JP5893425B2 - Fixing apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a fixing device and an image forming apparatus that peel off a sheet conveyed by a rotating member with a peeling plate.

  In an image forming apparatus such as an electrophotographic method, an electrostatic recording method, or a magnetic photographic method, a fixing device is applied. The fixing device sandwiches a sheet on which a toner image is formed between a pair of fixing rollers and heats the sheet. And pressurizing to fix the toner image on the paper. In such a fixing device, when the sheet is wound around the fixing roller and is not peeled off, a conveyance failure occurs. Therefore, the sheet is peeled off at the tip of a peeling plate disposed in the vicinity of the fixing roller.

  In the fixing device described above, when the distance between the peeling plate and the fixing roller is large, the leading edge of the peeling plate does not contact the paper wound around the fixing roller, and the paper may not be peeled off. Therefore, when the peeling plate is brought close to the fixing roller, the leading edge of the peeling plate may come into contact with the fixing roller, and the surface of the fixing roller may be damaged by the peeling plate, thereby causing image smearing.

  By the way, the thin plate-like release plate is positioned from the surface of the fixing roller by being attached to a substrate having high rigidity fixed to a housing or the like. Here, if the leading edge of the peeling plate is wavy, the gap between the fixing roller and the fixing roller varies. Therefore, it is necessary to increase the distance in consideration of the variation. In addition, when attaching a release plate to a base material using an adhesive, the thickness of the adhesive to be applied varies, causing the problem of the release plate undulating, and heating and cooling being repeated. Thus, there is a problem that the peeling plate is peeled off from the base material.

  Therefore, as a method of joining the release plate without using an adhesive, it has been studied to form a release member by joining a fluororesin sheet subjected to plasma etching to a base material by thermocompression bonding (for example, Patent Documents). 1).

JP 2007-34017 A

  In the fixing device using the peeling member described in Patent Document 1 described above, the fluororesin sheet is attached to the base material. However, when the fluororesin sheet is formed, the fluororesin sheet may wave. Moreover, since the base material is wavy due to the limit of the processing accuracy of the base material, there is a problem that the bonded fluororesin sheet is waved.

  The present invention has been made in order to solve the above-described problems. By stretching the release plate with the urging member, the undulation at the tip of the release plate is eliminated, and the release plate and the rotating member are spaced at a constant interval. It is an object of the present invention to provide a fixing device and an image forming apparatus that can be reliably positioned in such a state.

  A fixing device according to the present invention includes a rotating member that conveys a sheet, a pressure roller that presses the sheet while being in pressure contact with the rotating member, and a peeling plate whose tip is positioned with respect to the peripheral surface of the rotating member. A fixing device that holds the sheet between the rotating member and the pressure roller, fixes a toner image formed on the sheet, and peels the sheet conveyed by the rotating member with the release plate And when the direction parallel to the rotation axis of the rotating member is the axial direction, it comprises a biasing member attached to any end of the axial direction of the peeling plate, the tip of the peeling plate is The urging member is arranged along the axial direction, and the urging member urges the peeling plate in the direction of extending along the axial direction.

  According to this configuration, by extending the peeling plate in the axial direction, the undulation at the tip of the peeling plate is eliminated, and the peeling plate and the rotating member can be reliably positioned in a state of being at a constant interval. In other words, since the tip of the peeling plate is wavy, there is a possibility that the gap between the rotating member and the peeling plate may come into contact with the rotating member. Therefore, the gap needs to be increased in consideration of the variation. However, by making the distance between the peeling plate and the rotating member constant, the peeling plate can be brought as close to the rotating member as possible.

  In the fixing device according to the present invention, the release plate has one end in the axial direction positioned and fixed in the axial direction, and the biasing member is attached to the other end in the axial direction. It is characterized by that.

  According to this configuration, by fixing one end portion of the peeling plate, the number of urging members can be limited to one and the cost can be reduced. Moreover, the biasing force applied to the peeling plate can be easily adjusted by using one biasing member. That is, when the urging members are attached to both ends, the urging forces applied from each of them act so as to cancel each other out, so it is necessary to adjust the balance so that the urging member is 1 If so, there is no need to consider the balance of urging forces.

