Hydraulic fluid leak detection system and method

Abstract

A system such as one for detecting when a hydraulic fluid system adapted to a turf care machine, has developed a leak and to warn the machine operator of such a leak before an appreciable amount of hydraulic fluid is allowed to leak from the system. The system includes a reservoir for holding a quantity of hydraulic fluid. The reservoir is connected via a connecting tube or hose to an expansion tank mounted adjacent to the reservoir. The expansion tank includes a fitting having an elongated tube extending down into the expansion tank. The end of this tube is maintained substantially below the level of hydraulic fluid in the expansion tank during operation of the turf care machine to which it is attached. As the machine is operated, the hydraulic fluid expands with rising temperature, and the connecting tube communicates the expanding fluid to the expansion tank. When operation of the machine is discontinued the hydraulic fluid contracts as it cools. As the hydraulic fluid contracts, the hydraulic fluid in the expansion tank, is automatically drawn by a siphoning action through the elongated tube within the expansion tank through the connecting tube and back into the reservoir. A float type fluid level sensor is provided and mounted to measure the level of hydraulic fluid within the expansion tank. The float level sensor sends an electronic signal corresponding to the fluid level in the expansion tank to a microcomputer based monitoring unit. The monitoring unit also senses the fluid temperature and interprets these electronic signals and, compensating for volumetric fluctuations due to the changing fluid temperature, and determines if conditions exist which indicate a hydraulic fluid leak exists. If such conditions exist, the monitoring unit produces a warning signal which is communicated to the vehicle operator.