The belt-driven coolant pump works on the principle of a centrifugal pump. By means of a rotating impeller, centrifugal force is used to transport liquids. An additional two-stage coupling is integrated on the bearing of the water pump. This is electrically controlled. The clutch allows (in connected stage) a direct line from the belt pulley speed at the impeller.
When the clutch is disengaged, the speed of the impeller is reduced due to the principle of an eddy current brake. The coolant delivery is directly related to the impeller speed, thus ensuring that the coolant circuit is sufficiently supplied with coolant. The drive power of the water pump is also reduced.
Reduction of fuel consumption and emissions, through an adequate supply of coolant