Self-calibrating hydraulic fluid leak detection system

Abstract

A hydraulic fluid lead detection system which self-calibrates for operation regardless of the particular reservoir or expansion tank. A reservoir stores a quantity of hydraulic fluid and is connected via a connecting tube or hose located at the upper-most portion of the reservoir and connected to an expansion tank mounted substantially adjacent to the reservoir. An elongated tube extends 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. During operation, the hydraulic fluid expands with rising temperatures, and the connecting tube communicates the expanding fluid to the expansion tank. A float type fluid level sensor measures the level of hydraulic fluid within the expansion tank and outputs an electronic signal corresponding to the fluid level in the expansion tank to the microcomputer based monitoring unit, which also senses the fluid temperature. The monitoring unit includes memory for storing a table of fluid temperatures versus fluid levels in the expansion tank stored during calibration of the system. During operation, the monitoring unit receives and interprets electronic signals from the float and temperature and compares the table values in memory to the values received from the float and temperature sensors to identify possible fluid leaks in the system.