JP3581375B2 - Collection method and image forming apparatus - Google Patents

Description

[0001]
[Industrial applications]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine of an electrophotographic type, an electrostatic recording type or the like, a printer, etc. Although it is not a thing, for example, it has a plurality of image forming means, forms a plurality of visible images of different colors on an image carrier by these image forming means, and carries these visible images by a recording material carrying means, The present invention is suitable for a color image forming apparatus such as a color copying machine or a color printer which sequentially transfers images onto the same recording material.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, an image forming apparatus that includes a plurality of image forming units, forms visible images (toner images) of different colors in each image forming unit, and sequentially superimposes and transfers these toner images onto the same recording material, a so-called image forming apparatus Various color image forming apparatuses have been proposed, and among them, an electrophotographic color image forming apparatus is frequently used. In such an electrophotographic color image forming apparatus, a plurality of image forming units, generally four image forming units, are arranged side by side, and a dedicated photosensitive drum is used as an image carrier of these image forming units. A yellow, magenta, cyan, and black visible image, that is, a toner image, is separately formed on a drum, and each color is sequentially formed on a recording material carried and conveyed by a recording material carrying unit including, for example, a dielectric belt. The toner images are superimposed and transferred, and the multiple toner images on the recording material are collectively heated and fixed by a fixing device to obtain a required full-color image or multi-color image.
[0003]
An example of such an electrophotographic color image forming apparatus will be briefly described with reference to FIG. The color image forming apparatus can form, for example, visible images (toner images) of yellow, magenta, cyan, and black in a main body of the apparatus, and includes first to fourth four image forming units Pa, Pb, and Pc. And Pd are linearly arranged, and each of the image forming units Pa to Pd includes a dedicated photosensitive drum 1a, 1b, 1c and 1d as an image carrier. Each of the photoconductor drums 1a to 1d is driven to rotate in the direction of the arrow shown in the figure. 3b, 3c, 3d, developing means 4a, 4b, 4c, 4d, cleaning means 5a, 5b, 5c, 5d and the like are provided.
[0004]
Below the photosensitive drums 1a to 1d of the image forming units Pa to Pd, a recording material carrying means, in this example, a recording material carrying belt 8 that moves endlessly is stretched between a plurality of rollers in a known manner. Transfer charging means 6a, 6b, 6c, and 6d are provided therein. Further, a sheet feeding unit is disposed on the right side of the recording material carrying belt 8 in the drawing, and a fixing unit 7 is disposed on the opposite side, that is, on the left side in the drawing. Further, a pair of registration rollers 13 for feeding the recording material P at a time is arranged between the paper supply unit and the recording material carrying belt 8. The belt 8 is fed and held on the recording material carrying belt 8 via the belt 13, and is sequentially conveyed to the transfer areas of the image forming units Pa to Pd as the belt 8 moves in the direction indicated by the arrow.
[0005]
In the above-described configuration, the recording material P sent out from the paper feeding unit temporarily stops when its tip is slightly sandwiched by the registration rollers 13, and is synchronized with the image forming process of the first image forming unit Pa. The sheet is fed out and fed onto the recording material carrying belt 8. In the first image forming unit Pa, the image information of the yellow component color in the original image is scanned by the laser beam or the like on the photosensitive drum 1a uniformly charged by the charging unit 2a, and the electrostatic latent of the yellow component color is scanned. An image is formed. The electrostatic latent image becomes a yellow visible image by the yellow toner adhered by the developing means 3a.
[0006]
On the other hand, the recording material P is conveyed while being carried on a recording material carrying belt 8, and is transferred onto the photosensitive drum 1a by the operation of the transfer charging means 6a in the lower transfer area of the photosensitive drum 1a of the first image forming unit Pa. Is transferred onto the recording material P. While the yellow toner image is transferred onto the recording material P in this manner, an electrostatic latent image of a magenta component color is formed in the second image forming portion Pb, and this electrostatic latent image is developed by the developing means 3b. When the recording material P is conveyed to a transfer area below the photosensitive drum 1b of the second image forming unit Pb, the magenta toner image moves to the transfer area, and is transferred by the transfer charging unit 6b. The image is transferred in a state of being superimposed on the yellow toner image on the recording material P.
