JPH03170990A - Cleaning device - Google Patents

Abstract

PURPOSE:To obtain a stable cleaning performance by moving the tip of a blade in the tangential direction of a photosensitive drum and setting it in parallel to a rotation axis of the photosensitive drum. CONSTITUTION:By loosening a screw 52, moving upward and downward a detaining member 51 for supporting a shaft rod 34a of a supporting part, and tightening the screw 52 again, the shaft rod 34a is stopped at a desired position of a slot 50. By following a movement of this shaft rod 34a, the tip of the shaft rod 34a side of the blade 35 moves in the roughly tangential direction Y of a contact with a photosensitive drum 20. On the other hand, the movement in the radial direction X of the photosensitive drum 20 can be adjusted automatically since a blade holder is rotatable centering around a pin. In such a way, the tip of the blade 35 and a rotation axis of the photosensitive drum 20 can be set in parallel, and a stable cleaning performance is obtained.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is a cleaning device, particularly an image forming apparatus that forms an image using a rotating photoreceptor drum, for cleaning toner on the photoreceptor drum. Regarding cleaning equipment for [Prior Art] Image forming devices, such as copying machines and laser printers, generally form an electrostatic latent image on a rotating photoreceptor drum, develop the latent image with toner, and transfer the resulting toner image. It is designed to be transferred onto paper. The toner remaining on the photoreceptor drum L after the transfer process is removed by a cleaning device.

A conventional cleaning device includes, for example, a support portion having a rotation center parallel to the center of the photoreceptor drum, and a blade whose base portion is rotatably supported by the support portion and protrudes toward the photoreceptor drum side. something is known. In such a cleaning device, the blade is connected to the ζ support portion by a single screw located at the center of the blade. Therefore, the blade rotates around that screw.
By moving in the radial direction of the photoreceptor drum, the blade is aligned with respect to the photoreceptor drum. [Problems to be Solved by the Invention] In the conventional cleaning device, the dimensional accuracy of the members (such as the side plates of the housing) that support the blade is poor, and a gap is likely to occur between the tip of the blade and the photoreceptor drum. Such problems are particularly likely to occur in image forming apparatuses in which the diameter of the photoreceptor drum is small, such as personal copiers. If a gap occurs between the blade and the photoreceptor drum, uneven toner cleaning will occur, making it impossible to achieve stable toner cleaning. An object of the present invention is to provide a cleaning device that can easily bring the tip of a blade into close contact with a photoreceptor drum and achieve stable cleaning performance. [Means for Solving the Problems] Cleaning of the present invention This device is used in an image forming apparatus that forms an image using a rotating photoreceptor drum, and is used to clean toner on the photoreceptor drum.This cleaning device cleans the toner on the photoreceptor drum. The photoreceptor includes a blade that presses against the photoreceptor drum, and a blade adjusting means for moving the tip of the blade in a tangential direction of the photoreceptor drum to set it parallel to the rotation axis of the photoreceptor drum.

Note that the term "tangential direction" as used in the present invention is a concept that includes not only a strictly tangential direction but also a direction that is considered to be substantially tangential compared to the radial direction.

[Effect]

In the cleaning device of the present invention, toner on the photosensitive drum is removed by a blade.

The tip of the blade is moved in a tangential direction of the photoreceptor drum by the blade adjustment means, and is set parallel to the rotation axis of the photoreceptor drum. This allows the blade and the photoreceptor drum to contact each other in an optimal state, making it possible to achieve stable cleaning performance. [Embodiment] FIG. 3 shows an example of a copying machine employing an embodiment of the present invention.

In FIG. 3, the upper surface of the copying machine main body 11 has an original platen l.
2 is fixed, and a document holder 13 is placed on the document table I2.
are arranged so that they can be opened and closed freely. Paper feed cassettes I-14 and I5 are removably installed on the right side of the copying machine main body 11 in the figure. A paper tray 18 is installed on the left side of the copying machine main body 11 in the figure, from which copied sheets are ejected.

