公开(公告)号：EP1171713A4

公开(公告)日：2002-11-20

申请号：EP01910995

申请日：2001-02-20

申请人： CATERPILLAR INC

发明人： BLASS JAMES R ,  WEAR JERRY A ,  SOMMARS MARK F ,  GIBSON DENNIS H ,  MATTA GEORGE M

IPC分类号： F04B1/28 ,  F04B1/29 ,  F04B7/04 ,  F04B49/22 ,  F04B49/00

CPC分类号： F04B7/04 ,  F04B1/28 ,  F04B49/225 ,  F04B2201/06011 ,  F04B2205/05

摘要： A high pressure pump system (14) for use with a hydraulic engine system (10), such as a fuel injection system (10) or a compression release brake system, provides variable delivery of pressurized fluid using sleeve metering principles. The relative position of metering sleeves (56) with respect to pumping pistons (32) is controlled electro-hydraulically by a control circuit (60, 160). The control circuit (60, 160) receives pressurized fluid from the pump delivery gallery (50) or another high pressure area (50, 52) and, using a pressure reducer (64, 164), reduces the operating pressure within the control circuit (60, 160) to a substantially constant pressure lower than the pump output pressure. Lower operating pressure within the control circuit (60, 160) improves the manufacturability of the control circuit components and helps to achieve better control of the pump output.