JP2020073980A - Fixing device and image forming apparatus - Google Patents

Abstract

To provide a fixing device that can prevent a reduction in reflecting performance of a reflecting unit that reflects heat from heat sources, and an image forming apparatus.SOLUTION: The present invention relates to an image forming apparatus comprising a fixing device that fixes a developer image formed on a medium. The fixing device of the present invention includes a fixing belt, heat sources that heat the fixing belt, a reflecting unit that reflects heat from the heat sources, and a frame. The reflecting unit has a reflecting member that reflects the heat from the heat sources, and a heat radiation member that is arranged on a surface of the reflecting member on the opposite side of a surface facing the heat sources and radiates heat of the reflecting member. The frame is formed of support parts that support one end in the longitudinal direction of the reflecting unit, and attachment grooves that penetrate the other end of the reflecting unit.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fixing device and an image forming apparatus, and can be applied to, for example, an electrophotographic image forming apparatus that fixes a toner image transferred on a medium by heat and pressure.

  2. Description of the Related Art Conventionally, an electrophotographic image forming apparatus is known in which a developer image (toner image) is fixed on the surface of a medium (for example, paper) to form an image.

  As a conventional fixing device, for example, there is a device described in Patent Document 1. The fixing device described in Patent Document 1 includes a fixing belt, a halogen lamp as a heat source for heating the fixing belt, and a roller for rotating the fixing belt and forming a nip portion for sandwiching a medium. There is. Further, the fixing device described in Patent Document 1 also has a reflecting plate (reflecting portion) that reflects the heat from the heat source toward the fixing belt. In the conventional fixing device, the reflection plate is provided to promote efficient heating of the fixing belt.

JP, 2005-87624, A

  However, in the conventional fixing device, when the temperature of the reflection plate exceeds a predetermined value, the surface of the reflection plate changes, and the reflection performance tends to deteriorate (degrade).

  Therefore, there is a demand for a fixing device and an image forming apparatus that can suppress deterioration of the reflection performance of a reflecting portion that reflects heat from a heat source.

  A fixing device according to a first aspect of the present invention includes (1) a fixing belt, (2) a heat source that heats the fixing belt, (3) a reflecting portion that reflects heat from the heat source, and (4) a frame. And (5) the reflecting portion is disposed on a surface opposite to a surface of the reflecting member that reflects heat from the heat source (5-1) and a surface of the reflecting member that faces the heat source. A heat dissipation member that dissipates the heat of the reflection member, and (6) a mounting portion that supports one end in the longitudinal direction of the reflection portion and the other end of the reflection portion is attached to the frame. A groove is formed.

  A fixing device according to a second aspect of the present invention includes (1) a fixing belt, (2) a heat source for heating the fixing belt, (3) a reflecting portion for reflecting heat from the heat source, and (4) the above The reflection part includes (4-1) a reflection member that reflects heat from the heat source, and (4-2) heat of the reflection member that is arranged on a surface opposite to a surface of the reflection member that faces the heat source. (5) The heat radiation member is formed of a material having a melting point higher than that of the reflection member.

  An image forming apparatus according to a third aspect of the present invention is an image forming apparatus including a fixing device for fixing a developer image formed on a medium, wherein the fixing device according to the first or second aspect of the present invention is applied as the fixing device. Is characterized by.

  According to the present invention, it is possible to provide a fixing device and an image forming apparatus capable of suppressing a decrease in reflection performance of a reflection portion that reflects heat from a heat source.

FIG. 3 is a schematic cross-sectional view of the fixing device according to the embodiment. 1 is a schematic sectional view of an image forming apparatus according to an exemplary embodiment. It is a figure shown about the composition of the 1st reflective part concerning an embodiment. It is a figure shown about the composition of the 2nd reflective part concerning an embodiment. FIG. 3 is a perspective view of an upper unit that constitutes the fixing device according to the exemplary embodiment. It is a side view (the 1) of the unit (frame) concerning an embodiment. It is a side view (the 2) of the unit (frame) concerning an embodiment. It is explanatory drawing shown about the attachment structure of the 1st reflective part which concerns on embodiment. It is explanatory drawing shown about the attachment structure of the 2nd reflection part which concerns on embodiment.

(A) Main Embodiment Hereinafter, one embodiment of the fixing device and the image forming apparatus according to the present invention will be described in detail with reference to the drawings. In this embodiment, a case where the present invention is applied to an electrophotographic color printer will be exemplified.

