Developing device

• US 9,405,229 B1
• Filed: 01/21/2016
• Issued: 08/02/2016
• Est. Priority Date: 01/22/2015
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Nose, Katsuya, Saito, Fumiyoshi, Yago, Toshihisa, Mugita, Naoki, Ishida, Yusuke, Takeuchi, Kosuke
• Primary Examiner(s): Bolduc, David
• Assistant Examiner(s): FEKETE, BARNABAS T
• Application Number:
  US15/002,910
• Publication Number:
  US 20160216640A1
• Time in Patent Office: 194 Days
• Field of Search: 399/254, 399/258
• US Class Current: 1/1
• CPC Class Codes: G03G 15/0891 for conveying or circulating developer, e.g. augers
• CPC Class Codes: G03G 15/0893 in a closed loop within the sump of the developing device

Abstract

A developing device includes a developer carrying member, a first chamber, a second chamber, a first feeding member, and a second feeding member. The second feeding member includes first to third spiral portions and a disk portion. The disk portion includes a projected portion. When the disk portion is seen in an axial direction of the second feeding member, on the basis of a line connecting a rotation center of the disk portion and an upstream end portion of the third spiral portion with respect to a feeding direction of the third spiral portion, the projected portion is provided within a range from a position deviated by 90 degrees toward a downstream side with respect to a rotational direction of the disk portion to a position deviated by 30 degrees toward an upstream side with respect to the rotational direction of the disk portion.

Claims

1. A developing device comprising:

a developer carrying member for carrying and feeding a developer;

a first chamber for supplying the developer to said developer carrying member;

a second chamber for forming a circulation path of the developer in communication with said first chamber and for delivering the developer between itself and said first chamber;

a first feeding member, provided rotatably in said first chamber, for feeding the developer in said first chamber; and

a second feeding member, provided rotatably in said second chamber, for feeding the developer in said second chamber, wherein said second feeding member comprises,

a first spiral portion including a first spiral feeding blade for feeding the developer in said second chamber in a feeding direction opposite to a feeding direction in said first chamber,

a second spiral portion including a second spiral feeding blade for feeding a part of the developer fed by said first spiral portion in a feeding direction opposite to the feeding direction of said first spiral portion,

a third spiral portion including a third spiral feeding blade for feeding the developer fed by getting over said second spiral portion in the same feeding direction as the feeding direction of said first spiral portion, and

a disk portion provided between said second spiral portion and said third spiral portion,

wherein said disk portion includes a projected portion projected from a part of an outer peripheral surface of said disk portion in a radial direction, and

wherein when said disk portion is seen in an axial direction of said second feeding member, on the basis of a line connecting a rotation center of said disk portion and an upstream end portion of said third spiral portion with respect to the feeding direction of said third spiral portion, said projected portion is provided within a range from a position deviated by 90 degrees toward a downstream side with respect to a rotational direction of said disk portion to a position deviated by 30 degrees toward an upstream side with respect to the rotational direction of said disk portion.

2. A developing device according to claim 1, wherein said projected portion is provided within a range from a position deviated by 30 degrees toward the downstream side with respect to the rotational direction of said disk portion to a position deviated by 10 degrees toward the upstream side with respect to the rotational direction of said disk portion.

3. A developing device according to claim 1, wherein said projected portion is provided within a range from a position deviated by 5 degrees toward the downstream side with respect to the rotational direction of said disk portion to a position deviated by 5 degrees toward the upstream side with respect to the rotational direction of said disk portion.

4. A developing device according to claim 1, wherein said projected portion is provided on an extension line of a line connecting the rotation center of said disk portion and a connecting end portion of said third spiral feeding blade.

5. A developing device according to claim 1, wherein said second feeding member rotates so that a peripheral speed of said disk portion is 80 mm/s or more and 600 mm/s or less.

6. A developing device according to claim 1, wherein said second chamber is formed so that a cross-sectional area thereof on a downstream side with respect to the feeding direction of said third spiral portion is smaller than a cross-sectional area thereof on an upstream side with respect to the feeding direction of said third spiral portion.

7. A developing device according to claim 1, wherein said second chamber includes a discharge opening for permitting discharge of the developer on a downstream side with respect to the feeding direction of said third spiral portion.