Heating device, fixing device, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-12197151-B2
Application number	US-202318225158-A
Country	US
Kind code	B2
Filing date	Jul 24, 2023
Priority date	Aug 1, 2022
Publication date	Jan 14, 2025
Grant date	Jan 14, 2025

Abstract

A heating device includes a rotator, a heater, a rotator holder, lubricant, and a shield. The heater heats the rotator in a heat generation range. The rotator holder holds an end of the rotator in a longitudinal direction of the rotator. The lubricant adheres to the rotator holder. The shield shields heat transferred from the heater. The shield includes a first shield, a second shield, and a heat transfer reducer. The first shield faces the heater and the rotator. The second shield faces the rotator holder. The second shield is outside the heat generation range in the longitudinal direction. The heat transfer reducer is disposed between the first shield and the second shield. The heat transfer reducer reduces the heat transferred from the first shield to the second shield.

First claim

The invention claimed is:

1. A heating device comprising:
a rotator;
a heater to heat the rotator in a heat generation range;
a rotator holder holding an end of the rotator in a longitudinal direction of the rotator;
lubricant adhering to the rotator holder; and
a shield to shield heat transferred from the heater, the shield including:
a first shield facing the heater and the rotator;
a second shield facing the rotator holder, the second shield being outside the heat generation range in the longitudinal direction; and
a heat transfer reducer between the first shield and the second shield, the heat transfer reducer configured to reduce the heat transferred from the first shield to the second shield,

wherein:
the heat transfer reducer has a gap between the first shield and the second shield,
the first shield is separated from the second shield,
the first shield is separated from the second shield in the longitudinal direction with the gap, and
the first shield is closer to the heater than the second shield in a direction orthogonal to the longitudinal direction.

2. The heating device according to claim 1 ,
wherein the heat transfer reducer includes a thermal insulator having a thermal conductivity lower than a thermal conductivity of the first shield.

3. The heating device according to claim 1 ,
wherein the second shield is closer to the heater than the first shield in the direction orthogonal to the longitudinal direction.

4. The heating device according to claim 1 , further comprising:
another first shield disposed between the first shield and the rotator in the direction orthogonal to the longitudinal direction.

5. The heating device according to claim 1 , further comprising;
another second shield between the second shield and the rotator holder in the direction orthogonal to the longitudinal direction.

6. The heating device according to claim 1 ,
wherein an end part of the first shield is overlapped with an end part of the second shield in the direction orthogonal to the longitudinal direction.

7. The heating device according to claim 1 ,
wherein the heat transfer reducer has:
a connecting portion connecting the first shield to the second shield in the longitudinal direction; and
a slit at a position corresponding to the connection portion in the longitudinal direction to divide the shield into the first shield and the second shield.

8. A fixing device comprising:
the heating device according to claim 1 .

9. An image forming apparatus comprising:
the fixing device according to claim 8 .

10. A heating device, comprising:
a rotator;
a heater to heat the rotator in a heat generation range;
a rotator holder holding an end of the rotator in a longitudinal direction of the rotator;
lubricant adhering to the rotator holder;
a shield to shield heat transferred from the heater, the shield including:
a first shield facing the heater and the rotator;
a second shield facing the rotator holder, the second shield being outside the heat generation range in the longitudinal direction; and

a heat transfer reducer between the first shield and the second shield, the heat transfer reducer configured to reduce the heat transferred from the first shield to the second shield; and
another first shield disposed between the first shield and the rotator in a direction orthogonal to the longitudinal direction,
wherein said another first shield is thinner than the first shield.

11. The heating device according to claim 10 ,
wherein the heat transfer reducer includes a thermal insulator having a thermal conductivity lower than a thermal conductivity of the first shield.

12. The heating device according to claim 10 ,
wherein the heat transfer reducer has:
a connecting portion connecting the first shield to the second shield in the longitudinal direction; and
a slit at a position corresponding to the connection portion in the longitudinal direction to divide the shield into the first shield and the second shield.

13. A fixing device comprising:
the heating device according to claim 10 .

14. An image forming apparatus comprising:
the fixing device according to claim 13 .

15. A heating device comprising:
a rotator:
a heater to heat the rotator in a heat generation range:
a rotator holder holding an end of the rotator in a longitudinal direction of the rotator;
lubricant adhering to the rotator holder:
a shield to shield heat transferred from the heater, the shield including:
a first shield facing the heater and the rotator;
a second shield facing the rotator holder, the second shield being outside the heat generation range in the longitudinal direction; and

a heat transfer reducer between the first shield and the second shield, the heat transfer reducer configured to reduce the heat transferred from the first shield to the second shield; and
another second shield between the second shield and the rotator holder in a direction orthogonal to the longitudinal direction,
wherein said another second shield is thinner than the second shield.

16. The heating device according to claim 15 ,
wherein the heat transfer reducer includes a thermal insulator having a thermal conductivity lower than a thermal conductivity of the first shield.

17. The heating device according to claim 15 ,
wherein the heat transfer reducer has:
a connecting portion connecting the first shield to the second shield in the longitudinal direction; and
a slit at a position corresponding to the connection portion in the longitudinal direction to divide the shield into the first shield and the second shield.

18. A fixing device comprising:
the heating device according to claim 15 .

19. An image forming apparatus comprising:
the fixing device according to claim 18 .

Assignees

• Samei Masahiro
• Andoh Takayuki
• Shiodera Kota
• Yoshinaga Hiroshi
• Kabata Toshiyuki
• Ricoh Co Ltd

Inventors

• Samei Masahiro
• Andoh Takayuki
• Shiodera Kota
• Yoshinaga Hiroshi
• Kabata Toshiyuki

Classifications

• G03G2215/2035

  the fixing nip having a stationary belt support member opposing a pressure member · 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

• G03G15/2017 Primary

  Structural details of the fixing unit in general, e.g. cooling means, heat shielding means (G03G15/2053 takes precedence) · CPC title