LOW NOISE CONTROL ALGORITHM FOR HYDRAULIC SYSTEMS

摘要

A hydraulic pump radiant noise reduction method for a forklift or other work machine is disclosed. The method includes initiating a noise control algorithm that is enabled during periods when the displacement of the hydraulic pump remains in the zero displacement position and an operator is not demanding flow from any of the hydraulic branch circuits. When the noise control algorithm is enabled, the control valve assembly associated with the hydraulic branch circuit having the lowest hydraulic fluid pressure in relation to the hydraulic fluid pressures of all other hydraulic branch circuits is opened while the remaining control valve assemblies are in held or placed in a closed position. In an alternative embodiment, a drain valve assembly is provided that is opened when the noise control algorithm is activated.

主权项

1. A hydraulic pump radiant noise reduction method including the steps of:
(a) providing a hydraulic system having a variable displacement pump in selective fluid communication with a plurality of hydraulic branch circuits, each of the hydraulic branch circuits having a control valve assembly and containing hydraulic fluid at a hydraulic fluid pressure; (b) determining that the pump displacement is in a zero displacement position and that an operator is not demanding flow from any of the hydraulic branch circuits; (c) initiating a noise control algorithm that is enabled as long as the pump displacement remains in the zero displacement position and an operator is not demanding flow from any of the hydraulic branch circuits; and (d) the noise control algorithm including, opening the control valve assembly associated with the hydraulic branch circuit having the lowest hydraulic fluid pressure in relation to the hydraulic fluid pressures of all other hydraulic branch circuits while ensuring that all remaining control valve assemblies are in a closed position.