JP5849461B2 - Image forming apparatus and cleaning apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus and a cleaning apparatus.

  Conventionally, an image forming apparatus that forms a toner image on a sheet is known, and this image forming apparatus executes a series of processes of transferring a toner image onto a sheet and fixing the transferred toner image on the sheet. . In the image forming apparatus, when toner is transferred to a sheet, if residual toner adheres to a transfer member that comes into contact with the sheet, the toner may move to the sheet and cause dirt and the like. For this reason, the image forming apparatus includes a cleaning device for cleaning the transfer member in order to remove residual toner attached to the transfer member. Here, the adhesion of the residual toner to the transfer member may occur due to factors such as double-sided printing on the paper as an example. Specifically, when the paper is transported for image formation on the back surface, if toner on the front surface of the paper adheres to the transport member (transport roller or transport belt), this adheres to the subsequent paper and is transported. . Then, when the succeeding sheet passes through the transfer member, the toner adhered to the sheet adheres to the transfer member.

  For example, Patent Document 1 discloses a first cleaning member that contacts the transfer belt, and a second cleaning member that is provided upstream of the first cleaning member in the rotation direction of the transfer belt and contacts the transfer belt. A cleaning device is disclosed. According to this cleaning device, the residual toner on the transfer belt is temporarily removed by the second cleaning member disposed upstream of the first cleaning member.

Japanese Patent Laid-Open No. 2002-40894

  By the way, when the second cleaning member is provided upstream of the first cleaning member, relatively large residual toner can be removed in advance, so that the first cleaning member is not provided. The wear of the cleaning member can be suppressed. However, due to the presence of the second cleaning member, the contact state between the transfer member and the first cleaning member may differ from the desired state, and good cleaning performance can be obtained with good durability. There was an inconvenience that it was not possible.

  The present invention has been made in view of such circumstances, and an object of the present invention is to maintain a good contact state between the first cleaning member on the downstream side of the second cleaning member and the transfer member. In other words, good cleaning performance is obtained with good durability.

In order to solve such a problem, the first invention is configured to be rotatable in correspondence with the conveyance direction of the paper, and a contact surface between the transfer member for transferring the toner image to the conveyed paper and the paper. A first cleaning member that contacts the outer peripheral surface of a transfer member and removes toner adhering to the outer peripheral surface of the transfer member, and is disposed upstream of the first cleaning member in the rotation direction of the transfer member. A second cleaning member that contacts the outer peripheral surface of the transfer member and removes toner adhering to the outer peripheral surface of the transfer member; and a transport unit that includes a plurality of transport members that transport the paper according to each rotation. An image forming apparatus is provided. In this case, the second cleaning member has a difference in toner removal force with respect to the transfer member with respect to the sheet width direction orthogonal to the sheet conveyance direction. In the second region which does not correspond to the conveying member, the toner removing force is set smaller.

  In addition, the second invention is configured to be rotatable in correspondence with the conveyance direction of the paper, and a transfer member that transfers the toner image onto the conveyed paper and an outer peripheral surface of the transfer member that is a contact surface with the paper And a first cleaning member that removes toner adhering to the outer peripheral surface of the transfer member and an upstream side of the first cleaning member in the rotation direction of the transfer member, and the outer periphery of the transfer member Provided is an image forming apparatus having a second cleaning member that contacts the surface and removes toner adhering to the outer peripheral surface of the transfer member. In this case, the second cleaning member is a scraper including a resin sheet-like member and a support member that supports the sheet-like member, and the free end side of the sheet-like member is an outer peripheral surface of the transfer member. The toner removal force with respect to the transfer member is different with respect to the paper width direction perpendicular to the paper transport direction.

In the second invention , the second cleaning member is preferably arranged so that the extending direction of the sheet-like member from the fixed end to the free end faces the rotation direction of the transfer member.

In the second invention , the second cleaning member may provide a difference in toner removal force by providing a difference in the length from the edge of the support member to the free end of the sheet-like member. preferable.

In the second invention , the second cleaning member preferably removes the toner, the wax contained in the toner together with the toner, or the wax applied to the fixing member as a release material.

