JP5838243B2 - Sheet peeling mechanism, fixing device, and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet peeling mechanism that peels a sheet from a rotating member, a fixing device including the sheet peeling mechanism, and an image forming apparatus including the sheet peeling mechanism and the fixing device.

  Conventionally, an electrophotographic image forming apparatus such as a copying machine or a printer is provided with a fixing device for fixing a toner image onto a sheet.

  The fixing device includes, for example, a fixing roller, a pressure roller that is in pressure contact with the fixing roller, and a fixing device body that rotatably supports the fixing roller and the pressure roller. The sheet is heated and pressed in a fixing nip formed between the fixing roller and the pressure roller to fix the toner image on the sheet.

  Further, in the fixing device having such a configuration, a peeling member is provided so as to come into contact with the fixing roller, and the paper on which the toner image is fixed is peeled from the fixing roller using the peeling member. ing. This peeling member is normally in contact with the fixing roller at all times. For this reason, the contact portion of the fixing roller with the peeling member is locally abraded, and there is a problem that an image defect occurs due to the toner entering the worn portion.

  Therefore, Patent Document 1 discloses a fixing device including a slide mechanism (see “thrust driving mechanism 150”) that reciprocates the peeling member in the rotation axis direction of the fixing roller. In this prior art, the contact position between the peeling member and the fixing roller is changed by sliding the peeling member with a slide mechanism, and local wear of the fixing roller is prevented.

JP 2002-357975 A

  However, in the prior art described in Patent Document 1, the slide mechanism is not attachable to and detachable from the fixing device body, and when the slide mechanism fails, the slide mechanism cannot be removed from the fixing device body and repaired. The nature was bad.

  Depending on the model of the image forming apparatus, the durability of the fixing roller may be sufficiently maintained without sliding the peeling member. However, in Patent Document 1, since the slide mechanism is not attachable to and detachable from the fixing device main body, the sheet is peeled off from the fixing roller with the slide mechanism always mounted on the fixing device main body even when sliding of the peeling member is unnecessary. The mechanism had to be used, and the paper peeling mechanism was unnecessarily complicated and increased in size.

  In view of the above circumstances, an object of the present invention is to improve the maintainability of the slide mechanism, and to simplify the configuration of the sheet peeling mechanism and save space when sliding of the peeling member is unnecessary. .

  The sheet peeling mechanism of the present invention includes a main body that rotatably supports a rotating member, a peeling member that comes into contact with the rotating member and peels the sheet from the rotating member, and the peeling member extends along the longitudinal direction of the rotating member. And a slide mechanism that slides on the main body, and a support member that supports the peeling member is slidably supported along the longitudinal direction of the rotating member, and the slide mechanism is detachably attached to the main body. A holder to be attached and a cam that is rotatably supported by the holder and that presses the support member along the longitudinal direction of the rotating member in accordance with the rotation, and is detachably provided to the main body. The cam is provided above the rotating member, and the rotating shaft of the cam is perpendicular to the longitudinal direction of the rotating member.

  By adopting such a configuration, when the slide mechanism breaks down, the slide mechanism can be removed from the main body and repaired, and the maintainability can be improved. If the durability of the rotating member can be sufficiently maintained without sliding the peeling member, the paper peeling mechanism can be used with the slide mechanism removed from the main body. It is possible to simplify the configuration and save space. In addition, the slide mechanism can be realized with a simple configuration using a cam.

  The sheet peeling mechanism of the present invention may further include a support plate fixed to the support member and provided with a pair of guide plates protruding, and the release member may be disposed between the pair of guide plates.

  In the sheet peeling mechanism of the present invention, the holder is provided with a cylindrical boss projecting, the cam is provided with a cylindrical boss receiving portion, and the boss receiving portion is engaged with the boss. By fastening the mounting member to the boss, the cam may be detachably mounted on the holder, and the cam may be rotatably supported by the holder.

  By adopting such a configuration, it is possible to easily replace the cam mounted on the holder with another cam with a different shape and outer diameter, and this change changes the slide speed and slide width of the peeling member. It becomes possible to do. That is, it is possible to manufacture a paper peeling mechanism with various specifications only by exchanging one cam.

  In the sheet peeling mechanism of the present invention, the main body is provided with a main body side engaging portion and a main body side fastening portion, and the holder has a holder side engaging portion that can be engaged with the main body side engaging portion at one end. The holder side fastening part that is provided in the part and can be fastened with the main body side fastening part may be provided at the end part opposite to the one end part.

