Coolant pump for a collant circuit of an internal combustion engine

Abstract

A coolant pump for a coolant circuit of an internal combustion engine, including a drive wheel which is connected to an impeller via a drive shaft rotatably mounted in a pump housing has at least one coolant outlet provided radially with respect to the impeller. A blocking ring is movable in an axial direction and serves to change or block a cross-sectional area of the coolant outlet and is displaced by a pressure-medium-operated actuator. The actuator is arranged concentrically with the drive shaft in the region of the end thereof facing the impeller is secured on the end of the drive shaft, and is connected to a pressure medium supply via at least one longitudinal bore provided in the drive shaft.

1 - 10 . (canceled) 
     
     
         11 . A coolant pump for a coolant circuit of an internal combustion engine, comprising:
 a drive wheel connected to an impeller via a drive shaft rotatably mounted in a pump housing;   at least one coolant outlet being provided radially with respect to the impeller;   a blocking ring movable in an axial direction and serving to change or block a cross-sectional area of the coolant outlet; and   a pressure-medium-operated actuator for displacing the blocking ring, the actuator disposed concentrically with the drive shaft in a region of an end of the drive shaft facing the impeller, the actuator being secured on the end of the drive shaft, the actuator being connected to a pressure medium supply via at least one longitudinal bore provided in the drive shaft.   
     
     
         12 . The coolant pump as recited in  claim 11  wherein the actuator takes the form of a hydraulic cylinder disposed coaxially at the end of the drive shaft. 
     
     
         13 . The coolant pump as recited in  claim 12  wherein a cylinder running surface of the hydraulic cylinder is formed directly in the drive shaft. 
     
     
         14 . The coolant pump as recited in  claim 11  wherein the actuator takes the form of a diaphragm. 
     
     
         15 . The coolant pump as recited in  claim 11  wherein the drive wheel is driven by a belt drive. 
     
     
         16 . A coolant pump for a coolant circuit of an internal combustion engine, comprising:
 a drive wheel connected to an impeller via a drive shaft rotatably mounted in a pump housing;   at least one coolant outlet provided radially with respect to the impeller;   a blocking ring movable in an axial direction and serving to change or block a cross-sectional area of the coolant outlet; and   a pressure-medium-operated actuator for displacing the blocking ring, the actuator being disposed concentrically with the drive shaft in a region of an end of the drive shaft facing the impeller, the actuator taking the form of a diaphragm.   
     
     
         17 . The coolant pump as recited in  claim 16  wherein the drive shaft receives at the end facing the impeller a flange-shaped first section of the impeller, the diaphragm being fixed by an edge to the first section of the impeller and the diaphragm being supported in a central region against a guide plate, the blocking ring being formed on the guide plate, the blocking ring annularly surrounding the coolant outlet when in a blocking position. 
     
     
         18 . The coolant pump as recited in  claim 17  further comprising a return spring counteracting movement of the guide plate in a blocking direction, the movement caused by the diaphragm. 
     
     
         19 . The coolant pump as recited in  claim 16  wherein the drive shaft receives at the end facing the impeller a flange-shaped first section, and a surface of the diaphragm facing the first section or another surface of the first section facing the diaphragm is structured. 
     
     
         20 . The coolant pump as recited in  claim 11  wherein a first section of the impeller is connected by vanes to a second section of the impeller axially spaced from the first section, the vanes extending through openings in the guide plate. 
     
     
         21 . The coolant pump as recited in  claim 11  further comprising a control pump and a control valve disposed in the pump housing, an operating port of the control valve being connected to the longitudinal bore. 
     
     
         22 . The coolant pump as recited in  claim 16  wherein the drive wheel is driven by a belt drive.