Process cartridge, electrophotographic image forming apparatus, and electrophotographic photosensitive drum unit

• US 8,682,215 B1
• Filed: 12/10/2013
• Issued: 03/25/2014
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ueno, Takahito, Miyabe, Shigeo, Morioka, Masanari, Hisano, Masato
• Primary Examiner(s): Gaworecki, Mark R
• Application Number:
  US14/101,724
• Publication Number:
  US 20140099144A1
• Time in Patent Office: 105 Days
• Field of Search: 399/110, 399/111, 399/167
• US Class Current: 399/111
• CPC Class Codes: G03G 15/751 relating to drum G03G15/757 takes precedence
• CPC Class Codes: G03G 15/757 Drive mechanisms for photosensitive medium, e.g. gears
• CPC Class Codes: G03G 21/1647 Mechanical connection means
• CPC Class Codes: G03G 21/1814 Details of parts of process cartridge, e.g. for charging, transfer, cleaning, developing G03G21/1835 takes precedence
• CPC Class Codes: G03G 21/1817 having a submodular arrangement
• 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 21/1842 for guiding and mounting the process cartridge, positioning, alignment, locks G03G21/1864 and G03G21/1871 take precedence
• CPC Class Codes: G03G 21/185 the process cartridge being mounted parallel to the axis of the photosensitive member
• CPC Class Codes: G03G 21/1853 the process cartridge being mounted perpendicular to the axis of the photosensitive member
• CPC Class Codes: G03G 21/1857 for transmitting mechanical drive power to the process cartridge, drive mechanisms, gears, couplings, braking mechanisms
• CPC Class Codes: G03G 21/186 Axial couplings
• CPC Class Codes: G03G 2221/1657 transmitting mechanical drive power

Abstract

A process cartridge includes a casing, a photosensitive drum having an axis L1, the photosensitive drum being rotatably supported in the casing to permit rotation about the axis L1, and a coupling member having an axis L2, with the coupling member including (i) a first end portion connected to the photosensitive drum, (ii) a second end portion, and (iii) a connecting portion connecting the first end portion and the second end portion. The second end portion includes at least one pair of projections, with each of the projections including a facing portion that faces the axis L2, each facing portion being open to the axis L2. A diameter of an imaginary circle that is tangent to the facing portions of the projections is greater than a maximum dimension of the connecting portion in a direction perpendicular to the axis L2.

Claims

1. A process cartridge comprising:

a casing;

a photosensitive drum having an axis L1, the photosensitive drum being rotatably supported in the casing to permit rotation about the axis L1; and

a coupling member having an axis L2, the coupling member including (i) a first end portion connected to the photosensitive drum, (ii) a second end portion, and (iii) a connecting portion connecting the first end portion and the second end portion,

wherein the second end portion includes at least one pair of projections, with each of the projections including a facing portion that faces the axis L2, each facing portion being open to the axis L2,

wherein a diameter of an imaginary circle that is tangent to the facing portions of the projections is greater than a maximum dimension of the connecting portion in a direction perpendicular to the axis L2, and

wherein the coupling member is movable between a first position in which the axis L2 of the coupling member is coaxial with the axis L1 of the photosensitive drum, and a second position in which the axis L2 of the coupling member is inclined with respect to the axis L1 of the photosensitive drum.

2. A process cartridge according to claim 1, wherein in the second position, the coupling member is fully inclined with respect to the axis L1 of the photosensitive drum, and an angle of inclination of the axis L2 with respect to the axis L1 is about 20 degrees to about 60 degrees.

3. A process cartridge according to claim 2, wherein the first end portion of the coupling member has a maximum outer dimension in a direction perpendicular to the axis L2 that is greater than the maximum outer dimension of the connecting portion of the coupling member.

4. A process cartridge according to claim 2, wherein at least the second end portion of the coupling member is outside of the casing.

5. A process cartridge according to claim 1, wherein a maximum distance from the axis L2 to an outermost surface of the connecting portion along a line perpendicular to the axis L2 is less than a maximum distance from the axis L2 to an outermost surface of the second end portion along a line perpendicular to the axis L2.

6. A process cartridge according to claim 5, wherein the connecting portion comprises a shaft along the axis L2.

7. A process cartridge according to claim 1, wherein, for at least part of the second end portion, a maximum distance from the axis L2 to the outermost surface along a line perpendicular to the axis L2 increases as the distance along the axis L2 from the connecting portion increases.

8. A process cartridge according to claim 1, wherein the second end portion comprises an opening to a recess, with the opening facing away from the connecting portion.

9. A process cartridge according to claim 1, wherein the coupling member is connected to the photosensitive drum by a flange.

10. A process cartridge according to claim 9, wherein the flange has a hollow portion, and at least part of the first end portion of the coupling member is in the hollow portion of the flange.

11. A process cartridge according to claim 1, wherein the coupling member is connected to a shaft that is connected to the photosensitive drum.

12. A process cartridge according to claim 11, wherein the shaft is connected to the photosensitive drum by a flange.

13. A process cartridge according to claim 1, wherein the casing comprises a guide portion capable of guiding the coupling member toward the second position, wherein the guide portion projects substantially in the same direction as the axis L1 and is disposed in proximity to the coupling member.

