Patent ID: 8123500

Claim:
A diaphragm pump with two diaphragms disposed in a pump housing and adapted to act on a fluid medium to be pumped, the diaphragms each being actuated by a piston adapted to reciprocate between the diaphragms and upon both sides of which a pressurized medium can act alternately, the diaphragms being supported, respectively, in terminal areas of two piston rods connected to the piston, wherein each of the two diaphragms is clamped with a respective annular curvature and the annular curvatures are arranged to do a selected one of (1) face each other, and (2) face away from each other in opposite directions, wherein each annular curvatures has an external edge zone in a fixed location in the pump housing and an internal edge zone fixed on a respective disk that is fixed to a free end of a respective piston rod, wherein the annular curvatures of the diaphragm are not reversed nor flattened during operation of the pump; wherein two reaction spaces are formed between the diaphragms and a cylinder housing the piston, wherein the reaction spaces are connected together by means of hydraulic conduits in communication with the reaction spaces, and wherein the reaction spaces and the hydraulic conduits are filled with hydraulic fluid and hermetically sealed; wherein in order to seal the reaction spaces internally, each reaction space is provided with a bellows fixed at one end to the cylinder and at an other end to the respective disk fixed to the free end of the respective piston rod associated with each reaction space; wherein each of the bellows encloses a space separated from a respective reaction space and wherein each space is in communication with a respective adjacent pressure space of the piston by means of a respective opening in the cylinder.