JP2016033535A - Roller support mechanism, roller unit and fixation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a roller support mechanism, roller unit and fixation device that can stably support a rotary roller.SOLUTION: A fixation device 16 comprises: a heating roller 16A; a pressure roller 16B; and a cleaning roller 71 that cleans a surface of the pressure roller 16B. The cleaning roller 71 is supported by a support mechanism 80, which comprises: a support frame 81 made up of a sheet metal; a covering member 82; and a bearing member 83. The covering member 82 is mounted to a support groove 85 of the support frame 81, and a guide groove 83B of the bearing member 83 is slidably attached relative to the covering member 82. In an upper part of the covering member 82, a blockage plate 100 is provided that blocks an aperture part 85C of the support groove 85B.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a roller support mechanism for supporting a rotating roller provided in a fixing device of an image forming apparatus.

  The electrophotographic image forming apparatus includes a fixing device that fixes the toner image transferred to the printing paper on the printing paper. The fixing device includes a heating roller and a pressure roller, and these rollers are rotatably supported while being pressed against each other (see Patent Documents 1 and 2). When printing paper (sheet) is passed through the nip portion between the heating roller and the pressure roller, heat is transmitted from the heating roller at that time, whereby the toner image is melted and printed. The image is fixed on the paper.

  In this type of fixing device, a claw-shaped separation member made of resin is provided on the downstream side in the transport direction of the nip portion in order to prevent printing paper from being wound around the heating roller. . The tip of the separating member is in contact with the heating roller. When the leading edge of the printing paper adhered to the heating roller reaches the contact portion with the separation member, the printing paper is separated from the heating roller by the separation member at the contact portion. When the heating roller is rotated in a state where the separation member is in contact with the heating roller, the separation member is worn by the contact, and shavings are generated. When the scraps reach the nip portion, they are heated by the heating roller and further pressed by the pressure roller, so that the scraps may be welded to the printing paper. For this reason, the fixing device is equipped with a cleaning roller for removing the shaving residue. The cleaning roller is pressed against, for example, a pressure roller, and captures the shaving residue transferred to the pressure roller by contacting the roller surface of the pressure roller.

  When the support frame that rotatably supports the cleaning roller is made of sheet metal, a bearing made of resin is provided between the bearing groove of the support frame and the rotation shaft of the cleaning roller in order to enable smooth rotation. A member is provided. The bearing member is slidably attached to the bearing groove in order to move the cleaning roller in a direction in which the cleaning roller comes into contact with and separates from the pressure roller.

JP-A-5-333738 JP-A-8-297425

  However, when the bearing member comes into contact with the corner portion of the edge of the bearing groove, the bearing member may be scraped to newly generate scraps. This shaving residue enters the bearing groove and causes abnormal noise when the cleaning roller rotates. Moreover, when the bearing member is scraped, the pressure contact force to the pressure roller may be reduced, and the cleaning performance of the pressure roller may be reduced. Further, when the shavings of the bearing member move to the pressure roller, there is a possibility that the bearing member may be welded to the printing paper through the heating roller.

  In addition, even when the support frame that supports the pressure roller in pressure contact with the heating roller is made of sheet metal, abnormal noise during rotation of the pressure roller, reduction in pressure contact force against the heating roller, printing paper Problems such as welding of shavings can occur.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a roller support mechanism, a roller unit, and a fixing device that can stably support a rotating roller.

  A roller support mechanism according to one aspect of the present invention is configured to support a rotation shaft of a second rotation roller provided in parallel to the first rotation roller, and includes a support frame, a covering member, and a bearing. A member, a blocking portion, and an urging member; The support frame has a support groove extending in a direction away from the first rotation roller, and the rotation shaft is inserted into the support groove. The support frame is made of sheet metal. The covering member is attached to the support groove so as to cover each of a pair of side edges facing each other in the support groove. The covering member is made of sheet metal. The bearing member has a bearing groove for rotatably supporting the rotating shaft, and moves in a direction in which the bearing member is in contact with and separated from the bottom of the support groove with the covering member interposed between the bearing member and the support groove. It is mounted in the support groove as possible. The closing portion is provided on the covering member. The closing portion closes the first opening on the first rotating roller side in the support groove in a state where the bearing member is mounted in the support groove. The bearing member is made of resin. The urging member urges the support member in a direction away from the bottom.

  The roller unit which concerns on the other situation of this invention is equipped with the 2nd rotation roller which has a rotating shaft parallel to the 1st rotation roller supported rotatably, and the said roller support mechanism.

  A fixing device according to another aspect of the present invention includes the roller unit, a third rotating roller, a first rotating roller, a separation member, and a cleaning member. The third rotating roller is heated by a heating device and is configured to be rotatable. The first rotating roller is configured to be rotatable while being pressed against the third rotating roller. The separation member abuts on the surface of the third rotation roller and separates the sheet passing through the nip portion between the third rotation roller and the first rotation roller from the third rotation roller. The separation member is made of resin. The cleaning member is provided on a surface of the second rotating roller of the roller unit. The cleaning member contacts the first rotating roller and adheres to the surface of the first rotating roller to remove foreign matter.

