Patent Application
20230273557
The present invention relates to a fixing apparatus preferably used in an image forming apparatus that utilizes an electrophotographic technique, such as a printer, a copying machine, a facsimile, or a multifunction machine.
Image forming apparatuses are equipped with a fixing apparatus for fixing a toner image on a recording material by applying heat and pressure to the recording material on which the toner image is formed. The fixing apparatus includes a rotating endless fixing belt, a fixing pad arranged non-rotatably on an inner circumference side of the fixing belt, and a pressure roller abutting against an outer circumference surface of the fixing belt. In the fixing apparatus, the fixing belt is pressed by the fixing pad and the pressure roller, by which a fixing nip portion is formed between the fixing belt and the pressure roller, and heat and pressure is applied to the recording material passing through the fixing nip portion, by which the toner image is fixed to the recording material.
If frictional force between the fixing belt and the fixing pad is great, rotation of the fixing belt is obstructed. Thus, an apparatus including a slide member that slides against a fixing belt to reduce the frictional force between the fixing belt and the fixing pad at the fixing nip portion where the pressure is high is proposed (Japanese Patent Application Laid-Open Publication No. 2017-181948). Recently, a slide member having a plurality of projected portions formed on a surface thereof is used to reduce the frictional force between the fixing belt and the slide member.
In a fixing apparatus that includes a slide member having a plurality of projected portions formed on a surface thereof, a pad serving as a retaining member, and a fixing belt, the slide member must be fixed to the pad since the slide member and the pad are separate members. In a configuration where the slide member is fixed to the pad, the positioning of the slide member must be performed with high accuracy.
In consideration of the above-described problems, the present invention aims at positioning the slide member with high accuracy.
According to a first aspect of the present invention, a fixing apparatus includes a fixing belt having an endless shape and configured to rotate, a slide member including a slide surface configured to slide against an inner circumference surface of the fixing belt, an opposing member configured to form a fixing nip portion by nipping the fixing belt with the slide member, the fixing nip portion being configured to nip and convey a recording material in a conveyance direction and fix a toner image on the recording material, and a retaining member including a groove portion fitting the slide member therein, the groove portion retaining the slide member. The retaining member contacts the inner circumference surface of the fixing belt at a position downstream from the fixing nip portion in the conveyance direction. The retaining member includes, in the groove portion, a bottom surface portion that is in contact with an opposite surface of the slide member from the slide surface, a side surface portion that is formed on a downstream side of the groove portion in the conveyance direction and intersecting the bottom surface portion, and a continuous portion that is formed between the bottom surface portion and the side surface portion. The slide member includes an abutment portion configured to abut against the side surface portion at a position downstream from a downstream edge of the opposite surface in a state where the slide member is slidden against the fixing belt such that the downstream edge of the opposite surface is positioned upstream from the continuous portion in the conveyance direction.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
A fixing apparatus according to a present embodiment will be described. At first, a general configuration of an image forming apparatus that is preferable for adopting the fixing apparatus according to the present embodiment will be described with reference to
An image forming apparatus 1 is a full-color printer adopting an electrophotographic system that includes four image forming units Pa, Pb, Pc, and Pd disposed to correspond to four colors, which are yellow, magenta, cyan, and black. The present embodiment is a tandem-type image forming apparatus 1 in which the image forming units Pa, Pb, Pc, and Pd are arranged along a direction of rotation of an intermediate transfer belt 204 described below. The image forming apparatus 1 forms a toner image on a recording material according to an image signal from a document reading apparatus 2 connected to an apparatus body 3 of the image forming apparatus 1 or a host apparatus such as a personal computer connected in a communicatable manner to the apparatus body 3. Examples of the recording material include paper, plastic films, cloths and other sheet materials.
As illustrated in
The apparatus body 3 is equipped with a plurality of image forming units Pa, Pb, Pc, and Pd, and image is formed in each image forming unit based on the above-mentioned image signals. That is, the image signals are converted into laser beams that have been subjected to pulse width modulation control (PWM) by the control unit 30. A polygon scanner 31 serving as an exposing unit scans laser beams corresponding to image signals. Then, laser beams are irradiated to photosensitive drums 200a to 200d serving as image bearing members of the respective image forming units Pa to Pd.
