Patent attributes
A drive transmitting mechanism configured to rotate the photosensitive drum of a color copier has a driving shaft, a driven shaft, and first and second coupling members. The first coupling member has a projection extending in a diametrical direction. The first coupling member is attached to the driving shaft, with amount of freedom to oscillate in a direction intersecting at right angles to the lengthwise direction of the projection. The second coupling member has a recess in which the projection is fitted. The second coupling member is attached to the driven shaft, with amount of freedom to oscillate in the lengthwise direction of the recess. The first and second coupling members oscillate in the diametrical direction and slide on the contacting surface in a diametrical direction intersecting at right angles to the diametrical direction, thus suppressing the rotational speed change of the driven shaft, which results from the de-centering and declination between the driving shaft and the driven shaft.