Planetary gearbox with integral service brake

摘要

A brake mechanism includes a fixed housing in which the brake mechanism substantially resides. A plate closes the fixed housing and includes a cylindrical portion extending partially within the fixed housing. A parking piston and a service piston are employed to act against a brake stack which includes a plurality of stators and rotors interleaved together. A wear adjuster is press-fit onto the cylindrical portion of the plate and engages the service piston during actuation of the service piston and compensates for wear of friction material from the rotors or stators such that the distance between the service piston and the brake stack is substantially the same during the life of the brake mechanism. If neither the service piston nor the parking piston engage the brake stack prohibiting rotation of the input drive, the planetary gear set drives the rotating output drive with respect to the fixed housing.