Photosensitive drum unit, assembling method therefor, and disassembling method therefor

1. A rotatable developer carrying member unit comprising:

a rotatable developer carrying member having a cylindrical shape configured to carry developer on a peripheral surface thereof;

a rotational force receiving member for receiving a rotational force for rotating the rotatable developer carrying member, the rotational force receiving member including a rotational force receiving portion for receiving the rotational force at one end portion side thereof and a portion-to-be-engaged at another end portion side thereof;

a spherical member including a spherical portion, a projected portion projected from the spherical portion, and an engaging portion for engaging with the portion-to-be-engaged;

a rotatable member accommodating the spherical member, the rotatable member including (i) a hole portion accommodating the spherical portion and having an opening that opens outward in a longitudinal direction of the rotatable developer carrying member, (ii) a groove portion that continues from the hole portion and accommodates the projected portion so as to be capable of receiving the rotational force from the projected portion, and (iii) a limiting portion for limiting inward movement of the spherical portion in the longitudinal direction of the rotatable developer carrying member; and

a closing member capable of partially covering the opening of the hole portion and capable of being mounted to the rotatable member to limit outward movement of the spherical portion in the longitudinal direction of the rotatable developer carrying member,

wherein one of the engaging portion and the portion-to-be-engaged includes a male screw portion and the other of the engaging portion and the portion-to-be-engaged includes a female screw portion.

2. A rotatable developer carrying member unit according to claim 1 , wherein the rotatable developer carrying member includes a gear portion.

3. A rotatable developer carrying member unit comprising:

a rotatable developer carrying member having a cylindrical shape configured to carry developer on a peripheral surface thereof;

a rotational force receiving member for receiving a rotational force for rotating the rotatable developer carrying member, the rotational force receiving member including a rotational force receiving portion for receiving a rotational force at one end portion side thereof and a portion-to-be-engaged at another end portion side thereof;

a spherical member including a spherical portion, a projected portion projected from the spherical portion, and an engaging portion for engaging with the portion-to-be-engaged;

a rotatable member accommodating the spherical member, the rotatable member including (i) a hole portion that opens outwardly in a longitudinal direction of the rotatable developer carrying member, with the hole portion accommodating the spherical portion, (ii) a groove portion that continues from the hole portion and accommodates the projected portion so as to be capable of receiving the rotational force from the projected portion, and (iii) a limiting portion, provided at one end portion of the hole portion, for limiting inward movement of the spherical portion in the longitudinal direction of the rotatable developer carrying member; and

a regulating portion, provided at the other end portion of the hole portion, for limiting outward movement of the spherical portion in the longitudinal direction of the rotatable developer carrying member,

wherein one of the engaging portion and the portion-to-be-engaged includes a male screw portion and the other of the engaging portion and the portion-to-be-engaged includes a female screw portion.

4. A rotatable developer carrying member unit according to claim 3 , wherein the rotatable developer carrying member includes a gear portion.