  The fixing device according to the present invention includes a holding member that holds the peeling plate in contact with a back surface of the peeling plate facing the rotating member and a circumferential surface of the rotating member.

  According to this configuration, the holding member is in contact with the rotating member and the peeling plate, and the separation plate is held so as not to approach the rotating member by fixing the interval between the rotating member and the peeling plate. It is possible to reliably prevent the tip from coming into contact with the rotating member.

  In the fixing device according to the present invention, the holding member has a protrusion protruding toward the release plate, and the release plate includes a plate restriction hole into which the protrusion is inserted, and the protrusion Is characterized in that movement of the tip of the peeling plate in a direction approaching the rotating member is restricted.

  According to this structure, it can prevent that a peeling plate contacts a rotation member by forming a projection part. Since the peeling plate is held by the holding member, it does not move in the direction toward the holding member, but may move in the other direction if no protrusion is formed. However, the direction in which the peeling plate moves can be restricted by providing the protrusion inserted into the plate restricting hole.

  In the fixing device according to the present invention, the plate restricting hole is formed to have a larger width in the axial direction than the protruding portion.

  According to this configuration, the peeling plate can be extended without moving the holding member by forming the plate restricting hole with a larger width in the axial direction than the protruding portion.

  In the fixing device according to the present invention, the holding member is configured to be in contact with the end portion in the axial direction of the rotating member.

  According to this configuration, the portion where the holding member is in contact with the rotating member is an end portion which is a non-image region that does not affect the fixing of the toner image, thereby avoiding image smearing.

  In the fixing device according to the present invention, the holding member is provided with a sliding portion at a contact point with the rotating member, and the sliding portion is formed of a slidable material.

  According to this configuration, it is possible to prevent the rotating member from being damaged by providing the sliding portion having sliding properties.

  In the fixing device according to the present invention, a direction in which the biasing member is biased is inclined toward the holding member side with respect to the axial direction.

  According to this configuration, since the release plate is biased so as to press the holding member, the release plate and the holding member are in close contact with each other, and the release plate can be reliably held.

  An image forming apparatus according to the present invention includes the fixing device according to the present invention.

  According to this configuration, by providing the fixing device according to the present invention, the same effects as the fixing device according to the present invention are exhibited.

According to the present invention, by stretching the release plate in the axial direction, the undulation at the tip of the release plate is eliminated, and the release plate and the rotating member can be reliably positioned with a constant interval. In addition, since the holding member is in contact with the rotating member and the peeling plate and the distance between the rotating member and the peeling plate is fixed, the peeling plate is held so as not to approach the rotating member, so the tip of the peeling plate rotates. It can prevent reliably contacting a member.

1 is a schematic cross-sectional view of an image forming apparatus according to an embodiment of the present invention. 1 is a side view illustrating a schematic configuration of a fixing device according to an embodiment of the present invention. FIG. 3 is a top view of the fixing device shown in FIG. 2. FIG. 4 is an enlarged cross-sectional view mainly showing a peeling plate in a cross section taken along arrows AA in FIG. 3. FIG. 4 is an enlarged cross-sectional view mainly showing a peeling plate in a cross section taken along arrows BB in FIG. 3. It is a front view which extracts and shows the paper peeling part shown in FIG. FIG. 5B is a cross-sectional view taken along arrows CC in FIG. 5A. It is a front view which extracts and shows the modification 1 of a paper peeling part. It is sectional drawing in the arrow DD of FIG. 6A. It is a front view which extracts and shows the modification 2 of a paper peeling part. It is sectional drawing in the arrow EE of FIG. 7A.

  Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic sectional view of an image forming apparatus according to an embodiment of the present invention.

  The image forming apparatus 1 includes an optical scanning device 11, a developing device 12, a photosensitive drum 13, a drum cleaning device 14, a charger 15, an intermediate transfer belt device 16, a fixing device 17, a paper transport path S, a paper feed cassette 18, and A paper discharge tray 19 is provided, and a color image indicated by the image data is formed on a sheet.

