Patent ID: 6081767
Filing Date: 2000-06-27
Classification: F15B

Abstract:
A method for determining the amount of undissolved gas in a hydraulic medium of a hydraulic system, the hydraulic system having valves and actuators contained in a low pressure section and a high pressure section, the method comprising:supplying the hydraulic medium to the low pressure section of the hydraulic system;supplying hydraulic medium to the high pressure section of the hydraulic system, wherein the hydraulic medium supplied to the low and high pressure sections of the hydraulic system has a pressure greater than the pressure of the high pressure section of the hydraulic system, wherein the hydraulic medium has a volume flow per unit time (V) parameter and a pressure (P) parameter;holding either the volume flow per unit time (V) parameter or the pressure (P) parameter of the hydraulic medium constant while supplying the hydraulic medium to the hydraulic system;recording the variation of the non-constant parameter of the hydraulic medium while supplying the hydraulic medium to the low and high pressure sections of the hydraulic system;operating the valves and actuators of the hydraulic system in a predetermined sequence while supplying the hydraulic medium to the low and high pressure sections of the hydraulic system; andcomparing the recorded variation of the non-constant parameter of the hydraulic medium with data of a reference hydraulic system having a known amount of undissolved gas and subjected to the same predetermined operating sequence and operating conditions for determining the amount of undissolved gas in the hydraulic system.