The image forming units form toner images of corresponding colors, wherein the image forming unit Pa forms a yellow (Y) toner image, the image forming unit Pb forms a magenta (M) toner image, the image forming unit Pc forms a cyan (C) toner image, and an image forming unit Pd forms a black (Bk) toner image. These image forming units Pa to Pd adopt an approximately identical configuration, such that the following description will describe the image forming unit Pa for forming a yellow (Y) toner image, and the descriptions on the other image forming unit Pb to Pd are omitted. In the image forming unit Pa, a toner image is formed on the surface of the photosensitive drum 200a based on image signals.
A charging roller 201a serving as a primary charger charges a surface of the photosensitive drum 200a to predetermined potential and prepares for the formation of an electrostatic latent image. The electrostatic latent image is formed on the surface of the photosensitive drum 200a charged to predetermined potential by laser beams from the polygon scanner 31. A developing unit 202a develops the electrostatic latent image on the photosensitive drum 200a and forms a toner image. A primary transfer roller 203a performs discharge from a rear side of the intermediate transfer belt 204, applies a primary transfer bias of opposite polarity as toner, and transfers the toner image on the photosensitive drum 200a to the intermediate transfer belt 204. The surface of the photosensitive drum 200a after transfer is cleaned by a cleaner 207a.
Further, the toner image on the intermediate transfer belt 204 is conveyed to the subsequent image forming units, where toner images of respective colors formed in each of the image forming units are sequentially transferred in the order of Y, M, C, and Bk, such that a four-color image is formed on the surface thereof. The toner image having passed through the image forming unit Pd of Bk which is positioned most downstream in a direction of rotation of the intermediate transfer belt 204 is conveyed to a secondary transfer portion T2 composed of a secondary transfer roller pair 205, 206. Thereafter, by having a secondary transfer electric field having opposite polarity as the toner image on the intermediate transfer belt 204 is applied at the secondary transfer portion T2, by which a toner image is secondarily transferred from the intermediate transfer belt 204 to the recording material.
The recording material is stored in a cassette 9, and the recording material fed from the cassette 9 is conveyed to a registration portion 208 composed of a pair of registration rollers, for example, where it stands by at the registration portion 208. Thereafter, the timing at the registration portion 208 is controlled such that the toner image on the intermediate transfer belt 204 corresponds to the paper position, and the recording material is conveyed to the secondary transfer portion T2.
The recording material having the toner image transferred thereto at the secondary transfer portion T2 is conveyed to a fixing apparatus 8, and heat and pressure is applied at the fixing apparatus 8, by which the toner image borne on the recording material is fixed to the recording material. The recording material having passed through the fixing apparatus 8 is discharged onto a sheet discharge tray 7. When forming images on both sides of the recording material, after completing transferring and fixing of a toner image to a first surface, i.e., front surface, the surface of the recording material is reversed via a reverse conveyance portion 10, and transferring and fixing of a toner image to a second surface, i.e., rear surface, of the recording material is performed before the recording material is stacked on the sheet discharge tray 7.
The control unit 30 performs control of the entire image forming apparatus 1, as described above. Further, the control unit 30 is capable of performing various settings based on an input from an operation unit 4 included in the image forming apparatus 1. The control unit 30 includes a Central Processing Unit (CPU), a Read Only Memory (ROM), and a Random Access Memory (RAM). The CPU performs control of various units by reading programs corresponding to the control procedures stored in the ROM. The RAM stores work data and input data, and the CPU refers to the data stored in the RAM based on the programs described above and performs control.
Next, the configuration of the fixing apparatus 8 according to the present embodiment will be described with reference to
The fixing apparatus 8 includes a fixing belt 301 that is endless and rotatable, the pressure roller 305 that abuts against the fixing belt 301 and that serves as an opposing member that forms the fixing nip portion N together with the fixing belt 301, a heating roller 307, and a fixing pad unit 300.
The fixing belt 301 is arranged in a replaceable manner in the fixing pad unit 300. The fixing belt 301 has thermal conductivity and heat-resisting property, and it is formed in a thin cylindrical shape. In the present embodiment, the fixing belt 301 adopts a three-layer structure in which a base layer 301a is disposed on an inner circumference side, an elastic layer 301b is arranged on an outer circumference of the base layer 301a, and a release layer 301c is formed on an outer circumference thereof, as illustrated in
The pressure roller 305 is supported rotatably on a fixing frame (not shown) of the fixing apparatus 8, wherein a gear (not shown) is fixed to one end portion thereof in a width direction, and the pressure roller 305 is driven to rotate by being connected via the gear to a drive source such as a motor (not shown). In a state where the pressure roller 305 is rotated, rotational force of the pressure roller 305 is transmitted to the fixing belt 301 by frictional force generated at the fixing nip portion N. Thereby, the fixing belt 301 is rotated following the rotation of the pressure roller 305. That is, the pressure roller 305 is an example of an opposing member configured to form a fixing nip portion N by nipping the fixing belt 301 with the slide member 304. The fixing nip portion N is configured to nip and convey a recording material in the conveyance direction and fix a toner image on the recording material.
