JP5802601B2 - Fixing apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a fixing device that fixes a toner image on a sheet and an image forming apparatus including the fixing device.

  2. Description of the Related Art Conventionally, an electrophotographic image forming apparatus such as a copying machine or a printer is provided with a fixing device that fixes a toner image (unfixed image) on a sheet. The fixing device includes a heating rotary member (for example, a roller or a belt) that is heated by a heat source, and a pressurizing rotary member (for example, a roller) that is in pressure contact with the heating rotary member. A fixing nip is formed between the rotation member and the pressure rotation member along the sheet conveyance path. As the paper passes through the fixing nip, the toner image is heated and pressurized and fixed on the paper.

  In the fixing device having such a configuration, when the toner image is fixed on the paper in the fixing nip, the water contained in the paper is discharged as water vapor. If the water vapor adheres to a member (for example, a conveyance guide) disposed around the paper conveyance path and condensation occurs, water droplets due to condensation may adhere to the paper and cause image defects. Also, if the paper sucks in water droplets due to condensation, the paper transport stops or the paper transport speed slows down, causing JAM (paper jam).

  In order to solve such a problem, in Patent Document 1, a member (see “paper guide 150”) disposed in the vicinity of the conveyance path is made of plastic to prevent condensation on the member. ing. Further, in Patent Document 2, water vapor generated from the fixing device is removed by providing a dehumidifying member (see “moisture absorbing member 21”) in the conveyance path.

JP 2007-219076 A JP-A-6-035360

  However, it is difficult to sufficiently prevent the occurrence of condensation on this member only by changing the material of the member arranged near the conveyance path as in Patent Document 1. Further, in the prior art described in Patent Document 2, in order to remove moisture absorbed by the dehumidifying member, there is no choice but to wait for the inside of the fixing device to become warm and moisture to spontaneously evaporate. For this reason, in the case of printing a small number of copies that are finished before the inside of the fixing device is sufficiently warmed, it is difficult to sufficiently evaporate the water absorbed by the dehumidifying member, and the water absorbing performance of the dehumidifying member is maintained. However, there was a problem that the volume of the dehumidifying member had to be increased.

  In view of the above circumstances, an object of the present invention is to maintain the water absorption performance of the dehumidifying member without increasing the size of the dehumidifying member, and to prevent dew condensation from occurring in the member disposed near the conveyance path. .

  The fixing device of the present invention is a pressurizing member that forms a fixing nip between a heating rotary member heated by a heat source and the heating rotary member in pressure contact with the heating rotary member and along the sheet conveyance path. A rotating member, and a dehumidifying member disposed along the conveying path downstream of the fixing nip, the dehumidifying member facing the heating rotating member or the pressing rotating member. It is provided to be movable to a position where

  By adopting such a configuration, it becomes possible to efficiently absorb water vapor in the vicinity of the transport path by the dehumidifying member disposed along the transport path. For this reason, it is possible to prevent condensation from occurring on the members arranged in the vicinity of the conveyance path, and it is possible to prevent image defects and JAM due to condensation.

  Further, by moving the dehumidifying member to a position facing the heating rotary member or the pressurizing rotary member, moisture absorbed by the dehumidifying member can be efficiently evaporated by heat from each rotary member. Therefore, the water absorption performance of the dehumidifying member can be maintained without increasing the size of the dehumidifying member.

  The dehumidifying member may be disposed on one or both of the image surface side of the paper on which the toner image is formed and the non-image surface side facing the image surface side.

  By adopting such a configuration, water vapor drifting on the image surface side or non-image surface side of the paper can be efficiently absorbed by the dehumidifying member.

  When the dehumidifying member moves to a position facing the heating rotary member or the pressurizing rotary member, the widest surface of the dehumidifying member faces the outer peripheral surface of the heating rotary member or the pressurizing rotary member. Also good.

  By adopting such a configuration, it becomes possible to more efficiently evaporate the moisture absorbed by the dehumidifying member.

  The fixing device of the present invention may include a conveyance guide disposed along the conveyance path downstream of the fixing nip and along the conveyance path, and the dehumidifying member may be supported by the conveyance guide.

  By adopting such a configuration, it is possible to prevent dew condensation from occurring on the conveyance guide. In addition, by supporting the dehumidifying member with a conveyance guide that is an existing part, the configuration of the fixing device can be simplified as compared with a case where a member that supports the dehumidifying member is separately added.

