Patent ID: 8229325

Claim:
A decelerator for reducing a speed of rotation of a drive source and transmitting drive of the drive source to an image bearing member of an image forming apparatus, comprising: a drive shaft to be rotated by the drive source; a drive transmission member rotated by the drive shaft, the drive transmission member including a peripheral surface that contacts the drive shaft; and a pressure regulator to press the drive shaft against the drive transmission member toward a center of rotation of the drive transmission member, the pressure regulator including an alignment regulator to regulate alignment of the drive shaft in a direction of rotation of the drive transmission member, wherein the alignment regulator is provided facing the peripheral surface of the drive transmission member, regulates alignment of the drive shaft, and contacts at least two locations of a periphery of the drive shaft opposite the surface facing peripheral surface of the drive transmission member, and wherein the alignment regulator includes two rollers that contact the drive shaft so as to follow rotation of the drive shaft.