The pressure roller 305 has an elastic layer 305b formed on an outer circumference of a rotation shaft 305c, and a release layer 305a is formed on an outer circumference of the elastic layer 305b, as illustrated in
As illustrated in
The heating roller 307 is arranged on an inner circumference side of the fixing belt 301, and stretches the fixing belt 301 together with the fixing pad unit 300. The heating roller 307 is formed in a cylindrical shape of metal such as aluminum and stainless steel, and a halogen heater 306 serving as a heat source for heating the fixing belt 301 is arranged in the inner side thereof. The heating roller 307 is heated to a predetermined temperature by the halogen heater 306.
In the present embodiment, the heating roller 307 is formed of an aluminum pipe having a thickness of “1 mm”, for example, from the viewpoint of thermal conductivity, and a surface layer thereof is subjected to anodizing treatment. The number of the halogen heater 306 can be one, but from the viewpoint of facilitating temperature distribution control of the heating roller 307 in the rotational axis direction, i.e., width direction, a plurality of halogen heaters 306 are desirably provided. The plurality of halogen heaters 306 have mutually varying light distributions in the width direction, and according to the size of the recording material, a lighting ratio is controlled by the control unit 30 (refer to
The heating roller 307 can have a pivot axis arranged either on one end or near a center of the rotational axis direction, i.e., width direction, and that swings so as to generate a tension difference between one side and the other side of the fixing belt 301 in the width direction to thereby move the fixing belt 301 in the width direction. That is, the fixing belt 301 may be skewed to one side of the end portions in the width direction, which is so-called belt skew, during rotation, due to a diametral accuracy of the heating roller 307 stretching the belt or an alignment accuracy with a fixing pad 303 described later. Therefore, by swinging the heating roller 307, the position of the fixing belt 301 in the rotational axis direction, i.e., skew position, is controlled. Further, the heating roller 307 is urged by a spring supported on a frame (not shown) of the fixing apparatus 8, and it can also serve as a tension roller for applying a predetermined tension to the fixing belt 301.
Next, the fixing pad unit 300 will be described. As illustrated in
In the present embodiment, the fixing belt 301 is pressed toward the pressure roller 305 from the inner circumference side by the fixing pad 303 supported on the fixing stay 302. Thereby, the fixing nip portion N having a wide nip with sufficient conveyance direction length and width direction length is formed between the pressure roller 305 and the fixing belt 301. Further, by having the fixing pad 303 made of resin supported by the fixing stay 302 made of metal having a greater rigidity, deflection of the fixing pad 303 caused by the pressure received during pressing operation is reduced, such that a uniform fixing nip width in the width direction can be obtained.
The fixing pad 303 serving as a retaining member is disposed non-rotatably on an inner circumference side of the fixing belt 301 and includes a groove portion 303f (refer to
As illustrated in
If frictional force between the fixing belt 301 and the fixing pad 303 is great, the rotation of the fixing belt 301 is obstructed. Therefore, according to the present embodiment, as illustrated in
The slide member 304 has a heat-resisting property and strength, and is provided with a slide surface that abuts against the inner circumference surface of the fixing belt 301 being rotated and slides against the fixing belt 301 in a state retained by the fixing pad 303. By interposing the slide member 304 between the fixing pad 303 and the fixing belt 301, frictional force between the fixing pad 303 and the fixing belt 301 is reduced, such that the rotation of the fixing belt 301 is not obstructed by the fixing pad 303. A lubricant for smoothly sliding the fixing belt 301 against the slide member 304 can be applied on the inner circumference surface of the fixing belt 301. For example, a silicone oil can be used as the lubricant.
As described above, according to the present embodiment, frictional force between the fixing pad 303 and the fixing belt 301 is reduced by the slide member 304, and according to the present embodiment, the slide member 304 has a slide surface that slides against the fixing belt 301 formed in a concave-convex shape or an embossed shape, as illustrated in
The slide member 304 is formed of a metal material such as stainless steel (SUS), copper, or aluminum. In the case of the present embodiment, a stainless steel (SUS) having a thickness of “1 mm” is used to form the slide member 304. The slide member 304 is not limited to metal, and it can be formed using engineering plastics such as polyimide resin (PI), polyether ether ketone resin (PFFK), or LCP (liquid crystal polymer resin).
