JP3997116B2 - Cleaning device and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cleaning device that removes residual developer remaining on the surface of an image carrier and an image forming apparatus including such a cleaning device.
[0002]
[Prior art]
Conventionally, in this type of electrophotographic image forming apparatus, a toner image electrostatically formed on the surface of a photoreceptor as an image carrier is also electrostatically transferred to a transfer material mainly made of paper. An image forming apparatus is common.
[0003]
In such an image forming apparatus, the residual toner (residual developer) that is not transferred to the transfer material side at the time of transfer but remains on the photoconductor is sufficiently cleaned each time for the next image formation. is required. As a cleaning device for that purpose, for example, the one shown in FIG. 11 has already been widely put into practical use. In this cleaning device, a cleaning blade 107 made of an elastic material such as urethane rubber is pressed against the surface of the photoreceptor 115 to remove residual toner.
[0004]
When removing the residual toner, the toner leaks from the cleaner container 125 and the scattered toner floats. Therefore, a flexible member 101 such as a urethane sheet is usually placed under the cleaner container 125 and the photosensitive member 115. To prevent toner leakage from the cleaner container 125. Further, the seal member 104 is disposed at the end of the cleaner container 125, and both ends of the flexible member 101 are sandwiched between the seal member 104 and the photoconductor 115, thereby preventing toner leakage from the end of the cleaner container 125. ing. Hereinafter, the flexible member 101 is referred to as a “rake sheet”.
[0005]
Since the rake sheet 101 is a consumable item, it must be replaced at a certain time. The cleaning device having such a configuration can be attached to and detached from the photosensitive member 115, and replacement of the scoop sheet 101 is performed outside the apparatus after the cleaning device is separated from the photosensitive member 115 and extracted from the main body of the image forming apparatus. (FIG. 12).
[0006]
[Problems to be solved by the invention]
However, when performing maintenance on the rake sheet 101, toner may be scattered when the cleaning device is pulled out from the main body, and the inside of the machine may be contaminated. There is also a possibility that. The operation of removing the cleaning device from the main body is complicated, and a large work space must be secured.
[0007]
On the other hand, if the cleaning device is changed from a movable type to a fixed type, the configuration becomes simple and the cost is low, so that the merit is great. Further, since only the scooping sheet 101 can be detached from the cleaning device, the maintainability is improved and a large work space is not required.
[0008]
However, as described above, the end portion of the rake sheet 101 is sandwiched between the seal member 104 fixed to the cleaner container 125 and the photosensitive member 115 (FIG. 13). Therefore, while the photosensitive member 115 and the cleaning device are fixed, the rake sheet 101 can be removed, but it is not possible to insert the tip of the rake sheet 101 between the seal member 104 and the photosensitive member 115 when attaching. This is not possible, and the leading edge breaks (incorrect attachment) as shown in FIG.
[0009]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cleaning device having a structure in which a flexible member can be easily replaced without removing the cleaning device body, and such a cleaning device. Another object of the present invention is to provide an image forming apparatus.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides:
A container having an opening facing the surface of the image carrier;
A cleaning member for scraping off the residual developer on the surface of the image carrier at the upper part of the opening;
A flexible member that slidably contacts the image carrier at the bottom of the opening and receives the scraped residual developer;
In a cleaning device comprising a sealing member that seals a gap between the device and the surface of the image carrier on both sides of the opening,
The seal member is composed of a first seal member disposed at both ends of the cleaning member, and a second seal member disposed at both ends of the flexible member, and
The receiving member unit having the flexible member and the second seal member is detachably provided to the main body unit having the container, the cleaning member, and the first seal member.
[0011]
The second seal member is preferably disposed in contact with both ends of the flexible member.
[0012]
The second seal member is preferably in close contact with the first seal member when the receiving member unit is mounted on the main body unit.
[0013]
The receiving member unit preferably includes a third seal member that seals a gap between the main body unit and the receiving member unit.
