Dosaging pump with pump bellows on bottles or the like

In a dosaging pump having a pump bellows and two valves, which is adapted to be placed on a container, in particular, bottles and the like, one of the valves being associated with a nozzle and the other with an inlet side, the improvement comprising

• a cup having a bottom and a surrounding wall, the latter surrounds said pump bellows,
• a cap engages over said pump bellows, said cap includes a cover, said cap has a side wall,
• said one valve comprises a nozzle-side valve-closure member which is seated in the cover of said cap, said side wall of said cap being guided on said surrounding wall of said cup,
• the other valve comprises an inlet-side valve-closure member, the latter being seated within the bottom of said cup,
• said bottom of said cup is formed with an air-inlet opening,
• said cup and said cap have collars,
• end folds of the pump bellows are seated on said separate collars of said cap, and said end folds extend into outwardly directed protruding base support rings, and
• a cup-bottom side of said base support rings has a sealing lip extending over said air-inlet opening in the cup bottom and said lip has a free-standing lip section resting against an inner wall of said cup.