(A-1) Configuration and Operation of Embodiment FIG. 2 is a schematic configuration diagram showing an internal configuration of the image forming apparatus according to this embodiment.

  The image forming apparatus 100 according to this embodiment is roughly classified into a medium holder 1, a paper feed conveyance path 2, a medium cutting section 3, a medium slack control conveyance path 4, a write timing adjustment conveyance path 5, an image forming section 6, and an intermediate portion. It has a transfer belt unit 7, a fixing device 8, and a discharge conveyance path 9.

  In this embodiment, a case where the medium is roll-shaped continuous paper (roll paper) is illustrated.

  The medium holder 1 is inserted into a paper core of a paper P, which is a roll-shaped continuous paper such as a roll paper, and rotatably stores the paper P. The paper P, which is a continuous paper, may be capable of double-sided printing or single-sided printing. Further, as the paper P, one side may be a release material, and release paper (for example, label paper or the like) that forms a label by printing an image on the printing surface of the release material may be used. The paper P stored in the medium holder 1 is set on the first feeding roller pair 202, for example, as shown by the solid line in FIG. 2, and the surface of the paper P in the direction of the arrow B1 (that is, a roll-like shape). The outer peripheral surface of the paper P may be set as the printing surface, or the paper P may be set on the first delivery roller pair 202 as indicated by the broken line in FIG. The surface in the direction (that is, the inner peripheral surface of the roll-shaped paper P) may be set as the printing surface.

  The paper feeding / transporting path 2 is a portion for feeding the paper P from the medium holder 1. The sheet feeding / conveying path 2 has an entrance sensor 201, a first feeding roller pair 202, a medium edge detection sensor 203, and a second feeding roller pair 204.

  When the entrance sensor 201 on the medium holder 1 side of the paper feed conveyance path 2 detects that the front end of the paper P from the medium holder 1 has been inserted, the first feeding roller pair 202 driven by, for example, a driving unit, causes the paper feed roller pair 202 to move the paper. The medium P is fed in the transport direction A, the medium edge detection sensor 203 detects the leading end position of the fed sheet P, and is fed to the second feeding roller pair 204.

  A medium cutting unit 3 that cuts the paper P at an arbitrary position is disposed on the downstream side of the second feeding roller pair 204. The medium cutting unit 3 has a fixed blade 301 and a rotary blade 302 that is rotated by, for example, driving means. When the rotary blade 302 rotates in the direction of arrow C with respect to the fixed blade 301, the fixed blade 301 and the rotary blade 302 sandwich and cut the paper P.

  The medium slack control / conveyance path 4 detects the position of the traveling sheet and gives slack to the traveling sheet P in accordance with the traveling position of the sheet. The medium slack control transport path 4 has a slack control roller pair 403, a transport roller pair 404, a slack detection lever 405 as a slack detection member, and a traveling position detection unit 406.

  The writing timing adjustment conveyance path 5 is arranged continuously with the medium slack control conveyance path 4 and is a part for adjusting the timing of feeding the paper P to the secondary transfer roller 707 of the intermediate transfer belt unit 7. The writing timing adjustment conveyance path 5 has a first medium leading edge detection sensor 501, a timing adjustment roller pair 502, and a second medium leading edge detection sensor 503.

  In the write timing adjustment conveyance path 5, the first medium front end detection sensor 501 detects the front end of the paper P conveyed from the conveyance roller pair 404, and the second medium front end detection sensor 503 conveys from the timing adjustment roller pair 502. The leading edge of the paper P to be printed is detected. Further, based on the sensor information from the first medium leading edge detection sensor 501 and the second medium leading edge detection sensor 503 and the information regarding the rotational operation state of the intermediate transfer belt unit 7, the intermediate transfer belt of the intermediate transfer belt unit 7 is transferred. The developer image formed on the sheet 701 is synchronized so that it can be transferred to a predetermined position on the surface of the paper P, and the timing adjustment roller pair 502 sends out the paper P.

  The image forming unit 6 forms a developer image (toner image) based on print data on the intermediate transfer belt 701 of the intermediate transfer belt unit 7. The image forming apparatus 100 according to this embodiment is a color printer using an electrophotographic process. Therefore, in the image forming unit 6 of this embodiment, an image is formed such that yellow (Y), magenta (M), cyan (C), black (K), and the like, each of which has a different color of developer (toner). The forming units 6Y, 6C, 6M, and 6K are mounted on the upper portion of the intermediate transfer belt unit 7.

