| 摘要 |
<p>A capacity controller for a reversible and variable displacement hydraulic pump comprises an engine (1) the rotational speed of which varies in accordance with an amount at which a throttle pedal (4) is depressed, a reversible and variable displacement hydraulic pump (2) in which a discharge direction is changed when a swash plate (5) is turned from one side to the other side across its neutral position and in which its displacement varies as the turning angle of the swash plate changes, a controlling hydraulic pump (3) adapted to be driven by the engine and to change a flow rate in accordance with the engine rotational speed, a differential pressure generating circuit (47) having a restriction (48) for generating a differential pressure across the restriction according to a flow rate of pressure oil, a direction selector valve (40) for allowing pressure oil discharged from the controlling hydraulic pump to flow into the differential pressure generating circuit and/or stopping it from flowing, as well as controlling the flowing direction, and a servo controller (22) adapted to operate only an amount corresponding to a differential pressure across the restriction in the differential pressure generating circuit to thereby control the turning direction and angle of the swash plate.</p> |
