JP3835549B2 - Latent image carrier cleaning device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a latent image holding member cleaning device for cleaning toner remaining on the surface of a latent image holding member after a transfer process of an electrophotographic printing machine.
[0002]
[Prior art]
As a conventional technique of this type of cleaning device, for example, as disclosed in Patent Document 1, a cleaning brush is brought into contact with the surface of a photosensitive drum as a latent image holding member, and the cleaning brush is brought into contact with the contact surface. There is known a configuration in which they are rotated so as to face in opposite directions.
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 5-66705 (FIG. 1, paragraph (0011))
[0004]
[Problems to be solved by the invention]
The conventional cleaning device using the cleaning brush can satisfactorily clean the surface of the photosensitive drum in the electrophotographic printer using dry toner, but the photosensitive drum in the electrophotographic printer using wet toner. The cleaning effect is low, and innumerable streaks remain in the circumferential direction on the surface of the photosensitive drum, which is an obstacle to good image formation in the next image forming process.
[0005]
The present invention has been made in view of the above, and even in an electrophotographic printing machine using a wet toner, the surface of the latent image holding member after the transfer process is reliably cleaned to form an image in the next process. An object of the present invention is to provide a latent image holding member cleaning device capable of preventing the occurrence of a failure.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a latent image holding member cleaning device according to the present invention is provided in a latent image holding member cleaning device provided so as to face the peripheral surface of a latent image holding member and clean the peripheral surface thereof. Upper and lower cleaning rollers that rub against the peripheral surface of the holding body at positions displaced in the vertical direction are provided so as to rotate reversely with respect to the peripheral surface of the latent image holding body. The roller is configured to have a liquid-absorbing rubbing body laminated on the shaft body, and the lower cleaning roller is laminated to a cylinder having a large number of small holes in the peripheral wall. In addition, a suction pipe is connected to the hollow portion of the cylinder, and a spray nozzle for spraying the cleaning liquid toward the upper cleaning roller is provided.
[0007]
In the latent image holding body cleaning device, a pipe having upper and lower cleaning rollers and a spray nozzle is provided in the frame body, the frame body can be moved in the perspective direction with respect to the latent image holding body, A drainage reservoir whose bottom surface is close to the outer periphery of the lower cleaning roller is provided at the lower part of the frame so that the drainage collected in the drainage pool is sucked by the peripheral surface of the lower cleaning roller. The side cleaning roller was supported on the frame so that its position could be adjusted in the perspective direction with respect to the latent image holding member.
[0008]
[Operation]
According to the rotation of the latent image holder, the upper and lower cleaning rollers are rotated in reverse while being rubbed. At this time, the cleaning liquid is sprayed from the spray nozzle toward the upper cleaning roller, and the upper cleaning roller cleans the surface of the latent image holding member by the rubbing of the rubbing material and the cleaning liquid.
[0009]
The cleaning liquid impregnated in the upper cleaning roller is dropped on the lower cleaning roller, and the surface of the latent image holding member is also cleaned by this lower cleaning roller by the same action as the upper cleaning roller. This cleaning action is brought into a contact state by bringing the frame body closer to the latent image holding body side, and is brought into a separated state by moving away from the frame body. In this separated state, spraying of the cleaning liquid is stopped.
[0010]
The cleaning liquid impregnated in the lower cleaning roller is sucked into the cylinder of the lower cleaning roller and discharged to the outside. Also, the cleaning liquid collected at the lower part of the frame is sucked into the cylinder from the rubbing material surface of the lower cleaning roller and discharged from the liquid storage.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0012]
FIG. 1 shows a main part of an electrophotographic printer equipped with a latent image holding member cleaning device 1 according to the present invention and using wet toner. A photosensitive drum 2 as an example of a latent image holding member is disposed around the photosensitive drum 2. From the rolling contact portion (transfer portion) of the intermediate transfer roller 3 to the downstream side in the rotation direction, the latent image carrier cleaning device 1 and the static eliminator 4, a plurality of sets, for example, first and second image forming devices 5a and 5b. The surplus solvent removing device 6 and the drying device 7 are provided.
[0013]
The electrophotographic printing machine is disposed symmetrically about one place on the peripheral surface of the intermediate transfer roller 3, and the continuous paper W passes between the intermediate transfer rollers 3, whereby double-sided printing is performed on this. ing. It is also possible to perform single-sided printing by rolling the impression cylinder onto the intermediate transfer roller 3.
