CENTRIFUGAL ELECTRIC PUMPING UNIT Russian patent published in 2000 - IPC

FIELD: hydraulic machine engineering, possibly systems for heat control in aircraft and missile equipment. SUBSTANCE: centrifugal electric pump unit includes housing with inlet and outlet unions and with turning for placing casing with pump unit and electric motor. Diffuser of pump unit is in the form of groove on outer surface of casing. There is additional helical groove on outer surface of casing. One end of additional helical groove is dead, its other end is joined with groove of diffuser. In helical groove plunger is arranged with possibility of motion along said groove; cross section area of plunger is equal to that of groove. In casing at side of diffuser there is stopper limiting plunger motion. In cavity between plunger and dead end of helical groove return type compression spring is placed. Above mentioned cavity is connected with inlet union. Outer cylindrical surface of plunger embraces cross section of outlet union in zone of its joining with cylindrical surface of turning. EFFECT: enlarged manufacturing possibilities of unit due to prevention of back flow of working liquid through electric pump unit without increasing dimensions of said unit. 3 cl, 6 dwg