Method and Device for Supplying a Fresh Cotton Bale in a Bale Plucking Machine

The present invention relates to a method and device for supplying a fresh cotton bale to a bale plucking machine wherein fiber tufts are plucked from the botton of a pressed fiber bale.

In the coventional bale plucking operation, fiber tufts are continuously plucked from a pressed cotton bale by a plucking roller when the pressed cotton bale is reciprocally displaced over the plucking roller by means of a pair of conveyer belts. The mass of the cotton bale is gradually reduced by the above-mentioned plucking operation and, finally, exhausted. Thereafter, a fresh cotton bale is supplied to one of the above-mentioned conveyer belt so as to continue the bale plucking operation.

In the above-mentioned bale plucking operation, the rate of plucking the fiber tufts from the pressed fiber bale and the size of the plucked fiber tufts are influenced by the pressing force which urges the fiber bale toward the plucking roller, after the mass of the fiber bale is reduced to a certain limit by the plucking operation. Since the above-mentioned pressing force depends upon the weight of the cotton bale displacing over the plucking roller and, further, the weight of the fiber bale decreases during the plucking operation, the plucking rate and size of the plucked fiber tufts vary with the passage of time in the plucking operation. Therefore, such variations of plucking rate, and of size of plucked fiber tufts, have an undesirable influence upon the successive process steps such as irregular opening and cleaning of fiber tufts. For example, in the case of utilizing a plurality of bale plucking machines for carrying out an opening and mixing operation of fiber tufts plucked from different cotton bales, the mixing ratio of the fiber tufts is changed according to the variation of the plucking rate and size of the plucked fiber tufts.

To solve the above-mentioned problem, a method (or device) for compensating for the above-mentioned decrease of the weight of the cotton bale during the plucking operation has been utilized. However, such compensation device makes the structure of the plucking machine more complex so that the installation cost of the plucking machine is increased.

Further, in the conventional plucking machine, the supply of a fresh fiber bale to the bale plucker is carried out manually. Therefore, the plucking operation is stopped at the time of supplying a fresh fiber bale. Thus, the working efficiency of the plucking machine is reduced.

The principal object of the present invention is to solve the above-mentioned problems of conventional bale plucking machines, by providing a unique method and device for supplying a fresh fiber bale to a bale plucking machine.

According to the present invention, when the mass of the pressed fiber bale on the conveyer means is reduced to a predetermined limit, the reciprocal carrying motion of the conveyer means is temporarily stopped so as to position the fiber bale being processed at a predetermined position on one of the conveyer means. Next a fresh fiber bale is fed to the above-mentioned conveyer means in such a condition that the fresh fiber bale is superimposed upon the fiber bale being processed. Then, the reciprocal displacing motion of the conveyer means is restarted so as to displace the superimposed fiber bales to a working position of the plucking roller. The above-mentioned motion is repeated each time the mass of fiber bale on the conveyer means is reduced to a predetermined limit.

To carry out the above-mentioned operation for supplying a fresh fiber bale to the conveyer means, an additional conveyer means is disposed at a position above and adjacent to a part of one of the conveyer means, and a detector for detecting the condition of mass of the fiber bale, which is being processed, is disposed at a position adjacent to a displacing passage of the fiber bale on the conveyer means. When the above-mentioned detector detects that the mass of the fiber bale being processed has reached a predetermined condition, the detector issues a signal to stop the motion of the conveyer means and then the additional conveyer means is driven so as to supply a fresh fiber bale onto one of the conveyer means in such a condition that the fresh fiber bale is positioned upon the fiber bale being processed in superimposed condition.

Consequently, with the present invention the motion of supplying a fresh fiber bale to the conveyer means can be carried out automatically without any troublesome manual operations. Further, if a plurality of plucking machines are utilized to carry out the mixing operation of several different raw materials, the mixing ratio can be maintained uiform during the plucking operation since the plucking rate of the fiber bale in each plucking machine can be maintained uiform during the plucking operation.

FIG. 1 is a schematic side view of a bale plucking machine provided with the apparatus according to the present invention;

FIG. 2 is a schematic plan view of the bale plucking machine shown in FIG. 1;

FIG. 3 is a side view, partly in section, of a stopper utilized for the bale plucking machine shown in FIG. 1;

FIG. 4 is a sectional view of a part of the stopper taken along the line IV--IV, in FIG. 3;

FIG. 5 is a schematic perspective view of the stopper shown in FIG. 3;

FIG. 6 is a side view, partly in section of a limit switch utilized for the bale plucking machine shown in FIG. 1;

FIG. 7 is a diagram of an electric circuit of the magnetic relays applied to the bale plucking machine shown in FIG. 1;

FIG. 8 is a block diagram of a control circuit utilized for the bale plucking machine shown in FIG. 1.

