Process cartridge and electrophotographic image forming apparatus having an improved driving system

A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, wherein said main assembly includes a motor, a rotatable driving member for receiving a driving force from said motor, and a non-twisted projection which is substantially coaxial with said rotatable driving member, said process cartridge comprising:

• an electrophotographic photosensitive drum;
• process means actable on said photosensitive drum;
• and
• a non-twisted recess engageable with said projection, said recess being provided at a longitudinal end of said photosensitive drum, wherein when said rotatable driving member starts rotation, said recess and said projection are contacted to each other at least at three positions to trasmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection.

A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus for forming an image on a recording material, said main assembly including a motor, a rotatable driving member for receiving a driving force from said motor and one of a non-twisted recess and non-twisted projection having a non-circular cross-section and substantially coaxial with a rotation axis of said rotatable driving member, said process cartridge comprising:

• a rotatable electrophotographic photosensitive drum;
• process means actable on said photosensitive drum;
• and
• the other of said non-twisted projection and non-twisted recess provided at a longitudinal end of said photosensitive drum, having a non-circular cross-section and being substantially coaxial with a rotating axis of said photosensitive drum, wherein said other of said projection and recess of said photosensitive drum has such a dimension and configuration that it can take a first relative position with respect to said one of said recess and projection of said rotatable driving member in which relative rotational movement therebetween is permitted, and a second relative rotational position with respect to said one of said recess and projection of said driving rotatable member in which relative rotational movement is prevented in one rotational direction, while the rotation axis of said rotatable driving member and the rotation axis of said photosensitive drum are substantially aligned, wherein when said rotatable driving member starts rotation, said recess and said projection are contacted to each other at least at three positions to transmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection.

An electrophotographic image forming apparatus for forming an image on a recording material, to which apparatus a process cartridge is detachably mountable, said apparatus comprising:

• (a) a motor;
• (b) a rotatable driving member for receiving a driving force from said motor;
• (c) a non-twisted recess which is substantially coaxial with said rotatable driving member;
• (d) a mounting member for detachably mounting a process cartridge, said process cartridge including:
• an electrophotographic photosensitive drum;
• process means actable on said photosensitive drum;
• and
• a non-twisted projection engageable with said recess, said projection being provided at a longitudinal end of said photosensitive drum, wherein when said rotatable driving member starts rotation, said recess and said projection are contacted to each other at least at three positions to transmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection;
• and
• (e) a feeding member for feeding the recording material.

An electrophotographic image forming apparatus for forming an image on a recording material, to which a process cartridge is detachably mountable, said apparatus comprising:

• (a) a motor;
• (b) a driving rotatable member for receiving a driving force from said motor;
• (c) a non-twisted projection which is substantially coaxial with said driving rotatable member;
• and
• (d) a mounting member for detachably mounting a process cartridge, said process cartridge including:
• an electrophotographic photosensitive drum;
• process means actable on said photosensitive drum:
• and
• a non-twisted recess engageable with said projection, said recess being provided at a longitudinal end of said photosensitive drum, wherein when said rotatable driving member starts rotation, said recess and said projection are contacted to each other at least at three positions to transmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection.

A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, wherein said main assembly includes a motor, a rotatable driving member for receiving a driving force from the motor, and a non-twisted recess which is substantially coaxial with said rotatable driving member, wherein said recess has a substantially triangular cross-section, said process cartridge comprising:

• an electrophotographic photosensitive drum;
• a charging member for charging said photosensitive drum;
• and
• a non-twisted projection having a substantially triangular cross-section and engageable with said recess, said projection being provided at a longitudinal end of said photosensitive drum, wherein when said rotatable driving member starts rotation, said recess and said projection are contacted to each other at least at three positions to transmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection.

A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, wherein said main assembly includes a motor, a rotatable driving member for receiving a driving force from said motor, and a non-twisted projection which has a substantially triangular cross-section and which is substantially coaxial with said rotatable driving member, said process cartridge comprising:

• an electrophotographic photosensitive drum;
• a charging member for charging said photosensitive drum;
• and
• a non-twisted recess engageable with said projection, wherein said recess has a substantially triangular cross-section, said recess being provided at a longitudinal end of said photosensitive drum, wherein when said rotatable driving member starts rotation, said recess and said projection are contacted to each other at least at three positions to transmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection.

An electrophotographic image forming apparatus for forming an image on a recording material, to which apparatus a process cartridge is detachably mountable, said apparatus comprising:

• (a) a motor;
• (b) a driving rotatable member for receiving a driving force from said motor;
• (c) a non-twisted recess which is substantially coaxial with said driving rotatable member and has a substantially triangular cross-section;
• (d) a mounting member for detachably mounting said process cartridge, said process cartridge including:
• an electrophotographic photosensitive drum;
• a charging member for charging said photosensitive drum;
• and
• a non-twisted, substantially triangular projection engageable with said recess, said projection being provided at a longitudinal end of said photosensitive drum, wherein when said rotatable driving member starts rotation, said recess and said projection are contacted to each other at least at three positions to transmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection;
• and
• (e) a feeding member for feeding the recording material.

An electrophotographic image forming apparatus for forming an image on a recording material, to which apparatus a process cartridge is detachably mountable, said apparatus comprising:

• (a) a motor
• (b) a driving rotatable member for receiving a driving force from said motor;
• (c) a non-twisted, substantially triangular projection which is substantially coaxial with said driving rotatable member;
• (d) a mounting member for detachably mounting said process cartridge, said process cartridge including:
• an electrophotographic photosensitive drum;
• a charging member for charging said photosensitive drum;
• and
• a non-twisted recess engageable with said projection, wherein said recess has a substantially triangular cross-section and is provided at a longitudinal end of said photosensitive drum, wherein when said rotatable driving member starts rotation, said recess and projection are contacted to each other at least at three positions to transmit rotational driving force from said rotatable driving member to said photosensitive drum through engagement between said recess and said projection.