Abstract: A photosensitive drum assembly and a process cartridge and a process cartridge having an improved structure in which a protrusion for receiving a driving force transmitted from a main body of an image forming apparatus may not be easily worn or damaged. The photosensitive drum assembly that is capable of being combined with a driving shaft including a twisted hole with a non-circular cross-section having a plurality of corners, includes: a support disposed at one side of the photosensitive drum; and an insertion body disposed at one side of the support and including a plurality of protrusions that are capable of being inserted in the twisted hole, wherein at least portions of each of the plurality of protrusions based on a cross-section of each protrusion that is perpendicular to the driving shaft, closely contacts two side surfaces of the twisted hole that constitute one of the plurality of corners of the twisted hole, respectively.

Abstract: Provided is a photosensitive drum driving assembly, a photosensitive drum assembly, a process cartridge, and an image forming apparatus. The driving assembly including a supporting body and an engaging protrusion is connected to a drive shaft having a triangular twisted hole to transfer a rotary driving force from an image forming apparatus. The engaging protrusion twistedly protrudes to be inserted into the twisted hole, and includes three or more line contact portions on its cross-section perpendicular to the protrusion direction. The line contact portions are in line-contact with the surface of the twisted hole, and at least one portion of a surface formed by continuously joining the line-contact portions along the protrusion direction is a twisted contact-surface to receive the rotary driving force transferred by the drive shaft.

Abstract: A photosensitive drum assembly and a process cartridge and a process cartridge having an improved structure in which a protrusion for receiving a driving force transmitted from a main body of an image forming apparatus may not be easily worn or damaged. The photosensitive drum assembly that is capable of being combined with a driving shaft including a twisted hole with a non-circular cross-section having a plurality of corners, includes: a support disposed at one side of the photosensitive drum; and an insertion body disposed at one side of the support and including a plurality of protrusions that are capable of being inserted in the twisted hole, wherein at least portions of each of the plurality of protrusions based on a cross-section of each protrusion that is perpendicular to the driving shaft, closely contacts two side surfaces of the twisted hole that constitute one of the plurality of corners of the twisted hole, respectively.

Abstract: Provided is a photosensitive drum driving assembly, a photosensitive drum assembly, a process cartridge, and an image forming apparatus. The driving assembly including a supporting body and an engaging protrusion is connected to a drive shaft having a triangular twisted hole to transfer a rotary driving force from an image forming apparatus. The engaging protrusion twistedly protrudes to be inserted into the twisted hole, and includes three or more line contact portions on its cross-section perpendicular to the protrusion direction. The line contact portions are in line-contact with the surface of the twisted hole, and at least one portion of a surface formed by continuously joining the line-contact portions along the protrusion direction is a twisted contact-surface to receive the rotary driving force transferred by the drive shaft.