Patent ID: 7165953

Claim:
A device for conveying a liquid, said device comprising: a vertical pump comprising a pump housing with an inlet opening and a liquid discharge opening, a pump impeller rotatably mounted in said pump housing, an electric motor for driving the pump impeller, and a drive shaft connected between the motor and the pump impeller, wherein the drive shaft is enclosed by a shaft housing that is provided with a connector which is connected to a source of negative pressure, and above the pump impeller at least one gap in the shaft housing is provided for the drive shaft, and wherein, at least at the start of pumping, a negative pressure is generated in the shaft housing, said negative pressure extending through said gap into the pump housing to draw liquid through the inlet opening into the pump housing, wherein said source of negative pressure comprises an ejector through which purified cooling lubricant liquid is fed from a source independent of said vertical pump to generate the negative pressure.