Patent ID: 6644942
Filing Date: 2003-11-11
Classification: F01C,F04C

Abstract:
A dual-rotor vacuum pump unit comprising a pump stator with at least one axial internal cavity receiving two parallel pump rotors mounted to rotate on corresponding bearings and coupled together at a first end by a set of gears enclosed in a gear casing containing oil, the first end of one of the pump rotors being extended axially by a drive shaft engaged in the rotor of a motor unit for driving the vacuum pump, the motor unit having a stator coil and being enclosed in a motor casing extending the gear casing, wherein:the motor casing and the gear casing form a common one-piece casing connected to the first end of the pump stator of the vacuum pump; inside the common one-piece casing, the stator coil of the motor unit is embedded in a leakproof resin providing sealing that prevents oil and gas escaping to the outside.