JPS5940679A - Cleaning device of electrostatic copying machine - Google Patents

Abstract

PURPOSE:To prevent a lump of toner and paper powder from reaching a development chamber by sliding a cleaning member and a fur brush on a photoreceptor, and stopping only toner with the cleaning member, and guiding the residual toner into the development chamber when the cleaning member is separated from the photoreceptor. CONSTITUTION:When an oscillation lever 62 is turned through a clutch 84, gears 85 and 83, and a revolving shaft 82 during picture formation to bring the cleaning member into slide contact with the photoreceptor, the fur brush also comes into slide contact with the photoreceptor 28. A lump of toner and paper powder is stopped with the fur brush 81 and does not reach the cleaning member 61, and the cleaning member 61 stops only the residual toner. When the picture formation is completed, the cleaning member 61 leaves the photoreceptor 28 and the residual toner is guided to a developing device. Therefore, the lump of the toner and paper powder is removed easily and does not reach the developing device.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cleaning device for an electrostatic copying machine, and more particularly, the present invention relates to a cleaning device for an electrostatic copying machine. The present invention relates to a cleaning device for an electrostatic copying machine, in which a wiping member is separated from a photoreceptor during image formation, and the blocked residual toner is brought to a developing device.

Conventionally, when paper dust is mixed into the residual toner on the photoconductor, the paper dust and the residual toner are blocked by a wiping member, resulting in the formation of a lump of paper dust and toner. Such lumps are also brought to the developing device when the wiping member separates from the photoreceptor after the copying operation is completed. On the other hand, in the developing device, in order to prevent toner from scattering, felt members are provided on both sides of the frame of the developing device to make sliding contact with the photoreceptor. In order to prevent this, a rubber blade member is provided at the upstream end of the frame in the direction in which the photoreceptor moves, and is in sliding contact with the photoreceptor. The blade member has sufficient resiliency to allow residual toner from the cleaning device to enter the developer device. However, when a lump of residual toner and paper dust is brought to the developing device as described above, the lump remains between the blade and the photoreceptor, creating a gap between the blade and the photoreceptor. arise. Therefore, the toner is blown up and scattered from the gap. Note that if the pressing force of the blade against the photoreceptor is reduced to allow the lump to enter the developing device, it becomes difficult to prevent the toner from being blown up from within the developing device.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned technical problem and provide a cleaning device that prevents agglomerates of toner and paper dust from being introduced into a developing device.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a transfer type electrostatic copying machine according to an embodiment of the present invention. The copy paper in the paper feed roller 7) 13 and 14 attached to the body 12 of the electrostatic copying machine 11 is fed by the paper feed roller 15,
16, the sheets are selectively fed one by one, and are transported by a transport device 17 having three pairs of rollers.

On the horizontal transparent plate 20 provided at the top of the fuselage 12,
A document 21 is placed thereon, and this document 21 is brought into close contact with the transparent plate 20 by a holding plate 22 . An optical device 24 is provided inside the fuselage 12 at an upper portion partitioned by a partition plate 23 . The optical device 24 includes an exposure lamp 25, a reflecting mirror 26, 27, which efficiently guides the light from the exposure lamp 25 to the original 21, and a light image of the original 21 to the photosensitive drum 18. A reflector 29 that forms an image on 28
, 30.31, a lens 32, and a reflecting mirror 33.

A cooling fan 34 for cooling the optical device 24 is provided near the left end of the body 12 in FIG.

During exposure, the optical device 24 excluding the lens 32 and the reflecting mirror 33 moves from the left to the right inside the body 12 for exposure. In this exposure movement, the moving speed of the exposure lamp 25 and the reflectors 926, 27, 29 is as follows:
It is set to twice the movement speed of 1. At the end of the exposure, the optical device 24 except the lens 32 and the reflecting mirror 33 moves in the opposite direction to the exposure movement direction and returns to the rest position shown by the solid line. Moreover, the lens 32 moves slightly along the exposure movement direction depending on the copying magnification and is then fixed. That is, during reduction copying, the lens 32 is displaced from the position shown by the solid line to the position P shown by the imaginary line. At this time, the reflecting mirrors 30, 31 are displaced to the positions indicated by imaginary lines. Conversely, during enlarged copying, the lens 32 is slightly displaced from the position shown by the solid line in the direction opposite to the position P.

The photoreceptor 28 is charged by a corona discharger 37.

