JP5982771B2 - Fixing device and image forming apparatus using the same - Google Patents

Description

  The present invention relates to a fixing device and an image forming apparatus using the same.

  Conventionally, the image forming apparatus uses a fixing device that forms a toner image on a recording medium such as recording paper and then fixes an unfixed toner image on the recording medium. Some fixing devices use an endless belt member as at least one member for heating or pressurizing a recording medium and apply a lubricant to the inner surface of the endless belt member. As technologies relating to the fixing device, for example, those disclosed in Japanese Patent Application Laid-Open Nos. 2007-279386 and 2010-60697 have already been proposed.

  An image heating apparatus according to Japanese Patent Application Laid-Open No. 2007-279386 includes a belt that heats an image on a recording material at a nip portion, a swinging unit that swings the belt in the width direction, and a width direction of the belt. And a lubricant applying means for applying a lubricant to the inner surface of the belt so that the amount of application on both ends is smaller than that of the central portion.

  The fixing device according to Japanese Patent Application Laid-Open No. 2010-60697 includes a heating roller, an endless fixing belt stretched around a plurality of rollers and in contact with the heating roller, and the fixing belt from the inner peripheral surface side. In the fixing device having a pressing member that presses against the heating roller and forms a fixing nip portion, and a lubricant application unit that applies a lubricant to the inner peripheral surface of the fixing belt, the lubricant application unit includes the lubricant A first lubricant application member having a function of holding and applying the agent and a second lubricant application means, wherein the second lubricant application means is more lubricant than the first lubricant application means. The holding amount is small, and the coating amount per unit area is increased.

JP 2007-279386 A JP 2010-60697 A

  By the way, the problem to be solved by the present invention is to provide a fixing device capable of avoiding the lubricant applied to the inner surface of the endless belt member from going around the outer surface, and an image forming apparatus using the same. There is.

In other words, the invention described in claim 1 is an endless belt constituting at least one of a heating member and a pressure member arranged so as to be pressed against each other at a pressure contact portion through which a recording medium holding an unfixed toner image passes. Members,
Wherein the lubricant applying unit for applying a lubricant to the inner surface of the endless belt member, is disposed at both ends in the direction intersecting with the moving direction of said endless belt member of the lubricant application unit, the endless belt Of the end portions along the direction intersecting the moving direction of the member, the end portion on the lubricant application portion side is obliquely cut away from the lubricant application portion toward the tip portion, and the endless shape The fixing device is provided with a lubricant application member that is divided into a lubricant recovery unit that recovers a lubricant from the inner surface of the belt member and applies the lubricant to the inner surface of the endless belt member.

  According to a second aspect of the present invention, the endless belt member is wound around a plurality of rolls with a predetermined tension, and the endless belt member moves along the axial direction of the roll. The fixing device according to claim 1, further comprising a meandering control unit configured to perform control.

  Further, in the invention described in claim 3, the lubricant application part is disposed in a central part along a direction intersecting a moving direction of the endless belt member, and the lubricant recovery part is 3. The fixing device according to claim 1, wherein the lubricant application unit is disposed on both sides along a direction intersecting a moving direction of the endless belt member via a gap, respectively. is there.

According to a fourth aspect of the present invention, in the lubricant application portion, both end portions along the direction intersecting the moving direction of the endless belt member are moved by the meandering control means. than both end portions of the endless belt member meandering in the direction crossing the direction, according to claim 2, characterized in that it is arranged closer to the center with respect to a direction crossing the moving direction of said endless belt member The fixing device.

Further, the invention described in claim 5 is an image forming means for forming a toner image on a recording medium,
Fixing means for fixing a toner image formed on the recording medium by the image forming means,
An image forming apparatus using the fixing device according to claim 1 as the fixing unit.

According to the first aspect of the present invention, it is possible to avoid the lubricant applied to the inner surface of the endless belt member from entering the outer surface.
According to the first aspect of the invention, even when meandering occurs in the endless belt member, it is possible to avoid the end of the endless belt member from being caught by the lubricant recovery unit. .

  According to the invention described in claim 2, it is possible to avoid the end of the endless belt member from coming into contact with the same position of the roll over which the endless belt member is stretched.

