Patent ID: 8241020

Claim:
A piston pump, comprising: a piston having at least one transverse bore and one longitudinal blind bore; a plate element having an opening, the plate element being disposed on the piston at an orifice of the longitudinal blind bore; an inlet valve; an outlet valve; and a pressure chamber disposed between the inlet valve and the outlet valve, wherein the inlet valve includes a prestressing element, a closing element, and a sealing seat being formed on the plate element, wherein the inlet valve includes a retainer which retains the prestressing element of the inlet valve, wherein the retainer includes a sealing region which provides sealing at a cylinder and at the plate element, wherein the plate element includes a disk-like bottom region and an integrally formed annular collar which embraces an end of the piston toward the pressure chamber, and wherein the retaining device includes an annular extension which embraces the plate element, and the retaining device is fixed on the plate element.