JP6111711B2 - Fixing apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a fixing device for fixing an image on a recording medium and an image forming apparatus including the fixing device, and more particularly, to a fixing device and a fixing device mounted on an image forming apparatus such as a printer, a facsimile machine, or a copying machine. The present invention relates to an image forming apparatus.

  Conventionally, a heat roller fixing device is known as a fixing device used in an image forming apparatus such as a printer, a facsimile machine, or a copying machine. The heat roller fixing device has a heat source such as a heater inside, and is not fixed to the contact nip portion (fixing nip portion) of two rotating bodies (fixing roller and pressure roller) that are pressed against each other and rotated while being heated. The transfer material on which the toner image is placed is passed, where the toner image is melted and fixed on the transfer material.

  On the other hand, due to the increasing demands for energy saving and weight time reduction in recent years, the use of a heating device that uses an endless belt member such as a belt or a thin film instead of a heating roller can reduce the low heat capacity of the fixing device. In addition, the so-called on-demand type fixing device has been widely adopted, which has improved the heat transfer efficiency to the recording medium and greatly shortened the waiting time required for heating (warm-up time and first print time). Yes.

  In this type of fixing device, the nip forming member is moved while being brought into contact with the inner peripheral surface of the belt member, and the nip forming member is pressed against the rotating body via the belt member, so that the belt member and the rotating body are in contact with each other. In this method, a nip portion is formed on the recording medium, and a recording medium is conveyed to the nip portion to fix the toner image on the recording medium.

  Therefore, in such a fixing device, the belt member is pressed against the nip portion forming member by the rotating body, and the belt member is moved while the inner peripheral surface is in contact with the nip portion forming member, thereby forming the belt member and the nip portion. There was a problem that the member was worn.

  Further, in such a fixing device, when the frictional force generated between the belt member and the nip portion forming member increases, the torque of the drive motor that drives the rotating body increases. For this reason, in such a fixing device, the belt member that rotates in a driven manner slips without being driven to rotate with respect to a rotating body that is a driving source, and an unstable brake is applied to the recording medium that passes through the nip portion. Occurrence of wrinkles on the recording medium due to this, generation of a lock that prevents the motor from rotating due to the drive motor being unable to withstand the load, and step-out that makes it impossible to synchronize the number of input pulses of the motor with the actual rotation of the motor There were problems such as the occurrence of

  As a method of preventing the belt member and the nip forming member from being worn by friction and preventing the above-described various problems, a lubricant is held between the inner peripheral surface of the belt member and the nip forming member. A configuration in which a low friction member having a low friction coefficient is provided is already known.

  For example, Patent Document 1 discloses a technology in which a lubricant holding member is provided between a fixing belt and a contact member, and the lubricant holding member and the inner peripheral surface of the fixing belt are in contact with each other at a nip portion. With this technique, the frictional force generated between the fixing belt and the contact member can be reduced, and the occurrence of the various problems described above can be prevented.

  However, in such a conventional fixing device, the lubricant holding member that holds the lubricant is in direct contact with the fixing belt. In such a case, if the lubricant held by the lubricant holding member is depleted over time, the frictional force between the lubricant holding member and the fixing belt increases, and the various problems described above occur. The problem of being left behind was left.

  The present invention has been made to solve the above-described problems, and provides a fixing device in which a lubricant that reduces a frictional force generated between a belt member and a nip portion forming member is not exhausted over time. For the purpose.

In order to achieve the above object, the fixing device according to the present invention includes a belt member having a heat source therein and bonded at both ends, a rotating body that rotates in contact with the belt member, and an inner peripheral surface side of the belt member. A nip portion forming member that forms a nip portion between the belt member and the rotating body by contacting the rotating body via the belt member; and an inner peripheral surface side of the belt member. By heating the lubricant supply member that holds the lubricant supplied to the surface portion of the nip portion forming member that is in contact with the rotating body via the belt member, and the recording medium conveyed to the nip portion. The fixing device is configured to fix an image on the recording medium, wherein the nip forming member has a flow path for supplying the lubricant supplied from the lubricant supplying member to the surface portion. And the flow path A plurality of hole portions for supplying the lubricant to the surface portion, and a plurality of the hole portions are provided at predetermined intervals in the longitudinal direction of the nip portion forming member, and the predetermined interval is The first predetermined interval on the outer side in the longitudinal direction of the nip portion forming member, and the second predetermined interval shorter than the first predetermined interval in the central portion in the longitudinal direction of the nip portion forming member. It has been characterized by Rukoto.

  According to the present invention, it is possible to provide a fixing device in which the lubricant that reduces the frictional force generated between the belt member and the nip portion forming member is not exhausted over time.

1 is a schematic perspective view of a tandem type color printer including a fixing device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of a fixing device according to an embodiment of the present invention. (A) is a schematic perspective view of the end of the fixing device according to the embodiment of the present invention, (b) is a schematic front view of the end of the fixing device, and (c) is a schematic cross section of the end of the fixing device. FIG. 1 is a schematic cross-sectional view of a fixing device according to an embodiment of the present invention. It is a schematic perspective view of the nip part formation member and lubricant supply member which concern on embodiment of this invention. It is a schematic sectional drawing which shows the state in which a lubricant is supplied from the lubricant supply member which concerns on embodiment of this invention. It is the schematic which shows the modification of the reflection member which concerns on embodiment of this invention. It is the schematic which shows the modification of the supporting member which concerns on embodiment of this invention. FIG. 9 is a schematic cross-sectional view showing a modification of the fixing device according to the embodiment of the present invention. It is a schematic sectional drawing which shows the modification of the lubricant supply member which concerns on embodiment of this invention. It is a schematic perspective view which shows the modification of the flow path which concerns on embodiment of this invention. It is a schematic front view which shows the modification of the flow path which concerns on embodiment of this invention. It is a schematic sectional drawing which shows the modification of the flow path which concerns on embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
1 to 6 are diagrams showing an embodiment of a fixing device and an image forming apparatus according to the present invention, and show an example in which the image forming apparatus is applied to a tandem type color printer.

  FIG. 1 is a diagram illustrating a configuration of an image forming apparatus. In FIG. 1, an image forming apparatus 1 includes image forming units 4Y, 4M, 4C, and 4K corresponding to respective colors (yellow (Y), magenta (M), cyan (C), and black (K)), and a sheet feeding unit. 12, a fixing device 20, an intermediate transfer unit 85, and a bottle container 101.

  The bottle storage unit 101 is provided above the image forming apparatus 1, and in the bottle storage unit 101, four toner bottles 102Y, 102M, 102C, and 102K corresponding to the respective colors are detachably installed.

  The intermediate transfer unit 85 is provided below the bottle storage unit 101, and includes an intermediate transfer belt 78, four primary transfer bias rollers 79Y, 79M, 79C, and 79K, an intermediate transfer cleaning unit 80, and a secondary transfer. And a backup roller 82. The intermediate transfer unit 85 includes a cleaning backup roller 83 and a tension roller 84.