A document image is formed on the charged photoreceptor 28 from the optical device 24 in the exposure area 38 through the opening 39 of the partition plate 23 and the exposure window 40, thereby forming an electrostatic latent image. This electrostatic latent image is developed into a toner image by the developing device 41. This toner image is transferred onto the copy paper conveyed by the conveyance device 17 in the transfer area 54 by the action of the corona discharger 42 . The copy paper onto which the toner image has been transferred is reliably peeled off from the photoreceptor 28 by the action of the static eliminator 43. The peeled copy paper is conveyed to a heat fixing device 47 by an endless conveyor belt 46 driven by rollers 44 and 45. The heat fixing device 47 includes a heat roller 49 having a built-in heater 48 and a pressure roller 50 that is in pressure contact with the heat roller 49.
Equipped with. When the copy paper passes between the heat roller 49 and the pressure roller 50, the toner on the copy paper is thermally melted and the original image is fixed. Copy paper that has been fixed is
The paper is discharged onto a tray 52 by a pair of paper discharge rollers 51 .

The photoreceptor 28 after the transfer process is cleaned by a cleaning device 9 according to the present invention. Note that a charge eliminating lamp 53 is provided between the cleaning device 9 and the charging corona discharger 37 to remove residual charges on the photoreceptor. Further, a charge eliminating lamp 96 is provided between the collapsing discharger 37 and the exposure area 38 for removing the charge on the excess area of the photoreceptor 28 during reduction copying.

FIG. 2 is a sectional view showing the cleaning device 9, the developing device 41, and the photosensitive drum 18 in detail.

The frame body 55 of the developing device 41 is connected to the photoconductor 2 of the photoconductor drum 1B.
It is arranged with an opening facing 8, and in the opening,
A developing roller 5 having a permanent magnet 56 built into a cylindrical body 57
8 is arranged close to the photoreceptor 28 and having an axis parallel to the photoreceptor drum 18 .

Further, a two-component developer storage section 59 is formed within the frame 55, and the two-component developer stored in this storage section 59 is moved to the position of the developing roller 58 while being stirred by the stirring means 97. brought about.

A magnetic brush 98 is formed by the developer on the outer peripheral surface of the developing roller 58, and this magnetic brush 9B is indicated by an arrow 99.
The photoreceptor 28 is rubbed by rotating in the direction indicated by . As a result, the electrostatic latent image on the photoreceptor 28 is visualized.

A felt member 100 that comes into sliding contact with the photoreceptor 28 is fixedly provided on the periphery of both measuring portions of the opening of the frame 55 facing the photoreceptor 28 . This felt member 100 prevents the toner inside the frame 55 from scattering outward. moreover,
A rubber blade member 101 is provided at the upstream end of the frame 55 along the moving direction of the photosensitive drum 18, that is, at the upper end edge of the opening, and is in contact with the photosensitive member 28. This blade member 101 prevents toner blown up as the developing roller 58 rotates from scattering above the frame 55 .

A toner replenishing device B 102 is provided at the top of the frame 55, and toner is replenished from the toner replenishing device 102 to the storage portion 59 in response to consumption of toner in the developing device 41.

Note that the configurations of the developing device 41 and the toner replenishing device 102 as described above are conventionally known.

The cleaning device 9 according to the present invention is arranged between the transfer area 54 and the charging corona discharger 37 along the moving direction of the photosensitive drum 18. A wiping member 61 is provided in the casing 60 of the cleaning device 9 at a position above the photosensitive drum 18 and close to the corona discharger 37 along the direction of movement of the photosensitive drum 18, and is movable toward and away from the photosensitive body 28. is supported. This wiping member 61 is
It is fixedly provided at one end of a swing lever 62 that extends in a horizontal direction substantially perpendicular to the axis of the photosensitive drum 18 . The other end of the swing lever 62 passes through a long hole 64 formed in the rear plate 63 of the casing 60 and extending vertically. Moreover, the swing lever 62 is rotatably supported in the middle by a pivot shaft 65 parallel to the axis of the photosensitive drum 18 .

3 is a perspective view of the cleaning device 9 seen from behind, FIG. 4 is a cutaway perspective view of the cleaning device 9 seen from the opposite direction to FIG. 3, and FIG. 5 is a perspective view of the cleaning device 9. It is a diagram of the central part seen from behind. Casing 6
The ends of the side plates 66 and 67 on the side away from the photosensitive drum 18 are pivotally supported by a support shaft 68 parallel to the photosensitive drum 18, and both ends of this support shaft 68 are connected to the body 1.
2 (see No. 1171) on both side plates 69,70. Also, on both side plates 66 and 67, the photosensitive drum 1
A shaft 71 having an axis parallel to the photosensitive drum 18 is inserted into the end near the photosensitive drum 18, and both ends of the shaft 71 are cut out to open upward at the upper part of the side plates 69 and 70 of the body 120. Received by recesses 72,73. Therefore, the casing 6° can be rotated upwardly around the support shaft 68.

