Hydraulic system for hydraulic operators

A hydraulic system for hydraulic operating machinery for delivering pressurized fluid to a blower drive means and to a hydraulic operator circuit, comprising a variable displacement pump an-d control valves connecting said pump to said operator circuit and to said blower drive means, further comprising a temperature responsive pressure valve which is arranged in a control pressure line extending between the blower drive means and the respective control valve, said pressure valve setting a control pressure therein proportional to the temperature, wherein the control pressure line is connected to the blower drive means control valve in a sense to open it, characterized in that a control pressure valve is arranged between the control pressure line and a reservoir which control pressure valve is switched from a blocking position into a throttling position by a load pressure of the operator circuit when the operator circuit is actuated, in which throttling position the control pressure is diminished to a value for adjusting the blower drive means control valve such that a minimum speed of the blower drive means is set independent of the operator load, and comprising a regulator for the variable displacement pump which regulator receives through a load sensing line the higher of said load pressure or said control pressure.