| 摘要 |
A finger-operated pump is provided with a pump chamber and a fixed supply conduit communicating with the pump chamber. A movable sealing conduit is adapted to slidably and sealingly engage the supply conduit in a telescoping relationship. A primary piston is operably disposed in the chamber and defines a discharge passage out of the pump chamber. A poppet having a primary valve means for occluding the discharge passage is biased against the primary piston by a spring. The poppet has a secondary valve means for occluding flow through the sealing conduit that engages the poppet through a lost motion arrangement which is defined in part by the spring and which permits a limited degree of relative movement between the poppet and the sealing conduit. |
