Pumpenspender für Medien

摘要

The fluid pump dispenser has a pump body (2) including a pump cylinder defining a pump chamber (4) with a valve controlled product inlet passage leading to the chamber. A manually reciprocated pump plunger (12) having a hollow stem (22) defining a discharge passage leading from the chamber (4) is slide-mounted in the body. A pump piston (26) is mounted on the inner end of the stem (22) for relative sliding movement. A plunger return spring (13) biases the plunger (12) into a raised position. The piston (26) is limited for relative sliding movement between discharge open and closed positions. The piston has an annular projection defining a discharge valve seated in an annular groove of a plug element fixedly mounted to the stem (22) at its inner end. A lost-motion effect is created between the piston (26) and the stem (22) which closes the discharge valve during the pressure stroke and opens the discharge during the intake stroke.