Abstract: The external rotor of a single-rotation machine has engagement spaces, whose boundary faces in the inward direction form a widening, which is adjacent in an outer region radial thereto to parallel surfaces or surfaces forming a widening in the outward direction. The side walls axially bounding these engagement spaces have a radially outer part, which is cast in one piece with the peripheral parts of the external rotor and an inner part radial thereto, which subsequently reduces to a circular opening the opening surrounded by the radially outer parts, so that the radial seal between side walls and a stationary sealing member surrounded by said opening is located radially within the peripheral parts of the external rotor and a sealing gap in the radial plane between the peripheral parts and the sealing member is avoided.

Abstract: For an improved sealing at the sealing gaps of a single-rotation machine having internal axes and accompanied by minimum frictionally losses, the width of the sealing gaps is made to differ in such a way that the narrower sealing gaps occur on the radially outer circumferential surfaces of the internal rotor facing the engagement parts of the external rotor. The comparatively wider sealing gaps occur on the transition surfaces between radially inner circumferential surfaces and radially outer circumferential surfaces of the internal rotor.

Abstract: The engagement parts of the external rotor of a single-rotation machine having an internal axis with sealing between its rotors and with respect to the machine casing by sealing gaps, are manufactured as single parts and following reciprocal alignment are joined at their two ends to in each case one circular side part. Alignment takes place by engaging the cross-sectionally arcuate outer faces of the engagement parts on arcuate parts of an assembly cage and by dimensionally accurate assembly bodies engaging between the engagement parts. The method permits narrower sealing gaps for the machine and consequently an improved efficiency.

Abstract: A heat pump unit comprising a compressor and an expansion machine for respectively compressing and re-expanding a medium which circulates in a heating or cooling circuit. The power used for compressing this medium is at least partly recovered in the expansion machine and is used for driving the compressor. The compressor and the expansion machine are inner axle, intermeshing rotary piston engines which are arranged directly adjacent to one another on a common shaft. The inner side walls of the rotary engines are adjacent to each other and have cavities and thermal insulating means interposed between them and, while being interconnected, are fixedly connected on the one hand to the shaft and on the other hand with outer rotors. The shaft is rotatably journalled in eccentrics of inner rotors, which eccentrics are rigidly connected with a stationary housing.

Abstract: A pressure valve arranged in a rotary piston compressor which valve is mounted in a passage or bore of the housing casing of the compressor. The last mentioned passage is axis parallel to the rotary piston compressor axis. The valve has a cylindrical cross section and can be inserted into the passage or bore parallel to the compressor axis behind an outlet opening in the track of the housing casing through a side wall of the compressor. The valve seat is formed by a longitudinally slotted tubular part which exerts a radially outwardly directed resilient force. The slotted tubular part comprises segmental valve opening slots extending parallel to the side walls of the compressor. Over the slots are located valve lugs or tongues which are cut from a thin-walled tube arranged with a precise fit in the tubular part while the roots of the valve lugs or tongues are connected to the thin-walled tube. An additional tube is with precise fit inserted into the thin-walled tube.