A solenoid 74 having an axis extending parallel to the photosensitive drum 18 is supported on the rear plate 63 of the casing 60, and one end of a spring 76 is connected to a plunger 75 that is driven to expand and contract by the solenoid 74. The other end of the spring 76 is connected to the lower end of the cam 78. This cam 78 is
Below the other end of the m'tthv par 62 protruding from the rear plate 63, it is rotatably supported on the rear plate 63 by a pin 79 having an axis perpendicular to the axis of the solenoid 74.

A cam surface 8o is formed on the upper edge of the cam 78, and the other end of the swing lever 62 always comes into contact with this cam surface 8o.

In FIG. 5, the plunger 75° cam 78 is shown as a solid line.
The position of the swing lever 62 indicates the time of non-image formation. The swing lever 62 is connected to a pivot shaft 65 as shown by the imaginary line in FIG.
The wiping member 61 is rotated counterclockwise around the wiping member 61, and thus the wiping member 61 is separated from the photoreceptor 28. When forming an image in this state, the solenoid 74 is excited, and the plunger 75 is thereby drawn into the solenoid 74. In response to this contraction of the plunger 75, the cam 78 is rotated clockwise around the pin 79 as shown by the imaginary line in FIG. 5, and the other end of the swing lever 62 is pushed upward. As a result, the swing lever 62 rotates clockwise in FIG. When the image forming operation is completed, the solenoid 74 is demagnetized, and the plunger 75 and cam 78 return to the positions indicated by solid lines in FIG. 5 accordingly. The other end of the swinging lever 62 is biased downward by a plate spring 105 fixed to the rear plate 63 of the casing 60, and swings following the rotational movement of the cam 78. The lever 62 returns to the position shown in phantom in FIG.

Referring again to FIG. 2, on the upstream side of the wiping member 61 along the moving direction of the photosensitive drum 18, the casing 6
A fur brush 81 having an axis parallel to the photosensitive drum 18 and in sliding contact with the photosensitive member 28 is supported on the fur brush 81 . The rotary shaft 82 of the fur brush 81 is rotatably supported by both side plates 66 and 67 of the casing 60, and a gear 83 is provided at the end of the rotary shaft 82 protruding from the side plates 67 as shown in FIG. is fixedly provided. On the other hand, a gear 85 is attached to the end of the rotating shaft 65 protruding from the side plate 67 via a one-way clutch 84, and this gear 85 meshes with the gear 83.

FIG. 7 is a simplified cross-sectional view for explaining the mechanism of the one-way clutch 84. This one-way clutch 84 transmits only the rotational power in the direction of arrow 86 from the rotation shaft 65 to the gear 85. That is, in the inner peripheral surface of the support body 87 fixed to the gear 85, recesses 88 having inner peripheral surfaces facing the arrow 86 direction and close to the rotation shaft 65 are formed at intervals in the circumferential direction. Ru. A cylindrical roller 89 is provided between each recess 88 and the outer peripheral surface of the rotation shaft 65, and each roller 89 has a spring 90.
It is elastically biased in the direction of arrow 86.

When the rotation shaft 65 rotates in the direction of arrow 86, the rollers 89 are caught between the recess 88 and the rotation shaft 65, as shown in FIG. 7(a). As a result, the rotational power of the rotation shaft 65 is transferred to the roller 89.
The signal is transmitted to the support body 87 and the gear 85 via.

When the rotation shaft 65 rotates in the direction indicated by the arrow 91 opposite to the arrow 86, the roller 89 is rotated by the spring 9 as shown in FIG. 7(b).
It is displaced in the direction of arrow 91 against the spring force of 0. As a result, the rotational power of the rotation shaft 65 is not transmitted to the support body 87 and the gear 85.

In this way, the one-way clutch 84 transmits only the rotational power of the rotation shaft 65 in the direction of the arrow 86 to the gear 85.
5 to the rotating shaft 82 via the gear 83. Moreover, the rotation direction indicated by the arrow 86 is selected as the rotation direction when the swing lever 62 rotates clockwise in FIG. 2 to bring the wiping member 61 into sliding contact with the photoreceptor 28. Therefore, the fur brush 81 rotates in the direction shown by arrow 92 in FIG. 2 as the wiping member 61 comes into sliding contact with the photoreceptor during image formation. Furthermore, the angular displacement meter based on a single rotational movement of the fur brush 81 is set in advance to the extent that it will change 360 degrees after 1000 rotational movements, for example, and the gear 83. The shape of is determined.

