Electrophotographic image forming apparatus detachably mounting a developer replenishing container or in which a plurality of cartridges and developer replenishing containers are attachably and detachably positioned

[0002] 1. Field of the Invention

[0003] The present invention relates to an electrophotographic image forming apparatus.

[0004] An electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming process. Examples of electrophotographic image forming apparatus include an electrophotographic copier, an electrophotographic printer (an LED printer, a laser beam printer or the like), an electrophotographic facsimile device, an electrophotographic word processor, and the like.

[0005] 2. Related Background Art

[0006] In an electrophotographic image forming apparatus using an electrophotographic image forming process, a process cartridge system has been conventionally adopted in which an electrophotographic photosensitive drum and process means, which acts on the electrophotographic photosensitive drum, are integrally formed as a cartridge and the cartridge is detachably mountable to a main body of an electrophotographic image forming apparatus. According to the process cartridge system, maintenance of the apparatus can be performed by not a service man but a user himself and the operability can be significantly improved. Thus, the process cartridge system has been widely used in the electrophotographic image forming apparatus.

[0007] Further, a cartridge configuration, in which the respective process means are formed as a cartridge has been realized. For example, a developing cartridge in which a toner containing portion and developing means are integrally formed, or a process cartridge, in which an electrophotographic photosensitive member, charging means and cleaning means are integrally formed or the like, has been adopted.

[0008] The demand for a color electrophotographic image forming apparatus capable of forming a color image has recently increased, Thus, the introduction of a color electrophotographic image forming apparatus which can attain the following six objectives is expected:

[0009] (1) a low running cost;

[0010] (2) a compact size;

[0011] (3) low power consumption;

[0012] (4) high-quality image production;

[0013] (5) a high speed; and

[0014] (6) improved operability.

[0015] In these demands, for example, as a countermeasure for the item (1) a low running cost, a further increase in the life of the above-mentioned process means can be considered.

[0016] However, the amount of toner corresponding to the life of process means becomes an amount proportional to the life of the process means. For example, in a case where the life of process means is 50000 sheets of images, an amount of toner needed reaches 1.25 to 1.5 kg. When such a large amount of toner is integrally contained in a cartridge, the total weight and volume of the cartridge significantly become large and an operability may be lowered.

[0017] Further, since the space occupied by the entire cartridge is increased, miniaturization (downsizing) of the entire apparatus may become difficult. Further, a frame for supporting a cartridge with a large weight with high precision is needed and the total cost may increase.

[0018] The present invention has further advanced the above-mentioned conventional arts.

[0019] An object of the present invention is to provide an electrophotographic image forming apparatus in which a developer replenishing container containing a developer and a cartridge connectable to the developer replenishing container so as to allow the replenishment of the developer from the developer replenishing container can be each independently mounted in a main body of the electrophotographic image forming apparatus.

[0020] Another object of the present invention is to provide an electrophotographic image forming apparatus for forming an image on a recording medium, comprising: a container mounting means for attachably/detachably mounting a developer replenishing container having a developer containing portion for containing a developer and a discharge port for discharging the developer contained in the developer containing portion; and a cartridge mounting means for attachably/detachably mounting a cartridge having developing means for developing an electrostatic latent image formed on an electrophotographic photosensitive member using a developer, a developer containing portion for containing the developer to be used in developing with the developing means, and a developer receiving port for receiving the developer from the developer replenishing container into the developer containing portion, wherein the discharge port of the developer replenishing container and the developer receiving port of the cartridge are communicatively connected to each other in a state where the developer replenishing container and the cartridge are mounted in a main body of the electrophotographic image forming apparatus.

[0021] Another object of the present invention is to provide an electrophotographic image forming apparatus in which in a state where a developer replenishing container and a cartridge are mounted in a main body of the an electrophotographic image forming apparatus, a discharge port of the developer replenishing container and a developer receiving port of the cartridge are communicatively connected to each other so that the developer can be replenished from the developer replenishing container to the cartridge.

[0022] These and other objects, features and advantages of the present invention will become more apparent upon consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.

[0023] FIG. 1 is a cross-sectional view of an electrophotographic image forming apparatus of Embodiment 1;

[0024] FIG. 2 is a cross-sectional view of a process cartridge of Embodiment 1;

[0025] FIG. 3 is a cross-sectional view of a toner replenishing container of Embodiment 1;

[0026] FIG. 4 is a schematic external perspective view of the process cartridge of Embodiment 1;

[0027] FIG. 5 is a schematic external perspective view of the toner replenishing container of Embodiment 1;

[0028] FIG. 6 is a cross-sectional view of an engagement state (open state) between the process cartridge and the toner replenishing container of Embodiment 1;

[0029] FIG. 7 is a cross-sectional view of an engagement state (sealed state) between the process cartridge and the toner replenishing container of Embodiment 1;

[0030] FIG. 8 is a longitudinal cross-sectional view of an engagement state (open state) between the process cartridge and the toner replenishing container of Embodiment 1;

[0031] FIG. 9 is a detail (enlarged view of FIG. 8) of an open state of a cartridge opening and closing member and a toner replenishing container opening and closing member;

[0032] FIG. 10 is a longitudinal cross-sectional view of the process cartridge of Embodiment 1;

[0033] FIG. 11 is a schematic external perspective view of a main body of the electrophotographic image forming apparatus of Embodiment 1;

[0034] FIG. 12 is a schematic external perspective view of a process cartridge of Embodiment 2;

[0035] FIG. 13 is a schematic external perspective view of a toner replenishing container of Embodiment 2;

[0036] FIG. 14 is a cross-sectional view of an engagement state (open state) between the process cartridge and the toner replenishing container of Embodiment 2;

[0037] FIG. 15 is a cross-sectional view of an engagement state (sealed state) between the process cartridge and the toner replenishing container of Embodiment 2;

[0038] FIG. 16 is a schematic external perspective view of a toner replenishing container of Embodiment 3;

[0039] FIG. 17 is a cross-sectional view of an engagement state (open state) between a process cartridge and the toner replenishing container of Embodiment 3;

[0040] FIG. 18 is a cross-sectional view of an engagement state (sealed state) between the process cartridge and the toner replenishing container of Embodiment 3;

[0041] FIG. 19 is a schematic external perspective view (open state) of the process cartridge of Embodiment 1;

[0042] FIG. 20 is a schematic external perspective view (sealed state) of the process cartridge of Embodiment

[0043] FIG. 21 is an explanatory view of an engagement state (open state) between a cartridge opening and closing member, a toner replenishing container opening and closing member, and a discharge port portion;

[0044] FIG. 22 is an explanatory view of a state (sealed state) before the engagement of a toner replenishing container opening and closing member, and a discharge port portion;

[0045] FIG. 23 is an explanatory view of a state before the engagement of a cartridge opening and closing member, and a toner replenishing container opening and closing member;

[0046] FIG. 24 is a schematic external perspective view (sealed state) of a process cartridge of Embodiment 2;

[0047] FIG. 25 is a schematic external perspective view of a process cartridge of Embodiment 4;

[0048] FIG. 26 is a schematic external perspective view (open state) of the process cartridge of Embodiment 4;

[0049] FIG. 27 is a schematic external perspective view (sealed state) of the process cartridge of Embodiment 4;

[0050] FIG. 28 is a schematic external perspective view (open state) of a process cartridge of Embodiment 5;

[0051] FIG. 29 is a schematic external perspective view (sealed state) of the process cartridge of Embodiment 5;

[0052] FIG. 30 is a schematic perspective view of positioning of the toner replenishing container of Embodiment 1; and

[0053] FIG. 31 is a schematic view of positioning of a toner replenishing container of Embodiment 1;

[0054] Embodiments of the present invention will be described with reference to the drawings.

[0055] In the following descriptions, the longitudinal direction of a process cartridge is defined as a direction along which a process cartridge is mounted in a main body of an electrophotographic image forming apparatus, and is a direction which intersects (substantially at a right angle) a conveying direction of a recording medium. The longitudinal direction of the process cartridge is the same as the axial direction of an electrophotographic photosensitive member. Further, the left and right directions in this description are defined as the left and right directions when looking in the conveying direction of the recording medium. Further, the upper and lower positions are defined as the upper and lower directions in a cartridge-mounted state.

[0056] (Explanation of the entire electrophotographic image forming apparatus)

[0057] First, the entire configuration of a color electrophotographic image forming apparatus according to an embodiment of the present invention will be schematically described with reference to FIG. 1.

[0058] FIG. 1 is an explanatory view showing the entire configuration of a color laser beam printer which is an embodiment of a color toner electrophotographic image forming apparatus.

[0059] An image forming portion of an electrophotographic image forming apparatus (a color laser beam printer) shown in this embodiment is formed in such a manner that four process cartridges 9Y, 9M, 9C, 9K (yellow, magenta, cyan, black) each having a drum-shaped electrophotographic photosensitive member 7 (referred to as “photosensitive drum” below) and exposure means 1Y, 1M, 1C, 1K (laser beam optical scanning systems) corresponding to the respective colors, positioned above the process cartridges 9Y, 9M, 9C, 9K are juxtaposed to each other.

[0060] Below the above-mentioned image forming portion, feeding means 3 for feeding a recording medium 2, an intermediate transfer belt 4afor transferring a toner image formed on the photosensitive drum 7, and a secondary transfer roller 4dfor transferring a toner image on the intermediate transfer belt 4aonto the recording medium 2 are placed.

[0061] Also, fixing means 5 for fixing the recording medium 2 onto which a toner image has been transferred, and discharging means 3h, 3jfor discharging and stacking the recording medium 2 out of the apparatus, are placed.

[0062] The recording medium 2 includes, for example, a paper, an OHP sheet, a cloth or the like.

[0063] The image forming apparatus of the present embodiment of a cleanerless system. Thus, toner remaining on the photosensitive drum 7 after transfer is carried in developing means 10 later described and a cleaner specifically used for collecting and reserving toner remaining after transfer is not provided in the process cartridges 9Y, 9M, 9C, 9K.

[0064] Configurations of the respective portions of the above-mentioned image forming apparatus will be, in turn, described.

[0065] (Feeding portion)

[0066] The feeding portion (feeding means) 3 feeds the recording medium 2 to the image forming portion and mainly includes a feed cassette 3acontaining stacked sheets of recording medium 2, a feed roller 3b, an anti-double-feed retard roller 3c, a feed guide 3d, and a registration roller 3g.

[0067] The feed roller 3bis driven to rotate in accordance with an image forming operation and separates and feeds the recording medium 2 in the feed cassette 3afor every one sheet. The recording medium 2 is guided with the feed guide 3dand is conveyed to the registration roller 3gthrough conveying rollers 3e, 3f.

[0068] Just after the recording medium 2 is conveyed, the registration roller 3gis in a non-rotation mode. A skew feed of the recording medium 2 is corrected by hitting the leading end of the recording medium 2 to a nip portion of the registration roller 3g.

[0069] The registration roller 3gperforms a non-rotary operation for allowing the recording medium 2 to rest/wait and a rotary operation for conveying the recording medium 2 to the intermediate transfer belt 4aat a given sequence during image formation and registers between the toner image (developer image) during a transfer step that is a next step and the recording medium 2.

[0070] (Process cartridge)

[0071] In each of the process cartridges 9Y, 9M, 9C, 9K, the charging means 8 and the developing means 10 are placed around the photosensitive drum 7 as shown in FIG. 2 and they are integrally formed. The process cartridges 9Y, 9M, 9C, 9K can be easily detached by a user from the main body of the electrophotographic image forming apparatus (referred to as “apparatus body” below) 100 and when the photosensitive drum 7 is life-expired, it is replaced.

[0072] In the present embodiment, for example, the rotation number of the photosensitive drum 7 is counted, and when the number exceeds a given count number, an alarm indicates that the process cartridge is life-expired.

[0073] The photosensitive drum 7 in the present embodiment is of a negatively charged organic photoconductor. The photosensitive drum 7 has a photoconductive layer that is usually used, on an aluminum drum substrate having a diameter of about 30 mm and provides a charge injection layer on the outermost surface layer. And the photosensitive drum 7 is driven to rotate at a given process speed, about 117 mm/sec in this embodiment.

[0074] As the charge injection layer a coated layer of a material of an insulating resin binder into which, for example, SnO₂ultra fine particles are dispersed as conductive fine particles is used.

[0075] A drum flange 7bis fixed to that side end portion of the photosensitive drum 7 (see FIG. 10), and a non-driving flange 7dis fixed to this side end portion. A drum shaft 7ais penetrated through the centers of the drum flange 7band the non-driving flange 7d, and the drum shaft 7a, the drum flange 7band the non-driving flange 7dare integrally rotated. That is, the photosensitive drum 7 is rotated about the axis of the drum shaft 7a.

[0076] This side end portion of the drum shaft 7ais rotatably supported with a bearing 7e. The bearing 7eis fixed to a bearing case 7c. And the bearing case 7cis fixed to a frame 9dof the process cartridges 9Y, 9M, 9C, 9K.

[0077] (Charging means)

[0078] A charging means uses a contact charging method. In this embodiment, a magnetic brush charging device 8 using magnetic particles is used as a charging member.

[0079] The charging member concretely has a magnetic brush portion which is formed by magnetically confining conductive magnetic particles. The charging of the photoconductor is carried out by allowing the magnetic brush portion to contact the photosensitive drum 7 and applying a voltage to the charging member.

[0080] Such a charging method (charging of a member to be charged by directly injecting charges) is referred to as “an injection charging”. By using this injection charging method, a cleaner mechanism (cleaning blade, cleaning roller and the like) which mechanically scrapes off and removes toner remaining on the photosensitive drum 7 became unnecessary. This cleanerless system is described later.

[0081] The injection charging method of the present embodiment does not utilize the discharge phenomenon in which the charging to a member to be charged is carried out by the use of a corona charger. Accordingly, an applied charging bias required for charging is only a desired surface potential of a member to be charged, and the injection charging method is a perfect ozoneless type charging which does not generate ozone and a low power consumption type charging.

[0082] Next, the magnetic brush charging device 8 of the present embodiment will be described with reference to FIG. 2.

[0083] (Magnetic brush charging device)

[0084] The magnetic brush charging device 8 forms a magnetic brush layer of magnetic particles on a charging sleeve 8a, in which a magnet roller 8bis provided, and charges the photosensitive drum 7 to a desired potential through the contact portion of brush with the photosensitive drum 7.

[0085] The charging sleeve 8ais placed in such a manner that substantially a half left periphery of the charging sleeve 8ais protruded into an opening portion of a charging container 8econtaining magnetic particles in the longitudinal direction and substantially a half right periphery of the charging sleeve 8ais exposed outside. Irregularities are formed on a surface of the charging sleeve 8aby appropriately making the surface rough so that feeding of magnetic particles can be satisfactorily carried out.

[0086] The magnet roller 8bprovided within the charging sleeve 8ais four-pole polarized in the circumferential direction. And magnetic particles are adhered to the photosensitive drum 7 and in order to prevent the adhered magnetic particles from being carried during rotation of the drum, the magnet roller 8bis fixed so that one pole, specifically, a S1 pole is opposed to the central direction of the photosensitive drum 7.

[0087] A non-magnetic plate-shaped regulating blade 8cis placed with a given gap between this regulating blade 8cand the surface of the charging sleeve 8a. The regulating blade 8cis supported on the charging container 8ethrough a supporting metallic plate 8d. Magnetic particles are held by the magnet roller 8band are fed in a direction indicated by the arrow B by a rotation of the charging sleeve 8a. And the magnetic particles form a magnetic brush portion having a predetermined thickness on the charging sleeve 8aby the regulating blade 8c.

[0088] The charging sleeve 8ais oppositely placed with a given gap with respect to the photosensitive drum 7. The magnetic brush contacts the surface of the photosensitive drum 7 to form a charged nip portion. The width of the charged nip portion influences the charging properties for the photosensitive drum 7. In the present embodiment, the gap is controlled so that the width of the charged nip portion is of about 6 mm.

