Patent ID: 8353687

Claim:
A rotary pump, which can be driven by an electronically commutated DC motor with an axial gap, a wound stator, and a motor shaft, the rotary pump comprising: a dry chamber, in which the wound stator is accommodated; a permanent magnetic pump impeller; a fluid-fillable pump space, in which the pump impeller is accommodated to rotate; a split plate for separating the pump impeller from the wound stator; a return ring connected to and in heat conducting contact with the split plate, the return ring being made up of a stack of sheet rings; a plurality of poles connected to the split plate; a heat-conducting element made from a heat conducting metal, wherein the heat-conducting element includes a disk aligned at right angles to the motor shaft or an annular disk with a tube connected to it in one piece open or closed to the motor shaft and extending coaxially in the direction toward the pump impeller; means for securing the return ring to the heat-conducting element; and a circuit board connected to the heat-conducting element on the side facing away from pump impeller.