| 摘要 |
<p>The invention relates to a bidirectional piston pump (2) controlling a working cylinder (1) or the like. Each end of the pump has two pipe fittings (7a, 7b; 8a, 8b) for the medium, and each pipe fitting has a unidirectional valve (10, 11, 12, 13). Along the length of the cylinder (3) there are further provided a first and a second pair of fittings (17a, b; 18a, b), and these are coupled individually to unidirectional valves at the respective ends. The pump piston (4) has such a length that with its whole stroke length it closes either the first pair of fittings or the second pair of fittings in order to produce the first or the second operating state (k1; k2). Thus, in the first operating state the bidirectional piston pump pumps medium in one direction and in the second operating state in the opposite direction.</p> |
