An electrophotographic photosensitive drum is for a process cartridge detachably
mountable to a main assembly of an electrophotographic image-forming apparatus.
The process cartridge includes a charging roller for electrically charging the
photosensitive drum and a developing roller for developing a latent image formed
on the drum. The drum includes a drum helical gear, mounted to one end of the cylinder,
for transmitting a rotational driving force to a transfer roller provided in a
main assembly, and for transmiting a rotational driving force to the charging roller
and the developing roller. A shaft portion is provided at a central portion of
the drum helical gear at a position where it is completely overlapped with teeth
of the drum helical gear with respect to a longitudinal direction of the cylinder.
A gap is provided between the teeth and a peripheral surface of the shaft portion.