  By adopting such a configuration, the holder can be firmly fixed to the main body with a simple configuration.

  The fixing device according to the present invention is a fixing device including any one of the above-described sheet peeling mechanisms, wherein the rotating member is a fixing roller that fixes a toner image on a sheet.

  The image forming apparatus of the present invention includes any one of the above-described sheet peeling mechanisms or fixing devices.

  According to the present invention, it is possible to improve the maintainability of the slide mechanism, and to simplify the configuration of the sheet peeling mechanism when it is unnecessary to slide the peeling member, thereby saving space.

1 is a schematic diagram illustrating an outline of a printer according to a first embodiment of the present invention. 1 is a perspective view showing a fixing device of a printer according to a first embodiment of the present invention. FIG. 2 is a plan view showing the vicinity of a communication opening of the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. FIG. 3 is a perspective view from the right rear side showing a state where the slide mechanism is removed from the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. FIG. 2 is a side view showing the inside of the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. FIG. 2 is a perspective view from the back side showing the inside of the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. In the fixing device of the printer according to the first embodiment of the present invention, it is a perspective view from the front side showing a support member and a peeling claw. FIG. 3 is a perspective view from the right front side showing the slide mechanism in the fixing device of the printer according to the first embodiment of the present invention. FIG. 3 is a perspective view from the right rear side showing a state where the slide mechanism is mounted on the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. In the fixing device of the printer according to the first embodiment of the present invention, (a) is a bottom view showing a state in which a portion closest to the rotation center a in the pressing portion of the cam is in contact with the support member. (B) is a bottom view which shows the state which the part furthest from the rotation center a is contacting the support member among the press parts of a cam. FIG. 9 is a perspective view from the right front side showing a slide mechanism in a fixing device of a printer according to a second embodiment of the present invention. In the fixing device of the printer according to the second embodiment of the present invention, (a) is a side view showing a state in which the first attachment portion is attached to the holder support portion, and (b) is the second attachment portion. It is a side view which shows the state attached to the holder support part. In the fixing device of the printer according to the second embodiment of the present invention, (a) is a perspective view showing a state where the first pressing portion of the cam is in contact with the support member, and (b) is a view of the cam. It is a perspective view which shows the state which the 2nd press part is contacting the support member.

<First Embodiment>
First, the overall configuration of the electrophotographic printer 1 will be described with reference to FIG. FIG. 1 is a schematic diagram illustrating an outline of a printer according to a first embodiment of the present invention. Hereinafter, the left side in FIG. 1 is the front side (front side) of the printer 1.

  The printer 1 includes a box-shaped printer main body 2. A paper feed cassette 3 for storing paper (not shown) is accommodated in the lower portion of the printer main body 2, and a paper discharge tray is disposed on the upper surface of the printer main body 2. 4 is provided. An upper cover 5 is attached to the upper surface of the printer main body 2 so as to be openable and closable in front of the paper discharge tray 4, and a toner container 6 is stored below the upper cover 5.

  An exposure unit 7 composed of a laser scanning unit (LSU) is disposed below the discharge tray 4 above the printer body 2, and an image forming unit 8 is provided below the exposure unit 7. Yes. The image forming unit 8 is rotatably provided with a photosensitive drum 10 as an image carrier. Around the photosensitive drum 10, a charger 11, a developing device 12, a transfer roller 13, and a cleaning device are provided. The apparatus 14 is disposed along the rotation direction of the photosensitive drum 10 (see arrow X in FIG. 1).

  A paper transport path 15 is provided inside the printer main body 2. A paper feed unit 16 is provided at the upstream end of the conveyance path 15, and a transfer unit 17 configured by the photosensitive drum 10 and the transfer roller 13 is provided at a middle portion of the conveyance path 15. Is provided with a fixing device 18, and a paper discharge unit 20 is provided at the downstream end of the conveyance path 15. A reverse path 21 for double-sided printing is formed below the transport path 15.

  Next, an image forming operation of the printer 1 having such a configuration will be described.

  When the printer 1 is turned on, various parameters are initialized, and initial setting such as temperature setting of the fixing device 18 is executed. Then, when image data is input from a computer or the like connected to the printer 1 and an instruction to start printing is given, an image forming operation is executed as follows.