  Furthermore, according to the third aspect of the present invention, it is possible to suppress wear of the same position of the roll over which the endless belt member is wound.

According to the fourth aspect of the present invention, even when meandering occurs in the endless belt, it is possible to reliably prevent the lubricant from going outside the endless belt.

Furthermore, according to the fifth aspect of the present invention, it is possible to avoid the lubricant applied to the inner surface of the endless belt member from going around the outer surface, and the lubricant adheres to the recording medium to cause contamination. Generation | occurrence | production can be suppressed.

FIG. 2 is a schematic diagram showing a main part of the fixing device according to Embodiment 1 of the present invention. 1 is a configuration diagram illustrating an image forming apparatus to which a fixing device according to Embodiment 1 of the present invention is applied. FIG. 1 is a cross-sectional configuration diagram illustrating a fixing device according to a first embodiment of the present invention. It is sectional drawing which shows a lubricant application member. It is a front view which shows a lubricant application member. It is a perspective view which shows a lubricant application member. It is a block diagram which shows the conventional lubricant application member. It is sectional drawing which shows the lubricant application member of the fixing device which concerns on Embodiment 2 of this invention. It is a front view which shows the lubricant application member of the fixing device which concerns on Embodiment 2 of this invention. It is a perspective view which shows the lubricant application member of the fixing device which concerns on Embodiment 2 of this invention. It is a front view which shows the lubricant application member of the fixing device which concerns on Embodiment 3 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1
FIG. 2 shows a tandem full-color image forming apparatus as an image forming apparatus to which the fixing device according to Embodiment 1 of the present invention is applied. The tandem full-color image forming apparatus includes an image reading apparatus and is configured to function as a full-color copying machine. However, the image reading apparatus may be omitted. Further, this full-color image forming apparatus is set to be highly productive, which is the number of recording sheets on which image formation is possible per unit time. For example, per full minute on an A4 size LEF (Long Edge Feed) recording sheet. An image of about 120 to 140 sheets (PPM) can be formed. However, the present invention is not limited to a high-speed tandem image forming apparatus, and can be applied to a single-color image forming apparatus having only one photosensitive drum.

  In FIG. 2, reference numeral 1 denotes a main body of the image forming apparatus, and an image reading device 4 that reads an image of the document 2 is disposed at one upper end (left end in the illustrated example) of the image forming apparatus main body 1. ing. The image reading device 4 illuminates a document 2 placed on a platen glass 5 while being pressed by a document pressing member 3 with a light source 6, and reflects a reflected light image from the document 2 with a full rate mirror 7 and a half rate mirror 8. The image reading element 11 reads the image of the document 2 at a predetermined dot density by performing scanning exposure on the image reading element 11 made of a CCD or the like through a reduction optical system including the image forming lens 10 and the image forming lens 10. It is configured.

  The image of the document 2 read by the image reading device 4 includes, for example, an image processing device as image data of three colors of red (R), green (G), and blue (B) (for example, 8 bits each). The control device 12 determines in advance the image data of the document 2 such as shading correction, position shift correction, brightness / color space conversion, gamma correction, frame deletion, color / moving editing, and the like. The processed image processing is performed. In addition, the image data that has been subjected to the predetermined image processing by the control device 12 as described above is converted into four colors of cyan (C), magenta (M), yellow (Y), and black (K). Converted to image data. Note that the number of colors of image data converted by the control device 12 is not limited to image data of four colors of cyan (C), magenta (M), yellow (Y), and black (K), as will be described later. The color may be converted into six colors including high saturation cyan (HC) and high saturation magenta (HM), and the number of colors is arbitrary. Of course, the image data input to the control device 12 may be sent from a personal computer or the like via a communication line (not shown).

  By the way, this embodiment is configured to include a plurality of image forming means for forming images using toners having different colors.

