Controllable coolant pump

Controllable coolant pump having a one-part or multi-part pump housing (1), a flow entry region (2) and a flow exit opening (3) for exit of the controllable conveyed volume stream, a pump shaft (5) mounted in/on the pump housing (1) in a pump bearing (4), driven by a belt pulley, for example, an impeller wheel (6) disposed at the free, flow-side end of this pump shaft (5), so as to rotate with it, a pump chamber rear wall (7) disposed in the pump housing (1), between the impeller wheel (6) and the pump bearing (4), a wall plate (8) fixed in place on the housing, disposed between the impeller wheel (6) and the pump chamber rear wall (7), having one or more working cylinder(s) (9) disposed in the pump housing (1), in which one or more working piston(s) (10) is/are disposed to be movable, activated by control pressure, on which piston(s) the rear wall (12) of a valve slide (13) having an outer cylinder (14) is disposed, which cylinder variably covers the outflow region (15) of the impeller wheel (6), as a function of the control pressure, wherein a reset spring (11) is disposed between the wall plate (8) fixed on the housing and the working piston(s) (10) that can be moved in the longitudinal pump shaft direction or the valve slide (13) that is connected with the working piston(s) (10), wherein

• a seal (18) is disposed on the outer edge (17) of the wall plate (8), between the edge and the outer cylinder (14) of the valve slide (13), and
• wherein one or more additional flow outlet opening(s) (16) is/are disposed on the pump housing (1), the outlet volume stream of which openings can be additionally controlled, aside from the controllable volume stream that exits from the flow outlet opening (3), and
• wherein the flow outlet opening (16) from which the controllable volume stream exits is connected with an outflow opening (22) disposed in the region of the rear wall (12) of the valve slide (13), in the pump chamber rear wall (7), by way of an outflow channel (21), wherein the outflow opening (22) is enclosed by a ring seal (23) disposed in the pump chamber rear wall (7), which enters into operative engagement with the valve slide (13) in its rear end position.