  The image forming units 4Y, 4M, 4C, and 4K are provided side by side so as to face the intermediate transfer belt 78. The image forming units 4Y, 4M, 4C, and 4K are respectively photosensitive drums 5Y, 5M, 5C, and 5K, charging units 75Y, 75M, 75C, and 75K, developing units 76Y, 76M, 76C, and 76K, and a cleaning unit 77Y. , 77M, 77C, 77K, and a static elimination unit (not shown).

  The photosensitive drums 5Y, 5M, 5C, and 5K are rotationally driven in a clockwise direction in FIG. 1 by a drive motor (not shown). On the photosensitive drums 5Y, 5M, 5C, and 5K, an image forming process including a charging process, an exposure process, a developing process, a transfer process, and a cleaning process is executed.

  First, in the charging step, the photosensitive drums 5Y, 5M, 5C, and 5K are uniformly charged on the photosensitive drums 5Y, 5M, 5C, and 5K at the positions of the charging units 75Y, 75M, 75C, and 75K.

  Next, in the exposure process, the photosensitive drums 5Y, 5M, 5C, and 5K are irradiated with the laser beams Ly, Lm, Lc, and Lk emitted from the exposure unit 3, and exposed to the photosensitive drums 5Y, 5M, 5C, and so on. An electrostatic latent image corresponding to each color is formed on 5K.

  Next, in the developing process, the photosensitive drums 5Y, 5M, 5C, and 5K are arranged so that the electrostatic latent images on the photosensitive drums 5Y, 5M, 5C, and 5K are at positions facing the developing devices 76Y, 76M, 76C, and 76K. Developed. As a result, toner images of respective colors are formed on the photosensitive drums 5Y, 5M, 5C, and 5K.

  Next, in the primary transfer step, the photosensitive drums 5Y, 5M, 5C, and 5K are positioned at positions facing the intermediate transfer belt 78 and the first transfer bias rollers 79Y, 79M, 79C, and 79K, and the photosensitive drums 5Y, 5M, The toner images on 5C and 5K are transferred onto the intermediate transfer belt 78. At this time, a small amount of untransferred toner remains on the photosensitive drums 5Y, 5M, 5C, and 5K.

  Next, in the cleaning process, the photosensitive drums 5Y, 5M, 5C, and 5K are untransferred toner remaining on the photosensitive drums 5Y, 5M, 5C, and 5K at positions facing the cleaning units 77Y, 77M, 77C, and 77K. Is mechanically collected by the cleaning blades of the cleaning units 77Y, 77M, 77C, and 77K.

  Then, the residual potentials on the photosensitive drums 5Y, 5M, 5C, and 5K are removed from the photosensitive drums 5Y, 5M, 5C, and 5K at positions facing the neutralization unit.

  Through the above image forming process, a toner image of each color is formed on the intermediate transfer belt 78.

  The intermediate transfer belt 78 is supported in a tensioned state by a secondary transfer backup roller 82, a cleaning backup roller 83, and a tension roller 84.

  The four primary transfer bias rollers 79Y, 79M, 79C, and 79K sandwich the intermediate transfer belt 78 with the photosensitive drums 5Y, 5M, 5C, and 5K, respectively, thereby forming primary transfer nips. Further, a transfer bias reverse to the polarity of the toner is applied to the primary transfer bias rollers 79Y, 79M, 79C, and 79K.

  The intermediate transfer belt 78 is moved in the direction of the arrow in FIG. 1 by the rotational drive of the secondary transfer backup roller 82, and sequentially passes through the primary transfer nips of the primary transfer bias rollers 79Y, 79M, 79C, and 79K.

  As a result, the toner images of the respective colors on the photosensitive drums 5Y, 5M, 5C, and 5K are primarily transferred while being superimposed on the intermediate transfer belt 78. Thereafter, the intermediate transfer belt 78 onto which the toner images of the respective colors are transferred in an overlapping manner reaches a position facing the secondary transfer roller 89.

  The four-color toner images formed on the intermediate transfer belt 78 are conveyed to the position of the secondary transfer nip formed by sandwiching the intermediate transfer belt 78 between the secondary transfer backup roller 82 and the secondary transfer roller 89. Is transferred onto the recorded recording medium P.

  Then, the intermediate transfer belt 78 reaches the position of the intermediate transfer cleaning unit 80, and untransferred toner that has not been transferred to the recording medium P remaining on the intermediate transfer belt 78 is collected.

  The paper feeding unit 12 is provided below the image forming apparatus 1, and a plurality of recording media P such as transfer paper are stored in the paper feeding unit 12 in a stacked manner.

  The recording medium P is composed of plain paper, but in addition to plain paper, it is thick paper, postcard, envelope, thin paper, coated paper (coated paper, art paper, etc.), tracing paper, OHP sheet, etc. May be.

  Next, a process for conveying the recording medium P from the paper supply unit 12 will be described.

  First, the uppermost recording medium P stored in the paper supply unit 12 is directed between the registration rollers 98a and 98b by the paper supply roller 97 being rotated counterclockwise in FIG. Are transported.

  Next, the recording medium P temporarily stops at the position of the roller nip provided between the registration rollers 98a and 98b.

  The recording medium P is conveyed toward the secondary transfer nip when the registration rollers 98a and 98b are rotationally driven in accordance with the timing when the toner image on the intermediate transfer belt 78 comes. As a result, the toner image is transferred onto the recording medium P.

  The recording medium P on which the toner image is transferred at the position of the secondary transfer nip is conveyed to the position of the fixing device 20. The toner image transferred onto the recording medium P is fixed on the recording medium P by heat and pressure by the fixing belt 21 serving as a belt member and the pressure roller 22 serving as a rotating body, whereby a color image is recorded on the recording medium P. Fix to P.

The recording medium P on which the color image is fixed is discharged out of the image forming apparatus 1 through the paper discharge rollers 99a and 99b, and is stacked on the stack unit 100 as an output image.
Thus, a series of image forming processes in the image forming apparatus 1 is completed.

FIG. 2 is a diagram illustrating the configuration of the fixing device 20.
As shown in FIG. 2, the fixing device 20 includes a fixing belt 21, a pressure roller 22, a heater 23 as a heat source, a nip forming member 24, a stay 25 as a support member, a reflecting member 26, A temperature sensor 27 and a separation member 28 are provided. The fixing device 20 includes a low friction sheet 29 as a low friction member and a lubricant supply member 30.

  The fixing belt 21 is a thin and flexible endless belt, and rotates in the direction of the arrow in FIG. Here, the endless shape means a state in which both ends of the belt are joined and no joint exists.

  The fixing belt 21 has a thin and small-diameter laminated structure in order to reduce the heat capacity, and a base material layer and a release layer are sequentially laminated from the inner peripheral surface side, and the total thickness is The diameter is set to 1 mm or less, and the diameter is set to 20 to 40 mm. This is an exemplification, and the present invention is not limited to this.

