Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
169 words
A self-priming centrifugal pump comprising at least one fully loaded pump stage mounted on a shaft, a priming stage mounted rigidly on the same shaft in the manner of a side channel or liquid ring pump, the suction side of the priming stage being connected through a first, permanently open port with a first, suction side area of the fully loaded pump stage in which gas that is to be drawn off collects, the suction side of the priming stage being connected through a second, permanently open port with a second area of the fully loaded pump stage which, during normal operation, is at a higher pressure than the first area, whereby both the first and second ports are so designed that in normal operation a stream of liquid that is sufficient to cool the priming stage flows from the second area of the fully loaded pump stage to the suction side of the priming stage and from there to the first area of the fully loaded pump stage.
Claim 2
Dependent Claim
169 words
A self-priming centrifugal pump comprising at least one fully loaded pump stage mounted on a shaft, a priming stage mounted rigidly on the same shaft in the manner of a side channel or liquid ring pump, the suction side of the priming stage being connected through a first, permanently open port with a first, suction side area of the fully loaded pump stage in which gas that is to be drawn off collects, the suction side of the priming stage being connected through a second, permanently open port with a second area of the fully loaded pump stage which, during normal operation, is at a higher pressure than the first area, whereby both the first and second ports are so designed that in normal operation a stream of liquid that is sufficient to cool the priming stage flows from the second area of the fully loaded pump stage to the suction side of the priming stage and from there to the first area of the fully loaded pump stage.
Claim 3
Dependent Claim
46 words
A centrifugal pump according to claim 1, wherein the first port and the second port are connected to each other in the immediate proximity of a suction port of the priming stage so that the cooling stream passes in the immediate proximity of the suction port.
Claim 4
Dependent Claim
32 words
A centrifugal pump according to claim 1, wherein the walls of at least one of the first and the second port are arranged in close thermally conductive connection with the priming stage.
Claim 5
Dependent Claim
44 words
A centrifugal pump according to any one of claims 1 to 3, wherein the aforementioned second area of the fully loaded pump stage is an area forming part of the pressure side thereof axially to one side of a rotor of the pump stage.
Claim 6
Dependent Claim
48 words
A centrifugal pump according to any one of the claims 1 to 3, wherein the aforementioned first area of the fully loaded pump stage is an area that is connected with the suction side hub area of a rotor of the pump stage and axially adjacent the rotor.
Claim 7
Dependent Claim
50 words
A centrifugal pump according to claim 2 wherein a suction chamber is arranged in front of the suction port of the priming stage, the axial extent of this suction chamber being small, that is to say, not substantially larger than the half width of an impeller of the priming stage.
Claim 8
Dependent Claim
35 words
A centrifugal pump according to any one of the claims 1 to 3, wherein the second port includes a first canal which discharges into a geodetically deep located area of the fully loaded pump stage.
Claim 9
Dependent Claim
38 words
A centrifugal pump according to claim 7 wherein, apart from said canal, the second port includes a bore which discharges into the fully loaded pump stage next to a rotor thereof closer to the axis than said canal.