In the second invention, the transfer member may be a photoconductor more to pressure via an intermediate transfer member and the sheet on which the toner image is transferred, a secondary transfer member for transferring the toner to the paper preferable. Alternatively, the transfer member may be an intermediate transfer member that transfers the toner image transferred from the photosensitive member to the sheet by pressing the secondary transfer member through the sheet.

  According to the present invention, since there is a difference in the toner removal force with respect to the transfer member in the paper width direction, among the toner adhering to the transfer member, what passes through the second cleaning member and what is removed Selection can be made according to the position in the paper width direction. As a result, a situation in which the toner is uniformly removed can be suppressed, and the contact state between the first cleaning member and the transfer member on the downstream side can be kept good. Thereby, favorable cleaning performance can be obtained with good durability by the cooperation of the two cleaning members.

Explanatory drawing which shows the structure of the image forming apparatus 1 typically. The block diagram which shows typically the principal part of the image forming apparatus 1 centering on the secondary transfer part 45 Explanatory drawing which shows the structure of the 1st cleaning member 51 and the 2nd cleaning member 52 typically. Explanatory drawing which shows another form of the 2nd cleaning member 52 typically. Explanatory drawing which shows another form of the 2nd cleaning member 52 typically. Explanatory drawing which shows another form of the 2nd cleaning member 52 typically. Explanatory drawing which shows typically another form of the image forming apparatus 1

  FIG. 1 is an explanatory diagram schematically showing a configuration of an image forming apparatus 1 according to the present embodiment. The image forming apparatus 1 is an electrophotographic image forming apparatus such as a copying machine, and forms a full-color image by arranging a plurality of photosensitive drums facing a single intermediate transfer belt in a vertical direction. This is a so-called tandem color image forming apparatus.

  The image forming apparatus 1 includes a document reading device 10, image forming units 30Y, 30M, 30C, and 30K, an intermediate transfer unit 40, a secondary transfer unit 45, a fixing device 60, a paper discharge reversing unit 70, a refeed unit 80, The sheet feeding unit 90 and the control unit 100 are mainly configured, and these are housed in one casing.

  The document reading apparatus 10 includes an automatic document feeder ADF on the top thereof. The documents D placed on the document placement table 15 of the automatic document feeder ADF are separated one by one, sent out to the document conveyance path, and conveyed by the conveyance drum 16. The first transport guide G 1 and the document discharge roller 17 discharge the document D transported by the transport drum 16 to the document discharge tray 18.

  The document reading device 10 reads an image of the document D being conveyed by the conveyance drum 16 at the document image reading position RP. Specifically, the image of the document D is irradiated with the lamp L at the document image reading position RP. Reflected light by irradiation is guided by the first mirror unit 11, the second mirror unit 12, and the lens unit 13 and forms an image on the light receiving surface of the image sensor CCD. The imaging device CCD photoelectrically converts incident light and outputs a predetermined image signal. The output image signal is created as image data by performing A / D conversion.

  The image reading control unit 14 performs processing such as shading correction, dither processing, and compression on the image data, and stores the image data obtained by this processing in a storage unit such as a RAM of the control unit 100. The image data may be received from a personal computer connected to the image forming apparatus 1 or another image forming apparatus as well as data output from the document reading apparatus 10.

  The image forming unit 30Y includes an exposure unit 20Y, a photosensitive drum 31Y, and a main charging unit 32Y, a developing unit 33Y, a first transfer roller 34Y, and a cleaning unit 35Y that are arranged around the photosensitive drum 31Y. Thus, an image (toner image) corresponding to yellow is formed. The other image forming units 30M, 30C, and 30K have the same configuration as the image forming unit 30Y. The exposure units 20M, 20C, and 20K, the photosensitive drums 31M, 31C, and 31K, and the photosensitive drums 31M, 31C, and 31K. Is composed of main charging units 32M, 32C, 32K, developing units 33M, 33C, 33K, first transfer rollers 34M, 34C, 34K, and cleaning units 35M, 35C, 35K. An image (toner image) corresponding to each color of cyan and black is formed.

  The exposure units 20Y to 20K include a laser light source, a polygon mirror, a plurality of lenses, and the like (not shown), and generate a laser beam. Each of the exposure units 20Y to 20K corresponds to the output information output from the control unit 100 based on the image data, and the surface of the corresponding photosensitive drum 31Y to 31K is irradiated with laser light in the axial direction (main scanning direction). Scan repeatedly. By this scanning exposure, latent images are formed on the photosensitive drums 31Y to 31K, respectively.