[0014]
While engaging a mounting claw provided in one of the receiving member unit and the main body unit and a mounting hole provided in the other,
By fitting a boss provided in one of the receiving member unit and the main unit and a positioning hole provided in the other,
The receiving member unit is preferably positioned and fixed to the main body unit.
[0015]
It is preferable that the attachment hole has a wide portion into which the attachment claw is inserted and a narrow portion with which the attachment claw is engaged by sliding the receiving member unit.
[0016]
In addition, the image forming apparatus of the present invention includes any one of the above-described cleaning devices.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Exemplary embodiments of the present invention will be described in detail below with reference to the drawings. This cleaning device is suitable for use in a cleaner that removes residual toner remaining on the surface of a photoreceptor in an electrophotographic image forming apparatus such as a laser beam printer, a copying machine, or a laser facsimile.
[0018]
It should be noted that the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments are intended to limit the scope of the present invention only to those unless otherwise specified. is not.
[0019]
First, the overall configuration of the image forming apparatus according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic sectional view of the image forming apparatus.
[0020]
The image forming apparatus shown in FIG. 1 forms an electrostatic latent image on a photosensitive member as an image carrier, develops the latent image with a developer (toner), and transfers it to a sheet to form a full color image. This is an electrophotographic color image forming apparatus.
[0021]
An image reading unit is provided on the upper part of the apparatus main body, and the original S placed on the original table glass 30 is exposed and scanned by the exposure lamp 31 so that the reflected light images from the original S are mirrors 12a, 12b, 12c. , And the lens 13 to focus on the full color sensor 14 to obtain a color separation image signal.
[0022]
The color-separated image signal is processed by a video processing unit through an amplifier circuit (not shown) and sent to an image forming unit.
[0023]
The image forming unit includes a photoreceptor 15 that is an image carrier. Further, around the photoconductor 15, a pre-exposure lamp 16, a corona charger 17, a laser exposure optical system 18 as an exposure means, a potential sensor 19, a cleaning device 24, a fixed black developing device 21K, and three rotatable units Color developing units 20Y, 20M, and 20C and an intermediate transfer member 9 are disposed. Here, the developing devices 20Y, 20M, and 20C use non-magnetic toner, and the developing device 21K uses magnetic toner.
[0024]
When an image formation start signal is input to the image forming unit, the photoconductor 15 is rotationally driven in the direction of arrow A by a driving unit (not shown). Then, the residual potential of the photoconductor 15 is neutralized by the pre-exposure lamp 16 and uniformly charged by the corona charger 17.
[0025]
In the laser exposure optical system 18, the image signal from the image reading unit is converted into an optical signal by a laser output unit (not shown), and the converted laser beam is reflected by the rotary polygon mirror 18a and passes through the lens 18b and the mirror 18c. And projected onto the cylindrical surface of the photoreceptor 15. In this way, a light image is irradiated for each separated color, and an electrostatic latent image is formed on the photoreceptor 15.
[0026]
The three rotating developing devices 20Y, 20M, and 20C are detachably held by a developing rotary 23 that rotates about a rotating shaft 22, respectively. At the time of image formation, each developing device is rotated around the rotating shaft 22 while being held by the developing rotary 23, the predetermined developing device stops at a position facing the photoconductor 15, and the developing sleeve is further moved to the photoconductor. After being positioned so as to face 15 with a small interval, a visible image is formed corresponding to the electrostatic latent image on the photoreceptor 15.
[0027]
At the time of color image formation, the development rotary 23 rotates every rotation of the intermediate transfer member 9, and the development process is performed in the order of the magenta developing unit 20M, the yellow developing unit 20Y, the cyan developing unit 20C, and then the black developing unit 21K.
[0028]
Since the intermediate transfer member 9 receives the toner image on the photosensitive member 15 visualized by each developing device during the color image forming operation four times (each image of four colors of M, Y, C, and K), the photosensitive member is subjected to multiple transfer. Rotate in the direction of arrow B in synchronization with the outer peripheral speed of 15. The intermediate transfer body 9 that has undergone multiple transfer nips and conveys the transfer material 11 by a transfer roller 10 to which a voltage is applied, thereby simultaneously transferring multiple color toner images on the intermediate transfer body 9 onto the transfer material 11. The transfer material 11 after the transfer is sent to a fixing device which is the next process.
