Patent ID: 6640662
Filing Date: 2003-11-04
Classification: B62M,Y10T

Abstract:
A variable length crank arm assembly for a bicycle having a frame and a rotatable spindle, the crank arm assembly comprising,a crank arm coupled to the spindle for rotation about the spindle, the crank arm having a longitudinal axis, the crank arm having a proximal stop adjacent the spindle and a distal stop distally from said spindle; a slide mounted upon said crank arm for slideable movement thereon between a proximal location proximal the spindle and a distal location distal the spindle; a pedal rotatably mounted to said slide; a first spring mounted between said slide and said proximal stop to bias said slide toward said distal stop along said crank arm longitudinal axis; and a second spring mounted between said slide and said distal stop to bias said slide toward said proximal stop along said crank arm longitudinal axis, whereby an operator may force the slide along the crank arm against the biasing force of the second spring to elongate a stroke of the variable length crank arm and then allow the biasing force of the second spring to return the slide toward the proximal stop, and whereby the operator may force the slide along the crank arm against the biasing force of the first spring to shorten the stroke of the variable length crank arm and then allow the biasing force of the first spring to return the slide toward the distal stop.