  That is, inside the image forming apparatus main body 1 according to this embodiment, as shown in FIG. 2, as a plurality of image forming means, cyan (C), magenta (M), high chroma cyan (HC), high chroma magenta Six image forming units 13C, 13M, 13HC, 13HM, 13Y, and 13K corresponding to the colors (HM), yellow (Y), and black (K) are arranged in parallel at regular intervals in the horizontal direction. Has been placed. Note that high chroma cyan (HC) is a cyan color having a cyan hue and having a brighter tone and a relatively higher chroma than the cyan (C) color. High chroma magenta (HM) is a magenta color having a magenta color hue and having a brighter tone and a relatively higher chroma than the magenta (M) color.

  Further, the cyan (C), magenta (M), high chroma cyan (HC), high chroma magenta (HM), yellow (Y), and black (K) image forming units 13C, 13M, 13HC, 13HM, 13Y, The arrangement order of 13K is not limited to that shown in the figure, and may be arranged in a different order. Further, the cyan (C), magenta (M), high chroma cyan (HC), high chroma magenta (HM), yellow (Y), and black (K) image forming units 13C, 13M, 13HC, 13HM, 13Y, 13K is integrally formed as a unit, and is attached to the image forming apparatus main body 1 in a replaceable manner. Note that the image data formed by the high chroma cyan (HC) and high chroma magenta (HM) image forming units 13HC and 13HM is also output from the control device 12 in the same manner as the other color image data.

  These six image forming units 13C, 13M, 13HC, 13HM, 13Y, and 13K are basically configured in the same manner except for the type of toner to be used, as shown in FIG. A photosensitive drum 15 as an image holding member driven at a predetermined rotational speed along the direction of arrow A, a scorotron 16 as primary charging means for uniformly charging the surface of the photosensitive drum 15, An image exposure device 14 serving as a latent image forming unit that exposes an image corresponding to the image data of each color on the surface of the photosensitive drum 15 to form an electrostatic latent image, and an electrostatic latent image formed on the photosensitive drum 15. The image forming apparatus includes a developing device 17 as a developing unit that develops an image with a corresponding color toner, and a cleaning device 18 that cleans transfer residual toner remaining on the surface of the photosensitive drum 15.

  As shown in FIG. 2, the image exposure device 14 modulates the semiconductor laser 19 according to the image data, and emits a laser beam LB from the semiconductor laser 19 according to the image data. The laser beam LB emitted from the semiconductor laser 19 is deflected and scanned by the rotary polygon mirror 22 via the reflecting mirrors 20 and 21, and the focal length is adjusted according to the scanning angle by an unshown f-θ lens. Then, scanning exposure is performed on the photosensitive drum 15 as an image holding member through a plurality of reflecting mirrors 23 and 24 and the like. The image exposure apparatus 14 is not limited to an apparatus that performs image scanning by deflecting and scanning the laser beam LB. For example, an apparatus using an LED eye array in which a large number of LED light emitting elements are arranged may be used. In the case of an image exposure apparatus using a laser beam, the image exposure apparatus can be significantly reduced in size compared with an image exposure apparatus that performs image exposure by deflecting and scanning the laser beam LB, and the entire image forming apparatus is reduced in size. Can be desirable.

  From the control device 12, image forming units 13C, 13M, 13HC for cyan (C), magenta (M), high saturation cyan (HC), high saturation magenta (HM), yellow (Y), and black (K) are provided. The image data of each color is sequentially output to the 13HM, 13Y, and 13K image exposure apparatuses 14C, 14M, 14HC, 14HM, 14Y, and 14K. Laser light LB emitted according to image data from these image exposure apparatuses 14C, 14M, 14HC, 14HM, 14Y, and 14K is mainly applied to the surfaces of the corresponding photosensitive drums 15C, 15M, 15HC, 15HM, 15Y, and 15K. Scanning exposure is performed along the scanning direction (axial direction of the photosensitive drum) to form an electrostatic latent image. The electrostatic latent images formed on the surfaces of the photosensitive drums 15C, 15M, 15HC, 15HM, 15Y, and 15K are converted into cyan (C) and magenta by the developing devices 17C, 17M, 17HC, 17HM, 17Y, and 17K, respectively. (M), high saturation cyan (HC), high saturation magenta (HM), yellow (Y), and black (K) are developed as toner images.