  A color image is formed by overlapping toner images of black (K), cyan (C), magenta (M), and yellow (Y). For this reason, the developing device 12, the photoconductor drum 13, the drum cleaning device 14, and the charger 15 are provided four by four so as to form four types of toner images corresponding to the respective colors. Four image stations Pa, Pb, Pc, and Pd are configured in association with magenta and yellow.

  The photosensitive drum 13 has a photosensitive layer on the surface, and the surface is cleaned by the drum cleaning device 14 and then uniformly charged to a predetermined potential by the charger 15. The optical scanning device 11 is a laser scanning unit (LSU) provided with a laser diode and a reflection mirror, and scans the surface of the photosensitive drum 13 with a laser beam to generate an electrostatic latent image corresponding to image data on the photosensitive member. Write on the surface of the drum 13. The developing device 12 develops the electrostatic latent image written on the surface of the photosensitive drum 13 with toner, and forms a toner image on the surface of the photosensitive drum 13.

  The intermediate transfer belt device 16 is disposed above the photosensitive drum 13 and includes an intermediate transfer belt 21, an intermediate transfer belt driving roller 22, a driven roller 23, four intermediate transfer rollers 24, and a belt cleaning device 25. Yes.

  The intermediate transfer belt 21 has an endless belt shape, and the intermediate transfer belt driving roller 22, the driven roller 23, and the four intermediate transfer rollers 24 stretch and support the intermediate transfer belt 21, and the intermediate transfer belt 21 is supported. Move around in the direction of arrow F.

  The intermediate transfer roller 24 is rotatably supported in the vicinity of the intermediate transfer belt 21 and is pressed against the photosensitive drum 13 via the intermediate transfer belt 21. The intermediate transfer roller 24 is a roller having a metal shaft (for example, a stainless shaft) as a base and a surface covered with a conductive elastic material (for example, EPDM, urethane foam, or the like). The intermediate transfer roller 24 is applied with a high-voltage transfer bias (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) in order to transfer the toner image, and the high voltage is applied by the elastic material. Applied uniformly to the paper. The toner image formed on the surface of the photosensitive drum 13 is sequentially transferred to the intermediate transfer belt 21, and a color toner image is formed by overlapping each color toner image.

  A secondary transfer roller 26 a of the secondary transfer device 26 is pressed against the intermediate transfer belt driving roller 22 via the intermediate transfer belt 21. The secondary transfer roller 26a is applied with a voltage (a high voltage having a polarity (+) opposite to the toner charging polarity (-)) for transferring the toner image of each color on the intermediate transfer belt 21 onto the sheet. . The toner image formed on the intermediate transfer belt 21 is transferred to a sheet in a nip area between the intermediate transfer belt 21 and the secondary transfer roller 26a, and the sheet on which the toner image is transferred passes through the sheet conveyance path S. It is conveyed to the fixing device 17.

  When the sheet passes, the fixing device 17 heats and presses the sheet with a roller or the like to fix the toner image transferred to the sheet. Thereafter, the paper is discharged via a paper discharge roller 34 and stacked on a paper discharge tray 37. The fixing device 17 will be described in detail with reference to FIGS. 2 and 3 described later.

  The belt cleaning device 25 is provided with a cleaning blade that removes residual toner by contacting the surface of the intermediate transfer belt 21 as a cleaning member. The toner remaining on the surface of the intermediate transfer belt 21 without being transferred to the paper is removed and collected by the belt cleaning device 25.

  A paper feed cassette 18 for supplying paper to the paper transport path S is provided at the lower part of the image forming apparatus 1. A paper pick-up roller 31 is provided at the end of the paper feed cassette 18, and the paper pick-up roller 31 pulls out the paper one by one from the paper feed cassette 18 and sends it out to the paper transport path S.

  A sheet registration roller 32, a fixing device 17, a transport roller 33, and a paper discharge roller 34 are arranged along the paper transport path S. The transport roller 33 is a small roller for transporting paper, and a plurality of sets are provided. The sheet registration roller 32 temporarily stops the conveyed sheet, aligns the leading edge of the sheet, and rotates the photosensitive drum 13 and the intermediate transfer belt 21 so that the toner image on the intermediate transfer belt 21 is transferred to the sheet. The paper is transported in a timely manner to match.

