Device including rotator and belt, such as a fixing unit for an image forming apparatus

Patent metadata

Field	Value
Publication number	US-10996600-B2
Application number	US-201916729785-A
Country	US
Kind code	B2
Filing date	Dec 30, 2019
Priority date	Mar 28, 2019
Publication date	May 4, 2021
Grant date	May 4, 2021

Abstract

A device includes a rotator having a rotation axis, a belt, a nip forming member surrounded by the belt, a first stay surrounded by the belt and extending in a width direction parallel to the rotation axis, a holder holding the nip forming member, and an urging member urging the first stay toward the rotator. The nip forming member is configured to, with the rotator, pinch the belt to form a nip. The first stay includes a first end and a second end. The holder includes a first engaging portion positioned at a first end of the holder, and a second engaging portion positioned at a second end of the holder. The first engaging portion engages the first end of the first stay. The second engaging portion engages the second end of the first stay.

First claim

What is claimed is:

1. A device, comprising:
a rotator having a rotation axis;
a belt;
a nip forming member surrounded by the belt, the nip forming member configured to, with the rotator, pinch the belt to form a nip;
a first stay surrounded by the belt and extending in a width direction parallel to the rotation axis, the first stay including a first end and a second end;
a holder holding the nip forming member and including:
a first engaging portion positioned at a first end of the holder, the first engaging portion including a first pair of pinching walls receiving the first end of the first stay therebetween, and a first connecting wall which connects the first pair of pinching walls and is located opposite to the rotator relative to the first end of the first stay received by the first pair of pinching walls, and
a second engaging portion positioned at a second end of the holder, the second engaging portion including a second pair of pinching walls receiving the second end of the first stay therebetween, and a second connecting wall which connects the second pair of pinching walls and is located opposite to the rotator relative to the second end of the first stay received by the second pair of pinching walls, and

an urging member urging the first stay toward the rotator.

2. The device according to claim 1 , wherein the first and second engaging portions are integrally formed with the holder.

3. The device according to claim 1 , wherein the pair of pinching walls face each other in a moving direction of the belt at the nip, the moving direction being perpendicular to the width direction.

4. The device according to claim 1 , further comprising a heater, wherein the rotator is arranged to be heated by the heater.

5. A device, comprising:
a rotator having a rotation axis;
a belt;
a nip forming member surrounded by the belt, the nip forming member configured to, with the rotator, pinch the belt to form a nip;
a first stay surrounded by the belt and extending in a width direction parallel to the rotation axis, the first stay including a first end and a second end;
a holder holding the nip forming member and including:
a first engaging portion positioned at a first end of the holder, the first engaging portion including a first pair of pinching walls receiving the first end of the first stay therebetween, and a first connecting wall which connects the first pair of pinching walls and is located opposite to the rotator relative to the first end of the first stay received by the first pair of pinching walls, and
a second engaging portion positioned at a second end of the holder, the second engaging portion including a second pair of pinching walls receiving the second end of the first stay therebetween, and a second connecting wall which connects the second pair of pinching walls and is located opposite to the rotator relative to the second end of the first stay received by the second pair of pinching walls,
a support surface which supports the nip forming member, and
a pair of side walls which sandwich the support surface therebetween in the width direction, and
wherein the first and second engaging portions each further include a reinforcing portion connecting the pinching walls and one of the side walls; and

an urging member urging the first stay toward the rotator.

6. The device according to claim 5 , wherein the reinforcing portions each define an opening configured to receive respective first and second buffers, wherein the first and second buffers engage the first and second ends, respectively, of the first stay.

7. The device according to claim 5 ,
wherein the holder includes a first extension wall extending from the support wall toward a side opposite to the nip forming member, and
wherein the first extension wall contacts to a downstream surface of the first stay which faces a downstream side in the moving direction.

8. The device according to claim 7 ,
wherein the holder includes a second extension wall extending from the support wall toward the side opposite to the nip forming member, and
wherein the second extension wall contacts to an upstream surface of the first stay which faces an upstream side in the moving direction.

9. The device according to claim 8 ,
wherein a distance from the center of the holder to the first extension wall or the second extension wall in the width direction is smaller than a distance from the first extension wall or the second extension wall to the engaging portion.

10. A device, comprising:
a rotator having a rotation axis;
a belt;
a nip forming member surrounded by the belt, the nip forming member configured to, with the rotator, pinch the belt to form a nip;
a first stay surrounded by the belt and extending in a width direction parallel to the rotation axis, the first stay including a first end and a second end;
a second stay positioned upstream of the first stay in a moving direction of the belt at the nip, the moving direction being perpendicular to the width direction;
a connector connecting the first stay and the second stay;
a holder holding the nip forming member and including:
a first engaging portion positioned at a first end of the holder, the first engaging portion engaging the first end of the first stay, and
a second engaging portion positioned at a second end of the holder, the second engaging portion engaging the second end of the first stay,
a holder body which holds the nip forming member and is positioned between the first and second engaging portions in the width direction, and

an urging member urging the first stay toward the rotator,
wherein the first stay includes:
a base portion which has a first end to contact the holder body and a second end being located opposite to the holder body relative to the first end; and
a bend portion which extends from the second end of the base portion toward the holder body, and

wherein the connector connects the first stay and the second stay at a position different from the bend portion in the width direction.

11. The device according to claim 10 ,
wherein the connector includes a crimped member crimped to the second stay and a screw with which the crimped member is fastened to the first stay.

12. The device according to claim 10 ,
wherein the second stay includes a plurality of protrusions to contact the holder and a plurality of holes which are located at positions different from the protrusions in the width direction.

13. A device, comprising:
a rotator having a rotation axis;
a belt;
a nip forming member surrounded by the belt, the nip forming member configured to, with the rotator, pinch the belt to form a nip;
a first stay surrounded by the belt and extending in a width direction parallel to the rotation axis, the first stay including a first end and a second end;
a holder holding the nip forming member and including:
a first engaging portion positioned at a first end of the holder, the first engaging portion engaging the first end of the first stay,
a second engaging portion positioned at a second end of the holder, the second engaging portion engaging the second end of the first stay,
a support wall which supports the nip forming member, and
a plurality of ribs which protrude from the support wall to contact the first stay,
wherein the plurality of ribs extend in a moving direction of the belt at the nip, the moving direction being perpendicular to the width direction, and are spaced from one another in the width direction, and

an urging member urging the first stay toward the rotator.

14. The device according to claim 13 , further comprising a downstr

Assignees

• Brother Ind Ltd

Inventors

• Handa Hiroshi
• Watanabe Tomonori
• Fukue Shuhei
• Takeuchi Kenji
• Taguchi Kazuna
• Ogasawara Tatsuo

Classifications

• G03G15/757

  Drive mechanisms for photosensitive medium, e.g. gears · CPC title

• G03G15/2053 Primary

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

• G03G21/1685

  for the fixing unit · CPC title

• G03G2215/2009

  Pressure belt · CPC title

• G03G15/206 Primary

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