[0007]
Hereinafter, cyan and black toner images are sequentially formed in the third and fourth image forming units Pc and Pd in the same manner as in the first and second image forming units Pa and Pb. These toner images are sequentially multiplex-transferred onto the recording material P conveyed by the belt 8.
[0008]
When the image forming process is completed, the recording material P is separated from the recording material carrying belt 8 and sent to the fixing unit 7, where it is collectively fixed to obtain a desired full-color image. The cleaning unit 5a to 5d removes residual toner from the photosensitive drums 1a to 1d of the image forming units Pa to Pd after the transfer is completed, and prepares for the subsequent latent image formation.
[0009]
Note that the recording material carrying belt 8 is supported by a recording material carrying belt support 10, and can be pulled out to the front of the apparatus main body during maintenance or jam clearance. The recording material carrying belt support 10 is slidably supported by the apparatus main body by rail members 11 and 12 provided on both sides thereof.
[0010]
By the way, such a color image forming apparatus is widely known as a developing method which uses a two-component developer composed of a toner which is a developer and a carrier which gives a charge to the toner. In this two-component developing method, the carrier used deteriorates as the image formation is repeated, so that the developer needs to be replaced at predetermined intervals.
[0011]
Therefore, the developing device using the two-component developing method must have a configuration capable of collecting the deteriorated developer from the developing device.
[0012]
FIG. 13 is a schematic sectional view showing an example of a developing device used in the image forming apparatus shown in FIG. The developing device includes a developing container 41 for storing the developer D, a developing sleeve 42 as a developer carrying member for carrying and transporting the developer D to a developing unit facing the photosensitive drum 1, and a developing device in the developing container 41. A first screw 43 and a second screw 44 as a stirring / conveying member for stirring and mixing the developer D and supplying the developer D to the developing sleeve 42 are provided.
[0013]
The developer D is circulated in the developing device when the developing sleeve 42 and the two screws 43 and 44 rotate. When the magnetic pole arrangement of the fixed magnet roller 46 in the developing sleeve 42 has a five-pole configuration as illustrated, the developer D is pumped to the N2 pole of the developing sleeve 42 by the first screw 43. Then, the developer is conveyed to a developing pole (S1 pole) via a doctor blade 45 that regulates a passing amount of the developer, and thereafter, the developer is carried on the developing sleeve 42 by a repulsive magnetic field formed by the N2 pole and the N3 pole. Instead, it falls by gravity and is taken into the first screw 43.
[0014]
FIG. 14 shows the developing sleeve 42 and the two screws 43 and 44 in an unfolded state. The circulation path of the developer by the screws 43 and 44 is indicated by arrows. As illustrated, the two screws 43 and 44 transport the developer in the opposite direction in the longitudinal direction, and transfer the developer between the screws at both ends of the developing container 41.
[0015]
As a method of collecting the developer in such a developing device, conventionally, a collecting hole R that can be closed by a cap or a shutter or the like at the time of normal image formation is provided in a portion of a developing container below a developer circulation path. The developer is discharged from the collecting hole R to the outside of the developing device by gravity while rotating the developing sleeve 42 and the screws 43 and 44.
[0016]
[Problems to be solved by the invention]
However, in the above-described conventional example, it is necessary to open a cap or a shutter that closes the developer collecting hole R, or to set a collecting container for collecting the developer below the collecting hole R of the developing device. First, the recording material carrying belt 8 and its support 10 must be pulled out to the front of the apparatus, and a hand must be inserted under the developing device to perform the operation. However, there is a possibility that the developer may be spilled from the collection container by mistake, and there is a disadvantage that the workability is extremely poor.
[0017]
In order to avoid this, there is a method of taking out the developing device and collecting the developer at another place in the main body, but in this case, it is disadvantageous in terms of cost and also involves the work of attaching and detaching the developing device. Therefore, there is a problem that maintenance is deteriorated. In particular, this problem is significant because a multicolor image forming apparatus has a plurality of developing devices.
[0018]
Accordingly, an object of the present invention is to provide a developer collecting method and an image forming apparatus which are excellent in operability in collecting deteriorated developer.