  The image forming units 6Y, 6C, 6M, and 6K sequentially form developer images with different developer colors on the intermediate transfer belt 701 that rotates counterclockwise in FIG.

  The intermediate transfer belt unit 7 receives the transfer of the developer image formed by the image forming unit 6 (image forming units 6Y, 6C, 6M, and 6K), and further, in synchronization with the writing timing adjusting conveyance path 5, the paper is transferred. The developer image is transferred to P.

  The intermediate transfer belt unit 7 faces a drive roller 702 driven by, for example, a drive unit, a tension roller 703 that applies tension to the intermediate transfer belt 701 by an urging unit such as a coil spring, and a secondary transfer roller 707. It has a secondary transfer backup roller 704 for transferring the developer image to P and an intermediate transfer belt 701 stretched around various rollers.

  The intermediate transfer belt unit 7 has a developer image formed by each of the image forming units 6Y, 6M, 6C and 6K at a position facing the image forming units 6Y, 6M, 6C and 6K of the image forming unit 6. Is provided on the surface of the intermediate transfer belt 701, a primary transfer roller 705 for applying a predetermined voltage is provided.

  The discharge conveyance path 9 is arranged continuously with the fixing device 8 and has a conveyance detection sensor 901 and a conveyance roller pair 902. The conveyance detection sensor 901 detects passage of the paper P on which the image is fixed by the fixing device 8, and the conveyance roller pair 902 conveys the paper P after fixing to the discharge conveyance path 903 and discharges the paper P to the outside of the machine. ..

  The fixing device 8 applies heat and pressure to the toner image (developer image) on the sheet P sent from the secondary transfer roller 707 and the secondary transfer backup roller 704 of the intermediate transfer belt unit 7 to melt the toner image. Then, the image is fixed on the paper P.

  FIG. 1 is a schematic sectional view of the fixing device 8.

  The fixing device 8 has a roller drive 803 as a fixing roller and a roller pressure 804 as a pressure roller. The roller drive 803 and the roller pressure 804 are arranged to face each other. The roller pressure 804 is biased in the direction of the roller drive 803, and forms a nip portion N with the roller drive 803. The nip portion N is a contact portion between the roller drive 803 and the roller pressure 804, and is also called a fixing nip portion. The sheet P from the image forming unit 400 passes through the nip portion N and is discharged. At this time, the roller drive 803 and the roller pressure 804 apply heat and pressure to the unfixed toner image on the paper P at the nip portion N to fix the toner image on the paper P.

  Each member of the roller drive 803 and the roller pressure 804 is attached to the frame of the fixing device 8.

  As shown in FIG. 1, an endless fixing belt or a belt 801 as a first belt is arranged outside the roller drive 803. Further, an endless pressing belt or a belt 802 as a second belt is arranged outside the roller pressure 804.

  That is, in the nip portion N, the belt 801 and the belt 802 are sandwiched between the roller drive 803 and the roller pressure 804. In other words, the roller drive 803 and the roller pressure 804 are in pressure contact with each other via the belt 801 and the belt 802.

  The belt 801 is provided with two roller supports 808 and 809 as support members (stretching members). That is, the belt 801 is stretched around the roller drive 803 and the roller supports 808 and 809. As shown in FIG. 1, in the belt 801, the roller support 808 is arranged on the upper side, and the roller drive 803 and the roller support 809 are arranged on the lower side.

  The belt 801 moves along the medium transport direction, which is the direction in which the paper P is transported, and applies heat to the unfixed toner image on the transported paper P. Specifically, the belt 801 is rotatably arranged and rotationally moves in a predetermined rotation direction. The belt 801 rotates (moves) as the roller drive 803 rotates. The belt 802 is driven to rotate (move) by the friction force with the belt 801. Specifically, the belt 802 rotates (moves) in a predetermined direction as the belt 801 rotates (moves). Further, as the belt 802 rotates, the roller pressure 804 inscribed in the belt 802 also rotates. The belts 801 and 802 extend in the longitudinal direction (direction orthogonal to the side of FIG. 1) orthogonal to the medium transport direction. The belts 801 and 802 have elasticity.

  Inside the belt 801, two halogen lamps 805 and 806 are arranged as a heat source for heating the belt 801. Further, one halogen lamp 807 is arranged inside the belt 802.