  According to the present invention, it is possible to stably support a rotating roller provided in a fixing device or the like.

FIG. 1 is a diagram illustrating a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a configuration of the fixing device according to the embodiment of the present invention. FIG. 3 is a diagram showing the configuration of the roller unit according to the embodiment of the present invention. 4A is a view of the right end portion of the roller unit of FIG. 3 as viewed from the front side, and FIG. 4B is a view of the right end portion of the roller unit of FIG. 3 as viewed from the right side. FIG. 5 is a diagram illustrating a configuration of the roller support mechanism according to the embodiment of the present invention. FIG. 6 is a diagram illustrating a configuration of a covering member of the roller support mechanism of FIG. FIG. 7 is a diagram illustrating a configuration of a connection mechanism of a covering member of the roller support mechanism of FIG. FIG. 8 is a diagram illustrating a configuration of a covering member of the roller support mechanism of FIG. FIG. 9 is an exploded view of the roller support mechanism of FIG. 10A and 10B are diagrams showing another example of the covering member of the roller support mechanism of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. In addition, embodiment described below is only an example which actualized this invention, and does not limit the technical scope of this invention.

[Image forming apparatus 10]
FIG. 1 is a diagram illustrating a configuration of an image forming apparatus 10 according to an embodiment of the present invention. For convenience of explanation, the vertical direction is defined as the vertical direction 8 in the installation state (the state shown in FIG. 1) in which the image forming apparatus 10 can be used. Further, the front-rear direction 7 is defined with the front surface (front surface) as the front surface (front surface) in which the paper feed cassette 40 shown in FIG. Further, a left-right direction 9 is defined with reference to the front surface of the installed image forming apparatus 10.

  The image forming apparatus 10 includes a housing 10A. The housing 10A has a substantially rectangular parallelepiped shape as a whole. Each part constituting the image forming apparatus 10 is disposed inside the housing 10A. As shown in FIG. 1, an opening 56 that is wide in the left-right direction 9 is formed in the lower portion of the front surface of the housing 10 </ b> A, and the paper feed cassette 40 can be accommodated inside the housing 10 </ b> A from the opening 56. It is.

  The image forming apparatus 10 is a so-called tandem color image forming apparatus, and includes a plurality of image forming units 4, an intermediate transfer belt 5, an optical scanning device 13, a secondary transfer roller 20, a fixing device 16, a sheet tray 18, and a paper feed. A cassette 40, a paper feed unit 32, an operation display unit 25, a transport path 26, and the control unit 2 are provided. The image forming apparatus 10 forms a monochrome image or a color image on the sheet S based on the input image data. The sheet S is paper, coated paper, a postcard, an envelope, an OHP sheet, or the like. Note that the image forming apparatus 10 according to the embodiment of the present invention is not limited to a tandem color image forming apparatus, but is a printer, a copier, a facsimile, or a multifunction machine having these functions. It may be.

  The operation display unit 25 is a touch panel that displays various types of information in accordance with control instructions from the control unit 2 and inputs various types of information to the control unit 2 in response to user operations.

  Each of the image forming units 4 (4C, 4M, 4Y, 4K) includes a photosensitive drum 11, a charging device 12, a developing device 14, a primary transfer roller 15, and the like, and forms an image according to an electrophotographic method. The image forming units 4 are arranged along the running direction (horizontal direction) of the intermediate transfer belt 5 and form a color image based on a so-called tandem method. Specifically, a toner image corresponding to C (cyan) in the image forming unit 4C, M (magenta) in the image forming unit 4M, Y (yellow) in the image forming unit 4Y, and K (black) in the image forming unit 4K is formed. Is done. The cyan image forming unit 4C, the magenta image forming unit 4M, the yellow image forming unit 4Y, and the black image forming unit 4K are arranged in this order from the downstream side in the moving direction (arrow 19 direction) of the intermediate transfer belt 5. They are arranged in a line in that order.

  The intermediate transfer belt 5 is a member to which toner images of respective colors formed on the photosensitive drums 11 of the image forming units 4 are intermediately transferred. The intermediate transfer belt 5 is supported by a driving roller 6A and a driven roller 6B so as to be rotationally driven. By being supported by the driving roller 6 </ b> A and the driven roller 6 </ b> B, the intermediate transfer belt 5 can move (run) while the surface thereof is in contact with the surface of each photosensitive drum 11. Then, when the surface of the intermediate transfer belt 5 passes between the photosensitive drum 11 and the primary transfer roller 15, the toner images are sequentially superimposed and transferred from the photosensitive drums 11. The optical scanning device 13 includes a laser light source that emits laser light of each color, a polygon mirror that scans the laser light, and mirrors 13C, 13M, 13Y, and 13K that emit the scanned laser light. The optical scanning device 13 forms an electrostatic latent image on each photoconductive drum 11 by irradiating the photoconductive drum 11 of each image forming unit 4 with laser light based on the input image data of each color.

