Developer container, developing apparatus, process cartridge, apparatus main body, and image forming apparatus

• US 9,857,730 B2
• Filed: 01/27/2016
• Issued: 01/02/2018
• Est. Priority Date: 01/30/2015
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kato, Masahito, Shibukawa, Kenta, Yamauchi, Kazumi, Abe, Katsuichi, Asanuma, Naoya, Toda, Atsushi, Kishi, Yosuke, Fukushima, Naoki
• Primary Examiner(s): WALSH, RYAN D
• Application Number:
  US15/007,265
• Publication Number:
  US 20160223950A1
• Time in Patent Office: 706 Days
• CPC Class Codes: G03G 15/0856 Detection or control means for the developer level
• CPC Class Codes: G03G 15/086 the level being measured by electro-magnetic means
• CPC Class Codes: G03G 15/0889 for agitation or stirring
• CPC Class Codes: G03G 2215/085 Stirring member in developer container
• CPC Class Codes: G03G 2215/0888 Arrangements for detecting toner level or concentration in the developing device

Abstract

A developer container includes: a housing chamber 147 which includes an opening 145 and which houses developer; a stirring member 160 which includes a sheet-like stirring portion 160b and a rotary shaft 160a to which the stirring portion 160b is attached; and a first electrode 143 and a second electrode 144 which are used to detect an amount of the developer and which are arranged with an interval therebetween, where in an area X1 between the first electrode 143 and the second electrode 144 in the housing chamber 147 is positioned below the rotary shaft 160a of the stirring member 160, and the sheet-like stirring portion 160b comes into contact with the area X1 due to rotation of the stirring member 160.

Claims

1. A developing apparatus comprising:

a developer bearing member for bearing developer;

a frame housing the developer;

a stirring member including a sheet-like stirring portion and a rotary shaft to which the sheet-like stirring portion is attached; and

a first electrode and a second electrode which are used to detect an amount of the developer and which are arranged with an interval therebetween,

wherein an area between the first electrode and the second electrode in a surface of the frame is positioned below the rotary shaft of the stirring member and below a lower end of the developer bearing member, and

wherein the sheet-like stirring portion comes into contact with the first electrode, with the second electrode, and with the area due to rotation of the stirring member.

2. The developing apparatus according to claim 1, wherein the first electrode and the second electrode are positioned below the rotary shaft of the stirring member.

3. The developing apparatus according to claim 1, wherein the area is an area including a lowermost position in the frame.

4. The developing apparatus according to claim 1, wherein the first electrode, the second electrode, and the area are arranged in an order of the second electrode, the area, and the first electrode in a rotational direction of the stirring member below a center of the rotary shaft.

5. The developing apparatus according to claim 1, wherein the first electrode and the second electrode are sheet-like conductive members installed along a wall surface of the frame.

6. The developing apparatus according to claim 1,

wherein the frame is divided into a first housing area and a second housing area from a side of an opening of the frame toward a distal side,

wherein the stirring member is a first stirring member that is rotatably provided in the first housing area,

wherein the developing apparatus further comprises a second stirring member that is rotatably provided in the second housing area,

wherein the first electrode and the second electrode are arranged in the first housing area, and

wherein the developing apparatus further comprises a third electrode and a fourth electrode which are used to detect an amount of the developer and which are arranged with an interval therebetween in the second housing area.

7. The developing apparatus according to claim 6, wherein the second electrode and the third electrode are a single electrode member arranged so as to straddle the first housing area and the second housing area.

8. The developing apparatus according to claim 6,

wherein the first electrode is positioned below a rotary shaft of the first stirring member, and

wherein the fourth electrode is positioned below a rotary shaft of the second stirring member.

9. The developing apparatus according to claim 6,

wherein the area is a first area in the first housing area, and

wherein the second stirring member comes into contact with a second area between the third electrode and the fourth electrode in the second housing area due to rotation.

10. The developing apparatus according to claim 6, wherein the first housing area and the second housing area are divided by a convex portion that protrudes upward in a vertical direction on a wall surface forming the frame.

11. The developing apparatus according to claim 1,

wherein the frame includes an opening, and

wherein a lower end of the opening is positioned above the rotary shaft.

12. The developing apparatus according to claim 1, further comprising:

a detecting portion for detecting an amount of the developer; and

a contact portion which is capable of coming into contact with the rotating stirring member so as push off developer on the stirring member such that the developer drops at a faster rate than when the developer drops from the stirring member by its own weight.

13. The developing apparatus according to claim 1,

wherein a difference between an initial value that is a value of capacitance between the first electrode and the second electrode immediately after start of a new image forming process using the developing apparatus and a value of the capacitance at a predetermined timing is acquired,

wherein a remaining amount of developer in the frame is acquired based on the difference, and

wherein the initial value is a value of the capacitance acquired after the developer in the frame is stirred by the stirring member.

14. The developing apparatus according to claim 13, wherein the initial value is a maximum value of the capacitance in a case where the capacitance increases after a temporary decrease.

15. The developing apparatus according to claim 13, wherein the initial value is an average value of maximum values of the capacitance while the stirring member makes one round immediately after the start of the new image forming process.

16. The developing apparatus according to claim 13, wherein the initial value is a value of the capacitance after a developer bearing member that bears developer for developing an electrostatic latent image and the stirring member are driven for a predetermined period of time and is a maximum value of the capacitance while the stirring member makes one round.

17. A process cartridge that can be detachable from an apparatus main body of an image forming apparatus, the process cartridge comprising:

the developing apparatus according to claim 1; and

an image bearing member that bears an electrostatic image to be developed by developer.

18. An image forming apparatus which forms an image on a recording material using developer,

wherein the developing apparatus according to claim 1 is configured to be detachable from a main body of the image forming apparatus.

19. The developing apparatus according to claim 1, wherein the first and second electrodes are used to detect the amount of the developer by using a capacitance between the first electrode and the second electrode.