  In the fixing device 8, many heat sources are arranged on the belt 801 side as a fixing belt in order to mainly heat the toner image transferred onto the upper surface of the paper P. However, the number and types of heat sources arranged in each belt. Are not limited.

  Similarly, the belt 802 is also provided with two roller supports 810, 810 as support members (stretching members). That is, the belt 801 is stretched around the roller pressure 804 and the roller supports 810 and 811. As shown in FIG. 1, in the belt 802, the roller pressure 804 and the roller support 810 are arranged on the upper side (nip portion N side), and the roller support 811 is arranged on the lower side.

  Inside the belt 801, two reflection units 1000 and 1100 that reflect heat (or light) from the heat (or light) of the halogen lamps 805 and 806 toward the belt 801 are arranged. The reflection unit 1000 is arranged above the halogen lamps 805 and 806 and between the halogen lamps 805 and 806 and the roller support 808. The reflector 1100 is arranged below the halogen lamps 805 and 806 and between the halogen lamps 805 and 806 and the lower members (roller drive 803 and roller support 809). In other words, the two reflectors 1000 and 1100 are arranged so as to face the halogen lamps 805 and 806. That is, the reflection units 1000 and 1100 increase the efficiency of heating the belt 801 by reflecting the heat (or light) of the halogen lamps 805 and 806, and also to other members (roller drive 803, roller supports 808 and 809). Direct transfer of heat (radiant heat) from the halogen lamps 805 and 806 is suppressed.

  In addition, as shown in FIG. 1, two reflecting portions 1200 and 1300 that reflect heat (or light) from the halogen lamp 807 toward the belt 802 are also arranged inside the belt 802. The reflector 1200 is arranged above the halogen lamp 807 so as to cover the roller pressure 804 and the roller support 810. The reflecting portion 1300 is arranged below the halogen lamp 807 so as to cover the arrangement between the halogen lamp 807 and the roller support 811. In other words, the two reflectors 1200 and 1300 are arranged so as to face the halogen lamp 807.

  Two thermostats 812 and 813 are arranged around the belt 801. Further, one thermostat 814 is arranged around the belt 802.

  Next, the detailed configurations of the reflecting section 1000 and the reflecting section 1100 will be described.

  The reflector 1000 is provided on the surface facing the halogen lamps 805 and 806 with a reflector 1010 as a reflecting member (reflecting plate) that easily reflects heat (or light) from the halogen lamps 805 and 806. Further, in the reflecting section 1000, a heat dissipation member (heat dissipation) for dissipating the heat of the reflector 1010 (heat dissipation) to the surface opposite to the surface facing the halogen lamps 805 and 806 (the surface facing the roller support 808). A radiator 1020 as a part) is provided.

  Similarly, the reflector 1100 is also provided with a reflector 1110 on the surface facing the halogen lamp 807 to facilitate reflection of heat (or light) from the halogen lamp 807. Further, the reflector 1100 is provided with a radiator 1120 for radiating the heat of the reflector 1110 (exhaust heat) on the surface opposite to the surface facing the halogen lamp 807 (the surface facing the roller support 811). There is.

  As shown in FIG. 1, one surface of each of the reflectors 1010 and 1110 and one surface of each of the radiators 1020 and 1120 are formed / disposed so as to be in contact with each other over the entire surface. The contact surfaces of the reflectors 1010 and 1110 and the radiators 1020 and 1120 may be fixed with an adhesive or the like, but it is preferable to fix them simply by overlapping without using an adhesive. It becomes difficult to deform.

  The material of the reflectors 1010 and 1110 is not limited as long as it is a material that easily reflects heat (or light). As a material of the reflectors 1010 and 1110, for example, a plate-shaped aluminum surface (a surface facing a heat source) on which silver deposition processing is performed can be used. For example, Milano Silver manufactured by Alanod (a material in which aluminum is vapor-deposited on the surface of aluminum) is a material having a reflectance of 98% and a very good reflective property, and thus is a material suitable for the reflectors 1010 and 1110. The melting point temperature of aluminum is about 660 ° C. When the halogen lamps 805 and 806 excessively heat the reflectors 1010 and 1110 near the melting point temperatures of the reflectors 1010 and 1110, the reflection performance may be deteriorated due to deformation or the like. Specifically, for example, as the temperature of the reflectors 1010 and 1110 rises, the surface (silver vapor-deposited surface) may be discolored and the reflection performance (reflectance) may decrease.

