Patent attributes
A motor pump unit with a multipart housing comprises a reversible internal gear machine and an electric motor with a rotor and a stator, which is coupled to the internal gear machine via a shaft rotatably mounted in the housing. One shaft end extends from the internal gear machine axially through the rotor that is carried by the shaft. First and second connecting channel ends in the working chamber of the internal gear machine are connected via check valves in the housing to a leakage channel loop, which is fluidically connected to a leakage channel that is fluidically connected to the working chamber, and which has a shaft leakage channel extending axially through the shaft and a rotor leakage channel that is fluidically connected thereto and extends axially through the rotor and/or a gap leakage channel between the rotor and stator, which is fluidically connected to the shaft leakage channel.