  The surfaces of the photosensitive drums 31Y to 31K are uniformly charged by the main charging portions 32Y to 32K. The developing units 33Y to 33K develop latent images on the photosensitive drums 31Y to 31K by developing with toner. As a result, toner images are formed on the respective photosensitive drums 31Y to 31K. The first transfer rollers 34Y to 34K sequentially transfer the toner images formed on the photosensitive drums 31Y to 31K to predetermined positions on the intermediate transfer unit 40 (specifically, the intermediate transfer belt 41). The cleaning units 35Y to 35K remove the toner remaining on the surfaces of the photosensitive drums 31Y to 31K after the transfer of the toner image.

  The intermediate transfer unit 40 is mainly composed of an intermediate transfer belt 41. The intermediate transfer belt 41 is stretched around a plurality of rollers, and is configured to be rotatable in correspondence with the transport direction of the paper P (hereinafter referred to as “paper transport direction”) FD. On the intermediate transfer belt 41, four image forming units 30Y to 30K are arranged to face each other. When the toner image is transferred from each of the image forming units 30Y to 30K to the outer peripheral surface, the intermediate transfer belt 41 conveys the toner image to a transfer position corresponding to the pressure contact portion with the secondary transfer unit 45 through its own rotating operation. To do. Then, at the transfer position, the outer peripheral surface of the intermediate transfer belt 41 comes into contact with the conveyed paper P, so that the toner image transferred onto the outer peripheral surface of the belt is transferred to the paper P. The belt cleaning device 43 cleans the surface of the intermediate transfer belt 41 that has finished transferring the toner image onto the paper P.

  The secondary transfer unit 45 transfers the toner image transferred onto the outer peripheral surface of the intermediate transfer belt 41 to the sheet P by contacting the sheet P being conveyed at the transfer position. One of the features of this embodiment is the configuration of the cleaning device 50 disposed in the secondary transfer unit 45, and details thereof will be described later.

  The paper P to be transferred to the toner image is supplied from one of the trays PG1, PG2, and PG3 constituting the paper supply unit 90, and is sent to the transfer position while being timed by the registration roller.

  The fixing device 60 fixes the toner image on the paper P by pressurizing and heating the paper P on which the toner image is fixed. For example, the fixing device 60 includes a fixing upper roller 61 and a fixing lower roller 62 which are a pair of fixing members. The upper fixing roller 61 and the lower fixing roller 62 are arranged in pressure contact with each other, and a fixing nip portion is formed as a pressing portion between the upper fixing roller 61 and the lower fixing roller 62.

  Inside the fixing upper roller 61, a heating unit (for example, a heater) for heating the fixing upper roller 61, that is, for thermally fixing the toner image on the paper P is incorporated. The fixing upper roller 61 is heated by the radiant heat from the heating means, and the heat of the fixing upper roller 61 is transmitted to the paper P.

  In the fixing device 60, the paper P is conveyed in such a manner that the surface to be fixed faces the fixing upper roller 61, and passes through the fixing nip portion during the conveyance process of the paper P. As a result, the toner image is fixed onto the paper P through the pressurization by the upper fixing roller 61 and the lower fixing roller 62 and the action of the heat of the upper fixing roller 61.

  The paper discharge reversing unit 70 conveys the paper P that has undergone the fixing process by the fixing device 60 and discharges it to the paper discharge tray 75. When the paper P is reversed and discharged, the paper discharge guide 72 once guides the paper P downward. The paper discharge reversing roller 73 holds the rear end of the paper P and then reversely conveys the paper P. Then, the paper discharge guide 72 guides the paper P to the paper discharge roller 74 so that the paper P is discharged to the paper discharge tray 75. Is done.

  In addition, in the case of double-sided printing in which image formation is performed on each of the front and back surfaces of the paper P instead of single-sided printing in which image formation is performed only on the front surface of the paper P, the paper discharge guide 72 performs fixing processing of the toner image on the front surface. The finished paper P is conveyed to the re-feeding unit 80 below. A reversing roller 81, which is one of the components of the paper refeeding unit 80, reverses the paper P by nipping the rear end of the paper P and then sends it to the paper refeeding conveyance path 82. As a result, the paper P is used for image formation on the back surface via the re-feed conveyance path 82.

