CPC B65H 1/14 (2013.01) [B65H 1/04 (2013.01); B65H 2403/10 (2013.01); B65H 2403/481 (2013.01); B65H 2403/51 (2013.01)] | 11 Claims |
1. A drive transmission device comprising:
a cam portion configured to rotate about a rotation shaft;
a drive source configured to drive the rotation shaft to rotate the cam portion;
a cam follower configured to be in contact with the cam portion and move, by rotation of the cam portion, in a first direction to be close to the rotation shaft and in a second direction to be away from the rotation shaft; and
an extension spring configured to press the cam follower against the cam portion, wherein
the cam portion includes
a first cam defining a maximum distance between the cam follower and the rotation shaft and
a second cam having an inner edge portion positioned closer to the rotation shaft than an outer edge portion of the first cam, and
in a process of the cam follower moving in the second direction by the rotation of the cam portion, a portion of the cam portion, the portion being in contact with the cam follower, is switched from the second cam to the first cam,
wherein, a second friction coefficient, which is a coefficient of friction between the inner edge portion and the cam follower, is higher than a first friction coefficient, which is a coefficient of friction between the outer edge portion and the cam follower.
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