[0089] The charging sleeve 8ais driven to rotate with a motor (not shown) in a direction indicated by the arrow B in FIG. 2, which is a counter direction at the opposed portion with respect to the photosensitive drum 7 that is a member to be charged. In the present embodiment, when the rotary speed of the photosensitive drum 7 is V₁, the charging sleeve 8ais rotated at a speed ratio of V₂≅1.5×V₁in the counter direction. The larger the relative rotary speed between the photosensitive drum 7 and the magnet brush portion becomes, the more the chance of contact increases. Accordingly, the charging uniformity is enhanced and the uptake properties of toner remaining after transfer to the magnetic brush can be enhanced.

[0090] To the magnetic brush portion is applied a desired charging bias from a charging bias power supply (not shown) through the charging sleeve 8a, and the surface of the photosensitive drum 7 is contact-charging treated to a desired polarity and potential in the charged nip portion.

[0091] As conductive magnetic particles forming the magnetic brush portion, magnetic metallic particles such as ferrite, magnetite and the like, and also such conductive magnetic particles bonded with resin can be used.

[0092] An agitating member 8fis rotatably supported between wall surfaces of both ends of the charging container 8ein the longitudinal direction so that it is placed substantially parallel with the charging sleeve 8aand above the charging sleeve 8a.

[0093] A charging brush 8gcontacts the surface of photosensitive drum 7 at an inroad amount of about 1 mm and applies a desired voltage thereto. By the contact of the charging brush 8g, the toner remaining on the surface of the photosensitive drum 7 is uniformly dispersed, and a residual charge elimination is further performed, whereby the charging of the next step is uniformly carried out.

[0094] Next, a cleanerless system in the reversal developing system in which the photosensitive member is negatively charged and the negatively charged toner is developed on a lower potential portion of an exposure portion will be described.

[0095] (Cleanerless system)

[0096] First, particularly, a positively charged toner among the toner slightly remaining after transfer on the photosensitive member is once electrostatically drawn in the magnetic brush charging device 8 and toner other than the above-mentioned toner is also collected by forcible scraping using a brush. And after the toner is negatively charged by friction with magnetic particles in the magnetic brush charging device 8, the toner is vomited onto the photosensitive drum 7.

[0097] On the other hand, the toner remained negatively charged among the toner remaining after transfer is not almost drawn in the magnetic brush charging device 8 and is collected in the developing device 10 together with toner vomited from the magnetic brush charging device 8 (cleaning simultaneous with developing).

[0098] The drawing of toner into the developing device 10 in the cleaning simultaneous with developing is carried out by the fog removal bias (the fog removal potential difference is the potential difference between the direct current voltage applied to the developing device 10 and the surface potential of the photosensitive drum 7).

[0099] According to this method, since a part of the toner remaining after transfer is via the magnetic brush charging device 8 collected and the remainder is directly collected in the developing device 10 so that the toner remaining after transfer is used in the next step and thereafter, the elimination of waste toner becomes possible and the inconvenience of maintenance can be decreased. Further, a cleanerless system uses less space, whereby the image informing apparatus can be significantly reduced in size.

[0100] (Exposure means)

[0101] In the present embodiment, exposure to the above-mentioned photosensitive drum 7 is carried out by the use of laser exposure means 1Y, 1M, 1C, 1K. That is, when an image signal is transmitted from the apparatus body 100, a laser beam L modulated in response to this signal is applied to the uniformly charged surface of the photosensitive drum 7 by scanning (see FIG. 6). And an electrostatic latent image corresponding to the image information is selectively formed on the surface of the photosensitive drum 7.

[0102] Each of the laser exposure means 1Y, 1M, 1C, 1K is composed of a solid-state laser element (not shown), a polygon mirror 1a, an imaging lens 1b, a reflective mirror 1cand the like. The solid-state laser element is ON/OFF light emission controlled at a desired timing with an light emission signal generator (not shown) based on the inputted image signal. The laser beam L emitted from the solid-state laser element is converted into a substantially parallel beam with a collimator lens system (not shown) and is scanned with the polygon mirror 1awhich is rotated at a high speed. And the beam is imaged on the photosensitive drum 7 in a spot shape through the imaging lens 1band the reflective mirror 1c.

[0103] Thus, the laser beam scanning exposure in the main scanning direction and the exposure in the sub-scanning direction due to the rotation of the photosensitive drum 7 are applied onto the surface of the photosensitive drum 7 to thereby obtain an exposure distribution in accordance with the image signal.

[0104] That is, by the irradiation and non-irradiation of laser beam L are generated a surface potential, a reduced highlight potential, and a surface potential non-reduced shadow potential, respectively. And by contrast between the highlight potential and the shadow potential an electrostatic latent image corresponding to the image information is formed.

[0105] (Developing means)

[0106] The developing device 10, which is developing means, is a two-component contact developing device (two-component magnetic brush developing device) and holds a developer composed of a carrier and a toner on a developing sleeve 10a, which is a developer bearing member, in which a magnet roller 10bis provided. The developing sleeve 10ais provided with a regulating blade 10cwith a desired gap therebetween. By the rotation of the developing sleeve 10ain a direction indicated by an arrow C, a thin layer of the developer is formed on the developing sleeve 10a. The regulating blade 10cis supported and fixed to a developing container 10f.

[0107] The developing sleeve 10ais set in such a manner that it is placed in parallel so as to have a desired gap between the developing sleeve 10aand the photosensitive drum 7 and in such a manner that during developing, a developer formed on the developing sleeve 10acan develop in a state where the developer contacts the photosensitive drum 7. The developing sleeve 10ais driven to rotate at a desired peripheral speed in a counterclockwise indicated by an arrow, which is a counter direction to the rotation direction of the photosensitive drum 7 in the developing portion.

[0108] The toner used in the present embodiment is a negatively charged toner with an average particle diameter of 6 μm. As a magnetic carrier, a magnetic carrier having a saturated magnetization of 205 emu/cm³and an average particle diameter of 35 μm is used. Further, as a developer, a mixture of toner and carrier mixed at the weight ratio of 6:94 is used.

[0109] A developer containing portion 10hin which a developer is circulated is divided into two portions with a partition wall 10dextending in the longitudinal direction except for both end portions of the developer containing portion 10h, as shown in FIGS. 2 and 10. And agitating screws 10eA, 10eB are placed so as to sandwich the partition wall 10d. The agitating screws 10eA, 10eB are rotatably supported on both side surfaces of the frame 9dof each of the process cartridges 9Y, 9M, 9C, 9K through bearings 10j.

[0110] The toner replenished from toner replenishing containers 12Y, 12M, 12C, 12K used as the developer replenishing containers falls down on this side of the agitating screw 10eB and is agitated while being fed to that side in the longitudinal direction and is passed through a portion 10d1 without the partition wall 10don that side end. Then the toner is further fed to this side in the longitudinal direction with the agitating screw 10eA and is passed through a portion 10d2 without the partition wall 10don this side and is agitated while being fed with the agitating screw 10eB. Thus, the circulation is repeated.

[0111] Developing steps of visualizing an electrostatic latent image formed on the photosensitive drum 7 by the two-component magnetic brush process using the developing device 10 and the circulation system of developer will be described.

[0112] By the rotation of the developing sleeve 10a, a developer in a developing container 10fis drawn to the surface of the developing sleeve 10awith the N3 pole of the magnet roller 10band is fed.

[0113] In the process of feeding the developer, the layer thickness of developer is regulated with the regulating blade 10cplaced vertically to the developing sleeve 10a, and a thin layered developer is formed on the developing sleeve 10a. When the thin layered developer is fed to a developing pole, the N1 pole corresponding to the developing portion, a magnetic brush is formed by magnetic force. An electrostatic latent image on the surface of the photosensitive drum 7 is developed by toner in a developer which stands like the ears of rise as a toner image. The electrostatic latent image is developed while reversed in the present embodiment.

[0114] A thin layered developer on the developing sleeve 10a, which has passed through the developing portion is subsequently fed into the developing container 10fby the rotation of the developing sleeve 10aand is left from the surface of the developing sleeve 10aby the repulsion magnetic field in the N2 pole and the N3 pole to return to a developer reservoir in the developing container 10f.

