US 6,981,489 B2 | ||
Method for controlling a fuel injector according to a control law which is differentiated as a function of injection time | ||
Michele Petrone, San Lazzaro Di Savena (Italy); Luca Mancini, Bologna (Italy); and Massimo Mattioli, Castelmaggiore (Italy) | ||
Assigned to Magneti Marelli Powertrain S.p.A., Corbetta (Italy) | ||
Filed on Jun. 05, 2003, as Appl. No. 10/455,559. | ||
Claims priority of application No. BO2002A0359 (IT), filed on Jun. 07, 2002. | ||
Prior Publication US 2004/0065747 A1, Apr. 08, 2004 | ||
Int. Cl. F04M 51/00 (2006.01) |
U.S. Cl. 123—490 | 29 Claims |
1. Method for controlling a fuel injector (1) for a controlled-ignition internal combustion engine provided with an electrically operated electromagnetic actuator (5) in such a manner as to open the injector (1) for a determined injection time (Tj); the method providing that the injector (1) be operated with a first current waveform (A) if the injection time (Tj) is greater than a predetermined threshold value (Ts), and that the injector (1) be operated with a second current waveform (B) if the injection time (Tj) is less than the predetermined threshold value (Ts); two current waveforms (A, B) sharing an identical initial part, during which the current (i(t)) passing through the injector (1) is caused to rise for a first time interval (T1) until it reaches a peak value (Ip), which is maintained for a second time interval (T2; T5) by cyclic switching of the voltage (v(t)) applied to the injector (1) between two different values (0, Vc); the method being characterized in that the second waveform (B) of the current (i(t)) provides for the current (i(t)) passing through the injector (1) to be maintained at the peak value (Ip) until the end of the injection time (Tj) and thus rapidly setting the current (i(t)) passing through the injector (1) itself to zero. |