DEVELOPING DEVICE, DEVELOPING CARTRIDGE, ROTATIONAL FORCE TRANSMITTING PART AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS

• US 20100054823A1
• Filed: 08/26/2009
• Published: 03/04/2010
• Est. Priority Date: 08/27/2008
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ueno, Takahito, Miyabe, Shigeo, Takasaka, Atsushi
• Granted Patent: US 8,874,004 B2
• Time in Patent Office: Days
• US Class Current: 399/286
• CPC Class Codes: F16D 1/10 Quick-acting couplings in which the parts are connected by simply bringing them together axially
• CPC Class Codes: F16D 3/2052 having two pins
• CPC Class Codes: G03G 15/0121 for developing
• CPC Class Codes: G03G 15/0152 onto which the monocolour toner images are superposed before common transfer from the recording member
• CPC Class Codes: G03G 15/0173 plural rotations of recording member to produce multicoloured copy, e.g. rotating set of developing units G03G15/0163 takes precedence
• 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 2215/0177 Rotating set of developing units
• CPC Class Codes: G03G 2221/1657 transmitting mechanical drive power

Abstract

A developing device is usable with an electrophotographic image forming apparatus including a shaft and a rotary unit mounting the device. When mounted, the device is movable perpendicular to a shaft axial direction in response to movement of the rotary unit and the shaft is not movable in that direction. The device includes a developing roller that contacts and separates from a drum in response to movement of the rotary unit, and a coupler transmitting a rotating force to the roller. The coupler includes a portion engaging the shaft to receive a rotating force and a portion transmitting the received rotating force to the roller. The coupler takes a first position for transmitting the rotational force to the roller, a position before the coupler engages the shaft and is inclined away from the first position, and a position for the disengagement of the coupler and the shaft.

Claims

1. A developing device usable with an electrophotographic image forming apparatus, said apparatus including a driving shaft rotatable by a motor and having a rotating force applying portion, and a movable member, said developing device being mountable to the movable member, and said developing device being movable in a direction substantially perpendicular to an axial direction of the driving shaft in response to movement of the movable member in one direction with said developing device mounted to the movable member, wherein said driving shaft is not movable in a direction perpendicular to an axix thereof, said developing device comprising:

i) a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, said developing roller being rotatable about an axis, wherein said developing roller is contacted to and separated from said electrophotographic photosensitive member drum in response to movement of said movable member; and

ii) a coupling member for transmitting a rotating force to said developing roller, said coupling member including, a rotating force receiving portion engageable with the rotating force applying portion to receive a rotating 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 developing roller, said coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said developing roller to said developing roller, a pre-engagement angular position which is taken before said coupling member is engaged with the rotating force applying portion and in which said coupling member is inclined away from said rotational force transmitting angular position, and a disengaging angular position which is taken for said coupling member to disengage from the driving shaft and in which said coupling member is inclined away from the rotational force transmitting angular position in a direction opposite to said pre-engagement angular position,

wherein in response to a movement of said developing device when the movable member moves in said one direction, said coupling member moves from the pre-engagement angular position to the rotational force transmitting angular position, and wherein when the movable member makes a further movement in said one direction, in response to the further movement, said coupling member is moved from said rotational force transmitting anglar position to said disengaging angular position to disengage said coupling member from said driving shaft, and

wherein said developing roller is contacted to said electrophotographic photosensitive member in response to the movement of said developing device in a state that developing roller is being rotated through engagement between said coupling member and said rotating force applying portion.

2. A device according to claim 1, wherein said coupling member moves from said rotational force transmitting angular position to said disengaging angular position by the movement of the movable member in said one direction so that part of said coupling member circumvents the driving shaft in response to movement of said developing device in the direction substantially perpendicular to the axis of said developing roller.

3. A device 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 by movement of said coupling member from said pre-engagement angular position to said rotational force transmitting angular position.

4. A device according to claim 1, wherein when said coupling member is in said rotational force transmitting angular position, said rotating force receiving portion is engaged, in a direction of rotation of said coupling member, with the rotating force applying portion which is projected in a direction perpendicular to the axial direction of said driving shaft said coupling member by which said coupling member receives a rotating force from the driving shaft to rotate.

