PUMPS

A rotary pump (200) comprises: a first fluid port (210) and a second fluid port (215); a housing (205) having an interior surface (220) defining a cavity in which a rotor (225) is located, the rotor comprising a housing engaging surface area (235) forming a sealing interference fit with the interior surface of the housing, and a surface recess (250) that forms with said interior surface of the housing a fluid-conveying chamber that, on rotation of the rotor, conveys fluid from the first fluid port to the second fluid port; a plurality of resiliently deformable diaphragms (255) providing part of the interior surface of the housing, each diaphragm comprising a rotor engaging surface (257) and a rear surface (260), the rotor engaging surface being urged into contact with the rotor by the action of a pressurising means (265) acting on the rear surface. The rotor comprises an elongate body that is substantially hollow, and a drive shaft (285), and comprises a first rotor cavity (270) and a second rotor cavity, the first rotor cavity (270) having an opening at a first end (240) of the rotor and the second rotor cavity having an opening at a second end (245) of the rotor. The rotor body further comprises a first opening between the first rotor cavity and the surface recess and a second opening between the surface recess and the second rotor cavity, the pump being arranged such that when the rotor body is located within the housing cavity, the first fluid port is in fluid flow communication with the first rotor cavity via the opening at the first end of the rotor, and the second fluid port is in fluid flow communication with the second rotor cavity via the opening at the second end of the rotor, and the pump being arranged such that the resiliently deformable diaphragm always bisects the first opening and the second opening on the rotor surface recess as the rotor rotates. Une pompe rotative (200) comprend : un premier orifice de fluide (210) et un second orifice de fluide (215) ; un boîtier (205) ayant une surface intérieure (220) définissant une cavité dans laquelle se trouve un rotor (225), le rotor comprenant une zone de surface de contact avec le boîtier (235) formant un ajustement avec serrage d'étanchéité avec la surface intérieure du boîtier, et un évidement de surface (250) qui forme avec ladite surface intérieure du boîtier une chambre de transport de fluide qui, lors de la rotation du rotor, transporte le fluide du premier orifice de fluide au second or