  The paper feed unit 32 takes out the sheets S stacked in the paper feed cassette 40 one by one and feeds the sheets S toward the transport path 26.

  In the image forming apparatus 10 configured as described above, a color image is formed on the sheet S supplied from the paper feed cassette 40 along the conveyance path 26 by the following procedure, and the sheet S after the image formation is formed on the sheet tray 18. Discharged. The transport path 26 is provided with various transport rollers that transport the sheets S stacked on the paper feed cassette 40 to the sheet tray 18 via the secondary transfer roller 20 and the fixing device 16.

  First, in each image forming unit 4, the photosensitive drum 11 is uniformly charged to a predetermined potential by the charging device 12. Next, the optical scanning device 13 irradiates the surface of each photoconductive drum 11 with laser light based on the image data, thereby forming an electrostatic latent image on the surface of each photoconductive drum 11. The electrostatic latent images on the photosensitive drums 11 are developed (visualized) as toner images of respective colors by the developing devices 14. Each developing device 14 is supplied with toner (developer) from removable toner containers 3 (3C, 3M, 3Y, 3K) corresponding to the respective colors.

  Subsequently, the toner images of the respective colors formed on the photosensitive drums 11 of the image forming units 4 are sequentially superimposed and transferred onto the intermediate transfer belt 5 by the primary transfer rollers 15. As a result, a color image based on the image data is formed on the intermediate transfer belt 5. Next, the color image on the intermediate transfer belt 5 is transferred by the secondary transfer roller 20 to the sheet S conveyed from the paper feed cassette 40 via the conveyance path 26. The sheet S on which the color image is transferred is conveyed to the fixing device 16 by the conveyance roller.

  The fixing device 16 includes a heating roller 16A (an example of a third rotating roller) that is heated to a high temperature, and a pressure roller 16B (an example of a first rotating roller) that is disposed to face the heating roller 16A. The sheet S conveyed to the fixing device 16 is conveyed while being sandwiched between the heating roller 16A and the pressure roller 16B. As a result, the color image is welded to the sheet S. Thereafter, the sheet S is discharged to the sheet tray 18. Details of the configuration of the fixing device 16 will be described later.

  The control unit 2 performs overall control of the image forming apparatus 10. The control unit 2 is configured as a microcomputer whose main components are a CPU, ROM, RAM, EEPROM, and the like. The control unit 2 is connected to each image forming unit 4, the secondary transfer roller 20, the fixing device 16, the driving roller 6 </ b> A, the paper feeding unit 32, and the like inside the image forming apparatus 10, and controls these components. To do. The control unit 2 is connected to each element constituting the image forming unit 4, specifically, the charging device 12, the optical scanning device 13, the developing device 14, the primary transfer roller 15, and the like.

[Fixing device 16]
Hereinafter, the fixing device 16 according to the embodiment of the present invention will be described. As shown in FIG. 2, the fixing device 16 includes a heating roller 16A, a pressure roller 16B, a heater 51 (an example of a heating device), a separation blade 52 (an example of a separation member), and a cleaning unit 70 (a roller). An example of a unit). These components are provided inside the casing 53 of the fixing device 16.

  The heating roller 16A has a roller body 61 formed in a cylindrical shape. The roller surface of the roller body 61 is brought into contact with the developing surface of the sheet S (the surface on which the toner image is adhered) during fixing. The roller body 61 is made of a material having high thermal conductivity, and is made of a metal such as aluminum, for example. The surface of the roller body 61 is coated with a fluororesin layer for improving toner separation. A rotating shaft (not shown) is provided at both ends of the roller body 61, and the rotating shaft is rotatably supported by an internal frame or the like constituting the housing 53. Thereby, the heating roller 16A can be rotated.

  The heating roller 16 </ b> A has a heater 51. The heater 51 is provided inside the roller body 61. The heater 51 is composed of, for example, a halogen lamp. The heater 51 extends in the axial direction inside the roller body 61, and the roller body 61 is heated from the inside in the axial direction by the heater 51. The heater 51 is merely an example of a heating device, and instead of this, another heating device such as an induction heating device that generates heat from the heating roller 16A itself by the action of magnetic flux may be applied.