[0115] A direct current (DC) voltage and an alternating current (AC) voltage are applied from a power supply (not shown) to the developing sleeve 10a. In the present embodiment a DC voltage of −500 V and an AC voltage of peak-to-peak voltage of 1500 V at the frequency of 2000 Hz are applied to selectively develop only the exposed portion of photosensitive drum 7.

[0116] When the AC voltage is applied in the two-component developing process, the developing efficiency is generally increased to obtain an image having high quality. However, there arises a fear that fogging may easily occur. Therefore, prevention of the fogging is usually realized by providing the potential difference between the DC voltage applied to the developing sleeve 10aand the surface potential of the photosensitive drum 7. More specifically, the bias voltage of a potential difference between the potential of the exposed portion and the potential of the non-exposed portion of the photosensitive drum 7 is applied.

[0117] The potential difference for preventing fogging is called a fogging removal potential (V_back). By the potential difference, adhesion of toner to a non-image area (non-exposed portion) of the surface of the photosensitive drum 7 can be prevented during developing and the residual toner remaining on the surface of the photosensitive drum 7 after transfer is collected in the cleanerless system device (cleaning simultaneous with developing).

[0118] When toner is consumed by developing, the toner density in a developer is decreased. In the present embodiment a sensor 10gwhich detects the toner density is placed at a position in the vicinity of the outer periphery surface of the agitating screw 10eB. When the sensor 10gdetects that the toner density in the developer is further decreased than a desired density level, an instruction to replenish toner from the toner replenishing containers 12Y, 12M, 12C, 12K to the developing device 10 is issued. By this toner replenishing operation the toner density in the developer can be always maintained and controlled at a desired level.

[0119] (Toner replenishing container)

[0120] The configuration of a toner replenishing container according to the present embodiment will be described with reference to FIG. 1, FIG. 3, FIG. 5, FIG. 8, FIG. 9 and FIG. 11.

[0121] The toner replenishing containers 12Y, 12M, 12C, 12K are placed above the process cartridges 9Y, 9M, 9C, 9K in parallel to each other and are mounted from the front side of the apparatus body 100 (see FIG. 11).

[0122] Each of the toner replenishing containers 12Y, 12M, 12C, 12K has a toner containing portion 12kused as a developer containing portion, which contains toner in a frame 12r, as shown in FIG. 3. In the toner containing portion 12kare placed an agitating plate 12bused as a feeding member and fixed to an agitating shaft 12c, and a screw 12aused as a rotary member. And a discharge port portion 12fused as a discharge port and having a port 12f1 for discharging toner is formed on the bottom of the container. The screw 12aand the agitating shaft 12care rotatably supported with bearings 12din both ends thereof. A drive coupling (concave) 12eis placed on the one tip end. The drive coupling (concave) 12ereceives driving transmission from a drive coupling (convex) 24 of the apparatus body 100 and is driven to rotate.

[0123] The outside portion of the screw 12ahas a spiral lib shape and the twist direction of the spiral shape is reversed while setting the discharge port portion 12fas the center (see FIG. 9). By the rotation of the drive coupling (convex) 24, the screw 12ais rotated in a desired rotational direction. Toner is then fed toward the discharge port portion 12fand freely falls down from the port of the discharge port portion 12f, to thereby replenish toner in each of the process cartridges 9Y, 9M, 9C, 9K.

[0124] The distal end of the agitating plate 12bin the radial direction of rotation is slanted (see FIG. 8). When the distal end is brought into contact with the inner wall surface (the inner wall surface of a toner containing portion 12k) of each of the toner replenishing containers 12Y, 12M, 12C, 12K, it contacts the surface at an angle. Specifically, the distal end side of the agitating plate 12bis twisted to become spiral-shape. Thus, by the twist inclination on the distal end side of the agitating plate 12bis generated the feeding force in the axial direction of the agitating shaft 12cso that toner is fed in the longitudinal direction.

[0125] (Transfer means)

[0126] An intermediate transfer unit 4, which is a transfer means, secondarily transfers a plurality of toner images collectively, which have been sequentially primarily transferred from the photosensitive drums 7 and superimposed on one another to the recording medium 2. As shown in FIG. 1, the intermediate transfer unit 4 is provided with an intermediate transfer belt 4arunning in a direction indicated by an arrow, and the intermediate transfer belt 4aruns clockwise at a peripheral speed substantially the same as the outer peripheral speed of the photosensitive drum 7. The intermediate transfer belt 4ais an endless belt with a circumferential length of about 940 mm, and is extended around three rollers of a drive roller 4b, a secondary transfer opposed roller 4g, and a driven roller 4c. Further, transfer charging rollers 4fY, 4fM, 4fC, 4fK are rotatably placed at positions respectively opposed to the photosensitive drums 7 and are pressurized in the respective central directions of the photosensitive drums 7.

[0127] The transfer charging rollers 4fY, 4fM, 4fC, 4fK are energized from a high voltage power supply (not shown) to perform charging with polarity opposite to that of toner from the back side of the intermediate transfer belt 4aand primarily transfer the toner images on the photosensitive drums 7 to the upper surface of the intermediate transfer belt 4asequentially.

[0128] A secondary transfer roller 4d, which is used as a transfer member, is in press-contact with the intermediate transfer belt 4aat a position opposed to the secondary transfer opposed roller 4gin the secondary transfer portion. The secondary transfer roller 4dcan perform up-and-down motion in FIG. 1 and is also rotated. At this time bias is simultaneously applied to the secondary transfer roller 4d, so that the toner image on the intermediate transfer belt 4ais transferred to the recording medium 2.

[0129] In this step the intermediate transfer belt 4aand the secondary transfer roller 4dare respectively driven. When the recording medium 2 enters the secondary transfer portion, a given bias is applied to the secondary transfer roller 4dand the toner image on the intermediate transfer belt 4ais secondarily transferred to the recording medium 2.

[0130] While the secondary transfer with the recording medium sandwiched between the intermediate transfer belt 4aand the secondary transfer roller 4dis performed, the recording medium is fed at a given speed leftward in the drawing to a fixing device 5, which is the next step.

[0131] At a given position on the intermediate transfer belt 4aon the most downstream side in the transfer process is provided a cleaning unit 11 contactable with and separable from the surface of the intermediate transfer belt 4a. The cleaning unit 11 removes toner remaining after the secondary transfer.

[0132] A cleaning blade 11afor removing the toner remaining after the secondary transfer is placed in the cleaning unit 11. The cleaning unit 11 is swingably mounted at the rotation center (not shown). The cleaning blade 11ais in press-contact with the intermediate transfer belt 4ain an inroading direction. The transfer residual toner drawn into the cleaning unit 11 is fed to a waste toner tank (not shown) with a feeding screw 11bto be stored therein.

[0133] As the intermediate transfer belt 4a, an intermediate transfer belt made of polyimide resin can be used. The material of the intermediate transfer belt 4ais not limited to the polyimide resin, and plastics such as polycarbonate resin, polyethylene terephthalate resin, polyvinylidene fluoride resin, polyethylene naphthalate resin, polyether ether ketone resin, polyether sulfone resin, and polyurethane resin, and fluorine series rubber and silicone series rubber can be preferably used.

[0134] (Fixing portion)

[0135] A toner image formed on the photosensitive drum 7 with the developing means 10 is transferred to the recording medium 2 through the intermediate transfer belt 4a. Then the fixing device 5 fixes the toner image transferred to the recording medium 2 with heat.

[0136] As shown in FIG. 1, the fixing device 5 is provided with a fixing roller 5afor imparting heat to the recording medium 2 and a pressure roller 5bfor press-contacting the recording medium 2 with the fixing roller 5a. Each of the rollers 5a, 5bis a hollow roller and has a heater (not shown) therein. The rollers are driven and rotated to feed the recording medium simultaneously.

[0137] That is, the recording medium 2 holding the toner image is fed with the fixing roller 5aand the pressure roller 5band at the same time the toner image is fixed to the recording medium 2 by applying heat and pressure. The fixed recording medium 2 is discharged through discharge rollers 3h, 3jand is stacked on a tray 6 on the apparatus body 100.

