Rotational Force Transmitting Parts

• US 20080260428A1
• Filed: 12/26/2007
• Published: 10/23/2008
• 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, Morioka, Masanari, Miyabe, Shigeo, Hisano, Masato
• Granted Patent: US 8,295,734 B2
• Time in Patent Office: Days
• US Class Current: 399/167
• 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 21/1853 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 rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein the electrophotographic photosensitive drum is dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, the rotating force transmitting part includes a coupling member engageable with the rotational force applying portion to receive a rotational force for rotating the electrophotographic photosensitive drum in the state in which electrophotographic photosensitive drum is mounted to the main assembly of the electrophotographic image forming apparatus, wherein the coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating the electrophotographic photosensitive drum to the electrophotographic photosensitive drum and a disengaging angular position in which the coupling member is inclined away from the axis of the electrophotographic photosensitive drum from the rotational force transmitting angular position, wherein when the process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a direction substantially perpendicular to the axis of the electrophotographic photosensitive drum, the coupling member moves from the rotational force transmitting angular position to the disengaging angular position.

Claims

1. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member engageable with said rotational force applying portion to receive a rotational force for rotating said electrophotographic photosensitive drum in the state in which electrophotographic photosensitive drum is mounted to said main assembly of the electrophotographic image forming apparatus, wherein said coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum to said electrophotographic photosensitive drum and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position,

wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a direction substantially perpendicular to the axis of said electrophotographic photosensitive drum, said coupling member moves from said rotational force transmitting angular position to said disengaging angular position.

2. A rotating force transmitting part according to claim 1, wherein said coupling member has a recess in which a rotational axis of said coupling member extends, and said recess is over a free end of said driving shaft in the state in which said coupling member is positioned at said rotational force transmitting angular position, wherein said coupling member is rotated by a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft, wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member pivots from said rotational force transmitting angular position to said disengaging angular position so that a part of said coupling member circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

3. A rotating force transmitting part according to claim 1 or 2, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other.

4. A rotating force transmitting part according to claim 2, wherein said recess includes an expanding portion expanding toward a free end thereof, and wherein a plurality of said rotational force receiving portions are provided at regular intervals along a rotational direction of said coupling member, wherein the rotational force applying portion is provided at each of two positions which are diametrically opposite to each other with respect to the axis of the driving shaft, and

wherein said coupling member receives a rotational force from the driving shaft to rotate by one of said rotational force receiving portions engaging to one of the rotational force applying portion and by the other of rotational force receiving portions engaging to the other of the rotational force applying portions, said one of said rotational force receiving portions being opposed to the other of said rotational force receiving portions, and said one of said rotational force applying portions being opposed to the other of said rotational force applying portions.

5. A rotating force transmitting part according to claim 4, wherein said expanding portion has a conical shape having an apex on the rotational axis of said coupling member, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the apex is opposed to the free end of the driving shaft, and said coupling member is over the free end of the driving shaft when the rotational force is transmitted to said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

6. A rotating force transmitting part according to claim 1, 2, 4 or 5, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

53. A rotating force transmitting part according to claim 1, 7, 13, 19, 22, 31, 40 or 49, wherein said coupling member is provided to an end of said electrophotographic photosensitive drum and is capable of tilting relative to the axis of said electrophotographic photosensitive drum substantially in all directions.

7. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member engageable with said rotational force applying portion to receive a rotational force for rotating said electrophotographic photosensitive drum, said coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum to said electrophotographic photosensitive drum and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position,

wherein in the state in which said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, a part of said coupling member is behind the driving shaft as seen in a direction opposite a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the driving shaft by said coupling member moving from the rotational force transmitting angular position to the disengaging angular position so as to permit the part of the coupling member to circumvent the driving shaft.

8. A rotating force transmitting part according to claim 7, wherein said coupling member has a recess in which a rotational axis of said coupling member extends, and said recess is over a free end of said driving shaft in the state in which said coupling member is positioned at said rotational force transmitting angular position, wherein said coupling member is rotated by a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft.