[0029]
The transfer material 11 holding the toner image is conveyed by a fixing roller 26 and a pressure roller 27 and is subjected to heat and pressure. As a result, the toner is fixed to the transfer material 11.
[0030]
Next, the configuration of the cleaning device according to the present embodiment will be described with reference to FIG. FIG. 2 is a schematic sectional view of the cleaning device.
[0031]
The cleaning device includes a main unit D and a rake sheet unit (receiving member unit) E that is detachable from the main unit D.
[0032]
The main unit D generally includes a cleaner container 25 having an opening 25b facing the surface of the photoconductor 15 on a side surface thereof, and a cleaning blade 7 as a cleaning member that scrapes off residual toner on the surface of the photoconductor 15 above the opening 25b. And a container end seal (first seal member) 4 disposed at both ends of the cleaning blade 7.
[0033]
The cleaner container 25 is a box that forms an outline of the cleaning device. The cleaner container 25 accommodates a cleaning roller 7, a magnet roller 5, a waste toner conveying screw 6, and other components described later, and a residual recovered from the photoreceptor 15. Plays the role of accepting toner.
[0034]
The cleaning blade 7 made of urethane rubber is fixed to a blade swing plate 33, and the blade swing plate 33 is supported so as to be swingable about a swing fulcrum shaft 34. Further, a pressure spring 32 is stretched around the blade swing plate 33, and the cleaning blade 7 is urged against the photosensitive member 15 with a predetermined pressure by the spring force of the pressure spring 32.
[0035]
One edge of one edge of the cleaning blade 7 attached to the frame is pressed against the surface of the photoconductor 15 to scrape off the residual toner after transfer.
[0036]
A magnet roller 5 is disposed on the upstream side of the cleaning blade 7 in the traveling direction of the photoconductor 15 and is driven in the same direction as the photoconductor 15 as indicated by an arrow C direction. When magnetic toner and non-magnetic toner are supplied by the developing devices 20Y, 20C, 20M, and 21K, a part of the collected magnetic toner is fixed on the surface of the magnet roller 5 by the doctor blade 28 and has a constant thickness. The magnetic brush 5a which is a layer is formed.
[0037]
The doctor blade 28 is arranged so that the thickness of the formed toner layer is appropriately larger than the minimum distance between the photoconductor 15 and the magnet roller 5, and the toner layer faces the photoconductor 15 as the magnet roller 5 rotates. The position is reached and the surface of the photoconductor 15 is rubbed reliably. The collected toner that does not form the magnetic brush 5 a is scraped off by the doctor blade 28 and discharged to the outside by the waste toner conveying screw 6 through the communication hole 29.
[0038]
The nonmagnetic toner detached while the magnetic brush 5 a of the magnet roller 5 rotates from the doctor blade 28 to the photosensitive member 15 falls under the magnet roller 5. The inner wall surface of the cleaner container 25 under the magnet roller 5 has an inclination, and the dropped nonmagnetic toner is conveyed to the waste toner conveying screw 6 by its own weight.
[0039]
The rake sheet unit E is attached to the lower portion of the cleaner container 25, and generally includes a rake sheet 1 which is a flexible member, and end seals (second seal members) disposed at both ends of the rake sheet 1. 3).
[0040]
The rake sheet 1 slidably contacts the surface of the photoreceptor 15 at the lower part of the opening 25b of the cleaner container 25 (below the cleaning blade 7), receives residual toner scraped off by the cleaning blade 7, and receives the cleaner from the opening 25b. The collected toner is introduced into the container 25.
[0041]
Further, on both sides of the opening 25b, the container end seal 4 attached to the main unit D and the end seal 3 attached to the rake sheet unit E are crushed between the cleaning device and the photoconductor 15. The gap between the apparatus and the photoconductor 15 is sealed.