[0014]
Each set of the image forming apparatuses 5a and 5b has substantially the same configuration, and the charger device 8, the exposure device (latent image forming device) 9, the developing device 10, and the squeeze roller 11 are arranged from the upstream side in the rotation direction of the photosensitive drum 2. They are arranged in order.
[0015]
In this electrophotographic printer, as the photosensitive drum 2 rotates, the toner and potential remaining on the surface of the photosensitive drum 2 are removed by the latent image holding cleaning device 1 and the charge removal device 4. Next, toner images for two colors are formed by the first and second image forming apparatuses 5a and 5b.
[0016]
In each of the image forming apparatuses 5a and 5b at this time, the surface of the photosensitive drum 2 is charged to a predetermined voltage by the charger device 8, and a laser beam image-modulated by the exposure device 9 is irradiated on the surface to statically. An electrostatic latent image is formed, and the electrostatic latent image is developed into a toner image by the developing device 10 using wet toner. Since the developing toner at this time is supplied to the surface of the photosensitive drum 2 together with the solvent (liquid developer), the excess solvent at this time is removed by the squeeze roller 11.
[0017]
In such an electrophotographic printing machine, the excess solvent cannot be removed by the squeeze rollers 11 in the image forming apparatuses 5a and 5b, and the surface of the photosensitive drum 2 is still dried by the image forming apparatuses 5a and 5b. Then, there is an excess solvent that cannot be removed. The surplus solvent removing device 6 removes surplus solvent existing on the downstream side of the image forming apparatuses 5a and 5b.
[0018]
Next, the configuration of the latent image carrier cleaning device 1 according to the present invention will be described with reference to FIG.
[0019]
In the figure, reference numerals 15 and 16 denote upper and lower cleaning rollers arranged opposite to the photosensitive drum 2 in the rotational direction and in the vertical direction. The upper cleaning roller 15 located on the upstream side in the rotation direction of the photosensitive drum 2 has a structure in which a sponge layer 18 a is laminated on the outer periphery of the shaft 17, and both ends of the shaft 17 are rotatably supported by brackets 19 and 19. ing.
[0020]
The lower cleaning roller 16 located on the downstream side in the rotation direction of the photosensitive drum 2 has a structure in which a sponge layer 18b is laminated on a cylinder 21 having a large number of small holes on the peripheral wall. The brackets 19 and 19 are rotatably supported. One shaft portion of the cylinder 21 is hollow, and a suction pipe 22 communicating with a suction device (not shown) is connected to the hollow shaft portion.
[0021]
Brackets 19, 19 that support the upper and lower cleaning rollers 15, 16 are fixed inside a frame body 23 that is formed in a U-shaped cross section with the side facing the photosensitive drum 2 open. A hollow spray tube 24 is provided in the frame 23 in parallel with the upper cleaning roller 15 so that both ends thereof are fixed to the brackets 19, 19. A plurality of spray nozzles 25 are arranged in the axial direction of the spray tube 24. Is provided toward the upper cleaning roller 15. A cleaning liquid supply pipe 26 is connected to both ends (or one end) of the spray pipe 24.
[0022]
One shaft portion in the axial direction of both the cleaning rollers 15 and 16 protrudes to the outside of the bracket 19, and gears 27 and 28 are fixed to the respective portions. The two gears 27 and 28 mesh with a drive gear 30 that is driven to rotate by a motor 29 supported by the frame body 23, and both the cleaning rollers 15 and 16 are rotated in the same direction as the photosensitive drum 2 by the driving of the motor 29. Accordingly, the outer circumferences of the cleaning rollers 15 and 16 are configured to run in the direction opposite to the running direction of the circumferential surface of the photosensitive drum 2, that is, reversely rotate.
[0023]
The frame body 23 having a U-shaped cross section includes an upper stay 23a, a lower stay 23b, and a back stay 23c. An arc-shaped drainage reservoir 31 facing the outer periphery of the lower cleaning roller 16 is provided at a portion facing the lower side of the lower cleaning roller 16 on the lower stay 23b.
[0024]
Of the two cleaning rollers 15, 16, the lower cleaning roller 16 can be adjusted in position relative to both the brackets 19, 19 with respect to the photosensitive drum 2.