  The pressure roller 16B is disposed to face the heating roller 16A and is provided in parallel to the heating roller 16A. The pressure roller 16B is arranged behind the heating roller 16A in FIG. The pressure roller 16B is supported by the housing 53 so as to be rotatable in a state where it is pressed against the surface of the heating roller 16A with a predetermined pressure. Specifically, a rotation shaft 62 is provided at the center of the pressure roller 16 </ b> B, and the rotation shaft 62 is rotatably supported by an internal frame or the like constituting the housing 53. Thereby, the pressure roller 16B can be rotated. The pressure roller 16B is connected to a motor that is driven and controlled by the control unit 2 (see FIG. 1). When the motor is rotationally driven, the pressure roller 16B receives the rotational driving force and rotates in the clockwise direction in FIG. The rotating shaft 62 of the pressure roller 16B is provided with a cylindrical elastic portion 63 such as elastic silicon or porous rubber. Further, the pressure roller 16B is pressed against the heating roller 16A by a spring or the like. As a result, the elastic portion 63 is pressed against the roller body 61, whereby the nip portion 64 is formed between the heating roller 16A and the pressure roller 16B, and the elastic portion 63 is elastically deformed and recessed in a curved shape. The Further, the heating roller 16A is rotated in the counterclockwise rotation direction in FIG. 2 following the rotation of the pressure roller 16B by the contact friction at the nip portion 64.

  In the fixing device 16, the sheet S is conveyed so as to pass through the nip portion 64 from the bottom to the top. A separation blade 52 is provided downstream of the nip portion 64 in the paper conveyance direction. The separation blade 52 is a separation member for preventing the sheet S that has passed through the nip portion 64 from sticking to the heating roller 16 </ b> A and winding it. A plurality of separation blades 52 are arranged along the longitudinal direction of the heating roller 16A. In the present embodiment, the separation blade 52 is formed in a shape with a sharp tip, and the tip is in contact with the roller surface of the heating roller 16A. Thereby, the separation blade 52 can separate the sheet S from the heating roller 16A at the timing when the sheet S comes out of the nip portion 64. The separation blade 52 is made of a synthetic resin in order to prevent damage to the roller surface of the heating roller 16A.

  When the separation blade 52 is made of a synthetic resin, the separation blade 52 may be worn due to contact friction with the rotating heating roller 16 </ b> A, and shavings may be generated. When the scrap is transferred to the heating roller 16A and reaches the nip portion 64 by the rotation of the heating roller 16A, the scrap is heated by the heating roller 16A and further pressed by the pressure roller 16B, whereby the sheet S is scraped. Waste may be welded. For this reason, in this embodiment, the cleaning unit 70 is provided in the fixing device 16.

[Cleaning unit 70]
Hereinafter, the cleaning unit 70 will be described. As shown in FIG. 2, the cleaning unit 70 is provided below the pressure roller 16B. As shown in FIG. 3, the cleaning unit 70 is formed in a shape that is long in the longitudinal direction of the pressure roller 16B, and extends in a direction perpendicular to the paper surface in FIG. Yes. This cleaning unit 70 is for cleaning the roller surface of the pressure roller 16B by capturing the scraps transferred from the heating roller 16A to the pressure roller 16B. 2 and 3, the cleaning unit 70 includes a cleaning roller 71 (an example of a second rotating roller) and a support mechanism 80 (an example of a roller support mechanism) for supporting the cleaning roller 71. Prepare. The support mechanism 80 includes a support frame 81, a covering member 82, a bearing member 83, and a biasing member 84. In FIG. 2, the bearing member 83 and the urging member 84 are not shown. In FIG. 3, a part of the configuration of the left end portion of the support frame 81 is not shown.

  The cleaning roller 71 is provided in parallel to the pressure roller 16B. The cleaning roller 71 is supported by the support mechanism 80 so as to be rotatable while being pressed against the surface of the pressure roller 16B with a predetermined pressure. A rotation shaft 72 is provided at the center of the cleaning roller 71, and the rotation shaft 72 is rotatably supported by the support mechanism 80. A cleaning member 73 made of a nonwoven fabric or the like is provided on the rotating shaft 72 of the cleaning roller 71. The cleaning member 73 constitutes a roller surface of the cleaning roller 71. The cleaning member 73 removes foreign matters such as the shavings adhering to the surface of the pressure roller 16B when the cleaning roller 71 is pressed against the surface of the pressure roller 16B. Further, when the pressure roller 16B rotates, the cleaning roller 71 rotates in the counterclockwise rotation direction in FIG. 2 following the rotation of the pressure roller 16B due to contact friction with the pressure roller 16B. The cleaning member 73 is not limited to a non-woven fabric, and any material can be used as long as it can remove foreign matters such as the scraps.

  As shown in FIGS. 3 and 4, the support frame 81 is formed in a shape that is long in the left-right direction 9. The support frame 81 is made of a so-called sheet metal. In the present embodiment, the support frame 81 is made of a steel plate such as SPCC. The support frame 81 is formed by cutting or bending a sheet metal. As shown in FIG. 4, the support frame 81 has a base portion 81A. The base portion 81 </ b> A has a shape that is long in the left-right direction 9. The base portion 81 </ b> A constitutes the bottom portion of the cleaning unit 70, and the base portion 81 </ b> A is fixed to the housing 53 of the fixing device 16. At both ends in the longitudinal direction of the base portion 81A, side portions 81B are formed in which both ends of the base portion 81A are vertically bent upward.

  A support groove 85 extending in a direction away from the pressure roller 16B, that is, downward is formed in the side portion 81B. That is, the support frame 81 has a support groove 85. As will be described later, in this embodiment, the rotating shaft 72 of the cleaning roller 71 is inserted into the support groove 85 with the covering member 82 interposed between the support groove 85 and the support groove 85.

  A front portion 81C (an example of a charge removal portion) in which the front end of the base portion 81A is vertically bent upward is formed at the front end portion of the base portion 81A. That is, the support frame 81 has a front portion 81C. The front portion 81C extends to a position close to the roller surface of the pressure roller 16B. The front portion 81C plays a role of removing static electricity charged in the pressure roller 16B in the vicinity of the pressure roller 16B. An inclined portion 89 that is inclined forward is provided at the upper end portion of the front portion 81C. In the inclined portion 89, the facing surface 87 on the pressure roller 16B side faces the outer peripheral surface of the pressure roller 16B. A buffer material 88 such as felt having a shape that is long in the longitudinal direction of the support frame 81 is attached to the facing surface 87. In FIG. 3, the cushioning material 88 is not shown. As a result, even if the pressure roller 16B or the support mechanism 80 is displaced due to an impact from the outside or the environmental temperature, the inclined portion 89 does not directly contact the pressure roller 16B, and the cushioning material 88. This prevents the pressure roller 16B from being damaged. In addition, as long as the buffer material 88 produces a buffer function, the thing of materials other than felt is applicable.

  As shown in FIG. 5B, a protrusion 86 is provided on the bottom 85 </ b> A of the support groove 85. That is, the support frame 81 has the protrusion 86. The protrusion 86 protrudes upward from the center of the bottom 85A. The protrusion 86 is for supporting the lower end of the biasing member 84 and positioning the lower end at the center of the bottom 85A. The urging member 84 is a coil spring. As shown in FIG. 5A, the protrusion 86 is inserted into the urging member 84 at the lower end of the urging member 84, so that the lower end of the urging member 84 is supported by the support groove 85.

  The covering member 82 is attached to the support groove 85. Specifically, the covering member 82 is attached to the support groove 85 so as to cover each of the pair of side edge portions 85B (see FIG. 5B) facing each other in the support groove 85. The covering member 82 is made of a so-called sheet metal. In the present embodiment, the support frame 81 is made of a steel plate such as SUS (stainless steel). The covering member 82 is formed by cutting or bending a sheet metal.

  As shown in FIG. 6, the covering member 82 has a pair of first portions 82 </ b> A that cover the pair of side edge portions 85 </ b> B, and a second portion 82 </ b> B that covers the bottom portion 85 </ b> A of the support groove 85. As shown in FIG. 5A, the first portion 82A is not limited to the end of the side edge 85B on the support groove 85 side, but also the range from the end to the side of the side 81B (FIG. 5B ) In (). Thereby, the coating | coated member 82 can cover the corner | angular part 85B1 of the edge part of the side edge part 85B. In the present embodiment, the first portion 82A is formed by bending a sheet metal so as to cover the side edge portion 85B. For this reason, the end portion 94A in the width direction of the inner side surface 94 of the first portion 82A is not sharp but is a rounded curved surface.

  Of the pair of first parts 82A, the first part 82A1 on the rear side is provided with a closing plate 100 (an example of a blocking part). That is, the covering member 82 has the closing plate 100. The closing plate 100 is formed integrally with the covering member 82. Therefore, the closing plate 100 is made of sheet metal like the covering member 82. The closing plate 100 is a member for closing the support groove 85 of the support frame 81 and is formed in a narrow plate shape. The closing plate 100 is a member that closes the opening 85C (see FIG. 5B, an example of the first opening) on the cleaning groove 71 side in the support groove 85 in a state where the bearing member 83 is mounted in the support groove 85. It is.

  The closing plate 100 is provided at the upper end portion 101 (the end portion on the pressure roller 16B side) of the first portion 82A1. The closing plate 100 is a plate-like long member extending from the upper end portion 101 toward the other first portion 82A2 located on the front side, and the extending end 102 reaches the first portion 82A2. Yes. As shown in FIG. 6, the extending end 102 of the closing plate 100 is connected to the first portion 82A2 by a connecting mechanism 105 described later. Since the closing plate 100 is provided, the bearing member 83 is attached to the support groove 85 together with the covering member 82 as described later, and the rotating shaft 72 of the cleaning roller 71 is supported by the bearing member 83. The closing plate 100 functions as a stopper, and the bearing member 83 is prevented from coming out upward and the rotating shaft 72 is prevented from coming out upward. In addition, the obstruction | occlusion plate 100 should just be provided in at least one of a pair of 1st site | parts 82A. Moreover, the closing plate 100 may be provided in both of the pair of first portions 82A, and the extending ends may be connected to each other.