9. A rotating force transmitting part according to claim 8, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other.

10. A rotating force transmitting part according to claim 8, wherein said recess includes an expanding portion expanding toward a free end thereof, and wherein a plurality of said rotational force receiving portions are provided at regular intervals along a rotational direction of said coupling member, wherein the rotational force applying portion is provided at each of two positions which are diametrically opposite to each other with respect to the axis of the driving shaft, and

wherein said coupling member receives a rotational force from the driving shaft to rotate by one of said rotational force receiving portions engaging to one of the rotational force applying portion and by the other of rotational force receiving portions engaging to the other of the rotational force applying portions, said one of said rotational force receiving portions being opposed to the other of said rotational force receiving portions, and said one of said rotational force applying portions being opposed to the other of said rotational force applying portions.

11. A rotating force transmitting part according to claim 10, wherein said expanding portion has a conical shape having an apex on the rotational axis of said coupling member, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the apex is opposed to the free end of the driving shaft, and said coupling member is over the free end of the driving shaft when the rotational force is transmitted to said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

12. A rotating force transmitting part according to claim 10 or 11, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

13. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member for transmitting a rotational force to said electrophotographic photosensitive drum, said coupling member including rotational force receiving portion for engaging with the rotational force applying portion to receive a rotational force from the driving shaft, and a rotational force transmitting portion for transmitting the rotational force received through said rotational force receiving portion to said electrophotographic photosensitive drum, said coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum to said electrophotographic photosensitive drum and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position;

a rotating force receiving member for receiving the rotating force from said rotating force transmitting portion to rotate said electrophotographic photosensitive drum;

wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the driving shaft by moving from said rotational force transmitting angular position to said disengaging angular position in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

14. A rotating force transmitting part according to claim 13, wherein said coupling member has a recess in which a rotational axis of said coupling member extends, and said recess is over a free end of said driving shaft in the state in which said coupling member is positioned at said rotational force transmitting angular position, wherein said coupling member receives a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft, wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member pivots from said rotational force transmitting angular position to said disengaging angular position so that a part of said coupling member circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

15. A rotating force transmitting part according to claim 13 or 15, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other.

16. A rotating force transmitting part according to claim 14, wherein said recess includes an expanding portion expanding toward a free end thereof, and wherein a plurality of said rotational force receiving portions are provided at regular intervals along a rotational direction of said coupling member, wherein the rotational force applying portion is provided at each of two positions which are diametrically opposite to each other with respect to the axis of the driving shaft, and

wherein said coupling member receives a rotational force from the driving shaft to rotate by one of said rotational force receiving portions engaging to one of the rotational force applying portion and by the other of rotational force receiving portions engaging to the other of the rotational force applying portions, said one of said rotational force receiving portions being opposed to the other of said rotational force receiving portions, and said one of said rotational force applying portions being opposed to the other of said rotational force applying portions.

17. A rotating force transmitting part according to claim 16, wherein said expanding portion has a conical shape having an apex on the rotational axis of said coupling member, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the apex is opposed to the free end of the driving shaft, and said coupling member is over the free end of the driving shaft when the rotational force is transmitted to said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

18. A rotating force transmitting part according to claim 13, 14, 16 or 17, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

52. A rotating force transmitting part according to claim 13, 19, 22 or 49, wherein said rotating force receiving portion is engageable to said rotating force applying portion integrally rotatable with the driving shaft, wherein when said rotating force receiving portion receives the driving force for rotating said coupling member, and said rotating force receiving portion is inclined in a direction to receive a force toward the driving shaft.

54. A rotating force transmitting part according to claim 13, 19, 20 or 49, wherein a gap is provided between said rotating force transmitting portion and said rotating force receiving member so that coupling member is capable of tilting relative to the axis of said electrophotographic photosensitive drum substantially in all directions, wherein said rotating force transmitting portion is provided at an end of said electrophotographic photosensitive drum and is movable relative to said rotating force receiving member, and said rotating force transmitting portion and said rotating force receiving member are engageable to each other in a rotational direction of said coupling member.

19. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member for transmitting a rotational force to said electrophotographic photosensitive drum, said a rotational force receiving portion for engaging with the rotational force applying portion to receive a rotational force from the driving shaft, and a rotating force transmitting portion for transmitting the rotating force received through said rotating force receiving portion to said electrophotographic photosensitive drum;

a coupling member pivotable between a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum to said electrophotographic photosensitive drum and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position;

a rotating force receiving member for receiving the rotating force from said rotating force transmitting portion to rotate said electrophotographic photosensitive drum;

wherein said coupling member has a recess in which a rotational axis of said coupling member extends, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other, wherein said recess is over a free end of said driving shaft in the state in which process cartridge is mounted to said main assembly of the electrophotographic image forming apparatus, wherein said coupling member receives a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft, and wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the drive shaft by pivoting from said rotational force transmitting angular position to said disengaging angular position so that a part of said coupling member circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

20. A rotating force transmitting part according to claim 19, wherein said recess has a conical shape having an apex on the rotational axis of said coupling member, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the apex is opposed to the free end of the driving shaft, and said coupling member is over the free end of the driving shaft when the rotational force is transmitted to said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

21. A rotating force transmitting part according to claim 19 or 20, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

55. A rotating force transmitting part according to claim 21, 22, 40 or 49, wherein the main assembly of the electrophotographic image forming apparatus includes an urging member movable between an urging position and a retracted position retracted from the urging position, wherein when said process cartridge is mounted to said main assembly of the electrophotographic image forming apparatus, said coupling member moves to the pre-engagement angular position 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 said process cartridge.

22. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is mountable to and dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member engageable with said rotational force applying portion to receive a rotational force for rotating said electrophotographic photosensitive drum, said coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum to said electrophotographic photosensitive drum, a pre-engagement angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position, and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position, wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus in a direction substantially perpendicular to the axis of said electrophotographic photosensitive drum, said coupling member moves from the pre-engagement angular position to the rotational force transmitting angular position to be opposed to the driving shaft, and wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a direction substantially perpendicular to the axis of said electrophotographic photosensitive drum, said coupling member is disengaged from the driving shaft by moving from said rotational force transmitting angular position to said disengaging angular position.

23. A rotating force transmitting part according to claim 22, wherein said coupling member has a recess in which a rotational axis of said coupling member extends, wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, said process cartridge pivots from the pre-engagement angular position to the rotational force transmitting angular position so that a downstream part of said coupling member, with respect to the mounting direction in which said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus circumvents the driving shaft,

wherein said recess is over a free end of said driving shaft in the state in which said coupling member is positioned at said rotational force transmitting angular position, wherein said coupling member is rotated by a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft, and wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the drive shaft by pivoting from said rotational force transmitting angular position to said disengaging angular position so that a part of said coupling member circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

24. A rotating force transmitting part according to claim 23, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other.

25. A rotating force transmitting part according to claim 23, wherein said recess includes an expanding portion expanding toward a free end thereof, and wherein a plurality of said rotational force receiving portions are provided at regular intervals along a rotational direction of said coupling member, wherein the rotational force applying portion is provided at each of two positions which are diametrically opposite to each other with respect to the axis of the driving shaft, and

wherein said coupling member receives a rotational force from the driving shaft to rotate by one of said rotational force receiving portions engaging to one of the rotational force applying portion and by the other of rotational force receiving portions engaging to the other of the rotational force applying portions, said one of said rotational force receiving portions being opposed to the other of said rotational force receiving portions, and said one of said rotational force applying portions being opposed to the other of said rotational force applying portions.

26. A rotating force transmitting part according to claim 25, wherein said expanding portion has a conical shape having an apex on the rotational axis of said coupling member, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the apex is opposed to the free end of the driving shaft, and said coupling member is over the free end of the driving shaft when the rotational force is transmitted to said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

27. A rotating force transmitting part according to claim 25 or 26, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at the pre-engagement angular position, said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so that a downstream part thereof with respect to the mounting direction in which the process cartridge is mounted to the main assembly of the apparatus passes by the free end of the drive shaft, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

28. A rotating force transmitting part according to claim 24, wherein said coupling member includes a rotating force transmitting portion for transmitting the rotating force to said electrophotographic photosensitive drum, and a connecting portion between said rotating force receiving portion and said rotating force transmitting portion, wherein said rotating force receiving portion, said connecting portion, said rotating force transmitting portion are arranged along the rotational axis direction, and wherein when said process cartridge is moved in the direction substantially perpendicular to the driving shaft, said pre-engagement angular position is provided by said connecting portion contacting a fixed portion provided in the main assembly of the electrophotographic image forming apparatus.

