Developer conveyance device and image forming apparatus incorporating same

Patent metadata

Field	Value
Publication number	US-10935907-B2
Application number	US-202016876134-A
Country	US
Kind code	B2
Filing date	May 18, 2020
Priority date	Jun 6, 2019
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A developer conveyance device includes a downward conveyance path in which a developer falls under gravity, a transverse conveyance path communicating with a lower end of the downward conveyance path and extending in a transverse direction intersecting with the downward conveyance path, a transport screw disposed in the transverse conveyance path, and a floating member. The transport screw is configured to rotate in a predetermined direction to transport the developer in the transverse direction. The floating member is configured to contact the transport screw rotating in the predetermined direction to float in the downward conveyance path.

First claim

What is claimed is:

1. A developer conveyance device comprising:
a downward conveyance path in which a developer falls under gravity;
a transverse conveyance path communicating with a lower end of the downward conveyance path and extending in a transverse direction intersecting with the downward conveyance path;
a transport screw disposed in the transverse conveyance path and configured to rotate in a predetermined direction to transport the developer in the transverse direction; and
a floating member configured to contact the transport screw rotating in the predetermined direction to float in the downward conveyance path,
wherein the floating member has a columnar shape.

2. The developer conveyance device according to claim 1 ,
wherein the floating member is softer than the transport screw.

3. The developer conveyance device according to claim 1 ,
wherein the floating member is softer than an inner wall of the downward conveyance path.

4. The developer conveyance device according to claim 1 ,
wherein the floating member is elastic.

5. The developer conveyance device according to claim 1 ,
wherein the floating member has a hollow tubular shape.

6. The developer conveyance device according to claim 1 ,
wherein the developer conveyance device satisfies a relation R>M−N,
where R represents a diameter of an inscribed circle of a bottom face of the floating member, M represents a screw pitch of the transport screw, and N represents a thickness of a thread of the transport screw.

7. The developer conveyance device according to claim 1 ,
wherein the developer conveyance device satisfies a relation H>D,
where H represents a length of the floating member, and D represents an inner diameter of a cross-section of the downward conveyance path.

8. The developer conveyance device according to claim 1 ,
wherein a specific gravity of the floating member is greater than a specific gravity of the developer.

9. The developer conveyance device according to claim 1 ,
wherein the developer is excess toner.

10. An image forming apparatus comprising the developer conveyance device according to claim 1 .

11. The developer conveyance device according to claim 1 , wherein:
the columnar shape of the floating member is cylindrical.

12. A developer conveyance device comprising:
a downward conveyance path in which a developer falls under gravity;
a transverse conveyance path communicating with a lower end of the downward conveyance path and extending in a transverse direction intersecting with the downward conveyance path;
a transport screw disposed in the transverse conveyance path and configured to rotate in a predetermined direction to transport the developer in the transverse direction; and
a structure within the downward conveyance path, the structure floating in the downward conveyance path and having a columnar shape.

13. The developer conveyance device according to claim 12 ,
wherein the structure within the downward conveyance path is softer than the transport screw.

14. The developer conveyance device according to claim 12 ,
wherein the structure within the downward conveyance path is softer than an inner wall of the downward conveyance path.

15. The developer conveyance device according to claim 12 ,
wherein the structure within the downward conveyance path is elastic.

16. The developer conveyance device according to claim 12 ,
wherein the structure within the downward conveyance path has a hollow tubular shape.

17. The developer conveyance device according to claim 12 ,
wherein the developer conveyance device satisfies a relation R>M−N,
where R represents a diameter of an inscribed circle of a bottom face of the structure within the downward conveyance path, M represents a screw pitch of the transport screw, and N represents a thickness of a thread of the transport screw.

18. The developer conveyance device according to claim 12 ,
wherein the developer conveyance device satisfies a relation H>D,
where H represents a length of the structure within the downward conveyance path, and D represents an inner diameter of a cross-section of the downward conveyance path.

19. The developer conveyance device according to claim 12 ,
wherein a specific gravity of the structure within the downward conveyance path is greater than a specific gravity of the developer.

20. The developer conveyance device according to claim 12 , wherein:
the columnar shape of the structure within the downward conveyance path is cylindrical.

Assignees

• Ishizuka Yusuke
• Fujimori Akira
• Kimura Hideki
• Takahashi Yutaka
• Kikuchi Hiroshi
• Uenishi Hiroyuki
• Yahagi Johji
• Ricoh Co Ltd

Inventors

• Ishizuka Yusuke
• Fujimori Akira
• Kimura Hideki
• Takahashi Yutaka
• Kikuchi Hiroshi
• Uenishi Hiroyuki
• Yahagi Johji

Classifications

• G03G15/0891 Primary

  for conveying or circulating developer, e.g. augers · CPC title

• G03G15/095

  Removing excess solid developer {, e.g. fog preventing} · CPC title

• G03G21/105 Primary

  Arrangements for conveying toner waste · CPC title