5. A device according to claim 4, wherein said coupling member moves from said rotational force transmitting angular position to said disengaging angular position to disengage from the driving shaft by the further movement of the movable member in said one direction so that part of said coupling member circumvents the driving shaft in response to movement of said developing device in the direction substantially perpendicular to the axis of said developing roller.

6. A device according to claim 1, 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.

7. A device according to claim 1, wherein said rotational force receiving portion is provided projected at each of two positions of an edge portion of said flat portion interposing the central portion, wherein the rotational force applying portion is provided projected in a direction perpendicular to the axis of the driving shaft at each of two positions opposite to each other, 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.

8. A device according to claim 1, wherein said coupling member has a circular flat portion at a free end thereof, and said recess is disposed at a central portion of said circular flat portion, said recess includes an expanding portion expanding toward a free end thereof.

9. A device according to claim 8, further comprising an elastic member for elastically urging said coupling member with such an elastic force as to permit said coupling member to move from said pre-engagement angular position to said rotational force transmitting angular position to maintain said coupling member at said pre-engagement angular position and as to permit said coupling member to moves from said rotational force transmitting angular position to said disengaging angular position.

10. A device according to claim 1, wherein said coupling member is provided in a position away from said axis of said developing roller with respect to a direction perpendicular to said axis of said developing roller.

11. A device according to claim 9, wherein said rotating force transmitting portion is disposed in a side opposite from said rotating force receiving portion, and wherein the rotating force received by said rotating force transmitting portion is transmitted to said developing roller through said rotating force receiving portion and said driving force transmission member.

12. A device according to claim 1, wherein said developing device contains a yellow color developer, a magenta color developer, a cyan color developer or a black color developer, and is a developing cartridge detachably mountable to said movable member in the form of a developing rotary.

13. An electrophotographic image forming apparatus for forming an image on a recording material, said electrophotographic image forming apparatus comprising:

i) a driving shaft rotatable by a motor and having a rotating force applying portion, wherein said driving shaft is not movable in a direction perpendicular to an axix thereof;

ii) a movable member;

iii) a developing device which is movable in a direction substantially perpendicular to an axial direction of the driving shaft in response to movement of the movable member in a state that developing device is mounted to said movable member, in response to the moment of said movable member, said developing roller including

a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive drum, said developing roller being rotatable about an axis, wherein said developing roller is contacted to and separated from said electrophotographic photosensitive member drum in response to movement of said movable member;

iv) a coupling member for transmitting a rotating force to said developing roller, said coupling member including, a rotating force receiving portion engageable with the rotating force applying portion to receive a rotating 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 developing roller, said coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating said developing roller to said developing roller, a pre-engagement angular position which is taken before said coupling member is engaged with the rotating force applying portion and in which said coupling member is inclined away from said rotational force transmitting angular position, and a disengaging angular position which is taken for said coupling member to disengage from the driving shaft and in which said coupling member is inclined away from the rotational force transmitting angular position in a direction opposite to said pre-engagement angular position to disengage from the driving shaft,

wherein in response to a movement of said developing device when the movable member moves in said one direction, said coupling member moves from the pre-engagement angular position to the rotational force transmitting angular position, and wherein when the movable member makes a further movement in said one direction, in response to the further movement, said coupling member is moved from said rotational force transmitting angular position to said disengaging angular position to disengage said coupling member from said driving shaft, and

wherein said developing roller is contacted to said electrophotographic photosensitive member in response to the movement of said developing device in a state that developing roller is being rotated through engagement between said coupling member and said rotating force applying portion.

14. An apparatus according to claim 13, wherein said coupling member moves from said rotational force transmitting angular position to said disengaging angular position by the movement of the movable member in said one direction so that part of said coupling member circumvents the driving shaft in response to movement of said developing device in the direction substantially perpendicular to the axis of said developing roller.

15. An apparatus 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 by movement of said coupling member from said pre-engagement angular position to said rotational force transmitting angular position.

16. An apparatus according to claim 13, wherein when said coupling member is in said rotational force transmitting angular position, said rotating force receiving portion is engaged, in a direction of rotation of said coupling member, with the rotating force applying portion which is projected in a direction perpendicular to the axial direction of said driving shaft said coupling member by which said coupling member receives a rotating force from the driving shaft to rotate.