  The closing plate 100 can be formed in a straight shape extending upward from the upper end portion 101 so as to be continuous with the inner side surface 94, and the opening portion 85 </ b> C can be closed by bending the upper end portion 101. It is. As shown in FIG. 7, the connecting mechanism 105 includes an engaged portion 106 provided at the upper end portion of the first portion 82A2 and a pair of engaging portions 107 provided at the extended end 102. Yes. The engaged portion 106 and the engaging portion 107 are configured to be connectable to each other and configured to be able to release the connection. The engaged portion 106 is formed in a bowl shape. Specifically, the engaged portion 106 is a plate-like member protruding upward from the upper end portion of the first portion 82A2, and has rectangular cutout grooves 106A on both side surfaces in the width direction. Further, the engaging portion 107 is a protrusion that protrudes from both ends of the extending end 102 in the width direction. By inserting the engaging portion 107 into the notch groove 106A of the engaged portion 106, the extending end 102 of the closing plate 100 is connected to the first portion 82A2. As described above, since the closing plate 100 is bent and deformed at the upper end portion 101, a restoring force (elastic force) is generated in a direction (upward in FIG. 6) in which the closing plate 100 tries to return to the original state after the bending deformation. On the other hand, the engaged portion 106 of the coupling mechanism 105 is engaged so as not to move the engaging portion 107 upward. Therefore, even when the restoring force is generated, the connection state by the connection mechanism 105 is maintained. In addition, the connection by the connecting mechanism 105 is released by removing the engaging portion 107 from the notch groove 106A of the engaged portion 106.

  As illustrated in FIG. 6, the second portion 82 </ b> B of the covering member 82 is provided with an opening 90 (an example of a second opening). The opening 90 is an opening formed in the facing surface 91 disposed to face the bottom 85A in the second portion 82B. The opening 90 is formed in a size that allows the projection 86 of the bottom 85A to be inserted when the covering member 82 is attached to the support groove 85. That is, when the covering member 82 is attached to the support groove 85, the protrusion 86 protrudes upward through the opening 90 and is exposed to the support groove 85. In this state, the urging member 84 is attached to the protrusion 86.

  In addition, the covering member 82 is formed so that each of the pair of first portions 82A generates an elastic force that presses the corresponding side edge portion 85B outward while being attached to the support groove 85. Specifically, as shown in FIG. 8, each of the pair of first portions 82A is inclined in a direction away from each other. That is, the first part 82A1 on the rear side is inclined outward (rear side) by an angle θ with respect to the vertical direction with the joint point with the second part 82B as a fulcrum. Further, the first portion 82A2 on the front side is inclined outward (front side) by an angle θ with respect to the vertical direction with a joint point with the second portion 82B as a fulcrum. The inclination angle θ is set so that the separation distance of the first portion 82A is larger than at least the width of the support groove 85 in the front-rear direction 7. For this reason, the covering member 82 is stably supported in the supporting groove 85 by mounting the covering member 82 in the supporting groove 85 narrower than the covering member 82. Although not shown, a mechanism may be provided that engages the covering member 82 and the inner wall of the supporting groove 85 when the covering member 82 is mounted in the supporting groove 85.

  The bearing member 83 is attached to the support groove 85 together with the covering member 82. The bearing member 83 is made of a synthetic resin. In this embodiment, the bearing member 83 is manufactured by molding a polyphenylene sulfide resin (PPS resin) that has high heat resistance, high strength and rigidity, and excellent wear resistance. . Of course, the bearing member 83 may be made of a synthetic resin other than the PPS resin. The bearing member 83 has a bearing groove 83A (see FIG. 5B). The bearing groove 83 </ b> A is a part that supports the rotating shaft 72 of the cleaning roller 71, and is formed in the upper part of the bearing member 83. The bottom portion of the bearing groove 83A is formed in an arc shape that is substantially the same size as the rotation shaft 72, so that the bearing groove 83A can support the rotation shaft 72 so that it can rotate smoothly.

  The bearing member 83 is attached to the support groove 85 with the covering member 82 interposed between the bearing member 83 and the urging member 84 supported by the support groove 85 from above the covering member 82. The By mounting the bearing member 83 in the support groove 85, the bearing member 83 can move in a direction (vertical direction 8) that is in contact with or separated from the bottom 85 </ b> A of the support groove 85. In other words, the bearing member 83 is provided in the support groove 85 so as to be movable in the vertical direction 8. In order to allow the bearing member 83 to move in the support groove 85, the bearing member 83 is formed with a guide groove 83B (see FIG. 5B). As shown in FIG. 5B, the guide groove 83 </ b> B is formed on each end of the bearing member 83 in the front-rear direction 7. Each guide groove 83 </ b> B extends in the vertical direction 8. The groove width of the guide groove 83B is formed such that the first portion 82A of the covering member 82 can be inserted. The covering member 82 is attached to the support groove 85, and the first portion 82A of the covering member 82 is inserted into the guide groove 83B, so that the guide groove 83B guides the bearing member 83 so that it can move in the vertical direction 8. To do.

