Driving force auxiliary device

A driving force auxiliary device for combining a manpower drive force and a motor drive force comprising a manpower drive means, an auxiliary power drive means, and a leg power detecting means, characterized in that:

• said manpower drive means includes
• a first rotor which is coaxially disposed on an outer periphery of a crank shaft and provided with a first one-way clutch to receive a turning force in a forward direction of said crank shaft,
• a second rotor which is coaxially disposed to freely rotate on the outer periphery of said crank shaft,
• an elastic body which is fitted between said first rotor and said second rotor to transmit a turning force of said first rotor to the second rotor, and
• an output gear which receives a turning force of said second rotor;
• said auxiliary power drive means includes
• a motor,
• a speed reducing gear train for reducing the motor drive force of said motor, and
• a third rotor which is coaxially disposed to freely rotate on the outer periphery of said crank shaft, and has an outer periphery teeth engaged with a final gear of said speed reducing gear train and a second one-way clutch disposed on an inner periphery thereof to transmit only a turning force in the forward direction of said final gear to said second rotor;
• and
• said leg power detecting means includes
• a first rotor member fixed to an outer periphery of said first rotor,
• a second rotor member fixed to an outer periphery of said second rotor,
• a pair of first and second bevel gears which is interconnected with said first and second rotor members respectively,
• a third bevel gear which is fitted to be engaged between said pair of first and second bevel gears,
• an output shaft which takes out a change in rotation of a supporting shaft for supporting said third bevel gear with respect to said pair of first and second bevel gears as a difference in motion between said first and second bevel gears, and
• a sensor connected to said output shaft.