[0138] (Mounting of process cartridge and toner replenishing container)

[0139] Next, mounting procedures of the process cartridge and the toner replenishing container will be described with reference to FIG. 6, FIG. 8, FIG. 10 and FIG. 11.

[0140] As shown in FIG. 11, an openable front door 27 is provided in the front of the apparatus body 100. The front door 27 is openable and closable in a direction indicated by the double-headed arrow. When the front door 27 is opened on this side, ports 100a, 100bfor separately inserting the process cartridges 9Y, 9M, 9C, 9K and the toner replenishing containers 12Y, 12M, 12C, 12K are exposed.

[0141] A pivotably supported centering plate 25 is placed on the port 100bfor inserting the process cartridges 9Y, 9M, 9C, 9K. The centering plate 25 is pivotable in a direction indicated by the double-headed arrow. When the process cartridges 9Y, 9M, 9C, 9K are inserted or removed, the centering plate 25 is first opened before the insertion or the removal.

[0142] In the apparatus body 100, as shown in FIG. 6, guide rails 21 which are used as cartridge mounting means serving as a guide for detachably mounting the process cartridges 9Y, 9M, 9C, 9K, and a guide rail 20 which is used as container mounting means serving as a guide for detachably mounting the toner replenishing containers 12Y, 12M, 12C, 12K, are fixed.

[0143] A direction of mounting the process cartridges 9Y, 9M, 9C, 9K is parallel to the axial direction of the photosensitive drum 7, and a direction of mounting the toner replenishing containers 12Y, 12M, 12C, 12K is parallel to the axial direction of the screw 12a. The guide rails 21, 20 are placed in the same direction as the mounting direction. The process cartridges 9Y, 9M, 9C, 9K and the toner replenishing containers 12Y, 12M, 12C, 12K are slid and inserted from this side in the apparatus body 100 to that side along the guide rails 21, 20.

[0144] When the process cartridges 9Y, 9M, 9C, 9K are completely inserted into that side, the drum shaft 7aon that side end is inserted into a centering shaft 26 of the apparatus body 100, and the center position of rotation on that side of the photosensitive drum 7 is determined with respect to the apparatus body 100. At the same time, a drum flange 7band a drive coupling (convex) 24 are connected to each other so that the photosensitive drum 7 can be driven and rotated. Further, a support pin 22 for positioning the process cartridges 9Y, 9M, 9C, 9K is arranged on a back side plate 23. This support pin 22 is inserted into a concave portion 9d1 provided on the frame 9dof the process cartridges 9Y, 9M, 9C, 9K so that the position of the frame 9dof each of the process cartridges 9Y, 9M, 9C, 9K is fixed.

[0145] The pivotable centering plate 25 is placed on this side of the apparatus body 100. A bearing case 7cof each of the process cartridges 9Y, 9M, 9C, 9K is supported and fixed to this centering plate 25. By such a series of inserting operations, the photosensitive drums 7 and the process cartridges 9Y, 9M, 9C, 9K can be positioned with respect to the apparatus body 100.

[0146] Therefore, the drum shaft 7a, drum flange 7b, concave portion 9d1, and bearing case 7cform a positioning portion for positioning each of the process cartridges 9Y, 9M, 9C, 9K with respect to the apparatus body 100.

[0147] On the other hand, when the toner replenishing containers 12Y, 12M, 12C, 12K are completely inserted to that side as shown in FIG. 8, the support pin 22 protruding from the back side plate 23 is inserted into a concave portion 12r1 provided on that side wall surface of a frame 12r, whereby the position of the frame 12rof the toner replenishing containers 12Y, 12M, 12C, 12K is fixed. At the same time, a drive coupling (concave) 12eand the drive coupling (convex) 24 are connected to each other and the screw 12aand the agitating shaft 12ccan be driven and rotated.

[0148] Further, as shown in FIGS. 30 and 31, a plurality of protrusions 12pare formed on this side wall surface of the frame 12rof each of the toner replenishing containers 12Y, 12M, 12C, 12K. These protrusions 12pengage with the inner wall of the opening portion of the guide rail 20. And the engagement of the opening portion of the guide rail 20 with the protrusions 12pdetermines this side position of the toner replenishing containers 12Y, 12M, 12C, 12K.

[0149] Therefore, the support pin 22, the drive coupling (concave) 12e, and the protrusions 12pform a positioning portion for positioning the toner replenishing containers 12Y, 12M, 12C, 12K with respect to the apparatus body 100.

[0150] (Explanation of the structure for replenishing toner)

[0151] First, configurations of a replenishing port portion of the process cartridge and the cartridge opening and closing member will be described with reference to FIG. 2, FIG. 4, FIG. 19. FIG. 20, and FIG. 23.

[0152] As shown in FIG. 2 and FIG. 4, on the upper surface of a frame 9dforming a part of each of the process cartridges 9Y, 9M, 9C, 9K is placed a replenishing port portion 9cwhich is used as an developer receiving port or an opening for receiving toner from the toner replenishing containers 12Y, 12M, 12C, 12K. In this embodiment the replenishing port portion 9cis placed on that side (near the forefront) in a direction of inserting the process cartridges 9Y, 9M, 9C, 9K, that is on the drive transmission side of the photosensitive drum 7.

[0153] In the periphery of the replenishing port portion 9c, a sealing member 9ais adhered and fixed to the upper surface of the frame 9d. In the sealing member 9aan opening 9a1 having the same shape of the replenishing port portion (opening) 9cis formed. A guide rib 9eand a cartridge opening and closing member 9bare placed on the frame 9don the drive input side for driving the developing device 10 (on that side in the direction of inserting the process cartridge). The guide rib 9eis extended in a direction perpendicular to the axial direction of the developing sleeve 10a. The cartridge opening and closing member 9bslidably engages with the guide rib 9e.

[0154] Before use of the process cartridges 9Y, 9M, 9C, 9K, the sealing member 9afor the replenishing port portion 9cclosely contacts to the cartridge opening and closing member 9band the opening 9a1 is closed (see FIG. 2).

[0155] The first cartridge engagement portion (concave) 9hand the second cartridge engagement portion (convex) 9jare formed on the cartridge opening and closing member 9bas shown in FIG. 4 and FIG. 23.

[0156] In this embodiment, a convex rib on the uppermost surface is the second cartridge engagement portion (convex) 9j, and a concave portion perpendicular to the above-mentioned convex portion 9jis the first cartridge engagement portion (concave) 9h. Note that the second cartridge engagement portion (convex) 9jis extended in a direction perpendicular to the axial direction of the developing sleeve 10a, and the first cartridge engagement portion (concave) 9his extended in the axial direction of the developing sleeve 10a.

[0157] In the cartridge opening and closing member 9ban opening 9ffor communicating the replenishing port portion 9cwith an opening 12f1 of the discharge port 12fof the toner replenishing containers 12Y, 12M, 12C, 12K is provided. Further, a rack 9gwhich is used as a release portion is integrally formed in the cartridge opening and closing member 9b. The rack 9greceives a driving force from an opening and closing gear (large) 13bused as a driving member and placed in the apparatus body 100, as shown in FIG. 20.

[0158] As shown in FIG. 20, a rotary shaft 13aof the opening and closing gear 13bis placed above each of the process cartridges 9Y, 9M, 9C, 9K, in parallel to the axis of the photosensitive drum 7. The above-mentioned opening and closing gear (large) 13bis fixed to the end of the rotary shaft 13aon that side. To the end of this side of the rotary shaft 13ais fixed a rotary lever 13c. Further, the rotary shaft 13ais rotatably supported with a bearing (not shown) in the apparatus body 100.

[0159] When the rotary lever 13cis rotated, the opening and closing gear (large) 13bis rotated through the rotary shaft 13awhile interlocked therewith. Then, when each of the process cartridges 9Y, 9M, 9C, 9K is inserted into the apparatus body 100 and is set at a given position, the opening and closing gear (large) 13bengages with the teeth of rack 9gat a given phase, as shown in FIG. 9. And by the rotary driving of the opening and closing gear (large) 13b, the rack 9greceives a driving force and is slid in the axial direction of guide rib 9e(a direction perpendicular to the axial direction of the developing sleeve 10a).

