Hydraulic pump and improved by-pass flow means therefor

摘要

A hydraulic pump is disclosed of the type including a by-pass valve to limit the fluid volume output of the pump. The by-pass valve is disposed within a portion of the pump housing which extends axially into the fluid reservoir and defines a pair of by-pass ports. The pump is preferably balanced and includes a pair of diametrically opposed inlet kidney ports. A tubular member is used to direct a portion of the by-pass fluid from each of the by-pass ports toward the adjacent inlet kidney. Each of the tubular members is disposed to direct the by-pass flow axially into the inlet kidney, thus improving filling of the pumping pockets, and reducing cavitation and the resultant noise.