Exercise bicycle

DETAILED DESCRIPTION The main objective of the present invention is to provide an exercise bicycle with a novel transmission system which can overcome the drawbacks commonly associated with the prior art.
More specifically, the objective of the present invention is to provide an exercise bicycle in which the foot pedal cranks are not connected eccentrically to a drive shaft and in which rotation of the foot pedal cranks can be prevented when the reciprocating arm levers are oscillated.
Accordingly, the exercise bicycle of the present invention includes a frame with a front end portion and a rear end portion, a seat mounted on the frame, a foot pedal assembly including a pair of foot pedal cranks, a resistance wheel having an axle mounted rotatably on the front end portion of the frame, a transmission system to link the foot pedal assembly to the resistance wheel, and a reciprocating arm assembly including a pair of reciprocating arm levers mounted pivotally on the front end portion of the frame.
The transmission system includes: a first drive shaft mounted rotatably on the rear end portion of the frame, the foot pedal cranks being mounted on two ends of the first drive shaft; a second drive shaft mounted rotatably on the frame between the front and rear end portions; a one-way clutch including an inner wheel with an inner periphery and an outer periphery, the inner wheel being secured on the second drive shaft, an outer wheel with an inner periphery and an outer periphery formed with sprocket teeth, and a ratchet-and-pawl unit formed on the outer periphery of the inner wheel and the inner periphery of the outer wheel; a third drive shaft mounted rotatably on the frame between the front and rear end portions of the frame; a first sprocket mounted securely on the first drive shaft; second and third sprockets mounted securely on the second drive shaft; a fourth sprocket mounted securely on the third drive shaft; a fifth sprocket mounted securely on the axle of the resistance wheel; a first drive chain trained between the first sprocket and the outer wheel of the one-way clutch; a second drive chain trained between the second and fifth sprockets; and a third drive chain trained between the third and fourth sprockets