JP2010224394A - Cleaning device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning device for a rotating body such as a photoreceptor, an intermediate transfer body or a secondary transfer member to which toner and releasing oil adhere, capable of always appropriately applying lubricant to a surface of the rotating body, and to provide an image forming apparatus including the same. <P>SOLUTION: Before mixture is stuck to solid lubricant 7 by the releasing oil and the toner, for example, after finishing printing operation, a secondary transfer roller 22 and a first brush roller 5 are driven to rotate in such a state that the secondary transfer roller 22 and an intermediate transfer belt 10 are separated from each other, to scrape off the releasing oil and the toner adhering to the solid lubricant 7 from a surface of the solid lubricant 7 by the first brush roller 5 and make them adhere to an outer circumferential surface 22a of the secondary transfer roller 22, and then collect them by a cleaning blade means 4 and a second brush roller 9. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cleaning device used in an electrophotographic image forming apparatus such as a copying machine or a printer, and an image forming apparatus including the same.

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus such as a copying machine or a printer, each color toner image on a photosensitive member is primarily transferred onto an intermediate transfer member such as an intermediate transfer belt for each color, and is superimposed and transferred. 2. Description of the Related Art Image forming apparatuses that form a color image by batch secondary transfer from a body onto a recording medium are widely known (see, for example, Patent Document 1). In this case, the toner remaining on the intermediate transfer member after the secondary transfer of the toner image onto the recording medium is removed and cleaned from the surface of the intermediate transfer member by an intermediate transfer member cleaning device such as a cleaning blade or a brush roller. Thus, the toner image transferred to the intermediate transfer member is not adversely affected.
In addition, with the recent improvement in image quality, toner particles have become smaller and spherical with polymerized toner. With the improvement of this toner, the intermediate transfer member considering the above-mentioned cleaning properties also maintains its cleaning properties over time. It's getting harder to do. That is, when the residual toner is repeatedly removed from the surface of the intermediate transfer member with the cleaning blade, the surface friction coefficient of the intermediate transfer member increases, and the leading edge of the cleaning blade is caught in the transfer direction of the intermediate transfer member as the surface friction coefficient increases. It becomes easy to generate | occur | produce and a cleaning defect will generate | occur | produce when a cleaning blade gets involved. As a result, residual toner adheres to the surface of the intermediate transfer member, and toner image loss (filming) is likely to occur.

In view of this, Patent Document 2 discloses that a lubricant application device that applies a lubricant to the surface of the intermediate transfer body using a brush roller and a solid lubricant is disclosed in order to reduce the surface friction coefficient of the intermediate transfer body. ing.
Further, in the indirect transfer type tandem type image forming apparatus, the secondary transfer member remains in contact with the intermediate transfer member during the continuous image forming operation in which images are continuously formed on the recording medium. Therefore, when a toner image of a process control toner density reference pattern that is not transferred to the recording medium is formed on the intermediate transfer body during the continuous image forming operation, the toner image of the reference density pattern on the intermediate transfer body is secondary. It is transferred to the transfer member side. The toner that has been transferred and adhered to the secondary transfer member causes contamination on the surface of the intermediate transfer member and on the back surface of the recording medium.
As described above, since the toner may be transferred onto the surface of the secondary transfer member, it is necessary to reliably clean the toner on the secondary transfer member. Therefore, Patent Document 3 discloses that a lubricant application device that applies a lubricant together with a cleaning blade in order to satisfactorily clean the toner on the secondary transfer member is disclosed.

By the way, a method of fixing a toner image on a recording medium with heat and pressure by passing the toner image transferred onto the recording medium through a pressure contact portion between a fixing roller and a pressure roller is widely performed. In such a fixing device, since the fixing roller comes into contact with the toner at the time of fixing, a part of the toner remains attached to the surface of the fixing roller, and the recording medium comes into contact with the recording medium conveyed next time. In some cases, the recording medium adheres to and fouls, or the recording medium adheres to the fixing roller and winds. In order to prevent such an accident, a release oil such as silicone oil is applied to the fixing roller to prevent the recording medium from being wound around the fixing roller.
When a fixing device with such a release oil applied to the surface of the fixing roller is used, when a toner image is formed on both the front and back surfaces of the recording medium, the release oil adheres to the back surface of the recording medium once passed through the fixing device. When the toner image is transferred from the intermediate transfer member to the back surface of the recording medium to which the release oil is attached, the recording medium to which the release oil is attached passes through the secondary transfer device. As a result, the release oil adheres to the secondary transfer member such as the secondary transfer roller that contacts the recording medium, the intermediate transfer member, and the photosensitive member that contacts the intermediate transfer member. As described above, when an intermediate transfer body having release oil adhered to the surface is used, an oil ghost phenomenon occurs. In order to suppress the occurrence of such an oil ghost phenomenon, it has been proposed that a cleaning blade for removing release oil adhering to the surface of the intermediate transfer member is disposed in sliding contact with the surface of the intermediate transfer member. (See Patent Document 4)

In Patent Documents 1 and 2, as a cleaning device for the intermediate transfer belt, a cleaning blade that slides on the surface of the intermediate transfer belt to remove residual toner, and a lubricant application device that reduces the surface friction coefficient of the intermediate lubricant transfer belt are disclosed. In these image forming apparatuses, there is no disclosure regarding the use of release oil in the fixing device.
Further, Patent Document 3 discloses an image forming apparatus including a cleaning device having a cleaning blade and a lubricant application device that are in sliding contact with the surface of the secondary transfer roller. In the fixing device of this image forming device, There is no disclosure about the use of release oil.
Patent Document 4 describes that a release oil is used in a fixing device of an image forming apparatus, and a cleaning blade for removing residual toner and release oil is slid on the surface of the intermediate transfer belt. It is disclosed to contact. However, this patent document 4 does not disclose providing a lubricant application device that reduces the surface friction coefficient of the intermediate transfer belt as a cleaning device.

