Photosensitive member unit, cartridge and electrophotographic image forming apparatus

A photosensitive member unit detachably mountable to a main assembly of an image forming apparatus, the photosensitive member unit comprising:

• a photosensitive member rotatable about a rotational axis thereof;
• a rotatable first helical gear portion;
• and
• a second helical gear portion integrally rotatable with the first helical gear portion, the second helical gear portion being provided between the photosensitive member and the first helical gear portion in a direction of the rotational axis of the photosensitive member,
• wherein a twisting direction of a tooth of the second helical gear portion is the same as a twisting direction of a tooth of the first helical gear portion, and a helix angle of the tooth of the second helical gear portion is greater than a helix angle of the tooth of the first helical gear portion.