  Cyan (C), magenta (M), high chroma cyan formed in sequence on the photosensitive drums 15C, 15M, 15HC, 15HM, 15Y, and 15K of the image forming units 13C, 13M, 13HC, 13HM, 13Y, and 13K. (HC), high chroma magenta (HM), yellow (Y), and black (K) toner images are below the image forming units 13C, 13M, 13HC, 13HM, 13Y, and 13K, as shown in FIG. Primary transfer rolls 26C, 26M, 26HC, 26HM, 26Y, and 26K are primarily transferred onto the intermediate transfer belt 25 serving as an intermediate transfer member disposed in the state of being superposed on each other.

  The intermediate transfer belt 25 includes a driving roll 27, a driven roll 28, a tension applying roll 29, a driven roll 30, a back support roll 31 of the secondary transfer unit, and a plurality of rolls including a driven roll 32. The photosensitive drums 15C, 15M, 15HC, 15HM, and the like are driven along a direction indicated by an arrow B by a driving roll 27 that is stretched by a predetermined tension and is rotated by a dedicated driving motor that is excellent in constant speed (not shown). It is driven to circulate at a predetermined speed substantially equal to the rotational speeds (circumferential speeds) of 15Y and 15K. As the intermediate transfer belt 25, for example, a flexible synthetic resin film such as polyimide or polyamideimide formed in an endless belt shape is used.

  The cyan (C), magenta (M), high chroma cyan (HC), high chroma magenta (HM), yellow (Y), and black (K) toner images transferred in multiple onto the intermediate transfer belt 25 are as follows: The recording sheet 34 is secondarily transferred onto a recording sheet 34 as a recording medium by a secondary transfer roll 33 that is pressed against the back support roll 31 via the intermediate transfer belt 25, and the toner images of these colors are transferred. Is transported to a fixing device 37 as fixing means according to the embodiment of the present invention by two transport belts 35 and 36. The recording paper 34 onto which the toner images of the respective colors have been transferred is subjected to a fixing process by heat and pressure by a fixing device 37, and then conveyed to a cooling unit 41 via a sheet conveying device 40 to be cooled and curled. In the case of single-sided printing with the curl corrected by the unit 42, the paper is directly discharged onto a discharge tray 43 provided outside the image forming apparatus main body 1.

  As shown in FIG. 2, the recording paper 34 is, for example, of a predetermined size or material from one of a plurality of paper feed trays 44, 45, a paper feed roll 46, and a paper transport roll. The paper is once transported to the resist roll 49 in a state of being separated one by one through the paper transport path 48 formed of the pair 47. The recording paper 34 supplied from one of the paper feed trays 44 and 45 is sent to the secondary transfer position 50 of the intermediate transfer belt 25 by a registration roll 49 that is rotationally driven at a predetermined timing.

  Further, when images are formed on both sides of the recording paper 34 by the image forming apparatus, the recording paper 34 on which the image is fixed on one side by the fixing device 37 is not discharged out of the apparatus as it is, but is switched by the switching gate 51. Then, the conveyance path of the recording paper 34 is switched downward, and the recording paper 34 is temporarily stored in the intermediate tray 53 by the paper feed roller 54 via the reverse paper conveyance path 52. The recording paper 34 accommodated in the intermediate tray 53 is turned upside down through the double-sided paper transport path 55 and the normal paper transport path 48 with the transport direction reversed by the paper feed roller 54. In this state, the sheet is conveyed again to the secondary transfer position 50 of the intermediate transfer belt 25 and an image is formed on the back surface, and then subjected to a fixing process with heat and pressure by the fixing device 37, via the sheet conveying device 40. Then, the paper is conveyed to the cooling unit 41 and cooled, and is discharged onto a discharge tray 43 provided outside the image forming apparatus main body 1 in a state where the curl is corrected by the curl correction unit 42.

  The surface of the photosensitive drum 15 after the primary transfer of the toner image is cleaned by the cleaning device 18. The intermediate transfer belt 25 after the secondary transfer of the toner image is cleaned by a belt cleaning device 56 whose surface is disposed in the vicinity of the drive roll 27.

  In FIG. 2, reference numeral 57 denotes a user interface through which the user inputs image forming conditions and the like.

  FIG. 3 is a cross-sectional configuration diagram showing a fixing device applied to the image forming apparatus configured as described above.

  As shown in FIG. 3, the fixing device 37 includes a heating belt 371 composed of an endless belt member as a heating member, and a pressure roll 372 as a pressure member that comes into pressure contact with the heating belt 371. The heating belt 371 is an outer periphery of a fixing roll 373 as a pressing member disposed on the inner periphery of the heating belt 371, a first stretching roll 374, an internal heating roll 375, and a second stretching roll 376. It is stretched over. Further, the heating belt 371 includes an external heating roll 377 that contacts the outer peripheral surface of the heating belt 371 between the first tension roll 374 and the internal heating roll 375. Further, the heating belt 371 is in pressure contact with the pressure roll 372 in an area wound around the outer periphery of the fixing roll 373, and the fixing nip portion 378 through which the recording paper 34 holding the unfixed toner image T passes. Is configured. Further, on the outer periphery of the fixing roll 373, a peeling pad 379 is disposed on the downstream side along the moving direction of the heating belt 371. The peeling pad 379 uses the “waist” (rigidity) of the recording paper 34 by the curvature of the heating belt 371 to fix the recording paper 34 fixed by the fixing nip 378 where the heating belt 371 and the pressure roll 372 are pressed against each other. In order to peel off from the surface of the heating belt 371, the moving direction of the heating belt 371 is configured to change rapidly.

  Note that, when the recording paper 34 is not peeled from the heating belt 371 using the “waistness” (rigidity) of the recording paper 34 at the outlet of the fixing nip portion 378, the recording paper 34 is exposed from the surface of the heating belt 371. A peeling auxiliary member 380 for forcibly peeling is disposed.

  The heating belt 371 includes, for example, a base layer made of polyimide resin, polyamideimide resin, or the like, an elastic body layer made of silicon rubber or the like laminated on the surface of the base layer, and PFA laminated on the surface of the elastic body layer. It consists of a release layer.

  The fixing roll 373 is made of a cylindrical member made of metal such as aluminum or stainless steel, and is rotationally driven at a predetermined speed along the direction of the arrow by a driving means such as a driving motor (not shown). Inside the fixing roll 373, for example, three halogen lamps 381 are arranged as a heating source, and the surface of the fixing roll 373 is heated to a predetermined temperature (for example, about 150 ° C.), for example. Is done.

  Furthermore, the internal heating roll 375 is made of a cylindrical member made of a metal such as aluminum or stainless steel. Inside the internal heating roll 375, for example, four halogen lamps 382 are arranged as heating sources, and the surface of the internal heating roll 375 has a predetermined temperature (for example, about 190 ° C.), for example. To be heated. The internal heating roll 375 is applied with a force by an elastic member such as a spring (not shown) so as to be displaced from the inside to the outside of the heating belt 371. The heating belt 371 has a predetermined tension (for example, 15 kgf).

  The internal heating roll 375 is provided with meandering control means 383 for controlling meandering for moving the heating belt 371 along the axial direction of the roll over which the heating belt 371 is stretched. The meandering control means 383 moves along the axial direction of the heating belt 371 by moving one end portion along the axial direction of the internal heating roll 375 along the direction intersecting the axial direction of the internal heating roll 375. By controlling the balance of the tension acting on both ends, the heating belt 371 is reciprocated at a predetermined distance (for example, about ± 5 mm) along the axial direction of the internal heating roll 375 at a predetermined timing. It is configured to let you.

  On the other hand, the external heating roll 377 is made of a cylindrical member made of a metal such as aluminum or stainless steel. Inside the external heating roll 377, for example, three halogen lamps 384 are arranged as a heat source, and the surface of the external heating roll 377 has a predetermined temperature (for example, about 190 ° C.), for example. To be heated.

  In this manner, the heating belt 371 has a surface temperature predetermined by the fixing roll 373, the external heating roll 377, and the internal heating roll 375 while being circulated and moved between a plurality of rolls. Heated from inside and outside. Note that the plurality of rolls 373, 374, 375, and 377 that span the heating belt 371 are all longer than the length (width) in the direction in which the length along the axial direction intersects the moving direction of the heating belt 371. It is set long.

