Abstract: A rotary piston engine having a commutator valve in a cooperating connection with the output shaft so as to supply and remove pressure medium to and from tooth chambers. Said engine further comprises passages which end adjacent to the commutator valve in ellipse shaped control openings. The commutator valve is integrally formed with the output shaft and all control channels are in the outer circumference of the commutator valve in the form of grooves which are parallel to the axis. Lands are provided between said grooves. The width of the lands defining said grooves is selected such that the width of the lands changes alternately, one land having a width approximately corresponding to the smaller width of the control ellipse, while the alternate land has a width which is increased by an oversize over the width of the smaller width of said control ellipse.

Abstract: The present invention relates to a rotary piston machine comprising a housing which consists of a flange housing, an intermediate housing and an end housing. The flange housing has a flange extending there from landing the machine on a suitable support. A shaft is rotatively supported within the housing, and a rotor is fixedly mounted on the shaft and adapted to rotate together with the shaft. A hollow gear for farming compressing chambers is also located within the housing for cooperation with the rotor. A commutator is fixedly mounted within the flange housing means and is adapted to supply pressure medium to and to remove pressure medium from the compressing chambers.