[0042]
As a result, the nonmagnetic toner separated from the magnet roller 5 and the scattered nonmagnetic toner do not spill from the cleaner container 25.
[0043]
Next, the configuration of the rake sheet unit E according to the present embodiment will be described with reference to FIG. FIG. 3 is a schematic perspective view of the rake sheet unit E. FIG.
[0044]
The rake sheet unit E is configured by attaching a rake sheet 1, an end seal 3 and a seal material (third seal member) 8 to a rake sheet support plate 2 as a support.
[0045]
The rake sheet support plate 2 is made by bending a sheet metal, and has a bottom 2b along the bottom surface of the cleaner container 25, and a side surface on which the opening 25b of the cleaner container 25 is provided from the longitudinal edge of the bottom 2b. A seat support portion 2c that rises along, an end seal support portion 2d that stands on both sides of the seat support portion 2c, and a positioning portion that stands along the end surface of the cleaner container 25 from the short edge of the bottom portion 2b. 2e. The bottom 2b is provided with a convex mounting hole 2a, and the positioning portion 2e is provided with a plurality (two in this embodiment) of positioning holes 2f.
[0046]
A rake sheet 1 made of a flexible material such as a urethane sheet is fixed to the outer surface side of the sheet support portion 2c of the rake sheet support plate 2, and the tip portion of the rake sheet 1 (projected from the sheet support portion 2c). The part) is a free end that can be freely deformed. On the other hand, the sealing material 8 is fixed to the inner surface side of the sheet support portion 2c. The lengths of the rake sheet 1 and the sealing material 8 in the longitudinal direction are substantially the same, and are longer than the width of the opening 25 b of the cleaner container 25.
[0047]
Further, the end seal 3 is fixed to the outer surface side of the end seal support portion 2 d of the rake sheet support plate 2. Since the end seal support portion 2d is arranged on the inner side (cleaner container side) than the sheet support portion 2c, the end seal 3 is disposed so as to be in contact with both ends of the rake sheet 1 and the seal material 8.
[0048]
4 and 5 are views before and after attaching the rake sheet unit E to the main unit D. FIG. FIG. 4 shows the state before attachment, and FIG. 5 shows the state after attachment.
[0049]
As shown in FIG. 4, the cleaning blade 7 is disposed above the opening 25b of the cleaner container 25, and the container end seal 4 is disposed on both sides of the opening 25b. When the rake sheet unit E is attached here, as shown in FIG. 5, the end seals 3 and the container end seals 4 at both ends of the rake sheet unit E are in close contact with each other without any gap (indicated by “XX” in the figure). The part is the combined part of both seals.)
[0050]
FIGS. 6 to 10 show attachment procedure diagrams of the rake sheet unit E. FIG. 6 to 10, only a part of the cleaner container 25 and the scooping sheet support plate 2 are shown, and other members are omitted for easy understanding.
[0051]
As shown in FIG. 6, a mounting claw 25 a is provided on the bottom surface of the cleaner container 25 of the main unit D, and a positioning boss 35 is provided on the end face of the cleaner container 25. In addition, when attaching the rake sheet unit E, work is performed from the right side in the drawing, that is, the side where the boss 35 is disposed. Therefore, in the following description, the side where the boss 35 is disposed is referred to as “front”, The side on which the mounting claws 25a are disposed is described as “rear”.
[0052]
First, as shown in FIG. 7, the attachment hole 2a at the rear of the rake sheet unit E is aligned with the attachment claw 25a of the cleaner container 25, and the attachment claw 25a is inserted into the wide part of the attachment hole 2a. Install the rear part. At this time, the rake sheet unit E is attached with a slight angle with respect to the main unit D so that the rear part is high and the front part is low.
[0053]
Next, the rake sheet unit E is slid toward the front side in the longitudinal direction, the attachment claw 25a is fitted into the narrow portion of the attachment hole 2a, and the attachment claw 25a and the attachment hole 2a are engaged (FIG. 8). Thereby, the attachment claw 25a can be prevented from coming off.