[0019]
[Means for Solving the Problems]
The above object is achieved by an image forming apparatus according to the present invention. In summary, according to the first aspect of the present invention, a latent image formed on an image carrier is provided at the bottom of a developing device for developing with a developer.WasIn the recovery method of recovering the developer from the recovery hole,
An attaching step of attaching a collection container for collecting the developer in a state where the drawer unit that can be pulled out with respect to the image forming apparatus main body is pulled out, and mounting the drawer unit such that the collection container is located below the collection hole. A collection step of: moving the developer; and collecting the developer from the collection hole to the collection container.Is done.
[0020]
According to a second aspect of the present invention, an image carrier and a developing device for developing a latent image formed on the image carrier with a developerAnd the imageA drawer unit that can be pulled out from the forming apparatus main body, and an image forming apparatus that forms an image on a recording material,
The drawer unit includes an attachment portion to which a collection container for collecting the developer when the drawer is in the pulled-out state is attached,
Collect developerForWhen moving the drawer unit to which the collection container is attached, the collection container is provided at the bottom of the developing device.WasAn image forming apparatus is provided, comprising a positioning means for positioning the position of the collection container so as to be located below the collection hole. According to one embodiment, the developer includes a toner and a carrier, and the carrier is collected from the collection hole to the collection container.it can.
[0021]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following embodiments, a case where the present invention is applied to an electrophotographic color image forming apparatus will be described. However, the present invention is not limited to the embodiments and is not limited to electrophotographic systems and electrostatic recording systems. It is equally applicable to forming equipment.
[0022]
First, a first embodiment of the present invention will be described with reference to FIGS.
[0023]
FIGS. 1 to 3 are schematic cross-sectional views showing a main part of the first embodiment of the present invention. The cross section of the electrophotographic color image forming apparatus shown in FIG. FIG. 4 is a schematic cross-sectional view when viewed from above. FIG. 1 shows a state when the deteriorated developer is being collected, and FIG. 2 shows a state during normal image formation. Components and members corresponding to those in FIGS. 13 and 14 are denoted by the same reference numerals, and description thereof will be omitted unless necessary.
[0024]
Next, a procedure for collecting the deteriorated developer in the image forming apparatus of the present embodiment will be described. Since the developing devices 4a to 4d have substantially the same configuration, only a case where the deteriorated developer is collected from one developing device will be described as a representative example.
[0025]
In FIG. 2, first, the screw 110 holding the lever 103 to the developing device is removed. As a method of stopping the lever 103, a locking means such as a click may be considered. However, since the damage is large when the lever 103 is accidentally pulled (the developer spills on the recording material carrying belt 8), safety is taken into consideration. It is screwed. Next, the recording material carrying belt 8 is separated from the photosensitive drum, and is pulled out to the front (right side in the drawing) of the apparatus main body together with the recording material carrying belt support 10 as a draw-out unit. Then, as shown in FIG. 3, the collection container 104 is set on the recording material carrying belt support 10, and the recording material carrying belt support 10 is pushed into the rear of the apparatus main body. As a result, as shown in FIG.One component of the device bodyThe collection container 104 is positioned below the collection hole R at the bottom of the developing device by abutting the centering plate 99. In this state, by pulling the lever 103 forward, the shutter 101 as an opening / closing member opens. Then, the developing sleeve 42 and the first and second screws 43 and 44 (the first screw 43 is not visible in FIGS. 1 to 3) are rotated to collect the developer D into the collection container 104.
[0026]
When the discharge of the developer is completed, the shutter 101 is closed by pushing the lever 103. Then, the recording material carrying belt support 10 is pulled out toward the user, and the collection container 104 containing the deteriorated developer is removed upward. Next, the recording material carrying belt 8 is returned together with the support 10 into the apparatus main body, and the lever 103 is fixed with the screw 110.
[0027]
Thus, the developer collection operation is completed. The new developer may be supplied from the supply port Q provided in the developing container 41 while the developing sleeve 42 and the first and second screws 43 and 44 in the developing device are driven.
[0028]
As described above, in the present embodiment, the collection container 104 is attached to the recording material carrying belt support 10 pulled out to the front of the apparatus main body, and then pushed backward and stopped at a predetermined position to collect the developer. Since it is not necessary to open and close the shutter or the cap below the developing device after inserting the hand into the apparatus main body and placing the collection container 104 at a predetermined position, the developing device Since there is no need to perform a troublesome operation (operation) such as detaching and moving to another collection place in the main body, the developer can be easily collected without fear of spilling the developer. Therefore, workability is significantly improved. Further, it is advantageous in terms of cost and maintainability.
