DEVELOPING APPARATUS

• US 20150016837A1
• Filed: 07/10/2014
• Published: 01/15/2015
• Est. Priority Date: 07/10/2013
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Kitajima, Tomoharu
• Granted Patent: US 9,383,685 B2
• Time in Patent Office: Days
• US Class Current: 399/104
• CPC Class Codes: G03G 15/0817 characterised by the lateral sealing at both sides of the donor member with respect to the developer carrying direction
• CPC Class Codes: G03G 15/0942 with means for preventing toner scattering from the magnetic brush, e.g. magnetic seals

Abstract

A developing apparatus includes a developing container for accommodating a developer including magnetic particles; a developer feeding member, provided in the developing container and having a magnetic shaft, for feeding the developer; a bearing rotatably supporting the shaft; a bearing accommodating portion; and a magnet, provided around the shaft at a position inside the bearing in the bearing accommodating portion, for forming a magnetic seal of magnetic particles by a magnetic field formed between itself and the shaft; wherein the bearing accommodating portion includes a first space between the magnet and the bearing and a second space which is provided outside of the bearing with respect to a diametrical direction and which is in fluid communication with the first space to receive the developer from the first space.

Claims

1. A developing apparatus comprising:

a developing container for accommodating a developer including magnetic particles;

a developer feeding member, provided in said developing container and having a magnetic shaft, for feeding the developer by rotation of the shaft;

a bearing rotatably supporting said shaft;

a bearing accommodating portion for accommodating said bearing; and

a magnet, provided around said shaft at a position inside said bearing in said bearing accommodating portion, for forming a magnetic seal of magnetic particles by a magnetic field formed between itself and said shaft;

wherein said bearing accommodating portion includes a first space between said magnet and said bearing and a second space which is provided outside of said bearing with respect to a diametrical direction and which is in fluid communication with said first space to receive the developer from said first space.

2. An apparatus according to claim 1, wherein said second space is disposed below said first space in use.

5. An apparatus according to claim 1, wherein said second space is closed and stores the developer received from said first space.

6. An apparatus according to claim 1, further comprising a developer collecting means, connected with said second space, for collecting the developer received from said first space.

7. An apparatus according to claim 6, wherein said collecting means is disposed below said second space in use and includes a collection feeding portion for feeding the developer into a collection container, and a communicating portion for fluid communication between said second space and said collection feeding portion.

8. An apparatus according to claim 7, wherein said collection feeding portion collects the developer overflowed from said developing container and feeds the overflowed developer into said collection container.

9. An apparatus according to claim 1, wherein said second space is in a region of said developing container projected in an axial direction.

10. An apparatus according to claim 1, wherein said bearing accommodating portion including a support cylindrical portion which engages with said bearing and said magnet to support them and which is provided with a cut-away portion in fluid communication with said second space, and said cut-away portion has a width measured in a circumferential direction of said bearing smaller than a diameter of an outer peripheral surface of said bearing.

3. A developing apparatus comprising:

a developing container for accommodating a developer including magnetic particles, said developer container including a first chamber and a second chamber;

a first developer feeding member, provided in said first chamber and having a first magnetic shaft, for feeding the developer by rotation of the first shaft;

a first bearing rotatably supporting said first shaft in said first chamber;

a first bearing accommodating portion for accommodating said first bearing;

a first magnet, provided around said first shaft at a position inside said first bearing in said first bearing accommodating portion, for forming a first magnetic seal of magnetic particles by a magnetic field formed between itself and said first shaft,

wherein said first bearing accommodating portion includes a first space between said first magnet and said first bearing and a second space which is provided outside of said first bearing with respect to a diametrical direction and which is in fluid communication with said first space to receive the developer from said first space;

a second developer feeding member, provided in said second chamber and having a second magnetic shaft, for feeding the developer by rotation of the second shaft;

a second bearing rotatably supporting said second shaft in said second chamber;

a second bearing accommodating portion for accommodating said second bearing; and

a second magnet, provided around said second shaft at a position inside said second bearing in said second bearing accommodating portion, for forming a second magnetic seal of magnetic particles by a magnetic field formed between itself and said second shaft, wherein said second bearing accommodating portion includes a third space between said second magnet and said second bearing.

4. An apparatus according to claim 3, wherein said second chamber is disposed below said first chamber in use, wherein said first developer feeding member feeds the developer toward one axial end portion in said first chamber, and said second developer feeding member feeds the developer toward the other axial end portion in said second chamber to push the developer up into said first chamber through a communication port, and wherein said first and second bearing accommodating portions are provided at the other axial end portions, and said second space is provided at least in said first bearing accommodating portion.