Patent ID: 7938057
Filing Date: 2011-05-10
Classification: B60T,F04B

Abstract:
1. A piston pump for pumping a fluid, comprising: a cylinder, a piston disposed movably within an inner bore of the cylinder, a pressure chamber disposed in the inner bore of the cylinder, an inlet valve attached to an end of the piston facing the pressure chamber, a restoring element for the piston, and a drive mechanism for moving the piston in the cylinder, the drive mechanism moving the piston between a bottom dead center and a top dead center, wherein the pressure chamber has a first region with a first inside diameter and a second region with a second inside diameter, the first inside diameter being greater than the second inside diameter, and wherein the piston, as it moves from bottom dead center to top dead center, at least partially immerses the inlet valve into the second region of the pressure chamber having the smaller inside diameter.