Pedal crank for vehicle has cam in crank axis to alter length of crank arms on power stroke

摘要

The pedal crank for a vehicle has the length of the crank arms altered during their use when the pedal is descending to multiple the force applied. The crank arms (c) can slide (b) in the crank axis shaft (a) under the action of a cam (d) to significantly increase the length during the downward stroke. The length change is limited to accommodate user ergonomics.