  First, after the surface of the photosensitive drum 10 is charged by the charger 11, exposure corresponding to the image data is performed on the photosensitive drum 10 by laser light from the exposure device 7 (see the two-dot chain line P in FIG. 1). The electrostatic latent image is formed on the surface of the photosensitive drum 10. Next, the developing device 12 develops the electrostatic latent image into a toner image with toner.

  On the other hand, the sheet taken out from the sheet cassette 3 by the sheet feeding unit 16 is conveyed to the transfer unit 17 in synchronization with the above-described image forming operation, and the toner image on the photosensitive drum 10 is transferred to the sheet by the transfer unit 17. Is transcribed. The sheet on which the toner image has been transferred is conveyed downstream in the conveyance path 15 and enters the fixing device 18 where the toner image is fixed on the sheet. The paper on which the toner image is fixed is discharged from the paper discharge unit 20 to the paper discharge tray 4. The toner remaining on the photosensitive drum 10 is collected by the cleaning device 14.

  Next, details of the fixing device 18 will be described with reference to FIGS. FIG. 2 is a perspective view showing the fixing device of the printer according to the first embodiment of the present invention. FIG. 3 is a plan view showing the periphery of the communication opening of the fixing device body in the fixing device of the printer according to the first embodiment of the present invention. FIG. 4 is a perspective view from the right rear side showing a state in which the slide mechanism is removed from the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. FIG. 5 is a side view showing the inside of the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. FIG. 6 is a perspective view from the back side showing the inside of the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. FIG. 7 is a perspective view from the front side showing the support member and the peeling claw in the fixing device of the printer according to the first embodiment of the present invention. FIG. 8 is a perspective view from the right front side showing the slide mechanism in the fixing device of the printer according to the first embodiment of the present invention. FIG. 9 is a perspective view from the right rear side showing a state where the slide mechanism is mounted on the fixing device main body in the fixing device of the printer according to the first embodiment of the present invention. The left front side in FIG. 2 is the front side of the fixing device 18.

  As best shown in FIG. 2, the fixing device 18 includes a box-shaped fixing device main body 22. The fixing device main body 22 has a long shape in the left-right direction. On both the left and right sides of the upper surface of the fixing device main body 22, communication openings 23 that communicate with the internal space of the fixing device main body 22 are formed. Note that only the left side of the communication opening 23 is displayed in FIG.

  As shown in FIG. 3, each communication opening 23 has a rectangular shape in plan view. A support piece 24 is installed between the front surface and the rear surface of each communication opening 23 at the center in the left-right direction of each communication opening 23. Insertion holes 25 are formed in the support piece 24 in the left-right direction, so that the support piece 24 has a substantially cylindrical shape. The support piece 24 is not shown in FIG.

  As shown in FIG. 4, on the upper surface of the fixing device main body 22, a flat plate-like protruding piece 26 as a main body side engaging portion protrudes rearward from the right rear side of the right communication opening 23. On the upper surface of the fixing device main body 22, a pair of left and right protrusions 27 are provided in front of the right communication opening 23. On the upper surface of the fixing device main body 22, a holder support portion 28 is formed in front of the pair of left and right protrusions 27, and the holder support portion 28 has a screw hole 30 as a main body side fastening portion.

  As shown in FIG. 5, a fixing roller 31 as a rotating member is rotatably supported inside the fixing device main body 22. The fixing roller 31 includes, for example, a cylindrical member formed of a metal such as aluminum or iron having excellent thermal conductivity, and a coating layer (for example, a fluororesin layer) that covers the surface of the cylindrical member. Is done. In the internal space of the fixing roller 31, a heater 32 configured by, for example, a halogen heater or a ceramic heater is accommodated. The heater 32 generates heat when energized and heats the fixing roller 31.

  As shown in FIG. 6, the fixing roller 31 has a shape that is long in the left-right direction. At the right end of the fixing roller 31 (the left end in the drawing of FIG. 6), a fixing roller rotating gear 33 is provided so as to rotate together with the fixing roller 31. The fixing roller rotating gear 33 is connected to driving means (not shown) such as a motor, and the fixing roller 31 is rotated by transmitting the rotational driving force of the driving means to the fixing roller rotating gear 33. It is configured as follows. An idle gear 34 that meshes with the fixing roller rotating gear 33 is rotatably supported by the fixing device main body 22 above the fixing roller rotating gear 33.