[0054]
Then, the front portion (positioning portion 2e side) of the rake sheet support plate 2 is lifted, and the positioning holes 2f of the rake sheet support plate 2 are aligned with the bosses 35 provided on the front end surface of the cleaner container 25 (FIG. 9). ) And slide in the opposite direction (the rear side in the longitudinal direction) to fit the boss 35 and the positioning hole 2f (FIG. 10).
[0055]
In this way, the rake sheet unit E has one end (rear part) due to the fitting between the attachment claw 25a and the narrow part of the attachment hole 2a and the gap between the bottom surface of the cleaner container 25 and the front end of the attachment claw 25a. On the other hand, the other end portion (front portion) is positioned and fixed by fitting the boss 35 and the positioning hole 2f.
[0056]
In addition, what is necessary is just to follow the procedure reverse to the above, when removing the scooping sheet unit E. FIG.
[0057]
According to the configuration of the present embodiment described above, the rake sheet 1 is unitized and can be attached to and detached from the cleaning device main body. Therefore, when the rake sheet 1 is deteriorated due to wear or the like, the rake sheet 1 can be easily and space-savingly replaced. This makes it possible to maintain high-quality image formation.
[0058]
Further, a seal member that seals the gap between the cleaning device and the photoconductor 15 at both sides of the opening 25b is composed of the container end seal 4 and the end seal 3, and the end seal 3 is a scoop sheet. Since the rake sheet 1 is provided on the unit E side, the tip of the rake sheet 1 is not bent when the rake sheet 1 is inserted between the cleaner container 25 and the photosensitive member 15, and the rake sheet 1 can be easily removed without removing the main body of the cleaning device. Can be exchanged. As a result, since the cleaning device can be fixed, the configuration is simple and the cost is low.
[0059]
Further, since the end seal 3 is disposed in contact with both ends of the rake sheet 1, the rake sheet 1 maintains an appropriate contact pressure with respect to the photoreceptor 15 while sliding both ends of the rake sheet 1 on the end seal 3. Will come into sliding contact. Thereby, toner leakage from the end of the rake sheet 1 can be prevented, and the residual toner scraped off by the cleaning blade 7 can be reliably received by the rake sheet 1.
[0060]
Further, since the end seal 3 is in close contact with the container end seal 4 when the rake sheet unit E is mounted on the main unit D, the end seal 3 is disposed between the end seal 3 and the container end seal 4 or on both sides of the opening 25b. Toner leakage from the portion can be reliably prevented.
[0061]
Further, since the sealing material 8 that seals the gap between the main unit D and the scooping sheet unit E is provided in the scooping sheet unit E, toner leakage from the lower portion of the cleaner container 25 can be reliably prevented.
[0062]
In addition, the rake sheet unit E is positioned and fixed to the main unit D by engaging the mounting claw 25a with the mounting hole 2a and fitting the boss 35 with the positioning hole 2f. The rake sheet unit E can be easily attached and detached without using a fixing tool such as the above.
[0063]
Also, the mounting claw 25a and the mounting hole 2a are arranged at a position where the side face provided with the opening 25b is avoided and visible from the front side of the machine, such as the bottom surface of the apparatus and the boss 35 and positioning hole 2f are the front surface of the apparatus. Therefore, the scooping sheet unit E can be easily replaced even when the cleaning device is still attached to the image forming apparatus main body.
[0064]
Further, since the sliding direction when engaging the mounting claw 25a and the mounting hole 2a and the direction when engaging the boss 35 and the positioning hole 2f are substantially the same, the rake sheet unit E can be attached and detached and positioned. It can be done very easily.
[0065]
In the present embodiment, the mounting claws 25a and the bosses 35 are provided on the main unit D side, and the mounting holes 2a and the positioning holes 2f are provided on the scooping sheet unit E side. A boss may be provided on the scooping sheet unit E side.
[0066]
In the present embodiment, the configuration using the magnet roller is described, but the effect of the present invention is not limited to this configuration.
[0067]
【The invention's effect】
As described above, according to the present invention, the flexible member can be easily replaced without removing the cleaning device body.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of an image forming apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic sectional view of a cleaning device according to an embodiment of the present invention.