  The conveyance guide includes a rotation shaft extending along a longitudinal direction of the dehumidification member, and a support portion connected to the rotation shaft and supporting the dehumidification member, and the conveyance guide rotates around the rotation shaft. By doing so, the dehumidifying member may move.

  By adopting such a configuration, the dehumidifying member can be moved with a simple configuration.

  A plurality of the support portions may be provided at intervals in the longitudinal direction of the dehumidifying member.

  By adopting such a configuration, it is possible to improve the air permeability of the transport guide as compared to the case where the support portion has a shape (for example, a plate shape) continuous in the longitudinal direction of the dehumidifying member. Therefore, the water absorption performance of the dehumidifying member can be improved, and the water absorbed by the dehumidifying member can be quickly evaporated.

  At least a part of the support portion may be provided closer to the transport path than the dehumidifying member.

  By adopting such a configuration, it becomes possible to prevent the paper transported along the transport path from coming into contact with the dehumidifying member and to prevent moisture absorbed by the dehumidifying member from adhering to the paper. It becomes possible to do.

  The rotating shaft may be provided at a position farther from the transport path than the dehumidifying member.

  By adopting such a configuration, it is possible to prevent the conveyance of the sheet from being hindered by the rotation shaft.

  The image forming apparatus of the present invention includes any one of the fixing devices described above.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to maintain the water absorption performance of a dehumidification member, without enlarging a dehumidification member, and to prevent that dew condensation generate | occur | produces on the member arrange | positioned in the conveyance path vicinity.

FIG. 2 is an explanatory diagram illustrating an outline of a printer according to an embodiment of the invention. 1 is a cross-sectional view illustrating a fixing device in a printer according to an embodiment of the present invention. FIG. 5 is a perspective view illustrating a first conveyance guide and a first dehumidification pad in the fixing device of the printer according to the embodiment of the present disclosure. FIG. 3 is a side view showing a first conveyance guide, a first dehumidification pad, and a drive motor in the fixing device of the printer according to the embodiment of the present invention. FIG. 4 is a cross-sectional view illustrating a state where each dehumidifying pad has moved to a position facing each roller in the fixing device of the printer according to the embodiment of the present invention.

  First, the overall configuration of a printer 1 as an image forming apparatus will be described with reference to FIG. FIG. 1 is an explanatory diagram showing an outline of a printer according to an embodiment of the present invention. Hereinafter, the front side in FIG. 1 is defined as 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 provided at the bottom of the printer main body 2, and a paper discharge tray is provided at the upper end of the printer main body 2. 4 is provided.

  An exposure unit 5 composed of a laser scanning unit (LSU) is arranged at the upper right part of the printer main body 2, and an image forming unit 6 is provided at the left part of the printer main body 2. The image forming unit 6 is rotatably provided with a photosensitive drum 7 serving as an image carrier. Around the photosensitive drum 7, a charger 8 and a developing unit 10 connected to a toner container 9 are provided. The transfer roller 11 and the cleaning device 12 are arranged along the rotation direction of the photosensitive drum 7 (see arrow X in FIG. 1).

  A paper transport path 13 is provided on the left portion of the printer main body 2 from below to above. A paper feed unit 14 is provided at the upstream end of the conveyance path 13, and a transfer unit 15 configured by the photosensitive drum 7 and the transfer roller 11 is provided at a middle portion of the conveyance path 13, and a downstream part of the conveyance path 13. Is provided with a fixing device 16, and a paper discharge roller pair 17 is provided at the downstream end of the transport path 13.

  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 16 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 7 is charged by the charger 8, exposure corresponding to image data is performed on the photosensitive drum 7 by laser light from the exposure device 5 (see arrow P in FIG. 1). Then, an electrostatic latent image is formed on the surface of the photosensitive drum 7. Next, the developing unit 10 develops the electrostatic latent image into a toner image with the toner supplied from the toner container 9.

  On the other hand, the sheet taken out from the sheet cassette 3 by the sheet feeding unit 14 is conveyed to the transfer unit 15 in synchronization with the above-described image forming operation, and the toner image on the photosensitive drum 7 is transferred to the sheet by the transfer unit 15. Is transcribed. The sheet on which the toner image has been transferred is conveyed downstream in the conveyance path 13 and enters the fixing device 16 where the toner image is fixed on the sheet. The sheet on which the toner image is fixed is discharged to the discharge tray 4 by the discharge roller pair 17. The toner remaining on the photosensitive drum 7 is collected by the cleaning device 12.

