Patent ID: 7682283
Filing Date: 2010-03-23
Classification: B62M,F16D,Y10T

Abstract:
1. A hub transmission for a bicycle comprising: a hub axle; a driver rotatably supported to the hub axle; a hub shell rotatably supported to the hub axle; a power transmitting mechanism disposed between the driver and the hub shell for communicating rotational power from the driver to the hub shell through a plurality of power transmission paths; a shift mechanism for selecting the plurality of power transmission paths; a shift assist mechanism for communicating rotational power from the driver to the shift mechanism; and a power control mechanism disposed between the driver and the shift assist mechanism and coupling rotational power from the driver to the shift assist mechanism for communicating rotational power from the driver to the shift mechanism to prevent locking between the driver and the shift mechanism when the shift assist mechanism engages the driver to communicate rotational power from the driver to the shift mechanism and the shift mechanism provides excessive resistance to the shift assist mechanism; wherein the power control mechanism is structured so that a magnitude of rotational power output from the power control mechanism varies by a non-constant coefficient relative to a magnitude of rotational power input to the power control mechanism as the driver rotates; and wherein the power control mechanism comprises: