| 摘要 |
<p>A ston pump includes a cylinder (26) with a bore (27) receivre the piston (24). The piston (24) forms a central passage (34) leading to a variable volume chamber (42) and a check valve (40) is disposed in the central passage. In addition, the cylinder (26) includes a pair of ports (48, 50) which selectively communicate with the variable volume chamber (42). The pair of ports (48, 50) and the central passage (34) communicate a reservoir with the variable volume chamber (42).</p> |