17. An apparatus according to claim 16, wherein said coupling member moves from said rotational force transmitting angular position to said disengaging angular position to disengage from the driving shaft by the further movement of the movable member in said one direction so that part of said coupling member circumvents the driving shaft in response to movement of said developing device in the direction substantially perpendicular to the axis of said developing roller.

18. An apparatus according to claim 13, 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.

19. An apparatus according to claim 13, wherein said rotational force receiving portion is provided projected at each of two positions of an edge portion of said flat portion interposing the central portion, wherein the rotational force applying portion is provided projected in a direction perpendicular to the axis of the driving shaft at each of two positions opposite to each other, 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.

20. An apparatus according to claim 13, wherein said coupling member has a circular flat portion at a free end thereof, and said recess is disposed at a central portion of said circular flat portion, said recess includes an expanding portion expanding toward a free end thereof.

21. An apparatus according to claim 20, further comprising an elastic member for elastically urging said coupling member with such an elastic force as to permit said coupling member to move from said pre-engagement angular position to said rotational force transmitting angular position to maintain said coupling member at said pre-engagement angular position and as to permit said coupling member to moves from said rotational force transmitting angular position to said disengaging angular position.

22. An apparatus according to claim 13, wherein said coupling member is provided in a position away from said axis of said developing roller with respect to a direction perpendicular to said axis of said developing roller.

23. An apparatus according to claim 21, wherein said rotating force transmitting portion is disposed in a side opposite from said rotating force receiving portion, and wherein the rotating force received by said rotating force transmitting portion is transmitted to said developing roller through said rotating force receiving portion and said driving force transmission member.

24. An apparatus according to claim 13, wherein said developing device contains a yellow color developer, a magenta color developer, a cyan color developer or a black color developer, and is a developing cartridge detachably mountable to said movable member in the form of a developing rotary.

25. A developing device usable with an electrophotographic image forming apparatus, said apparatus including a driving shaft rotatable having a rotating force applying portion, and a rotatable rotary, said developing device being movable in a direction substantially perpendicular to an axial direction of the driving shaft in response to rotation of said rotary with said developing device mounted to said rotary, said developing device comprising:

i) a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive member drum;

ii) a developer accommodating portion for accommodating a developer for use by said developing roller to developing the electrostatic latent image;

iii) a coupling member for transmitting a rotating force to said developing roller in a state that developing cartridge is mounted to said rotary, said coupling member including a rotating force receiving portion for engaging with the rotating force applying portion to receive said driving shaft the rotating force from the driving shaft, wherein the driving shaft is not movable in a direction substantially perpendicular to an axial direction of said driving shaft;

iv) a regulating member including a regulating portion for regulating said coupling member at a pre-engagement angular position before engagement with the driving shaft, and including a permitting portion for permitting said coupling member to revolve substantially;

v) an elastic member for elastically urging said coupling member to position said coupling member at the regulating portion,

wherein when said rotary rotates, said coupling member moves from the pre-engagement angular position to a rotational force transmitting angular position the response to movement of said coupling member from the regulating portion To the permitting portion against an elastic force of said elastic member by said coupling member contacting said driving shaft member with movement of said developing cartridge, and when said rotary further rotates, said coupling member moves from the rotational force transmitting angular position to a disengaging angular position to disengage said coupling member from the driving shaft against an elastic force of said elastic member.

26. A device according to claim 25, wherein said regulating portion is provided with a relatively narrow portion, and said permitting portion is provided with a relatively wide portion, wherein said coupling member is provided with a projection at a trailing end which is opposite from said rotating force receiving portion, and wherein when said projected portion is in said narrow portion, an inclining direction of said coupling member is regulated at the pre-engagement angular position, and when said projected portion in the wide portion, said coupling member is substantially revolvable.

27. A device according to claim 26, further comprising a developer supplying roller for supplying to said developing roller a developer accommodated in said developer accommodating portion, wherein said grooves are surrounded by a circular portion, wherein said circular portion is provided with a rotatable member rotatably engaged therewith, said rotatable member being provided with a first gear portion for transmitting the rotating force receiving from the driving shaft to said developing roller, a second gear portion for transmitting the rotating force to said developer supplying roller, and a wherein said coupling member is substantially revolvably to an inside of said rotatable member.

