Patent ID: 8414276

Claim:
A piston pump for a vehicle brake system, comprising: a housing; a receiving element for receiving an inlet valve, the receiving element being positioned in the housing; a sealing ring positioned in the housing, the sealing ring adjoining the receiving element and configured to contact an interior surface of the housing, and the sealing ring (i) defining an inner surface, and (ii) having a radially extending snap lug defining a circumferential groove defined by the inner surface; and a piston rod positioned in the housing, the piston rod adjoining the sealing ring, wherein the piston rod has a first piston end defining a valve seat and a second piston end defining a contact surface configured to contact an eccentric element of an eccentric drive, wherein the piston rod includes (i) a first piston rod element that includes the first piston end, and (ii) a second piston rod element that includes the second piston end, wherein the first piston rod element defines an interior space configured to receive a portion of the second piston rod element therein, wherein the first piston rod element further includes a radially extending shoulder disposed between the first piston end and the second piston end, wherein the sealing ring is formed in one piece with the receiving element, and wherein the shoulder engages the snap lug within the groove to provide a snap connection between the sealing ring and the piston rod for premounting the piston rod on the sealing ring.