| 摘要 |
<p>An apparatus for indicating contamination degree for grasping the contamination degree of an oil in a hydraulic circuit and a determining method therefor, comprising a sensor which operates when a pressure difference between an inlet and an outlet of a filter provided in the circuit of hydraulic operation oil exceeds a predetermined value, and an indicator unit which operates upon receipt of a signal from the sensor, and wherein loading of the filter caused by contaminating substances in the hydraulic operation oil is indicated by detecting the pressure difference between the inlet and outlet of the filter and is controlled. For this purpose, two or more filters having dissimilar filtering particle sizes are arranged in the circuit, the pressure is detected at the inlet and outlet of the filters or the orifices, and a display unit is actuated at a portion where the pressure difference between the inlet and the outlet exceeds the predetermined value. Two or more filters are arranged in series in the order of decreasing filtering particle sizes, or the two or more filters are arranged in parallel by providing a distribution valve to divide the flow of operation oil into two. Being constituted as described above, foreign matter having large particle sizes that may cause hydraulic devices to be destroyed can be detected at an early time, and the contamination conditions of the whole operation oil can be grasped, making it possible to take a suitable measure such as preventing in advance the occurrence of any inconvenience in the hydraulic devices.</p> |