  In the image forming apparatus 1, the refeed unit 80 and the paper feed unit 90 that feeds the paper P have a function as a transport unit that transports the paper P, and the refeed unit 80 and the paper feed unit. The unit 90 includes a guide member and a plurality of conveyance members (for example, conveyance rollers and conveyance belts) that rotate and convey the paper P.

  FIG. 2 is a configuration diagram schematically showing a main part of the image forming apparatus 1 centering on the secondary transfer unit 45. The secondary transfer unit 45 is mainly composed of a secondary transfer roller 46, a driving roller 47, a driven roller 48, a secondary transfer belt 49, and a cleaning device 50. The secondary transfer belt 49 is stretched around the secondary transfer roller 46, the driving roller 47, and the driven roller 48, and is configured to be rotatable in correspondence with the paper transport direction FD. At the transfer position corresponding to the pressure contact portion with the intermediate transfer belt 41, the outer peripheral surface of the secondary transfer belt 49 is transferred to the intermediate transfer belt 41 by contacting the intermediate transfer belt 41 via the sheet P being conveyed. The transferred toner image is transferred to the paper P.

  The cleaning device 50 includes a first cleaning member 51 and a second cleaning member 52, and is disposed in contact with the outer peripheral surface of a secondary transfer belt 49 that is a transfer member. The individual cleaning portions 51 and 52 are arranged in the order of the second cleaning member 52 and the first cleaning member 51 from the upstream side to the downstream side in the rotation direction of the secondary transfer belt 49, and the secondary transfer belt 51. 49 has a function of removing the residual toner adhering to the outer peripheral surface 49.

  Here, when the paper P is transported for image formation on the back surface, the residual toner adheres to the front surface or back surface of the succeeding paper P when the paper surface toner adheres to the transport member. By being conveyed together with P, when the succeeding sheet P passes through the secondary transfer belt 49, the toner remains attached to the secondary transfer belt 49 from the succeeding sheet P or other factors. Toner that adheres to the secondary transfer belt 49 and remains. The residual toner includes not only the toner itself but also adhered substances such as wax (wax added to the toner or wax applied to the fixing rollers 61 and 62 of the fixing device 60 as a release material).

  Of the pair of cleaning units 51 and 52, the second cleaning member 52 has a function of removing a large lump of residual toner prior to the removal of the residual toner by the first cleaning member 51. On the other hand, the first cleaning member 51 has a function of finally removing the residual toner that has passed through the second cleaning member 52.

  The first cleaning member 51 is a rubber blade, for example, a sheet-like member (hereinafter referred to as a “first sheet-like member”) 51a formed of an elastic body such as polyurethane rubber, and a first sheet-like member 51a. And a support member (hereinafter referred to as “first support member”) 51b.

  In the state supported by the first support member 51 b, the free end (tip) side of the first sheet-like member 51 a is pressed against the outer peripheral surface of the secondary transfer belt 49. The first sheet-like member 51a is pressed against the secondary transfer belt 49 with a predetermined force, and is in surface contact with the secondary transfer belt 49 in a partial region on the free end side, The secondary transfer belt 49 is bent so as to be convex toward the belt surface side. In addition, the extending direction from the fixed end to the free end of the first sheet-like member 51a is set to a direction opposite to the rotation direction of the secondary transfer belt 49 (that is, the movement direction by the rotation), so-called counter direction. Has been.

  The second cleaning member 52 is a scraper, for example, a sheet-like member (hereinafter referred to as “second sheet-like member”) 52a formed of a resin such as polypropylene, and a support member that supports the second sheet-like member 52a. (Hereinafter referred to as “second support member”) 52b.

  In the state supported by the second support member 52 b, the free end (tip) side of the second sheet-like member 52 a is pressed against the outer peripheral surface of the secondary transfer belt 49. The second sheet-like member 52a is pressed against the secondary transfer belt 49 with a predetermined force, and is in surface contact with the secondary transfer belt 49 in a partial region on the free end side, The secondary transfer belt 49 is bent so as to be convex toward the belt surface side. The extending direction from the fixed end to the free end of the second sheet-like member 52a is set to the counter direction.

