Patent ID: 6140725
Filing Date: 2000-10-31
Classification: F04D

Abstract:
A wet-running submersible motor for driving a centrifugal pump, with a shaft in the rotor space, fillable with fluid, of the motor and carrying an electrical rotor, the shaft being formed hollow at least on its longitudinal section on the pump side, and with a sealing formation provided in a terminal wall on the pump side of the motor and surrounding the shaft for sealing the rotor space with respect to the pump, said shaft is mounted in sliding bearings arranged in front of and behind the rotor and is provided with radial flow passages within the motor, wherein the hollow shaft end on the pump side comprises a valve passable in the direction to the pump, with a spring loaded valve body in order, on operation of the motor, to let through fluid out of the rotor space to the pump for the purpose of bleeding said rotor space which can be filled automatically with a delivery fluid from the pump at least via said sealing formation in said terminal wall and to reduce excess pressure in said rotor space with respect to a fluid pressure in the pump acting on said motor.