[0029]
In the above embodiment, the recovery container 104 is positioned below the recovery hole R at the bottom of the developing device by the projection M of the recovery container 104 abutting on the centering plate 99. However, the positioning method of the recovery container 104 is not limited to this. It is not done. For example, as shown in FIG. 4, a protrusion N made of a “L” shaped elastic member that protrudes upward in the vicinity of the free end is attached to the collection container 104, or formed integrally with the collection container 104. A hole A is formed in the centering plate 99 so as to engage with the protrusion of the projection N of the collection container 104, and when the recording material carrying belt support 10 is pushed into the rear of the apparatus main body, as shown in FIG. The projection of the projection N of the container 104 may be engaged with the hole A of the centering plate 99 to position the collection container 104 below the collection hole R at the bottom of the developing device. Of course, various other known positioning methods can be used.
[0030]
In the above embodiment, the collection container 104 is attached to the recording material carrying belt support 10, but the present invention is not limited to this. For example, a roller that stretches the recording material carrying belt, a support structure, The collection container may be attached to a recording material carrying means other than the recording material carrying belt such as a drive mechanism.
[0031]
Next, a second embodiment of the present invention will be described with reference to FIGS.
[0032]
FIGS. 5 and 6 are schematic cross-sectional views showing the main parts of a second embodiment of the present invention. The cross section of the electrophotographic color image forming apparatus shown in FIG. FIG. 4 is a schematic cross-sectional view when viewed from above. FIG. 5 shows a state when the deteriorated developer is being collected, and FIG. 6 shows a state during normal image formation. Components and members corresponding to those in FIGS. 13 and 14 are denoted by the same reference numerals, and description thereof will be omitted unless necessary.
[0033]
Next, a procedure for collecting the deteriorated developer in the image forming apparatus of the present embodiment will be described. Since the developing devices 4a to 4d have substantially the same configuration, only a case where the deteriorated developer is collected from one developing device will be described as a representative example.
[0034]
In FIG. 6, first, the screw 110 holding the lever 103 (operation means) to the developing device is removed. As described above, a locking means such as a click may be considered as a method for stopping the lever 103. However, since the damage when the lever 103 is pulled by mistake is large (the developer spills on the recording material carrying belt 8), In this embodiment, screws are used in consideration of safety. Next, the recording material carrying belt 8 is separated from the photosensitive drum, and is pulled out together with the recording material carrying belt support 10 to the front (right side in the figure) of the apparatus main body. Then, as shown in FIG. 5, the collecting container 104 is placed below the collecting hole R provided on the bottom surface of the developing container 41. (It goes without saying that the method of attaching the collection container shown in the first embodiment described above is more preferable.) In this state, when the lever 103 is pulled forward (in the direction of arrow I), the shutter 101 is moved by the arrow J due to its own weight. And the collection hole R is opened. Then, the developing sleeve 42 and the first and second screws 43 and 44 (the first screw 43 is not visible in FIGS. 5 and 6) in the developing device are rotationally driven in the same manner as in normal image formation. As a result, the developer D is discharged from the collection hole R and collected in the collection container 104.
[0035]
When the discharge of the developer is completed, the shutter 101 is rotated in the direction of the arrow L by pushing the lever 103 backward (in the direction of the arrow K), and the collection hole R is closed. Here, the seal member 102 is for preventing the developer D from leaking from the gap between the developing container 41 and the shutter 101 in the collecting hole. 5 and 6, the seal member 102 is provided on the shutter side, but may be provided on the developing container side. When a material such as polyurethane foam, which is generally widely used, is used as the seal member, it is necessary to consider damage to the seal member. In this embodiment, since the operation of the shutter 101 is not a sliding operation but a rotating operation, the seal member 102 does not rub against other members, so that there is an advantage that damage is less likely to occur.
[0036]
Thereafter, the collection container 104 is taken out of the apparatus main body, the recording material carrying belt 8 is returned together with the support 10 in the apparatus main body, and the lever 103 is fixed with the screw 110, thereby completing the developer collection operation.
