Developing apparatus having a layer thickness regulation member, cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-9946189-B2
Application number	US-201615366206-A
Country	US
Kind code	B2
Filing date	Dec 1, 2016
Priority date	Feb 18, 2014
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

A developing apparatus includes a developer bearing member configured to bear a developer on a surface, a regulating member that regulates layer thickness of the developer on the developer bearing member, and a developer conveying member. In addition, a frame has a development chamber in which the developer bearing member and the regulating member are provided, a storage chamber in which the conveying member is provided and the developer is stored, and an opening through which the developer passes into the development chamber. The developing apparatus collects the developer remaining on the developer bearing member into the storage chamber after the developer on the developer bearing member is transferred onto a transfer material. The regulating material includes a step portion that forms a gap between the regulating member and the developer bearing member.

First claim

What is claimed is:

1. A developing apparatus comprising:
a developer bearing member configured to bear a developer on a surface;
a regulating member configured to regulate a layer thickness of the developer borne on the surface of the developer bearing member;
a conveying member configured to convey the developer; and
a frame having a development chamber in which the developer bearing member and the regulating member are provided, a storage chamber in which the conveying member is provided and the developer is stored, and an opening through which the developer being conveyed by the conveying member from the storage chamber passes into the development chamber,
the developing apparatus collecting the developer remaining on an image bearing member into the storage chamber, after the developer on the image bearing member is transferred onto a transfer material,
wherein, in a cross section perpendicular to the longitudinal direction of the developer bearing member, a cross sectional area of the storage chamber is larger than that of the development chamber,
wherein, when a developing operation is performed, a contact region between the developer bearing member and the regulating member is located directly above the opening in a vertical direction and the developer scraped off from a surface of the developer bearing member at the contact region falls into the storage chamber, and
wherein the regulating member includes a protruded portion protruding to the developer bearing member side between a distal end portion and an opposite end portion of the regulating member, the protruded portion being in contact with the developer bearing member such that a first gap is formed between a first part of the regulating member, which is closer to the distal end portion than the protruded portion, and the developer bearing member, and a second gap is formed between a second part of the regulating member, which is closer to the opposite end portion than the protruded portion, and the developer bearing member.

2. The developing apparatus according to claim 1 , wherein, when the developing operation is performed, a bottom section of the development chamber is located above a bottom section of the storage chamber in a vertical direction.

3. The developing apparatus according to claim 1 , wherein the developer is a one component developer.

4. The developing apparatus according to claim 1 , wherein the developing apparatus collects the developer remaining on the image bearing member into the storage chamber as a cleaner-less system.

5. The developing apparatus according to claim 1 , wherein the regulating member includes a step portion with the first gap, and a corner portion of the step portion comes in contact with the developer bearing member.

6. The developing apparatus according to claim 1 , wherein
the regulating member includes a supporting section and a conductive member that covers the supporting section, and
the conductive member comes in contact with the developer bearing member.

7. The developing apparatus according to claim 1 , wherein an axial center of the developer bearing member, which is rotatably provided, is located above an axial center of the conveying member, which is rotatably provided, in the vertical direction.

8. The developing apparatus according to claim 1 , wherein the contact region is located above an axial center of the conveying member, which is rotatably provided, in the vertical direction.

9. The developing apparatus according to claim 1 , wherein a rotating direction of the developer bearing member is a direction from a lower end portion to an upper end portion of the opening in a portion where the developer bearing member opposes the opening.

10. The developing apparatus according to claim 1 , wherein average circularity of the developer is equal to or higher than 0.93.

11. The developing apparatus according to claim 1 , wherein a degree of agglomeration of the developer is equal to or lower than 55.

12. The developing apparatus according to claim 1 , wherein the developer is a magnetic developer.

13. A cartridge detachably provided in a main body of an image forming apparatus that performs image formation, the cartridge comprising:
the developing apparatus according to claim 1 ; and
an image bearing member to which the developer is supplied by the developer bearing member to develop an electrostatic latent image formed on a surface of the image bearing member into a developer image.

14. An image forming apparatus that performs image formation, comprising:
the developing apparatus according to claim 1 ; and
an image bearing member to which the developer is supplied by the developer bearing member to develop an electrostatic latent image formed on a surface of the image bearing member into a developer image.

15. The image forming apparatus according to claim 14 , further comprising a transfer member provided in contact with the image bearing member and configured to transfer the developer image onto a transfer material.

16. The developing apparatus according to claim 1 , wherein the frame comprises a first frame body and a second frame body, wherein the first frame body constitutes a part of the development chamber and includes the opening.

17. The developing apparatus according to claim 1 , wherein the frame comprises a first frame body and a second frame body, wherein the first frame body constitutes a part of the development chamber and includes the opening, and the second frame body constitutes a part of the storage chamber.

18. The developing apparatus according to claim 1 , wherein the frame comprises a first frame body and a second frame body, wherein the first frame body constitutes a part of the development chamber and includes the opening, and when viewed in a rotation axis direction of the developer bearing member, a line drawn downward in the gravity direction from the contact region crosses the second frame body.

19. The developing apparatus according to claim 5 , wherein the regulating member includes the protruded portion having a curved surface, as the step portion.

Assignees

• Canon Kk

Inventors

• Adachi Motoki
• Ito Motonari
• Watanabe Takanori
• Usui Yusuke

Classifications

• G03G21/10 Primary

  Collecting or recycling waste developer · CPC title

• G03G15/0812 Primary

  characterised by the developer regulating means, e.g. structure of doctor blade · CPC title

• G03G15/0851

  the concentration being measured by electrical means · CPC title

• G03G15/082

  for immersion · CPC title

• G03G21/0064

  using the developing unit, e.g. cleanerless or multi-cycle apparatus · CPC title