DRIVE TRANSMISSION APPARATUS AND IMAGE FORMING APPARATUS

摘要

A drive transmission apparatus in which, when immobilization of a preceding gear (21) by a solenoid (22) is canceled, an urging portion urges the preceding gear (21) to rotate in a direction in which the preceding gear (21) meshes with an input gear (24) which rotates at a constant velocity. An interlocking portion causes an output gear (20) to mesh with the input gear (24) in association with the rotation of the preceding gear (21), to rotate the output gear (20) at a low velocity, and to rotate the output gear (20) at a high velocity when the output gear (20) rotates by a predetermined amount.

主权项

1. A drive transmission apparatus, comprising:
a drive gear having a first drive gear and a second drive gear, the drive gear being driven by a drive source to rotate at a constant velocity; an output gear having a first output gear which has a toothless portion and is configured to mesh with the first drive gear, and a second output gear which has a toothless portion and is configured to mesh with the second drive gear; a preceding gear having a first preceding gear which has a toothless portion and is configured to mesh with the first drive gear, and a second preceding gear which has a toothless portion and is configured to mesh with the second drive gear; a preceding gear regulating portion configured to regulate rotation of the preceding gear; an urging portion configured to urge the preceding gear to mesh with the drive gear; and an interlocking portion configured to integrally rotate the output gear in association with the rotation of the preceding gear so that the output gear meshes with the drive gear, wherein the drive gear, the preceding gear, and the output gear are configured in a manner that: the second preceding gear meshes with the second drive gear when regulation of the rotation of the preceding gear by the preceding gear regulating portion is canceled and the urging portion urges the preceding gear to rotate, and the second output gear meshes with the second drive gear when the interlocking portion rotates the output gear integrally with the preceding gear so that the output gear rotates at a first velocity; and when the second output gear then terminates a meshing relationship with the second drive gear, the first output gear meshes with the first drive gear so that the output gear rotates at a second velocity.