When the release oil is used in the fixing device of the image forming apparatus, the release oil adhering to the recording medium is lubricated via a brush roller that applies a lubricant in the cleaning device for the secondary transfer roller or the intermediate transfer member. It also adheres to the agent. In addition, when a large amount of toner comes into contact with the cleaning blade of the cleaning device, such as when a jam occurs, the cleaning blade may not be able to completely remove the toner. It adheres to the lubricant via the roller.
As described above, if the release oil and the toner are left attached to the lubricant, the mixture of the release oil and the toner adheres to the surface of the lubricant and the lubricant cannot be applied. As a result, in the part where the lubricant is not applied, the toner cannot be completely removed by the cleaning blade, and the recording medium is contaminated by the slipped toner, or the surface friction coefficient is increased and the cleaning blade is turned up. Will occur.
The present invention has been made in consideration of the above circumstances, and in a cleaning device for a rotating body such as a photoreceptor, an intermediate transfer body, and a secondary transfer member to which toner and release oil are adhered, a lubricant is applied to the surface of the rotating body. It is an object of the present invention to provide a cleaning device capable of always properly applying to an image forming apparatus and an image forming apparatus including the same.

In order to solve the above problems, the invention of claim 1 is directed to a lubricant applying means for applying a lubricant to the surface of the rotating body to which the toner and the release oil adhere, and the toner and releasing agent attached to the surface of the rotating body. In the cleaning apparatus including a cleaning blade for removing mold oil from the surface of the rotating body, the lubricant applying means includes a brush roller that is in sliding contact with the surface of the rotating body, and a solid lubricant that is in pressure contact with the brush roller. And the lubricant is scraped off from the surface of the solid lubricant by the rotation of the brush roller and applied to the surface of the rotating body, and the brush roller is driven to rotate on the surface of the solid lubricant after completion of printing. Control is performed so as to perform a lubricant adhesion preventing operation for scraping off the adhering toner and release oil.
According to a second aspect of the present invention, in the cleaning device according to the first aspect, the rotating member is a photosensitive member on which a toner image is formed on the surface, and an intermediate transfer on which the toner image formed on the photosensitive member is transferred. Or a secondary transfer member that transfers a toner image on the intermediate transfer member onto a recording medium.
According to a third aspect of the present invention, in the cleaning device according to the second aspect, the rotating body is a secondary transfer member.
According to a fourth aspect of the present invention, in the cleaning device according to the third aspect, the secondary transfer member is attached to and separated from the intermediate transfer member, and the secondary transfer member is separated from the intermediate transfer member. In this case, the lubricant is prevented from being fixed.

A fifth aspect of the present invention is an image forming apparatus including the cleaning device according to any one of the first to fourth aspects.
According to a sixth aspect of the present invention, in the image forming apparatus according to the fifth aspect, the image forming apparatus reversely travels a recording medium having a toner image fixed on the front surface to form a toner image on the back surface of the recording medium. And a double-sided image forming means.
According to a seventh aspect of the present invention, in the image forming apparatus according to the sixth aspect, the lubricant sticking prevention operation is performed after the operation for forming an image on both sides of the recording medium is completed.
According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect, the rotation time of the brush roller in the lubricant sticking prevention operation is changed according to the number of sheets to be image-formed on both sides of the recording medium. It is characterized by doing.

According to a ninth aspect of the present invention, in the image forming apparatus according to any one of the fifth to eighth aspects, the lubricant sticking prevention operation is performed, and a toner density reference pattern image is formed or transferred to the rotating body. It is performed later.
According to a tenth aspect of the present invention, in the image forming apparatus according to any one of the fifth to ninth aspects, the brush roller is controlled when the image forming apparatus is started up after an abnormal stop. To do.
The invention according to claim 11 is the image forming apparatus according to any one of claims 5 to 10, wherein the cleaning device is arranged for a plurality of the rotating bodies, and the toner for the solid lubricant is provided. It is characterized in that the rotation time of the brush roller during the control of the brush roller is lengthened as the rotating body in which the release oil is easily fixed.

  According to the present invention, the lubricant application means includes a brush roller that is in sliding contact with the surface of the rotating body, and a solid lubricant that is in pressure contact with the brush roller, and the solid lubricant is rotated by the rotation of the brush roller. The lubricant and the release oil are scraped off from the surface and applied to the surface of the rotating body, and the brush roller is driven to rotate after the end of printing by the rotating body by the rotating body and adheres to the surface of the solid lubricant. In a cleaning device for a rotating body such as a photoconductor, an intermediate transfer body, and a secondary transfer member to which toner and release oil are adhered, the lubricant is always properly applied to the surface of the rotating body. It is possible to provide a cleaning device capable of performing the above and an image forming apparatus including the same.

1 is a schematic diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating a schematic configuration of one image forming unit used in the image forming apparatus illustrated in FIG. 1. 1 is an enlarged configuration diagram illustrating a fixing device used in an image forming apparatus according to an embodiment of the present invention. 1 is a diagram illustrating a schematic configuration of a secondary transfer roller cleaning device according to an embodiment of the present invention. FIG. 2 is a block diagram of a control device for a cleaning device used in the image forming apparatus shown in FIG. 1. It is a figure which shows schematic structure of the belt cleaning apparatus which concerns on one Embodiment by this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing a schematic configuration of one image forming unit used in the image forming apparatus shown in FIG.
As shown in FIG. 1, the image forming apparatus according to the present embodiment forms yellow (Y), magenta (M), cyan (C), and black (K) (hereinafter abbreviated as YMCK) toner images. Indirect (intermediate) transfer having image forming units 20 arranged in series along the transfer direction (arrow A) of the endless intermediate transfer belt 10 in which the image forming units 18Y, 18M, 18C, and 18K are intermediate transfer members. This is a tandem type image forming apparatus. The image forming apparatus includes a conveyance path 48, a manual sheet feeding path 53, a manual tray 51, a registration roller pair 49, a conveyance belt unit 24, a fixing device 25, a conveyance switching device 29, a discharge roller pair 52, a discharge tray 57, A paper feed cassette 44, a switchback path 55, and the like are provided. Further, above the image forming units 18Y, 18M, 18C, and 18K, Y image, M image, C image, and K image based on image information read by an external scanner and image information sent from a personal computer. The optical writing unit 21 irradiates the photoconductors 40Y, 40M, 40C, and 40K of the image forming units 18Y, 18M, 18C, and 18K with the light beams LY, LM, LC, and LK that form the electrostatic latent image of .