[0160] In a state where the process cartridges 9Y, 9M, 9C, 9K are set in the apparatus body 100, when the rotary lever 13cis rotated clockwise, the cartridge opening and closing member 9bis slid leftward through the rotary shaft 13aand the opening and closing gear (large) 13b(see FIG. 19). When the rotary lever 13cis rotated counterclockwise under this state, the cartridge opening and closing member 9bis slid rightward and is returned to the original position (see FIG. 20). That is, by the rotation of the rotary lever 13cthe cartridge opening and closing member 9bis slid in a direction perpendicular to the axial direction of the developing sleeve 10aso that it moves freely between the first position (released or opened position (see FIG. 19)) which opens the replenishing port portion 9cand the second position (sealed or closed position (see FIG. 20)) which closes or seals the replenishing port portion 9c.

[0161] Next, configurations of a discharge port of the toner replenishing container and a toner replenishing container opening and closing member will be described with reference to FIG. 3, FIG. 5, FIG. 9, FIG. 21, and FIG. 22.

[0162] In a part of the bottom of the toner replenishing containers 12Y, 12M, 12C, 12K is provided the discharge port portion 12ffor discharging toner outside the container, as shown in FIG. 3 and FIG. 5. At the center of the discharge port portion 12fis formed an opening 12f1 for a discharge port. A sealing member 12gis adhered to the bottom portion of each of the toner replenishing containers 12Y, 12M, 12C, 12K so as to surround the periphery of the opening 12f1. In this embodiment, the discharge port portion 12fis placed on that side of each of the toner replenishing containers 12Y, 12M, 12C, 12K (near the forefront in a direction of inserting the containers into the apparatus body 100) which is on the drive transmission side of the screw 12a.

[0163] As shown in FIG. 3, FIG. 5, and FIG. 22, in the periphery of the discharge port portion 12fon the bottom of each of the toner replenishing containers 12Y, 12M, 12C, 12K are formed the first toner replenishing container engagement portion (convex) 12hand the second toner replenishing container engagement portion (concave) 12jused as a replenishing container engagement portion. The toner replenishing container engagement portions 12h, 12jform an integral rail with concave and convex portions combined, which is extended in a direction perpendicular to the axial direction of the developing sleeve 10a. In this embodiment, a convex rib on the lowermost surface is the first toner replenishing container engagement portion (convex) 12hand a concave portion just above the convex rib is the second toner replenishing container engagement portion (concave) 12j.

[0164] A toner replenishing container opening and closing member 14 used as a replenishing container opening and closing member engages with the discharge port portion 12fon the lower side of the discharge port portion 12f, that is, the drive input side for driving the agitating plate 12b(that side in a direction of inserting the toner replenishing container) so that a port 12f1 can be opened and closed. Thus, the toner replenishing container opening and closing member 14 can be moved between the first position (opened or released position) for opening the port 12f1 of the discharge port portion 12fand the second position (sealed or closed position) for sealing and closing the port 12f1.

[0165] In the toner replenishing container opening and closing member 14 are formed a first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container and a second driving force receiving portion 14b(concave) for opening and closing the toner replenishing container, which are used as driving force receiving portions as shown in FIG. 5. In this embodiment, a concave rib on the uppermost surface is the second driving force receiving portion 14b(concave) for opening and closing the toner replenishing container, and a convex rib perpendicular to the concave rib is the first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container. Note that the second driving force receiving portion 14b(concave) for opening and closing the toner replenishing container is extended in a direction perpendicular to the axial direction of the screw 12a, and the first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container is extended in the axial direction of the screw 12ato protrude downward (on the process cartridge side).

[0166] The toner replenishing container opening and closing member 14 is slid in a direction perpendicular to the axial direction of the screw 12awith respect to the discharge port portion 12fof the toner replenishing containers 12Y, 12M, 12C, 12K, by inserting the above-mentioned second driving force receiving portion 14b(concave) for opening and closing the toner replenishing container onto the first toner replenishing engagement portion (convex) 12hof the toner replenishing containers 12Y, 12M, 12C, 12K (see FIG. 21 and FIG. 22). Accordingly, the toner replenishing container opening and closing member 14 can be moved between the first position for opening the port 12f1 of the discharge port portion 12f1 and the second position for sealing or closing the port 12f1.

[0167] Next, toner replenishing from the toner replenishing container to the process cartridge will be described with reference to FIG. 6, FIG. 7, FIG. 8. FIG. 9, FIG. 21, FIG. 22, and FIG. 23.

[0168] Here, a case where the process cartridges 9Y, 9M, 9C, 9K are inserted in the apparatus body 100, and then the toner replenishing containers 12Y, 12M, 12C, 12K are inserted therein (see FIG. 8).

[0169] As shown in FIG. 7 and FIG. 23, when the toner replenishing containers 12Y, 12M, 12C, 12K are inserted into the apparatus body 100, the first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container of the toner replenishing container opening and closing member 14 is inserted and engages with the first cartridge engagement portion (concave) 9hof the cartridge opening and closing member 9b. The engagement relationship is the same as in the case where the toner replenishing containers 12Y, 12M, 12C, 12K are first inserted into the apparatus body 100 and then the process cartridges 9Y, 9M, 9C, 9K are inserted therein.

[0170] In this engagement state, that is, the state where the process cartridges 9Y, 9M, 9C, 9K and the toner replenishing containers 12Y, 12M, 12C, 12K are inserted in the apparatus body 100, the cartridge opening and closing member 9bis at the second position for sealing or closing the replenishing port portion 9c, and the toner replenishing container opening and closing member 14 is at the second position for sealing or closing the port 12f1 of the discharge port portion 12f. And in a state where the cartridge opening and closing member 9bis at the second position the rack 9gengages with the opening and closing gear 13b(see FIG. 20). In this engagement state, when the rotary lever 13cis rotated clockwise, the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are integrally moved in the left direction (a direction perpendicular to the axial direction of the developing sleeve 10a) (see FIG. 6). And when the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are moved from the respective second positions to the respective first positions, the port 12f1 of the discharge port portion 12fof the toner replenishing containers 12Y, 12M, 12C, 12K and the replenishing port portion 9cof the process cartridges 9Y, 9M, 9C, 9K are communicated through the opening 9fof the cartridge opening and closing member 9bso that the respective toner replenishing from the toner replenishing containers 12Y, 12M, 12C, 12K to the process cartridges 9Y, 9M, 9C, 9K is made.

[0171] On the other hand, simultaneously or a short time later when the toner replenishing container opening and closing member 14 is moved, the second cartridge engagement portion (convex) 9jof the cartridge opening and closing member 9bis inserted into and engages with the second toner replenishing container engagement portion (concave) 12jof the discharge port portion 12fof each of the toner replenishing containers 12Y, 12M, 12C, 12K (see FIG. 21 and FIG. 22).

[0172] That is, by the engagement of the second cartridge engagement portion (convex) 9jwith the second toner replenishing container engagement portion (concave) 12j, a position of the cartridge opening and closing member 9bin the height direction with respect to the discharge port portion 12fof the toner replenishing containers 12Y, 12M, 12C, 12K can be correctly determined. And the sealing member 12gplaced on the toner replenishing container 12Y, 12M, 12C, 12K side closely contacts to the cartridge opening and closing member 9b. Accordingly, the toner leakage during replenishing can be preferably prevented.

[0173] Next, a toner replenishing structure of Embodiment 2 will be described with reference to FIG. 12, FIG. 13, FIG. 14, and FIG. 15. Note that the same components as in Embodiment 1 are denoted by the same reference numerals. Thus, components different from those in Embodiment 1 will be described.

[0174] The point in this embodiment, significantly different from Embodiment 1 is that, in contrast with Embodiment 1 where the drive transmission means such as the opening and closing gear (large) 13band the opening and closing lever 13cfor opening and closing the opening 9fwith the cartridge opening and closing member 9bis placed on the apparatus body 100, in Embodiment 2 the drive transmission means is placed on the toner replenishing container 12Y, 12M, 12c, 12K.

