Image forming apparatus

Abstract

To provide an image forming apparatus that can prevent deterioration due to wear while improving cleanability of a conveying body, compared to a case where on a contact surface between a conveying body including a plurality of grooves in a circumferential direction and a cleaning member including unevenness parts, the grooves and the unevenness parts do not intersect each other.SOLUTION: An image forming apparatus has: a secondary transfer belt 36 that moves in a circumferential direction, forms a transfer nip while conveying a recording medium P with an intermediate transfer belt 31 on which a toner image is held, and transfers the toner image to the recording medium P, the secondary transfer belt 36 including a plurality of grooves 102 along the circumferential direction; and a cleaning brush 61 that cleans a surface of the secondary transfer belt 36, recovers an attachment, and includes, on a contact surface with the secondary transfer belt 36, a plurality of unevenness parts 80 extending in a direction intersecting the grooves 102.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to an image forming apparatus. [Background technology]

[0002] The following Patent Document 1 describes an endless transfer belt for holding a developer image, which includes a base layer, an elastic layer including an elastic material and a filler dispersed within the elastic material, laminated on the outside of the base layer, and a surface layer laminated on the outside of the elastic layer, and when the ten-point average roughness of the surface of the surface layer is represented by Rz and the static friction coefficient of the surface of the surface layer is represented by μs, 0 . 0 5 [ μ m ] ≦ R z ≦ 1 . 2 1 [ μ m ] 0.1≦μs≦1.0 A transfer belt that satisfies the above requirements is disclosed.

[0003] The following Patent Document 2 discloses an image forming apparatus including an endless belt as a toner image carrier that carries a toner image, a belt tensioning means consisting of a plurality of rolls including a drive roll for tensioning and transporting the endless belt, and a cleaning member that collects residual toner on the endless belt with at least one of the bridging rolls as an opposing roll, the image forming apparatus being equipped with the endless belt, characterized in that the surface of the endless belt has abrasive marks in the circumferential direction.

[0004] Patent Document 3 listed below discloses an endless belt that is stretched around a plurality of rollers and has grooves on its outer circumferential surface that extend in the endless longitudinal direction. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-174757 A [Patent Document 2] JP 2010-271380 A [Patent Document 3] JP 2005-082327 A Summary of the Invention [Problem to be solved by the invention]

[0006] The present disclosure aims to provide an image forming device that can improve the cleaning ability of a conveying body while suppressing deterioration due to wear at the contact surface between a conveying body having multiple grooves in the circumferential direction and a cleaning member having an uneven portion, compared to a case where the grooves and the uneven portion do not intersect. [Means for solving the problem]

[0007] The image forming apparatus according to the first aspect is a transport body that moves in a circumferential direction and transports a medium between itself and an image holding part on which a toner image is held, forming a transfer nip and transferring the toner image to the medium, the transport body having a plurality of grooves along the circumferential direction, and a cleaning member that cleans the surface of the transport body, collects any adhering matter, and has a plurality of uneven portions on its contact surface with the transport body that extend in a direction intersecting the grooves.

[0008] An image forming apparatus according to a second aspect is the image forming apparatus according to the first aspect, wherein the angle at which the uneven portion intersects with the groove at the contact portion where the cleaning member contacts the surface of the transport body is 45 degrees or less.

[0009] An image forming apparatus according to a third aspect is the image forming apparatus according to the first aspect, wherein a difference in height between the projections and recesses of the cleaning member is 100 μm or more and 1 mm or less.

[0010] An image forming apparatus according to a fourth aspect is the image forming apparatus according to the third aspect, wherein the cleaning member is pressed into the conveying body, and the amount of pressing is greater than an upper limit of the height difference.

[0011] An image forming apparatus according to a fifth aspect is the image forming apparatus according to the first aspect, wherein the cleaning member is a rotating member that rotates while contacting the surface of the transport body, and the uneven portion is formed in a spiral shape on the circumferential surface.

[0012] An image forming apparatus according to a sixth aspect is the image forming apparatus according to the fifth aspect, wherein the cleaning member is a brush member having brush bristles on the surface of a cylindrical portion that contact the surface of the transport body, and the uneven portion is formed in a spiral shape by the length of the brush bristles.

[0013] An image forming apparatus according to a seventh aspect is the image forming apparatus according to the fifth aspect, wherein the cleaning member is a cylindrical member having an elastic layer that contacts the surface of the transport body, and the uneven portion is formed in a spiral shape on the elastic layer.

[0014] The image forming apparatus according to an eighth aspect is the image forming apparatus according to the first aspect, further comprising a viscoelastic layer on the surface of the transport body, the viscoelastic layer having a ten-point height deviation Rz of 1 μm or more and 10 μm or less.

[0015] The image forming apparatus according to a ninth aspect is the image forming apparatus according to the first aspect, further comprising a viscoelastic layer on the surface of the transport body, and an aspect ratio Str of the surface texture of the viscoelastic layer is smaller than 0.5.

[0016] An image forming apparatus according to a tenth aspect is the image forming apparatus according to the first aspect, wherein the cleaning member is divided into three or more parts along the width direction of the transport body, and the spacing between the protrusions and recesses of the divided parts of the cleaning member that contact both ends of the transport body in the width direction is smaller than the spacing between the protrusions and recesses of the divided parts of the cleaning member that contact the inside of both ends of the transport body in the width direction. Effect of the Invention

[0017] According to the image forming device of the first aspect, the contact surface between the conveying body having a plurality of grooves in the circumferential direction and the cleaning member having an uneven portion can improve the cleaning ability of the conveying body while suppressing deterioration due to wear, compared to a case where the grooves and the uneven portion do not intersect.

[0018] According to the image forming device of the second aspect, the cleaning performance of the conveying body can be improved while suppressing deterioration due to wear, compared to when the angle at which the uneven portion of the cleaning member and the groove of the conveying body intersect is greater than 45 degrees.

[0019] According to the image forming apparatus of the third aspect, toner is prevented from passing through the contact area between the cleaning member and the conveying body, compared to when the difference in height of the uneven portion of the cleaning member is greater than 1 mm. Also, compared to when the difference in maximum height of the uneven portion of the cleaning member is less than 100 μm, the cleaning performance of the conveying body can be improved while deterioration due to wear can be suppressed.

[0020] According to the image forming apparatus of the fourth aspect, it is possible to improve the cleaning performance of the conveying body and suppress deterioration due to wear, compared to when the amount of penetration of the cleaning member is smaller than the upper limit of the height difference.

[0021] According to the image forming apparatus of the fifth aspect, the cleaning performance of the conveying body can be improved and deterioration due to wear can be suppressed, compared to when the cleaning member is formed of a non-rotating member.

[0022] According to the image forming apparatus of the sixth aspect, toner is prevented from passing through the contact area between the cleaning member and the conveying body, as compared to when the cleaning member has an uneven portion formed of resin.

[0023] According to the image forming apparatus of the seventh aspect, the cleaning member is easier to manufacture than when the unevenness is formed on the cleaning member by brush bristles.

[0024] According to the image forming apparatus of the eighth aspect, the toner is prevented from passing through the cleaning member at the contact portion with the cleaning member, compared to when the ten-point mean roughness Rz of the surface of the conveying body is greater than 10 μm. Also, compared to when the ten-point mean roughness Rz of the surface of the conveying body is less than 1 μm, the cleaning ability of the conveying body can be improved and deterioration due to wear can be suppressed.

