Compressor

Abstract

A helical screw rotor compressor adapted for working against a pressure container whose pressure P is allowed to vary between a lowest pressure P 2 and a highest pressure P 1 , said compressor being driven by an electric motor. The electric motor is characterised by having in one operating range defined by the pressure interval P of said pressure container a quality such that halving of the torque of said motor will result an increase in motor speed of at least of 6 percent. It is also preferred that the compressor is optimised for an internal volume factor at which the pressure of the compressor will be lower than P 2 +0.85*(P 1 −P 2 ) at the opening instance.

1 . A helical screw rotor compressor (K) which is adapted to work against a pressure container (T) whose pressure (P) is allowed to vary between a lowest pressure P 2  and a highest pressure P 1 , said compressor (K) being driven by an electric motor (M), wherein in an operating range defined by the pressure interval P of the pressure container (T) the motor has a characteristic such that halving of the torque of said motor will result in an increase of at least six percent in the speed of said motor.  
   
   
       2 . A compressor (K) according to  claim 1 , characterized in that the electric motor (M) has a characteristic such that halving of the torque of said motor will result in an increase in the speed of said motor by at most 100 percent.  
   
   
       3 . A compressor (K) according to  claim 1 , characterized in that the electric motor (M) is a commutator motor.  
   
   
       4 . A compressor (K) according to  claim 1 , characterized in that the compressor (K) is optimised for an internal volume factor at which the pressure of the compressor (K) is lower than P 2 +0.85*(P 1 −P 2 ) at the opening instance.  
   
   
       5 . A compressor (K) according to  claim 4 , characterized in that the compressor (K) is optimised for an internal volume factor at which the pressure of the compressor (K) is equal to the lowest working pressure P 2  in the pressure container at the opening instance.  
   
   
       6 . A compressor (K) according to  claim 4 , characterized in that the compressor (K) is optimised for an internal volume factor at which the pressure of the compressor (K) is lower than the lowest working pressure P 2  in the pressure container at the opening instance.