Patent ID: 6352017
Filing Date: 2002-03-05
Classification: F04B

Abstract:
A hydraulic pump comprising:a case having a plurality of fluid paths and a cylinder-shaped groove with a shaft-bearing hole; a shaft received in the shaft-bearing hole of the groove such that the shaft is rotatable; a cylinder block disposed in the groove of the case and having a plurality of cylinders, the cylinder block being rotated upon receipt of a rotational power of the shaft and the cylinder block having a barrel-shaped bottom portion surrounding the shaft; a piston received in each of the cylinders for reciprocating movement therein; a swash plate associated with the case such that the swash plate covers an opening portion of the groove, the swash plate having an inclined surface facing the cylinder block; a shoe associated with each piston, each shoe having a top side, a bottom side and a stepped middle portion, the top side of each shoe being connected to the piston via a connecting member and the bottom side of the shoe contacting the inclined side of the swash plate; and an elastic shoe holder having a base with a center hole through which the shaft extends and engaging the barrel-shaped bottom portion of the cylinder block and a plurality of separate shoe-holding parts, one for each shoe that are branched from the base while being spaced apart from each other with a predetermined distance for each shoe, each shoe holding part engaging the stepped middle portion of the shoe and biasing the shoe against the inclined side of the swash plate.