| 摘要 |
A compressor in accordance with the present invention includes a male rotor which is axially aligned with and in communication with two female rotors. The male rotor is driven by a motor, in other words the male rotor is the drive rotor. The male rotor has a plurality of lobes which intermesh with a plurality of flutes on each of the female rotors. The male rotor comprises an inner cylindrical metal shaft with an outer composite material ring mounted thereon. The ring includes the lobes of the male rotor integrally depending therefrom. The lobes of the male rotor being comprised of a composite material allows positioning of the female rotors at a small clearance from the male drive rotor. This clearance is small enough that the liquid refrigerant itself provides sufficient sealing, cooling and lubrication. The positioning of the female rotors on opposing sides of the male rotor balances the radial loading on the male rotor thereby minimizing radial bearing loads. The interface velocity between the male and female rotors during operation is low, whereby damage suffered as a result of lubrication loss is reduced. The compressor includes a housing having an inlet housing portion, a main housing portion and a discharge housing portion. An induction side plate and a discharge side plate are mounted on the male rotor. The outside diameter of the induction plate is equal to the root diameter of the male rotor. The outside diameter of the discharge plate is equal to the crest diameter of the male rotor. These plates serve two purposes, to secure the male rotor components and to equalize suction pressure at both ends of the male rotor, thereby virtually eliminating the thrust loads. Discharge porting is defined in the discharge housing portion wherein trap pocket relief is provided. |