In the bale plucking machine shown in FIGS. 1 and 2, a pair of conveyer means 1 and 2 are disposed in alignment with an intervening space therebetween, and a plucking roller 6 is disposed in the above-mentioned intervening space in such a condition that the circular profile of the plucking roller is projected into the supporting level of the fiber bale which is identical to a horizontal plane passing through the top surfaces of the conveyer means 1 and 2. The conveyer blet means 1 comprises guide rollers 1a, 1b and 1c and an endless apron 1d supported by these rollers 1a, 1b and 1c. The guide roller 1c works as a drive roller. A roller 1f is disposed at a position below the guide roller 1b in such a condition that the roller 1f rotatably contacts the endless apron 1d. The guide roller 1a is positioned at a lower level than the disposition of the guide rollers 1b and 1c so that the endless apron 1d is partly inclined as shown in FIG. 1. The conveyer means 2 comprises guide rollers 2a and 2b and an endless apron 2c supported by these rollers 2a and 2b. The guide roller 2a works as a drive roller. An additional horizontal conveyer means 9 is disposed above the inclined portion of the endless apron 1d in such a way that the distance between the forward end of the conveyer means 9 and the inclined portion of the endless apron 1d is larger than l (FIG. 1), where l represents the predetermined thickness of a cotton bale on top of which a fresh cotton bale should be supplied. Further, it is required to position the conveyer means 9 in such a condition that the upper surface of the conveyer means 9 substantially coincides with a horizontal plane Y--Y which is positioned above a horizontal plane X--X defined by the upper horizontal surfaces of the endless apron 1d and 2c at a distance l(cos .theta.).sup.2 where .theta. represents the inclined angle of the left-hand portion of endless belt 1d as viewed in FIG. 1. The additional conveyer belt means 9 comprises a pair of guide rollers 9a and 9b, and an endless apron 9c supported by the guide rollers 9a and 9b as shown in FIG. 1. The guide roller 9b is a drive roller. An additional roller 12 is rotatably disposed in a space between the endless apron 9c and the inclined portion of the endless apron 1d in such a condition that the roller 12 is positioned at the same level as the endless apron 9c.

A reversible motor 3 is disposed below the conveyer means 2 and a roller 2a is driven by the motor 3 by way of a power transmission mechanism comprising a plulley 3a rigidly mounted on a shaft of the motor 3 and a pulley 2d rigidly mounted on an end portion of a shaft of the roller 2a and an endless belt 4 mounted on the pulleys 2d and 3a. A motor 7 is disposed below the plucking roller 6 and the roller 6 is driven by the motor 7 by way of a power transmission mechanism comprising a pulley 7a secured to a shaft of the motor 7 and a pulley 6a secured to a shaft of the plucking roller 6 and an endless belt 8 mounted on the pulleys 6a and 7a. Another pulley 2e is secured on another end of the shaft of the roller 2a, while a pulley 1e is secured to a shaft of the roller 1c in a condition facing the pulley 2e. The driving power of the pulley 2e is transmitted to the pulley 1e by an endless belt 5. Consequently, the endless aprons 1d and 2c are synchronously driven and stopped. A motor 10 is disposed at a position below the additional conveyer means 9, and the roller 9b is driven by the motor 10 by way of a power transmission mechanism comprising a pulley 10a secured on a shaft of the motor 10 and a pulley 9d secured on a shaft of the roller 9b and an endless belt 11 mounted on the pulleys 10a and 9d.

A pair of detectors 14 and 15 (shown diagrammatically in FIGS. 1 and 2) are mounted above the conveyer means 1 and 2, respectively, as shown in FIGS. 1 and 2. That is, the detector 14 is mounted at a position to and above an end portion of the endless apron 2c. The detector 14 comprises a light projector 14a and a photocell 14b which is capable of receiving light issued from the light projector 14a. These elements 14a and 14b of the detector 14 are shown diagrammatically in FIG. 2 and are respectively disposed at facing positions outside the endless apron 2c as shown in FIG. 2. The detector 15 has a structure similar to the detector 14. That is, the detector 15 comprises a light projector 15a and a photocell 15b which is capable of receiving light issued from the light projector 15a. The light projector 15a and the photocell 15b are shown diagrammatically and are disposed in facing condition at particular positions adjacently above the roller 1b in such a way that the distance between a light beam issued from the light projector 15a and the horizontal plane X--X is the above-mentioned predetermined value l. The positions of the light beam issued from the light projector 14a and the light beam issued from the light projector 15a are selected so as to coincide with terminals of the reciprocal motion of a fiber bale which is caused by the motion of the conveyer means 1 and 2. A stopper 16 is adjustably mounted on the inclined portion of the endless apron 1d at a position adjacent to the roller 1a so as to temporarily position a fiber bale being processed on the inclined portion of the endless apron 1d when a fresh fiber bale is supplied thereon, and a limit switch is mounted to a bracket of the stopper 16 in such a condition that when the fiber bale being processed contacts the stopper 16, the limit switches 17 (FIGS. 1 and 2) are actuated. A detailed explanation of the stopper 16 and the limit switches 17 (which are shown diagrammatically in FIGS. 1 and 2) will be presented later.

