| 摘要 |
<p>PURPOSE:To make easier the fine operation of the valve requiring no confluence by a method in which necessary pilot pressure is only directed to the regulator of a variable capacity hydraulic pump for the valve group not controlled for confluence during the confluence control period. CONSTITUTION:Each switch valve group is driven by the first and second variable capacity hydraulic pumps P1 and P2, and each of switch valves is controlled by operating levers 14-19 by using a pilot hydraulic pump 13 and both the pumps P1 and P2 are controlled. The pilot pressures of pilot operating valves 14-19 are directed to the pump P1 or P2 through sequence valves 42 and 43. During concurrent operation of each switch valve group, the valves 42 and 43 are operated in a restorative manner by the pilot pressures. When controlled by confluence from both the valve groups, the fine operations of the valves for which confluence is not needed can be easily attained.</p> |