Inside the copying machine main body 11, an exposure device 19 for reading originals is provided at the top. This exposure device 19 is composed of a light source, a clearer, and the like. Also,
A photosensitive drum 20 on which an electrostatic latent image is formed is arranged in the center of the copying machine main body 11. Around the photoreceptor drum 20, there are a main current device 2l that charges the photoreceptor drum 20 to a predetermined charge, a developing device 22 that develops an electrostatic latent image, a transfer device 23 that transfers a toner image onto paper, and a photoreceptor. (A paper separating device 24 for separating paper from the column 20 and a cleaning device 25 for removing residual toner from the photosensitive drum 201 are arranged.
A paper feed conveyance path 27 and a paper discharge conveyance path 28 for conveying paper are provided between the image forming section 15 and the image forming section constituted by the photoreceptor drum 20 and the like, and on the downstream side of both image forming sections, respectively. There is. A fixing device 'J1.30 for fixing the transferred image on the conveyed paper is arranged between the paper discharge conveyance path 28 and the paper discharge tray 18.

The cleaning device 25 includes a cleaner 31 for removing toner from the photoreceptor drum 201, a screw conveyor 32 for discharging toner removed by the cleaner 31, and a casing for storing them. It has 33. Figure 2 shows details of the cleaner 3l. In the figure,
The cleaner 3l has a support part 34 and a blade 35 attached to the soil.
and an arm 36.

The support portion 34 is a prismatic member extending parallel to the rotation axis of the photoreceptor drum 20, and has shaft rods 34a at both ends. The support portion 34 is rotatably attached to the casing 33 (FIG. 3) by a shaft 34a. As shown in FIG. 1, the casing 33 has an elongated hole 50 for supporting the front side tent 'ζ and the support rod 34a. The elongated hole 50 is shaped like an arc concentric with the photoreceptor drum 20 . , Also, near the long hole 50, there is a screw 5.
A U-shaped locking member 51 is mounted to the casing 33 so as to be rotatable about 2 . This locking member 5l supports the pivot 34a passing through the elongated hole 50, and can be rotated by loosening the screw 52. Therefore, loosen the screw 52 and rotate the locking member 5l,
By tightening the screw 52 again, the shaft rod 34a can be locked at a desired position in the elongated hole 50. The blade 35 protrudes from the support portion 34 toward the photosensitive drum 20 side. The blade 35 is made of a flexible material such as urethane rubber. The blade 35 is
It is attached to the bottom of the blade holder 3rd. The blade holder 38 is a generally L-shaped member, and is rotatably attached to the support member 39 by a pin 40. The bin 40 is disposed at the center of the blade 35 in the longitudinal direction, and the tip of the blade 35 can move approximately in the radial direction of the photosensitive drum 20 by rotating around the pin 40 . The support member 39 is fixed to the lower right surface of the support portion 34 in the figure. One end of the arm 36 is fixed to the upper left surface of the support portion 34 in the figure. The arm 36 is bent and extends substantially horizontally to the left in the figure. A weight 4l is attached to the lower surface of the arm 36.