Another detector 18 is disposed at a position above the inclined portion of the endless apron 1d as shown in FIG. 1. The detector 18 comprises a light, projector 18a and a photocell 18b which is capable of receiving a light beam issued from the light projector 18a. These elements 18a and 18b of the light projector 18 are positioned in facing condition at particular positions above the inclined portion of the endless apron 1d which is adjacent to the roller 1b where a fresh fiber bale is first placed in contact with a fiber bale being processed, which is temporarily supported by the inclined portion of the endless apron 1d. Another limit switch 19 is disposed at a position adjacent to the roller 12. This limit switch 19 issues a signal when a tail end of the fresh cotton bale passes thereover, so as to stop the running of the motor 10. The detailed structure and function of the limit switch 19 will be explained later.

Referring to FIGS. 3, 4 and 5, the stopper 16 comprises an upright wall portion 16a and a pair of legs 16b slidably mounted on side frames 20 of the conveyer means 1. Each leg 16b is provided with a pair of slots 16c and 16d wherein a guide stud 21, which is secured to the side frame 20, passes respectively. A fastener 22 is secured to a top end portion of each stud 21 so as to hold leg 16b in a condition that each leg 16b is capable of sliding along the side frame 20. A pair of helical springs 23 are disposed in each slot 16c (or 16d) in a condition that the stud 21 is sandwiched by the springs 23. These springs 23 work as shock absorbers when a fiber bale being processed contacts the wall portion 16a. An axxiliary feeler 17b is slidably inserted in an aperture formed in the wall portion 16a and the auxiliary feeler 17b is provided with an expanded head 17c which is capable of projecting from a space 16e of the wall portion 16a toward an outside direction. To prevent escape of the auxiliary feeler 17b from the aperture of the wall portion 16a, a flexible sheet 16f is mounted on the wall portion 16a as shown in FIG. 3. An expansion spring 17d is inserted in the space 16e so as to always urge the head portion 17c toward the flexible sheet 16f. The limit switch 17 is secured to the wall portion 16a at the position where the free end of the auxiliary feeler 17b is capable of actuating a feeler 17a of the limit switch 17 when a processing fiber bale pushes the flexible sheet 16f. As mentioned above, the stopper 16 is capable of fixing the working position thereof by changing the securing position of the studs 21 on the side frames 20. And when the feeler 17b is pushed by the processing fiber bale, the limit switch 17 is actuated.

The structure and function of the limit switch 19 is hereinafter explained. Referring to FIG. 6, a transversal bracket 26 is secured to a pair of side frames 25 of the conveyer means 9. At the end of the side frames 25, the roller 12 is rotatably mounted. The limit switch 19 is secured to the transversal bracket 26 at its central portion. A small bracket 27 is secured to the transversal bracket 26 at a position corresponding to the disposition of the limit switch 19. An auxiliary feeler 29 is turnably supported by the small bracket 27 by way of a pin 28. The auxiliary feeler 29 is provided with a horizontally projected protion 29a formed at the top end thereof and a small horizontally projected portion 29c, which is extended to a position adjacently above the limit switch 19 in such a condition that the portion 29c always contacts a feeler 19a of the limit switch 19 during the normal plucking operation. The auxiliary feeler 29 is also provided with a lowered extended portion 29b. The portion 29b is provided with an aperture 29d. A stud 30 is turnably mounted on the bracket 26 by a pin 31 as shown in FIG. 6 and the top end portion of the stud 30 is inserted in the aperture 29d and a fastening member 32 is secured to the top end of the stud 30. An expansion spring 33 is mounted on the stud 30 at position between the extended portion 29b and the bracket 26 so that the auxiliary feeler 29 is always urged to turn clockwise about the pin 28. However, the position of the feeler 29 is fixed by the fastening member 32. In the above-mentioned condition, the small projected portion 29c pushes the feeler 19a of the limit switch 19 which opens its electric circuit in this condition and closes its electric circuit when the projected portion 29c is removed from the feeler 19a. The auxiliary feeler 29 is turned counterclockwise when a fresh cotton bale is supplied to the conveyer belt means 1 and front and tail ends of the fresh cotton bale contact the horizontal projection 29a.