  FIG. 3 is an explanatory diagram schematically showing the configuration of the first cleaning member 51 and the second cleaning member 52. In the first cleaning member 51, the height (the length corresponding to the counter direction) of the first support member 51b is set to a constant value regardless of the position in the paper width direction CD. On the other hand, the edge on the free end side of the first sheet-like member 51a extends linearly in the sheet width direction CD, and the first sheet-like member 51a starts from the edge of the first support member 51b. (The length to the free end corresponding to the counter direction) is also set to a constant value regardless of the position in the sheet width direction CD. Due to such a shape, in the first cleaning member 51, the pressing force of the first sheet-like member 51a against the secondary transfer belt 49 is set to be uniform in the paper width direction CD. Since the pressing force of the first sheet-like member 51a against the secondary transfer belt 49 corresponds to the residual toner removing force against the secondary transfer belt 49, the first cleaning member 51 is related to the sheet width direction CD. The residual toner removal force is set to be uniform.

  In contrast, in the second cleaning member 52, the height of the second support member 52b is set to an arbitrary value according to the position in the paper width direction CD. On the other hand, the edge on the free end side of the second sheet-like member 52a extends linearly in the sheet width direction CD, and the second sheet-like member starts from the edge of the second support member 52b. The height of 52a differs depending on the position in the paper width direction CD. Due to such a shape, the second cleaning member 52 has a difference in the force with which the second sheet-like member 52a is pressed against the secondary transfer belt 49 in the paper width direction CD. That is, the pressing force of the second sheet-like member 52a against the secondary transfer belt 49 corresponds to the removal force of the residual toner against the secondary transfer belt 49. Therefore, the second cleaning member 52 has the sheet width direction CD. Therefore, a difference is provided in the removal power of the residual toner.

  Specifically, as shown in FIG. 3, in the second support member 52b, the first area A1 is compared with the second area A2, which is the remaining area excluding the first area A1. The height of the second support member 52b is set large. When the height of the second support member 52b is large, since the height of the second sheet-like member 52a is relatively small, the pressing force by the second sheet-like member 52a in the first region A1 is It becomes larger than that of the second region A2. Therefore, in the second cleaning member 52, the residual toner removing power in the first area A1 is set to be larger than the residual toner removing power in the second area A2. In this case, the first area A1 in which the residual toner removing power is increased is, as indicated by the alternate long and short dash line in the figure, the transport member Rp (for example, the transport roller or the transport belt) of the refeed unit 80 that reversely transports the paper P. ) And position.

  In the second support member 52b, the height of the support member 52b is set to a constant value in the region corresponding to both ends (third region A3) in the second region A2. That is, in the second support member 52b, the residual toner removing force in the third region A3 is set to a constant value that is smaller than that of the first region A1. In the second region A2 excluding the third region A3, the height of the support member 52b is set to be linearly decreased from the first region A1 toward the third region A3. . Therefore, in the second support member 52b, the residual toner removing force in the second area A2 is set to be smaller as the distance from the first area A1 increases.

  As described above, in the present embodiment, the cleaning device 50 includes the first cleaning member 51 and the second cleaning member 52 disposed on the upstream side thereof, and the second cleaning member 52 is a sheet. With respect to the width direction CD, there is a difference in the residual toner removing force with respect to the secondary transfer belt 49.

  When a large amount of residual toner adheres to the secondary transfer belt 49, this causes wear of the first cleaning member 51. Therefore, the second amount of toner is removed for the purpose of removing the large amount of residual toner in advance. A cleaning member 52 is provided. The wear of the first cleaning member 51 is also caused by a large lump of residual toner corresponding to the toner, but the tendency is particularly noticeable depending on the one corresponding to the wax. That is, if the second cleaning member 52 is disposed on the upstream side and the wear of the first cleaning member 51 can be suppressed, the durability of the first cleaning member 51 is improved. As a result, the first cleaning member 51 can remove the remaining residual toner excluding a large lump of residual toner with good cleaning performance and high durability.

