Piston pump

摘要

The invention relates to a piston pump with a piston received axially displaceably in a pump bore. To improve the aspiration performance of the piston pump. A cuff with a U-shaped annular cross section is provided, the cuff is inserted into the pump bore surrounding the piston, an outer lip forms a diaphragm, which rests against a wall of the pump bore and is acted upon on its outside with ambient pressure through a venting bore. The cuff is part of a fluid storage element, which makes an additional fluid volume available to the piston pump. The diaphragm acted upon by ambient pressure creates a pumping effect, if a fluid pressure in the fluid storage element drops below ambient pressure in an intake stroke of the piston.