  The base material layer of the fixing belt 21 has a layer thickness of 20 to 50 μm and is formed of a metal material such as nickel or SUS or a resin material such as polyimide (PI). This is an exemplification, and the present invention is not limited to this.

  The release layer of the fixing belt 21 has a layer thickness of 10 to 50 μm, and is formed of a material such as PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) or PTFE (polytetrafluoroethylene). By providing the release layer, the fixing belt 21 is secured with respect to the toner image T on the recording medium P. This is an exemplification, and the present invention is not limited to this. Moreover, the mold release means that the bonded objects are peeled off, and the mold release property means the ease of peeling between the objects.

  The heater 23 is composed of a halogen heater, and both ends thereof are fixed to side plates (not shown) of the fixing device 20 and are configured to generate heat when output is controlled by a power supply unit provided in the printer body. ing. The output control of the heater 23 is performed based on the result of detecting the surface temperature of the fixing belt 21 by the temperature sensor 27 facing the surface of the fixing belt 21.

  Further, the fixing device 20 can set the fixing temperature of the fixing belt 21 for fixing the color image on the recording medium P to a desired temperature by such output control of the heater 23. Here, the temperature sensor 27 is configured by a thermistor or the like.

  The heater 23 is opposed to the fixing belt 21 and a reflection member 26 described later, and is configured to directly heat the fixing belt 21 at a place other than the nip portion N by generating radiant heat.

  Thereby, since the heating efficiency of the fixing belt 21 by the heater 23 is improved, the fixing device 20 is excellent in energy saving and can shorten the first print time. The first print time means the time required to print the first sheet on a recording medium after receiving a print start instruction and to discharge the recording medium to the outside of the image forming apparatus.

  The nip portion forming member 24 is made of polyethersulfone (PES), polyphenylene sulfide (PPS), liquid crystal polymer (LCP), polyethernitrile (PEN), polyamideimide (PAI) which is a heat resistant member having a heat resistant temperature of 200 ° C. or higher. It is made of a heat resistant resin material such as polyetheretherketone (PEEK). This is an exemplification, and the present invention is not limited to this.

  Since the nip portion forming member 24 is made of a heat resistant resin material, the fixing device 20 prevents the nip portion forming member 24 from being deformed by heat in the toner fixing temperature region, and ensures a stable state of the nip portion N. The output image quality can be stabilized.

  The nip portion forming member 24 is provided such that the axial direction of the fixing belt 21 is the longitudinal direction, and the contact portion protrudes from the base portion 24a in the thickness direction of the recording medium P (hereinafter simply referred to as “thickness direction”). 24 b comes into contact with the stay 25 and is fixedly supported by the stay 25.

  By fixing and supporting the nip portion forming member 24 on the stay 25, the fixing device 20 can prevent the nip portion forming member 24 from being bent by the pressure of the pressure roller 22, and a uniform nip in the longitudinal direction. The width can be obtained.

  The nip portion forming member 24 is formed smaller than the stay 25 in order to ensure the mechanical strength of the stay 25. Detailed structures of the nip portion forming member 24 and the stay 25 will be described later.

  Further, the nip portion forming member 24 is in contact with the inner peripheral surface of the fixing belt 21 through the low friction sheet 29 having a small surface friction coefficient at the nip portion N. By providing the low friction sheet 29, the fixing device 20 reduces the frictional force generated between the nip portion forming member 24 and the fixing belt 21, thereby reducing the driving torque generated when the fixing belt 21 rotates. The

  As a result, the nip portion forming member 24 is prevented from being worn by frictional force generated between the nip portion forming member 24 and the fixing belt 21.

  The nip portion forming member 24 is provided with a lubricant supply member 30 described later in a space 24 c that faces the stay 25 and does not contact the stay 25. The detailed structure of the nip portion forming member 24 and the lubricant supply member 30 will be described later.

  The stay 25 reinforces and supports the nip portion forming member 24 that forms the nip portion N, and is fixed and positioned on a belt holding member 40 described later. The stay 25 comes into contact with the pressure roller 22 via the nip portion forming member 24, the low friction sheet 29 and the fixing belt 21, so that the nip portion forming member 24 receives the pressing force of the pressure roller 22 at the nip portion N. Therefore, the occurrence of defects that cause large deformations is suppressed.

  The stay 25 is preferably formed of a metal material having high mechanical strength such as stainless steel or iron alloy in order to satisfy the above-described function, but may be formed of a resin material. The detailed structure of the stay 25 will be described later.

  The reflection member 26 is fixed between the stay 25 and provided between the stay 25 and the heater 23. The reflecting member 26 is formed in a concentric shape centering on the heater 23 that reflects the radiant heat and radiant light (hereinafter simply referred to as “radiant heat”) emitted from the heater 23 toward the reflecting member 26 toward the fixing belt 21. The reflecting surface 26a is provided. Further, since the reflecting member 26 is directly heated by the heater 23, the reflecting member 26 is formed of a metal material having a high melting point.

  The reflection surface 26a of the reflection member 26 has a reflectance set to 90% or more. In addition, this is an illustration and this invention is not limited to this.

  By providing the reflection member 26, the fixing device 20 can increase the radiant heat applied to the fixing belt 21, and can efficiently heat the fixing belt 21. Further, since the fixing device 20 can suppress transmission of radiant heat from the heater 23 to the stay 25 and the like, energy saving can be achieved.

  The separation member 28 is fixed to the fixing device 20 and separates the recording medium P from the surface of the fixing belt 21 by contacting the recording medium P on which the color image is fixed at the nip portion N.

  The pressure roller 22 is a roller having a diameter of about 20 to 40 mm provided so as to be in contact with the outer peripheral surface of the fixing belt 21 at the position of the nip portion N, and an elastic layer on the heat-resistant solid core metal 22a. 22b is formed, and a thin release layer 22c is formed on the surface of the elastic layer 22b. This is an exemplification, and the present invention is not limited to this.

  The pressure roller 22 is pressed against the fixing belt 21, the low friction sheet 29 and the nip portion forming member 24 by a pressure mechanism (not shown), whereby the elastic layer 22 b is crushed. As a result, the fixing device 20 forms a desired nip portion N where the recording medium P is conveyed between the pressure roller 22 and the fixing belt 21.

  The pressure roller 22 is rotationally driven in the direction of the arrow in FIG. 2 by a drive mechanism such as a motor (not shown) provided in the image forming apparatus main body, and transmits a driving force to the fixing belt 21 at the nip portion N. 21 is driven to rotate.

  The elastic layer 22b of the pressure roller 22 is formed of a material such as foamable silicone rubber, silicone rubber, or fluororubber, and has a thickness set to 100 μm or more. Further, the release layer 22c of the pressure roller 22 is formed of a material such as PFA or PTFE. This is an exemplification, and the present invention is not limited to this.

