US Patent 7681472 Bicycle shifter

A shifter for a bicycle transmission that includes a spring element that functions as a preloaded spring for cable-release operations and a detent pawl. The shifter also includes a housing having a detent contour, a cable spool for winding and unwinding a control cable thereon, and an actuator. The actuator includes a release element, a spring seat and a driver. The spring element includes a detent pawl, a base and a spool driver. The detent pawl is engageable with the detent contour to maintain the shifter in a current detent position. The base is supported by the spring seat and the spool driver is operatively engages and rotates the spool.