29. A rotating force transmitting part according to claim 22, further comprising a maintaining member for maintaining said coupling member at the pre-engagement angular position, wherein said coupling member is maintained at the pre-engagement angular position by a force exerted by said maintaining member.

30. A rotating force transmitting part according to claim 29, wherein said maintaining member includes an elastic member capable of providing an elastic force to maintain said coupling member at the pre-engagement angular position, includes a friction member capable of providing a frictional force to maintain said coupling member at the pre-engagement angular position, includes a locking member capable of providing a locking force to maintain said coupling member at the pre-engagement angular position, or includes a magnetic member, provided in said coupling member, capable of providing a magnetic force to maintain said coupling member at the pre-engagement angular position.

56. A rotating force transmitting part according to claim 22, 31, 40 or 49, wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, said coupling member is opposed to a free end of the driving shaft by moving to the axial direction of the electrophotographic photosensitive drum and by pivoting from the pre-engagement angular position to the rotational force transmitting angular position.

31. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is mountable to and dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member engageable with said rotational force applying portion to receive a rotational force for rotating said electrophotographic photosensitive drum, said coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum to said electrophotographic photosensitive drum, a pre-engagement angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position, and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position,

wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, said process cartridge pivots from the pre-engagement angular position to the rotational force transmitting angular position so that a downstream part of said coupling member, with respect to the mounting direction in which said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus circumvents the driving shaft,

wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, an upstream part of said coupling member with respect to the dismounting direction in which said process cartridge is dismounted from the main assembly of the apparatus is behind the drive shaft as seen in the direction opposite the dismounting direction, and

wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the drive shaft by pivoting from said rotational force transmitting angular position to said disengaging angular position so that a part behind the drive shaft circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

32. A rotating force transmitting part according to claim 31, wherein said coupling member has a recess in which a rotational axis of said coupling member extends, and wherein said recess is over a free end of said driving shaft in the state in which said coupling member is positioned at said rotational force transmitting angular position, wherein said coupling member receives a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft.

33. A rotating force transmitting part according to claim 32, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other.

34. A rotating force transmitting part according to claim 32, wherein said recess includes an expanding portion expanding toward a free end thereof, and wherein a plurality of said rotational force receiving portions are provided at regular intervals along a rotational direction of said coupling member, wherein the rotational force applying portion is provided at each of two positions which are diametrically opposite to each other with respect to the axis of the driving shaft, and

wherein said coupling member receives a rotational force from the driving shaft to rotate by one of said rotational force receiving portions engaging to one of the rotational force applying portion and by the other of rotational force receiving portions engaging to the other of the rotational force applying portions, said one of said rotational force receiving portions being opposed to the other of said rotational force receiving portions, and said one of said rotational force applying portions being opposed to the other of said rotational force applying portions.

35. A rotating force transmitting part according to claim 34, wherein said expanding portion has a conical shape having an apex on the rotational axis of said coupling member, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the apex is opposed to the free end of the driving shaft, and said coupling member is over the free end of the driving shaft when the rotational force is transmitted to said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

36. A rotating force transmitting part according to claim 31, 32, 34 or 35, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at the pre-engagement angular position, said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so that a downstream part thereof with respect to the mounting direction in which the process cartridge is mounted to the main assembly of the apparatus passes by the free end of the drive shaft, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

37. A rotating force transmitting part according to claim 31, 32 or 33, wherein said coupling member includes a rotating force transmitting portion for transmitting the rotating force to said electrophotographic photosensitive drum, and a connecting portion between said rotating force receiving portion and said rotating force transmitting portion, wherein said rotating force receiving portion, said connecting portion, said rotating force transmitting portion are arranged along the rotational axis direction, and wherein when said process cartridge is moved in the direction substantially perpendicular to the driving shaft, said pre-engagement angular position is provided by said connecting portion contacting a fixed portion provided in the main assembly of the electrophotographic image forming apparatus.

38. A rotating force transmitting part according to claim 31, further comprising a maintaining member for maintaining said coupling member at the pre-engagement angular position, wherein said coupling member is maintained at the pre-engagement angular position by a force exerted by said maintaining member.

39. A rotating force transmitting part according to claim 38, wherein said maintaining member includes an elastic member capable of providing an elastic force to maintain said coupling member at the pre-engagement angular position, includes a friction member capable of providing a frictional force to maintain said coupling member at the pre-engagement angular position, includes a locking member capable of providing a locking force to maintain said coupling member at the pre-engagement angular position, or includes a magnetic member, provided in said coupling member, capable of providing a magnetic force to maintain said coupling member at the pre-engagement angular position.

40. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is mountable to and dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member for transmitting a rotational force to said electrophotographic photosensitive drum, said coupling member including a rotational force receiving portion for engaging with the rotational force applying portion to receive a rotational force from the driving shaft, and a rotational force transmitting portion for transmitting the rotational force received through said rotational force receiving portion to said electrophotographic photosensitive drum, wherein said coupling member is capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum through said rotating force transmitting portion to said electrophotographic photosensitive drum, a pre-engagement angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position, and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position;

a rotating force receiving member for receiving the rotating force from said rotating force transmitting portion to rotate said electrophotographic photosensitive drum;

wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, said process cartridge pivots from the pre-engagement angular position to the rotational force transmitting angular position in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum,

wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, an upstream part of said coupling member with respect to the dismounting direction in which said process cartridge is dismounted from the main assembly of the apparatus is behind the drive shaft as seen in the direction opposite the dismounting direction, and

wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the drive shaft by pivoting from said rotational force transmitting angular position to said disengaging angular position so that a part behind the drive shaft circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

41. A rotating force transmitting part according to claim 40, wherein said coupling member has a recess in which a rotational axis of said coupling member extends, wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, said process cartridge pivots from the pre-engagement angular position to the rotational force transmitting angular position so that a downstream part of said coupling member, with respect to the mounting direction in which said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus circumvents the driving shaft,

wherein said coupling member has a recess in which a rotational axis of said coupling member extends, and wherein said recess is over a free end of said driving shaft in the state in which said coupling member is positioned at said rotational force transmitting angular position, wherein said coupling member receives a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft, and

wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the drive shaft by pivoting from said rotational force transmitting angular position to said disengaging angular position so that a part behind the drive shaft circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

42. A rotating force transmitting part according to claim 40 or 41, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other.

43. A rotating force transmitting part according to claim 41, wherein said recess includes an expanding portion expanding toward a free end thereof, and wherein a plurality of said rotational force receiving portions are provided at regular intervals along a rotational direction of said coupling member, wherein the rotational force applying portion is provided at each of two positions which are diametrically opposite to each other with respect to the axis of the driving shaft, and

wherein said coupling member receives a rotational force from the driving shaft to rotate by one of said rotational force receiving portions engaging to one of the rotational force applying portion and by the other of rotational force receiving portions engaging to the other of the rotational force applying portions, said one of said rotational force receiving portions being opposed to the other of said rotational force receiving portions, and said one of said rotational force applying portions being opposed to the other of said rotational force applying portions.

44. A rotating force transmitting part according to claim 43, wherein said expanding portion has a conical shape having an apex on the rotational axis of said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

45. A rotating force transmitting part according to claim 40, 41, 43 or 44, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at the pre-engagement angular position, said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so that a downstream part thereof with respect to the mounting direction in which the process cartridge is mounted to the main assembly of the apparatus passes by the free end of the drive shaft, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

46. A rotating force transmitting part according to claim 40, wherein said coupling member includes a rotating force transmitting portion for transmitting the rotating force to said electrophotographic photosensitive drum, and a connecting portion between said rotating force receiving portion and said rotating force transmitting portion, wherein said rotating force receiving portion, said connecting portion, said rotating force transmitting portion are arranged along the rotational axis direction, and wherein when said process cartridge is moved in the direction substantially perpendicular to the driving shaft, said pre-engagement angular position is provided by said connecting portion contacting a fixed portion provided in the main assembly of the electrophotographic image forming apparatus.

47. A rotating force transmitting part according to claim 40, further comprising a maintaining member for maintaining said coupling member at the pre-engagement angular position, wherein said coupling member is maintained at the pre-engagement angular position by a force exerted by said maintaining member.

48. A rotating force transmitting part according to claim 47, wherein said maintaining member includes an elastic member capable of providing an elastic force to maintain said coupling member at the pre-engagement angular position, includes a friction member capable of providing a frictional force to maintain said coupling member at the pre-engagement angular position, includes a locking member capable of providing a locking force to maintain said coupling member at the pre-engagement angular position, or includes a magnetic member, provided in said coupling member, capable of providing a magnetic force to maintain said coupling member at the pre-engagement angular position.

49. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is mountable to and dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a coupling member for transmitting a rotational force to said electrophotographic photosensitive drum, said coupling member including a rotational force receiving portion for engaging with the rotational force applying portion to receive a rotational force from the driving shaft, and a rotational force transmitting portion for transmitting the rotational force received through said rotational force receiving portion to said electrophotographic photosensitive drum, wherein said coupling member is capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said electrophotographic photosensitive drum through said rotating force transmitting portion to said electrophotographic photosensitive drum, a pre-engagement angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position, and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum from said rotational force transmitting angular position;

a rotating force receiving member for receiving the rotating force from said rotating force transmitting portion to rotate said electrophotographic photosensitive drum;

wherein said coupling member has a recess in which a rotational axis of said coupling member extends, wherein a plurality of such rotational force receiving portions are provided on a phantom circle having a center on the rotational axis of said coupling member at positions substantially diametrically opposite to each other,

wherein when said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus, said process cartridge pivots from the pre-engagement angular position to the rotational force transmitting angular position so that a downstream part of said coupling member, with respect to the mounting direction in which said process cartridge is mounted to the main assembly of the electrophotographic image forming apparatus circumvents the driving shaft,

wherein said coupling member has a recess in which a rotational axis of said coupling member extends, and wherein said recess is over a free end of said driving shaft in the state in which said coupling member is positioned at said rotational force transmitting angular position, wherein said coupling member receives a rotational force through engagement, in a rotational direction of said coupling member, to the rotational force applying portion which is projected in a direction substantially perpendicular to an axis of the driving shaft adjacent to the free end of the driving shaft, and

wherein when said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus, said coupling member is disengaged from the drive shaft by pivoting from said rotational force transmitting angular position to said disengaging angular position so that a part behind the drive shaft circumvents the driving shaft in response to movement of said process cartridge in the direction substantially perpendicular to the axis of said electrophotographic photosensitive drum.

50. A rotating force transmitting part according to claim 49, wherein said expanding portion has a conical shape having an apex on the rotational axis of said coupling member, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the apex is opposed to the free end of the driving shaft, and said coupling member is over the free end of the driving shaft when the rotational force is transmitted to said coupling member, and wherein said rotational force receiving portions are provided at regular intervals in a rotational direction of said coupling member.

51. A rotating force transmitting part according to claim 49 or 50, wherein in the state in which coupling member is positioned at said rotational force transmitting angular position, the rotational axis of said coupling member is substantially coaxial with the axis of said electrophotographic photosensitive drum, wherein in the state in which coupling member is positioned at said disengaging angular position, the rotational axis of said coupling member is inclined relative to the axis of said electrophotographic photosensitive drum so as to permit an upstream portion of said coupling member passes by the free end of the driving shaft in a removing direction in which said process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus.

57. A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein said electrophotographic photosensitive drum is mountable to and dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, said rotating force transmitting part comprising:

a recess having an opening at a side opposite from said electrophotographic photosensitive drum with respect to the direction of the axis when said coupling member rotates;

a plurality of projected portions provided along a rotational direction of said coupling member with intervals and projected in a direction crossing with the rotational direction from a free-end edge portion of said recess;

rotating force receiving portions for engagement with said rotating force applying portion receiving the rotating force from the driving shaft in the state in which process cartridge is mounted to said main assembly of the apparatus, wherein said rotating force receiving portions are provided at said projected portions, respectively at positions equidistant from the axis of said coupling member interposing the axis of said coupling member;

a recess formed between said projected portions, said recess being recessed in the direction of the axis,

a rotating force transmitting portion for transmitting the rotating force from the rotating force applying portion through said rotating force receiving portion to said electrophotographic photosensitive drum;

a coupling member is pivotable between a rotational force transmitting angular position for transmitting the rotating force for rotating said electrophotographic photosensitive drum through said rotating force transmitting portion to said electrophotographic photosensitive drum, and a pre-engagement angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum and away from the rotational force transmitting angular position, and between the rotational force transmitting angular position and a disengaging angular position in which said coupling member is inclined away from the axis of said electrophotographic photosensitive drum and away from the rotational force transmitting angular position.