PRESSURE CONTROLLER FOR OIL-PRESSURE CIRCUIT

摘要

PURPOSE:To permit the recovery of power to a prime mover even when an oil- pressure motor does a pumping work by computing the command value of the tilting amount of a swash plate on the basis of the circuit pressure and the lever operating amount in order to control the tilting amount of the swash plate. CONSTITUTION:In a controller 12, a pressure control circuit 13 serves to compute the command value X of the tilting amount of a swash plate in response to the signal XL of lever operating amount from the operating amount detector 15a of an operating lever 15 and also to the signal P of circuit pressure from a pressure detector 17 detecting any one of circuit pressures Pa and Pb in the form of an electric signal through check valves 16a and 16b leading to the main circuit. A swash plate tilting amount control circuit 14 compares the command signal X with the signal Y of the tilting amount of swash plate from a pump swash plate tilting amount detector 18 provided to a push-away capacity operating mechanism 2a, and then sends out an operating current i for lessening the difference between both to a servo valve 10.