Automotive variable mechanical lubricant pump

An automotive variable mechanical lubricant pump for providing a pressurized lubricant for an internal combustion engine, the automotive variable mechanical lubricant pump comprising:

• a control ring configured to be shiftable in a control ring sifting direction between a maximum eccentricity position and a minimum eccentricity position, the control ring comprising an outer control ring circumference which comprises an effective anti-spring hydraulic surface and a pro-spring hydraulic surface;
• a pump rotor comprising a plurality of slidable vanes which are configured to rotate in the control ring;
• a control ring preload spring configured to push the control ring into the maximum eccentricity position;
• a hydraulic pilot chamber configured to push the control ring into the minimum eccentricity position, the hydraulic pilot chamber being charged with a pump outlet pressure or with a gallery pressure of the internal combustion engine;
• a hydraulic pressure control circuit configured to control the gallery pressure by directly regulating a pilot chamber pressure;
• a pump outlet for the pressurized lubricant;
• and
• a dissymmetric hydraulic outlet chamber which is arranged to surround a part of the outer control ring circumference, the dissymmetric hydraulic outlet chamber being directly charged with the pump outlet pressure and being directly connected to the pump outlet for the pressurized lubricant,
• wherein,
• the effective anti-spring hydraulic surface in the dissymmetric hydraulic outlet chamber is larger than the pro-spring hydraulic surface which counter acts the effective anti-spring hydraulic surface.