Pedal crank for bicycle - has pedal fitted to sprung and pivoted extension lever engaging curved rod joined to crank end

摘要

The pedal crank is used on a standard bicycle to increase leverage during the driving effort. It comprises a crank arm fitted to the end is an extension lever (2), operation on a pivot (3) in the arm. This lever carries the pedal on its other end and its action is spring loaded (9). A threaded curved rod (8) is held in the pedal end of the lever. The other end (10 passes through a hole (7) in the crank arm (12), being free to move in accordance with the pedal action.