A Process cartridge includes a photosensitive drum and a coupling member operatively connected to the photosensitive drum, with the coupling member including an arm portion and a projection projecting from the arm portion, the arm portion being capable of transmitting driving force from the projection towards the photosensitive drum. The arm portion of the coupling member extends from a point that is upstream in the rotational direction of the photosensitive drum towards a point that is downstream in the rotation direction of the photosensitive drum.

A drum unit for a cartridge includes a photosensitive drum and a coupling member provided adjacent to an end of the photosensitive drum. The coupling member includes an arm portion, and a projection projected from the arm portion in a direction towards a rotational axis of the coupling member, with a part of the projection inclined relative to the rotational axis of the coupling member. The arm portion extends in a circumferential direction of the coupling member, and, as measured in a direction perpendicular to the rotational axis of the coupling member, a distance between the inclined part of the projection and the rotational axis of the coupling member increases as the distance in the direction of the rotational axis of the coupling member to another end of the photosensitive drum decreases.

A torsion bar includes a central portion extending in an axial direction about a longitudinal axis. The torsion bar also includes a first end portion having a splined outer surface, the first end portion disposed proximate a first end of the torsion bar, the first end portion spaced from the central portion with a first annular groove extending circumferentially about the torsion bar.

A drum unit for a cartridge includes a photosensitive drum and a coupling member rotatable about a rotational axis thereof, the coupling member being operatively connected to the photosensitive drum. The coupling member includes a movable extended portion that extends in a first direction, and a projection projecting from the extended portion in a second direction that crosses the first direction, the projection being capable of transmitting a driving force to the photosensitive drum. At least a part of the projection is positioned inside of the photosensitive drum.

A drum unit for a cartridge includes a photosensitive drum and a coupling member having a rotational axis, with the coupling member being operatively connected to the photosensitive drum. The coupling member includes a cylindrical portion having an outer surface and an inner surface that extends about the rotational axis of the coupling member, an arm portion extending from the inner surface of the cylindrical portion, and a projection projecting from the arm portion in a direction toward the rotational axis of the coupling member. The arm portion and the projection are movable relative to the inner surface.

To develop a conventional coupling for transmitting a driving force. A coupling member is provided with a supporting portion for movable supporting a driving force receiving portion for receiving a driving force.

A cartridge includes a rotatable member configured to carry toner on a surface and a coupling member operatively connected to the rotatable member. The coupling member is rotatable about a rotational axis thereof, and the coupling member includes an extended portion that is movable in a direction perpendicular to the rotational axis, and a projection projecting from the extended portion, with the extended portion extending in a direction crossing a projecting direction of the projection. The extended portion extends downstream in a rotational direction of the coupling member toward the projection.

A drum unit for a cartridge includes a cylindrical photosensitive drum having an axis L1, and a coupling member operatively connected to the photosensitive drum. The coupling member includes a drum flange provided at an end of the photosensitive drum with a part of the drum flange being positioned inside of the photosensitive drum. The drum unit also includes a connecting part operatively connected to the drum flange, with the connecting part including a cap positioned adjacent to the drum flange, an arm portion extending from the cap in a direction of the axis L1, and a projection projecting from the arm portion in a direction perpendicular to the axis L1. The arm and the projection are movable relative to the drum flange and the cap.

A cartridge includes a casing and a photosensitive drum rotatably supported by the casing. A coupling member is operatively connected to the photosensitive drum, with the coupling member being rotatable about a rotational axis thereof. The coupling member includes (i) a cylindrical portion, (ii) a first projection at least partially positioned inside of the cylindrical portion, (iii) a second projection at least partially positioned inside of the cylindrical portion, and (iv) an aligner at least partially positioned inside of the cylindrical portion, the aligner including a surface that faces the rotational axis. A distance between at least one of the first and second projections and the aligner is changeable.

A method of manufacturing a torsion bar is provided. The method includes cutting a stock torsion bar material to a desired torsion bar length to form the torsion bar. The method also includes forming a first end portion by removing material from the torsion bar to form a first annular groove extending circumferentially about the torsion bar. The method further includes forming a second end portion by removing material from the torsion bar to form a second annular groove extending circumferentially about the torsion bar.