  Next, a fixing device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 2 is a side view showing a schematic configuration of the fixing device according to the embodiment of the present invention, and FIG. 3 is a top view of the fixing device shown in FIG.

  In the fixing device 17 according to the embodiment of the present invention, a rotating member (for example, a fixing belt 44 described later) that conveys a sheet, a pressure roller 41 that presses against the rotating member and pressurizes the sheet, and a tip 51a rotate. A separation plate 51 that is positioned with respect to the peripheral surface of the member, and sandwiches the sheet by the rotating member and the pressure roller 41 to fix the toner image formed on the sheet, and is conveyed by the rotating member Is peeled off by the peeling plate 51. The fixing device 17 is attached to either end of the peeling plate 51 in the axial direction X, where the axial direction X is a direction parallel to the rotating shaft of the rotating member (for example, a fixing rotating shaft 42a described later). The urging member 52 is provided, the tip 51a of the peeling plate 51 is disposed along the axial direction X, and the urging member 52 urges the peeling plate 51 along the axial direction X in a direction in which the peeling plate 51 extends.

  According to this configuration, by extending the peeling plate 51 in the axial direction X, the undulation at the tip of the peeling plate 51 is eliminated, and the peeling plate 51 and the rotating member can be positioned reliably at a constant interval. it can. That is, when the tip 51a of the peeling plate 51 is undulated, there is a possibility that the spacing between the rotating member and the peeling plate 51 may come into contact with the rotating member. Therefore, it is necessary to increase the spacing in consideration of the variation. However, by making the distance between the peeling plate 51 and the rotating member constant, the peeling plate 51 can be brought as close to the rotating member as possible.

  Specifically, the fixing device 17 is a belt fixing method, and includes a pressure roller 41, a fixing roller 42, a heating roller 43, a fixing belt 44, a thermistor 45, and a sheet peeling unit 50.

  The pressure roller 41 is a three-layered roller in which a thin elastic layer is provided on the outer peripheral surface of a hollow pressure rotating shaft 41a and a release layer is formed on the outer peripheral surface of the elastic layer.

  The fixing roller 42 is a roller in which an elastic layer is provided on the outer peripheral surface of a hollow fixing rotating shaft 42a. Note that the elastic layer of the fixing roller 42 is formed to be sufficiently thick.

  The heating roller 43 is a roller provided with a surface layer on the outer peripheral surface of a hollow heating rotating shaft 43a. A heater lamp 46 (halogen lamp) serving as a heat source for heating the heating roller 43 is provided inside the heating rotating shaft 43a.

  The fixing belt 44 is an endless belt made of a material having a release layer on the outer peripheral surface and excellent in thermal conductivity. The fixing belt 44 is stretched between the fixing roller 42 and the heating roller 43.

  The pressure roller 41 is pressed against the fixing roller 42 via the fixing belt 44, and the elastic layer of the fixing roller 42 is formed sufficiently thick. The pressure roller 41 and the fixing roller 42 are in a pressure contact state, and a wide nip area N is formed between the pressure roller 41 and the fixing roller 42.

  The pressure rotating shaft 41a is connected to a driving unit (not shown) and drives the pressure roller 41 to rotate. The present invention is not limited to this, and driving means may be connected to the fixing rotation shaft 42a or the heating rotation shaft 43a. Further, a plurality of the pressure rotating shaft 41a, the fixing rotating shaft 42a, and the heating rotating shaft 43a may be connected to a driving unit and rotated in conjunction with each other. The pressure rotating shaft 41a, the fixing rotating shaft 42a, and the heating rotating shaft 43a are rotatably supported by a housing (not shown) or the like, and are arranged in parallel with the axial direction X, respectively.

  When the pressure roller 41 and the fixing roller 42 are brought into a pressure contact state and the pressure roller 41 is rotationally driven in the direction of the arrow, the fixing belt 44 is driven by the pressure roller 41 and rotates in the direction of the arrow. The fixing roller 42 and the heating roller 43 are driven to rotate in the directions of arrows. At this time, the fixing belt 44 rotates around the nip area N while being heated by the heating roller 43, and the nip area N is heated by the fixing belt 44. Then, when the sheet is conveyed through the nip area N, the toner image is fixed on the sheet by being heated and pressed by the fixing belt 44 and the pressure roller 41.

