Patent ID: 8568114

Claim:
A reciprocating pump having: a pump body comprising a suction path for a to-be-transported fluid, a discharge path for a to-be-transported fluid and respective end portions; a pair of diaphragms which are airtightly fixed to respective ones of said end portions of said pump body, and which are placed opposite to one another to form closed spaces with respect to said pump body respectively; pump shafts which are attached to said tip end portions of said diaphragms; a pair of pump flanges which slidably support said pump shafts, and which are located at respective ends of said pump body and are integrated with said pump body through connection bodies that are placed outside said diaphragms, each of said pump flanges include large diameter holes at a plurality of locations; connecting rods which connect connecting plates, attached to passing projecting portions that are outward projected from said pump flanges in said pump shafts, to each other in a state where said connecting rods are passed through said pump flanges to be placed outside said diaphragms; and a cover cylinder for each connecting rod which surrounds its respective connecting rod in a state where said cover cylinder is disposed between said pair of pump flanges; wherein slide bearings are associated with each connecting rod and are mounted in the large diameter holes in said pump flange, each slide bearing having a stepped shape including a small diameter portion, which is press-fitted into an end of the cover cylinder, and a large diameter portion, which has the same outside diameter as the cover cylinder; and wherein said connecting rods are slidably supported through said slide bearings which are supported by said pump flanges.