  Since the elastic layer 22b has a thickness of 100 μm or more, the fixing device 20 absorbs minute irregularities on the surface of the fixing belt 21 due to elastic deformation of the elastic layer 22b and fixes the color image on the recording medium P. Generation of a skin image can be prevented. Here, the cocoon skin image means an image in which a number of minute irregularities are formed on the surface.

Next, a normal operation of the fixing device 20 configured as described above will be briefly described.
When the power switch of the image forming apparatus 1 is turned on, electric power is supplied to the heater 23 and rotation driving of the pressure roller 22 in the direction of the arrow in FIG.

  Accordingly, the fixing belt 21 is driven to rotate in the direction of the arrow in FIG. Thereafter, the recording medium P is fed from the paper feeding unit 12, and the unfixed toner image T is transferred onto the recording medium P at the position of the secondary transfer roller 89.

  The recording medium P to which the unfixed toner image T has been transferred is conveyed in the direction of arrow A1 in FIG. 2 while being guided by a guide plate (not shown), and is pressed between the fixing belt 21 and the pressure roller 22 in a pressed state. It is carried into the nip part.

  The color image on the surface of the recording medium P is recorded by the heating by the fixing belt 21 heated by the heater 23 and the pressing force by the nip forming member 24 reinforced by the stay 25 and the pressure roller 22. It is fixed on the medium P.

  The recording medium P on which the color image is fixed is conveyed from the nip portion N in the direction of the arrow A2, and is separated from the fixing belt 21 by the leading end of the recording medium P coming into contact with the leading end of the separation member 28. Thereafter, the separated recording medium P is discharged out of the image forming apparatus 1 by the discharge rollers 99a and 99b, and is stacked on the stack unit 100 as an output image.

  3A to 3C are diagrams illustrating the configuration of the end portion of the fixing belt 21 of the fixing device 20. 3A to 3C, only the configuration of one end is illustrated, but the single end also has the same configuration.

  As shown in FIGS. 3A and 3B, the fixing device 20 includes a belt holding member 40 at an end portion of the fixing belt 21, a snap ring 41 as a protective member that protects the end portion of the fixing belt 21, and And a shielding member (not shown).

  As shown in FIG. 3C, the belt holding member 40 is formed in a substantially cylindrical shape having an open position of the nip portion N to which the nip portion forming member 24 is attached, and the end portion of the fixing belt 21 can be rotated. Hold on.

  As shown in FIGS. 3A and 3B, the snap ring 41 is provided between the end surface of the fixing belt 21 and the opposing surface of the belt holding member 40 that opposes the fixing belt 21. And fitted in the fixing device 20 with a margin.

  The snap ring 41 is made of a so-called super engineer plastic such as PEEK, PPS, PAI, etc., which has excellent heat resistance. In addition, this is an illustration and this invention is not limited to this.

  The snap ring 41 prevents the end portion of the fixing belt 21 and the belt holding member from coming into direct contact when the fixing belt 21 is displaced in the axial direction, thereby preventing wear and deterioration of the end portion of the fixing belt 21. To prevent.

  Further, since the snap ring 41 is fitted in the fixing device 20 with a margin with respect to the outer periphery of the belt holding member 40, the snap ring 41 rotates together with the fixing belt 21 when the end portion of the fixing belt 21 comes into contact. It is possible.

  The shielding member is provided between the fixing belt 21 and the heater 23 and shields radiant heat from the heater 23. As a result, when the recording medium P is continuously conveyed, the fixing device 20 can suppress an excessive temperature rise in the non-passing area where the recording medium P of the fixing belt 21 does not pass. Deterioration due to heat can be prevented.

FIG. 4 is a diagram illustrating the configuration of the nip portion forming member 24 and the stay 25.
As shown in FIG. 4, the stay 25 includes a base portion 25a and a protruding portion 25b.

  The base 25 a is formed so that the width in the transport direction of the recording medium P (hereinafter simply referred to as “transport direction”) is larger than the width in the transport direction of the nip portion forming member 24, and the contact portion of the nip portion forming member 24. 24b is in contact.

  When the base portion 25a and the contact portion 24b come into contact with each other, the nip forming member 24 is deformed by the pressure applied by the pressure roller 22 when the pressure applied by the pressure roller 22 is received at the nip portion N. Is deterred.

  The protrusions 25 b are provided at the upstream and downstream ends of the base 25 a in the transport direction, protrude in the thickness direction from the ends of the base 25 a, and the tip of the protrusion 25 b is the inner circumference of the fixing belt 21. Close to the surface.

  Further, a reflection member 26 is provided on the protruding portion 25b on the upstream side in the transport direction. Therefore, the end portion of each protrusion 25 b is protected from the radiant heat generated from the heater 23 by the reflecting member 26.

  The projecting amount of the projecting portion 25b is such that the distance d in the thickness direction between the reflecting member 26 covering the tip of the projecting portion 25b and the inner peripheral surface of the fixing belt 21 is within a predetermined value range. Is set not to touch.

  By forming the stay 25 so that the tip of the protrusion 25b is close to the inner peripheral surface of the fixing belt 21, the protrusion 25b can be provided long in the thickness direction. Thereby, since the stay 25 has a laterally long cross-sectional area in which the protruding portion 25b extends in the thickness direction, the cross-section coefficient increases, and the mechanical strength can be improved.

  Here, the nip portion forming member 24 has a thickness direction height h1 of an end portion on the upstream side in the transport direction of the base portion 24a and a thickness direction height h2 of the end portion on the downstream side in the transport direction of the base portion 24a. 24a and the contact portion 24b are configured to have a height h3 or less, which is the sum of the heights in the thickness direction.

  With such a configuration of the base portion 24 a of the nip portion forming member 24, the fixing device 20 has a nip between the upstream and downstream ends of the base portion 25 a of the stay 25 and the inner peripheral surface of the fixing belt 21. The portion forming member 24 is not interposed.

  Accordingly, the fixing device 20 can provide the large stay 25 in a limited space in the fixing belt 21, and the mechanical strength of the stay 25 can be improved.

  Further, the fixing belt 21 is configured such that an end portion thereof is guided by the nip portion forming member 24 and the belt holding member 40 and a portion other than the end portion is guided by the nip portion forming member 24.

  That is, since the fixing device 20 is not provided with a guide member other than the nip portion forming member 24 between the fixing belt 21 and the stay 25, the stay 25 having a size that can approach the fixing belt 21 can be provided. The mechanical strength of 25 can be improved.

  In addition, the fixing device 20 is provided with a heater 23 on the inner side of the two protruding portions 25b of the stay 25 or on the inner side of the extension line L of the inner surfaces of the two protruding portions 25b. Accordingly, the fixing device 20 can accommodate the heater 23 and the stay 25 in the fixing belt 21 in a compact manner.

  Here, in general, in a fixing device that directly heats a belt member with a heat source, the temperature of the belt member tends to increase in a portion near the heat source, while the temperature of the belt member tends to decrease in a portion far from the heat source. Such a fixing device has a problem that the temperature of the belt member rapidly increases locally and the belt member deteriorates.

