Fixing device and image forming apparatus incorporating same

Patent metadata

Field	Value
Publication number	US-10955780-B2
Application number	US-202016897343-A
Country	US
Kind code	B2
Filing date	Jun 10, 2020
Priority date	Jul 10, 2019
Publication date	Mar 23, 2021
Grant date	Mar 23, 2021

Abstract

A fixing device includes a fixing rotator, a pressure rotator configured to press the fixing rotator, a fixing structure, a temperature detector, a discharger, and a holder. The fixing structure is configured to hold at least one of the fixing rotator and the pressure rotator. The temperature detector is configured to contact a detected member that is at least one of the fixing rotator and the pressure rotator and detect a temperature of the detected member. The discharger is configured to contact and discharge the detected member. The holder is fixed on the fixing structure and configured to hold the temperature detector and the discharger.

First claim

What is claimed is:

1. A fixing device comprising:
a fixing rotator;
a pressure rotator configured to press the fixing rotator;
a fixing structure configured to hold at least one of the fixing rotator and the pressure rotator;
a temperature detector configured to contact a detected member that is at least one of the fixing rotator and the pressure rotator and detect a temperature of the detected member;
a discharger configured to contact and discharge the detected member; and
a holder fixed on the fixing structure and configured to hold the temperature detector and the discharger.

2. The fixing device according to claim 1 , further comprising:
a plurality of regulators configured to restrict a movement of the holder in a direction away from the detected member,
wherein the holder includes a support configured to hold the discharger and the temperature detector and disposed on a line connecting two regulators of the plurality of regulators or inside a polygonal shape formed by connecting three or more regulators of the plurality of regulators.

3. The fixing device according to claim 2 ,
wherein the detected member has a cylindrical shape, and
the plurality of regulators is configured to restrict a movement of the holder in a tangential direction at a contact position between the detected member and the temperature detector.

4. The fixing device according to claim 2 ,
wherein the plurality of regulators includes:
at least one screw configured to screw the holder to the fixing structure; and
a step screw configured to screw the holder to the fixing structure.

5. The fixing device according to claim 2 ,
wherein at least one of the plurality of regulators includes:
an insertion projection disposed on one of the holder and the fixing structure and projecting in a direction orthogonal to a direction away from the detected member; and
an insertion hole disposed on the other one of the holder and the fixing structure to insert the insertion projection.

6. The fixing device according to claim 2 ,
wherein at least one of the plurality of regulators includes a contact surface of the fixing structure that the holder is configured to contact in a direction away from the detected member.

7. The fixing device according to claim 1 ,
wherein the fixing structure is made of metal, and
the holder includes:
a base made of insulating resin and fixed on the fixing structure; and
a resistor held by the holder and configured to electrically couple the fixing structure to the discharger, the resistor having an electrical resistance larger than an electrical resistance of the fixing structure and smaller than an electrical resistance of the base.

8. The fixing device according to claim 7 , further comprising
a plurality of regulators configured to restrict a movement of the holder in a tangential direction at a contact position between the detected member and the temperature detector,
wherein the detected member has a cylindrical shape.

9. The fixing device according to claim 7 , further comprising a plurality of regulators that includes:
at least one screw configured to screw the holder to the fixing structure; and
a step screw configured to screw the holder to the fixing structure.

10. The fixing device according to claim 7 , further comprising a plurality of regulators that includes at least one regulator including:
an insertion projection disposed on one of the holder and the fixing structure and projecting in a direction orthogonal to a direction away from the detected member and
an insertion hole disposed on the other one of the holder and the fixing structure to insert the insertion projection.

11. The fixing device according to claim 7 , further comprising a plurality of regulators that includes at least one regulator including a contact surface of the fixing structure that the holder is configured to contact in a direction away from the detected member.

12. The fixing device according to claim 1 ,
wherein the holder includes a positioning portion configured to position the holder on the fixing structure.

13. An image forming apparatus comprising:
an image forming device configured to form an image on a recording medium; and
the fixing device according to claim 1 configured to fix the image on the recording medium.

Assignees

• Seshita Takuya
• Kajiyama Hiroshi
• Fujiwara Hitoshi
• Ricoh Co Ltd

Inventors

• Seshita Takuya
• Kajiyama Hiroshi
• Fujiwara Hitoshi

Classifications

• G03G15/2028

  with means for handling the copy material in the fixing nip, e.g. introduction guides, stripping means · CPC title

• G03G15/2064

  combined with pressure · CPC title

• G03G15/2053

  Structural details of heat elements, e.g. structure of roller or belt, eddy current, induction heating · CPC title

• G03G15/206

  Structural details or chemical composition of the pressure elements and layers thereof · CPC title

• G03G15/2039 Primary

  with means for controlling the fixing temperature · CPC title