ULTRASONIC UNITIZED FUEL INJECTOR WITH CERAMIC VALVE BODY.

摘要

An ultrasonic fuel injector for injecting a pressurized liquid fuel into the combustion chamber of an internal combustion engine that uses an overhead cam for actuating the injector includes a valve body having an injector needle disposed therein forming a needle valve to meter the flow of fuel through the injector. The valve body is formed of ceramic material that is transparent to magnetic fields changing at ultrasonic frequencies. The injector needle includes a magnetostrictive portion disposed in the region of the valve body that is surrounded by a wire coil wound around the outside surface of the ceramic valve body. The wire coil is connected to a source of electric power that oscillates at ultrasonic frequencies. A sensor is configured to signal when the overhead cam is actuating the injector to inject fuel into the combustion chamber of the engine. The sensor is connected to a control that is connected to the power source and is configured to operate same only when the overhead cam is actuating the injector to inject fuel into the combustion chamber of the engine. When the power source activates the oscillating magnetic field in the coil and applies same to the magnetostrictive portion of the needle, ultrasonic energy is applied to the pressurized liquid. The method involves retrofitting a conventional injector with a needle having a magnetostrictive portion and with a ceramic valve body surrounded by wound wire coils configured and disposed to subject the magnetostrictive portion of the needle to ultrasonically oscillating magnetic fields.