Hydraulic piston pump noise reduction - involves pressure and pump speed controlled throttle valve in duct connecting adjoining cylinders

摘要

The arrangement is intended for reducing noise generated by a hydraulic piston unit particularly a piston pump having a number of cylinders (2) in a cylinder block (1) by reducing the rate of pressure increase in each individual cylinder. This is effected by a valve (8 11) which is controlled as a function of both pressure and pump speed. The adjoining cylinders of cylinder pairs may be connected by ducts (10) containing throttles which may consist of a controlled valve (8 11). The valve may be a spring-loaded (12) piston valve (11) in a chamber (8) arranged in the duct (10).