14. A drum unit usable in a process cartridge, the drum unit comprising:

a photosensitive drum having an axis L1;

a flange provided at one end of the photosensitive drum that is coaxial with the axis L1; and

a coupling member having an axis L2, the coupling member including (i) a first end portion connected to the flange, (ii) a second end portion, and (iii) a connecting portion connecting the first end portion and the second end portion,

wherein the second end portion includes at least one pair of projections, with each of the projections including a facing portion that faces the axis L2, each facing portion being open to the axis L2,

wherein a diameter of an imaginary circle that is tangent to the facing portions of the projections is greater than a maximum dimension of the connecting portion in a direction perpendicular to the axis L2, and

wherein the coupling member is movable between a first position in which the axis L2 of the coupling member is coaxial with the axis L1 of the photosensitive drum, and a second position in which the axis L2 of the coupling member is inclined with respect to the axis L1 of the photosensitive drum.

15. A drum unit according to claim 14, wherein in the second position, the coupling member is fully inclined with respect to the axis L1 of the photosensitive drum, and an angle of inclination of the axis L2 with respect to the axis L1 is about 20 degrees to about 60 degrees.

16. A drum unit according to claim 14, wherein a maximum distance from the axis L2 to an outermost surface of the connecting portion along a line perpendicular to the axis L2 is less than a maximum distance from the axis L2 to an outermost surface of the second end portion along a line perpendicular to the axis L2.

17. A drum unit according to claim 16, wherein the connecting portion comprises a shaft along the axis L2.

18. A drum unit according to claim 14, wherein, for at least part of the second end portion, a maximum distance from the axis L2 to the outermost surface along a line perpendicular to the axis L2 increases as the distance along the axis L2 from the connecting portion increases.

19. A drum unit according to claim 14, wherein the second end portion comprises an opening to a recess, with the opening facing away from the connecting portion.

20. A drum unit according to claim 14, wherein the flange has a hollow portion, and at least part of the first end portion of the coupling member is in the hollow portion of the flange.

21. A drum unit according to claim 14, wherein the coupling member is connected to a shaft that is connected to the flange.

22. A drum unit according to claim 14, wherein the first end portion of the coupling member has a maximum outer dimension in a direction perpendicular to the axis L2 that is greater than the maximum outer dimension of the connecting portion of the coupling member.

23. A process cartridge comprising:

a casing;

a photosensitive drum having an axis L1, the photosensitive drum being rotatably supported in the casing to permit rotation about the axis L1;

a developer roller having an axis L2, the developer roller being rotatably supported in the casing to permit rotation about the axis L2; and

a coupling member having an axis L3, the coupling member having (i) a first end portion connected to the photosensitive drum, (ii) a second end portion, and (iii) a connecting portion connecting the first end portion and the second end portion,

wherein the coupling member is movable between a first position in which the axis L3 of the coupling member is coaxial with the axis L1 of the photosensitive drum, and a second position in which the axis L3 of the coupling member is fully inclined with respect to the axis L1 of the photosensitive drum and in which a portion of the axis L3 at the first end portion side of the coupling member is nearer to the axis L2 of the developer roller than a portion of the axis L3 at the second end portion side of the coupling member, and

wherein when the coupling member is in the second position, the axis L3 of the coupling member is inclined from about 20 degrees to about 60 degrees with respect to the axis L1 of the photosensitive drum.

24. A process cartridge according to claim 23, wherein a maximum distance from the axis L3 to an outermost surface of the connecting portion along a line perpendicular to the axis L3 is less than a maximum distance from the axis L3 to an outermost surface of the second end portion along a line perpendicular to the axis L3.

25. A process cartridge according to claim 23, wherein the connecting portion comprises a shaft along the axis L3.

26. A process cartridge according to claim 23, wherein the second end portion includes at least one projection and an opening to a recess, with the opening facing away from the connecting portion.

27. A process cartridge according to claim 23, wherein the coupling member is connected to the photosensitive drum by a flange.

28. A process cartridge according to claim 27, wherein the flange has a hollow portion, and at least part of the first end portion of the coupling member is in the hollow portion of the flange.

29. A process cartridge according to claim 23, wherein at least the second end portion of the coupling member is outside of the casing.

30. An image forming apparatus comprising:

a process cartridge including;

a casing;

a photosensitive drum having an axis L1, the photosensitive drum being rotatably supported in the casing to permit rotation about the axis L1; and

a coupling member having an axis L2, the coupling member including (i) a first end portion connected to the photosensitive drum, (ii) a second end portion, and (iii) a connecting portion connecting the first end portion and the second end portion,

wherein the second end portion includes at least one pair of projections, with each of the projections including a facing portion that faces the axis L2, each facing portion being open to the axis L2,

wherein a diameter of an imaginary circle that is tangent to the facing portions of the projections is greater than a maximum dimension of the connecting portion in a direction perpendicular to the axis L2, and

wherein the coupling member is movable between a first position in which the axis L2 of the coupling member is coaxial with the axis L1 of the photosensitive drum, and a second position in which the axis L2 of the coupling member is inclined with respect to the axis L1 of the photosensitive drum;

a driving motor;

a driving shaft engageable with the second end portion of the coupling member of the process cartridge and having a rotational axis L3;

a guide portion configured to guide insertion of the process cartridge into the image forming apparatus along a direction that is substantially perpendicular to the rotational axis L3 of the driving shaft; and

an urging member movable between an urging position and a retracted position retracted from the urging position,

wherein, when the process cartridge is mounted to the image forming apparatus, the coupling member is inclined toward the driving shaft by being urged by an elastic force of the urging member restoring to the urging position after being temporarily retracted to the retracted position by being contacted by the coupling member.