Cartridge

1. A cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, the main assembly including a main assembly side feeding member for feeding toner toward a main assembly side toner accommodating portion, the cartridge comprising:

a casing having a chamber;

a photosensitive drum rotatably supported by the casing, with a part of the photosensitive drum being positioned in the chamber;

a discharge opening in fluid communication with the chamber such that toner may be discharged from the chamber, through the discharge opening, to the main assembly side feeding member; and

a coupling member configured to transmit a rotational force to the main assembly side feeding member through engagement therebetween, the coupling member being positioned adjacent to the discharge opening such that the toner can move from the chamber to the coupling member and the discharge opening,

wherein the coupling member is movable between a first position for transmitting the rotational force to the main assembly side feeding member and a second position retracted from the first position.

2. A cartridge according to claim 1 , wherein a distance between the second position and a rotational axis of the photosensitive drum is shorter than a distance between the first position and the rotational axis of the photosensitive drum.

3. A cartridge according to claim 1 , further comprising a moving force receiving portion for receiving from the main assembly of the electrophotographic image forming apparatus a force for moving the coupling member from the second position to the first position.

4. A cartridge according to claim 1 , wherein the coupling member is in the second position in a free state thereof.

5. A cartridge according to claim 1 , further comprising an urging member for urging the coupling member toward the second position.

6. A cartridge according to claim 1 , wherein the coupling member is movable relative to the photosensitive drum.

7. A cartridge according to claim 1 , further comprising a drive transmitting portion for transmitting the rotational force from the photosensitive drum to the coupling member.

8. A cartridge according to claim 1 , wherein the coupling member is configured to be driven by rotation of the photosensitive drum.

9. A cartridge according to claim 1 , further comprising a developing roller for developing a latent image on the photosensitive drum,

wherein the coupling member is configured to be driven by rotation of the developing roller.

10. A cartridge according to claim 1 , further comprising:

a developing roller for developing a latent image on the photosensitive drum; and

a toner supplying roller for supplying toner to the developing roller,

wherein the coupling member is rotatable in interrelation rotation of the toner supplying roller.

11. A cartridge according to claim 1 , further comprising:

a developing roller for developing a latent image on the photosensitive drum; and

a toner supplying roller for supplying toner to the developing roller,

wherein the coupling member is configured to be driven by rotation of the toner supplying roller.

12. A cartridge according to claim 1 , further comprising a drive inputting portion for receiving a rotational force from the main assembly of the electrophotographic image forming apparatus,

wherein the cartridge is configured to transmit the rotational force received by the drive inputting portion to the coupling member.

13. A cartridge according to claim 12 , further comprising:

a developing roller for developing a latent image on the photosensitive drum, and

a toner supplying roller for supplying toner to the developing roller,

wherein the developer supplying roller is provided with the drive inputting portion.

14. A cartridge according to claim 13 , wherein the cartridge is configured to transmit the rotational force received by the drive inputting portion to the coupling member through the developing roller.

15. A cartridge according to claim 1 , wherein the coupling member is movable between the first position and the second position in a direction crossing an axial direction of the photosensitive drum, and the coupling member is closer to an axis of the photosensitive drum when the coupling member is in the second position than when the coupling member is in the first position.

16. A cartridge according to claim 1 , wherein the coupling member is configured such the coupling member engages with a coupling portion of the main assembly side feeding member when the coupling member is in the first position, and the coupling portion disengages from the coupling portion of the main assembly side feeding member when the coupling member is in the second position.