CENTRIFUGAL SCREW PUMP Russian patent published in 2012 - IPC F04D9/04 F04D29/66 F04D13/02 

FIELD: engines and pumps.

SUBSTANCE: centrifugal screw pump includes housing, impeller 2 with hub 3, which is installed on shaft 1, and screw 5 installed on additional shaft 6 by means of conical nut 7. Screw 5 has the possibility of axial movement and is spring-loaded to the end face on the pump outlet side with spring 20 installed on additional shaft 6. Cavity 11 in which nozzle assembly 10 and runner 9 of hydraulic turbine are arranged is made in hub 3 of impeller 2. Bushing 8 is connected to additional shaft 6 through face magnetic clutch 16 comprising drive and driven half-clutches 17, 18 with constant magnets 19. In impeller 2 there are holes 14 which connect the cavity of impeller 2 to cavity 12 before nozzle assembly 10 of hydraulic turbine. Radial holes 25 are made in drive half-clutch 17 and conical nut 7, and axial hole 23 is made in additional shaft 6 for formation of return channel of some part of pumped product passing through hydraulic turbine to the pump inlet.

EFFECT: improving cavitation properties of pump.

3 cl, 3 dwg