[0025] According to the image forming apparatus of the ninth aspect, the cleanability of the transport body can be improved and deterioration due to wear can be suppressed, compared to when the aspect ratio Str of the surface texture of the transport body is 0.5 or more.

[0026] According to the image forming apparatus of the tenth aspect, the removal performance at both widthwise ends of the transport body can be maintained even if the cleaning member is bent, etc., compared to a case in which the spacing between the concaves and convexes of the divided part of the cleaning member that contacts both widthwise ends of the transport body is equivalent to the spacing between the concaves and convexes of the divided part of the cleaning member that contacts the widthwise center of the transport body. [Brief description of the drawings]

[0027] [Figure 1] 1 is a schematic diagram showing a configuration of an image forming apparatus according to a first embodiment, as viewed from the front side. [Diagram 2] 2 is a schematic configuration diagram showing a cleaning device for a secondary transfer belt used in the image forming apparatus according to the first embodiment. FIG. [Diagram 3] 5 is a schematic diagram illustrating a state in which a cleaning brush of a cleaning device is in contact with a secondary transfer belt. FIG. [Figure 4] FIG. 2A is a schematic side view showing the cleaning brush, and FIG. 2B is a partial cross-sectional view showing a state in which a part of the cleaning brush is cut along the axial direction. [Diagram 5] FIG. 1A is a schematic diagram showing a contact portion between a cleaning brush and a secondary transfer belt, and FIG. 1B is a diagram showing a schematic view of the direction of the uneven portion of the cleaning brush and the direction of the grooves of the belt member. [Figure 6] 13 is a schematic diagram illustrating a state in which a cleaning brush of a cleaning device used in an image forming apparatus according to a second embodiment is in contact with a secondary transfer belt. FIG. [Figure 7] 13 is a schematic diagram showing a contact portion between a cleaning brush and a secondary transfer belt used in an image forming apparatus according to a second embodiment. FIG. [Figure 8] FIG. 11 is a schematic configuration diagram showing a cleaning device for a secondary transfer belt used in an image forming apparatus according to a third embodiment. [Figure 9] 2A and 2B are a side view and an enlarged side view showing a part of the cleaning roll of the cleaning device. [Figure 10] FIG. 4 is a partial cross-sectional view showing a state in which a part of the cleaning roll is cut along the axial direction. [Figure 11] FIG. 13 is a schematic configuration diagram showing a cleaning brush of a cleaning device used in an image forming apparatus according to a fourth embodiment. [Figure 12] (A) is a diagram showing a schematic diagram of the direction of the unevenness of the dividing portion at both ends of the secondary transfer belt in the width direction and the direction of the grooves of the secondary transfer belt, and (B) is a diagram showing a schematic diagram of the direction of the unevenness of the dividing portion at the center of the secondary transfer belt in the width direction and the direction of the grooves of the secondary transfer belt. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] An example of an embodiment of the present invention will be described below with reference to the drawings. In each drawing, an arrow H indicates the vertical direction, and an arrow W indicates the horizontal direction, ie, the width direction of the device.

[0029] [First embodiment] The image forming apparatus according to the first embodiment will be described below.

[0030] <Configuration of Image Forming Apparatus> 1 is a schematic diagram showing the configuration of an image forming apparatus 10 as seen from the front side. As shown in this figure, the image forming apparatus 10 has an image forming section 12 that forms an image on a recording medium P such as paper by electrophotography, a conveying device 50 that conveys the recording medium P, and a control section 70 that controls the operation of each section of the image forming apparatus 10. The recording medium P is an example of a medium.

[0031] (Transportation device) 1, the transport device 50 has a container 51 that stores the recording medium P, and a plurality of transport rolls 52 that transport the recording medium P from the container 51 to a secondary transfer position NT. The transport device 50 further has a plurality of transport belts 58 that transport the recording medium P from the secondary transfer position NT to the fixing device 40, and a transport belt 54 that transports the recording medium P from the fixing device 40 to a discharge section (not shown) for the recording medium P.

[0032] (Image forming section) The image forming unit 12 has a toner image forming unit 20 that forms a toner image, a transfer device 30 that transfers the toner image formed in the toner image forming unit 20 to a recording medium P, and a fixing device 40 that heats and pressurizes the toner image transferred to the recording medium P to fix it to the recording medium P.

[0033] A plurality of toner image forming units 20 are provided so as to form toner images for each color. In this embodiment, toner image forming units 20 for a total of four colors, yellow (Y), magenta (M), cyan (C), and black (K), are provided. The toner image forming units 20 for each color are arranged in the order of yellow (Y), magenta (M), cyan (C), and black (K) from the upstream side to the downstream side in the transport direction of an intermediate transfer belt 31 described later.

[0034] In Fig. 1, (Y), (M), (C), and (K) indicate components corresponding to the above-mentioned respective colors. In the explanation of this specification, the parentheses of (Y), (M), (C), and (K) may be omitted and the components may be written as Y, M, C, and K.

[0035] [Toner image forming section] The toner image forming units 20 of each color are basically configured in the same manner except for the toner used. In the following description, when it is not necessary to distinguish between the colors, (Y), (M), (C), and (K) are omitted and only the reference numerals of each member are described. Specifically, the toner image forming units 20 of each color have a photoconductor drum 21 that rotates in a clockwise direction, a charger 22 that charges the photoconductor drum 21, and an exposure device 23 that exposes the photoconductor drum 21 charged by the charger 22 to form an electrostatic latent image on the photoconductor drum 21. Furthermore, the toner image forming units 20 of each color have a developing device 24 that develops the electrostatic latent image formed on the photoconductor drum 21 by the exposure device 23 to form a toner image, and a blade 25 that removes the toner remaining on the surface of the photoconductor drum 21 after the toner image is transferred to the transfer device 30.

[0036] The charger 22 charges the surface (photosensitive layer) of the photoconductor drum 21 to a negative polarity, for example. The negatively charged surface of the photoconductor drum 21 has a positive polarity at a portion irradiated with exposure light L by the exposure device 23, and an electrostatic latent image is formed on the surface of the photoconductor drum 21. Then, the toner that has been frictionally charged to a negative polarity in the developing device 24 adheres to the electrostatic latent image that has a positive polarity, and the electrostatic latent image is developed. In this manner, a toner image is formed on the surface (outer peripheral surface) of the photoconductor drum 21. The blade 25 comes into contact with the surface of the photoconductor drum 21 and scrapes off the toner remaining on the surface of the photoconductor drum 21.

[0037] [Transfer device] The transfer device 30 performs primary transfer of the toner images of the photoconductor drums 21 of each color in a superimposed manner onto the intermediate transfer belt 31, and performs secondary transfer of the superimposed toner images onto the recording medium P at a secondary transfer position NT (an example of a nip). Specifically, the transfer device 30 includes the intermediate transfer belt 31, a primary transfer roll 33, a secondary transfer belt 36, a cleaning device 60 for the secondary transfer belt 36, and a cleaning device 35 for the intermediate transfer belt 31. The secondary transfer belt 36 is an example of a conveying body that forms a transfer nip while conveying the recording medium P between the secondary transfer belt 36 and the intermediate transfer belt 31. Furthermore, the secondary transfer belt 36 can also be said to be an example of a transfer body that transfers the toner images held on the intermediate transfer belt 31 onto the recording medium P.