  In the fixing device 20 according to the present embodiment, the heater 23 is housed inside the stay 25, and the irradiation range of the radiant heat to the fixing belt 21 is narrowed to a range with relatively little variation in distance, thereby causing variations in heating temperature. Is suppressed. As a result, the fixing device 20 can prevent the temperature of the fixing belt 21 from rising locally and improve the image quality.

  As described above, the fixing device 20 can improve the mechanical strength of the stay 25 by forming the tip of the protruding portion 25 b of the stay 25 so as to be close to the inner peripheral surface of the fixing belt 21. As a result, the fixing device 20 can prevent the nip portion forming member 24 from being bent and greatly deformed by the pressure applied by the pressure roller 22.

  Further, since the deformation due to the bending of the nip portion forming member 24 is suppressed, the fixing device 20 can uniformly form the nip portion N over the longitudinal direction of the nip portion forming member 24, which is favorable. Can be obtained.

  In the configuration in which the diameter of the fixing belt 21 is reduced, the space for providing the stay 25 is also reduced. However, by applying the above configuration, the protruding portion 25b can be provided longer in the thickness direction, and the Strength can be improved.

  Further, since the fixing device 20 is configured such that the nip portion forming member 24 is formed small and no separate guide member is provided between the fixing belt 21 and the stay 25, a space for providing the stay 25 in the fixing belt 21 is increased. Can be secured.

  As a result, the fixing device 20 can form the stay 25 in a sufficiently large size, and more reliably prevent the nip portion forming member 24 from being bent and greatly deformed by the pressure applied by the pressure roller 22. Can do.

FIGS. 5 and 6 are diagrams illustrating the configuration of the nip portion forming member 24, the low friction sheet 29, and the lubricant supply member 30.
As shown in FIGS. 5 and 6, the nip forming member 24 includes a base 24a, a contact 24b, a space 24c, a surface 24d, a flow path 24e, a hole 24f, and a groove 24g. Has been.

  The base portion 24a is provided in the longitudinal direction, has a contact portion 24b on the surface facing the stay 25, has a surface portion 24d on the surface facing the nip portion N, and has a flow path 24e inside. doing.

  The contact portion 24b is provided in the vicinity of each end portion on the upstream side and the downstream side in the transport direction of the base portion 24a, and protrudes from the base portion 24a in the thickness direction. The nip portion forming member 24 is configured such that deformation due to the pressure of the pressure roller 22 is suppressed when the contact portion 24 b contacts the base portion 25 a of the stay 25.

  The space 24c is formed between the two contact portions 24b and the base portion 24a provided in the vicinity of the upstream and downstream ends of the base portion 24a in the transport direction, and the lubricant supply member 30 is accommodated therein. Has been.

  The surface portion 24 d is provided on the surface of the base portion 24 a that forms the nip portion N by contacting the pressure roller 22 via the fixing belt 21 and the low friction sheet 29, and contacts the low friction sheet 29. The pressure applied by the pressure roller 22 is received. A plurality of grooves 24g are formed on the surface portion 24d.

  The flow path 24e is provided inside the base 24a, and has a plurality of holes 24f and a plurality of grooves 24g. The nip portion forming member 24 supplies the lubricant supplied from the lubricant supply member 30 to the surface portion 24d through the flow path 24e.

  The plurality of hole portions 24f are provided in the groove portion 24g over the longitudinal direction of the nip portion forming member 24, and are formed so that the intervals in the longitudinal direction between the hole portions 24f are equal. Further, the diameter of the hole 24f is formed such that the lubricant held in the lubricant supply member 30 can pass through the hole 24f by capillary action. In addition, in FIG. 6, although the hole part 24f is provided in 22 places, the number of the hole parts 24f is not limited to this.

  Since the plurality of hole portions 24f are provided in the longitudinal direction of the nip portion forming member 24, the nip portion forming member 24 is supplied from the lubricant supply member 30 in the longitudinal direction of the surface portion 24d. Can be supplied.

  The plurality of groove portions 24g are provided on the surface portion 24d in the longitudinal direction of the base portion 24a, and are configured so that the lubricant supplied from the lubricant supply member 30 is filled in the groove portions 24g through the hole portions 24f. ing. In addition, in FIG. 6, although the groove part 24g is provided in two places, the number of the groove parts 24g is not limited to this.

  Since the plurality of groove portions 24g are provided in the longitudinal direction of the nip portion forming member 24, the nip portion forming member 24 receives the lubricant supplied from the lubricant supply member 30 in the longitudinal direction of the surface portion 24d. Can be supplied.

  The low friction sheet 29 is provided between the surface portion 24d and the fixing belt 21, and is formed of a material having a small friction coefficient. Further, the low friction sheet 29 holds the lubricant supplied from the lubricant supply member 30, thereby reducing the frictional force generated between the fixing belt 21 and the nip portion forming member 24.

  Accordingly, the fixing device 20 can prevent the fixing belt 21 and the nip portion forming member 24 from being deteriorated and worn by the frictional force generated between the fixing belt 21 and the nip portion forming member 24 in the nip portion N. .

  The lubricant supply member 30 holds the lubricant therein, and is provided in the space 24 c over the longitudinal direction of the nip portion forming member 24. The lubricant supply member 30 is made of a sponge-like elastic material capable of storing a large amount of lubricant such as a silicon sponge material or a fluorine-based sponge material.

  The lubricant supply member 30 supplies the lubricant held inside to the groove 24g through the hole 24f by capillary action, and fills the groove 24g with the lubricant. By filling the groove portion 24g with the lubricant, the nip portion forming member 24 can supply the lubricant to the surface portion 24d.

  Therefore, when the lubricant on the surface that contacts the inner peripheral surface of the fixing belt 21 of the low-friction sheet 29 decreases due to contact with the fixing belt 21, the fixing device 20 causes a flow path from the lubricant supply member 30 due to capillary action. Lubricant is supplied to the low friction sheet 29 through 24e.

  As a result, the fixing device 20 can constantly supply the lubricant to the low friction sheet 29 in contact with the surface portion 24d, and always suppresses the friction coefficient of the surface of the low friction sheet 29 without being exhausted over time. can do.

  Further, when the lubricant held in the lubricant supply member 30 is depleted, the fixing device 20 can be reused by supplying the lubricant to the lubricant supply member 30 depleted of the lubricant. There is no need to perform the operation, and it is possible to reduce the cost for parts replacement.

  As described above, the fixing device 20 according to the present embodiment includes the fixing belt 21 having the heater 23 therein and bonded at both ends, and the pressure roller 22 that rotates in contact with the fixing belt 21.

  The fixing device 20 is provided on the inner peripheral surface side of the fixing belt 21, and forms a nip portion N between the fixing belt 21 and the pressure roller 22 by contacting the pressure roller 22 via the fixing belt 21. The nip portion forming member 24 is provided.