[0175] These arrangement configurations will be described in detail.

[0176] The replenishing port portion 9cof each of the process cartridges 9Y, 9M, 9C, 9K is placed on this side in a direction of inserting the process cartridges 9Y, 9M, 9C, 9K, which is the non-driving side of the photosensitive drum 7 (see FIG. 12). On the other hand, the discharge port portion 12fof each of the toner replenishing containers 12Y, 12M, 12C, 12K is placed on this side in the direction of inserting the process cartridges 9Y, 9M, 9C, 9K in correspondence to the replenishing port portion 9c(see FIG. 13). Further, a rotary lever 12mis rotatably placed on this side surface of each of the toner replenishing containers 12Y, 12M, 12C, 12K. And the rotary lever 12mis provided with a gear 12nas a driving member.

[0177] Here, a case where the toner replenishing containers 12Y, 12M, 12C, 12K are inserted in a state where the process cartridges 9Y, 9M, 9C, 9K have already been inserted in the apparatus body 100, will be described.

[0178] When the toner replenishing containers 12Y, 12M, 12C, 12K are inserted in the apparatus body 100, as shown in FIG. 15, the first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container of the toner replenishing container opening and closing member 14 is inserted into and engages with the first cartridge engagement portion (concave) 9hof the cartridge opening and closing member 9b, that is in the second position sealing the replenishing port portion 9c. This engagement relationship is the same as in the case where the toner replenishing containers 12Y, 12M, 12C, 12K are first inserted in the apparatus body 100 and then the process cartridges 9Y, 9M, 9C, 9K are inserted therein. Further at this time, the gear 12nprovided on the rotary lever 12mof each of the toner replenishing containers 12Y, 12M, 12C, 12K is inserted into and engages with the rack 9gof the cartridge opening and closing member 9b.

[0179] In this state, when the rotary lever 12mis rotated clockwise, the rotation drive of the gear 12nis transmitted to the cartridge opening and closing member 9bthrough the rack 9g.

[0180] At this time, in the same manner as described in Embodiment 1, the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are integrally moved in the left direction (see FIG. 14). And when the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are moved from the respective second positions to the respective first positions, as shown in FIG. 14, the port 12f1 of the discharge port portion 12fof the toner replenishing containers 12Y, 12M, 12C, 12K and the replenishing port portion 9cof the process cartridges 9Y, 9M, 9C, 9K are communicated with each other through the opening 9fof the cartridge opening and closing member 9bso that the toner replenishing from the toner replenishing containers 12Y, 12M, 12C, 12K to the process cartridges 9Y, 9M, 9C, 9K is made.

[0181] Next, a toner replenishing structure of Embodiment 3 will be described with reference to FIG. 16, FIG. 17, FIG. 18, and FIG. 24. Note that the same components as in Embodiment 1 are denoted by the same reference numerals. Thus, components different from those in Embodiment 1 will be described.

[0182] The point in this embodiment, significantly different from Embodiment 1 is that, in contrast with Embodiment 1 where the drive transmission means such as the opening and closing gear (large) 13band the opening and closing lever 13cfor opening and closing the opening 9fwith the cartridge opening and closing member 9bis placed on the apparatus body 100, in Embodiment 3, the drive transmission means is placed on each of the toner replenishing container 12Y, 12M, 12C, 12K. Further, points in this embodiment significantly different from Embodiment 2 are that, in contrast with Embodiment 2 where the replenishing port portion 9cof each of the process cartridges 9Y, 9M, 9C, 9K and the discharge port portion 12fof each of the toner replenishing containers 12Y, 12M, 12C, 12K are placed on this side in the direction of inserting the process cartridges 9Y, 9M, 9C and 9K, in this Embodiment, they are placed on that side in the direction of inserting the process cartridges 9Y, 9M, 9C, 9K, as in Embodiment 1.

[0183] These arrangement configurations will be described in detail.

[0184] As shown in FIG. 16, the rotary lever 12mis rotatably placed on this side surface of each of the toner replenishing containers 12Y, 12M, 12C, 12K. And the rotary lever 12mis provided with a gear 12n. On the other hand, on the apparatus body 100, as shown in FIG. 24, the rotary shaft 13ais provided above each of the process cartridges 9Y, 9M, 9C and 9K, in parallel with the axis of the photosensitive drum 7, the opening and closing gear (large) 13bis fixed to an end of the rotary shaft 13aon that side, and an opening and closing gear (small) 13dis fixed to an end of the rotary shaft 13aon this side. And the rotary shaft 13ais rotatably supported with a bearing (not shown) with respect to the apparatus body 100.

[0185] Note that a case where the toner replenishing containers 12Y, 12M, 12C, 12K are inserted in a state where the process cartridges 9Y, 9M, 9C, 9K have already been inserted in the apparatus body 100, will be described.

[0186] When the toner replenishing containers 12Y, 12M, 12C, 12K are inserted in the apparatus body 100, the first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container of the toner replenishing container opening and closing member 14 is inserted into and engages with the first cartridge engagement portion (concave) 9hof the cartridge opening and closing member 9bthat is in the second position sealing the replenishing port position 9c(see FIG. 18). This engagement relationship is the same as in the case where the toner replenishing containers 12Y, 12M, 12C, 12K are first inserted in the apparatus body 100 and then the process cartridges 9Y, 9M, 9C, 9K are inserted therein. Further at this time, the gear 12nprovided on the rotary lever 12mof each of the toner replenishing containers 12Y, 12M, 12C, 12K is inserted into and engages with the opening and closing gear (small) 13don the apparatus body 100.

[0187] In this state, when the rotary lever 12mis rotated counterclockwise, the rotation drive of the gear 12nis transmitted to the cartridge opening and closing member 9bthrough the opening and closing gear (small) 13d, the rotary shaft 13a, and the opening and closing gear (large) 13b.

[0188] At this time, in the same manner as described in Embodiment 1, the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are integrally moved in the left direction (see FIG. 17). And when the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are moved from the respective second positions to the respective first positions, as shown in FIG. 17, the port 12f1 of the discharge port portion 12fof the toner replenishing containers 12Y, 12M, 12C, 12K and the replenishing port portion 9cof the process cartridges 9Y, 9M, 9C, 9K are communicated with each other through the opening 9fof the cartridge opening and closing member 9bso that the toner replenishing from the toner replenishing containers 12Y, 12M, 12C, 12K to the process cartridges 9Y, 9M, 9C, 9K is made.

[0189] Next, a toner replenishing structure of Embodiment 4 will be described with reference to FIG. 25, FIG. 26, and FIG. 27. Note that the same components as in Embodiment 1 are denoted by the same reference numerals. Thus, components different from those in Embodiment 1 will be described.

[0190] The point in this embodiment significantly different from Embodiment 1 is that, in contrast with Embodiment 1 where the rack 9gis formed on the cartridge opening and closing member 9band the rack 9gis moved by engagement with the opening and closing gear (large) 13bof the apparatus body 100. In this embodiment, each of opening and closing slide members 13e(see FIG. 26) of the apparatus body 100 engages with the cartridge opening and closing member 9band the cartridge opening and closing member 9bis moved by sliding of the opening and closing slide member 13e.

[0191] These arrangement configurations will be described in detail.

[0192] As shown in FIG. 26, the rotary shaft 13ais provided above each of the process cartridges 9Y, 9M, 9C and 9K, in parallel with the axis of the photosensitive drum 7, the opening and closing gear (large) 13bis fixed to an end of the rotary shaft 13aon that side, and the rotary lever 13cis fixed to an end of the rotary shaft 13aon this side. And the rotary shaft 13ais rotatably supported with a bearing (not shown) with respect to the apparatus body 100.

[0193] On that side of the apparatus body 100 are placed the frames 13d. On the frame 13dis placed the opening and closing slide member 13ewhich are horizontally moved in a direction perpendicular to the axial direction of the developing sleeve 10aof each of the process cartridges 9Y, 9M, 9C and 9K. The opening and closing slide member 13eis moved along a guide rib 13fformed on the frame 13d.