As illustrated in
Further, a low friction layer 304c for reducing frictional force generated between the fixing belt 301 is provided on the surface of the slide member 304 using polytetrafluoroethylene resin (PTFE), or PFA, for example. In the present embodiment, a PTFE with a thickness of “20 μm” is coated on the surface of the base 304a and the projected portions 304b.
As illustrated in
As described above, the fixing pad 303 retains the slide member 304 such that the inner circumference surface of the fixing belt 301 slides against the tip surface of the projected portions 304b. In order to do so, the groove portion 303f having a recessed shape is formed on the fixing pad 303 for fitting and retaining the slide member 304 on the opposite side from the side being supported by the fixing stay 302. The fixing pad 303 is manufactured by injection-molding a resin material using a mold.
Here, as described above, if the height of the plurality of projected portions 304b on the slide member 304 is not uniform, pressure unevenness may be generated in the fixing nip portion N and fixing failures of the recording material may occur. The height difference of the projected portions 304b that causes fixing failures is, for example, approximately 20 to 50 μm. In order to prevent fixing failures of the recording material caused by the height of the projected portions 304b, for example, a contactless inspection apparatus by laser scanning is used to measure the heights of the plurality of projected portions 304b and perform inspection of the slide member 304. The contactless inspection apparatus measures the heights of the projected portions 304b by a line scanning sensor, called a scan sensor, using laser light, and compares the measured values with a reference value that is provided in a projected portion shape profile prepared in advance. Then, if the difference between the measured values and the reference value is within a predetermined range, such as 15 μm or less, it is determined that the slide member 304 is a good product. The slide member 304 that is not determined as a good product will not be used.
When the slide member 304 is formed of a base material such as stainless steel, the slide member 304 may be warped from a center portion in the width direction, i.e., longitudinal direction, due to the accuracy of the base material or the residual stress during processing of the base material. The difference in heights of the end portions and the center portion in the width direction caused by warping is approximately “2 mm”, for example, though it may vary among the individual slide members 304. If the slide member 304 is warped, it is difficult to measure the height of the projected portions 304b using the contactless inspection apparatus with high accuracy, so that it is necessary to measure the height of the projected portions 304b after straightening the warping of the slide member 304. In order to straighten the warping of the slide member 304, the slide member 304 is nipped between and fixed, i.e., clamped, by the surface plate 500 and clamp members 501, as described below.
As illustrated in
In the present embodiment, the first planar area 3041 and the second planar area 3042 are clamped, such that the heights of the projected portions 304b are measured in a state where the warping of the slide member 304 is straightened. The first planar area 3041 and the second planar area 3042 are formed to have a length (L1, L2) that allows clamping to be performed without interfering with the projected portions 304b in the conveyance direction. For example, the first planar area 3041 is formed to have a length “L1” that is “0.5 mm” or more from a first end portion positioned most downstream of the base 304a in the short direction, i.e., conveyance direction. Similarly, the second planar area 3042 is formed to a have a length “L2” that is “0.5 mm” or more from a second end portion positioned most upstream of the base 304a in the short direction, i.e., conveyance direction. Thereby, the heights of the projected portions 304b can be measured with high accuracy in a state where the warping of the slide member 304 is straightened.
In order to clamp the slide member 304 reliably and straighten the warping thereof, the conveyance direction length of the first planar area 3041 and the second planar area 3042 is preferably “1.0 mm” or more. Further, the first planar area 3041 and the second planar area 3042 are preferably formed across the entire area in the width direction, i.e., entire area in the longitudinal direction, of the slide member 304.
As illustrated in
Meanwhile, as illustrated in
In the case of the slide member 304 of the present embodiment, as illustrated in
As described above, from the viewpoint of clamping the slide member 304 infallibly, the conveyance direction length of the first planar area 3041 and the second planar area 3042 (L1, L2) is “0.5 mm” or more, preferably “1.0 mm” or more. However, if the conveyance direction length of the first planar area 3041 and the second planar area 3042 (L1, L2) is longer than necessary, the conveyance direction length of the fixing nip portion N (refer to
In view of the above-mentioned points, according to the present embodiment, the conveyance direction length of the first planar area 3041 and the second planar area 3042 is set to “2.0 mm” or less. That is, the first planar area 3041 and the second planar area 3042 are arranged within a range of 0.5 mm or more and 2.0 mm or less from both edges of the slide member 304 in the conveyance direction. In conclusion, the conveyance direction length of the first planar area 3041 and the second planar area 3042 is “0.5 mm or more and 2.0 mm or less”, preferably “1.0 mm or more and 1.5 mm or less”.
