HYDRAULIC PROTECTION DEVICE FOR SUBMERSIBLE OILFILLED ELECTRIC MOTOR Russian patent published in 2003 - IPC

FIELD: electromechanical engineering. SUBSTANCE: device that has housing, shaft mounted in journal bearings, at least two chambers arranged in tandem in axial direction and separated from one another by partitions, frame mounting flexible expansion device, end seals fitted in slit between frame and shaft, and safety valve is provided in addition with sump installed in bottom chamber and made in the form of cylinder with radial partitions which divide it into separate sealed sections, each partition being provided with holes. EFFECT: enhanced reliability of hydraulic protection device. 1 cl, 3 dwg