  As shown in FIG. 5, a pressure roller 35 is rotatably supported inside the fixing device main body 22 below the fixing roller 31. The pressure roller 35 is formed of, for example, a cylindrical base material layer formed of synthetic resin, metal, etc., an elastic layer formed of silicon rubber or the like and provided around the base material layer, and a fluororesin And a coating layer covering the elastic layer. The pressure roller 35 is in pressure contact with the fixing roller 31 by an urging force of an urging means (not shown), and is configured such that the pressure roller 35 rotates following the rotation of the fixing roller 31. A fixing nip 36 is formed between the fixing roller 31 and the pressure roller 35, and the toner image is fixed on the sheet by heating and pressing the sheet conveyed along the conveying path 15 in the fixing nip 36. It is supposed to let you. The pressure roller 35 has a long shape in the left-right direction (see FIG. 6).

  As shown in FIGS. 5, 6, etc., a support member 37 is provided inside the fixing device main body 22 so as to face the peripheral surface of the fixing roller 31. As best shown in FIG. 7, the support member 37 includes a mounting plate 38 formed of sheet metal. The mounting plate 38 includes a fixing portion 40 extending in the left-right direction and a bent portion 41 bent upward from both left and right ends of the fixing portion 40, and has a U-shape when viewed from the front.

  A pair of left and right peeling claw support plates 42 are fixed to the lower surface of the fixing portion 40 of the mounting plate 38 by fastening means (not shown) such as screws. Each peeling claw support plate 42 is made of resin and has a long shape in the left-right direction. A pair of left and right guide plates 43 project downward from the left and right sides of each peeling claw support plate 42. A total of four sets of left and right guide plates 43 are provided, two for each peeling claw support plate 42.

  A peeling claw 44 as a peeling member is disposed between the pair of left and right guide plates 43. Four peeling claws 44 are arranged corresponding to the pair of left and right guide plates 43. Each peeling claw 44 is supported by each peeling claw support plate 42 so as to be swingable about the upper end side as a fulcrum. A sharp contact portion 45 is provided at the lower end of each peeling claw 44. As shown in FIG. 5, the contact portion 45 is urged toward the circumferential surface of the fixing roller 31 by a torsion coil spring 46 disposed in the vicinity of the swing fulcrum of the peeling claw 44, and is pressed against the circumferential surface of the fixing roller 31. doing. The sheet on which the toner image is fixed in the fixing nip 36 can be peeled off from the peripheral surface of the fixing roller 31 by the contact portion 45 of the peeling claw 44.

  As shown in FIG. 7, a columnar protrusion 47 protruding to the right is fixed to each bent portion 41 of the mounting plate 38. As shown in FIG. 3, the protrusion 47 is disposed in the communication opening 23 of the fixing device main body 22 and is inserted into the insertion hole 25 of the support piece 24. As a result, the support member 37 is supported by the fixing device main body 22 in a state in which it can slide along the longitudinal direction of the fixing roller 31 (the left-right direction in the present embodiment). A coil spring 48 as an urging member is interposed between the bent portion 41 at the right end of the mounting plate 38 and the left surface of the right communication opening 23, and the support member 37 is moved to the right by the coil spring 48. Is being energized.

  As shown in FIG. 2, a slide mechanism 50 is detachably attached to the right end of the upper surface of the fixing device main body 22. As best shown in FIG. 8, the slide mechanism 50 includes a holder 51 having a box shape with the front and upper sides opened. At the rear end of the right side plate 52 of the holder 51, a hook 53 as a holder side engaging portion is provided. The hook 53 includes a first flat plate portion 54 that extends in the vertical direction, and a second flat plate portion 55 that protrudes forward from the lower end of the first flat plate portion 54. It is made. A through hole 57 as a holder side fastening portion is formed in the front end portion of the bottom plate 56 of the holder 51 in the vertical direction. Then, as shown in FIG. 9, with the hook 53 of the holder 51 engaged with the protruding piece 26 of the fixing device main body 22, the screw inserted through the insertion hole 57 (see FIG. 8) of the holder 51. The slide mechanism 50 is detachably attached to the fixing device body 22 by fastening 58 to the screw hole 30 (see FIG. 4) of the fixing device body 22.

