| 摘要 |
<p>PURPOSE:To make confluent or divert the delivery pressure oil of first and second pumps by means of one flow joining/dividing valve. CONSTITUTION:A hydraulic circuit comprises a confluence/diversion valve 2 for connecting the delivery passages 1a, 5a of a first pump 1 and a second pump 5 to the first and second main circuits 11, 12 respectively, a first pilot circuit 24 and a second pilot circuit 25 for detecting the load pressures of the operation valves which have been provided to a first main circuit and to a second main circuit respectively, an open/close valve 28 for communicating or cutting off the first pilot circuit and the second pilot circuit, and a shuttle valve 26 by which the pressures in the first and second pilot circuits are compared when the open/close valve 28 is in its open position for giving priority to the high-pressure side pressure. And also the hydraulic circuit is provided with a first unload valve 4 and a second unload valve 7 that have been provided to the delivery passages 1a and 5a of the first pump 1 and the second pump 5 respectively, and the confluence/diversion valve 2 is brought to the left confluence position or right confluence position from the diversion position by the pressure difference between the first and second pilot circuits 24, 25, and the pressure difference between the first and second main circuits 11, 12.</p> |