  The thermistor 45 is arranged slightly spaced from the surface of the fixing belt 44 and detects the surface temperature of the fixing belt 44. Based on the detected surface temperature, energization control of the heater lamp 46 is performed, the surface temperature of the fixing belt 44 is controlled, and the temperature of the nip region N is adjusted to a preset fixing temperature.

  In the present embodiment, the fixing device 17 is a fixing belt type, and the rotating member corresponds to the fixing belt 44, but is not limited thereto, and may be configured without the fixing belt. That is, the pressure roller 41 may be directly pressed against the fixing roller 42. In this case, the rotating member described above corresponds to the fixing roller 42.

  The sheet peeling unit 50 includes a peeling plate 51, an urging member 52, and a holding member 53.

  The peeling plate 51 is a rectangular thin plate, made of stainless steel having a thickness of 0.2 mm, and coated with PTFE (polytetrafluoroethylene). Note that the material of the release plate is not limited to this, and is preferably excellent in heat resistance and rigidity, and polyimide, nickel, or the like may be applied. Further, the peeling plate 51 is arranged with its longitudinal direction coinciding with the axial direction X.

  The peeling plate 51 has one end portion (fixed end portion 51c) in the axial direction X positioned and fixed in the axial direction X, and a biasing member 52 on the other end portion (biasing end portion 51b) in the axial direction X. Is attached. According to this configuration, by fixing one end portion of the peeling plate 51, the biasing member 52 is limited to one and the cost can be reduced. Further, by using one urging member 52, the urging force applied to the peeling plate 51 can be easily adjusted. That is, when the urging members 52 are attached to both ends, the urging forces applied from each of them act so as to cancel each other. If there is one, it is not necessary to consider the balance of urging forces. One end portion (fixed end portion 51c) of the peeling plate 51 may be fixed to, for example, a housing. In the present embodiment, the distance between the peeling plate 51 and the fixing belt 44 is 0.3 ± 0.1 mm. The urging member 52 may be attached to both ends of the peeling plate 51. As a result, the urging force applied to the release plate 51 is increased, so that the straightness of the release plate 51 can be further improved.

  The biasing member 52 is, for example, a spring. The urging member 52 extends the peeling plate 51, particularly the tip 51 a in the axial direction X, thereby improving the straightness in the axial direction X and eliminating the undulation of the peeling plate 51 generated in the manufacturing process. . The urging member 52 has one end attached to the urging end 51b and the other end fixed to a housing or the like.

  The holding member 53 contacts the back surface 51 d of the peeling plate 51 facing the fixing belt 44 and the peripheral surface of the fixing belt 44 and holds the peeling plate 51. According to this configuration, the holding member 53 is in contact with the fixing belt 44 and the peeling plate 51 and the distance between the fixing belt 44 and the peeling plate 51 is fixed, so that the peeling plate 51 is held so as not to approach the fixing belt 44. Therefore, it is possible to reliably prevent the tip 51a of the peeling plate 51 from coming into contact with the fixing belt 44.

  The holding member 53 is formed of a metal such as aluminum, and a holding contact portion 53 a that contacts the peeling plate 51 is provided at an end portion in the axial direction X. Accordingly, the holding member 53 is in contact with the peeling plate 51 only at the end in the axial direction X, and the center of the peeling plate 51 in the axial direction X is separated from the holding member 53. That is, in the present embodiment, the tip 51a of the peeling plate 51 is not in close contact with the holding member 53 over the entire length in the axial direction X. There is no need to consider the wavy.

  The direction in which the biasing member 52 is biased is inclined toward the holding member 53 with respect to the axial direction X. According to this configuration, the release plate 51 is biased so as to press the holding member 53, so that the release plate 51 and the holding member 53 are in close contact with each other, and the release plate 51 can be reliably held. The angle θ for inclining the peeling plate 51 may be appropriately adjusted in the range of 0 degrees to 90 degrees.

