Development device, process cartridge, and image forming apparatus

• US 10,254,710 B2
• Filed: 11/14/2017
• Issued: 04/09/2019
• Est. Priority Date: 11/18/2016
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Nosho, Hiroaki, Oguma, Toru, Numata, Tetsuya
• Primary Examiner(s): Curran, Gregory H
• Application Number:
  US15/812,977
• Publication Number:
  US 20180143584A1
• Time in Patent Office: 511 Days
• CPC Class Codes: G03G 15/086 the level being measured by electro-magnetic means
• CPC Class Codes: G03G 21/1652 Electrical connection means
• CPC Class Codes: G03G 21/1676 for the developer unit
• CPC Class Codes: G03G 21/1821 means for connecting the different parts of the process cartridge, e.g. attachment, positioning of parts with each other, pressure/distance regulation G03G21/1825 takes precedence
• CPC Class Codes: G03G 21/1871 associated with a positioning function

Abstract

There are demands for stable connections of contact points between a process cartridge, including a development device, and an image forming device. A development contact point, a first contact point, and a second contact point are disposed in this order on the inside in a perpendicular direction with respect to an insertion direction in which a development device is inserted into an image forming apparatus.

Claims

1. A development device which is removably insertable into an image forming apparatus, the development device comprising:

a housing configured to store developer;

a developer carrying member configured to carry developer;

a first conductive member having a first surface for use in detection of an amount of developer stored in the housing based on a change in electrostatic capacitance, the first conductive member extending in a longitudinal direction of the developer carrying member, the longitudinal direction being perpendicular to an insertion direction in which the development device is inserted into the image forming apparatus;

a second conductive member having a second surface facing the first surface, the second conductive member extending in the longitudinal direction of the developer carrying member;

a development contact point electrically connected to the developer carrying member;

a first contact point electrically connected to the first conductive member; and

a second contact point electrically connected to the second conductive member,

wherein the first contact point is disposed on a more inner side than the development contact point in a perpendicular direction with respect to the insertion direction, and

wherein the second contact point is disposed on a more inner side than the first contact point in the perpendicular direction with respect to the insertion direction.

2. The development device according to claim 1, wherein the first conductive member and the second conductive member are conductive resin members containing a resin.

3. The development device according to claim 1, wherein the first conductive member is disposed closer to the developer carrying member than the second conductive member is to the developer carrying member.

4. The development device according to claim 1, wherein the housing includes a bearing member configured to support the developer carrying member,

wherein a portion of the bearing member is electrically connected to the developer carrying member,

wherein the portion of the bearing member is a conductive resin member, and

wherein the conductive resin member is electrically connected to the development contact point.

5. The development device according to claim 1, further comprising a conveyance member configured to convey the developer,

wherein the conveyance member includes a shaft portion and a sheet-shaped conveyance portion, and

wherein when viewed from the longitudinal direction of the developer carrying member, the shaft portion is located immediately above a position between the first conductive member and the second conductive member.

6. The development device according to claim 1, further comprising a third conductive member having a third surface and extending in the longitudinal direction of the developer carrying member.

7. A process cartridge comprising:

an image carrying member; and

the development device according to claim 1.

8. An image forming apparatus comprising:

the development device according to claim 1; and

a voltage application unit configured to apply an alternating current (AC) voltage to the second contact point of the development device.

9. An image forming apparatus comprising:

the development device according to claim 1;

a movable member which is movable into the image forming apparatus in the insertion direction of the development device;

a first main body contact point which is electrically connectable to the first contact point of the development device; and

a second main body contact point which is electrically connectable to the second contact point of the development device.

10. An image forming apparatus comprising:

the development device according to claim 1; and

a detection unit electrically connectable to the first contact point of the development device and configured to detect a change in voltage or current.

11. The development device according to claim 1, wherein the housing includes a bottom member that supports the developer from below when the development device is inserted into the image forming apparatus, and

wherein the first conductive member and the second conductive member are disposed along an inner surface of the bottom member, the inner surface is an inner surface of the housing.

12. The development device according to claim 1, wherein the bottom member has a curved shape.