A rotor comprises a central body configured to rotate. A lobe extends perpendicularly from the central body along an lobe axis. A curved leading periphery and a curved trailing periphery are on opposite sides of the lobe axis. A V-shaped rib spans between the curved leading periphery and the curved trailing periphery. A first hollow space is bounded by the V-shaped rib, the curved leading periphery, and the curved trailing periphery. The first hollow space is distal with respect to the central body along the lobe axis. A second hollow space is bounded by the V-shaped rib, the central body, the curved leading periphery, and the curved trailing periphery. The second hollow space is proximal with respect to the central body along the lobe axis. The rotor can comprise a plurality of stacked, stamped sheets to form a helically twisted supercharger rotor.

The invention relates to a metering pump (1) made of plastic, with two rotors (10) coupled to one another via gears (11) and drivable in opposite directions, which are seated in a pump housing (5) equipped with suction ports (6) and outlet ports (7), wherein each rotor (10) has a rotor shaft (12), the rotor shaft ends (15) of which are seated in the walls (8, 4) of the pump housing (5). Each rotor (10) has two rotor blade walls (13) arranged diametrically on the rotor shaft (12), a partially cylindrical rotor blade shoe (14) being formed at each of the peripheral ends of said rotor blade walls, wherein the rotor blade shoes (14) on the one hand contact the cylindrical inside wall regions of the pump housing (5) and on the other contact the rotor blade shafts (13) of the adjacent rotor (10) in a sliding and sealing manner.

The invention relates to a metering pump (1) made of plastic, with two rotors (10) coupled to one another via gears (11) and drivable in opposite directions, which are seated in a pump housing (5) equipped with suction ports (6) and outlet ports (7), wherein each rotor (10) has a rotor shaft (12), the rotor shaft ends (15) of which are seated in the walls (8, 4) of the pump housing (5). Each rotor (10) has two rotor blade walls (13) arranged diametrically on the rotor shaft (12), a partially cylindrical rotor blade shoe (14) being formed at each of the peripheral ends of said rotor blade walls, wherein the rotor blade shoes (14) on the one hand contact the cylindrical inside wall regions of the pump housing (5) and on the other contact the rotor blade shafts (13) of the adjacent rotor (10) in a sliding and sealing manner.

A multi-stage vacuum pump may include first and second half-shell components defining a plurality of pumping chambers and for assembly together along respective longitudinal extending faces; first and second end stator components for assembly at respective longitudinal seals for sealing between the first and second half-shell stator components when assembled together at the longitudinally extending faces; and annular seals for sealing between the first and second end stator components and the first and second half-shell stator components when assembled; wherein the longitudinal seals have end portions which abut against the annular seals for sealing therebetween and the first and second half-shell stator components have formations for resisting movement of the end portions away from the annular seals when the end portions are compressed between the first and second half-shell stator components.

A pump particularly for pumping abrasive and/or chemically aggressive liquids includes at least one rotating pumping member having a respective shaft, the at least one rotating pumping member being at least partially housed inside a pump body. The shaft is rotatably supported by at least one support associated with the pump body. The shaft and the at least one support are both at least partially made of a material having a hardness greater than or equal to 5 Mohs, where the material having a hardness greater than or equal to 5 Mohs is located at least in the areas of the shaft and of the support in mutual contact.