| 摘要 |
A disposable plastic pump for dispensing liquids is disclosed which comprises two basic unitary, preferably all plastic, elements: a chamber forming body having an open outer end and an inner end in fluid communication with a liquid reservoir, and a piston formed to slidably fit into the chamber. The chamber forms two axially adjacent coaxial chambers, an inner chamber of one diameter and an outer chamber of a greater diameter. The piston comprises a stem on which is located two spaced flexing discs each sized to fit in and serving as a one-way valve in the inner chamber and outer chamber, respectively, permitting fluids to flow outwardly past each flexing disc. A sealing disc is located on the stem outwardly of the outermost flexing disc. A passageway is provided from an inlet on the piston between the outermost flexing disc and the sealing disc through which the dispensed liquid flow. |