  Therefore, in this embodiment, the reflectors 1010 and 1110 are overlapped with the radiators 1020 and 1120 to form the reflectors 1000 and 1100, thereby suppressing the temperature rise of the reflectors 1010 and 1110.

  As the radiators 1020 and 1120, it is desirable to use a material having high thermal conductivity and higher heat resistance than the reflectors 1010 and 1110 (for example, having a high melting point temperature). Thereby, the heat radiation function of the radiators 1020 and 1120 can be ensured. Further, by using a metal material having a high heat resistance (at least a metal material having a melting point higher than that of the reflectors 1010, 1110) for the radiators 1020, 1120, the reflectors 1010, 1110 are supported, and at the same time, the reflectors 1010, 1110 have a high melting point. It can also exert the function of suppressing deformation. As the radiators 1020 and 1120, for example, a metal material such as stainless steel (for example, SUS304) can be applied. Since stainless steel (SUS) has higher rigidity and softening temperature (melting point temperature) than aluminum, it is suitable as a material applied to the radiators 1020 and 1120. Since the melting point temperature of stainless steel is 1400 or higher (1.5 times or more the melting point temperature of aluminum), it is suitable as a material for the radiators 1020 and 1120. The plate thicknesses of the reflectors 1010, 1110 and the radiators 1020, 1120 are not limited, but are preferably about 0.5 mm, for example.

  Next, examples of specific shapes of the reflecting sections 1000 and 1100 will be described with reference to FIGS. 3 and 4.

  FIG. 3 is an explanatory diagram showing the structure of the reflection unit 1000. FIG. 3A is a perspective view showing a state in which the radiator 1020 is removed. FIG. 3B is a perspective view showing a state in which the reflector 1010 is removed. FIG. 3C is a perspective view showing a state in which the reflector 1010 and the radiator 1020 are overlapped with each other (a state in which the reflection section 1000 is configured).

  As shown in FIG. 3A, the radiator 1020 is provided at one end with a fixing portion 1021 for fixing to a frame 815 of the fixing device 8 described later with screws. The fixing portion 1021 is provided with a screw hole 1022 through which a screw 816 described later passes. Further, at the other end of the radiator 1020 (the end opposite to the fixed part 1021), engaging parts 1023, 1024 (parts having a convex plate surface) for engaging with a frame 815 of the fixing device 8 described later are provided. It is provided. The shape of the engaging portion of the reflecting portion 1000 (the reflector 1110 and the radiator 1020) is not particularly limited as long as it is a shape corresponding to the structure of the frame 815 of the fixing device 8. Further, as shown in FIG. 3B, the reflector 1010 is also provided at one end with a fixing portion 1011 for fixing to a frame 815 of the fixing device 8 described later with a screw 816 described later, and at the other end described later. Engaging portions 1013 and 1014 for engaging with the frame 815 of the fixing device 8 are provided. Further, the fixing portion 1011 is also provided with a screw hole 1012 for allowing a screw 816 described later to pass therethrough. Since the radiator 1020 and the reflector 1010 need to have a structure in which they are overlapped as shown in FIG. 3C, the shapes of the respective parts of the radiator 1020 and the reflector 1010 are formed so as to come into contact with each other when they are overlapped. Has been done.

  FIG. 4 is an explanatory diagram showing the structure of the reflecting section 1100. FIG. 4A is a perspective view showing a state in which the reflector 1110 is removed. FIG. 4B is a perspective view showing the radiator 1120 removed. FIG. 4C is a perspective view showing a state in which the reflector 1110 and the radiator 1120 are overlapped with each other (a state in which the reflection section 1100 is configured).

