Patent ID: 8590655

Claim:
A pedal driven apparatus comprising: manually operable pedals fixed for rotation with a pedal spindle for receiving a manually provided driving force; a motor having a motor shaft for receiving a motor provided driving force; wherein the motor is arranged concentrically around the pedal spindle such that the pedal spindle is freely accommodated through a hollow bore of the motor shaft, the motor shaft supported by a bearing on a casing of the pedal driven apparatus; the pedal spindle and the motor shaft sharing the same axis of rotation; a first torque transmission path for transferring the manually provided driving force to a sprocket of the pedal driven apparatus; a second torque transmission path for transferring the motor provided driving force to said sprocket of the pedal driven apparatus; wherein a first one way drive means is provided in the first torque transmission path between the pedal spindle and the sprocket such that when the sprocket is being driven by the motor provided driving force through the second torque transmission path, the pedal spindle is able to freewheel; wherein the second torque transmission path comprises the motor shaft and a gear mechanism mechanically coupling the motor shaft to the sprocket, wherein the gear mechanism has a reduction gear ratio and operates to transfer the motor provided driving force from the motor shaft to the sprocket at said reduction gear ratio; the gear mechanism comprises a planetary gear mechanism having a planet gear whose axis of rotation is offset by a predetermined amount with respect to the axis of rotation of the motor shaft; the planet gear being rotatably supported on an eccentric wheel whereby the planet gear is made to rotate as the eccentric wheel rotates and whereby the position of the axis of rotation of the planet gear changes relative to the axis of rotation of the motor shaft as the planet gear rotates such that the varying position of the axis of rotation of the planet gear defines a circle centered on the axis of rotation of the motor shaft, said circle having a radius equal to the predetermined amount.