  The pressure roll 372 includes a cylindrical member 385 made of metal such as aluminum or stainless steel, an elastic layer 386 made of silicon rubber or the like laminated on the surface of the cylindrical member 385, and laminated on the surface of the elastic layer 386. And a release layer 387 made of PFA or the like.

  Incidentally, the fixing device 37 according to this embodiment includes a lubricant application unit 390 for applying a lubricant to the inner surface of the heating belt 371 in order to suppress wear of the heating belt 371 and the like. As shown in FIG. 3, the lubricant applying unit 390 is disposed between the first tension roll 374 and the external heating roll 377 so as to contact the inner peripheral surface of the heating belt 371. Note that the arrangement of the lubricant application unit 390 is not limited to the position between the first stretching roll 374 and the external heating roll 377, and may be any position as long as it is in contact with the inner peripheral surface of the heating belt 371. For example, it may be disposed between the second tension roll 376 and the fixing roll 373, between the first tension roll 374 and the external heating roll 377, and the second tension roll 376. And the fixing roll 373.

  As shown in FIGS. 4 to 6, the lubricant applying means 390 is a lubricant applying member 391 impregnated with a lubricant made of a non-woven fabric such as Tommy Pyrex (trade name: Shinyodogawa Paper Co., Ltd.) sheet or wick. And a pair of holding members 392 and 393 made of a metal plate or the like that holds the lubricant application member 391 with both front and back surfaces sandwiched therebetween. The holding members 392 and 393 hold the lubricant application member 391 made of a Tommy Pyrex sheet or the like in a folded state and hold both the front and back surfaces of the impregnating member 391 in the longitudinal direction by caulking 394 by burring processing or the like. A plurality of locations are connected and fixed along each other.

  As the lubricant, for example, a silicone oil or the like prepared to a predetermined viscosity is used, and the impregnated member 391 is impregnated by a predetermined amount (about 2 to 5 g).

  Further, the holding members 392 and 393 have their tip portions 392a and 393a bent toward the heating belt 371, and the lubricant application member 391 is predetermined from the tip portions 392a and 393a of the holding members 392 and 393. It is arranged so as to protrude by the specified length. The attachment positions of the holding members 392 and 393 with respect to the heating belt 371 are adjusted so that the tip of the lubricant application member 391 bites into the inner surface of the heating belt 371 by a predetermined amount. FIG. 4 illustrates a state in which the tip of the lubricant application member 391 bites into the heating belt 371 for convenience.

  Further, as shown in FIG. 1, the lubricant application member 391 has a full length L1 set longer than a length L2 along a direction intersecting the moving direction of the heating belt 371, and the lubricant application member 391. Both ends 391a and 391b are arranged so as to be located inside a range L3 in which the heating belt 371 moves by meandering.

  In the conventional fixing device 37, as shown in FIG. 7, the total length L1 ′ of the lubricant applying member 391 is set to a length substantially equal to the length L2 along the direction intersecting the moving direction of the heating belt 371. . Therefore, when the heating belt 371 meanders, the lubricant applied to the inner surface of the heating belt 371 is long along the direction intersecting the moving direction of the heating belt 371 on the surface of the roll that stretches the heating belt 371. The lubricant applied to the region other than the length and applied to the region other than the length along the direction intersecting the moving direction of the heating belt 371 is caused by the end of the heating belt 371 accompanying the meandering of the heating belt 371. It will be scraped and collected by the part. Then, on the surface of the roll over which the heating belt 371 is stretched, when the amount of the lubricant that is scraped and stays at the end of the heating belt 371 reaches a certain amount, the outer surface of the heating belt 371 wraps around, and the heating belt There is a possibility that image quality defects such as “oil stain” may occur due to adhesion to the recording paper 34 heated and fixed by the 371.

  Therefore, as shown in FIG. 1, the lubricant application member 391 according to this embodiment is located in the center portion along the direction intersecting the moving direction of the heating belt 371 and is lubricated with the lubricant. It is divided into a plurality (three in the illustrated example) of a lubricant supply unit 395 as an agent application unit and left and right lubricant recovery units 396 and 397 which are located on both sides and are not impregnated with the lubricant. A gap 398 having a predetermined length is formed between the lubricant supply unit 395 and the lubricant recovery units 396 and 397. In the lubricant supply unit 395, for example, both end portions 395a and 395b along the direction intersecting the moving direction of the heating belt 371 are arranged at the end portions where the heating belt 371 moves along the axial direction of the roll by the meandering control means 383. They are arranged corresponding to each other.

