CPC B65H 5/025 (2013.01) [B65H 3/0669 (2013.01); G03G 15/0136 (2013.01); G03G 15/1615 (2013.01); B65H 2404/255 (2013.01); B65H 2404/262 (2013.01); B65H 2801/06 (2013.01)] | 9 Claims |
1. A drive unit comprising:
a drive source; and
a driving force transmitter configured to transmit a driving force of the drive source to an object to be driven;
the driving force transmitter including:
a plurality of rotators;
an endless belt stretched by the plurality of rotators;
a pressing member configured to press the endless belt to apply tension to the endless belt;
a first support shaft;
a first link member rotatable around the first support shaft and holding the pressing member;
a second support shaft;
a second link member rotatable around the second support shaft and pressing the first link member; and
a biasing member configured to bias the second link member to press the endless belt by the pressing member,
a relation of L1 to L2 satisfying
L1>L2, where
L1 denotes a distance between the second support shaft and a biasing position at which the biasing member biases the second link member, and
L2 denotes a distance between the second support shaft and a first pressing position at which the second link member presses the first link member,
a relation of L3 to L4 satisfying
L3>L4, where
L3 denotes a distance between the first support shaft and the pressing position at which the second link member presses the first link member, and
L4 denotes a distance between the first support shaft and a second pressing position at which the pressing member presses the endless belt.
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