Italian transmission manufacturer Oerlikon Graziano has introduced a new 4-Speed Electric Drive (4SED) transmission for electric and hybrid vehicle customers around Europe.
Based on the manufacturer's original eDCT, the 4SED uses two traction motors in a small powertrain which offers four speeds that is claimed to allow peak efficiency of about 90%, an overall efficiency improvement of about 15%.
Oerlikon Graziano Drive Systems Segment CEO Heriberto Diarte said, "This is a fully new transmission concept which will advance the development of electric vehicles."
The new transmissions are expected to address the need for efficient transmissions for low and zero emission vehicles.
The transmission's configuration uses two input shafts, which are driven by their own electric motor, while the two motors replace the twin clutches and the synchronizers and allow pre-selection of the next gear before the current is changed and also synchronizes shaft speeds.
According to the company, the use of traction motors facilitates a reduced set of software algorithms compared to a normal automated gearbox, and the equipment does not have hydraulics, which reduces the need for valve control.
The technology can be used in vehicle types including urban electric cars, high performance cars, hybrid 4WD applications, electric buses and trucks.