  In addition, the second cleaning member 52 preferably does not remove all of the residual toner, but preferentially removes a large lump of residual toner and allows the remaining residual toner to pass through. This is because the remaining residual toner is passed and becomes a lubricant for the first cleaning member 51. As a result, it is possible to suppress a situation in which the contact state between the secondary transfer belt 49 and the first cleaning member 51 is different from a desired state, for example, the first cleaning member 51 is turned over. It is. As a result, a good cleaning performance for the secondary transfer belt 49 can be obtained with high durability by the multi-stage configuration of the first and second cleaning members 51 and 52.

However, when the removal force of the residual toner by the second cleaning member 52 is set uniformly with respect to the paper width direction CD, the residual toner is uniformly removed without distinction such as large residual toner or residual residual toner. There is a possibility that. However, according to the present embodiment, a difference is provided in the residual toner removal force with respect to the secondary transfer belt 49 with respect to the paper width direction CD, and therefore the second cleaning member 52 out of the residual toner on the secondary transfer belt 49. Can be selected depending on the position in the paper width direction CD. Therefore, since the residual toner is not uniformly removed, the contact state between the first cleaning member 51 on the downstream side and the secondary transfer belt 49 can be kept good as described above. Thereby, by the cooperation of the first and second cleaning members 51 and 52 , good cleaning performance can be obtained with good durability.

  Further, the residual toner adhering to the secondary transfer belt 49 is caused by the conveyance process of the paper P, that is, the contact between the conveyance member and the paper P. Therefore, in the present embodiment, the second cleaning member 52 uses the removal force of the second region A2 that does not correspond in position to the conveyance member (conveyance roller or conveyance belt) that conveys the paper P to the position of the conveyance member. Therefore, it is set smaller than the removal force of the corresponding first region A1. As a result, in the second area A2 where there is little residual toner remaining in the large mass, the residual toner is not removed with the same removal force as in the first area A1, so that the residual toner The part can be passed downstream. As a result, it is possible to suppress a situation in which residual toner is uniformly removed without distinction of residual toner in the paper width direction CD.

  The cause of the residual toner can be generated particularly in the refeed unit 80. Therefore, the first region A1 and the second region A2 are positioned corresponding to the transport member Rp of the refeed unit 80. It is preferable to set.

  Further, the second cleaning member 52 has the removal force of the third region A3 corresponding to a predetermined range including both ends fixed to a predetermined magnitude, and the removal force of the third region A3 is the first removal force. It is smaller than the removal force set corresponding to the region A1. The situation such as the turning of the first cleaning member 51 as described above is particularly likely to occur at both ends thereof. Therefore, for the third region A3, from the viewpoint of curling suppression, a first cleaning member such as curling is set, for example, by setting a residual toner removing force that does not excessively remove the residual toner. It is possible to suppress a situation in which a change occurs in the contact state between the belt 51 and the secondary transfer belt 49.

  In addition to the above-described forms, various forms are conceivable as the form of setting the residual toner removal force by the second region A2. For example, as shown in FIG. 4, the removal force in the second region A2 may be uniform in a range smaller than the removal force in the first region A1. In the figure, (a) shows a form in which the removal force of the second region A2 is the same as the removal force of the third region A3. On the other hand, (b) shows a mode in which the removal force of the second region A2 is set to an intermediate value between the removal force of the first region A1 and the removal force of the third region A1.

  In the present embodiment, the second cleaning member 52 is provided with a difference in the length from the edge of the second support member 52b to the free end of the second sheet-like member 52a, so that the toner can be removed. There is a difference in removal power. According to such a configuration, the rigidity of the second sheet-like member 52a can be set by adjusting the length to the free end, and therefore the toner removal force can be easily set according to the degree of the rigidity. be able to.

  In addition to the above-described embodiment, as shown in FIG. 5, the height of the second support member 52b is set to a constant value regardless of the position in the paper width direction CD, and the second sheet-like member 52a. Is set to an arbitrary value according to the position in the paper width direction CD. Even in such a configuration, since the length to the free end can be adjusted, the toner removal force can be easily set.

  In the above-described embodiment, the transport member Rp is also set based on the center, assuming a mode in which the paper P is transported based on the center position of the transport path. However, as shown in FIG. 6, when the paper P is transported based on the end position Edg instead of the center position Cnt of the transport path, the transport member Rp is also set based on the end section. Even in this case, similarly, it is preferable to set the first region A1 and the second region A2 in correspondence with the transport member Rp.