[0038] [Intermediate transfer belt] As shown in Fig. 1, the intermediate transfer belt 31 is endless and is wound around a plurality of rolls 32 to determine its position. In this embodiment, the intermediate transfer belt 31 is oriented in the shape of an inverted obtuse triangle that is long in the width direction of the device when viewed from the front. Of the plurality of rolls 32, roll 32D shown in Fig. 1 functions as a drive roll that rotates the intermediate transfer belt 31 in the direction of arrow A by the power of a motor (not shown). By rotating in the direction of arrow A, the intermediate transfer belt 31 transports the primarily transferred image to a secondary transfer position NT.

[0039] 1 functions as a tension applying roll that applies tension to the intermediate transfer belt 31. Of the multiple rolls 32, roll 32B shown in FIG. 1 functions as an opposing roll for the secondary transfer roll 34. The apex of the lower end side forming the obtuse angle of the intermediate transfer belt 31, which is oriented in an inverted obtuse triangle shape as described above, is wound around the opposing roll 32B. This intermediate transfer belt 31 contacts the photoconductor drums 21 of each color from below at its upper side extending in the device width direction in the above-described orientation.

[0040] [Primary transfer roll] The primary transfer rolls 33 are rolls that transfer the toner images on the respective photoconductor drums 21 to the intermediate transfer belt 31, and are disposed inside the intermediate transfer belt 31. Each primary transfer roll 33 is disposed facing the photoconductor drum 21 of the corresponding color across the intermediate transfer belt 31. A primary transfer voltage having a polarity opposite to that of the toner polarity is applied to the primary transfer rolls 33 by a power supply unit (not shown). By applying this primary transfer voltage, the toner image formed on the photoconductor drum 21 is transferred to the intermediate transfer belt 31 at a primary transfer position T between the photoconductor drum 21 and the primary transfer rolls 33.

[0041] [Secondary transfer belt] The secondary transfer belt 36 is a belt that transfers the toner image superimposed on the intermediate transfer belt 31 onto the recording medium P. As shown in FIG. 2, the secondary transfer belt 36 is endless and is wound around the secondary transfer roll 34 and the driven roll 37.

[0042] The secondary transfer roll 34 is disposed so as to sandwich the intermediate transfer belt 31 and the secondary transfer belt 36 between it and the opposing roll 32B, and the secondary transfer belt 36 and the intermediate transfer belt 31 are in contact with each other with a predetermined load. The space between the secondary transfer belt 36 and the intermediate transfer belt 31 in this manner is defined as the secondary transfer position NT. A recording medium P is supplied to this secondary transfer position NT at appropriate times from a container 51 (see FIG. 1). The secondary transfer belt 36 is moved in a circular motion in the direction of the arrow B by the secondary transfer roll 34 being driven to rotate. The configuration of the secondary transfer belt 36 will be described later.

[0043] In the first embodiment, when the toner image on the intermediate transfer belt 31 is transferred to the recording medium P, a negative voltage is applied to the opposing roll 32B by the power supply unit 39 (see FIG. 1). This generates a potential difference between the opposing roll 32B and the secondary transfer roll 34. That is, by applying a negative voltage to the opposing roll 32B, a secondary transfer voltage (positive voltage) of the opposite polarity to the toner polarity is indirectly applied to the secondary transfer roll 34 that serves as the opposing electrode of the opposing roll 32B. This causes the negative toner image to be transferred from the intermediate transfer belt 31 to the recording medium P that passes through the secondary transfer position NT.

[0044] On the other hand, when the toner of the intermediate transfer belt 31 is to be held on the intermediate transfer belt 31 when the toner passes through the secondary transfer position NT, a voltage of positive polarity is applied to the opposing roll 32B by the power supply unit 39. This generates a potential difference between the opposing roll 32B and the secondary transfer roll 34. That is, by applying a voltage of positive polarity to the opposing roll 32B, a non-transfer voltage (voltage of negative polarity) of the same polarity as the toner polarity is indirectly applied to the secondary transfer roll 34, which is the opposing electrode of the opposing roll 32B. As a result, the toner passing through the secondary transfer position NT is held on the intermediate transfer belt 31 by receiving a repulsive force from the secondary transfer roll 34. For example, when a patch (detection image) of toner is formed on the intermediate transfer belt 31 to detect image density or color shift, the patch on the intermediate transfer belt 31 is held on the intermediate transfer belt 31 when the patch passes through the secondary transfer position NT. Reference numeral 49 in FIG. 1 denotes a detection unit that detects image density or color shift of the patch.

[0045] [Intermediate transfer belt cleaning device] 1, the cleaning device 35 is disposed downstream of the secondary transfer position NT and upstream of the primary transfer position T(Y) in the rotation direction of the intermediate transfer belt 31. The cleaning device 35 includes a blade 351 that scrapes off residual toner from the surface of the intermediate transfer belt 31. For example, when a patch is formed on the intermediate transfer belt 31, the patch is scraped off by the blade 351. The cleaning device 35 may include a cleaning brush in addition to the blade 351.

[0046] (Operation of image forming device) Next, the operation of the image forming apparatus 10 will be described.

[0047] When the control unit 70 receives an image formation command (print command), the control unit 70 operates the toner image forming units 20Y to 20K, the transfer device 30, and the fixing device 40 as follows (see FIG. 1).

[0048] In the toner image forming units 20Y to 20K, the photoconductor drums 21 of each color are charged by the chargers 22 while being rotated. The charged photoconductor drums 21 are exposed by the exposure devices 23, and an electrostatic latent image is formed on the surface of each photoconductor drum 21. The electrostatic latent image formed on each photoconductor drum 21 is developed by a developer supplied from the developing device 24. As a result, toner images of yellow (Y), magenta (M), cyan (C), and black (K) are formed on the photoconductor drums 21Y to 21K of each color, respectively.

[0049] The toner images formed on the photoconductor drums 21 are sequentially transferred to the rotating intermediate transfer belt 31 by the primary transfer rolls 33. The toner images transferred to the intermediate transfer belt 31 are transported to a secondary transfer position NT by the rotation of the intermediate transfer belt 31.

[0050] A recording medium P is supplied to this secondary transfer position NT by a transport roll 52 in accordance with the timing of transport of the toner image. When the recording medium P passes through this secondary transfer position NT, a secondary transfer voltage (a voltage of positive polarity) is applied to the secondary transfer roll 34 via the opposing roll 32B. As a result, the toner image is transferred from the intermediate transfer belt 31 to the recording medium P.

[0051] The recording medium P onto which the toner image has been transferred is transported by a transport belt 58 from the secondary transfer position NT to a fixing device 40, where the toner image on the recording medium P is fixed to the recording medium P. Adherents such as toner remaining on the intermediate transfer belt 31 after the secondary transfer are removed by a blade 351 and a cleaning brush of a cleaning device 35.

[0052] (Secondary transfer belt and secondary transfer belt cleaning device) Next, the configurations of the secondary transfer belt 36 and the cleaning device 60 for the secondary transfer belt 36, which are essential parts of the present disclosure, will be described.