  The urging member 52 is preferably attached to the end 51a of the peeling plate 51. As a result, the undulation at the tip 51a can be reliably eliminated.

  4A is an enlarged cross-sectional view mainly showing the peeling plate in the section taken along the arrow AA in FIG. 3, and FIG. 4B is mainly showing the peeling plate in the section taken along the arrow BB in FIG. FIG.

  In the holding member 53, a protruding portion 53b protruding toward the peeling plate 51 is formed in the holding contact portion 53a, and the peeling plate 51 includes a plate regulating hole 51e into which the protruding portion 53b is inserted. The protrusion 53 b restricts the movement of the tip 51 a of the peeling plate 51 in the direction approaching the fixing belt 44. According to this configuration, it is possible to prevent the peeling plate 51 from coming into contact with the fixing belt 44 by forming the protrusion 53b. Since the peeling plate 51 is held by the holding member 53, the peeling plate 51 does not move in the direction toward the holding member 53, but may move in another direction if the protruding portion 53b is not formed. However, the direction in which the peeling plate 51 moves can be restricted by providing the protrusion 53b inserted into the plate restricting hole 51e. In the present embodiment, the plate restricting hole 51e has a shape penetrating the peeling plate 51, but is not limited thereto, and may be a concave portion formed with a small thickness.

  The holding member 53 is configured to be in contact with the end portion of the fixing belt 44 in the axial direction X, and a sliding portion 53 c is provided at a contact point with the fixing belt 44. According to this configuration, the portion where the holding member 53 is in contact with the fixing belt 44 is an end portion that is a non-image region that does not affect the fixing of the toner image, thereby preventing image smearing and the like.

  The sliding portion 53c is desirably formed of a material having slidability. According to this configuration, it is possible to prevent the fixing belt 44 from being damaged by providing the sliding portion 53c having slidability. The sliding part 53c is made of, for example, resin.

  5A is a front view showing the sheet peeling portion shown in FIG. 3 in an extracted manner, and FIG. 5B is a cross-sectional view taken along arrows CC in FIG. 5A.

  In the present embodiment, the plate restricting hole 51e is formed to have a larger width in the axial direction X than the protruding portion 53b. According to this configuration, the separation plate 51 can be extended without moving the holding member 53 by forming the plate restriction hole 51e to have a larger width in the axial direction X than the protrusion 53b.

  Specifically, two plate restricting holes 51e are provided at a predetermined interval in the axial direction X, and two protrusions 53b are formed in accordance with each plate restricting hole 51e.

  Next, Modification 1 and Modification 2 in which the shapes of the peeling plate and the holding member are changed will be described.

  6A is a front view showing a first modified example of the sheet peeling portion, and FIG. 6B is a cross-sectional view taken along arrow DD in FIG. 6A.

  In the first modification, one plate restricting hole 51e (the right plate restricting hole 51e in FIGS. 5A and 5B) is changed to a position fixing hole 51f having the same shape as the protruding portion 53b. Since the protrusion 53b is inserted into the position fixing hole 51f of the release plate 51, the movement of the release plate 51 in the axial direction X is restricted. Note that the position fixing hole 51f is desirably provided at a position close to the end portion (fixed end portion 51c) opposite to the biasing end portion 51b. In other words, the movement in the axial direction X is restricted by the position fixing hole 51f, but the portion from the urging end 51b of the peeling plate 51 to the position fixing hole 51f is expanded, so the portion where the undulation is eliminated. Can be as large as possible.

  Other forms may be applied as a method of fixing the peeling plate 51 and the holding member 53. For example, a recess may be provided instead of the protrusion 53b corresponding to the position fixing hole 51f, and the peeling plate 51 and the holding member 53 may be fixed with a screw or the like.

  FIG. 7A is a front view showing a modified example 2 of the sheet peeling portion, and FIG. 7B is a sectional view taken along arrows EE in FIG. 7A.

  In the second modification, the urging member 52 is attached to the holding member 53. Specifically, the holding member 53 includes a connecting portion 53d that protrudes from the biasing end 51b in the axial direction X. The biasing member 52 has one end attached to the biasing end 51b and the other end connected to the connecting portion. It is attached to 53d.