A solenoid 42 is arranged on the left side of the cleaner 3l in the figure. The solenoid 42 has an operating piece 43 that projects downward. This actuating piece 43 has a pin 43a that protrudes toward the back of the figure. An operating arm 44 is arranged between the solenoid 42 and the tip of the arm 36. This working arm 44 is attached so as to be rotatable about a fulcrum 45. A fulcrum 45 is at one end of the working arm 44!
! 1 is formed, and the pin 4Sa of the actuating piece 43 is fitted into this groove 46. Thereby, the operating piece 43 and the operating arm 44 are connected. The working arm 44 is such that the tip of the cleaner 31 is located below the arm 36. Also, the arm 36 of the working arm 44
One end of a spring 47 is attached to the side portion. The other end of this spring 47 is fixed to the upper part of the casing 33. As a result, the working arm 44 is always biased counterclockwise. Below the blade 35 is a cover 48 for preventing toner scattering.
is placed. This scattering prevention cover 48 is in contact with the photosensitive drum 20. Next, the effects of the above embodiment will be explained. In the copying machine main body 1, an image read by an exposure device 19 is formed as an electrostatic latent image on a photosensitive drum 20. This electrostatic latent image is developed by a developing device 22 to become a toner image. On the other hand, paper is conveyed to the photosensitive drum 20 via the paper feed conveyance path 27 from one of the paper feed cassettes I-14 and 15. The toner image on the photoreceptor drum 20 is transferred by the transfer device 23 onto the paper conveyed to the photoreceptor drum 20 . The paper onto which the toner image has been transferred is separated from the photosensitive drum 20 by a paper separation device 124 and conveyed to the fixing device 30 via the discharge conveyance path 28, where the toner image is fixed.
The paper on which the image has been fixed is discharged from the fixing device 30 to the paper discharge tray 18. As a result, it is possible to obtain a sheet of paper with a predetermined image formatted. After the toner image is transferred by the transfer device 23, the toner remaining on the electrostatic latent image on the photoreceptor drum 20 moves to the cleaning device 25 as the photoreceptor drum 200 rotates, and is removed there. Next, the toner removal operation by the cleaning device 25 will be explained. During normal copy operation, the solenoid 42
is in the on state. In this state, as shown in FIG.
The first end is curved so that it does not come into contact with the lower surface of the arm 36. As a result, the blade 35 is pressed against the photosensitive drum 20 by the weight 41. Therefore, the toner adhering to the photosensitive drum 20 is wiped off by the blade 35. The wiped toner falls onto the screw conveyor 32 due to its own weight and is discharged to the outside as waste toner. When the copying operation stops, the solenoid 42 is turned off. As a result, the operating arm 44 is rotated counterclockwise by the biasing force of the spring 47 and presses the arm 3G upward. As a result, the support portion 34 rotates clockwise, and the blade 35 separates from the photoreceptor drum 20. This separation of the blade 35 prevents deformation of the blade and deterioration of the photoreceptor.