  As shown in FIG. 8, a round hole 59 is formed in the vertical direction on the right front portion of the bottom plate 56 of the holder 51, and a long hole 60 is formed in the vertical direction on the left side of the round hole 59. As shown in FIG. 2, the protrusion 27 on the right side of the fixing device main body 22 is engaged with the round hole 59, and the protrusion 27 on the left side of the fixing device main body 22 is engaged with the long hole 60.

  As shown in FIG. 8, a cylindrical boss 62 provided with a mounting screw hole 61 projects from the center of the bottom plate 56 of the holder 51. A rectangular insertion opening 63 is formed in the vertical direction on the left side of the boss 62, and the right bent portion 41 of the mounting plate 38 of the support member 37 is inserted into the insertion opening 63.

  A first connection gear 66 having a large diameter portion 64 and a small diameter portion 65 is rotatably supported on the outer side (right side) of the right side plate 52 of the holder 51. As shown in FIG. 9, the large diameter portion 64 of the first connection gear 66 meshes with the idle gear 34 of the fixing device main body 22.

  As shown in FIG. 8, a second connection gear 67 is provided outside the right side plate 52 of the holder 51 behind the first connection gear 66. The second connection gear 67 meshes with the small diameter portion 65 of the first connection gear 66. The rotation shaft 68 of the second connection gear 67 is rotatably supported by bearing holes 71 provided in the right side plate 52 and the left side plate 70 of the holder 51. A worm gear 72 is provided on the left side of the rotation shaft 68 of the second connection gear 67. The worm gear 72 is accommodated in the rear end portion in the holder 51.

  A cam 73 is accommodated in the center of the holder 51. A cylindrical boss receiving portion 74 is provided at the center of the cam 73. With the boss receiving portion 74 engaged with the boss 62 of the holder 51, a mounting screw is inserted into the mounting screw hole 61 of the boss 62 of the holder 51. By fastening 75 (attachment member), the cam 73 is detachably attached to the holder 51, and the cam 73 is rotatably supported by the holder 51. A drive gear 76 that meshes with the worm gear 72 is provided on the upper portion of the cam 73. As shown in FIG. 6, an elliptical pressing portion 77 is provided integrally with the drive gear 76 at the lower portion of the cam 73. The pressing portion 77 is in contact with the bent portion 41 on the right side (the left side in the drawing of FIG. 6) of the mounting plate 38 of the support member 37.

  As described above, in the present embodiment, the fixing device main body 22, the peeling claw 44, and the slide mechanism 50 are mainly used as a mechanism for peeling the paper from the fixing roller 31 (hereinafter referred to as “paper peeling mechanism”). ) Is formed.

  In the configuration as described above, when the printer 1 is in the standby state, the driving means (not shown) does not rotate the fixing roller rotating gear 33, and the fixing roller 31 and the pressure roller 35 are not rotated. The rotation has stopped.

  On the other hand, when image data is input from an external computer or the like and the printer 1 shifts from the standby state to the image forming state, the driving means (not shown) rotates the fixing roller rotating gear 33, and the fixing roller 31 and The pressure roller 35 rotates. The rotation of the fixing roller rotating gear 33 is transmitted to the drive gear 76 of the cam 73 through the idle gear 34, the first connection gear 66, the second connection gear 67, and the worm gear 72, and the cam 73 rotates.

  The action associated with the rotation of the cam 73 will be described with reference to FIG. FIG. 10A shows a fixing device for a printer according to the first embodiment of the present invention, in which FIG. 10A shows a state in which a portion of the cam pressing portion closest to the rotation center a is in contact with the support member. It is a bottom view, (b) is a bottom view which shows the state in which the part furthest from the rotation center a is contacting the support member among the press parts of a cam.

  In the pressing portion 77 of the cam 73, the cam is moved from the state where the portion closest to the rotation center a (distance L1 from the rotation center a) is in contact with the right bent portion 41 of the support member 37 (see FIG. 10A). When 73 rotates, the right bent portion 41 of the support member 37 is pressed to the left by the pressing portion 77 of the cam 73, and the support member 37 slides to the left against the urging force of the coil spring 48. As the support member 37 slides, the four peeling claws 44 supported by the support member 37 slide to the left while maintaining the contact state with the fixing roller 31.