  The fixing device 20 is provided on the inner peripheral surface side of the fixing belt 21 and holds the lubricant supplied to the surface portion 24 d that contacts the pressure roller 22 via the fixing belt 21 of the nip portion forming member 24. A lubricant supply member 30 is provided. The fixing device 20 fixes the image on the recording medium P by heating the recording medium P conveyed to the nip portion N.

  The nip portion forming member 24 has a flow path 24e for supplying the lubricant supplied from the lubricant supply member 30 to the surface portion 24d.

  For this reason, the fixing device 20 can continuously supply the lubricant to the surface portion 24d, and the lubricant is not exhausted over time, and the inner peripheral surface of the fixing belt 21 and the nip portion forming member 24 are always The frictional force generated during the period can be reduced.

  Further, when the lubricant held in the lubricant supply member 30 is depleted, the fixing device 20 can be reused by supplying the lubricant to the lubricant supply member 30 depleted of the lubricant. There is no need to perform the operation, and it is possible to reduce the cost for parts replacement.

  The flow path 24e of the fixing device 20 according to the present embodiment has a plurality of holes 24f for supplying the lubricant to the surface portion 24d.

  For this reason, in the fixing device 20, the plurality of hole portions 24 f are provided over the longitudinal direction of the nip portion forming member 24, and therefore, the lubricant supply member extends over the longitudinal direction of the surface portion 24 d of the nip portion forming member 24. The lubricant supplied from 30 can be supplied.

  Further, the flow path 24e of the fixing device 20 according to the present embodiment has a plurality of groove portions 24g for supplying the lubricant to the surface portion 24d.

  For this reason, in the fixing device 20, since the plurality of groove portions 24 g are provided in the longitudinal direction of the nip portion forming member 24, the lubricant supply member 30 extends in the longitudinal direction of the surface portion 24 d of the nip portion forming member 24. Lubricant supplied from can be supplied.

  The fixing device 20 according to the present embodiment includes a stay 25 that is provided on the inner peripheral surface side of the fixing belt 21 and that supports the nip portion forming member 24 by contacting the nip portion forming member 24. The fixing device 20 includes a low friction sheet 29 that is provided on the inner peripheral surface side of the fixing belt 21 and reduces frictional resistance generated between the fixing belt 21 and the nip portion forming member 24. The low friction sheet 29 holds the lubricant supplied from the lubricant supply member 30.

  For this reason, the fixing device 20 prevents the stay 25 and the nip portion forming member 24 from contacting each other, thereby causing the nip portion forming member 24 to be bent and greatly deformed due to the pressing force of the pressure roller 22 in the nip portion N. can do.

  In the fixing device 20, the low friction sheet 29 having a small surface friction coefficient comes into contact with the fixing belt 21 and the nip portion forming member 24 at the nip portion N. Accordingly, the fixing device 20 can prevent the fixing belt 21 and the nip portion forming member 24 from being deteriorated and worn by the frictional force generated between the inner peripheral surface of the fixing belt 21 and the nip portion forming member 24. .

  In the present embodiment, the fixing belt 21 includes a base material and a release layer. However, the fixing belt 21 is not limited thereto, and for example, an elastic layer may be provided between the base material and the release layer. The elastic layer has a layer thickness of 100 to 300 μm and may be formed of a rubber material such as silicone rubber, foamable silicone rubber, or fluororubber. In addition, this is an illustration and this invention is not limited to this.

  By providing the elastic layer, the fixing device 20 allows the surface of the fixing belt 21 to be minute when fixing a color image on the recording medium P at the nip formed between the fixing belt 21 and the pressure roller 22. Unevenness is not formed, and heat is uniformly transmitted to the toner image T on the recording medium P. As a result, the fixing device 20 can suppress the occurrence of a cocoon skin image on the recording medium P.

  In the present embodiment, the entire thickness of the fixing belt 21 is set to 1 mm or less, but is preferably 0.2 mm or less, and more preferably 0.16 mm or less. .

  In the present embodiment, the fixing belt 21 is set to have a diameter of 20 to 40 mm, but is preferably 30 mm or less.

  In the present embodiment, the heater 23 is configured by a halogen heater, but is not limited thereto, and may be configured by, for example, an induction heating type heater, a resistance heating element, or a carbon heater.

  In the present embodiment, the fixing device 20 is provided with the reflecting member 26. However, the present invention is not limited to this. For example, the surface of the stay 25 facing the heater 23 is subjected to a mirror surface treatment such as polishing or painting, and reflected. A reflective surface with a rate of 90% or more may be formed. In addition, this is an illustration and this invention is not limited to this.

  However, since the shape and material of the stay 25 cannot be freely selected in order to ensure the strength, if the reflecting member 26 is separately provided as in the present embodiment, the degree of freedom in selecting the shape and material is increased, and the reflection is reduced. Both the member 26 and the stay 25 can be specialized for their respective functions.

  When the reflecting member 26 is provided between the stay 25 and the heater 23, the fixing device 20 is provided with the reflecting member 26 that reflects the radiant heat of the heater 23 closer to the stay 25. Accordingly, the fixing device 20 can heat the fixing belt 21 more efficiently than the case where the reflecting member 26 is not provided. Therefore, it is desirable to provide the reflecting member 26.

  In the present embodiment, the reflection surface 26 a of the reflection member 26 is formed in a concentric shape with the heater 23 a as the center. However, the present invention is not limited to this, and for example, a part or all of the reflection surface 26 a is other than the heater 23. In this direction, the radiant heat may be reflected to the fixing belt 21 side.

  Here, as shown in FIG. 7A, when the reflection surface 26 a is formed concentrically with the heater 23 a as the center, the radiant heat emitted from the heater 23 is reflected toward the heater 23.

  On the other hand, as shown in FIG. 7B, a part or all of the reflecting surface 26 a is formed in a direction to reflect the radiant heat toward the fixing belt 21 in the direction other than the heater 23, thereby moving toward the heater 23. The reflected radiant heat can be reduced. Thereby, the fixing device 20 can further improve the heating efficiency of the fixing belt 21 by the reflection of the radiant heat of the reflecting surface 26a.

  In the present embodiment, the cored bar 22a of the pressure roller 22 has a solid structure, but is not limited thereto, and may have a hollow structure. In this case, the pressure roller 22 may have a configuration having a heating source such as a halogen heater inside the cored bar 22a.

  In the present embodiment, the pressure roller 22 includes the elastic layer 22b. However, the configuration is not limited thereto, and the pressure roller 22 may be configured not to include the elastic layer 22b. In this case, since the heat capacity of the pressure roller 22 is reduced, the fixing device 20 is improved in fixing performance for fixing a color image on the recording medium P.

  However, since the pressure roller 22 does not have the elastic layer 22b, when the fixing device 20 fixes the color image on the recording medium P, the minute unevenness on the surface of the fixing belt 21 is transferred to the image, and the cocoon skin An image may occur. In order to prevent this, the fixing device 20 is desirably provided with an elastic layer 22b.

