Radial plunger type pump with counter weight and washer integrally secured

A radial plunger type pump comprising:

• a housing;
• an eccentric cam shaft rotatably supported by the housing;
• a pair of bearing means for supporting the cam shaft in the housing;
• a radial plunger reciprocally disposed in a cylinder of the housing and reciprocating within the cylinder of the housing in accordance with the eccentric rotation of a cam portion of the eccentric cam shaft;
• a pair of counterweights disposed in spaces provided between the bearing means and the cam portion of the eccentric cam shaft, the pair of counterweights including a counterweight portion for balancing the rotation of the eccentric cam shaft and a washer portion for preventing the plunger from axial movement, wherein the counterweight portion and washer portion are integrally secured, wherein the counterweights are engaged with the eccentric cam shaft for preventing the relative rotation therewith, wherein the pair of counterweights have an engaging portion which engages with the eccentric cam shaft for preventing the relative rotation therewith, wherein the engaging portions of the pair of counterweights are radial projections provided in central bores and wherein the radial projections engage with grooved portions provided on the outer surface of the eccentric cam shaft for preventing the relative rotation therewith.