28. A device according to claim 25, wherein said coupling member is provided, at a free end side where said rotating force receiving portion is provided, with a circular flat portion and a circular recess provided at a center of said flat portion, wherein said recess is engaged with the free end of the driving shaft in a state that coupling member is in the rotational force transmitting angular position, and wherein said rotating force receiving portion is projected from an edge of said flat portion and is provided at each of the positions opposed to each other interposing the center of said flat portion.

29. A device according to claim 27, wherein said coupling member is provided, at a rear end side which is opposite from the free end side, a spherical configuration portion which is revolvably mounted to an inside of said rotatable member such that coupling member is confined from movement toward the free end side in a longitudinal direction of said coupling member, thus preventing said coupling member from disengaging from said rotatable member, and wherein rotating force transmitting portion is projected from said spherical configuration portion in a direction perpendicular to the longitudinal direction.

30. A device according to claim 25, further comprising a developer supplying roller for supplying to said developing roller a developer Accommodated in said developer accommodating portion, wherein a direction of inclination of said coupling member in said pre-engagement angular position is between a rotation axis of said developing roller and a rotation axis of said developer supplying roller.

31. A device according to claim 27, wherein when said coupling member is in the permitting portion, a gap is provided between a rotating force transmitting portion of said coupling for transmitting the rotating force received from said rotating force receiving portion to said developing roller and a rotating force receiving portion of said rotatable member for receiving the rotating force from said rotating force transmitting portion so that coupling member is substantially revolvable, wherein said rotating force transmitting portion is movable relative to said rotating force receiving portion, and said rotating force transmitting portion and said rotating force receiving portion are contacted to each other with respect to a rotational direction of said coupling member.

40. An apparatus according to claim 25, wherein said elastic member is mounted to a mounting portion at its one end and is movably engaged with a recess for regulating the other end from moving in the axial direction of the driving shaft at the other end thereof.

41. An apparatus according to claim 40, wherein said developing cartridge includes a developer supplying roller for supplying to said developing roller a developer accommodated in said developer accommodating portion, wherein said one end of said elastic member is mounted to a supporting member supporting a rotatable member provided with a first gear portion for transmitting the rotating force receiving from the driving shaft to said developing roller, a second gear portion for transmitting the rotating force to said developer supplying roller, and said other end is movably engaged with a recess provided in said supporting member.

42. An apparatus according to claim 31, wherein said coupling member is made of polyacetal resin material.

32. An electrophotographic image forming apparatus for forming an image on a recording material, said apparatus comprising:

i) a driving shaft including a rotating force applying portion;

ii) a rotatable rotary;

a developing cartridge movable in a direction substantially perpendicular to an axial direction of the driving shaft in response to rotation of said rotary with said developing device mounted to said rotary;

a developing roller for developing an electrostatic latent image formed on an electrophotographic photosensitive member drum;

a developer accommodating portion for accommodating a developer for use by said developing roller to developing the electrostatic latent image;

iii) a coupling member for transmitting a rotating force to said developing roller in a state that developing cartridge is mounted to said rotary, said coupling member including a rotating force receiving portion for engaging with the rotating force applying portion to receive said driving shaft the rotating force from the driving shaft, wherein the driving shaft is not movable in a direction substantially perpendicular to an axial direction of said driving shaft;

iv) a regulating member including a regulating portion for regulating said coupling member at a pre-engagement angular position before engagement with the driving shaft, and including a permitting portion for permitting said coupling member to revolve substantially; and

v) an elastic member for elastically urging said coupling member to position said coupling member at the regulating portion,

wherein when said rotary rotates, said coupling member moves from the pre-engagement angular position to a rotational force transmitting angular position the response to movement of said coupling member from the regulating portion To the permitting portion against an elastic force of said elastic member by said coupling member contacting said driving shaft member with movement of said developing cartridge, and when said rotary further rotates, said coupling member moves from the rotational force transmitting angular position to a disengaging angular position to disengage said coupling member from the driving shaft against an elastic force of said elastic member.

33. An apparatus according to claim 32, wherein said regulating portion is provided with a relatively narrow portion, and said permitting portion is provided with a relatively wide portion, wherein said coupling member is provided with a projection at a trailing end which is opposite from said rotating force receiving portion, and wherein when said projected portion is in said narrow portion, an inclining direction of said coupling member is regulated at the pre-engagement angular position, and when said projected portion in the wide portion, said coupling member is substantially revolvable.