  On the other hand, in the pressing portion 77 of the cam 73, the portion farthest from the rotation center a (distance L2 from the rotation center a) is in contact with the bent portion 41 on the right side of the support member 37 (see FIG. 10B). ), The support member 37 slides to the right by the urging force of the coil spring 48. As the support member 37 slides, the four peeling claws 44 supported by the support member 37 slide to the right while maintaining the contact state with the fixing roller 31.

  As long as the cam 73 rotates, the position where the pressing portion 77 of the cam 73 presses the bent portion 41 on the right side of the support member 37 continuously changes, and the above-described peeling claw 44 slides in the left-right direction ( The slide along the longitudinal direction of the fixing roller 31 is continuously repeated. That is, the rotational driving force of the driving means of the fixing roller 31 is converted into a linear driving force in the longitudinal direction of the fixing roller 31, and the peeling claw 44 moves back and forth linearly by this driving force.

  On the other hand, when returning from the image forming state to the standby state, the rotation of the fixing roller rotating gear 33, the idle gear 34, the first connecting gear 66, the second connecting gear 67, the worm gear 72, and the cam 73 is accompanied. It stops, and the slide of the peeling claw 44 also stops.

  In this embodiment, since the peeling claw 44 is slid by the slide mechanism 50 as described above, the contact position between the peeling claw 44 and the fixing roller 31 can be changed, and local wear of the fixing roller 31 is reliably ensured. And the durability of the fixing roller 31 can be improved. For this reason, it is possible to prevent the image defect due to the above-mentioned local wear.

  Further, since the slide mechanism 50 can be attached to and detached from the fixing device main body 22, when the slide mechanism 50 breaks down, the slide mechanism 50 can be detached from the fixing device main body 22 and repaired, thereby improving maintainability. It becomes possible to make it. Further, when the durability of the fixing roller 31 can be sufficiently maintained without sliding the peeling claw 44, the paper peeling mechanism can be used with the slide mechanism 50 removed from the fixing device main body 22. Accordingly, the configuration of the sheet peeling mechanism and the fixing device 18 can be simplified to save space.

  Further, since the slide mechanism 50 can be attached to and detached from the fixing device main body 22 as described above, for example, in some models, the slide mechanism 50 is detached from the fixing device main body 22 and the fixing device 18 is made compact, so Then, the slide mechanism 50 can be mounted on the fixing device main body 22 to reliably prevent local wear of the fixing roller 31. That is, unit sharing can be achieved in models for various purposes. For this reason, effects such as reduction in the number of stocks, reduction in mold costs, and cost reduction are expected.

  Further, the slide mechanism 50 is realized with a simple configuration using the cam 73. Further, since the cam 73 can be attached to and detached from the holder 51, the cam 73 attached to the holder 51 can be easily replaced with another cam 73 having a different shape and outer diameter. It becomes possible to change the slide speed and slide width of the claw 44. That is, it is possible to manufacture the sheet peeling mechanism and the fixing device 18 having various specifications only by exchanging the cam 73 as one component.

  Further, the hook 53 provided at the rear end of the holder 51 is engaged with the protruding piece 26 of the fixing device main body 22, and the through hole 57 of the holder 51 and the screw hole 30 of the fixing device main body 22 are fastened by the screw 58. ing. Therefore, the holder 51 can be firmly fixed to the fixing device main body 22 with a simple configuration.

  Further, since the cam 73 is connected to the fixing roller rotating gear 33, the peeling claw 44 can be automatically slid by the driving means of the fixing roller 31, and the sliding operation of the peeling claw 44 is performed manually. Compared to the above, it is possible to reduce the work burden on the user and service person.

  In this embodiment, the case where the peeling claw 44 is automatically slid by the driving unit of the fixing roller 31 has been described. However, in another different embodiment, the peeling claw 44 may be manually slid.

  In the present embodiment, the case where the pressing portion 77 having an elliptical shape in plan view is formed on the cam 73 has been described, but in another different embodiment, the pressing portion 77 having a regular circular shape in plan view is formed on the cam 73. May be. In this case, in order to press the support member 37 with the rotation of the cam 73, it is necessary to provide the rotation center of the cam 73 at a position eccentric from the center of the perfect circle. In other different embodiments, a hexagonal or octagonal cam may be used.

  In this embodiment, the case where the four peeling claws 44 are brought into contact with the peripheral surface of the fixing roller 31 has been described. However, in other different embodiments, the number of peeling claws 44 other than four, such as two or six. May be brought into contact with the peripheral surface of the fixing roller 31.