[0053] As shown in FIG. 2, the cleaning device 60 has a cleaning brush 61 as an example of a cleaning member that cleans the surface of the secondary transfer belt 36. For example, the cleaning brush 61 comes into contact with the surface of the secondary transfer belt 36 and removes toner from the surface of the secondary transfer belt 36. The cleaning brush 61 is an example of a brush member. In the first embodiment, the cleaning brush 61 is a cylindrical roll brush. As an example, the cleaning brush 61 is provided at a portion where the secondary transfer belt 36 is wound around the secondary transfer roll 34. In the following description, "cleaning the surface of the belt" is synonymous with "removing or collecting adhering matter such as toner from the belt."

[0054] In the first embodiment, the cleaning device 60 has a power supply unit 65 that applies a positive bias voltage (cleaning voltage) to a shaft portion 61A (described later) of the cleaning brush 61. As a result, the cleaning brush 61 attracts and cleans the toner on the secondary transfer belt 36 by electrostatic force according to the bias voltage applied from the power supply unit 65.

[0055] The cleaning device 60 also has a cylindrical flicking bar 63 that comes into contact with a brush portion 61B (described later) of the cleaning brush 61 to repel the bristles 61F. Note that the flicking bar 63 is not limited to the flicking bar 63, and may be another member such as a roll-shaped brush, as long as it can remove toner from the cleaning brush 61.

[0056] The cleaning device 60 has a blade 69 located downstream of the cleaning brush 61 in the rotational direction of the secondary transfer belt 36 and upstream of the secondary transfer position NT, which scrapes off residual toner from the surface of the secondary transfer belt 36.

[0057] In addition, the cleaning device 60 has a receiving portion 71 provided between the secondary transfer belt 36 to surround the cleaning brush 61, the flicking bar 63, and the blade 69, and is configured so that the toner removed from the secondary transfer belt 36 falls into the inside of the receiving portion 71.

[0058] [Secondary transfer belt configuration] As shown in Fig. 3, the secondary transfer belt 36 has a plurality of grooves 102 formed along the circumferential direction (see Fig. 5). Fig. 3 shows an enlarged area 100A of a portion of the outer circumferential surface of the secondary transfer belt 36, and the plurality of grooves 102 are provided in the enlarged area 100A. In Fig. 3, the exact positional relationship is not shown to avoid making the configuration difficult to understand, but the plurality of grooves 102 are formed along the circumferential direction of the secondary transfer belt 36, and thus the plurality of grooves 102 are disposed at equal intervals in the width direction of the secondary transfer belt 36.

[0059] The secondary transfer belt 36 has a viscoelastic layer 101 on its surface. Although not shown in the drawings, the secondary transfer belt 36 may have a configuration in which the viscoelastic layer 101 is formed on the surface of an endless base material. In the first embodiment, a plurality of grooves 102 are formed on the surface of the viscoelastic layer 101 along the circumferential direction. As an example, the plurality of grooves 102 are formed substantially continuously along the circumferential direction.

[0060] The ten-point average roughness Rz of the surface of the viscoelastic layer 101 is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 8 μm or less, and even more preferably 3 μm or more and 6 μm or less. Here, the ten-point average roughness Rz is the ten-point average roughness Rz measured in accordance with JIS B 0601:1994. The ten-point average roughness Rz is measured using a contact surface roughness measuring device (Surfcom 570A, manufactured by Tokyo Seimitsu Co., Ltd.) in an environment of 23°C and 55% RH. The measurement distance is 2.5 mm, and a contact needle with a diamond tip (5 μmR, 90° cone) is used for the measurement, and the average value is calculated. In the case of the axial direction, the ten-point average roughness Rz is, for example, the average value of the values ​​obtained by dividing the axial direction into six equal parts and measuring the center part of the six equal parts. In the case of the circumferential direction, for example, the ten-point average roughness Rz is the average value of values ​​measured at the center positions of the axial center portion, which are divided into six equal parts in the circumferential direction.

[0061] The aspect ratio Str of the surface texture of the viscoelastic layer 101 of the secondary transfer belt 36 is preferably smaller than 0.5, more preferably smaller than 0.45, and even more preferably smaller than 0.4. Here, the aspect ratio Str of the surface texture is a parameter of the surface texture defined in ISO25178, and indicates the isotropy or anisotropy of the surface texture. The aspect ratio Str of the surface texture is a value between 0 and 1, and when it is close to 0, it indicates that there are streaks, and when it is close to 1, it indicates that the surface is independent of the direction. The maximum height of the viscoelastic layer 101 on the surface is set based on the average particle size of the toner used in the image forming apparatus 10. The measuring device and measuring conditions are as follows. Measurement equipment: Keyence VK-X3000 shape analysis laser microscope Measurement range: 1.06mm x 1.42mm Measurement conditions: Gaussian filter used S filter: Not used L filter: 0.1 mm

[0062] The interval between the plurality of grooves 102 (ie, the pitch between the plurality of grooves 102) is preferably 60 μm or less, more preferably 50 μm or less, and even more preferably 45 μm or less.

[0063] [Cleaning brush configuration] 2, the cleaning brush 61 has a metal shaft portion 61A and a synthetic resin brush portion 61B provided around the entire outer periphery of the shaft portion 61A. In the brush portion 61B, a large number of bristles 61F extend radially (outward in the radial direction) from the shaft portion 61A. The shaft portion 61A is an example of a cylindrical portion, and the bristles 61F are an example of brush bristles.

[0064] The cleaning brush 61 rotates when the shaft 61A is rotated by a rotation drive device 67 such as a motor. The cleaning brush 61 is an example of a rotating member, and rotates while contacting the surface of the secondary transfer belt 36. As an example, the cleaning brush 61 rotates in the same direction as the rotation direction of the secondary transfer belt 36 (clockwise in FIG. 2). In other words, at the contact portion between the cleaning brush 61 and the secondary transfer belt 36, the cleaning brush 61 rotates in the opposite direction to the rotation direction of the secondary transfer belt 36.

[0065] The rotary drive device 67 may rotate the cleaning brush 61 in a direction opposite to the rotation direction of the secondary transfer belt 36 (counterclockwise in FIG. 2). When the cleaning brush 61 rotates in a direction opposite to the rotation direction of the secondary transfer belt 36, it is preferable that the cleaning brush 61 rotates at a peripheral speed different from that of the secondary transfer belt 36, for example.

[0066] 3 and 4(A) and (B), the cleaning brush 61 has a plurality of projections and recesses 80 extending in a direction intersecting the grooves 102 on the contact surface with the secondary transfer belt 36. The projections and recesses 80 are formed by changing the length of the bristles 61F arranged in the radial direction, and are configured to have projections 80A with long bristles 61F and recesses 80B with short bristles 61F. The plurality of projections and recesses 80 are configured by alternately arranging the projections 80A and recesses 80B along the axial direction of the cleaning brush 61.

[0067] The height difference of the unevenness 80 in the cleaning brush 61, ie, the height difference between the projections 80A and the recesses 80B, is preferably 100 μm to 1 mm, more preferably 200 μm to 800 μm, and even more preferably 300 μm to 500 μm.

[0068] As an example, the cleaning brush 61 has a spirally uneven portion 80 formed on its circumferential surface (see FIG. 4A). In the first embodiment, the cleaning brush 61 has the spirally uneven portion 80 formed by changing the length of the bristles 61F (see FIGS. 4A and 4B). As a result, the cleaning brush 61 has a plurality of uneven portions 80 formed along the axial direction on its contact surface with the secondary transfer belt 36.

