Exercise bicycle for exercising arms and legs

Claim 1

An exercise bicycle comprising: a frame assembly including a base frame, a driven wheel frame fixed on a front portion of said base frame, and a seat frame fixed on a rear portion of said base frame; a foot operated drive assembly including a driving shaft journalled on said seat frame, a rear driving sprocket sleeved rigidly on an intermediate portion of said driving shaft, two crank arms respectively secured to two ends of said driving shaft, and two pedals secured to said respective crank arms; a hand operated drive assembly including a wheel axle journalled on said wheel frame, a front driving sprocket sleeved rigidly on said wheel axle, two swing arms secured to two opposite end portions of said wheel axle, and two hand operated swing levers mounted pivotally at their lower ends on said base frame, each of said levers including an upper lever portion, two parallel rods respectively secured to two sides of a lower end of said upper lever portion, and a lower lever portion secured to inner sides of lower ends of said rods so as to define a slide slot between said rods, each of said rods having an arcuated inner side portion, each of said swing arms having a crank pin member and including a sheave sleeved rotatably on said crank pin member, each of said sheaves having an annular groove of a generally V-shaped cross-section and inserted into said slide slot of corresponding said lever in such a manner that said annular groove engages with said arcuated inner side portions of said rods, so that said crank pin member can slide along said slide slot of said lever; a driven shaft assembly including a driven shaft journalled on said base frame between said driving shaft and said wheel axle, a foot driven sprocket sleeved rotatably on said driven shaft, clutch means for locking said foot driven sprocket on said driven shaft when said foot driven sprocket rotates in a predetermined direction, a foot driven chain trained on said rear driving sprocket and said foot driven sprocket, a hand driven sprocket sleeved rotatably on said driven shaft, clutch means for locking said hand driven sprocket on said driven shaft when said hand driven sprocket rotates in a predetermined direction, a hand driven chain trained on said front driving sprocket and said hand driven sprocket, and a rear pulley sleeved rigidly on said driven shaft; and a wheel assembly including a wheel hub sleeved rotatably on said wheel axle, a wheel sleeved rigidly on said wheel hub, a front pulley sleeved rigidly on said wheel hub, and an endless belt trained on said front pulley and said rear pulley; whereby, when said pedals are rotated in said predetermined direction, said driving shaft, rear driving sprocket, foot driven chain, foot driven sprocket, driven shaft, rear pulley, endless belt, front pulley, hub, and wheel are in turn rotated in said predetermined direction; when said levers are swung, said wheel axle, front driving sprocket, hand driven chain, hand driven sprocket, driven shaft, rear pulley, endless belt, front pulley, hub, and wheel are in turn rotated in said predetermined direction; and when a first torque is applied to said driven shaft through said foot driven sprocket by rotating said pedals in said predetermined direction, and when a second torque is applied to said driven shaft through said hand driven sprocket by swinging said levers, the sum of said first and second torques is output through said rear pulley.