Each of the image forming units 18Y, 18M, 18C, and 18K includes a charging device, a developing device, and a cleaning device around the drum-shaped photoconductors 40Y, 40M, 40C, and 40K that rotate in the directions of the arrows. These image forming units 18Y, 18M, 18C, and 18K basically have the same configuration except that the toner used is different. Therefore, one image forming unit 18 will be described with reference to FIG. As shown in FIG. 2, the image forming unit 18 includes a charging device 90, a developing device 60, and a photoconductor cleaning device for uniformly charging the surface of the photoconductor 40 around the drum-like photoconductor 40 rotating in the direction of the arrow. The charging device 90, the developing device 60, and the photosensitive member cleaning device 30 are integrally connected to the photosensitive member 40 and constitute a process cartridge that is detachably attached to the image forming apparatus. is doing.
The developing device 60 irradiates the photoconductor 40 from the optical writing unit 21 (see FIG. 1) using a two-component developer (hereinafter simply referred to as developer) containing a magnetic carrier (not shown) and non-magnetic Y toner. The toner is supplied to the electrostatic latent image formed by the light beam L and developed into a toner image. The developing device 60 includes developing rollers 61A and 61B that have a built-in fixed magnet, perform the panning while holding the developer with a rotating sleeve, and supply toner to the electrostatic latent image on the photoreceptor 40. . Instead of the two-component developer, a type in which development is performed with a one-component developer not containing a magnetic carrier may be used.

  The photoconductor cleaning device 30 includes a polyurethane rubber cleaning blade 31 and a cleaning brush roller 32 for removing paper dust, the tip of which is disposed in sliding contact with the surface of the photoconductor 40. The toner remaining on the surface of the photoconductor 40 after the toner image on the photoconductor 40 is transferred to the intermediate transfer belt 10 is removed from the surface of the photoconductor 40 by the cleaning brush roller 32 and the cleaning blade 31. ing. Further, on the downstream side of the rotation direction (arrow B direction) of the photoconductor 40, a brush roller 33 that slides in contact with the surface of the photoconductor 40 and is driven to rotate in the direction of arrow C, and a spring member 37 with respect to the brush roller 33. And a solid lubricant 34 that is in pressure contact. Then, the solid lubricant 34 is scraped off by the rotation of the brush roller 33, and the lubricant applying means 35 is configured to apply the scraped lubricant onto the surface of the photoreceptor 40. A lubricant is applied to the surface of the photoconductor 40 by the lubricant application means 35 to reduce the surface friction coefficient of the photoconductor 40, thereby facilitating transfer of the toner image, and using the cleaning brush roller 32 and the cleaning blade 31. It is possible to easily remove the residual toner. The residual toner removed in this manner is collected by a toner collecting unit (not shown) by the conveying screw 36.

As shown in FIG. 1, the four image forming units 18Y, 18M, 18C, and 18K are stretched by support rollers 14, 15, 16 and a guide roller 13, and the support rollers 14, 15, 16 An endless intermediate transfer belt 10 that is an intermediate transfer member that is transported in the direction of arrow A by rotation of one support roller is provided. Primary transfer rollers 62Y, 62M, 62C, and 62K are disposed at positions facing the image forming units 18Y, 18M, 18C, and 18K via the intermediate transfer belt 10. These primary transfer rollers 62Y, 62M, 62C, and 62K apply a primary transfer bias to stack toner images formed on the photoreceptors 40Y, 40M, 40C, and 40K on the surface of the intermediate transfer belt 10. The toner image is transferred to form a four-color toner image (color image) on the intermediate transfer belt 10.
Further, as shown in FIG. 1, after the toner image transferred from the photoconductors 40Y, 40M, 40C, and 40K is transferred onto the intermediate transfer belt 10 onto the recording medium P such as transfer paper by the secondary transfer roller 22. A belt cleaning device 17 for removing the remaining toner is provided. The belt cleaning device 17 will be described later.

As shown in FIG. 1, a registration roller pair 49 is disposed on the right side of the secondary transfer roller 22 in the drawing, and the recording medium P sandwiched between the rollers is a four-color toner image on the intermediate transfer belt 10. Are sent to the secondary transfer nip between the secondary transfer roller 22 and the support roller 16 as the secondary transfer counter roller at a timing that can be synchronized with each other. In the secondary transfer nip, the four-color toner images on the intermediate transfer belt 10 are collectively transferred to the recording medium P due to the influence of the secondary transfer electric field and the nip pressure, and become a full-color image combined with the white color of the recording medium P.
The recording medium P that has passed through the secondary transfer nip is separated from the intermediate transfer belt 10 and transferred to the transport belt unit 24. The transport belt unit 24 moves the endless transport belt 24a endlessly in the counterclockwise direction in the figure by the rotational drive of the drive roller 23A while being stretched by the drive roller 23A and the driven roller 23B. The recording medium P delivered from the secondary transfer nip is conveyed along with the endless movement of the belt while being held on the belt upper tension surface, and delivered to the fixing device 25.