  Further, the end portions 396a and 397a on the center side of the left and right lubricant recovery portions 396 and 397 are inclined so as to be separated from the lubricant supply portion 395 from the end portions held by the holding members 392 and 393 toward the tip portion. Even when the heating belt 371 is meandered, the end portions 371a and 371b of the heating belt 371 are prevented from being caught by the central end portions 396a and 397a of the left and right lubricant recovery portions 396 and 397. Is configured to do.

  In the above configuration, in the image forming apparatus to which the fixing device according to this embodiment is applied, when the sheet immediately after fixing is sucked and conveyed as described below, the guide located on the upstream side in the sheet conveying direction is as follows. It is possible to suppress image defects on the back side of the sheet caused by rubbing between the member and the sheet.

  That is, in the image forming apparatus to which the fixing device 37 according to this embodiment is applied, as shown in FIG. 2, cyan (C), magenta (M), high chroma cyan (HC), high chroma magenta (HM), yellow ( Y) and black (K) image forming portions 13C, 13M, 13HC, 13HM, 13Y, and 13K, corresponding color toner images are formed, and these image forming portions 13C, 13M, 13HC, 13HM, 13Y, The toner images of the respective colors formed on the 13K photosensitive drum 15 are primary-transferred on the intermediate transfer belt 25 in a multiplex manner, and then collectively from the intermediate transfer belt 25 onto the recording paper 34 at the secondary transfer position 50. Secondarily transferred.

  A part or all of the toner images of cyan (C), magenta (M), high chroma cyan (HC), high chroma magenta (HM), yellow (Y), and black (K) are secondarily transferred together. As shown in FIG. 3, the recording sheet 34 is heated and pressurized by a fixing device 37 to fix the unfixed toner image T, and is then conveyed and cooled to a cooling unit 41 by a sheet conveying device 40. In a state where the curl is corrected by the curl correction unit 42, the curl is discharged onto a discharge tray 43 provided outside the image forming apparatus main body 1.

  At that time, as shown in FIG. 3, the fixing device 37 is provided with a lubricant applying means 390 for applying a lubricant to the inner surface of the heating belt 371 in order to suppress wear of the heating belt 371 and the like. As shown in FIG. 1, the lubricant applying means 390 includes a lubricant applying member 391 for applying a lubricant to the inner surface of the heating belt 371. The lubricant applying member 391 is impregnated with a lubricant. The lubricant supply unit 395 is divided into lubricant recovery units 396 and 397 respectively disposed at both ends of the lubricant supply unit 395 in the direction intersecting the moving direction of the heating belt 371 via a gap 398. It is configured.

  Therefore, even if the lubricant applied to the inner surface of the heating belt 371 by the lubricant supply unit 395 meanders so that the heating belt 371 moves in a direction intersecting the moving direction of the heating belt 371 by the meandering control means 383. The lubricant supply units 395 are collected by the lubricant collection units 396 and 397 respectively disposed at both ends in the direction intersecting with the moving direction of the heating belt 371, and it is avoided that the lubricant supply unit 395 wraps around the outer surface of the heating belt 371.

  Therefore, in the fixing device 37, the lubricant applied to the inner surface of the heating belt 371 is prevented from going around the outer surface of the heating belt 371, and the lubricant is applied to the recording paper 34 heated and fixed by the heating belt 371. It is possible to suppress the occurrence of image quality defects such as so-called “oil stain” that adheres.

Embodiment 2
8 to 10 show a second embodiment of the present invention. The same reference numerals are given to the same portions as those in the first embodiment, and in this second embodiment, a lubricant is applied. It is comprised so that the lubricant accommodating member which accommodates the lubricant supplied to a member may be provided.

