Park by Wire System for current Electric Drive Units

Park lock systems are safety critical units. Due to intellectual property rights and different transmission configurations, a large variety of park lock design exists in the market. Furthermore, many park lock designs are still manually actuated. A new mechanical park lock system will be presented which is actuated by wire. The system has been optimized for rotary actuators and is extraordinarily compact. In addition, it minimizes the contact stresses due to optimized geometries. Furthermore, the functional safety and diagnostic concept for park-by-wire park lock systems, exemplarily for this system, will be presented. This will be done in accordance to current multi speed power-shift EDU concepts, including FMEA, legal, requirements summary, safety goal definition and error detection mechanism.