FIG. 3 is an enlarged configuration diagram showing the fixing device used in the image forming apparatus according to the embodiment of the present invention. The fixing device 25 includes a pressure roller 27, a fixing belt 26, an elastic drive roller 26a, a heating roller 26b, a toner removing unit 26c, an oil application roller 26d, an oil supply roller 26e, an oil permeating felt 26f, an oil tray 26g, and the like. is doing.
The endless fixing belt 26 is wound around an elastic drive roller 26a and a heating roller 26b containing a heat source such as a halogen lamp, and the elastic drive roller 26a is rotated in the clockwise direction in the drawing. Endlessly moves clockwise in the figure. Then, it is heated by the heating roller 26b at a position where the heating roller 26b is wound around. On / off of power supply to the heat source of the heating roller 26b is controlled by a fixing temperature control unit (not shown). The fixing temperature control unit controls the above-described power supply on and off so that a detection result by a temperature sensor (not shown) that detects the surface temperature of the fixing belt 42 becomes a predetermined value.
A pressure roller 27 is brought into contact with a portion of the fixing belt 26 that moves endlessly with respect to the elastic driving roller 26a, and is rotated in the counterclockwise direction in the drawing while forming a fixing nip. The recording medium P that has passed through the secondary transfer nip described above is sent into the fixing device 25 and is sandwiched between the fixing nips. The toner image is fixed by the action of pressure and heating.

The cleaning web of the toner removal unit 26c is in contact with the fixing belt 26 after passing through the fixing nip. The toner that has adhered to the surface of the fixing belt 26 is wiped off by the cleaning web. The toner removing unit 26c winds a belt-shaped web around a winding roll. And the web extended | stretched from this winding roll can be wound up by rotation of a winding roll. A portion of the web between the winding roll and the winding roll is brought into contact with the fixing belt 26, and an appropriate amount of the web is wound according to the progress of the degree of dirt (wiping operation time) at the portion. By taking up with a take-up roll, a portion of the web that is not soiled is brought into contact with the fixing belt 26.
An oil application roller 26d is in contact with a portion where the fixing belt 26 is wound around the heating roller 26b. The oil application roller 26d rotates while being in contact with the surface of the fixing belt 26, thereby applying release oil as a release accelerator on the same surface. In this embodiment, silicone oil is used as the release oil.
In the vicinity of the oil application roller 26d, an oil tray 26g, an oil penetration felt 26f, and an oil supply roller 26e are disposed. Oil is stored in the oil tray 26g. The oil pan 26g is provided with an overflow pipe (not shown) that overflows the oil in the oil pan 26g at a predetermined height. Oil is regularly supplied to the oil receiving tray 26g by an oil supply device (not shown). At this time, excess oil is returned to the oil supply device via the overflow pipe.

The oil penetration felt 26f is partially immersed in the release oil in the oil tray 26g. This oil-penetrating felt 26f soaks the release oil into the non-penetrating portion with respect to the release oil by capillary action. The oil supply roller 26e rotates while being in contact with the oil permeation felt 26f and the oil application roller 26d, thereby applying the release oil wiped off from the oil permeation felt 26f to the oil application roller 26d. As a result, new release oil is supplied to the surface of the oil application roller 26 d that has lost the release oil due to oil application to the fixing belt 26.
The fixing device 25 suppresses toner offset with respect to the fixing belt 26 by applying release oil to the fixing belt 26 as described above. Further, the release oil applied to the fixing belt 26 is transferred to the pressure roller 27 at the fixing nip where the recording medium P is not sandwiched, so that the offset of the toner with respect to the pressure roller 27 is also suppressed.
In FIG. 1 described above, the recording medium P on which the toner image is transferred to the first surface at the secondary transfer nip and the toner image is fixed on the first surface (front surface) by the fixing device 25 is transported and switched. It is sent out toward the device 29.

In the image forming apparatus according to the present embodiment, the transport switching device 29, the retransmission path 54, the switchback path 55, the post-switchback transport path 56, and the like constitute a retransmission unit. Specifically, the transport switching device 29 switches the subsequent transport destination of the recording medium P received from the fixing device 25 between the paper discharge path 58 and the retransmission path 54. Specifically, when a single-sided mode print job for forming an image on only the first surface of the recording medium P is executed, the conveyance destination is set to the paper discharge path 58. As a result, the recording medium P on which the image is formed only on the first surface is sent to the paper discharge roller pair 52 via the paper discharge path 58 and discharged onto the paper discharge tray 57 outside the apparatus.
In addition, when executing a print job in a duplex mode in which images are formed on both sides of the recording medium P, when the recording medium P having images fixed on both sides is received from the fixing device 25, the transport destination is also set. The paper discharge path 58 is set. As a result, the recording medium P on which images are formed on both sides is discharged onto a discharge tray 57 outside the apparatus. On the other hand, when a recording medium P having an image fixed only on the first side is received from the fixing device 25 during execution of a double-side mode print job, the transport destination is set to the retransmission path 54.

A switchback path 55 is connected to the retransmission path 54, and the recording medium P sent to the retransmission path 54 enters the switchback path 55. When the entire area in the conveyance direction of the recording medium P enters the switchback path 55, the conveyance direction of the recording medium P is reversed and the recording medium P is switched back. In addition to the retransmission path 54, a post-switchback transport path 56 is connected to the switchback path 55, and the recording medium P that has been switched back enters the post-switchback transport path 56. At this time, the recording medium P is turned upside down. The recording medium P that is turned upside down is retransmitted to the secondary transfer nip via the post-switchback transport path 56 and the transport path 48 described above.
The recording medium P on which the toner image is also transferred to the second surface (back surface) at the secondary transfer nip is fixed on the second surface via the fixing device 25, and then the conveyance switching device 29, The paper is discharged onto a paper discharge tray 57 via a paper discharge path 58 and a pair of paper discharge rollers 52.
As described above, when image formation is performed on both surfaces of the recording medium P, if the image formation is performed via the fixing device that applies the above-described release oil, a toner image is formed on the first surface of the recording medium P. Release oil adheres to the second surface of the fixed recording medium P. As described above, when the toner image is transferred from the intermediate transfer belt 10 to the recording medium P having the release oil adhered to the second surface at the secondary transfer nip, the secondary transfer roller 22 and the intermediate transfer roller 22 constituting the secondary transfer nip are arranged. Release oil is transferred and adhered from the recording medium P to the transfer belt 10. Further, the release oil is transferred from the intermediate transfer belt 10 to the photoconductor 40 and the surface of the photoconductor 40 is contaminated.

