Patent ID: 7766635

Claim:
A rotary pump comprising: a housing ( 1 ) defining a working room in a shape of two intersecting cylinder sections ( 2 , 3 ), inlet and outlet ports ( 4 , 5 ) on mutually opposite sides of the housing ( 1 ), and in each cylinder section ( 2 , 3 ) one of two rotors ( 6 , 7 ), each rotor ( 6 , 7 ) being rotatably disposed about its center longitudinal axis ( 8 , 9 ) and having a major and a minor transverse axis ( 15 , 16 ) and further having two approximately club-shaped sections that are connected to each other at their narrower ends via a waisting, the rotors ( 6 , 7 ) having a configuration and being disposed relative to each other such that when the major transverse axes of the two rotors ( 6 , 7 ) are positioned perpendicular to each other, the club-shaped section of one rotor ( 6 , 7 ) engages into the waisting of the other rotor ( 6 , 7 ), wherein the rotors ( 6 , 7 ) roll off on one another and against the interior wall of the housing ( 1 ) in a sealing manner creating in each phase of the rotation movement an evenly increasing intake volume in front of the inlet port ( 4 ) and an evenly decreasing discharge volume in front of the outlet port ( 5 ), each rotor ( 6 , 7 ), when viewed along its center longitudinal axis ( 8 , 9 ), is helically twisted about the longitudinal axis, such that sealing lines ( 12 ) are created on an outer surface of each rotor ( 6 , 7 ) that extend sinusoidally, wherein the rotors ( 6 , 7 ) engage each other via the corresponding sealing lines ( 12 ) at their surfaces which are sinusoidally shaped, wherein said inlet and outlet port ( 4 , 5 ) comprising legs or lateral edges ( 17 , 18 ) and being triangular or trapezoidal shaped, said legs or lateral edges ( 17 , 18 ) of the inlet and outlet port ( 4 , 5 ) are respectively configured to be sine and cosine shaped.