Development of a Common-Rail Proportional Injector Controlled by a Tandem Arrayed Giant-Magnetostrictive-Actuator

This paper describes a performance of a newly designed pilot operated proportional injector for a 160MPa common-rail diesel fuel injection system. The main needle valve is supported by a hydro-mechanical position feedback servomechanism for proportional injection-rate control, and the pilot valve is operated by a tandem arrayed giant-magnetostrictive-actuator for quick motion control instead of a piezo-electric actuator for shortening the length and adapting to solid-state drive. The injector discharges injection-rates up to 30mm³/ms linearly to electric current within on/off lag times of 0.3ms(on ) and 0.5ms(off) from a nozzle of 6 holes × 0.16mm in diameter.