US Patent 7793562 Transmission and shift method

Transmissions in which the mechanical gear shift arrangements are replaced by electro-hydraulic operated shift mechanisms that have to be able to be neutralised positively to ensure a proper operation. An arrangement and method are provided to determine the position of the shift rail so a shift can be made only if the conditions are right. To prevent engagement of two shift members at the same time and consequent damage in case of electronic failure, mechanical safety features such as detents are included.