[0069] 5(A), at the contact portion where the cleaning brush 61 contacts the surface of the secondary transfer belt 36, the uneven portion 80 of the cleaning brush 61 intersects with the grooves 102 of the secondary transfer belt 36. As shown in Fig. 5(B), at the contact portion between the cleaning brush 61 and the secondary transfer belt 36 in a plan view, a direction 81 of the uneven portion 80 of the cleaning brush 61 intersects with a direction 103 of the grooves 102 of the secondary transfer belt 36 at an angle θ.

[0070] At the contact portion where the cleaning brush 61 contacts the surface of the secondary transfer belt 36, the angle θ at which the uneven portion 80 intersects with the groove 102 is preferably 45 degrees or less, more preferably 43 degrees or less, and even more preferably 41 degrees or less. For example, at the contact portion where the cleaning brush 61 contacts with the surface of the secondary transfer belt 36, the angle θ at which the uneven portion 80 intersects with the groove 102 is 40 degrees.

[0071] As an example, the brush portion 61B of the cleaning brush 61 is in contact with the secondary transfer belt 36 while being dug into the secondary transfer belt 36, and the degree of dug-in of the brush portion 61B is greater than the upper limit of the difference in height of the uneven portion 80, i.e., the difference in height between the convex portion 80A and the concave portion 80B. As a result, both the convex portion 80A and the concave portion 80B of the cleaning brush 61 are in contact with the surface of the secondary transfer belt 36.

[0072] (Operation of the First Embodiment) Next, the operation of the first embodiment will be described.

[0073] In the image forming apparatus 10, the secondary transfer belt 36 and the intermediate transfer belt 31 are in contact with each other under a predetermined load, so that some of the toner held on the intermediate transfer belt 31 may be transferred to the secondary transfer belt 36, through which the recording medium P does not pass. In particular, when a patch of toner is formed on the surface of the intermediate transfer belt 31 in order to adjust image density or color shift, some of the toner of the patch may be transferred to the secondary transfer belt 36 even if a voltage of the opposite polarity to that during transfer is applied from the power supply unit 39. This causes the toner to adhere to the surface of the secondary transfer belt 36.

[0074] The toner adhering to the secondary transfer belt 36 is transported to the cleaning device 60 as the secondary transfer belt 36 rotates. The cleaning device 60 includes a cleaning brush 61 that comes into contact with the surface of the secondary transfer belt 36, and the cleaning brush 61 cleans the surface of the secondary transfer belt 36, thereby removing (i.e., collecting) the toner and other adhering matter on the surface of the secondary transfer belt 36.

[0075] The secondary transfer belt 36 has a plurality of grooves 102 along the circumferential direction. The cleaning brush 61 has a plurality of uneven portions 80 on the contact surface with the secondary transfer belt 36, which extend in a direction intersecting the grooves 102. As a result, at the contact portion where the cleaning brush 61 contacts the surface of the secondary transfer belt 36, the plurality of grooves 102 of the secondary transfer belt 36 and the plurality of uneven portions 80 of the cleaning brush 61 intersect with each other. The cleaning brush 61 is displaced in the axial direction by the rotation of the plurality of uneven portions 80, and rotates intersecting with the plurality of grooves 102 of the secondary transfer belt 36, so that the portion with high contact pressure and the portion with low contact pressure move in the axial direction with the rotation of the cleaning brush 61. That is, the contact pressure of the cleaning brush 61 with the secondary transfer belt 36 repeatedly increases and decreases in the axial direction. As a result, it is possible to suppress adhesions such as toner from slipping through the contact portion between the cleaning brush 61 and the secondary transfer belt 36, and to reduce excessive frictional resistance, thereby obtaining excellent durability characteristics.

[0076] Generally, in a configuration in which a cleaning member such as a cleaning brush contacts a secondary transfer belt, if the diameter of the cleaning member is equal along the axial direction, the shape of the concave portion where the cleaning member contacts the secondary transfer belt changes, and the adhesion decreases, which may cause toner and other adherent matter to slip through. Also, the cleaning performance and durability may decrease due to friction between the cleaning member and the secondary transfer belt.

[0077] In contrast, in the image forming apparatus 10 of the first embodiment, at the contact portion between the cleaning brush 61 and the secondary transfer belt 36, the multiple grooves 102 of the secondary transfer belt 36 and the multiple uneven portions 80 of the cleaning brush 61 intersect with each other. This results in a configuration in which the contact pressure of the cleaning brush 61 with the secondary transfer belt 36 repeatedly increases and decreases in the axial direction as the cleaning brush 61 rotates. This prevents adherent matter such as toner from slipping through the contact portion between the cleaning brush 61 and the secondary transfer belt 36, and reduces excessive frictional resistance.

[0078] Therefore, in the image forming device 10, the contact surface between the transport body having multiple grooves in the circumferential direction and the cleaning member having uneven portions can improve the cleaning ability of the secondary transfer belt 36 while suppressing deterioration due to wear, compared to a case where the grooves and the uneven portions do not intersect.

[0079] Furthermore, in the image forming apparatus 10, the angle θ at which the uneven portion 80 and the groove 102 intersect at the contact portion where the cleaning brush 61 contacts the surface of the secondary transfer belt 36 is 45 degrees or less. This tends to result in a configuration in which the contact pressure of the cleaning brush 61 on the secondary transfer belt 36 repeatedly increases and decreases in the axial direction at the contact portion between the cleaning brush 61 and the secondary transfer belt 36. Therefore, in the image forming apparatus 10, it is possible to improve the cleaning performance of the secondary transfer belt 36 while suppressing deterioration due to wear, compared to a case in which the angle at which the uneven portion of the cleaning member intersects with the groove of the secondary transfer belt is greater than 45 degrees.

[0080] In the image forming apparatus 10, the height difference of the uneven portion 80 in the cleaning brush 61 is 100 μm or more and 1 mm or less. Therefore, in the image forming apparatus 10, toner is prevented from passing through the contact portion between the cleaning brush 61 and the secondary transfer belt 36, compared to when the difference in maximum height of the uneven portion of the cleaning member is greater than 1 mm. In addition, compared to when the difference in maximum height of the uneven portion of the cleaning member is less than 100 μm, the cleaning performance of the secondary transfer belt 36 can be improved while deterioration due to wear can be suppressed.

[0081] Furthermore, in the image forming apparatus 10, the brush portion 61B of the cleaning brush 61 is in contact with the secondary transfer belt 36 while being dug into, and the amount of dug-in of the brush portion 61B is greater than the upper limit of the height difference of the uneven portion 80, i.e., the height difference between the convex portion 80A and the concave portion 80B. As a result, both the convex portion 80A and the concave portion 80B of the cleaning brush 61 are in contact with the secondary transfer belt 36. Therefore, in the image forming apparatus 10, it is possible to improve the cleaning performance of the secondary transfer belt 36 while suppressing deterioration due to wear, compared to a case in which the amount of dug-in of the cleaning brush is smaller than the upper limit of the height difference.

[0082] Moreover, in the image forming apparatus 10, the cleaning brush 61 is a rotating member that rotates while contacting the surface of the secondary transfer belt 36, and has a spirally uneven portion 80 formed on its circumferential surface. As a result, the spirally uneven portion 80 of the cleaning brush 61 rotates while intersecting with the multiple grooves 102 of the secondary transfer belt 36, and as the cleaning brush 61 rotates, a portion with high contact pressure and a portion with low contact pressure with the secondary transfer belt 36 move in the axial direction. Therefore, in the image forming apparatus 10, the cleaning ability of the secondary transfer belt 36 can be improved while deterioration due to wear can be suppressed, compared to a case in which the cleaning member is formed of a non-rotating member.

