摘要 |
<p>A variable displacement lubricant pump providing a pressurized lubricant for an engine includes a control ring. A pump housing comprises a pump rotor with radially slidable vanes which rotate in the control ring. A pressure control chamber pushes the control ring into a low pumping volume direction against a force of a flexible pretensioning element. The pressure control chamber is connected with a pump outlet port via a first pressure conduit. A pretension control unit adjusts discharge pressures of the pressurized lubricant. The pretension control unit comprises a pretension cylinder with a plunger and an outlet opening arranged in a cylinder wall. The plunger is axially moveable and supports the flexible pretensioning element to push the control ring into a high pumping volume direction. The pretension cylinder is connected with the pump outlet port via a second pressure conduit. The outlet opening is connectable to a low-pressure via an electrical pretension control valve.</p> |