On the other hand, in the tandem type image forming apparatus, the toner image of the process control toner density reference pattern that is not transferred to the recording medium P is transferred onto the intermediate transfer belt 10 during the continuous image forming operation for continuously forming images on the recording medium P. It is formed. The toner image of the toner density reference pattern formed on the intermediate transfer belt 10 is mainly removed by the belt cleaning device 17 described above. At this time, residual toner also adheres to the secondary transfer roller.
In order to remove the residual toner, in the image forming apparatus according to the present embodiment, a secondary transfer roller cleaning device 1 that removes the toner attached to the secondary transfer roller 22 is provided. As will be described later, the belt cleaning device 17 and the secondary transfer roller cleaning device 1 include the intermediate transfer belt 10 or the secondary transfer belt together with a cleaning blade that is in sliding contact with the surface of the intermediate transfer belt 10 or the surface of the secondary transfer roller 22. Lubricant application means for applying a lubricant to the surface of the transfer roller 22 is provided.

The lubricant application means includes a brush roller that is in sliding contact with the surface of the intermediate transfer belt 10 or the secondary transfer roller 22, and a solid lubricant that is in pressure contact with the brush roller. The lubricant is scraped off from the surface of the solid lubricant and applied to the surface of the rotating body.
In the secondary transfer roller cleaning device 1 and the belt cleaning device 17 as described above, when release oil or toner adheres to the rotating body as described above, it adheres to the surface of the solid lubricant via the brush roller, and the time passes. At the same time, it is firmly fixed, and it becomes difficult to remove the appropriate lubricant from the surface of the solid lubricant by the brush roller. As a result, the supply of the lubricant to the rotating body becomes insufficient, and the removal of toner and the like from the surface of the rotating body by the cleaning blade cannot be performed properly.
In the present invention, a cleaning device that suppresses the sticking of the solid lubricant surface to the surface of the solid lubricant by the mixture of the toner and the release oil and always supplies the lubricant appropriately to the surface of the rotating body to enable appropriate cleaning. And an image forming apparatus including the same.

The secondary transfer roller cleaning device, in which the mixture of the toner and the release oil easily adheres to the surface of the solid lubricant, will be described with reference to FIG. FIG. 4 is a diagram showing a schematic configuration of a secondary transfer roller cleaning device according to an embodiment of the present invention.
As shown in FIG. 4, the secondary transfer roller cleaning device 1 applies a lubricant to the outer peripheral surface 22 b of the secondary transfer roller 22 that is rotatably mounted in the case 2 with the rotary shaft 22 a as a support shaft. A coating blade 3 and a cleaning blade means 4 for removing toner and the like from the outer peripheral surface 22 b of the secondary transfer roller 22 are provided. The lubricant application means 3 is rotatably attached to the case 2 with the rotary shaft 5a as a support shaft, and is attached in the case 2 to the first brush roller 5 whose outer periphery is in sliding contact with the outer peripheral surface 22b of the secondary transfer roller 22. The solid lubricant 7 accommodated in the holder 6 and a spring member 6a attached in the holder 6 so that the tip 7a of the solid lubricant 7 is pressed against the outer periphery of the first brush roller 5 are provided. .
Accordingly, the first brush roller 5 and the secondary transfer roller 22 are driven to rotate in the directions indicated by arrows E and F by drive motors (not shown), respectively, so that the lubricant is scraped off from the tip 7a of the solid lubricant 7 and scraped off. The lubricant can be applied to the outer peripheral surface 22 b of the secondary transfer roller 22 to reduce the surface friction coefficient of the outer peripheral surface of the secondary transfer roller 22.

Further, the cleaning blade means 4 includes a blade 4 a made of a rubber member or the like whose tip is slid at an acute angle in the rotation direction F of the secondary transfer roller 22, and a blade holding member 4 b that holds the blade 4 a in the case 2. I have. Accordingly, when the secondary transfer roller 22 is rotated in the direction of the arrow F, foreign matters such as toner and paper dust attached to the outer peripheral surface 22b of the secondary transfer roller 22 are removed from the outer peripheral surface 22b of the secondary transfer roller 22. Then, the removed foreign matter is dropped and accommodated in the foreign matter accommodation recess 2 a in the case 2.
And the foreign material accommodated in the foreign material accommodation recessed part 2a is conveyed to the waste toner storage part which is not shown in figure by the conveyance screw 8 arrange | positioned in the foreign material accommodation recessed part 2a. Further, in the secondary transfer roller cleaning device 1 according to this embodiment, a second brush roller 9 for removing foreign matter such as toner and paper dust, which is rotatably mounted in the case 2 with the rotary shaft 9a as a support shaft, is arranged. Toner or paper attached to the outer peripheral surface 22b of the secondary transfer roller 22 in combination with the rotation of the secondary transfer roller 22 in the direction of arrow F and the rotation of the second brush roller 9 in the direction of arrow G Foreign matter such as powder is removed from the outer peripheral surface of the secondary transfer roller 22 and is dropped and accommodated in the foreign matter accommodation recess 2a.

