| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To continuously provide predetermined sealability by preventing wear of a valve of a pump. <P>SOLUTION: The piston pump is equipped with an output valve 6 permitting flow of fluid from a pump chamber 4 to a discharge passage 15. The discharge passage 15 communicates with the pump chamber 4 through a communicating path 23 formed between the inner peripheral face of a plug hole 11 and the outer peripheral face of a plug 2. The output valve 6 is formed to be ring-shaped by an elastic body and positioned in the communicating path 23. The output valve 6 is structured to elastically deform and open the communicating path 23 when pressure in the pump chamber 4 is higher than that of the discharge passage 15. Wear of the output valve 6 can be prevented and the predetermined sealability can be continued because the output valve 6 slides with neither a housing 1 nor the plug 2. <P>COPYRIGHT: (C)2004,JPO</p> |
