Image forming device

Abstract

A photosensitive drum 18 is provided to carry electrostatic latent images. Developers 23K through 23Y supply toner to the electrostatic latent images formed on the photosensitive drum 18. Images formed on the photosensitive drum 18 are transferred to an intermediate transfer belt 12. A primary transfer roller 16 transfers toner images formed on the photosensitive drum 18 onto the intermediate transfer belt 12. The secondary transfer roller 7 transfers toner images on the intermediate transfer belt 12 onto sheets. The belt cleaning unit 17 has a fur brush 32 that electrically recovers toner, and recovers residual transfer toner remaining on the intermediate transfer belt 12 after a secondary transfer by the secondary transfer roller 7. The drive roller 13 is disposed in a position in opposition to the fur brush 32 sandwiching the intermediate transfer belt 12, and charges both the fur brush 32 and the secondary transfer roller 7.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

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

FIG. 1 is a cross-sectional diagrammatical view showing a schematic configuration of an image forming device according to the present invention;

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

FIG. 3 is a view of a diagram showing the relationship between each cleaning bias and the TD (transmission density) values in the present invention;

FIG. 4 is a view of a diagram showing the relationship between each cleaning bias and the TD values in a comparison example; and

FIG. 5 is a view of Table 1 showing intermediate transfer belt surface resistivity, brush fiber volume resistance, transfer efficiency, transfer performance evaluation, cleaning bias possible setting range, cleaning performance evaluation, and overall evaluation, for the present invention and comparison examples.

Claims

1. An image forming device, comprising: an image carrier being configured to carry electrostatic latent images;a developer being configured to provide toner to electrostatic latent images formed on the image carrier;an intermediate transfer belt, toner images formed on the image carrier being configured to be transferred to the intermediate transfer belt;a primary transfer member being configured to transfer toner images formed on the image carrier to the intermediate transfer belt;a secondary transfer member being configured to transfer toner images on the intermediate transfer belt to sheets;a belt cleaning unit having a fur brush being configured to recover electrically toner, the belt cleaning unit being configured to recover transfer toner remaining on the intermediate transfer belt after a secondary transfer by the secondary transfer member; andan opposing electrode being disposed in a position in opposition to both the fur brush and the secondary transfer member to sandwich the intermediate transfer belt.

2. The image forming device according to claim 1, wherein the belt cleaning unit is configured to be separable from the intermediate transfer belt.

3. The image forming device according to claim 1, wherein the fur brush has brush fibers formed from an electrically conducting material, the intermediate transfer belt is formed from an electrically conducting material whose surface resistivity is within the range 5.1×108 through 1.0×1010 Ω/□, and the volume resistance of the brush fibers is within the range 3.2×105 through 2.1×107Ω.

4. The image forming device according to claim 2, wherein the fur brush has brush fibers formed from an electrically conducting material, the intermediate transfer belt is formed from an electrically conducting material whose surface resistivity is within the range 5.1×108 through 1.0×1010 Ω/□, and the volume resistance of the brush fibers is within the range 3.2×105 through 2.1×107Ω.

5. The image forming device according to claim 1, wherein the opposing electrode is a grounded roller member whose surface is formed from an electrically conducting elastic member disposed in opposition to the fur brush.

6. The image forming device according to claim 2, wherein the opposing electrode is a grounded roller member whose surface is formed from an electrically conducting elastic member disposed in opposition to the fur brush.

7. The image forming device according to claim 3, wherein the opposing electrode is a grounded roller member whose surface is formed from an electrically conducting elastic member disposed in opposition to the fur brush.

8. The image forming device according to claim 4, wherein the opposing electrode is a grounded roller member whose surface is formed from an electrically conducting elastic member disposed in opposition to the fur brush.

9. The image forming device according to claim 1, wherein the cleaning unit further comprises a housing, at least a portion of the housing being formed from an electrically conducting material to which a bias is applied, and a recovery roller formed from an electrically conducting material and supported by the housing.

10. The image forming device according to claim 2, wherein the cleaning unit further comprises a housing, at least a portion of the housing being formed from an electrically conducting material to which a bias is applied, and a recovery roller formed from an electrically conducting material and supported by the housing.

11. The image forming device according to claim 3, wherein the cleaning unit further comprises a housing, at least a portion of the housing being formed from an electrically conducting material to which a bias is applied, and a recovery roller formed from an electrically conducting material and supported by the housing.

12. The image forming device according to claim 4, wherein the cleaning unit further comprises a housing, at least a portion of the housing being formed from an electrically conducting material to which a bias is applied, and a recovery roller formed from an electrically conducting material and supported by the housing.

13. The image forming device according to claim 5, wherein the cleaning unit further comprises a housing, at least a portion of the housing being formed from an electrically conducting material to which a bias is applied, and a recovery roller formed from an electrically conducting material and supported by the housing.

14. The image forming device according to claim 8, wherein the cleaning unit further comprises a housing, at least a portion of the housing being formed from an electrically conducting material to which a bias is applied, and a recovery roller formed from an electrically conducting material and supported by the housing.

15. The image forming device according to claim 9, wherein the distance from the center of the rotation axis of the fur brush to the intermediate transfer belt is greater than the distance from the center of the rotation axis of the fur brush to the surface of the recovery roller.

16. The image forming device according to claim 10, wherein the distance from the center of the rotation axis of the fur brush to the intermediate transfer belt is greater than the distance from the center of the rotation axis of the fur brush to the surface of the recovery roller.

17. The image forming device according to claim 11, wherein the distance from the center of the rotation axis of the fur brush to the intermediate transfer belt is greater than the distance from the center of the rotation axis of the fur brush to the surface of the recovery roller.

18. The image forming device according to claim 12, wherein the distance from the center of the rotation axis of the fur brush to the intermediate transfer belt is greater than the distance from the center of the rotation axis of the fur brush to the surface of the recovery roller.

19. The image forming device according to claim 13, wherein the distance from the center of the rotation axis of the fur brush to the intermediate transfer belt is greater than the distance from the center of the rotation axis of the fur brush to the surface of the recovery roller.

20. The image forming device according to claim 14, wherein the distance from the center of the rotation axis of the fur brush to the intermediate transfer belt is greater than the distance from the center of the rotation axis of the fur brush to the surface of the recovery roller.