VARIABLE DISPLACEMENT LUBRICANT PUMP

摘要

A variable displacement lubricant pump includes a first plunger which pushes a shiftable control ring into a high pumping volume direction. A pump rotor comprises radially slidable vanes which rotate in the control ring. A pressure control system comprises a first pressure control chamber wherein a first plunger is axially moveable. A first pressure conduit connects a pump outlet port with the first pressure control chamber. A first pressure control valve controls a pressure in the first pressure control chamber. A second pressure control valve between an outlet opening in a side wall of the first pressure control chamber and a low pressure source controls the outlet opening and is a centrifugal valve mechanically connected with the pump rotor which closes at a high rotational speed of the pump rotor. The outlet opening is closed by the first plunger in a low pumping volume position and opened in a high pumping volume position.