| 摘要 |
In a method for preventing the puncture of a load-sensing and pressure-compensating control system for a hydraulic crane when the hydraulic flow requested to the different functions of the crane exceeds the maximum hydraulic flow available, the values of control signals Q1-QN from a means for controlling the different crane functions are added up, and the resulting sum QP is compared with the maximum hydraulic flow Qmax available from a pump. Should the hydraulic flow requested by the control signals exceed the maximum hydraulic flow available, the control signals are scaled down so as to define a flow which falls below the maximum flow available, thus ensuring that a hydraulic flow is at all times supplied to all the crane functions. A device for implementing the method can take the shape of a program in a computer which receives the control signals from the control means and transmits output signals to a directional-control-valve block in the control system. |