34. An apparatus according to claim 33, further comprising a developer supplying roller for supplying to said developing roller a developer accommodated in said developer accommodating portion, wherein said grooves are surrounded by a circular portion, wherein said circular portion is provided with a rotatable member rotatably engaged therewith, said rotatable member being provided with a first gear portion for transmitting the rotating force receiving from the driving shaft to said developing roller, a second gear portion for transmitting the rotating force to said developer supplying roller, and a wherein said coupling member is substantially revolvably to an inside of said rotatable member.

35. An apparatus according to claim 34, wherein said coupling member is provided, at a free end side where said rotating force receiving portion is provided, with a circular flat portion and a circular recess provided at a center of said flat portion, wherein said recess is engaged with the free end of the driving shaft in a state that coupling member is in the rotational force transmitting angular position, and wherein said rotating force receiving portion is projected from an edge of said flat portion and is provided at each of the positions opposed to each other interposing the center of said flat portion.

36. An apparatus according to claim 34, wherein said coupling member is provided, at a rear end side which is opposite from the free end side, a spherical configuration portion which is revolvably mounted to an inside of said rotatable member such that coupling member is confined from movement toward the free end side in a longitudinal direction of said coupling member, thus preventing said coupling member from disengaging from said rotatable member, and wherein rotating force transmitting portion is projected from said spherical configuration portion in a direction perpendicular to the longitudinal direction.

37. An apparatus according to claim 36, further comprising a developer supplying roller for supplying to said developing roller a developer Accommodated in said developer accommodating portion, wherein a direction of inclination of said coupling member in said pre-engagement angular position is between a rotation axis of said developing roller and a rotation axis of said developer supplying roller.

38. An apparatus according to claim 37, wherein when said coupling member is in the permitting portion, a gap is provided between a rotating force transmitting portion of said coupling for transmitting the rotating force received from said rotating force receiving portion to said developing roller and a rotating force receiving portion of said rotatable member for receiving the rotating force from said rotating force transmitting portion so that coupling member is substantially revolvable, wherein said rotating force transmitting portion is movable relative to said rotating force receiving portion, and said rotating force transmitting portion and said rotating force receiving portion are contacted to each other with respect to a rotational direction of said coupling member.

39. An apparatus according to claim 32, wherein said rotary has a rotation axis which is single.

43. A rotating force transmitting part usable with a developing cartridge, said developing cartridge being mountable to a main assembly of an electrophotographic image forming apparatus including a driving shaft, and movable in a direction substantially perpendicular to an axial direction of the driving shaft, developing cartridge being provided with a regulating member including a permitting portion and a regulating portion, said rotating force transmitting part comprising:

a recess provided at one longitudinal end of said rotating force transmitting part and engageable with the driving shaft when said developing cartridge is mounted to the main assembly of the apparatus;

a spherical portion provided at the other end;

a plurality of projections interposing a center of said recess and projected away from said spherical portion in a longitudinal direction of said rotating force transmitting part for receiving the rotational force from the driving shaft which is provided in the main assembly of the apparatus such that it does not move in a direction substantially perpendicular to the axial direction of said driving shaft in a state that developing cartridge is mounted to the main assembly of the apparatus;

a first projected portion projected from said spherical portion away from said one end, said projected portion being revolvable between said permitting portion for permitting substantial revolution of said rotating force transmitting part and said regulating portion for regulating an inclination angle position of said rotating force transmitting part in a state that rotating force transmitting part is mounted to said developing cartridge; and

a plurality of second projected portions provided between said projections and said first projected portion and interposing said spherical portion, said second projected portions being projected outwardly from spherical portion, said second projected portions are effective to transmit the rotational force received from the driving shaft by the projections to the developing roller.

44. A rotating force transmitting part according to claim 43, further comprising a circular flat portion at a free end side where said projection is provided, wherein said recess is provided at a center of said flat portion, said projections project from an edge of said flat portion and are opposed to each other interposing the center of said flat portion.

45. A rotating force transmitting part according to claim 44, wherein said projections are provided on a phantom circle about the center.

46. A rotating force transmitting part according to claim 45, wherein said first and second projected portions have columnar shapes.