| 摘要 |
PURPOSE:To prevent an engine from stopping by a method wherein flow rates and delivery pressures of each hydraulic pump are detected, the torque outputted is calculated arithmetically and flow rates of each hydraulic pump are controlled so that they do not exceed the rated torque. CONSTITUTION:The comparator 60 compares an input signal E with a set point signal Eo and when E>Eo, signals ea, eb are outputted. The arithmetic circuit 61 outputs an instruction signal for a pump flow rate shown when a torque is over the set point (E>Eo). When the signal is given, the maximum torque Tc that can be given per pump is operated to the rated torque To of an engine EN and a corresponding signal 1c is outputted and on the other hand, contact points 31a, 32a..., 3na are changed over to points 31b, 32b...3nb by the comparator output ea. And, the instruction signal 1c is given to electromagnetic hydrualic servo valves 71-7n and the flow rates of each hydraulic pump PM1-PMn are decreased to a value qc proportional to the instruction signal 1c. Accordingly the torque outputted T of the engine is equal to the rated toreuq To and the engine can be prevented from stopping. |
