ABNORMALITY SENSING METHOD FOR PRESSURE LIQUID TANK

摘要

PURPOSE:To have abnormality diagnosis earlier than in a conventional arrangement by sensing the oil pressure and surface level in a pressure oil tank at all times and by making judgement of abnormality by reference to the allowable range of the oil pressure/surface level curve in accordance with the polytrope change characteristic. CONSTITUTION:The oil pressure/surface level curve is stored in an operational control device 7 and compared with the condition of oil pressure and surface level in the pressure oil tank 1 sensed by an oil pressure sensor 5 and a surface level sensor 6. That it, abnormality is sensed by judging if the oil pressure PN sensed lies between Pmax and Pmin as upper limit Y1 and lower limit Y2 of the oil pressure/surface level curve for the sensed surface level concerned HN.