality of openings 35a and therefore the developer is readily discharged more than the case of a single opening. Further, the openings 35a are disposed downward with respect to the direction of gravitation in the attitude during the image formation and therefore the developer is easily discharged.

[0233] In this embodiment, as shown in (a) of FIG. 34, similarly as in Second Embodiment, the form of the multi layer structure portion 16g is described as an integral from between the interlayer bonding portion 16h and the bonding-together portion 16i but is not limited thereto. As shown in (b) and (c) of FIG. 34, similarly as in First Embodiment, a constitution in which as the sheet member, the multi-layer structure portion 16g where the outer peripheral portion 34c or the air permeable portion 34b is superposed by being folded back is provided and in which the interlayer bonding portion 16h is provided between the fixing portion 16d of this multi-layer structure portion 16g and the bonding-together portion 16i may also be employed. Further, similarly as in First Embodiment, the fold-back direction of the outer peripheral portion 34c or air permeable portion 34b which constitutes this multi-layer structure portion 16g may be which direction as shown in (b) and (c) of FIG. 34 (not shown).

[0234] However, if the constitution shown in (a) of FIG. 34 is employed, the multi-layer structure portion 16g is constituted by the outer peripheral portion 34c and the air permeable portion 34b which are two sheet materials different in mechanical characteristic. That is, elasticity and toughness characteristics are different between the molded portion 34a and the air permeable portion 34b. By this, compared with the constitutions shown in (b) and (c) of FIG. 34, it is possible to provide the fixing portion 16d which is strong against the static force and which is also strong against the impact.

[0235] Incidentally, in the above-described embodiments, as the process cartridge detachably mountable to the image forming apparatus main assembly, a process cartridge integrally including the photosensitive drum and, as process means acting on the photosensitive drum, the charging means, the developing means and the cleaning means was exemplified. However, the process cartridge is not limited thereto. For example, the process cartridge including, in addition to the photosensitive drum, either one of the charging means, the developing means and the cleaning means may also be used.

[0236] Further, in the above-described embodiments, the constitution in which the process cartridge including the photosensitive drum is detachably mountable to the image forming apparatus main assembly is exemplified but the present invention is not limited thereto. For example, an image forming apparatus in which the respective constituent elements are incorporated, or an image forming apparatus to which each of the constituent elements is detachably mounted may also be used.

[0237] Further, in the above-described embodiments, the printer is exemplified as the image forming apparatus but the present invention is not limited thereto. For example, other image forming apparatuses such as a copying machine, a facsimile machine, a multi-function machine having a combined function of these machines, and the like machine may also be used. A similar effect can be obtained by applying the present invention to these image forming apparatuses.

[0238] In the developer accommodating unit using the flexible container for accommodating the developer, it is possible to improve the unsealing characteristic of the sealing member for sealing the openings of the flexible container.