The conveyance direction lengths of the first planar area 3041 and the second planar area 3042 do not have to be the same. The second planar area 3042 arranged upstream of the fixing nip portion N has smaller influence on the separability of the above-mentioned recording material compared to the first planar area 3041 arranged downstream of the fixing nip portion N. Therefore, the conveyance direction length of the second planar area 3042 is preferably longer than that of the first planar area 3041 (L2>L1).
As described, the slide member 304 according to the present embodiment includes the first planar area 3041 and the second planar area 3042 where the projected portions 304b are not formed and that do not contact the fixing belt 301 in the range of “0.5 mm or more and 2.0 mm or less” from each of the both edges of the slide member 304 in the conveyance direction. By clamping the first planar area 3041 and the second planar area 3042, the heights of the projected portions 304b can be measured correctly in a state where the warping of the slide member 304 is straightened, and scratches and dents are not formed on the projected portions 304b. Thus, the occurrence of fixing failures on the recording material caused by the projected portions 304b formed on the surface of the slide member 304 can be suppressed without deteriorating the separability of the recording material having passed through the fixing belt 301.
Next, a slide member according to a second embodiment will be described based on
If the recording material contacts the fixing belt 301 at an upstream side or a downstream side of the fixing nip portion N, fixing failures may occur. In order for the recording material not to be in contact the fixing belt 301 even if waving or deformation of the recording material occurs, the fixing belt 301 should be guided away from the pressure roller 305 at the upstream or the downstream of the fixing nip portion N by the fixing pad 303. That is, the upstream-side guide portion 303c and the downstream-side guide portion 303b of the fixing pad 303 are designed to be positioned away from the pressure roller 305 at the upstream and the downstream of the fixing nip portion N. In that case, however, according to the slide member 304 of the first embodiment described above, the upstream edge portion or the downstream edge portion of the base 304a comes to be in contact with the fixing belt 301, which may accelerate wear of the fixing belt 301 and shorten the replacement timing of the fixing belt 301.
Therefore, as according to a slide member 304G of the second embodiment illustrated in
In the present embodiment, the first planar area 3041 and the second planar area 3042 are formed to have a thickness (H2) of “30% or more and 70% or less” of a thickness (H1) from a tip of the projected portions 304b to an opposite surface 304a2 of the base 304a on an opposite side of the surface 304a1. That is, the first areas (3041, 3042) are formed to have a thickness of 30% or more and 70% or less of a thickness of a portion of the slide member 304 at which one of the plurality of the projected portions 304b is provided. For example, if the thickness (H1) from a tip of the projected portions 304b to the opposite surface 304a2 of the base 304a is “1.4 mm”, the thickness (H2) of the first planar area 3041 and the second planar area 3042 is “0.5 mm or more and 0.9 mm or less”. That is, the first planar area 3041 and the second planar area 3042 are disposed such that the distance from the first planar area 3041 and the second planar area 3042 to the pressure roller 305 is longer than the distance from a part of the slide member 304G opposed to a center portion of the fixing nip portion N to the pressure roller 305. In the direction toward the pressure roller 305 from the fixing pad 303, a downstream end portion of the second area 3045 is protruded toward the pressure roller 305 from downstream end portions of the first areas (3041, 3042).
The thickness of the first planar area 3041 and the second planar area 3042 does not have to be the same. Regarding the second planar area 3042 arranged upstream of the fixing nip portion N, it is less affected by the waving and deformation of the recording material compared to the first planar area 3041 arranged downstream of the fixing nip portion N. Therefore, the thickness of the second planar area 3042 can be made greater than the thickness of the first planar area 3041.
According to this configuration, even in a case where the fixing pad 303 is provided to prevent the recording material from being in contact with the fixing belt 301, an effect of suppressing the occurrence of fixing failures on the recording material caused by the projected portions 304b on the slide member 304 can be realized without deteriorating the separability of the recording material.