  The biasing member 84 is a coil spring. The biasing member 84 biases the bearing member 83 in a direction (upward) away from the bottom 85A. In the present embodiment, the urging member 84 is provided between the protrusion 86 protruding from the opening 90 of the covering member 82 and the bearing member 83 in a state where the covering member 82 is attached to the support groove 85. As shown in FIGS. 5A and 5B, a projecting spring seat 92 that is inserted from the upper end of the biasing member 84 into the biasing member 84 is provided at the bottom of the bearing member 83. Yes. The upper end of the urging member 84 is positioned by the spring seat 92, and the lower end is positioned by the protrusion 86, whereby the urging member 84 is disposed between the bottom portion 85A and the bearing member 83. The urging member 84 is not limited to a coil spring. As long as the bearing member 83 is urged upward in a state where it is attached to the support groove 85, it is not limited to a spring-biased one, but can be applied to an elastic member such as rubber or any other configuration. It is.

  The bearing member 83 is attached to the support groove 85 by the following attachment procedure. That is, as shown in FIG. 9, first, only the lower end of the covering member 82 is inserted into the support groove 85. In this state, the closing plate 100 is not bent at the upper end 101, and maintains a straight posture along the first portion 82A1, as indicated by a broken line in FIG. Further, since the first portion 82A of the covering member 82 is inclined outward by the angle θ, the distance between the first portions 82A is larger than the width of the support groove 85. In this state, the bearing member 83 is inserted into the support groove 85 from above the urging member 84 while the urging member 84 is brought into contact with the opposing surface 91. Then, the covering member 82, the urging member 84, and the bearing member 83 are pushed downward as a unit, so that they enter the bottom portion 85 </ b> A of the support groove 85. In this entering process, the space between the first portions 82A is pushed by the side edge portion 85B and gradually narrowed. Then, in a state where the covering member 82, the biasing member 84, and the bearing member 83 are mounted in the support groove 85 (see FIG. 4B), the closing plate 100 covers the opening 85C with the upper end 101 as a fulcrum. Is bent to. Thereafter, the engaging portion 107 and the engaged portion 106 are engaged by the connecting mechanism 105, and the extending end 102 is connected to the first portion 82A2. Thereby, the closing plate 100 functions as a stopper, and the bearing member 83 and the rotating shaft 72 are prevented from coming out upward.

  Thus, since the support mechanism 80 of the cleaning unit 70 is configured, the bearing member 83 can move in the support groove 85 in the vertical direction 8, but directly on the corner 85 B 1 of the side edge 85 B of the support groove 85. Do not touch. Therefore, generation of scraps due to contact with the corner 85B1 is prevented. When the bearing member 83 moves, the bearing member 83 slides on the first portion 82A of the covering member 82, but the end portion 94A in the width direction of the inner side surface 94 of the first portion 82A is not sharp but has a rounded curved surface. It has become. Therefore, the bearing member 83 slides smoothly without being scraped off. By preventing the generation of the scraps, the scraps do not enter the bearing groove 83A of the bearing member 83, and an abnormal noise is generated during rotation between the rotating shaft 72 of the cleaning roller 71 and the bearing groove 83A. There is nothing. Further, since the scrap is not generated, the scrap is not welded to the sheet S and the image quality is not deteriorated.

  Further, as described above, since the covering member 82 is provided with the closing plate 100, even if the bearing member 83 moves upward from the support groove 85, the movement is stopped by the closing plate 100. Similarly, even if the rotating shaft 72 moves upward from the support groove 85, the movement is stopped by the closing plate 100. Thereby, the bearing member 83 and the rotating shaft 72 are prevented from coming out upward. That is, with the support mechanism 80 of the present embodiment, the cleaning roller 71 provided in the fixing device 16 can be stably supported.

  In the above-described embodiment, the first portion 82A of the covering member 82 covers a range (see FIG. 5B) that extends from the end of the side edge portion 85B on the support groove 85 side to the side surface of the side portion 81B. However, the present invention is not limited to this. If the covering member 82 can cover at least the corner portion 85B1 at the end of the side edge portion 85B, the shaving of the bearing member 83 by the corner portion 85B1 is prevented.

