Patent ID: 6931954

Claim:
A power transmission device for transmitting power from an input side to an output side, comprising: a pair of gear assemblies, each including one first gear having a circular shape and external teeth formed on a peripheral wall of the first gear with the circular shape so that the first gear in one of the gear assemblies engages the first gear in the other of the gear assemblies, one second gear having a circular shape and external teeth formed on a peripheral wall of the second gear with the circular shape, and a clutch mechanism situated between the first and second gears such that said first gear is connected to the second gear when the first gear rotates in one direction relative to the second gear, and said first gear is separated from the second gear when the first gear rotates in the other direction relative to the second gear, and an idle gear rotatably supported, and engaging the external teeth of the second gears of the gear assemblies.