ELGi rotary screw compressors (specifically the EN and EG series), the coupling is the critical drive component that connects the electric motor to the air-end. ELGi typically utilizes Direct Drive technology in their premium models, meaning the motor and air-end are aligned on a 1:1 ratio via a flexible coupling to eliminate the energy losses associated with belt drives.The coupling ensures that the $\eta$-V profile rotors receive smooth, consistent torque while protecting the motor's bearings from the high-frequency vibrations generated during the compression process.