Simplified piston pump

摘要

A simplified piston pump which is featured in that the number of components for the assembling thereof can be minimized, that the assembling thereof can be simplified, and low in manufacturing cost thereof. This simplified piston pump comprises; a cylinder having at least one protrusion formed on the inner surface of a proximal end portion of said cylinder for preventing the piston from slipping out; and a piston shaft having a structure wherein the outer surface of the piston shaft is contacted with the inner surface of the cylinder to prevent the decentering of the piston shaft and wherein a groove is formed thereon to ensure the reciprocative movement of the piston.