  As shown in FIG. 4A, the reflector 1110 is provided at one end with a fixing portion 1111 for fixing to a frame 815 of the fixing device 8 described later with a screw. The fixing portion 1111 is provided with a screw hole 1112 for allowing a screw 817 described later to pass therethrough. Further, the other end of the reflector 1110 (the end opposite to the fixing portion 1111) is provided with an engaging portion 1113 (a portion having a convex plate surface) for engaging with a frame 815 of the fixing device 8 described later. ing. The shape of the engaging portion of the reflecting portion 1100 (reflector 1110 and radiator 1120) is not particularly limited as long as it is a shape corresponding to the structure of the frame 815 of the fixing device 8. Further, as shown in FIG. 4B, the radiator 1120 is also provided at one end with a fixing portion 1121 for fixing to a frame 815 of the fixing device 8 described later with a screw 817 described later, and at the other end thereof is described later. An engaging portion 1123 for engaging with the frame 815 of the fixing device 8 is provided. Further, the fixing portion 1121 is also provided with a screw hole 1122 for allowing a screw 817 described later to pass therethrough. Since the reflector 1110 and the radiator 1120 need to have a configuration in which they are stacked as shown in FIG. 4C, the shapes of the respective portions of the reflector 1110 and the radiator 1120 are formed so as to come into contact with each other when they are stacked. Has been done.

  Further, as shown in FIG. 4A, the engaging portion 1113 of the reflector 1110 is provided with an engaging hole 1114 for engaging with the radiator 1120. Further, as shown in FIG. 4B, the radiator 1120 is provided with an engaging portion 1124 for inserting into the engaging hole 1114 of the reflector 1110 and engaging with the reflector 1110. The engagement portion 1124 has an inverted L-shape formed so as to project upward from the engagement portion 1123, and is inserted / engaged in the engagement hole 111 when the reflector 1110 and the radiator 1120 are overlapped with each other. The shape is compatible. That is, in the reflection portion 1100, the engagement portion 1124 is engaged with the engagement hole 1114 to facilitate keeping the reflector 1110 and the radiator 1120 in contact with each other (close contact).

  Next, a configuration for attaching the reflection units 1000 and 1100 to the fixing device 8 (frame 815) will be described with reference to FIGS.

  FIG. 5 is a perspective view of the fixing device 8 with the upper unit (Assy) 81 removed. The fixing device 8 also includes a lower unit (Assy) (not shown).

  As shown in FIG. 5, in the unit 81, each component is attached to a frame (housing) 815. Then, as shown in FIG. 5, the reflecting portions 1000 and 1100 are also attached to the frame 815.

  In FIG. 5, an arrow A1 indicates a side surface of the unit 81 (frame 815) on which the reflecting portions 1000 and 1100 are engaged. Further, in FIG. 6, an arrow A2 indicates the side surface of the frame 815 on which the reflecting portions 1000 and 1100 are screwed.

  FIG. 6A is a side view when the unit 81 (frame 815) is viewed from the direction of arrow A1. FIG. 6B is an enlarged view of a part of the unit 81 (frame 815) (a part surrounded by a dotted line in FIG. 6A). Further, FIG. 7 is a side view of the unit 81 (frame 815) viewed from the direction of arrow A2.

  FIG. 8 is an explanatory diagram (conceptual diagram) showing a configuration in which the reflecting section 1000 is attached to the frame 815. FIG. 9 is an explanatory diagram (conceptual diagram) showing a configuration in which the reflector 1100 is attached to the frame 815. 8 and 9 are views when the reflecting portions 1000 and 1100 are viewed from the longitudinal direction (the direction of arrow A3 in FIG. 5). 8 and 9 show the states (shapes) of the reflecting portions 1000 and 1100 at room temperature (when the halogen lamps 805 and 806 are off).

  As shown in FIGS. 7 and 8, the fixing portions 1011 and 1021 formed at one end of the reflecting portion 1000 are fixed to the supporting portion 815d of the frame 815 by screws 816. At that time, the screw 816 penetrates the screw holes 1012 and 1022 provided in the fixing portions 1011 and 1021.

  Then, as shown in FIGS. 6 and 8, the engaging portions 1013 and 1023 formed at the other end of the reflecting portion 1000 are in a state of being inserted into the mounting groove 815 a provided in the frame 815. That is, the engaging portions 1013 and 1023 are in a state of being supported by the mounting groove 815a. Further, the engaging portions 1014 and 1024 formed on the reflecting portion 1000 are also in a state of being inserted into the mounting groove 815b provided on the frame 815. That is, the engaging portions 1014 and 1024 are also supported by the mounting groove 815b.

  Although FIG. 8 shows the state where the engaging portions 1014 and 1024 penetrate the mounting groove 815b, the engaging portions 1013 and 1023 also penetrate the mounting groove 815b.

  As shown in FIGS. 7 and 9, the fixing portions 1111 and 1121 formed at one end of the reflecting portion 1100 are fixed to the supporting portion 815e of the frame 815 by screws 817. At that time, the screw 817 penetrates the screw holes 1112 and 1122 provided in the fixing portions 1111 and 1121.