  Further, when the elastic layer 22b is formed of a sponge-like material such as foamable silicone rubber, the applied pressure acting on the nip portion N can be reduced, so that the bending generated in the nip portion forming member 24 is reduced. be able to. In this case, the heating efficiency of the fixing belt 21 is improved because the heat of the fixing belt 21 becomes difficult to move to the pressure roller 22 side.

  In the present embodiment, the fixing device 20 is configured to press the fixing belt 21 by the pressure roller 22, but the invention is not limited thereto, and the pressure roller 22 contacts the fixing belt 21 without pressing it. It may be configured to do only.

  In the present embodiment, the diameter of the fixing belt 21 is formed to be equal to the diameter of the pressure roller 22, but the present invention is not limited thereto, and the diameter of the fixing belt 21 is larger than the diameter of the pressure roller 22. You may form so that it may become small.

  In this case, since the curvature of the fixing belt 21 at the nip portion N is smaller than the curvature of the pressure roller 22, the recording medium P fed from the nip portion N is easily separated from the fixing belt 21.

  Further, in the present embodiment, the snap ring 41 is configured to be rotatable together with the fixing belt 21 when the end portion of the fixing belt 21 comes into contact, but not limited thereto, the end portion of the fixing belt 21 is not limited to this. You may be comprised so that it may stop when it contacts.

  In the present embodiment, the stay 25 is provided so that the protruding portion 25b is substantially orthogonal to the base portion 25a. However, the present invention is not limited to this, and as shown in FIG. May be inclined with respect to the base portion 25a. Moreover, as shown in FIG.8 (b), the protrusion part 25b may be one.

  Regardless of the shape of the protruding portion 25b, the stay 25 increases the protruding amount of the protruding portion 25b by forming the tip of the protruding portion 25b close to the inner peripheral surface of the fixing belt 21. The strength of the stay 25 can be improved. Further, the shape of the stay 25 can be formed in other shapes.

  In the present embodiment, one heater 23 is provided in the fixing belt 21, but the present invention is not limited to this, and a plurality of heaters 23 may be provided. An example in which three heaters 23 are provided will be described below, but the number of heaters 23 is not limited to this.

  As shown in FIG. 9, the fixing device 20 includes three heaters 23a, 23b, and 23c. By providing the heaters 23a, 23b, and 23c, the fixing device 20 can vary the heat generation area for each heater, and can heat the fixing belt 21 in a range corresponding to the width of the recording medium P having various widths. it can.

  Even when three heaters 23 are provided, the protruding portion 25 b of the stay 25 is formed so that the tip is close to the inner peripheral surface of the fixing belt 21. In FIG. 7, the height dimensions h1, h2, and h3 of the nip portion forming member 24 are the same as h1, h2, and h3 shown in FIG. 5, and h1 and h2 are equal to or less than h3. Is set.

  In the present embodiment, the lubricant supply member 30 is formed of a sponge-like elastic member, but is not limited thereto, and may be a cloth material such as a nonwoven fabric or a woven fabric. Further, the lubricant supply member 30 may have an oil tank shape that can store the lubricant directly.

  Further, in the present embodiment, the lubricant supply member 30 is provided in the space 24c of the nip portion forming member 24. However, the present invention is not limited to this. For example, as shown in FIG. It may be provided on the side surface portion 24h on the upstream side in the transport direction of 24a.

  In this case, as shown in FIG. 10, the flow path 24e of the nip forming member 24 has a plurality of holes 24f, a plurality of grooves 24g, and a side surface 24h provided from the upstream side toward the downstream side in the transport direction. And a non-through hole 24i.

  In the present embodiment, the hole portions 24f are provided with a plurality of intervals in the longitudinal direction of each hole portion 24f. However, the present invention is not limited to this, and the intervals may not be equal. For example, as shown in FIG. 11, the interval between the hole portions 24f is a first predetermined interval L1 on the outer side in the longitudinal direction of the nip portion forming member 24 and a first central portion in the longitudinal direction of the nip portion forming member 24. You may be comprised by the 2nd predetermined space | interval L2 shorter than the predetermined space | interval L1.

  Accordingly, the fixing device 20 can supply more lubricant to the central portion in the longitudinal direction than to the outside in the longitudinal direction of the nip portion forming member 24. Therefore, the fixing device 20 can further reduce the frictional force in the central portion in the longitudinal direction where the frictional force generated between the inner peripheral surface of the fixing belt 21 and the nip portion forming member 24 increases.

  Further, the fixing device 20 supplies more lubricant to the central portion in the longitudinal direction than to the outside in the longitudinal direction of the nip portion forming member 24, so that the lubricant leaks out of the nip portion forming member 24 from the outside in the longitudinal direction. Can be prevented.

  Moreover, in this Embodiment, although the hole part 24f is formed in the diameter with the same diameter of each hole part 24f, not only this but a diameter from which each differs may be sufficient. For example, as shown in FIG. 12, the hole portion 24 f has a diameter of the hole portion 24 f provided in the center portion in the longitudinal direction of the nip portion forming member 24, and the hole portion 24 f is provided outside in the longitudinal direction of the nip portion forming member 24. It may be formed larger than the diameter of the portion 24f.

  Accordingly, the fixing device 20 can supply more lubricant to the central portion in the longitudinal direction than to the outside in the longitudinal direction of the nip portion forming member 24. Therefore, the fixing device 20 can further reduce the frictional force in the central portion in the longitudinal direction where the frictional force generated between the inner peripheral surface of the fixing belt 21 and the nip portion forming member 24 increases.

  Further, since the fixing device 20 supplies more lubricant to the central portion in the longitudinal direction than to the outside in the longitudinal direction of the nip portion forming member 24, the lubricant leaks out of the nip portion forming member 24 from the outside in the longitudinal direction. Can be prevented.

  In the present embodiment, the groove 24g is provided in the longitudinal direction on the surface 24d of the nip forming member 24. However, the groove 24g is not limited thereto, and may be provided in the transport direction, for example. . Further, the groove 24g may be provided in a skewed shape or a mesh shape.

  Moreover, in this Embodiment, although the nip part formation member 24 is comprised by the heat resistant resin material, it is not restricted to this, For example, you may be comprised from the porous material which has several micropores. The nip portion forming member 24 may be made of a porous material holding a lubricant.

  Accordingly, the fixing device 20 can supply the lubricant to the low friction sheet 29 from the porous gap of the nip portion forming member 24 itself in addition to the flow path 24e of the nip portion forming member 24. A large amount of lubricant can be supplied.

  Further, in the present embodiment, the flow path 24e is provided in parallel to the thickness direction. However, the present invention is not limited to this. For example, as shown in FIG. 13, the upstream side of the flow path 24e is downstream of the flow path 24e. You may form in the conveyance direction upstream rather than the side.

