COMBINED CENTRIFUGAL GEAR PUMP Russian patent published in 2013 - IPC F04D13/12 F04C11/00 

FIELD: engines and pumps.

SUBSTANCE: pump includes gears, which are installed in housing wells and engaged. Roots of gear teeth include annular grooves with dividers of suction and discharge cavities, which are installed in them, and preswitched-on centrifugal impellers are fixed on the ends facing the inlet. On side walls of housing wells, on zones free from dividers, there made are spiral grooves with gradually increasing sections in the rotation direction of centrifugal impellers, which end with outlet channels interconnected with inlet of bypass valve. Valve outlet is connected to discharge cavity. Outlet sections of discharge channels are made in the form of straight-line diffusers. Bypass valve is equipped with opening pressure adjustment device.

EFFECT: invention allows balancing the joint operation of centrifugal and gear steps of combined centrifugal gear pump at operation at increased frequencies owing to bypassing some part of working fluid to discharge cavity, thus bypassing the gear step.

3 cl, 3 dwg