  Then, as shown in FIGS. 6 and 9, the engaging portions 1113 and 1123 formed at the other end of the reflecting portion 1100 are in a state of being inserted into the mounting groove 815c provided in the frame 815. That is, the engaging portions 1113 and 1123 are in a state of being supported by the mounting groove 815c.

  As shown in FIGS. 6 and 8, in the reflecting portion 1000, the engaging portions 1013 and 1023 penetrate the mounting groove 815a, and the engaging portions 1014 and 1024 penetrate the mounting groove 815b.

  Then, as shown in FIG. 8, at normal temperature (when the halogen lamps 805 and 806 are OFF), the lengths of the engaging portions 1014 and 1024 in the longitudinal direction are inside the mounting groove 815b (inside the frame 815). It is assumed that the extra length portion 1000a for L1 is formed. In other words, the length L1 of the extra length portion 1000a is the width of the gap between the inner surface of the frame 815 and the main body portion of the reflecting section 1000. Although not shown in FIG. 8, it is assumed that the engaging portions 1013 and 1023 are also provided with the extra length portion 1000a corresponding to the length L1 in the longitudinal direction.

  FIG. 8 shows the state at normal temperature (when the halogen lamps 805 and 806 are off). However, when the halogen lamps 805 and 806 are turned on and the temperature of the reflection unit 1000 (reflector 1010, radiator 1020) rises, the reflection occurs. The part 1000 (reflector 1010, radiator 1020) expands, and the dimension in the longitudinal direction mainly extends. At this time, since one end of the reflection part 1000 (reflector 1010, radiator 1020) is only inserted into the mounting grooves 815a and 815b (the position in the longitudinal direction is not regulated), at least the extra length portion Even if the length L1 of 1000a is extended, it is possible to suppress the occurrence of bending or warping of the reflecting section 1000 (reflector 1010, radiator 1020). That is, the length L1 of the extra length portion 1000a at room temperature needs to be determined in consideration of the expansion coefficient of the reflecting portion 1000 (reflector 1010, radiator 1020) and the like. The reflector 1000 is made of materials having different heat characteristics (coefficient of thermal expansion, etc.), that is, the reflector 1010 and the radiator 1020. There is no.

  Further, as shown in FIG. 9, at the normal temperature (when the halogen lamps 805 and 806 are OFF), the engaging portion 1113, inside the mounting groove 815c (inside the frame 815), is also provided on the reflecting portion 1100 side. It is assumed that 1123 has an extra length portion 1100a corresponding to the length L2 in the longitudinal direction. The extra length portion 1100a fulfills the same function as the above-mentioned extra length portion 1000a (buffer function in consideration of thermal expansion of the reflection portion 1100). The length L2 may be the same as the length L1.

(A-2) Effects of the Embodiment According to this embodiment, the following effects can be achieved.

  In the fixing device 8 of this embodiment, radiators 1020 and 1120 for dissipating the heat of the reflectors 1010 and 1110 are provided in the reflecting portions 1000 and 1100. Thereby, the temperature rise of the reflectors 1010 and 1110 can be suppressed, and the deterioration of the reflection performance of the reflectors 1010 and 1110 can be suppressed.

  In addition, in the fixing device 8 of this embodiment, one end of each of the reflecting portions 1000 and 1100 is screwed and the other end is simply inserted into the mounting groove, and an extra length portion is provided in the engaging portion. As a result, in the fixing device 8, the occurrence of bending and warping due to thermal expansion of the reflecting portions 1000 and 1100 is suppressed.

  Furthermore, in this embodiment, in the reflecting portions 1000 and 1100, the contact surfaces of the reflectors 1010 and 1110 and the radiators 1020 and 1120 are attached without adhering. As a result, in the reflecting sections 1000 and 1100, deformation and bending due to the difference in expansion coefficient between the reflectors 1010 and 1110 and the radiators 1020 and 1120 are suppressed. Further, by attaching the contact surfaces of the reflectors 1010, 1110 and the radiators 1020, 1120 without adhering, a certain amount of clearance (play) is created between the reflectors 1010, 1110 and the radiators 1020, 1120, so that the reflector 1010, The deformation of 1110 and the radiators 1020, 1120 due to heat can be absorbed, and the change in shape of the reflecting sections 1000, 1100 as a whole can be suppressed.

