| 摘要 |
<p>A pump consists of a valve box (2) in which a valve chamber (1) inlet (6) and outlet (7) are each provided with a valve, and a reciprocating member in a cylinder that communicates with the valve chamber (1) of the valve box (2) to open the said valves. A pressure action chamber (5) is provided between the valve box (2) and the cylinder (12) and a pressure force member divides the pressure action chamber (5) into a valve chamber side and a cylinder side. On the cylinder side of the pressure action chamber (5) thus divided is an action medium that transmits to the pressure force member changes in the volume of the pressure action chamber produced by the action of the reciprocating member. A valve means consists of a concave valve seat (19) and a number of fluid passages (20) formed therein opening into the said concavity. Either the valve seat or the valve-piece (9) is formed of, or covered with, a hard resilient material, or one is formed of the hard resilient material and the other is covered with a hard resilient material. The valve seat (19) and valve-piece (9) may be made of wood.</p> |
