Patent ID: 6543700
Filing Date: 2003-04-08
Classification: F02M

Abstract:
An ultrasonic, unitized fuel injector apparatus for injection of pressurized liquid fuel into an internal combustion engine that actuates the injector by at least one overhead cam contacting a cam follower, the apparatus comprising:a valve body formed of ceramic material that is transparent to magnetic fields changing at ultrasonic frequencies, said valve body defining: a cavity configured to receive therein at least a first portion of an injector needle, a discharge plenum communicating with said cavity and configured for receiving pressurized liquid fuel and at least a second portion of said injector needle, a fuel pathway communicating with said discharge plenum and configured to supply the pressurized liquid fuel to said discharge plenum, and an exit orifice communicating with said discharge plenum and configured to receive the pressurized liquid fuel from said discharge plenum and pass the liquid fuel out of said valve body; a means for applying within said cavity a magnetic field changing at ultrasonic frequencies, said means being carried at least in part by said valve body; an injector needle having a first portion disposed in said cavity and a second portion disposed in said discharge plenum, said first portion of said injector needle being formed of magnetostrictive material responsive to magnetic fields changing at ultrasonic frequencies; a sensor configured to signal when the injector is injecting pressurized liquid fuel into the internal combustion engine; and a control connected to said sensor and to said means for applying within said cavity a magnetic field changing at ultrasonic frequencies, said control being configured to activate said means for applying within said cavity a magnetic field changing at ultrasonic frequencies when said sensor signals that the injector is injecting fuel into the combustion chamber of the engine.