[0037]
The new developer may be supplied from the supply port Q provided in the developing container 41 while the developing sleeve 42 and the first and second screws 43 and 44 in the developing device are driven.
[0038]
7 to 9 are enlarged detailed views for supplementarily explaining the shapes and mechanisms of the shutter 101 and the lever 103. 7 and 8 are views of the developing device as viewed from below. FIG. 7 shows a state in which the shutter 101 is closed, and FIG. 8 shows a state in which the shutter 101 is open. FIG. 9 is a sectional view of FIG. 5 taken along line 9-9 and viewed in the direction of the arrow. As shown in the figure, the developing container 41 is provided with a plurality of protrusion members 411 to 415. Of these protrusion members, the protrusion members 411 and 412 hold the shutter 101 and support the rotation of the shutter 101. It is what becomes. The projection members 413 and 414 hold the lever 103 and also serve as guide rails for the sliding movement of the lever 103. The projection member 415 is a stopper of the lever 103 when the shutter is opened, and abuts on the lever 103 at a position V in FIG. When the shutter is closed, the projection member 414 serves as a stopper, and abuts on the lever 103 at the position U in FIG.
[0039]
When the lever 103 is attached to and detached from the developing device, the projecting member 415 blocks the path, so that the projecting member 415 can be attached to and detached from the developing container 41 in advance, or can be retracted from the path of the lever 103. Keep it. As an example of the retracting method, the developing container 41 is divided into two parts between the projecting members 415 and the projecting members 413 and 414, and the developing container (container half) on the side having the projecting member 415 is attached to the second screw 44. Can be retracted by rotating about. When the shutter 101 is mounted on the developing device, the shutter 101 is inserted into a gap W (see FIG. 8) between the projection members 411 and 412 and the projection member 413, and then the holes of the shutter 101 are engaged with the projection members 411 and 412. Combine. 5 and 6, the protrusion members 413 and 414 are omitted. Further, since the projection member 412 overlaps with the projection member 411, it cannot be seen in the drawing.
[0040]
As described above, in this embodiment, by operating the lever 103 from the front of the apparatus main body, the shutter 101 closing the recovery hole R at the bottom of the developing device is opened and closed, and the deteriorated developer Since it is not necessary to open and close the shutter or cap below the developing device after inserting the hand into the apparatus main body and placing the collection container 104 at a predetermined position, Since it is not necessary to perform a troublesome operation (operation) such as detaching and moving the apparatus to another collection place in the apparatus main body, the developer can be easily collected without fear of spilling the developer. Therefore, workability is significantly improved. Further, it is advantageous in terms of cost and maintainability.
[0041]
Next, a third embodiment of the present invention will be described with reference to FIGS. 10 and 11 are views of the developing device viewed from below. FIG. 10 shows a state where the shutter 101 is closed, and FIG. 11 shows a state where the shutter 101 is open. In the second embodiment, the lever 103 is configured to perform a linear operation (sliding operation). However, in the present embodiment, the lever 103 is configured to perform a rotating operation. Is different from Since other configurations are the same as those of the second embodiment, parts and members corresponding to those in FIGS. 6 to 9 are denoted by the same reference numerals and description thereof will be omitted unless necessary.
[0042]
Also in this embodiment, the shutter 101 is held by the protrusion members 411 and 412, as in the second embodiment. On the other hand, the lever 103 is rotatably supported by a rotation support shaft 416 protruding from the developing container 41 using a tension ring or the like. The protruding members 417 and 418 function as stoppers of the lever 103 when the shutter 101 is closed and open, respectively.
[0043]
The procedure for collecting the deteriorated developer is the same as that in the second embodiment, and the description is omitted here.
[0044]
In the above embodiment, the case where the present invention is applied to an electrophotographic color image forming apparatus has been described. However, the present invention is not limited to this, and various other configurations of electrophotographic color or monochromatic It goes without saying that the present invention can be equally applied to a (black and white) image forming apparatus and an image forming apparatus of an electrostatic recording system or the like.
