| 摘要 |
<p>PURPOSE:To increase the amount of operation without losses by throtting operation during the excavating work by a method in which load acting on a working machine is detected, and the area of opening on the meter-out side of the control valve of the working machine is controlled by the detected signals. CONSTITUTION:A pressure gauge 16 is connected to the bottom-side pipe 15 of an arm cylinder 8, and the detection output of the gauge 16 is compared with a judged pressure for a command flow rate. When the actual pressure is great and a working machine is in excavating state, the opening area of the meter-out side poppet valve 131 for lever command value stored in a memory is read out from straight line A1 when a map 21 is not throttled and sent out to an arm control valve 13 for increasing the amount of operations. When the actual output is small and the working machine is not in excavating state, the opening area is read out from the straight line A0 when the map 21 is throttled, control signal is sent out to the control valve 13 for preventing damping. The cylinder 8 can thus be operated by pressures when the poppet valve 131 of the control valve 13 is not throttled, eliminating the occurrence of losses.</p> |