[0194] A rack 13gis formed on the upper surface of the opening and closing slide member 13eand engages with the opening and closing gear (large) 13b. Further, on this side of the opening and closing slide members 13eis formed a concave opening and closing groove 13h.

[0195] On the other hand, on the cartridge opening and closing member 9bof each of the process cartridges 9Y, 9M, 9C and 9K, as shown in FIG. 25 and FIG. 26, is provided a third cartridge engagement portion (convex) 9kwhich engages with the above-mentioned opening and closing groove 13h.

[0196] When the process cartridges 9Y, 9M, 9C, 9K are inserted into the apparatus body 100, as shown in FIG. 27, the third cartridge engagement portion (convex) 9kof the cartridge opening and closing member 9bthat is at the second position where the replenishing portion 9cis sealed or closed engages with the opening and closing groove 13hof the opening and closing slide member 13eso that the third cartridge engagement portion (convex) 9kand the opening and closing slide member 13ecan be integrally moved.

[0197] When the toner replenishing containers 12Y, 12M, 12C, 12K are inserted in the apparatus body 100, as mentioned above, the first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container of the toner replenishing container opening and closing member 14 is inserted into and engages with the cartridge engagement portion (concave) 9hof the cartridge opening and closing member 9b. This engagement relationship is the same as in the case where the toner replenishing containers 12Y, 12M, 12C, 12K are first inserted in the apparatus body 100 and then the process cartridges 9Y, 9M, 9C, 9K are inserted therein.

[0198] Then, when the rotary lever 13cis rotated clockwise, the opening and closing gear (large) 13bis rotated through the rotary shaft 13a, the opening and closing slide member 13eis moved in a direction perpendicular to the axial direction of the developing sleeve 10a, and at the same time the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are moved in the same direction (see FIG. 26). And when the cartridge opening and closing member 9band the toner replenishing container opening and closing member 14 are moved from the respective second positions to the respective first positions, the port 12f1 of the discharge port portion 12fof the toner replenishing containers 12Y, 12M, 12C, 12K and the replenishing port portion 9cof the process cartridges 9Y, 9M, 9C, 9K are communicated with each other through the opening 9fof the cartridge opening and closing member 9bso that the toner replenishing from the toner replenishing containers 12Y, 12M, 12C, 12K to the process cartridges 9Y, 9M, 9C, 9K is made.

[0199] Next, a toner replenishing structure of Embodiment 5 will be described with reference with FIG. 28 and FIG. 29. Note that the same components as in Embodiment 4 are denoted by the same reference numerals. Thus, components different from those in Embodiment 4 will be described.

[0200] The point in this embodiment significantly different from Embodiment 4 is that, in contrast with Embodiment 4 where the opening and closing slide members 13eare independently arranged at four positions, Embodiment 5 has a single opening and closing slide member (see FIG. 29), and by interlocking with the movement of the opening and closing slide members 13ethe cartridge opening and closing members 9bat four positions can be simultaneously opened or closed.

[0201] That is, when the process cartridges 9Y, 9M, 9C, 9K are inserted into the apparatus body 100, as shown in FIG. 29, the third cartridge engagement portion (convex) 9kof each cartridge opening and closing member 9bthat is at the second position where the replenishing port portion 9cof the process cartridge 9Y, 9M, 9C, 9K is sealed or closed engages with the opening and closing groove 13hof the opening and closing.slide member 13eso that the third cartridge engagement portions (convex) 9hand the opening and closing slide member 13ecan be integrally moved.

[0202] And when the toner replenishing containers 12Y, 12M, 12C, 12K are inserted in the apparatus body 100, as mentioned above, the first driving force receiving portion 14a(convex) for opening and closing the toner replenishing container of the toner replenishing container opening and closing member 14 is inserted into and engages with the first cartridge engagement portion (concave) 9hof each of the cartridge opening and closing members 9b. This engagement relationship is the same as in the case where the toner replenishing containers 12Y, 12M, 12C, 12K are first inserted in the apparatus body 100 and then the process cartridges 9Y, 9M, 9C, 9K are inserted therein.

[0203] Then, when the rotary lever 13cis rotated clockwise, the opening and closing gear (large) 13bis rotated through the rotary shaft 13a, the opening and closing slide member 13eis moved in a direction perpendicular to the axial direction of the developing sleeve 10a, and at the same time all the cartridge opening and closing members 9band all the toner replenishing container opening and closing members 14 are moved in the same direction (see FIG. 28). And when all the cartridge opening and closing members 9band all the toner replenishing container opening and closing members 14 are moved from the respective second positions to the respective first positions, the port 12f1 of the discharge port portion 12fof each of the toner replenishing containers 12Y, 12M, 12C, 12K and the replenishing port portion 9cof each of the process cartridges 9Y, 9M, 9C, 9hare communicated with each other through the opening 9fof each of the cartridge opening and closing members 9bso that the toner replenishing from the toner replenishing containers 12Y, 12M, 12C, 12K to the process cartridges 9Y, 9M, 9C, 9his made.

[0204] The toner replenishing containers shown Embodiments 1 to 5 are not limited to the replenishment to a process cartridge or a developing cartridge using the two-component development, but may also be used in the replenishiment to a process cartridge or a developing cartridge using monocomponent development. Further, powder contained in a toner replenishing container may include not only toner but also a mixture of toner and magnetic carrier, a so called developer.

[0205] Further, although a color toner electrophotographic image forming apparatus that uses two-component developer is described as an example in the above Embodiments, the present invention can be preferably applied to a color toner electrophotographic image forming apparatus using a monocomponent developer and a monochromatic electrophotographic image forming apparatus and the same effects can be also obtained.

[0206] Further, an electrophotographic photosensitive member (photoconductor) includes not only the photosensitive drum but also, for example, the following members. First, as the photosensitive member, photoconductor is used. The photoconductor includes, for example, amorphous silicon, amorphous selenium, zinc oxide, titanium oxide, organic photoconductor (OPC) and the like. Further, as a shape on which the photosensitive member is mounted, for example, a drum shape or a belt shape is used. In a drum-type photosensitive member, a photoconductor vapor-deposited or coated cylinder of aluminum alloy or the like can be used.

[0207] Incidentally the above-described process cartridge is defined as a member including, for example, an electrophotographic photosensitive member and at least one of process means. Therefore, the configuration of the process cartridge includes other than the ones in the Embodiments above, a cartridge integrally composed of an electrophotographic photosensitive member, developing means and charging means which is detachably mountable to the apparatus body, a cartridge integrally composed of an electrophotographic photosensitive member and developing means which is detachably mountable to the apparatus body, a cartridge integrally composed of an electrophotographic photosensitive member and cleaning means which is detachably mountable to the apparatus body, and further, a cartridge integrally combined an electrophotographic photosensitive member with two or more of the process means which is detachably mountable to the apparatus body.

[0208] That is, the above-described process cartridge is a cartridge integrally composed of the charging means, developing means or cleaning means and electrophotographic photosensitive member which is detachably mountable to the image forming apparatus body. The process cartridge is a cartridge integrally composed of at least one of the charging means, developing means and the cleaning means, and the electrophotographic photosensitive member which is detachably mountable to the image forming apparatus body, or a cartridge integrally composed of at least the developing means and electrophotographic photosensitive member which is detachably mountable to the image forming apparatus body. And a user himself can attach and detach this process cartridge from the apparatus body. Accordingly a user can perform maintenance by himself.

[0209] Further, in the above-described Embodiments, as an electrophotographic image informing apparatus a color laser beam printer is described. However, the present invention is not limited to this. Thus the present invention can be applied to another electrophotographic image forming apparatus such as an electrophotographic copier, a facsimile device or a word processor.

[0210] As described above, in an electrophotographic image forming apparatus of the present invention, a developer replenishing container containing a developer, and a cartridge connectable to the developer replenishing container can be independently mounted to the electrophotographic image forming apparatus body. And in a state where the developer replenishing container and the cartridge are mounted to the electrophotographic image forming apparatus body, the developer can be replenished from the developer replenishing container to the cartridge.

[0211] While the present invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.