[0025]
FIG. 6 shows the configuration. A bearing 32 that supports the cylinder 21 of the lower cleaning roller 16 is fitted into the bracket 19 and a U-shaped hole 33 that opens the photosensitive drum 2 side. The bearing 32 is moved to the photosensitive drum 2 side by pushing the bearing 32 with a push screw 34 that passes through and protrudes from the outside of the frame body 23, and the lower cleaning roller 16 contacts the photosensitive drum 2. Pressure is applied. The movement limit of the bearing 32 is adjusted by the protruding height of the protruding screw 35 provided on the lower side of the U-shaped hole 33.
[0026]
The upper stay 23a of the frame body 23 having a U-shaped cross section protrudes on both sides in the axial direction, and this portion extends in the axial direction of the photosensitive drum 2 on the front and rear frames 40a and 40b that support both ends of the photosensitive drum 2. The movable bodies 41a and 41b supported so as to be movable in a direction perpendicular to the right and left are detachably supported, and are coupled by fixing screws 42 and 42.
[0027]
Each moving body 41a, 41b is fitted to guide rods 43a, 43b provided on each frame 40a, 40b. The movable bodies 41a and 41b are connected to the piston rods of the cylinder devices 44a and 44b fixed to the frames 40a and 40b via brackets 45a and 45b. 23 moves toward or away from the surface of the photosensitive drum 2, that is, in a perspective direction. Reference numerals 46 and 46 denote stoppers for setting a movement limit in a direction in which this approaches the photosensitive drum 2. Each stopper 46 is constituted by a bolt that passes through one bracket 47, 47 that supports the guide rods 43a, 43b and is screwed into the moving bodies 41a, 41b. The movement limit is reached by contact. Therefore, the movement limit is adjusted by changing the screwing amount of the bolt.
[0028]
In the frame 23, upper and lower doctor blades 48 a and 48 b that contact the outer peripheral surfaces of the upper and lower cleaning rollers 15 and 16, and a photoreceptor doctor blade 48 c that contacts the surface of the photosensitive drum 2. Is provided.
[0029]
The operation of the latent image carrier cleaning device 1 having the above-described configuration will be described below. The latent image holding member cleaning device 1 is assembled to the frames 40a and 40b such that both ends of the frame body 23 are placed on both moving bodies 41a and 41b and fixed by fixing screws 42 and 42. Then, by extending the cylinder devices 44a and 44b, the frame body 23 moves forward, that is, moves in the direction of the photosensitive drum 2, and the upper and lower cleaning rollers 15 and 16 are moved to the respective sponge layers 18a and 18b. It is pressed against the photosensitive drum 2 with a predetermined pressing force. Positioning with respect to the photosensitive drum 2 at this time is performed by a stopper 46. At this time, the position of the lower cleaning roller 16 can be finely adjusted by the protruding length of the protruding screw 35 and the pressing of the pressing screw 34.
[0030]
By driving the motor 29 in this state, the cleaning rollers 15 and 16 are rotated reversely with respect to the surface of the photosensitive drum 2, and the surface of the photosensitive drum 2 is covered with the sponge layers 18 a and 18 b of the rollers 15 and 16. To be cleaned.
[0031]
At this time, the cleaning liquid fed to the spray pipe 24 at high pressure is sprayed toward the cleaning roller 15 above the spray nozzle 25, and the upper cleaning roller 15 is sensitized by the cleaning liquid together with the rubbing by the sponge layer 18a. The body drum 2 is cleaned. At this time, the cleaning liquid is scraped off by the photosensitive doctor blade 48c and absorbed by the sponge layer 18b of the lower cleaning roller 16. The lower cleaning roller 16 is also sensitized by the cleaning liquid together with the rubbing by the sponge layer 18b. The surface of the body drum 2 is cleaned. Then, the cleaning liquid impregnated in the sponge layer 18b of the lower cleaning roller 16 is sucked into the cylinder 21 through a small hole provided on the peripheral wall thereof, and discharged from the suction pipe 22 to the outside. Further, the cleaning liquid scattered in the frame body 23 is collected in a drainage reservoir 31 provided on the lower stay 23b, and is sucked into the lower cleaning roller 16 through the sponge layer 18b of the lower cleaning 16 from here. . The surfaces of the upper and lower cleaning rollers 15 and 16 are cleaned by doctor blades 48a and 48b in contact therewith.
[0032]
By shortening the cylinder devices 44a and 44b, the frame body 23 is retracted and the cleaning rollers 15 and 16 are separated from the photosensitive drum 2. In this state, the motor 29 is stopped and the supply of the cleaning liquid is stopped. The latent image carrier cleaning device 1 is in a resting state.