  Next, the fixing device 16 will be described in detail with reference to FIGS. FIG. 2 is a cross-sectional view showing the fixing device in the printer according to the embodiment of the present invention. FIG. 3 is a perspective view showing the first conveyance guide and the first dehumidifying pad in the fixing device of the printer according to the embodiment of the present invention. FIG. 4 is a side view showing the first conveyance guide, the first dehumidifying pad, and the drive motor in the fixing device of the printer according to the embodiment of the present invention. FIG. 5 is a cross-sectional view showing a state in which each dehumidifying pad has moved to a position facing each roller in the printer fixing device according to the embodiment of the present invention. In addition, the arrow Fr of FIG.3 and FIG.4 has shown the front side (front side).

  As shown in FIG. 2, the fixing device 16 is opposed to the fixing frame 20 having a box shape, a heat roller 21 as a heating rotating member housed on the lower right side of the fixing frame 20, and the heat roller 21. As a press roller 22 as a pressurizing rotating member housed on the lower left side of the fixing frame 20, a first transport guide 23 disposed above the heat roller 21, and a dehumidifying member supported by the first transport guide 23 The first dehumidifying pad 24, the second transport guide 25 disposed above the press roller 22, the second dehumidifying pad 26 as a dehumidifying member supported by the second transport guide 25, and the transport guides 23, 25. And a pair of conveying rollers 27 disposed above each dehumidifying pad 24, 26.

  A lower end opening 28 is provided in the center of the lower end of the fixing frame 20, and a pair of guide plates 30 protrude from the left and right sides of the lower end opening 28. The upper end of the right guide plate 30 is close to the outer peripheral surface of the heat roller 21, and the upper end of the left guide plate 30 is close to the outer peripheral surface of the press roller 22. An upper end opening 31 is provided at the center of the upper end of the fixing frame 20. An exhaust port 32 is provided at the upper left and upper right of the fixing frame 20.

  The heat roller 21 has a long shape in the front-rear direction. The heat roller 21 includes, for example, a cylindrical core material made of a metal such as aluminum or iron, an elastic layer made of silicon rubber or the like provided around the core material, and a fluorine resin such as PFA that covers the elastic layer. And a release layer. The heat roller 21 is rotatably supported by the fixing frame 20. The heat roller 21 is connected to a driving means (not shown) such as a motor, and the heat roller 21 is rotated by transmitting the rotational driving force of the driving means to the heat roller 21.

  In the internal space of the heat roller 21, a heater 33 as a heat source configured by, for example, a halogen heater or a ceramic heater is accommodated. The heater 33 is configured to generate heat when energized and to heat the heat roller 21.

  Above the heat roller 21, a separation plate 34 is provided below the first conveyance guide 23 and the first dehumidifying pad 24. The separation plate 34 is provided at a position close to or in contact with the outer peripheral surface of the heat roller 21, and can separate the paper attached to the outer peripheral surface of the heat roller 21 from the outer peripheral surface of the heat roller 21. The separation plate 34 may be provided with a separation claw that is in contact with or close to the outer peripheral surface of the heat roller 21.

  The press roller 22 includes, for example, a cylindrical core material made of a metal such as aluminum or iron, an elastic layer made of silicon rubber or the like provided around the core material, and a fluorine resin such as PFA that covers the elastic layer. And a release layer. The press roller 22 is pressed against the heat roller 21 by an urging force of an urging means (not shown), and a fixing nip 35 is formed between the heat roller 21 and the press roller 22. As indicated by arrows in FIG. 2, the press roller 22 is configured to be driven to rotate in the opposite direction to the heat roller 21 as the heat roller 21 rotates.

  The first transport guide 23 is disposed along the transport path 13 above the fixing nip 35 (downstream of the transport path 13). The first transport guide 23 is made of, for example, resin, and as illustrated in FIG. 3, as shown in FIG. 3, a straight rod-shaped rotating shaft 36 and a plurality of (three in this embodiment) support portions connected to the rotating shaft 36. 37.

  The rotating shaft 36 extends along the front-rear direction. The rotating shaft 36 is provided at a position farther from the transport path 13 than the first dehumidifying pad 24. Both front and rear ends of the rotation shaft 36 are rotatably supported by the fixing frame 20. A drive gear 38 is coaxially provided at the front portion of the rotation shaft 36.