Further, in the secondary transfer roller cleaning device 1, the case 2 is rotatably attached around the support shaft 11, and the drive means 12 is operated by the drive means 12 such as a solenoid that can be rotated in the direction of arrow H. Thus, the outer peripheral surface 22b of the secondary transfer roller 22 can be pressed against or separated from the intermediate transfer belt 10 toward the secondary transfer counter roller 16 (contact / separation mechanism). When a toner image is transferred from the surface of the intermediate transfer belt 10 to the recording medium P conveyed between the upper entrance guide plate 87 and the lower entrance guide plate 86 attached to the upper portion of the case 2, the secondary image is transferred. The transfer roller 22 is in pressure contact with the intermediate transfer belt 10, and the secondary transfer roller 22 and the intermediate transfer belt 10 are separated from each other except when the toner image is transferred.
The release oil that has adhered to the secondary transfer roller 22 during duplex printing adheres to the surface of the solid lubricant 7 via the first brush roller 5 as described above. In addition, when a large amount of toner adheres to the secondary transfer roller 22 such as when jamming, all the toner cannot be removed by the cleaning blade means 4, and the toner that cannot be removed passes through the brush roller 5 to the surface of the solid lubricant 7. Adhere to. If the solid lubricant 7 is left in a state in which release oil or toner is adhered, the mixture adheres to the front surface of the solid lubricant 7, and the solid lubricant 7 cannot be removed by the first brush roller 5. Cannot be applied.

Therefore, the secondary transfer roller 22 and the first brush roller 5 are in a state in which the secondary transfer roller 22 and the intermediate transfer belt 10 are separated before the mixture is fixed to the solid lubricant 7 by the release oil and toner after the printing operation is completed. And the release oil and toner adhering to the solid lubricant 7 by the first brush roller 5 are scraped off from the surface of the solid lubricant 7 to adhere to the outer peripheral surface 22b of the secondary transfer roller 22, and cleaning blade means 4 and the second brush roller 9 (collection prevention operation). More specifically, when the secondary transfer roller 22 is driven to rotate after the secondary transfer roller 22 is separated from the intermediate transfer belt 10, first, the release oil adhering to the secondary transfer roller 22 is removed by the cleaning blade means 4. Is done. When the amount of release oil adhering to the secondary transfer roller 22 decreases, the release oil adhering to the lubricant moves to the secondary transfer roller 22 via the first brush roller 5 this time. By removing the moved release oil by the cleaning blade means 4, it is possible to prevent the release oil from adhering to the solid lubricant.
Here, when the lubricant sticking prevention operation is performed in a state where the secondary transfer roller 22 and the intermediate transfer belt 10 are in contact with each other, the release oil is supplied to the secondary transfer roller 22, so the sticking to the solid lubricant is performed. In order to prevent this, the secondary transfer roller 22 needs to be rotationally driven over a longer time. Therefore, it is preferable to perform the lubricant sticking prevention operation in a state where the secondary transfer roller 22 and the intermediate transfer belt 10 are separated from each other.

Next, the rotational operation time of the secondary transfer roller 22 and the first brush roller 5 when performing such an operation for preventing the adhesion of the lubricant was examined. As a result, residual toner on the surface of the secondary transfer roller 22 can be cleaned only by setting the rotation speed of the secondary transfer roller 22 to 300 rpm and the time required to rotate the first brush roller 5 several times at 150 rpm. However, the release oil adhering to the solid lubricant could not be sufficiently moved to the secondary transfer roller 22.
Therefore, as a result of various experiments, in order to obtain the effect of the present invention, the secondary transfer roller 22 and the first brush roller 5 are driven to rotate for a longer time (for example, about several minutes) and adhere to the solid lubricant 7. It has been found that it is necessary to move the existing release oil to the secondary transfer roller 22.
Further, the removal of the release oil is sufficient after the printing of the toner image on the recording medium P is completed, but it is particularly effective to be performed at the end of the double-sided printing on the recording medium P. I understood. Further, the amount of adhesion of the secondary transfer roller 22 by the release oil changes according to the number of sheets of the recording medium P to be printed on both sides, and the amount of adhesion increases as the number of sheets to be passed increases. It has been found that it is necessary to lengthen the rotational operation time of the secondary transfer roller 22 and the first brush roller 5 when performing.

It has also been found that if the lubricant sticking prevention operation is performed immediately after the toner density reference pattern is formed on the intermediate transfer belt 10, sticking to the solid lubricant is effectively prevented. Similarly, it has been found that it is effective to perform the lubricant sticking prevention operation when the image forming apparatus such as a jam starts up after an abnormal stop.
From such experimental results, in order to reliably control the lubricant sticking prevention operation of the secondary transfer roller cleaning device 1, in the image forming apparatus according to the present embodiment, as shown in FIG. By using this, the contact / separation operation of the secondary transfer roller 22 and the rotation time of the secondary transfer roller 22 and the first brush roller are controlled. That is, the secondary transfer roller contact / separation driving unit 106 is driven by the control unit 105 by the input of the detection signal from the double-sided printing end detection unit 101, and the secondary transfer roller 22 is separated from the intermediate transfer belt 10.
The secondary transfer roller contact / separation driving means 106 is operated not by the detection signal of the double-sided printing end detection means 101 but by the detection signal when the toner image is transferred onto the recording medium P by the secondary transfer roller 22. Thus, the detection signal from the double-sided printing end detection unit 101 may confirm that the secondary transfer roller contact / separation drive unit 106 is in the separated state.