  In this embodiment, the heater 32 is used as a means for heating the fixing roller 31. However, in another different embodiment, the fixing roller 31 may be heated using another heating means such as an IH fixing unit.

  In the present embodiment, the case where the present invention is applied to the printer 1 has been described. However, in another different embodiment, the present invention can also be applied to other image forming apparatuses such as a copying machine, a facsimile, and a digital multifunction peripheral. It is.

<Second Embodiment>
Next, details of the printer 1 according to the second embodiment will be described with reference to FIGS. FIG. 11 is a perspective view from the right front side showing the slide mechanism in the fixing device of the printer according to the second embodiment of the present invention. 12A is a side view showing a state in which the first mounting portion is attached to the holder support portion, and FIG. 12B is a side view showing the fixing device of the printer according to the second embodiment of the present invention. It is a side view which shows the state which attached the 2 attaching part to the holder support part. FIG. 13A is a perspective view showing a state where the first pressing portion of the cam is in contact with the support member in the fixing device of the printer according to the second embodiment of the present invention, and FIG. These are perspective views which show the state which the 2nd press part of a cam is contacting the support member.

  Since the configuration other than the holder and cam provided in the slide mechanism of the fixing device is the same as that of the first embodiment, the same reference numerals as those of the first embodiment are given to the respective parts in the drawings, and the description will be made. Omitted.

  As shown in FIG. 11, the holder 81 of the slide mechanism 80 has a box shape with an upper surface opened. A shaft hole 84 is drilled in the left-right direction at the front part of the left and right side plates 82, 83 of the holder 81. A shaft hole 85 is formed in the left and right direction at the rear part of the left and right side plates 82 and 83 of the holder 81. Step portions 86 are provided at the rear portion of the left side plate 82 of the holder 81 and the front portion of the right side plate 83, respectively.

  At the front end of the left side plate 82 and the rear end of the right side plate 83 of the holder 81, hooks 87 as holder side engaging portions are provided. About the shape of the hook 87, since it is the same as that of 1st Embodiment, the same number as 1st Embodiment is attached | subjected to each part on drawing, and description is abbreviate | omitted.

  Through holes 90 as holder-side fastening portions are formed in the right front end portion and the left rear end portion of the bottom plate 88 of the holder 81, respectively. A stepped portion 91 is provided in the front portion of the bottom plate 88 of the holder 81 along the left-right direction. Therefore, as shown in FIG. 12, a first attachment portion 92 is formed in front of the step portion 91 and a second attachment portion 93 is formed behind the step portion 91 at the bottom of the holder 81. The second attachment portion 93 is located below the first attachment portion 92. Note that an arrow h in FIG. 12A indicates the height of the stepped portion 91.

  As is clear from the above description, the portions of the holder 81 other than the stepped portion 91 and the mounting portions 92 and 93 are symmetric with respect to the vertical line X (see FIG. 11) passing through the center of the cam 94. Although not shown, the round hole, the long hole, and the insertion opening (all refer to the first embodiment) provided on the bottom surface of the holder 81 are also provided at positions that are symmetrical about the vertical line X, respectively. It has been.

  The cam 94 is rotatably supported by the second mounting portion 93 of the holder 81. A drive gear 95 that meshes with the worm gear 72 is provided on the upper portion of the cam 94. As shown in FIG. 13, below the drive gear 95, an elliptical first pressing portion 96 is provided integrally with the drive gear 95. Below the first pressing portion 96, an elliptical second pressing portion 97 is provided integrally with the drive gear 95 and the first pressing portion 96. The second pressing part 97 is smaller than the first pressing part 96 and is formed in a shape different from the first pressing part 96.

  When the first mounting portion 92 of the holder 81 is attached to the holder support portion 28 of the fixing device main body 22 as shown in FIG. 12A in the configuration configured as described above, as shown in FIG. Further, the first pressing portion 96 of the cam 94 presses the bent portion 41 on the right side of the support member 37. Therefore, each peeling claw 44 attached to the support member 37 slides at a sliding speed and a sliding width corresponding to the shape and outer diameter of the first pressing portion 96 of the cam 94.