[0045]
【The invention's effect】
As described above, according to the collecting method of the present invention, the attaching step of attaching the collecting container for collecting the developer in a state where the drawer unit that can be pulled out with respect to the image forming apparatus main body is pulled out, Since it has a moving step of moving the drawer unit so as to be located below the collecting hole, and a collecting step of collecting the developer from the collecting hole to the collecting container, the operator can move the drawer unit inside the image forming apparatus main body. The developer can be collected without performing a troublesome operation such as putting a hand in the printer.
[0046]
Further, according to the image forming apparatus of the present invention, the drawer unit is provided with the attaching portion to which the collecting container for collecting the developer is attached when pulled out, and collects the developer.ForWhen the drawer unit with the collection container is moved, the collection container is provided at the bottom of the developing device.WasSince it is configured to have a positioning means for positioning the position of the collection container so as to be located below the collection hole, the developer can be used without troublesome work such as inserting a hand into the image forming apparatus main body. Can be collectedit can.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view illustrating a configuration of a main part of an image forming apparatus according to a first embodiment of the present invention when a developer is collected.
FIG. 2 is a schematic cross-sectional view illustrating a configuration of a main part during normal image formation of the image forming apparatus according to the first embodiment of the present invention.
FIG. 3 is a schematic sectional view illustrating a configuration of a main part when a developer collection container of the image forming apparatus according to the first embodiment of the present invention is set.
FIG. 4 is a schematic sectional view showing a modification of the positioning means used in the image forming apparatus according to the first embodiment of the present invention.
FIG. 5 is a schematic cross-sectional view illustrating a configuration of a main part of an image forming apparatus according to a second embodiment of the present invention when a developer is collected.
FIG. 6 is a schematic cross-sectional view illustrating a configuration of a main part during normal image formation of the image forming apparatus according to the second embodiment of the present invention.
FIG. 7 is a schematic bottom view of a part of a developing device used in an image forming apparatus according to a second embodiment of the present invention.
FIG. 8 is a schematic bottom view of a part of a developing device used in an image forming apparatus according to a second embodiment of the present invention.
FIG. 9 is a cross-sectional view of FIG. 7 taken along line 9-9.
FIG. 10 is a schematic bottom view of a part of a developing device used in an image forming apparatus according to a third embodiment of the present invention.
FIG. 11 is a schematic bottom view of a part of a developing device used in an image forming apparatus according to a third embodiment of the present invention.
FIG. 12 is a schematic sectional view showing an example of a conventional electrophotographic color image forming apparatus.
FIG. 13 is a schematic sectional view showing an example of a developing device used in the conventional electrophotographic color image forming apparatus shown in FIG.
FIG. 14 is a development view of a main part of the developing device of FIG. 13 for explaining a mode of collecting the developer.
[Explanation of symbols]
8 Recording material carrying belt
10 Recording material carrying belt support
11, 12 Rail members
41 Developing container
42 Developing sleeve
43,44 screw
99 Centering plate
101 shutter
102 Sealing member
103 lever
104 Collection container
110 screws
411-415 Projection member
416 Rotating spindle
417, 418 Projection member
A Holes in the centering plate
D developer
M, N Projection of collection container
Q Supply port
R recovery hole

Claims (3)

In a collection method of collecting a developer from a collection hole provided at a bottom of a developing device that develops a latent image formed on an image carrier with a developer,
An attaching step of attaching a collection container for collecting the developer in a state where the drawer unit that can be pulled out with respect to the image forming apparatus main body is pulled out, and mounting the drawer unit such that the collection container is located below the collection hole. A collecting method, comprising: a moving step of moving; and a collecting step of collecting a developer from the collecting hole to the collecting container. An image carrier, a developing device for developing a latent image formed on the image carrier with a developer, and a drawer unit that can be pulled out with respect to the image forming apparatus main body, form an image on a recording material Image forming apparatus,
The drawer unit includes an attachment portion to which a collection container for collecting the developer when the drawer is in the pulled-out state is attached,
When moving the drawer unit to which the collection container is attached for collecting the developer, the position of the collection container is set so that the collection container is located below the collection hole provided at the bottom of the developing device. An image forming apparatus comprising positioning means for positioning. 3. The image forming apparatus according to claim 2 , wherein the developer includes a toner and a carrier, and recovers the deteriorated developer into the recovery container from the recovery hole.

Images