[0083] Furthermore, in the image forming apparatus 10, the cleaning brush 61 is provided with bristles 61F on the surface of the shaft 61A that come into contact with the surface of the secondary transfer belt 36, and the length of the bristles 61F forms a spiral uneven portion 80. This makes it easier for the bristles 61F of the cleaning brush 61 to come into contact with toner and other deposits on the surface of the secondary transfer belt 36 as the cleaning brush 61 rotates. Therefore, in the image forming apparatus 10, toner is prevented from passing through the contact portion of the cleaning brush 61 with the secondary transfer belt 36, compared to when uneven portions are formed on the cleaning member by resin.

[0084] Moreover, in the image forming apparatus 10, the surface of the secondary transfer belt 36 has a viscoelastic layer 101, and the viscoelastic layer 101 has a ten-point mean roughness Rz of 1 μm or more and 10 μm or less. Therefore, in the image forming apparatus 10, the toner is prevented from passing through the contact portion between the secondary transfer belt 36 and the cleaning brush 61, compared to when the ten-point mean roughness Rz of the surface of the secondary transfer belt is greater than 10 μm. Also, compared to when the ten-point mean roughness Rz of the surface of the secondary transfer belt is less than 1 μm, the cleaning ability of the secondary transfer belt 36 can be improved while deterioration due to wear can be suppressed.

[0085] In addition, the image forming apparatus 10 has a viscoelastic layer 101 on the surface of the secondary transfer belt 36, and the aspect ratio Str of the surface texture of the viscoelastic layer 101 is smaller than 0.5. When the aspect ratio Str of the surface texture of the viscoelastic layer 101 is smaller than 0.5, the surface of the viscoelastic layer 101 has a plurality of grooves 102 such as streaks. As the aspect ratio Str of the surface texture of the viscoelastic layer approaches 1, the surface of the viscoelastic layer becomes direction independent. Therefore, in the image forming apparatus 10, the cleaning ability of the secondary transfer belt 36 can be improved while deterioration due to wear can be suppressed, compared to when the aspect ratio Str of the surface texture of the secondary transfer belt is 0.5 or more.

[0086] Second Embodiment Next, an image forming apparatus according to a second embodiment will be described. Note that the same components as those in the first embodiment are given the same reference numerals and the description thereof will be omitted.

[0087] 6 and 7, in a cleaning section by a cleaning device 60 of an image forming apparatus 130 of the second embodiment, the configuration of a secondary transfer belt 132 as an example of a conveying body is different from that of the first embodiment. The secondary transfer belt 132 is endless and has a viscoelastic layer 133 on its surface. In the second embodiment, a plurality of grooves 134 are formed along the circumferential direction on the surface of the viscoelastic layer 133. As an example, the plurality of grooves 134 are discontinuous along the circumferential direction and are formed at intervals in the circumferential direction.

[0088] The ten-point average roughness Rz of the viscoelastic layer 133 is 1 μm or more and 10 μm or less. The aspect ratio Str of the surface texture of the viscoelastic layer 133 is smaller than 0.5.

[0089] 7, the cleaning brush 61 has a plurality of uneven portions 80 extending in a direction intersecting the grooves 134 on the contact surface with the secondary transfer belt 132. As a result, at the contact portion where the cleaning brush 61 comes into contact with the surface of the secondary transfer belt 132, the plurality of grooves 134 of the secondary transfer belt 132 and the plurality of uneven portions 80 of the cleaning brush 61 intersect with each other. Other configurations of the image forming apparatus 130 are similar to those of the image forming apparatus 10 of the first embodiment.

[0090] The image forming apparatus 130 of the second embodiment has a similar configuration to the image forming apparatus 10 of the first embodiment, and can provide similar functions and effects.

[0091] Third Embodiment Next, an image forming apparatus according to a third embodiment will be described. Note that the same components as those in the first and second embodiments are given the same reference numerals and the description thereof will be omitted.

[0092] As shown in FIG. 8, in a cleaning device 151 of an image forming apparatus 150 of the third embodiment, the configuration of a cleaning roll 152 as an example of a cleaning member is different from that of the first embodiment. The cleaning roll 152 includes a shaft portion 152A and an elastic layer 152B provided on the outer circumferential surface of the shaft portion 152A. The cleaning roll 152 is an example of a cylindrical member. The elastic layer 152B is in contact with the secondary transfer belt 36 wound around the secondary transfer roll 34 in a concave elastically deformed state. The cleaning roll 152 is an example of a rotating member, and rotates while in contact with the surface of the secondary transfer belt 36.

[0093] As an example, the elastic layer 152B is formed of a conductive rubber material, and a positive bias voltage (cleaning voltage) is applied via a power supply roll 160 that contacts the outer peripheral surface of the elastic layer 152B.

[0094] 9, the cleaning roll 152 has a plurality of uneven portions 154 extending in a direction intersecting the grooves 102 (see FIG. 3) on the contact surface with the secondary transfer belt 36. The uneven portions 154 are formed by changing the radial thickness of the elastic layer 152B, so that convex portions 154A having a high radial height of the elastic layer 152B and concave portions 154B having a low radial height of the elastic layer 152B (see FIG. 10). The plurality of uneven portions 154 are configured such that the convex portions 154A and the concave portions 154B are alternately arranged along the axial direction of the cleaning roll 152.

[0095] The height difference of the unevenness 154 in the cleaning roll 152, ie, the height difference between the projections 154A and the recesses 154B, is preferably 100 μm to 1 mm, more preferably 200 μm to 800 μm, and even more preferably 300 μm to 500 μm.

[0096] As an example, a spirally shaped uneven portion 154 is formed on the peripheral surface of the cleaning roll 152, and at the contact portion where the cleaning roll 152 comes into contact with the surface of the secondary transfer belt 36, the uneven portion 154 of the cleaning roll 152 intersects with the groove 102 of the secondary transfer belt 36 (see Figure 3).

[0097] Also, the elastic layer 152B of the cleaning roll 152 bites into the secondary transfer belt 36 (see FIG. 8). The amount of bite of the elastic layer 152B into the secondary transfer belt 36 is greater than the upper limit of the difference in height of the unevenness 154, i.e., the difference in height between the convex portions 154A and the concave portions 154B. This allows both the convex portions 154A and the concave portions 154B of the elastic layer 152B to come into contact with the surface of the secondary transfer belt 36. Other configurations of the image forming apparatus 150 are similar to those of the image forming apparatus 10 of the first embodiment.

[0098] In the image forming apparatus 150 of the third embodiment, in addition to the actions and effects of the same configuration as the image forming apparatus 10 of the first embodiment, the following actions and effects can be obtained.

[0099] In the image forming apparatus 150, the elastic layer 152B of the cleaning roll 152 bites into the secondary transfer belt 36, and the amount of bite of the elastic layer 152B is larger than the upper limit of the height difference of the unevenness portion 154. Therefore, in the image forming apparatus 150, it is possible to improve the cleaning performance of the secondary transfer belt 36 while suppressing deterioration due to wear, compared to a case in which the amount of bite of the cleaning roll is smaller than the upper limit of the height difference.