  From this state, the holder 81 is detached from the fixing device main body 22, the holder 81 is inverted around the vertical line X (see FIG. 11), and the second mounting portion 93 of the holder 81 is attached to the holder support portion 28 of the fixing device main body 22. Is attached, the position of the cam 94 rises by the height h of the stepped portion 91 (see FIG. 12B). Accordingly, as shown in FIG. 13B, the second pressing portion 97 of the cam 94 presses the bent portion 41 on the right side of the support member 37. Therefore, each peeling claw 44 attached to the support member 37 slides at a slide speed and a slide width corresponding to the shape and outer diameter of the second pressing portion 97 of the cam 94.

  In the present embodiment, as described above, the portion of the cam 94 that presses the support member 37 is changed only by changing the mounting posture of the holder 51 with respect to the fixing device main body 22, and the slide speed and slide width of the peeling claw 44 are changed. Is possible. Therefore, it is possible to manufacture a sheet peeling mechanism and a fixing device 18 having a plurality of specifications without adding or replacing members.

  In the present embodiment, the case where the first mounting portion 92 and the second mounting portion 93 are provided in the holder 81 and the first pressing portion 96 and the second pressing portion 97 are provided in the cam 94 has been described. That is, in this embodiment, the case where the part which presses the support member 37 in the cam 94 is changed in two steps has been described. On the other hand, in another different embodiment, the holder 81 is provided with three or more attachment portions 93 and the cam 94 is provided with three or more pressing portions, and the portion of the cam 94 that presses the support member 37 is divided into three or more stages. It may be changed.

  In the first and second embodiments, the case where the peeling claw 44 is brought into contact with the fixing roller 31 provided in the fixing device 18 has been described. On the other hand, in another different embodiment, for example, a peeling member such as the peeling claw 44 may be brought into contact with another different rotating member such as the photosensitive drum 10.

1 Printer (image forming device)
18 Fixing device 22 Fixing device main body 26 Projection piece (main body side engaging portion)
30 Screw hole (Body side fastening part)
31 Fixing roller (rotating member)
37 support member 42 peeling claw support plate 43 guide plate 44 peeling claw (peeling member)
50 Slide mechanism 51 Holder 53 Hook (holder side engaging part)
57 Insertion hole (holder side fastening part)
62 Boss 73 Cam 74 Boss receiving part 75 Mounting screw (Mounting member)
81 holder 94 cam

Claims (6)

A main body rotatably supporting the rotating member;
A peeling member that contacts the rotating member and peels the paper from the rotating member;
A sliding mechanism for sliding the peeling member along the longitudinal direction of the rotating member,
A support member that supports the peeling member is supported by the main body so as to be slidable along the longitudinal direction of the rotating member,
The slide mechanism is
A holder detachably attached to the main body,
A cam that is rotatably supported by the holder, presses the supporting member along the longitudinal direction of the rotating member along with the rotation, and is provided with a drive gear ;
A worm gear that directly meshes with the drive gear, and a connection gear that is rotatably supported by the holder, and is detachably provided to the main body,
The cam is provided above the rotary member, the rotation axis of the cam state, and are perpendicular to the rotation axis of the longitudinal direction and the connecting gear of said rotary member,
A sheet peeling mechanism , wherein only the cam is removable from the holder while the connection gear is attached to the holder . A support plate fixed to the support member and having a pair of guide plates projecting therefrom;
The sheet peeling mechanism according to claim 1, wherein the peeling member is disposed between the pair of guide plates. The holder is provided with a cylindrical boss projecting,
The cam is provided with a cylindrical boss receiving portion,
By fastening an attachment member to the boss with the boss receiving portion engaged with the boss, the cam is detachably attached to the holder, and the cam is rotatably supported by the holder. The paper peeling mechanism according to claim 1, wherein the paper peeling mechanism is provided. The main body is provided with a main body side engaging portion and a main body side fastening portion,
The holder is provided with a holder side engaging portion engageable with the main body side engaging portion at one end portion, and a holder side fastening portion capable of being fastened with the main body side fastening portion is opposite to the one end portion. The sheet peeling mechanism according to claim 1, wherein the sheet peeling mechanism is provided at an end portion. A fixing device comprising the sheet peeling mechanism according to claim 1,
The fixing device, wherein the rotating member is a fixing roller for fixing a toner image on a sheet.   An image forming apparatus comprising the sheet peeling mechanism according to claim 1 or the fixing device according to claim 5.