Thereafter, the secondary transfer roller 22 and the first brush roller 5 are controlled by controlling the drive motor for rotationally driving the secondary transfer roller 22 and the first brush roller 5 based on the detection signal from the double-sided printing end detection means 101. By rotating, the release oil and toner are removed from the surface of the solid lubricant 7. Further, the control unit 105 sets the operation time (rotation time) of the lubricant sticking prevention operation in accordance with the detection result from the double-side printed sheet passing number detection unit 102. Further, the detection unit 104 that detects the toner density reference pattern on the intermediate transfer belt 10 causes the control unit 105 to set the operation start and operation time of the lubricant sticking prevention operation and perform the lubricant sticking prevention operation. I have to. In addition, the start-up from the abnormal stop of the image forming apparatus is detected by the detection unit 103, and the operation of the lubricant sticking prevention operation is controlled by the control unit 105.
Further, in the control device shown in FIG. 5, the operation of the lubricant sticking prevention operation of the belt cleaning device 17 for the intermediate transfer belt, which will be described later, is controlled. Based on detection signals from the detection unit 102, the abnormal stop rise detection unit 103, and the toner density reference pattern image formation detection unit 104, the intermediate transfer belt drive unit 108, the intermediate transfer belt contact / separation unit 109, and the third belt cleaning unit. The brush motor driving motor 110 is controlled.
In the present embodiment, zinc stearate is used as the solid lubricant, and silicone oil is used as the release oil.

Next, in the above embodiment, the belt cleaning device 17 can also control the operation of the lubricant sticking prevention operation. FIG. 6 is a diagram showing a schematic configuration of a belt cleaning device according to an embodiment of the present invention.
As described above, the surface of the solid lubricant due to the release oil also occurs in the lubricant application means in the belt cleaning device 17. Therefore, in the present embodiment, the lubricant application unit is controlled to perform the operation of the lubricant sticking prevention operation. First, the configuration of the belt cleaning device 17 will be described with reference to FIG.
The belt cleaning device 17 according to this embodiment includes a lubricant applying unit 70 that applies a lubricant from a solid lubricant to the surface of the intermediate transfer belt 10, and a cleaning that removes release oil and toner from the surface of the intermediate transfer belt 10. Blade means 71. The lubricant application means 70 is rotatably attached to the case 75 about the rotation shaft 73a as a support shaft, and a third brush roller 73 that is in sliding contact with the intermediate transfer belt 10 by the brush roller facing roller 65, and a holder attached in the case 75. The solid lubricant 74 housed in 77 and a spring member 77 a attached in the holder 77 so that the tip 74 a of the solid lubricant 74 is pressed against the outer periphery of the third brush roller 73. Accordingly, the third brush roller 73 is driven to rotate in the direction indicated by the arrow I by a drive motor (not shown), whereby the lubricant is scraped off from the tip 74a of the solid lubricant 74, and the scraped lubricant is removed from the intermediate transfer belt 10. The surface friction coefficient of the surface of the intermediate transfer belt 10 can be reduced by applying to the surface.

The cleaning blade means 71 includes a blade 72 a made of a rubber member or the like whose tip is slid in an acute angle toward the transfer direction A of the intermediate transfer belt 10, and a blade holding member 72 b that holds the blade 72 a in the case 75. ing. Accordingly, when the intermediate transfer belt 10 is moved in the direction of arrow A, the release oil, toner, paper dust and other foreign matters adhering to the surface of the intermediate transfer belt 10 are removed from the surface of the intermediate transfer belt 10 and removed. The foreign matter is dropped and accommodated in the foreign matter accommodation recess 75 a in the case 75. The foreign matter stored in the foreign matter storage recess 75a is transported to a waste toner storage portion (not shown) by a transport screw 78 disposed in the foreign matter storage recess 75a.
In addition, the belt cleaning device 17 according to this embodiment includes a fourth brush roller 79 for removing foreign matter such as toner and paper dust that is rotatably mounted in a case 75 with a rotating shaft 79a as a supporting shaft. In combination with the transfer of the intermediate transfer belt 10 in the direction of arrow A and the rotation of the fourth brush roller 79 in the direction of arrow J, foreign matters such as toner and paper dust adhering to the surface of the intermediate transfer belt 10 are intermediate transferred. The belt 10 is removed from the surface of the belt 10 and is dropped and accommodated in the foreign matter accommodation recess 75a.

  Further, in the belt cleaning device 17, when the lubricant sticking prevention operation of the solid lubricant 74 is performed, it is performed as follows. That is, the secondary transfer roller cleaning device 1 described above is operated to separate the secondary transfer roller 22 from the intermediate transfer belt 10, and an intermediate transfer belt contacting / separating means 109 (see FIG. 5) (not shown) is operated to perform intermediate operation. The transfer belt 10 is moved away from the photoreceptors 40Y, 40M, 40C, and 40K, and the intermediate transfer belt 10 is moved in the direction of arrow A. As a result, the toner adhering to the intermediate transfer belt 10, release oil, and the like are removed from the intermediate transfer belt 10 by the blade 72 a and the third brush roller 73 is rotated to remove the surface of the solid lubricant 74. The release oil, toner, and the like adhering to the surface are scraped off from the surface of the solid lubricant 74 and adhered to the surface of the intermediate transfer belt 10. Thus, the release oil, toner, and the like attached on the intermediate transfer belt 10 by the third brush roller 73 are scraped off and removed by the blade 72a.

The lubricant cleaning prevention operation of the belt cleaning device 17 is lubricated with release oil and toner after the printing operation, for example, using the control device 100 shown in FIG. 5 in the same manner as the secondary transfer roller cleaning device 1 described above. Before the agent is fixed, the intermediate transfer belt 10 and the belt cleaning device 17 are driven in a state where the intermediate transfer belt 10 and the secondary transfer roller 22 and the photoreceptor 40 are separated from each other, and the solid lubricant 74 is driven by the third brush roller 73. The release oil and toner adhering to the toner are collected and adhered to the intermediate transfer belt 10, and collected by the cleaning blade means 71.
In this way, by controlling the rotation of the third brush roller 73, it is possible to prevent the mixture of the release oil and the toner from adhering to the tip of the solid lubricant 74, and to properly apply the lubricant to the surface of the intermediate transfer belt 10. Can be applied. As a result, the cleaning effect of the intermediate transfer belt 10 by the belt cleaning device 17 can be maintained for a long time.