(B) Other Embodiments The present invention is not limited to the above-described embodiments, but may include modified embodiments as exemplified below.

  (B-1) In the above embodiment, the image forming apparatus 100 has been described as an example in which the rolled continuous paper is applied as the medium, but the type of medium in the fixing device and the image forming apparatus of the present invention is described. (Material and shape) are not limited.

  Further, in the above embodiment, the image forming apparatus 100 is described as a color printer (a configuration including an image forming unit corresponding to a plurality of toner colors), but a monochrome printer (an image forming unit corresponding to only a single toner color is described. May be provided). Further, in the image forming apparatus 100, the method of transferring the toner image onto the paper P is not limited to the intermediate belt method, and various methods can be applied.

  Furthermore, in the above embodiment, an example in which the image forming apparatus and the fixing apparatus of the present invention are applied to a printer has been described, but the invention is applied to other image forming apparatuses (electrophotographic image forming apparatus) such as a FAX and a copying machine. You may do it.

  (B-2) In the fixing device 8 of the above embodiment, the halogen lamp 807 is also provided on the lower fixing belt 802, but the lower fixing belt 802 of the lower fixing belt 802 is omitted. Good.

  Further, in the fixing device 8 of the above-described embodiment, the radiator is not arranged in the reflecting portions 1200 and 1300 arranged on the lower fixing belt 802, but a radiator may be provided similarly to the reflecting portions 1000 and 1100. Good.

  (B-3) In the fixing device of the present invention, the number and shape of the heat radiating plates to be arranged are not limited.

100 ... Image forming device, 8 ... Fixing device, 81 ... Unit, 801, ... Fixing belt, 802 ... Fixing belt, 803 ... Roller drive, 804 ... Roller pressure, 805, 806, 807 ... Halogen lamp, 808, 809, 810, 811 ... Roller support, 812, 813, 814 ... Thermostat, 815 ... Frame, 815a, 815b, 815c ... Mounting groove, 815d, 815e ... Support portion, 816, 817 ... Screw, 1000 ... Reflecting portion, 1000a ... Extra length portion, 1010 ... Reflector, 1011 ... Fixing part, 1012 ... Screw hole, 1013 ... Engaging part, 1014 ... Engaging part, 1020 ... Radiator, 1021 ... Fixing part, 1022 ... Screw hole, 1023 ... Engaging part, 1024 ... Engaging Part, 1100 ... Reflecting part, 1100a ... Extra length part, 1110 ... Reflector, 111 ... Fixing part, 1112 ... Screw hole, 1113 ... Engaging part, 1114 ... Engaging hole, 1120 ... Radiator, 1121 ... Fixing part, 1122 ... Screw hole, 1123 ... Engaging part, 1124 ... Engaging part, 1200 ... Reflector, 1210 ... Reflector, 1300 ... Reflector, 1310 ... Reflector.

Claims (6)

A fixing belt,
A heat source for heating the fixing belt,
A reflector for reflecting heat from the heat source,
With a frame,
The reflector is
A reflecting member that reflects heat from the heat source,
A heat dissipating member that dissipates the heat of the reflecting member, the dissipating member being disposed on a surface opposite to the surface facing the heat source of the reflecting member,
The fixing device, wherein the frame is provided with a support portion that supports one end of the reflection portion in the longitudinal direction and a mounting groove that penetrates the other end of the reflection portion. A fixing belt,
A heat source for heating the fixing belt,
A reflector for reflecting heat from the heat source,
The reflector is
A reflecting member that reflects heat from the heat source,
A heat dissipating member that dissipates the heat of the reflecting member, the dissipating member being disposed on a surface opposite to the surface facing the heat source of the reflecting member,
The fixing device is characterized in that the heat dissipation member is formed of a material having a higher melting point than the reflection member.   The fixing device according to claim 1, wherein one end of the reflecting portion is fixed to the supporting portion.   The fixing portion according to claim 1, wherein an engaging portion for engaging with the frame is provided at one end of the reflecting portion in a longitudinal direction by penetrating the mounting groove. apparatus.   The fixing device according to claim 4, wherein the engaging portion is provided with an extra length portion having a predetermined length in a longitudinal direction inside the frame. An image forming apparatus comprising a fixing device for fixing a developer image formed on a medium, wherein the fixing device according to any one of claims 1 to 5 is applied as the fixing device.

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