  In the above-described embodiment, the covering member 82 having the coupling mechanism 105 is illustrated, but the present invention is not limited to this covering member 82. For example, instead of the covering member 82, the covering member 111 shown in FIG. 10A can be applied to the support mechanism 80. The covering member 111 is not provided with the connecting mechanism 105. In the covering member 111, the closing plate 100 is integrally provided so as to bridge the upper ends of the first portions 82A. Further, the covering member 111 is not connected between the second part 82B and the first part 82A1, and the blocking plate 100, the first part 82A2, and the second part 82B are continuously integrated from the first part 82A1. It is configured. As shown in FIG. 10A, the covering member 111 is mounted in the support groove 85 in a state where the connecting portions of the respective portions are bent. Further, instead of the covering member 82, the covering member 112 shown in FIG. 10B can be applied to the support mechanism 80. This covering member 112 is also not provided with the connecting mechanism 105. In the covering member 112, the closing plate 100 is integrally provided so as to bridge the upper ends of the first portions 82A. Further, the second portion 82B is divided into left and right at the center position. In the covering member 112, the first portion 82A1, the blocking plate 100, the first portion 82A2, and the other second portion 82B2 are continuously and integrally formed from one divided second portion 82B1. As shown in FIG. 10B, the covering member 112 is attached to the support groove 85 in a state where the connecting portions of the respective portions are bent. Even with the covering members 111 and 112 configured as described above, the bearing member 83 and the rotating shaft 72 can be prevented from coming out upward, and the cleaning roller 71 provided in the fixing device 16 is stabilized. Can be supported.

  In the above-described embodiment, the support mechanism 80 for the cleaning roller 71 in the cleaning unit 70 has been illustrated, but the present invention is not limited to this. For example, the support mechanism 80 can also be applied to a mechanism that supports the pressure roller 16B in a pressure contact state with respect to the heating roller 16A.

10: Image forming device 16: Fixing device 16A: Heating roller 16B: Pressure roller 70: Cleaning unit 71: Cleaning roller 72: Rotating shaft 81: Support frame 82: Cover member 83: Bearing member 84: Energizing member 100: Blocking Plates 111 and 112: Cover members

Claims (11)

A roller support mechanism for supporting a rotation shaft of a second rotation roller provided in parallel to the first rotation roller,
A support frame that has a support groove extending in a direction away from the first rotation roller, and the rotation shaft is made of a sheet metal inserted into the support groove;
A covering member made of a sheet metal attached to the support groove so as to cover each of the pair of side edges facing each other in the support groove;
A bearing groove for rotatably supporting the rotating shaft, and the movable member is movable in a direction of contacting and separating from the bottom of the supporting groove with the covering member interposed between the rotating groove and the supporting groove; A bearing member made of resin to be mounted in the support groove;
A closing portion that is provided on the covering member and closes the first opening on the first rotating roller side in the support groove in a state where the bearing member is mounted in the support groove;
And a biasing member that biases the bearing member in a direction away from the bottom.   The roller support mechanism according to claim 1, wherein the closing portion is configured integrally with the covering member. The covering member has a pair of first portions covering each of the pair of side edges,
The blocking portion extends from an end on the first rotating roller side in one of the first portions to the other first portion, and the extending end is connected to the other first portion. Item 3. A roller support mechanism according to Item 2. The covering member has an engaged portion provided in the other first portion,
The closing portion is configured to be bent and deformable at the end portion in the first portion, and an engaging portion that engages with the engaged portion so as to be disengageable is provided at the extended end of the closing portion. The roller support mechanism according to claim 3.   The roller support mechanism according to claim 1, wherein the covering member covers at least a corner portion of the side edge portion.   4. The roller support mechanism according to claim 3, wherein the bearing member has a guide groove for inserting the first portion and guiding the bearing member in a direction in which the bearing member comes in contact with and separates from the bottom portion. The support frame has a protrusion provided at the bottom of the support groove,
The covering member has a second portion that covers the bottom portion, and a second opening that is formed in the second portion and through which the protrusion can be inserted,
The urging member is provided between the projection and the bearing member that protrude from the second opening in a state where the covering member is attached to the support groove. The roller support mechanism described.   The roller support mechanism according to any one of claims 1 to 7, wherein the support frame includes a static elimination unit that neutralizes static electricity charged in the second rotary roller in the vicinity of the second rotary roller.   The roller support mechanism according to claim 1, wherein the covering member generates an elastic force that presses the pair of side edge portions in a state of being attached to the support groove. A second rotating roller having a rotation axis parallel to the first rotating roller rotatably supported;
A roller unit comprising: the roller support mechanism according to claim 1. A roller unit according to claim 10;
A rotatable third rotating roller heated by a heating device;
A first rotating roller rotatable in a state of being pressed against the third rotating roller;
A separation member made of a resin that separates a sheet that contacts the surface of the third rotating roller and passes through a nip portion between the third rotating roller and the first rotating roller from the third rotating roller;
A fixing device provided on a surface of the second rotating roller of the roller unit, and a cleaning member that contacts the first rotating roller and adheres to the surface of the first rotating roller to remove foreign matters.

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