  Each support part 37 is arranged at intervals in the front-rear direction and has a rib shape. Each support portion 37 may be formed integrally with the rotation shaft 36 or may be formed separately from the rotation shaft 36.

  Each support portion 37 has a first arm portion 40 that is connected to the rotation shaft 36 at the right end portion and extends in the left-right direction, and a second arm that is bent upward from the left end portion of the first arm portion 40 and extends in the up-down direction. And a third arm portion 42 that is bent rightward from the upper end portion of the second arm portion 41 and extends in the left-right direction.

  A locking projection 43 is provided on the left side of the upper surface of the first arm portion 40. The locking projection 43 includes a guide surface 44 that is inclined to the upper left and has a sharp shape. The second arm portion 41 is disposed on the left side (conveyance path 13 side) with respect to the first dehumidifying pad 24. The third arm portion 42 is formed to have a shorter length in the left-right direction than the first arm portion 40. A locking projection 45 is provided at a position corresponding to the locking projection 43 of the first arm portion 40 at the right end portion of the third arm portion 42. The locking projection 45 includes a guide surface 46 that is inclined to the lower left and has a sharp shape.

  As shown in FIG. 4, a drive motor 47 is provided in front of the first transport guide 23. The drive motor 47 is provided with a motor shaft 48 extending rearward, and a motor gear 50 is coaxially provided on the outer periphery of the motor shaft 48. The motor gear 50 meshes with a drive gear 38 provided on the rotation shaft 36 of the first transport guide 23, and when the motor shaft 48 of the drive motor 47 rotates, this rotation is transmitted via the motor gear 50 and the drive gear 38. Thus, the rotation is transmitted to the rotation shaft 36 of the first conveyance guide 23, and the first conveyance guide 23 rotates about the rotation shaft 36.

  As shown in FIG. 3, the first dehumidifying pad 24 has a rectangular parallelepiped shape elongated in the front-rear direction. The 1st dehumidification pad 24 is comprised by arbitrary materials, such as a pulp, porous ceramics, a synthetic resin, a heat resistant sponge, a polymer absorber, for example.

  The first dehumidifying pad 24 is supported by each support portion 37 of the first transport guide 23. The first dehumidifying pad 24 is sandwiched from the upper and lower sides by the first arm portion 40 and the third arm portion 42 of each support portion 37, and left and right by the second arm portion 41 and the locking projections 43 and 45 of each support portion 37. It is sandwiched from both sides. Thereby, the first dehumidifying pad 24 is fixed to the first transport guide 23.

  As shown in FIG. 2, the second conveyance guide 25 and the second dehumidification pad 26 are symmetrical with the first conveyance guide 23 and the first dehumidification pad 24 around the sheet conveyance path 13. Therefore, the description of the configuration of the second transport guide 25 and the second dehumidifying pad 26 is omitted. However, the first conveyance guide 23 and the first dehumidification pad 24 are arranged on the image surface side of the paper on which the toner image is formed, and the second conveyance guide 25 and the second dehumidification pad 26 are the paper on which the toner image is formed. It is arranged on the back surface (non-image surface) side.

  The conveying roller pair 27 is provided at a position facing the upper end opening 31 of the fixing frame 20 and is rotatably supported by the fixing frame 20. A conveyance nip 49 is provided between the conveyance roller pair 27 along the sheet conveyance path 13.

  In the fixing device 16 configured as described above, when a sheet is conveyed from below along the conveyance path 13, the sheet enters the fixing frame 20 through the lower end opening 28 and passes through the fixing nip 35. To do. As a result, the toner image is fixed on the sheet. The sheet on which the toner image is fixed is conveyed to the upper portion of the fixing frame 20 through the upper end opening 31 by the conveying roller pair 27, guided by the discharge guide pair 51, and conveyed toward the discharge roller pair 17. Thereafter, the paper is discharged to the paper discharge tray 4 by the paper discharge roller pair 17.

  In a state where printing is performed on the paper in this manner (the paper passing state of the printer 1), as shown in FIG. 2, each dehumidifying pad 24, 26 is located above the fixing nip 35 (downstream of the conveyance path 13). The water vapor generated when the toner image is fixed on the paper in the fixing nip 35 is efficiently absorbed by the dehumidifying pads 24 and 26. Therefore, it is possible to prevent dew condensation from occurring in each of the transport guides 23 and 25, and it is possible to prevent image defects and JAM due to dew condensation.

