VERTICAL TIGHT ELECTRICALLY DRIVEN PUMP Russian patent published in 2011 - IPC F04D13/06 F04D7/06 

FIELD: engines and pumps.

SUBSTANCE: proposed pump comprises encased wheel rotor 1, device to discharge gas from rotor upper chamber 12 into suction chamber 15 via through channel 13 in rotor shaft 1, tubular cooler 17 and impeller 2 fitted on shaft 3. Rotor chamber 12 is additionally communicated with chamber 18 accommodating cooler 17. Chamber 18 communicates with impeller suction chamber 9 communicated, in its turn, with wheel rotor pressure chamber 11. Impeller 2 may be arranged above wheel rotor 1 and aligned with lower thrust bearing.

EFFECT: efficient operation and higher reliability.