  It should be noted that the embodiment disclosed herein is illustrative in all respects and does not serve as a basis for limited interpretation. Therefore, the technical scope of the present invention is not interpreted only by the above-described embodiment, but is defined based on the description of the scope of claims. Moreover, all the changes within the meaning and range equivalent to a claim are included.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 17 Fixing device 41 Pressure roller 41a Pressure rotating shaft 42 Fixing roller 42a Fixing rotating shaft 43 Heating roller 43a Heating rotating shaft 44 Fixing belt 50 Paper peeling part 51 Release plate 51a Tip 51b Energizing end part 51c Fixed end 51d Rear surface 51e Plate restricting hole 51f Position fixing hole 52 Energizing member 53 Holding member 53a Holding contact portion 53b Protruding portion 53c Sliding portion 53d Connecting portion

Claims (10)

A rotating member that conveys the paper; a pressure roller that presses the paper while being pressed against the rotating member; and a peeling plate whose tip is positioned with respect to a circumferential surface of the rotating member; A fixing device that sandwiches the paper with a pressure roller, fixes a toner image formed on the paper, and peels the paper conveyed by the rotating member with the release plate;
When the direction parallel to the rotation axis of the rotating member is the axial direction,
A biasing member attached to either end of the axial direction of the release plate ;
A holding member that holds the peeling plate in contact with the back surface of the peeling plate facing the rotating member and the circumferential surface of the rotating member ;
The tip of the peeling plate is disposed along the axial direction,
The biasing member biases the peeling plate in a direction along the axial direction ,
The holding member is formed with a protrusion protruding toward the release plate,
The release plate includes a plate restriction hole into which the protrusion is inserted.
The fixing device , wherein the protruding portion restricts movement of the peeling plate in a direction in which the tip of the peeling plate approaches the rotating member . The fixing device according to claim 1 ,
The fixing device, wherein the plate restricting hole is formed to have a width in the axial direction larger than the protrusion. The fixing device according to claim 1 or 2 , wherein
The fixing device is characterized in that a direction in which the biasing member is biased is inclined toward the holding member with respect to the axial direction. A rotating member that conveys the paper; a pressure roller that presses the paper while being pressed against the rotating member; and a peeling plate whose tip is positioned with respect to a circumferential surface of the rotating member; A fixing device that sandwiches the paper with a pressure roller, fixes a toner image formed on the paper, and peels the paper conveyed by the rotating member with the release plate;
When the direction parallel to the rotation axis of the rotating member is the axial direction,
A biasing member attached to either end of the axial direction of the release plate ;
A holding member that holds the peeling plate in contact with the back surface of the peeling plate facing the rotating member and the circumferential surface of the rotating member ;
The tip of the peeling plate is disposed along the axial direction,
The biasing member biases the peeling plate in a direction along the axial direction ,
The fixing device is characterized in that a direction in which the biasing member is biased is inclined toward the holding member with respect to the axial direction . The fixing device according to claim 4 ,
The holding member is formed with a protrusion protruding toward the release plate,
The release plate includes a plate restriction hole into which the protrusion is inserted.
The fixing device, wherein the protruding portion restricts movement of the peeling plate in a direction in which the tip of the peeling plate approaches the rotating member. The fixing device according to claim 5 ,
The fixing device, wherein the plate restricting hole is formed to have a width in the axial direction larger than the protrusion. A fixing device according to any one of claims 1 to 6 , wherein
The fixing device according to claim 1, wherein one end portion in the axial direction of the peeling plate is positioned and fixed in the axial direction, and the urging member is attached to the other end portion in the axial direction. A fixing device according to any one of claims 1 to 7 ,
The fixing device, wherein the holding member is configured to be in contact with the axial end portion of the rotating member. The fixing device according to claim 8 , wherein
The holding member is provided with a sliding portion at a contact point with the rotating member,
The fixing device according to claim 1, wherein the sliding portion is formed of a slidable material. An image forming apparatus comprising the fixing device according to claim 1 .

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