The toner removal operation by the blade 35 as described above is performed by moving the tip of the blade 35 in the radial direction and tangential direction of the photoreceptor drum 200. Here, first, the screw 52 is loosened, the locking member 51 that supports the shaft 34a of the support part 34 is moved up and down, and the screw 52 is tightened again to stop the shaft 34a at a desired position in the elongated hole 50. ．． With this movement of the shaft 34a, the blade 3
5 on the shaft rod 34a side moves approximately in the tangential direction of the point of contact with the photoreceptor drum 20 (Y direction in FIG. I). on the other hand,
The movement of the photosensitive drum 20 in the radial direction (X direction in FIG. 1) can be automatically adjusted because the blade holder 38 is rotatable around the bin 40. Thereby, the tip of the blade 35 and the rotation axis of the photosensitive drum 20 can be set parallel to each other. As a result, the cleaner 3 of this example
1, it is possible to achieve stable cleaning performance. [Other Examples] (a) In the above-mentioned example, the pin 40 and the locking member 51 were adjusted with the blade 35 attached to the cleaner 31, but instead of the blade 35, a plate made of metal or the like could be used. You may also use it to make adjustments and then set the blade. Note that during adjustment using the metal plate, if a jig of the same shape is used instead of the photoreceptor drum 20, the photoreceptor drum 20 will not be damaged. (b) A cleaner 60 according to another embodiment is shown in FIGS. 4A, 4B, and 4C. In the figure, the blade 6l protrudes from a base 64 fixed to the casing of the cleaning device toward the photosensitive drum 20 via a blade holder 62 and an adjustment plate 63. The blade 61 is attached to one end of a dogleg-shaped blade holder 62. The blade holder 62 is movably attached to the adjustment plate 63 using a bin 65. fi adjustment fi. 63
is attached to the base 64 with screws 8. Three screws A are attached to the adjusting plate 63 at equal intervals in a direction parallel to the rotation axis of the photosensitive drum (FIG. 4A). The main body of the screw A passes through a through hole 63a provided in the adjustment plate 63, and the lower part of the screw A passes through a screw hole 64 in the base 64.
The adjusting plate 63 and the base 64 are connected by screwing into the base 64. A screw B is attached between each screw A. The screw B is screwed into a screw hole 63b provided in the adjustment plate 63, as shown in FIG. 4C, and its lower end is in contact with the upper surface of the base 64. In such a cleaner 60, adjustment Fi. 63 can be moved up and down, and can also be tilted up and down. By adjusting screw A or screw B in this way, blade 61 moves in the direction of arrow Z in FIG. 4B, that is, in the tangential direction of photosensitive drum 20. For example, by adjusting only the screws A and B on the right side of FIG. 4A, it is possible to move only the right side portion of the blade 6l in the tangential direction. This allows the tip of the blade 61 to be set parallel to the rotation axis of the photoreceptor drum. In this embodiment, the tip of the blade 61 is moved in the radial direction of the photosensitive drum by rotating the blade holder 62 about the bin 65. (C) FIG. 5 shows a cleaner To according to yet another embodiment. In the figure, the cleaner 70 includes a support portion 71 and a blade 73 that protrudes from the support portion 71 through a blade holder 72 toward the photosensitive drum. The support portion 71 includes a rectangular slope portion 71a, vertical wall portions 7lb provided at both longitudinal ends of the slope portion 71a, and the vertical wall portion 7l.
and shaft rods 71c protruding outward from the respective portions b. The support portion 71 includes a shaft rod 71c. 7
1C is rotatably attached to the casing of the cleaning device. The blade holder 72 has a support part 7
It is attached to the lower surface of the slope portion 71a so as to protrude from 1 toward the photoreceptor drum side. The plate portion 71a and the blade holder 72 are connected by screws A arranged at equal intervals in the longitudinal direction. Further, between each screw A, a screw B is attached. These screws A and B are respectively the screw A used in the other example (a) above.
and screw B, so that the distance between the slope portion 71a and the blade holder 72 can be adjusted. Note that the blade 73 is attached to protrude from the blade holder 72 toward the photosensitive drum. In such an embodiment, the blade 73 can be adjusted by adjusting each screw A and screw B as in the other embodiments described above.
can be moved in the direction of arrow Z in Figure 5 (tangential direction of the photoreceptor drum). This allows the tip of the blade 73 to be set parallel to the rotation axis of the photoreceptor drum. [Effects of the Invention] According to the present invention, the tip of the blade can be moved in the tangential direction of the photoreceptor drum and set parallel to the rotation axis of the photoreceptor drum. Therefore, the cleaning device of the present invention can achieve stable cleaning performance.

[Brief explanation of the drawing]

FIG. 1 is a schematic partial diagram of an embodiment of the present invention, FIG. 2 is a schematic diagram of a cleaner used in the embodiment, FIG. 3 is a vertical sectional view of a copying machine in which the embodiment is adopted, and FIG. The figure is a plan view of another embodiment, and Figure 4B is rVB-IVB of Figure 4A.
A sectional view, FIG. 4C is an IVC-TVC sectional view of FIG. 4A,
FIG. 5 is a schematic perspective view of yet another embodiment. 20... Photosensitive drum, 34, 61. 73... Blade, 50... Long hole, 51... Locking member, A, B.
··Screw.

Claims (1)

[Claims] (1) In an image forming apparatus that forms images using a rotating photoreceptor drum, a cleaning device for cleaning toner on the photoreceptor drum, the blade being in pressure contact with the surface of the photoreceptor drum; A cleaning device comprising: blade adjustment means for moving the tip of the blade in a tangential direction of the photoreceptor drum to set it parallel to the rotation axis of the photoreceptor drum.