In the image forming apparatus according to the above-described embodiment of the present invention, there are provided two cleaning devices, a secondary transfer roller cleaning device 1 and a belt cleaning device 17 for cleaning the secondary transfer roller 22 and the intermediate transfer belt 10, respectively. ing. In this case, since the mixture of the release oil and the toner with the solid lubricant 7 in the lubricant applying means 3 of the secondary transfer roller cleaning device 1 is likely to be fixed, the operation of preventing the lubricant from fixing with the belt cleaning device 17 is performed. The operation time is set longer. By doing so, the cleaning effect on the secondary transfer roller 22 and the intermediate transfer belt 10 can be more appropriately performed.
In the present invention, the cleaning device for the photoconductor 40 shown in FIG. 2 and the lubricant application means 35 in the photoconductor cleaning device 30 are also similar to the secondary transfer roller cleaning device 1 and the belt cleaning device 17 described above. In addition, control may be performed so as to perform the lubricant sticking prevention operation.
In the embodiment according to the present invention, a drum-shaped photosensitive member is used as the photosensitive member 40, but a belt-shaped photosensitive member may be used. Similarly, although the secondary transfer roller is used as the secondary transfer member, a secondary transfer member in which an endless belt is stretched around a support roller may be used. In the above embodiment, the intermediate transfer belt is used as the intermediate transfer member. However, an intermediate transfer drum may be used.

  DESCRIPTION OF SYMBOLS 1 ... Secondary transfer roller cleaning apparatus, 2 ... Case, 3, 35, 70 ... Lubricant application means 4, 71 ... Cleaning blade means, 5 ... 1st brush roller, 6, 77 ... Holder, 7, 34, 74 ... Solid lubricant, 8, 78 ... Conveying screw, 9 ... Second brush roller, 10 ... Intermediate transfer belt, 11, 80 ... Support shaft, 12, 81 ... Driving means, 16 ... Support roller (secondary transfer counter roller) , 17 ... belt cleaning device, 18Y, 18M, 18C, 18K ... image forming unit, 21 ... optical writing device, 22 ... secondary transfer roller, 25 ... fixing device, 26 ... fixing belt, 26d ... oil application roller, 27 ... Pressure roller, 30 ... photoconductor cleaning device, 31 ... cleaning blade, 32 ... cleaning brush roller, 33 ... brush roller, 40, 40Y, 40M, 0C, 40K ... photosensitive member, 54 ... retransmission path, 55 ... switchback path, 55 ... conveying path after switchback, 73 ... third brush roller, 100 ... control device, 101 ... double-sided printing end detection means, 102 ... double-sided printing Number of passing sheets detection means, 103 ... Abnormal stop start detection means, 104 ... Toner density reference pattern image formation detection means, 105 ... Control unit, 106 ... Secondary transfer roller contact / separation mechanism driving means, 107 ... Secondary transfer roller and 1st brush roller drive motor, 108 ... intermediate transfer belt drive means, 109 ... intermediate transfer belt contact / separation means, 110 ... 3rd brush roller drive motor

Japanese Patent Laid-Open No. 5-323704 JP 2004-177442 A JP 2004-94055 A Japanese Patent No. 3876581

Claims (11)

Lubricant application means for applying a lubricant to the surface of the rotating body to which the toner and release oil adhere, and a cleaning blade for removing the toner and release oil attached to the surface of the rotating body from the surface of the rotating body. In the cleaning device,
The lubricant application means includes a brush roller that is in sliding contact with the surface of the rotating body, and a solid lubricant that is in pressure contact with the brush roller, and the lubricant is removed from the surface of the solid lubricant by the rotation of the brush roller. Is applied to the surface of the rotating body,
The cleaning device according to claim 1, wherein the brush roller is controlled so as to perform a lubricant sticking prevention operation for scraping off toner and release oil adhered to the surface of the solid lubricant by being driven to rotate after completion of printing. The cleaning device according to claim 1.
The rotator transfers a photosensitive member on which a toner image is formed on the surface, an intermediate transfer member to which the toner image formed on the photosensitive member is transferred, or a toner image on the intermediate transfer member onto a recording medium. A cleaning device which is one of secondary transfer members. The cleaning device according to claim 2, wherein
The cleaning device, wherein the rotating body is a secondary transfer member. The cleaning device according to claim 3.
The secondary transfer member is detachably attached to the intermediate transfer member, and is controlled to perform the lubricant sticking prevention operation when the secondary transfer member is separated from the intermediate transfer member. A cleaning device.   An image forming apparatus comprising the cleaning device according to claim 1. The image forming apparatus according to claim 5.
The image forming apparatus includes a double-sided image forming unit that reversely travels a recording medium having a toner image fixed on a surface thereof to form a toner image on a back surface of the recording medium. The image forming apparatus according to claim 6.
2. The image forming apparatus according to claim 1, wherein the lubricant sticking prevention operation is performed after the operation of forming an image on both sides of the recording medium is completed. The image forming apparatus according to claim 7.
An image forming apparatus, wherein the rotation time of the brush roller in the lubricant sticking prevention operation is changed according to the number of sheets to be image-formed on both sides of the recording medium. The image forming apparatus according to any one of claims 5 to 8,
The image forming apparatus, wherein the lubricant sticking prevention operation is performed after a toner density reference pattern image is formed or transferred to the rotating body. The image forming apparatus according to any one of claims 5 to 9,
2. The image forming apparatus according to claim 1, wherein the lubricant sticking prevention operation is performed when the image forming apparatus is started up after an abnormal stop. The image forming apparatus according to claim 5, wherein:
The cleaning device is provided for a plurality of the rotating bodies, and the rotating body in which the toner and the release oil are more likely to adhere to the solid lubricant has a longer rotation time of the brush roller when the brush roller is controlled. An image forming apparatus characterized by being made longer.

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