[0033]
For maintenance and inspection of the cleaning rollers 15 and 16 of the latent image holder cleaning device 1, the fixing screws 42 and 42 are removed to remove the frame body 23 from the moving bodies 41a and 41b, and then the frame body 23 is disassembled. Do.
[0034]
In the above configuration, a drainage port for discharging the drainage liquid stored in the bottom of the frame body 23 may be provided separately from the drainage pool. The sponge layers 18a and 18b stacked on the cleaning rollers 15 and 16 may be anything that has a function of being washed by rubbing and having an action when impregnated with a cleaning liquid. It may be a body.
[0035]
【The invention's effect】
According to the present invention, since the surface of the latent image holding member is cleaned by the two cleaning rollers using the cleaning liquid, the surface of the latent image holding member can be reliably cleaned without remaining toner. it can. The cleaning liquid used for this cleaning can be discharged without leaking outside the apparatus.
[Brief description of the drawings]
FIG. 1 is a schematic configuration explanatory view showing a main part of an electrophotographic printer using a latent image carrier cleaning device according to the present invention.
FIG. 2 is a cross-sectional view showing a main part of the latent image carrier cleaning device according to the present invention.
FIG. 3 is a partially broken sectional view showing a shaft portion in an expanded manner, as seen from the direction of arrow A in FIG. 2;
FIG. 4 is an operation explanatory view showing a separated state of the latent image carrier cleaning device.
FIG. 5 is a view taken in the direction of arrow B in FIG. 2;
FIG. 6 is a cross-sectional view showing a bearing portion of a lower cleaning roller.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Latent image holding body cleaning apparatus, 2 ... Photosensitive drum (latent image holding body), 3 ... Intermediate transfer roller, 4 ... Static elimination apparatus, 5a, 5b ... Image forming apparatus, 6 ... Excess solvent removal apparatus, 7 ... Drying Apparatus 8 charger apparatus 9 exposure apparatus 10 developing apparatus 11 squeeze roller
15, 16 ... upper and lower cleaning rollers, 17 ... shaft, 18a, 18b ... sponge layer (rubbing body), 19 ... bracket, 21 ... cylinder, 22 ... suction pipe, 23 ... frame, 23a ... upper stay 23b ... Lower stay, 23c ... Back stay, 24 ... Spray pipe, 25 ... Spray nozzle, 26 ... Cleaning liquid supply pipe, 27, 28, 30 ... Gear, 29 ... Motor, 31 ... Drainage reservoir, 32 ... Bearing, 33 ... U-shaped hole, 34 ... Push screw, 35 ... Projection screw,
40a, 40b ... frame, 41a, 41b ... moving body, 42 ... fixing screw, 43a, 43b ... guide rod, 44a, 44b ... cylinder device, 45a, 45b ... bracket, 46 ... stopper, 47 ... bracket, 48a, 48b, 48c ... Doctor blade.

Claims (4)

In the latent image holding member cleaning device provided to face the peripheral surface of the latent image holding member and cleaning the peripheral surface thereof,
An upper cleaning roller and a lower cleaning roller that are rubbed at a position shifted in the vertical direction on the peripheral surface of the latent image holding member are provided so that each rotates reversely with respect to the peripheral surface of the latent image holding member,
The upper cleaning roller has a structure in which a rubbing body having liquid absorbency is stacked on a shaft body, and the lower cleaning roller is made of a rubbing body having liquid absorption in a cylinder having a large number of small holes in the peripheral wall. And a structure in which a suction pipe is connected to the hollow portion of the cylinder,
A latent image carrier cleaning apparatus, comprising a spray nozzle for spraying a cleaning liquid toward the upper cleaning roller. 2. The latent image according to claim 1, wherein a pipe having upper and lower cleaning rollers and a spray nozzle is provided in the frame body, and the frame body is movable in a perspective direction with respect to the latent image holding body. Holder cleaning device. The bottom of the frame is provided with a drainage reservoir whose bottom surface is close to the outer periphery of the lower cleaning roller, and the drainage collected in the drainage reservoir is sucked by the peripheral surface of the lower cleaning roller. 3. The latent image holding member cleaning device according to claim 2, wherein 4. The latent image holding member cleaning apparatus according to claim 2, wherein the lower cleaning roller is supported on the frame so that the position of the lower cleaning roller can be adjusted in a perspective direction with respect to the latent image holding member.

Images