Patent ID: 7674100

Claim:
A pump comprising: a housing, a rotor path defined within the housing, an inlet formed in the housing at a first position on said rotor path, an outlet formed in the housing at a second position on said rotor path spaced from said first position, a rotor rotatable in said housing around an axis, the rotor having an outer surface which seals against said rotor path, and at least one chamber-forming concavity inwardly formed from said outer rotor surface, said concavity a) having a concave surface which is concave in planes including the rotor axis, b) being surrounded by said outer surface, and c) solely forming a conveying chamber travelling around said rotor path on rotation of the rotor to convey fluid around the housing; and a resilient seal carried by the housing, located on said rotor path and extending between the outlet and the inlet in the direction of rotation of said rotor, said resilient seal being adapted to seal with and be resiliently deformed by said outer surface surrounding said concavity to prevent fluid flow from said outlet to said inlet past the seal, and to seal with said concave surface of said concavity, as said concavity passes between the outlet and the inlet to squeeze fluid from the chamber into the outlet.