  That is, in the second embodiment, as shown in FIGS. 8 to 10, a lubricant accommodating member 400 that accommodates the lubricant to be supplied to the lubricant applying member 391 is provided. The lubricant accommodating member 400 is formed by bending a rear end portion 401 of a lubricant application member 391 made of a Tommy Pyrex (trade name: Shinsyukawa Paper Co., Ltd.) sheet from the rear ends of the holding members 392 and 393. It is constructed by accommodating an impregnating member 402 such as a sheet or wick that is made to protrude and impregnated with a lubricant in the rear end portion 401 protruding in this curved shape. ing.

  As shown in FIGS. 9 and 10, the lubricant containing member 400 does not need to be provided over the entire length of the lubricant supply unit 395, and has a predetermined length at the center along the longitudinal direction of the lubricant supply unit 395. What is necessary is just to provide.

  In the second embodiment, since the lubricant application member 391 includes the lubricant accommodating member 400, the lubricant can be stably supplied and applied to the inner peripheral surface of the heating belt 371 over a long period of time. Wear of the inner peripheral surface of the heating belt 371 can be prevented, and the fixing property can be maintained well.

  Since other configurations and operations are the same as those of the first embodiment, description thereof is omitted.

Embodiment 3
FIG. 11 shows a third embodiment of the present invention. The same reference numerals are given to the same portions as those in the first embodiment. In the third embodiment, the inner peripheral surface of the heating belt is shown in FIG. A cleaning member for cleaning the oil is integrally provided on the lubricant application means.

  That is, in the third embodiment, as shown in FIG. 11, of the holding members 392 and 393 of the lubricant applying unit 390, the rear end 392b of one holding member 392 is located upstream along the moving direction of the heating belt 371. It is folded back so as to be substantially parallel to the heating belt 317 on the side, and is made of a nonwoven fabric such as a wick for cleaning the inner peripheral surface of the heating belt 371 on the rear end portion 392c folded back so as to be substantially parallel to the heating belt 371. A cleaning member 410 is integrally attached.

  When configured in this manner, as shown in FIG. 11, the abrasion powder that the heating belt 317 wears adheres to the surface of the lubricant supply unit 395 and the lubricant recovery unit 396 of the lubricant application unit 390 and becomes clogged. Can be suppressed, and the lubricant can be stably supplied by the lubricant supply unit 395 so that the heating belt 317 can run.

  Since other configurations and operations are the same as those of the first embodiment, description thereof is omitted.

  37: fixing device, 371: heating belt, 391: lubricant application member, 395: lubricant supply unit, 396, 397: lubricant recovery unit.

Claims (5)

An endless belt member constituting at least one of a heating member and a pressure member arranged so as to come into pressure contact with each other at a pressure contact portion through which a recording medium holding an unfixed toner image passes;
A lubricant application portion for applying a lubricant to an inner surface of the endless belt member; and an endless belt disposed at both ends of the lubricant application portion along a direction intersecting a moving direction of the endless belt member. Of the end portions along the direction intersecting the moving direction of the member, the end portion on the lubricant application portion side is obliquely cut away from the lubricant application portion toward the tip portion, and the endless shape A fixing device comprising: a lubricant application member that is divided into a lubricant recovery unit that recovers a lubricant from an inner surface of the belt member, and that applies the lubricant to the inner surface of the endless belt member.   The endless belt member is wound around a plurality of rolls with a predetermined tension, and includes meandering control means for controlling the endless belt member to move along the axial direction of the roll. The fixing device according to claim 1.   The lubricant application part is disposed at a central part along a direction intersecting the moving direction of the endless belt member, and the lubricant recovery part is moved by the endless belt member of the lubricant application part. The fixing device according to claim 1, wherein the fixing device is disposed on both sides along a direction intersecting the direction with a gap therebetween. The lubricant application section has the endless belt whose both end portions along the direction intersecting the moving direction of the endless belt member meander in the direction intersecting the moving direction of the endless belt member by the meandering control means. 3. The fixing device according to claim 2 , wherein the fixing device is disposed closer to the center with respect to a direction intersecting a moving direction of the endless belt member than both ends of the member. Image forming means for forming a toner image on a recording medium;
Fixing means for fixing a toner image formed on the recording medium by the image forming means,
An image forming apparatus using the fixing device according to claim 1 as the fixing unit.

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