FIG. 3 is a schematic perspective view of a rake sheet unit.
FIG. 4 is a schematic view showing a state before the rake sheet unit is attached.
FIG. 5 is a schematic view showing a state after the rake sheet unit is attached.
FIG. 6 is an explanatory view showing a procedure 1 for attaching a rake sheet unit.
FIG. 7 is an explanatory view showing a rake sheet unit attachment procedure 2;
FIG. 8 is an explanatory diagram showing a rake sheet unit attachment procedure 3;
FIG. 9 is an explanatory view showing a rake sheet unit attachment procedure 4;
FIG. 10 is an explanatory view showing a procedure 5 for attaching a rake sheet unit.
FIG. 11 is a schematic sectional view of a conventional cleaning device.
FIG. 12 is a diagram for explaining a state in which a rake sheet is replaced in a conventional cleaning device.
FIG. 13 is a schematic view of a main part showing an end portion of a rake sheet of a conventional cleaning device.
FIG. 14 is a view for explaining the leading edge folding of the rake sheet.
[Explanation of symbols]
1 Rake sheet (flexible member)
2 Sheet support plate 2a Mounting hole 2b Bottom portion 2c Sheet support portion 2d End seal support portion 2e Positioning portion 2f Positioning hole 3 End seal (second seal member)
4 Container end seal (first seal member)
5 Magnet roller 5a Magnetic brush 6 Waste toner conveying screw 7 Cleaning blade (cleaning member)
8 Sealing material (third sealing member)
9 Intermediate transfer member 10 Transfer roller 11 Transfer material 12a, 12b, 12c, mirror 13 lens 14 full color sensor 15 photoconductor (image carrier)
16 Pre-exposure lamp 17 Corona charger 18 Laser exposure optical system 18a Rotating polygon mirror 18b Lens 19 Potential sensor 20Y Developer (yellow developer)
20C developer (cyan developer)
20M Developer (Magenta Developer)
21K developer (black developer)
22 Rotating shaft 23 Development rotary 24 Cleaning device 25 Cleaner container 25a Mounting claw 25b Opening portion 26 Fixing roller 27 Pressing roller 28 Doctor blade 29 Communication hole 30 Platen glass 31 Exposure lamp 32 Pressing spring 33 Blade swing plate 34 Shaking Dynamic fulcrum shaft 35 Boss D Main unit E Rake sheet unit (receiving member unit)
S manuscript

Claims (7)

A container having an opening facing the surface of the image carrier;
A cleaning member for scraping off the residual developer on the surface of the image carrier at the upper part of the opening;
A flexible member that slidably contacts the image carrier at the bottom of the opening and receives the scraped residual developer;
In a cleaning device comprising a sealing member that seals a gap between the device and the surface of the image carrier on both sides of the opening,
The seal member is composed of a first seal member disposed at both ends of the cleaning member, and a second seal member disposed at both ends of the flexible member, and
A cleaning apparatus, wherein a receiving member unit having the flexible member and the second seal member is detachably provided to a main body unit having the container, the cleaning member, and the first seal member. The cleaning apparatus according to claim 1, wherein the second seal member is disposed in contact with both ends of the flexible member. The cleaning device according to claim 1, wherein the second seal member is in close contact with the first seal member when the receiving member unit is attached to the main body unit. The cleaning device according to claim 1, wherein the receiving member unit includes a third seal member that seals a gap between the main body unit and the receiving member unit. While engaging a mounting claw provided in one of the receiving member unit and the main body unit and a mounting hole provided in the other,
By fitting a boss provided in one of the receiving member unit and the main unit and a positioning hole provided in the other,
The cleaning device according to claim 1, wherein the receiving member unit is positioned and fixed to the main body unit. The cleaning device according to claim 5, wherein the attachment hole includes a wide portion into which the attachment claw is inserted and a narrow portion into which the attachment claw is engaged by sliding the receiving member unit. . An image forming apparatus comprising the cleaning device according to claim 1.

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