[0100] Moreover, in the image forming apparatus 150, the cleaning roll 152 is a cylindrical member having an elastic layer 152B that contacts the surface of the secondary transfer belt 36, and the elastic layer 152B is formed with a spirally uneven portion 154. Therefore, in the image forming apparatus 150, the cleaning roll 152 is easier to manufacture than when the uneven portion is formed on the cleaning member by brush bristles.

[0101] [Fourth embodiment] Next, an image forming apparatus according to a fourth embodiment will be described. Note that the same components as those in the first to third embodiments described above are given the same reference numerals and the description thereof will be omitted.

[0102] As shown in FIG. 11, in a cleaning device 171 of an image forming apparatus 170 of the fourth embodiment, the configuration of a cleaning brush 172 as an example of a cleaning member is different from that of the first embodiment. The cleaning brush 172 is formed by dividing it into three or more parts along the width direction of the secondary transfer belt 36. As an example, the cleaning brush 172 has a first divided part 172A, a second divided part 172B, and a third divided part 172C as an example of a divided part divided into three parts. The first divided part 172A and the third divided part 172C are disposed at both ends in the width direction of the secondary transfer belt 36, and the second divided part 172B is disposed inside the both ends in the width direction of the secondary transfer belt 36 (at the center in the width direction of the secondary transfer belt 36 in the fourth embodiment).

[0103] 11 and 12, the first divided portion 172A and the third divided portion 172C are provided with a plurality of uneven portions 174 extending in a direction intersecting the groove 102 on the contact surface with the secondary transfer belt 36. The uneven portions 174 are an example of unevenness, and are provided with recessed portions 174B and protruding portions 174A. The second divided portion 172B is provided with a plurality of uneven portions 176 extending in a direction intersecting the groove 102 on the contact surface with the secondary transfer belt 36. The uneven portions 176 are an example of unevenness, and are provided with recessed portions 176B and protruding portions 176A.

[0104] A distance D1 between the projections and recesses 174 of the first divided portion 172A and the third divided portion 172C is smaller than a distance D2 between the projections and recesses 176 of the second divided portion 172B (see FIG. 12). Other configurations of the image forming apparatus 170 are similar to those of the image forming apparatus 10 of the first embodiment.

[0105] In the image forming apparatus 170 of the fourth embodiment, in addition to the actions and effects of the same configuration as the image forming apparatus 10 of the first embodiment, the following actions and effects can be obtained.

[0106] In the image forming apparatus 170, the cleaning brush 172 is divided into three parts along the width direction of the secondary transfer belt 36. The interval D1 between the uneven parts 174 of the first divided part 172A and the third divided part 172C that contact both ends of the secondary transfer belt 36 in the width direction is smaller than the interval D2 between the uneven parts 176 of the second divided part 172B that contacts the inside of both ends of the secondary transfer belt 36 in the width direction. Therefore, in the image forming apparatus 170, even if the cleaning brush 172 is bent, the removal performance at both ends of the secondary transfer belt 36 in the width direction can be maintained, compared to a case in which the interval between the uneven parts of the divided parts of the cleaning member that contact both ends of the secondary transfer belt in the width direction is equal to the interval between the uneven parts of the divided parts of the cleaning member that contact the center of the secondary transfer belt in the width direction.

[0107] 〔supplementary explanation〕 In the second embodiment, the cleaning brush 61 is in contact with the secondary transfer belt 132, but the present disclosure is not limited to this configuration. For example, a configuration in which the cleaning roll 152 is in contact with the secondary transfer belt 132 may also be used.

[0108] In the fourth embodiment, the cleaning brush 172 is divided into three along the width direction of the secondary transfer belt 36, but the present disclosure is not limited to this configuration. For example, the cleaning roll may be divided into three along the width direction of the secondary transfer belt 36, and the spacing between the projections and recesses of the divided parts of the cleaning roll that contact both ends of the secondary transfer belt 36 in the width direction may be smaller than the spacing between the projections and recesses of the divided parts of the cleaning roll that contact the inside of both ends of the secondary transfer belt 36 in the width direction.

[0109] In the fourth embodiment, the cleaning brush 172 divided into three pieces contacts the secondary transfer belt 36, but the present disclosure is not limited to this configuration. For example, a cleaning member such as a cleaning brush or a cleaning roll may be divided into three or more pieces (for example, four or five) along the width direction of the secondary transfer belt.

[0110] In the first to fourth embodiments, the cleaning brush or cleaning roll rotates while contacting the secondary transfer belt, but the present disclosure is not limited to this configuration. For example, a non-rotating web-like cleaning member may be configured to contact the secondary transfer belt. That is, a configuration may be provided in which a plurality of projections and recesses extend in a direction intersecting with the grooves on the contact surface of the web-like cleaning member with the secondary transfer belt.

[0111] In the first to fourth embodiments, a cleaning member such as a cleaning brush or a cleaning roll contacts the surface of the secondary transfer belt to remove toner and other deposits on the surface of the secondary transfer belt, but the present disclosure is not limited to this configuration. For example, the present disclosure may be applied to a cleaning member of a transfer belt in an image forming apparatus that includes a transfer belt facing a photoreceptor as an example of an image holding unit, conveys a recording medium P between the photoreceptor and the transfer belt, and transfers a toner image on the photoreceptor to the recording medium P. Specifically, the present disclosure may be applied to a cleaning member of the transfer belt, in which a plurality of grooves are formed along the circumferential direction of the transfer belt, and a plurality of uneven portions extending in a direction intersecting the grooves are provided on the contact surface of the cleaning member with the transfer belt. The present disclosure is not limited to a transfer belt, and may be applied to a cleaning member that contacts a roll-shaped transfer body.

[0112] Although the present invention has been described in detail with respect to a specific embodiment, it will be apparent to those skilled in the art that the present invention is not limited to such an embodiment, and that various other embodiments are possible within the scope of the present invention.

[0113] [Additional Notes] Preferred aspects of the present disclosure will be described below.

[0114] (((1))) a conveying body that moves in a circumferential direction and conveys a medium between itself and an image holding part on which a toner image is held, forming a transfer nip and transferring the toner image to the medium, the conveying body having a plurality of grooves along a circumferential direction; a cleaning member that cleans the surface of the conveying body and collects deposits, and that has a plurality of projections and recesses on a surface that comes into contact with the conveying body and extends in a direction intersecting with the grooves; An image forming apparatus comprising:

[0115] (((2))) The image forming apparatus according to (((1))), wherein the angle at which the uneven portion intersects with the groove at a contact portion where the cleaning member comes into contact with the surface of the transport body is 45 degrees or less.

[0116] (((3))) The image forming apparatus according to ((1))) or (((2))), wherein the difference in height of the projections and recesses in the cleaning member is 100 μm or more and 1 mm or less.

[0117] (((4))) The image forming apparatus according to any one of ((1)) to ((3)), wherein the cleaning member is biting into the transport body, and the amount of biting is greater than an upper limit of the height difference.

[0118] (((5))) The cleaning member is a rotating member that rotates while contacting the surface of the transport body, and the uneven portion is formed in a spiral shape on its circumferential surface. An image forming apparatus as described in any one of ((1))) to (((4))).

[0119] (((6))) The cleaning member is a brush member having brush bristles on the surface of a cylindrical portion that contact the surface of the transport body, and the uneven portion is formed in a spiral shape due to the length of the brush bristles (((5))) of the image forming apparatus.

