Failure prediction system suitable for use in hydraulic system.

摘要

Disclosed herein is a failure prediction system suitable for use in a hydraulic system equipped with a hydraulic actuator (2) and a drive circuit (1, 3, 5) therefor. The failure prediction system comprises one or more sensor units (6, 18, 19) provided with at least one of the actuator and circuit or at least one element of their component members to sense at least one parameter, for example, the pressure or temperature of the working oil or the sliding speed of the rod of the actuator while the hydraulic system is driven; operational means (7, 16) adapted to determine the extent of accumulated reduction in service life of the actuator, circuit or element on the basis of one or more correlations pre-established for the actuator, circuit or element between values sensed by the sensor units and their corresponding extents of reduction in service life of the actuator, circuit or element; and output means (7, 16) adapted to output a value corresponding to the extent of accumulated reduction in service life determined by the operational means. Since the above failure prediction system permits to predict how soon the actuator, circuit or element would fail, it is possible to prevent it from actually undergoing failure. The hydraulic system can thus be used without breakdown or malfunction. This is certainly advantageous from the viewpoints of avoiding casualties and damages to surrounding structures and interruption of work. The above failure prediction system also permits to use each element of an actuator or drive circuit until very close to the end of its maximum service life. The failure prediction system is effective particularly for machine tools and construction machines.