When forming the fixing pad 303 through injection molding, round chamfering is performed to round corners of the tip of projected portions formed in the mold for the groove portion 303f to ensure releasability from the mold and to prevent damaging of the mold. Therefore, in the fixing pad 303, a corner portion, that is, a downstream-side continuous portion 303g, of the groove portion 303f is formed to have a curved shape, that is, arc shape or rounded corner (refer to
If the corner portion of the groove portion 303f is formed in a curved shape, as described above, fixing failures of the toner image on the recording material may occur. This point will be described with reference to a slide member 3040 of a comparative example illustrated in
As illustrated in
As illustrated in
When the corner portion 3043 is moved in contact with the downstream-side continuous portion 303g, the slide member 3040 is moved away from the bottom surface 303h along the downstream-side continuous portion 303g. That is, as illustrated, the slide member 3040 is retained by the fixing pad 303 in a state where a portion of the opposite surface 304e is not in contact with the bottom surface 303h. This is an unstable state in which a gap is formed between the bottom surface 303h of the groove portion 303f and the slide member 3040. In this case, a desired nip pressure distribution cannot be obtained in the fixing nip portion N and pressure unevenness tends to occur, according to which fixing failures of toner image on the recording material may occur.
In view of the above point, the present embodiment proposes a configuration in which the slide member 304 is retained in a stable state by the fixing pad 303 even if the corner portion, i.e., the downstream-side continuous portion 303g, of the groove portion 303f is formed in a curved shape. The present embodiment will be described below based on
As illustrated in
According to the present embodiment, the downstream-side abutment portion 310 is formed by providing a downstream-side end surface of the slide member 304 formed as an inclined surface 304d1 that is inclined downstream toward a slide surface, i.e., tip surface of the projected portions 304b, from the opposite surface 304e. That is, the inclined surface 304d1 that is inclined such that a more downstream portion thereof in the conveyance direction is toward the slide surface from the opposite surface 304e. Compared to the slide member 3040 (refer to
As described, according to the present embodiment, the downstream-side abutment portion 310 is formed in the slide member 304. In a state where the downstream-side abutment portion 310 is in contact with the downstream-side side surface 303e of the fixing pad 303, the slide member 304 is retained by the fixing pad 303 in a state where the downstream edge 3044 of the opposite surface 304e is positioned upstream of the downstream-side continuous portion 303g. When the slide member 304 is moved downstream along with the starting of rotation of the fixing belt 301, the downstream-side abutment portion 310 abuts against the downstream-side side surface 303e before the downstream edge 3044 of the opposite surface 304e comes into contact with the downstream-side continuous portion 303g, and the slide member 304 is stopped. That is, since the corner portion, i.e., the downstream edge 3044, is not moved while being in contact with the downstream-side continuous portion 303g, the slide member 304 will not be separated from the bottom surface 303h. Thereby, the slide member 304 is retained by the fixing pad 303 with the entire area of the opposite surface 304e in contact with the bottom surface 303h. This is a stable state in which no gap is formed between the bottom surface 303h of the groove portion 303f and the slide member 304. Accordingly, a desirable nip pressure distribution can be obtained in the fixing nip portion N, and pressure unevenness is not likely to occur, such that as a result, the occurrence of fixing failures of toner image on the recording material can be suppressed.
The embodiment described above illustrated an example in which the downstream-side abutment portion 310 is composed of the inclined surface 304d1 in which the downstream-side end surface of the slide member 304 is inclined, but the present technique is not limited thereto. For example, a configuration can be adopted in which a protruded downstream-side abutment portion is formed to protrude from the downstream-side end surface of the slide member 304 across the width direction. In that case, the downstream-side abutment portion can abut against the downstream-side side surface 303e of the fixing pad 303 at a position more distant from the bottom surface 303h than the edge of the rounded corner of the downstream-side continuous portion 303g, that is, a boundary W between the downstream-side side surface 303e and the end of curve of the corner portion (refer to
According to the embodiment described above, an example is illustrated of a case where the downstream-side abutment portion 310 is formed downstream in the conveyance direction of the slide member 304, but a similar upstream-side abutment portion can also be formed upstream in the conveyance direction thereof. In that case, the description on the downstream-side abutment portion 310 described above with reference to
The embodiments described above are not limited to the configuration of heating the fixing belt 301, and the present technique is applicable to a configuration in which a pressing belt in the shape of a belt is used instead of the pressure roller 305, wherein the pressing belt is heated by a heater.
The present technique enables to realize a configuration in which projected portions that slide against the fixing belt is formed on the slide member, wherein the occurrence of fixing failures on the recording material caused by the projected portions can be suppressed with a simple configuration.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2022-028923 and 2022-028928, filed on Feb. 28, 2022 which are hereby incorporated by reference herein in their entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-028923 | Feb 2022 | JP | national |
| 2022-028928 | Feb 2022 | JP | national |