Referring again to FIG. 2, a scraping plate 93 is provided at the lower part of the casing 60, facing the photoreceptor 28 of the photosensitive drum 18 and extending upward. contacts the fur brush 81. Further, a storage portion 94 is formed between the scraping plate 93 and the rear plate 63. Further, a permanent magnet piece 95 is fixed to the surface of the scraping plate 93 facing the photoreceptor 28.

In the cleaning device 9 configured in this manner, the fur brush 81 blocks the lumps of paper dust and toner adhering to the photoreceptor 28 during image formation. Therefore, lumps of paper powder and toner are not brought to the wiping member 61, and the wiping member 6
1, only residual toner is blocked. Note that if carrier is attached to the photoreceptor 28, the attached carrier is removed by the permanent magnet piece 95.

When image formation is completed, the wiping member 61 is separated from the photoreceptor 28 as described above, and the remaining toner that has been blocked is transferred to the developing device 41 as the photoreceptor 28 moves. brought about. At this time, the lumps consisting of toner and paper powder are blocked by the fur brush 81, so that they are not brought to the developing device 41, and therefore the lumps are not brought to the blade member 10 of the developing device 41 as in the conventional case.
1 and the photoreceptor 28 is reliably prevented,
As a result, the occurrence of the toner blow-up phenomenon in the developing device 41 is prevented.

During the next image formation, when the wiping member 61 moves close to the photoreceptor 28, the fur brush 81 moves in the direction of the arrow 92 (
(see Figure 2). Accordingly, the lump consisting of toner and paper powder adhering to the fur brush 81 at the position of the scraping plate 93 is scraped off by the scraping plate 93 and brought to the storage section 94.

Therefore, the contact portion of the fur brush 81 with the photoreceptor 28 is a clean portion free from the above-mentioned lumps. In addition, along with the scraping operation by the scraping plate 93, the fur brush 81 is rotated slowly so that the toner and paper powder do not scatter within the casing 60.

The toner and paper powder stored in the storage section 94 may be removed by opening the casing 60 around the support shaft 68 during maintenance.

In another embodiment of the invention, fur brush 81 may be rotated in the opposite direction to arrow 92 in FIG.

Moreover, the permanent magnet piece 95 may be omitted. Furthermore, although the above embodiments have been described in connection with an electrostatic copying machine that uses a two-component developer, the present invention may also be implemented in connection with an electrostatic copying machine that uses a one-component developer. can.

As described above, according to the present invention, the lumps of toner and paper dust are blocked by the fur brush, so that they are not introduced into the developing device, so that the lumps are not present between the blade and the photoreceptor in the developing device. Words that bite in forcefully,
Blowing up of toner due to the biting is reliably prevented. Moreover, since the fur brush rotates by a set angle as the wiping member approaches the photoconductor, the fur brush does not have a lump of toner and paper dust attached to the leaves. The lumps can be easily removed.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a transfer type electrostatic copying machine according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing details of a cleaning device 9, a developing device 41, and a photosensitive drum 18, and FIG. 3 is a cleaning FIG. 4 is a perspective view of the cleaning device 9 seen from behind, FIG. 4 is a cutaway perspective view of the cleaning device 9 taken from the opposite direction to FIG. 3, and FIG. FIG. 6 is a sectional view showing the connected state of the rotating shaft 65 and the rotating shaft 82, and FIG. 7 is a simplified sectional view for explaining the function of the one-way clutch 84. 9...Cleaning device, 18...Photosensitive drum, 2
8... Photoreceptor, 37... Corona discharger, 41...
Developing device, 61... Wiping member, 62... Rocking lever, 65... Rotating shaft, 74... Renoid, 78...
・Cam, 81... Fur brush, 82... Rotating shaft,
84... One-way clutch agent Patent attorney Kei Nishi Part 6 Figure 7

Claims (1)

[Claims] +11 A wiping member disposed upstream of a charging corona discharger along the moving direction of the photoreceptor is brought into sliding contact with the photoreceptor during image formation to remove residual toner on the photoreceptor. In the cleaning device for an electrostatic copying machine, the cleaning device for an electrostatic copying machine is configured to block the photoconductor and move the wiping member away from the photoconductor during non-image formation to bring the blocked residual toner to a developing device. A fur brush that is further upstream of the wiping member along the direction and slidingly contacts the photoconductor on the downstream side of the transfer area, and a fur brush that is in sliding contact with the photoconductor at a position further upstream of the wiping member and downstream of the transfer area; A cleaning device for an electrostatic copying machine, comprising means for angularly displacing the fur brush by a predetermined angle. (2) The wiping member is provided at one end of the swinging lever, and the rotating shaft that pivotally supports the swinging lever is connected to the rotating shaft of the fur brush via a one-sided clutch. A cleaning device for an electrostatic copying machine according to claim 1.