Means for controlling the motions of the conveyer belt means 1, 2 and 9 is hereinafter explained with reference to FIGS. 7 and 8. The reversible motor 3 is connected to an electric source by way of an on-off relay 35 and a conventional reversible magnetic relay 36 which are arranged in a series. The photocells 14b and 15b are connected to the magnetic relay 36 in such a way that the photocell 14b actuates a solenoid (not shown) so as to close contacts m1, m2 and m3 (FIG. 7) while the photocell 15b actuates a solenoid (not shown) so as to close contacts n1, n2 and n3. Consequently, the polarity of input power into the motor 3 is changed alternately by the signals issued from the photocells 14b, 15b of the respective detectors 14 and 15. These detectors 14 and 15 are provided with means for issuing signals when light beams projected from the respective light projectors 14a, 15a, are shut out by the fiber bale being processed P' so that the photocells 14b, 15b do not receive the light from the light projectors 14a, 15a, respectively. The limit switch 17 is connected to the on-off relay 35 so as to open the relay 35 when the limit switch 17 is actuated. Therefore, a fiber bale is capable of reciprocally displacing along the horizontal plane X--X between the light beams issued from the light projectors 14a and 15a of the respective detectors 14 and 15.

The control circuit utilized for the bale plucker is hereinafter explained in detail. For the sake of easy understanding of the function of the device according to the present invention, the operation of the device of the present invention is also explained in the following paragraph.

Referring to FIGS. 1, 2 and 8, in the present invention, the detector 15 is positioned at a particular disposition above the horizontal plane XX or the conveyer means 1 and 2. That is, the distance between the ligth beam issued from the light projector 15a of the detector 15 and the horizontal plane XX is selected to be l, which corresponds to the mass of a fiber bale being processed on which a fresh fiber bale should be supplied. Therefore, when the height of the fiber bale being processed becomes lower than the light beam projected from the light projector 15a, the photocell 15b does not issue a signal, the fiber bale being processed is displaced to the inclined portion of the endless belt 1d. When the fiber bale being processed contacts the stopper 16, the limit switch 17 issues a signal to open the on-off relay 35 so that the motor 3 is stopped. In this condition, the fiber bale being processed is temporarily positioned on the inclinded portion of the endless belt 1d. The limit switch 17 also issues a signal to close an on-off relay 37 which connects or disconnects the motor 10 with the electric source so that the on-off relay 37 is closed. Consequently, the motor 10 is driven and a fresh fiber bale stored on the Conveyer means 9 is carried to the conveyer means 1. When the light beam projected from the light projector 18a (FIG. 2) is intercepted by the fresh fiber bale F so that the photocell 18b does not receive the light from the projector 18a, the detector 18 issues a signal to close the on-off relay 25 in the same manner as the detector 15, so that the conveyer means 1 is driven. Accordingly, the fresh fiber bale F and the fiber bale being processed P' are carried toward the conveyer means 2 in superposed condition. The limit switch 17 also issues a signal when a fiber bale P' contacts the stopper 17, and this signal is transmitted to a timer switch 38, which connects the limit switch 19 with the electric source, so as to disconnect the limit switch 19 from the electric source for a fixed time which is sufficient to prevent the actuation of the limit switch 19 when a forward tail end portion of the fresh fiber bale F passes over the projected portion 29a (see FIG. 6). Therefore, even if the forward tail end portion of the fresh fiber bale F pushes the projected portion 29a of the auxiliary feeler 29, the limit switch 19 does not actuate. However, when a tail end portion of the fresh fiber bale F pushes the projected portion 29a, the limit switch 19 is actuated so that the on-off relay 37 is opened. Accordingly the motor 10 is stopped. The motor 7 for driving the plucking roller 6 is connected to the electric source by way of an on-off relay 39. The on-off relays 35 and 39 are initially closed by a push button 40 when the plucking operation is commenced.

As mentioned above, the plucking operation is always carried out on a fiber bale being processed which has a mass which is heavier than a predetermined weight so as to maintain a uniform plucking operation.

According to our experience, it is perferable to utilize an auxiliary conveyer belt means 9 provided with a sufficient length for reserving a plurality of fresh fiber bales thereon so as to always reserve a fresh fiber bale F at a forward position adjacent to the roller 9a. In this case, a plurality of fresh fiber bales may be supplied on the endless apron 9c at one time so that the manual cost for supplying the fresh fiber bales on the endless apron 9c can be effectively reduced.

In the above-mentioned embodiment, the endless aprons 1d, 2c and 9c are utilized for the respective conveyer means 1, 2 and 9. Instead of utilizing these endless aprons 1d, 2c and 9c, roller conveyer means comprising a plurality of horizontal rollers arranged in parallel and driven by a conventional power transmission means such as a belt or chain drive mechanism can be utilized.