Simple
One screw rotor and two gate rotors which are positioned at right angle to the axis constitute two compressing rooms. Therefore, the screw rotor with six grooves compresses as many as 12 times per rotation.
Quietness

Without applying thrust load to the axis direction of the rotor, the force in the circumference direction rotates quietly with good balance. As a result, the load to the bearing is lightened, minimizing the generation of noise or vibration.
Durability

The gate rotors are rotated following the rotation of the screw rotor along its gear. The water film formed on the screw rotor's gear and the free floating mechanism maintains the high efficiency for a long time (in case of water lubrication).