  Accordingly, since the fixing device 20 is inclined in the flow path 24e, the lubricant held in the lubricant supply member 30 is supplied to the surface portion 24d of the nip portion forming member 24 by gravity in addition to the capillary phenomenon. Thus, the lubricant can be supplied more reliably.

  In this embodiment, an example in which the fixing device 20 is applied to a tandem type color printer is shown. However, the fixing device 20 is an image forming device such as a facsimile machine, a copying machine, or a multifunction machine of a facsimile machine and a copying machine. You may apply to an apparatus.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 20 Fixing apparatus 21 Fixing belt (belt member)
22 Pressure roller (rotating body)
23 Heater (heat source)
24 nip part forming member 24d surface part 24e flow path 24f hole part 24g groove part 25 stay (support member)
29 Low friction sheet (low friction member)
30 Lubricant supply member L1 First predetermined interval L2 Second predetermined interval N Nip portion P Recording medium

JP 2009-003410 A

Claims (12)

A belt member having a heat source therein and bonded at both ends;
A rotating body that rotates in contact with the belt member;
A nip portion forming member that is provided on the inner peripheral surface side of the belt member and forms a nip portion between the belt member and the rotating body by contacting the rotating body via the belt member;
A lubricant supply member that is provided on the inner peripheral surface side of the belt member and holds a lubricant supplied to a surface portion of the nip portion forming member that contacts the rotating body via the belt member;
A fixing device configured to fix an image on the recording medium by heating the recording medium conveyed to the nip portion,
The nip forming member may have a passage for supplying the lubricant supplied from the lubricant supply member to the surface portion,
The flow path has a plurality of holes for supplying the lubricant to the surface portion,
A plurality of the hole portions are provided at predetermined intervals in the longitudinal direction of the nip portion forming member,
The predetermined interval is a first predetermined interval on the outer side in the longitudinal direction of the nip portion forming member and a second predetermined interval shorter than the first predetermined interval in the longitudinal center portion of the nip portion forming member. a fixing device which is characterized that you have been constructed by some and spacing. A belt member having a heat source therein and bonded at both ends;
A rotating body that rotates in contact with the belt member;
A nip portion forming member that is provided on the inner peripheral surface side of the belt member and forms a nip portion between the belt member and the rotating body by contacting the rotating body via the belt member;
A lubricant supply member that is provided on the inner peripheral surface side of the belt member and holds a lubricant supplied to a surface portion of the nip portion forming member that contacts the rotating body via the belt member;
A fixing device configured to fix an image on the recording medium by heating the recording medium conveyed to the nip portion,
The nip portion forming member has a flow path for supplying the lubricant supplied from the lubricant supply member to the surface portion,
The flow path has a plurality of holes for supplying the lubricant to the surface portion,
The hole portion is formed such that a diameter of the hole portion provided in a central portion in the longitudinal direction of the nip portion forming member is larger than a diameter of the hole portion provided outward in the longitudinal direction of the nip portion forming member. A fixing device. A belt member having a heat source therein and bonded at both ends;
A rotating body that rotates in contact with the belt member;
A nip portion forming member that is provided on the inner peripheral surface side of the belt member and forms a nip portion between the belt member and the rotating body by contacting the rotating body via the belt member;
A lubricant supply member that is provided on the inner peripheral surface side of the belt member and holds a lubricant supplied to a surface portion of the nip portion forming member that contacts the rotating body via the belt member;
A fixing device configured to fix an image on the recording medium by heating the recording medium conveyed to the nip portion,
The nip portion forming member has a flow path for supplying the lubricant supplied from the lubricant supply member to the surface portion,
The fixing device , wherein the flow path has a groove for supplying the lubricant to the surface portion . A belt member having a heat source therein and bonded at both ends;
A rotating body that rotates in contact with the belt member;
A nip portion forming member that is provided on the inner peripheral surface side of the belt member and forms a nip portion between the belt member and the rotating body by contacting the rotating body via the belt member;
A lubricant supply member that is provided on the inner peripheral surface side of the belt member and holds a lubricant supplied to a surface portion of the nip portion forming member that contacts the rotating body via the belt member;
A fixing device configured to fix an image on the recording medium by heating the recording medium conveyed to the nip portion,
The nip portion forming member has a flow path for supplying the lubricant supplied from the lubricant supply member to the surface portion,
The fixing device according to claim 1, wherein the upstream side of the flow path is formed upstream of the downstream side of the flow path in the transport direction of the recording medium . A belt member having a heat source therein and bonded at both ends;
A rotating body that rotates in contact with the belt member;
A nip portion forming member that is provided on the inner peripheral surface side of the belt member and forms a nip portion between the belt member and the rotating body by contacting the rotating body via the belt member;
A lubricant supply member that is provided on the inner peripheral surface side of the belt member and holds a lubricant supplied to a surface portion of the nip portion forming member that contacts the rotating body via the belt member;
A fixing device configured to fix an image on the recording medium by heating the recording medium conveyed to the nip portion,
The nip portion forming member has a flow path for supplying the lubricant supplied from the lubricant supply member to the surface portion,
A support member that is provided on the inner peripheral surface side of the belt member and supports the nip portion forming member in contact with the nip portion forming member;
A low friction member that is provided on the inner peripheral surface side of the belt member and reduces frictional resistance generated between the belt member and the nip forming member;
The fixing device according to claim 1, wherein the low friction member holds the lubricant supplied from the lubricant supply member . A belt member having a heat source therein and bonded at both ends;
A rotating body that rotates in contact with the belt member;
A nip portion forming member that is provided on the inner peripheral surface side of the belt member and forms a nip portion between the belt member and the rotating body by contacting the rotating body via the belt member;
A lubricant supply member that is provided on the inner peripheral surface side of the belt member and holds a lubricant supplied to a surface portion of the nip portion forming member that contacts the rotating body via the belt member;
A fixing device configured to fix an image on the recording medium by heating the recording medium conveyed to the nip portion,
The nip portion forming member has a flow path for supplying the lubricant supplied from the lubricant supply member to the surface portion,
The fixing device according to claim 1, wherein the nip portion forming member is made of a porous material having a plurality of fine holes . The fixing device according to claim 6 , wherein the nip forming member is made of the porous material holding the lubricant . The flow path fixing device according to any one of claims 3 to 7, characterized in Rukoto which having a plurality of holes for supplying the lubricant to said surface portion. The fixing device according to claim 3 , wherein a plurality of the groove portions are provided . The fixing device according to claim 1, wherein the heat source is a radiation source and directly heats the belt member with radiant heat. A support member that is provided on the inner peripheral surface side of the belt member and that supports the nip portion forming member in contact with the nip portion forming member;
A reflection plate that reflects radiant heat from the heat source between the heat source and the support member;
The fixing device according to claim 1, wherein the heat source directly heats the fixing member at a portion other than the nip portion. An image forming apparatus comprising the fixing device according to claim 1.

Images