Hydraulic system thermal contraction compensation apparatus and method

摘要

An apparatus for compensating for fluid contraction in a hydraulic powered telescoping boom (110) includes a monitor (200) determining the elevation angle of the telescoping boom, a supply of hydraulic fluid, and a fluid control responsive to the monitor. The fluid control provides the hydraulic fluid from the supply to a hydraulic cylinder (130) controlling extension of the telescoping boom when the elevation angle exceeds a predetermined threshold angle to compensate for thermal contraction of hydraulic fluid and thus prevent uncommanded boom retraction. A method in accordance with the invention is also disclosed.