FIXING DEVICE

Abstract

A fixing device 100 includes a fixing belt 102, a heat source 105, a support member 104, a pressure roller 103, and a reinforcing member 106. The fixing belt 102 has a metal sleeve. The heat source 105 is provided within the fixing belt 102. The support member 104 has a contact surface 104a that is in sliding contact with the inside surface of the fixing belt 102. The pressure roller 103 forms a nip with the bottom surface 104a between which the fixing belt 102 is sandwiched and pressed. The pressure roller 103 drives the fixing belt 102 to rotate. The reinforcing member 106 has a surface contacting the support member 104 on which a plurality of irregularities is formed. The reinforcing member 106 is positioned on a side opposite the support member to the bottom surface 104a, and receives a pressure force applied by the pressure roller 103.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the attached drawings which form a part of this original disclosure:

FIG. 1 is a schematic cross-sectional view showing the outline of an image forming device according to a first preferred embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view showing the configuration of a fixing device of the image forming device;

FIG. 3 is an isometric view of a support member and a reinforcing member of the fixing device;

FIG. 4 is an alternate isometric view of the reinforcing member;

FIG. 5 is an isometric view of a modified reinforcing member;

FIG. 6 is an enlarged view of a modified fixing device corresponding to FIG. 2;

FIG. 7 is a schematic cross-sectional view of a conventional fixing device used for comparison;

FIG. 8 is a schematic cross-sectional view of a fixing device used in accordance with the first embodiment for comparison;

FIG. 9 is a view of a graph showing temperature measurement results;

FIG. 10 is a schematic cross-sectional view showing the configuration of a fixing device according to a second preferred embodiment of the present invention;

FIG. 11 is a view of a graph showing temperature measurement results;

FIG. 12 is a view of an outline diagram showing an example of a fixing device according to a third preferred embodiment of the present invention;

FIG. 13 is a view of a diagram showing the variation in nip pressure in a lengthwise direction according to whether there is a reinforcing member or not;

FIGS. 14A and 14B are isometric views showing an example of installation of the reinforcing member on the support member;

FIG. 15 is an isometric view showing another example of installation of the reinforcing member on the support member; and

FIG. 16 is a cross-sectional view showing an example of the film used in the present invention.

Claims

1. A fixing device, comprising: an endless loop shaped heating member;a heating source being disposed within said heating member;a support member having a contact surface being configured to contact an inside surface of said heating member;a pressure member being configured to contact a part of said heating member corresponding to a part being configured to contact said contact surface of said support member; anda reinforcing member being configured to reinforce said support member.

2. The fixing device according to claim 1, wherein said support member and said reinforcing member are integrally formed.

3. The fixing device according to claim 1, wherein the thickness of said reinforcing member is thicker than the thickness of said support member.

4. The fixing device according to claim 1, wherein a base material of said heating member is a metal sleeve, said pressure member forms a nip with said contact surface of said support member between which said heating member is sandwiched and pressed and said pressure member drives said heating member to rotate in a predetermined direction, said reinforcing member has a contact surface that contacts said support member on which a plurality of irregularities is formed, that receives a pressure force of said pressure member applied to said support member in a position on a side opposite to said contact surface of said support member.

5. The fixing device according to claim 4, wherein a plurality of spherical-shaped projections is formed on said contact surface of said reinforcing member.

6. The fixing device according to claim 4, wherein a plurality of rib-shaped projections extending in the rotation direction of said heating member is formed on said contact surface of said reinforcing member.

7. The fixing device according to claim 1, further comprising thermal insulation material arranged between said support member and said reinforcing member.

8. The fixing device according to claim 7, wherein said thermal insulation material is a heat resistant resin or silicone rubber.

9. The fixing device according to claim 1, wherein said reinforcing member comprises a plate shaped member that contacts a surface of said support member opposite said contact surface of said support member, and a plate shaped rib disposed on a upper surface of said plate shaped member opposite said support member in approximately the center of said plate shaped member in the width direction and at right angles to said plate shaped member.

10. The fixing device according to claim 4, wherein said reinforcing member has a plate shaped member that contacts a surface of said support member opposite said contact surface of said support member, and a plate shaped rib disposed on a upper surface of said plate shaped member opposite said support member in approximately the center of said plate shaped member in the width direction and at right angles to said plate shaped member.

11. The fixing device according to claim 7, wherein said reinforcing member has a plate shaped member that contacts a surface of said support member opposite said contact surface of said support member , and a plate shaped rib disposed on the upper surface of said plate shaped member opposite said support member in approximately the center of said plate shaped member in the width direction and at right angles to said plate shaped member.

12. The fixing device according to claim 1, wherein a base material of said heating member is a metal sleeve, said pressure member forms a nip with said contact surface of said support member between which said heating member is sandwiched and pressed, and said pressure member drives said heating member to rotate in a predetermined direction, said reinforcing member contacts the support member on a side opposite said support member to said heating member and receives a pressure force from said pressure member applied to said support member, and at least one of said support member and said reinforcing member is formed either in whole or in part from a thermal insulation material.

13. The fixing device according to claim 12, wherein said reinforcing member has a plate shaped member that contacts a surface of said support member opposite said contact surface of said support member, and a plate shaped rib disposed on the upper surface of said plate shaped member opposite said support member in approximately the center of the plate shaped member in the width direction and at right angles to said plate shaped member.

14. The fixing device according to claim 12, wherein the thermal insulation material includes one of poly-etheretherketone (PEEK), polyimide (PI), polyamideimide (PAI), polybenzimidazole (PBI), polytetrafluoroethylene (PTFE), or perfluoro alkoxyl alkane (PFA).

15. The fixing device according to claim 1, wherein said heating member is a cylindrical shaped film that can freely rotate, said heat source is provided within said film and radiates radiant heat, said support member has a contact surface that contacts an inner peripheral surface of said film, said pressure member presses against said contact surface of said support member via said film, and said reinforcing member is a plate shaped member that is installed on a surface of said support member opposite said contact surface in the length direction and substantially perpendicular to said support member.

16. The fixing device according to claim 15, wherein said support member supports said reinforcing member by support portions formed by cutting out and bending parts of said support member to form cutout parts and said support portions.

17. The fixing device according to claim 16, wherein each cutout part has one support portion.

18. The fixing device according to claim 17, wherein said support portions are arranged on alternate sides of said cutout parts.

19. The fixing device according to claim 16, wherein each cutout part has two support portions.