Patent ID: 6032968
Filing Date: 2000-03-07
Classification: B62M

Abstract:
A bicycle having a drive mechanism, a frame comprising of a seat tube, seat stay and chain stay, a pedal means for applying manual power to propel the bicycle, a drive wheel rotatably supported on the frame, and a drive mechanism connected to the pedal means for rotating the drive wheel, the drive mechanism comprising:a pump unit comprising a pump housing, a first gear assembly operationally disposed within said pump housing and driven by the rotation of the pedal means outside of said pump housing, said pump unit outwardly adjacent the seat tube and the chain stay;a hydraulic motor being supported on the frame, said hydraulic motor comprising a motor housing and a second gear assembly operationally disposed within said motor housing, said second gear assembly adapted to engage the drive wheel, said hydraulic motor outwardly adjacent the seat stay and the chain stay and driven by the hydraulic fluid pumped by said pump unit, said pump unit and said hydraulic motor having a rotary motion relationship in the range of approximately 2.5:1 up to approximately 18:1;conduit means coupled between said hydraulic motor and said pump unit for circulating hydraulic fluid through said pump unit and said hydraulic motor, said conduit means creating a closed hydraulic system;pressure regulator means in said closed hydraulic system for controlling the quantity of hydraulic fluid transmitted to said hydraulic motor when the pedal means is rotated;a hydraulic fluid reservoir disposed above said pump unit, said conduit means coupled to and in fluid communication with said reservoir; andsaid second gear assembly comprising a smaller pinion gear and a larger idle gear in rotational meshing contact with one another, said smaller pinion gear driving the drive wheel.