  On the other hand, when printing on the paper is completed and the printer 1 shifts from the paper passing state to the standby state, the drive motor 47 (see FIG. 4) is driven to rotate the motor shaft 48 of the drive motor 47. When the motor shaft 48 rotates in this way, this rotation is transmitted to the rotation shaft 36 of the first conveyance guide 23 via the motor gear 50 and the drive gear 38, and the first conveyance as indicated by the arrow Y in FIG. The guide 23 rotates about the rotation shaft 36. Along with this, as shown in FIG. 5, the first dehumidifying pad 24 supported by the first transport guide 23 moves from a position along the transport path 13 to a position facing the heat roller 21. That is, the first dehumidifying pad 24 moves to a position where the widest surface faces the outer peripheral surface of the heat roller 21. Similarly, as indicated by an arrow Z in FIG. 2, the second conveyance guide 25 rotates about the rotation shaft 36. Along with this, as shown in FIG. 5, the second dehumidifying pad 26 supported by the second transport guide 25 moves from a position along the transport path 13 to a position facing the press roller 22. That is, the second dehumidifying pad 26 moves to a position where the widest surface of the second dehumidifying pad 26 faces the outer peripheral surface of the press roller 22.

  At this time, it is desirable that the entire dehumidifying pads 24 and 26 are as close as possible to the rollers 21 and 22. However, it is not preferable that the dehumidifying pads 24 and 26 come into contact with the rollers 21 and 22 because the dehumidifying pads 24 and 26 may damage the surfaces of the rollers 21 and 22. In the present embodiment, considering that the press roller 22 is smaller in diameter than the heat roller 21, the second dehumidifying pad 26 is moved larger than the first dehumidifying pad 24 (from the first conveyance guide 23). Also, the second transport guide 25 is greatly rotated).

  Thus, each dehumidification pad 24 and 26 opposes each roller 21 and 22, and the water | moisture content absorbed by each dehumidification pad 24 and 26 can be efficiently evaporated with the heat from each roller 21 and 22. . Therefore, even if each dehumidification pad 24 and 26 is not enlarged, the water absorption performance of each dehumidification pad 24 and 26 can be maintained. The water evaporated from the dehumidifying pads 24 and 26 is discharged to the outside of the fixing frame 20 through the exhaust port 32 as shown in FIG.

  In the present embodiment, as described above, since the first dehumidifying pad 24 is supported by the first conveyance guide 23, it is possible to prevent dew condensation from occurring in the first conveyance guide 23. Further, by supporting the first dehumidifying pad 24 by the first conveyance guide 23 which is an existing component, the configuration of the fixing device 16 can be simplified as compared with a case where a member supporting the first dehumidifying pad 24 is separately added. Can be. Further, the first dehumidifying pad 24 can be moved with a simple configuration by rotating the first conveyance guide 23 around the rotation shaft 36.

  The first transport guide 23 is provided with a plurality of rib-like support portions 37 at intervals in the longitudinal direction of the first dehumidifying pad 24 (the front-rear direction in this embodiment). By adopting such a configuration, the air permeability of the first conveyance guide 23 is improved as compared with the case where the support portion 37 has a shape (for example, a plate shape) continuous in the longitudinal direction of the first dehumidifying pad 24. It becomes possible. Therefore, the water absorption performance of the first dehumidifying pad 24 can be improved, and the water absorbed by the first dehumidifying pad 24 can be quickly evaporated.

  Further, since the second arm portion 41 of the support portion 37 is provided closer to the transport path 13 than the first dehumidification pad 24, the sheet transported along the transport path 13 contacts the first dehumidification pad 24. It is possible to prevent the moisture absorbed by the first dehumidifying pad 24 from adhering to the paper. Further, since the rotation shaft 36 of the first conveyance guide 23 is provided at a position farther from the conveyance path 13 than the first dehumidification pad 24, it is possible to prevent the conveyance of the paper from being hindered by the rotation shaft 36. It becomes possible.

  Further, when the first dehumidifying pad 24 moves from a position along the transport path 13 to a position facing the heat roller 21, the widest surface of the first dehumidifying pad 24 is configured to face the outer peripheral surface of the heat roller 21. ing. Therefore, it is possible to more efficiently evaporate the moisture absorbed by the first dehumidifying pad 24.

  In addition, the effect regarding the 1st conveyance guide 23 and the 1st dehumidification pad 24 which were mentioned above is exhibited similarly about the 2nd conveyance guide 25 and the 2nd dehumidification pad 26. FIG.

  Further, a first dehumidifying pad 24 is disposed on the image surface side of the paper on which the toner image is formed, and a second dehumidifying pad 26 is disposed on the back surface (non-image surface) side of the paper on which the toner image is formed. Therefore, water vapor drifting on the image surface side and the non-image surface side of the paper can be efficiently absorbed by the dehumidifying pads 24 and 26. In this embodiment, the dehumidifying pads 24 and 26 are arranged on both the image surface side and the non-image surface side of the paper. However, in other different embodiments, either the image surface side or the non-image surface side of the paper is used. You may arrange a dehumidification pad only in either.

  In the present embodiment, the configuration in which the dehumidifying pads 24 and 26 are disposed on both sides of the transport path 13 has been described. However, in other different embodiments, the dehumidifying pads may be disposed only on one side of the transport path 13. In this case, since the temperature of the heating rotary member is generally higher than that of the pressure rotary member, in order to dry the dehumidification pad faster, it is desirable to dispose the dehumidification pad on the heating rotary member side of the transport path 13. .

  In the present embodiment, the case where the rib-shaped support portion 37 made of resin is used has been described. However, in another different embodiment, the support portion 37 may be formed of a wire or the like.

  In this embodiment, the case where each conveyance guide 23 and 25 rotates around the straight rod-shaped rotation shaft 36 has been described. However, in another different embodiment, the protrusions protrude from the support portions located at both ends in the longitudinal direction of the conveyance guide. It is also possible to configure such that the conveyance guide rotates around the projection by pivotally supporting the projection on the fixing frame. Further, the conveyance guide may be moved using a link mechanism or the like.

  In this embodiment, the case where the heating rotary member is configured by the heat roller 21 and the pressurizing rotary member is configured by the press roller 22 has been described. However, in another different embodiment, the heating rotary member and the like are configured by a belt. You may do it.

  Although the case where the heater 33 is used as the heat source has been described in the present embodiment, other heat sources such as an IH coil may be used in other different embodiments.

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

1 Printer (image forming device)
13 Conveyance path 21 Heat roller (rotating member for heating)
22 Press roller (rotating member for pressurization)
23 1st conveyance guide 24 1st dehumidification pad (dehumidification member)
25 Second transport guide 26 Second dehumidifying pad (dehumidifying member)
33 Heater (heat source)
35 Fixing nip 36 Rotating shaft 37 Support section

Claims (8)

A heating rotary member heated by a heat source;
A pressurizing rotary member that is in pressure contact with the heating rotary member and forms a fixing nip with the heating rotary member along a paper conveyance path;
A dehumidifying member disposed along the transport path on the downstream side of the transport path from the fixing nip,
The dehumidifying member is provided so as to be movable to a position that directly faces the heating rotating member or the pressurizing rotating member, and the image surface side of the paper on which the toner image is formed and the non-image surface facing the image surface side The fixing device is arranged on both sides of the side . When the dehumidifying member moves to a position directly facing the heating rotary member or the pressurizing rotary member, the widest surface of the dehumidifying member faces the outer peripheral surface of the heating rotary member or the pressurizing rotary member. The fixing device according to claim 1 . Than said fusing nip with the conveying guide which is disposed along a transport path in a downstream side of the transport path, according to claim 1 or 2 conveying guide to the dehumidifying member is characterized in that it is supported Fixing device. The transport guide is
A rotating shaft extending along the longitudinal direction of the dehumidifying member;
A support unit coupled to the rotating shaft and supporting the dehumidifying member,
The fixing device according to claim 3 , wherein the dehumidifying member moves as the conveyance guide rotates about the rotation shaft. The fixing device according to claim 4 , wherein a plurality of the support portions are provided at intervals in the longitudinal direction of the dehumidifying member. Said support portion, a fixing device according to claim 4 or 5, characterized in that provided on the transport path side than at least a portion of the dehumidifying member. The rotating shaft fixing device according to any one of claims 4-6, characterized in that provided at a position spaced from the transport path than the dehumidifying member. An image forming apparatus characterized in that it comprises a fixing device according to any one of claims 1-7.