Patent ID: 8360748

Claim:
A rotary piston machine which operates as a pump or a compressor, comprising: a pump drive device defining a can motor with a can and a power rotor which is toothed with a driven trochoid, a corresponding rotor which engages in the toothing and as a result is correspondingly toothed, a working space which is arranged between the rotors, a basic housing which holds parts for controlling the pump drive device, a pump head which supports the rotors axially and radially, and a releasable connecting device between the basic housing and the pump head, wherein the can includes a radially extending section between sides of the basic housing and pump head which face one another, wherein the pump drive device is divided by the can into a magnet part which is arranged in the power rotor and into a coil part which is arranged in the basic housing and through which current flows, wherein the can has a cup shape section that functions as a bearing for the power rotor and the can has a broad flange which is radially clamped in between the basic housing and the pump head; and wherein the power rotor has a bearing section arranged within the cup shape section of the can and has a permanent magnet.