  In the end region, there is a concern that the first cleaning member 51 is turned over. Therefore, the second cleaning member 52 fixes the removal force of the third region A3 to a predetermined size (a size in a range smaller than the first region A1) regardless of the position of the transport member Rp. It is preferable to keep it.

  In the above-described embodiment, the present invention has been described with respect to the cleaning device 50 for the secondary transfer belt 49. However, as shown in FIG. 2, the residual toner may adhere to the front and back sides of the paper P. Therefore, the present invention is applied to the belt cleaning device 43 for the intermediate transfer belt 41 as shown in FIG. Also good.

  The image forming apparatus according to the embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the invention. . Further, not only the image forming apparatus but also a cleaning apparatus applicable to it functions as a part of the present invention. Further, the second cleaning member may be composed of a roller or a brush other than the scraper as long as it has a function of removing toner. For example, in the case of a roller or a brush, a difference in toner removal force can be provided by changing the diameter or material.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Original reading apparatus 30Y-30K Image forming part 40 Intermediate transfer part 41 Intermediate transfer belt 43 Belt cleaning apparatus 45 Secondary transfer part 46 Secondary transfer roller 47 Drive roller 48 Drive roller 49 Secondary transfer belt 50 Cleaning apparatus 51 1st cleaning member 51a 1st sheet-like member 51b 1st support member 52 2nd cleaning member 52a 2nd sheet-like member 52b 2nd support member 60 fixing device 70 paper discharge reversing part 80 re-feeding Part 90 paper feeding part 100 control part

Claims (7)

A transfer member configured to be rotatable in correspondence with the transport direction of the paper and transferring a toner image onto the transported paper;
A first cleaning member that contacts the outer peripheral surface of the transfer member, which is a contact surface with the paper, and removes toner adhering to the outer peripheral surface of the transfer member;
A second member disposed upstream of the first cleaning member in the rotation direction of the transfer member and contacting the outer peripheral surface of the transfer member to remove toner adhering to the outer peripheral surface of the transfer member; A cleaning member;
A transport unit having a plurality of transport members for transporting paper according to each rotation;
The second cleaning member has a difference in toner removal force with respect to the transfer member with respect to the paper width direction orthogonal to the paper transport direction, and the second cleaning member has a first region corresponding to the transport member. In the image forming apparatus, the toner removal force is set to be smaller in the second region that does not correspond to the conveying member. A transfer member configured to be rotatable in correspondence with the transport direction of the paper and transferring a toner image onto the transported paper;
A first cleaning member that contacts the outer peripheral surface of the transfer member, which is a contact surface with the paper, and removes toner adhering to the outer peripheral surface of the transfer member;
A second member disposed upstream of the first cleaning member in the rotation direction of the transfer member and contacting the outer peripheral surface of the transfer member to remove toner adhering to the outer peripheral surface of the transfer member; A cleaning member,
The second cleaning member is a scraper including a resin sheet-like member and a support member that supports the sheet-like member, and the free end side of the sheet-like member is disposed on the outer peripheral surface of the transfer member. An image forming apparatus, characterized in that a difference is provided in toner removal force with respect to the transfer member with respect to a paper width direction that is arranged so as to be pressed against and perpendicular to a paper conveyance direction.   The second cleaning member is arranged so that an extending direction of the sheet-like member from a fixed end to a free end is opposed to a rotation direction of the transfer member. Image forming apparatus.   The second cleaning member provides a difference in the toner removal force by providing a difference in the length from the edge of the support member to the free end of the sheet-like member. The image forming apparatus according to claim 3.   5. The image formation according to claim 3, wherein the second cleaning member removes the toner, the wax contained in the toner together with the toner, or the wax applied as a release material to the fixing member. apparatus.   6. The transfer member according to claim 3, wherein the transfer member is a secondary transfer member that transfers the toner onto the sheet by being brought into pressure contact with the intermediate transfer member onto which the toner image is transferred from the photosensitive member via the sheet. The image forming apparatus described in any of the above.   6. The transfer member according to claim 3, wherein the transfer member is an intermediate transfer member that transfers the toner image transferred from the photosensitive member to the sheet by pressing the secondary transfer member through the sheet. An image forming apparatus as described above.

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