| 摘要 |
<p>A manually operatable dosage pump comprising a cylinder, a piston movable therein between two end positions, and inlet and outlet passages communicating with the cylinder space and each containing a one-way valve or check valve. The piston is adapted to interrupt communication between said inlet and outlet passages in at least one of the end positions of the piston. Thus, a valve member mounted on the piston may cooperate with valve seats formed in a valve chamber axially aligned with the cylinder space.</p> |