[0120] (((7))) The cleaning member is a cylindrical member having an elastic layer that contacts the surface of the transport body, and the uneven portion is formed in a spiral shape on the elastic layer (((5))).

[0121] (((8))) The image forming apparatus according to any one of ((1))) to (((7))), further comprising a viscoelastic layer on the surface of the transport body, the viscoelastic layer having a ten-point average roughness Rz of 1 μm or more and 10 μm or less.

[0122] (((9))) The image forming apparatus according to any one of ((1)) to ((8))), further comprising a viscoelastic layer on a surface of the transport body, the viscoelastic layer having a surface property aspect ratio Str of less than 0.5.

[0123] (((10))) The cleaning member is divided into three or more parts along the width direction of the conveying body, An image forming apparatus according to any one of ((1)) to (((9))), wherein the spacing between the projections and recesses of the divided portion of the cleaning member that contacts both ends of the transport body in the width direction is smaller than the spacing between the projections and recesses of the divided portion of the cleaning member that contacts the transport body on the inside of both ends of the width direction.

[0124] According to the image forming device described in (((1))), the contact surface between the conveying body having a plurality of grooves in the circumferential direction and the cleaning member having an uneven portion can improve the cleaning ability of the conveying body while suppressing deterioration due to wear, compared to a case where the grooves and the uneven portion do not intersect.

[0125] According to the image forming apparatus described in (((2))), the cleaning ability of the conveying body can be improved while suppressing deterioration due to wear, compared to when the angle at which the uneven portion of the cleaning member and the groove of the conveying body intersect is greater than 45 degrees.

[0126] According to the image forming apparatus described in (((3))), the toner is prevented from passing through the contact area between the cleaning member and the conveying body, compared to when the difference in height of the uneven portion of the cleaning member is greater than 1 mm. Also, compared to when the difference in maximum height of the uneven portion of the cleaning member is less than 100 μm, the cleaning performance of the conveying body can be improved while deterioration due to wear can be suppressed.

[0127] According to the image forming apparatus described in (((4))), the cleaning ability of the conveying body can be improved while suppressing deterioration due to wear, compared to when the amount of penetration of the cleaning member is smaller than the upper limit of the height difference.

[0128] According to the image forming apparatus described in (((5))), the cleaning ability of the conveying body can be improved while suppressing deterioration due to wear, compared to when the cleaning member is formed of a non-rotating member.

[0129] According to the image forming apparatus described in (((6))), toner is prevented from slipping through the cleaning member at the contact portion between the cleaning member and the conveying body, compared to when the cleaning member has an uneven portion formed of resin.

[0130] According to the image forming apparatus described in (((7))), the cleaning member is easier to manufacture than when the cleaning member has projections and recesses formed by brush bristles.

[0131] According to the image forming apparatus described in (((8))), the toner is prevented from passing through the cleaning member at the contact portion with the cleaning member, compared to when the ten-point mean roughness Rz of the surface of the conveying body is greater than 10 μm. Also, compared to when the ten-point mean roughness Rz of the surface of the conveying body is less than 1 μm, the cleaning ability of the conveying body can be improved while suppressing deterioration due to wear.

[0132] According to the image forming apparatus described in (((9))), the cleaning ability of the transport body can be improved while suppressing deterioration due to wear, compared to when the aspect ratio Str of the surface texture of the transport body is 0.5 or more.

[0133] According to the image forming apparatus described in (((10))), the removal performance at both ends of the width direction of the transport body can be maintained even if the cleaning member is deflected, etc., compared to a case in which the spacing between the concaves and convexes of the divided part of the cleaning member that contacts both ends of the transport body in the width direction is equivalent to the spacing between the concaves and convexes of the divided part of the cleaning member that contacts the centre of the width direction of the transport body. [Explanation of symbols]

[0134] 10 Image forming device 31 Intermediate transfer belt (an example of an image carrier) 36 Secondary transfer belt (an example of a transport body) 61 Cleaning brush (an example of a cleaning member, an example of a rotating member, an example of a brush member) 61A Shaft portion (an example of a cylindrical portion) 61F Bristle material (example of brush bristles) 80 Uneven part 101 Viscoelastic layer 102 Groove 130 Image forming device 132 Secondary transfer belt (an example of a transport body) 133 Viscoelastic Layer 134 Groove 150 Image forming device 152 Cleaning roll (an example of a cleaning member, an example of a rotating member, an example of a cylindrical member) 152B Elastic layer 154 Uneven part 170 Image forming device 172 Cleaning brush (an example of a cleaning part, an example of a rotating part) 172A First division part (an example of a division part contacting both ends of the conveying body in the width direction) 172B Second division part (an example of a division part that contacts the inside of both ends of the conveying body in the width direction) 172C Third division section (An example of a division section that contacts both ends of the conveying body in the width direction) 174 Unevenness (an example of unevenness) 176 Unevenness (example of unevenness) 351 Cleaning Blade 351 Blade θ angle D1 Interval D2 interval P Recording medium (example of a medium)

Claims

1. a conveying body that moves in a circumferential direction and conveys a medium between itself and an image holding part on which a toner image is held, forming a transfer nip and transferring the toner image to the medium, the conveying body having a plurality of grooves along a circumferential direction; a cleaning member that cleans the surface of the conveying body and collects deposits, and that has a plurality of projections and recesses on a surface that comes into contact with the conveying body and extends in a direction intersecting with the grooves; An image forming apparatus comprising:

2. 2. The image forming apparatus according to claim 1, wherein the angle at which the uneven portion intersects with the groove at a contact portion of the cleaning member that contacts the surface of the transport body is 45 degrees or less.

3. 2. The image forming apparatus according to claim 1, wherein a difference in height between the projections and recesses of the cleaning member is 100 [mu]m or more and 1 mm or less.

4. The image forming apparatus according to claim 3 , wherein the cleaning member is pressed into the transport body by an amount greater than an upper limit of the height difference.

5. 2. The image forming apparatus according to claim 1, wherein the cleaning member is a rotating member that rotates while contacting the surface of the transport body, and the uneven portion is formed in a spiral shape on a peripheral surface of the cleaning member.

6. 6. The image forming apparatus according to claim 5, wherein the cleaning member is a brush member having brush bristles on a cylindrical surface thereof that contact the surface of the transport body, and the uneven portion is formed in a spiral shape depending on the length of the brush bristles.

7. 6. The image forming apparatus according to claim 5, wherein the cleaning member is a cylindrical member having an elastic layer that contacts the surface of the transport body, and the uneven portion is formed in a spiral shape on the elastic layer.

8. 2. The image forming apparatus according to claim 1, further comprising a viscoelastic layer on a surface of the transport body, the viscoelastic layer having a ten-point average roughness Rz of 1 [mu]m or more and 10 [mu]m or less.

9. 2. The image forming apparatus according to claim 1, further comprising a viscoelastic layer on a surface of the transport body, the viscoelastic layer having a surface property with an aspect ratio Str smaller than 0.

5.

10. The cleaning member is divided into three or more parts along the width direction of the conveying body, 2 . The image forming apparatus according to claim 1 , wherein the spacing between the projections and recesses of the divided portion of the cleaning member that contacts both ends of the transport body in the width direction is smaller than the spacing between the projections and recesses of the divided portion of the cleaning member that contacts the transport body on the inside of both ends of the width direction.

Images