A signal representing the RPM of an internal combustion engine is produced by a signal processor connected to the battery of the vehicle. The signal processor derives an electrical signal from the battery which contains signal components produced by operation of the vehicle ignition system, as well as components from a multitude of other sources such as the voltage regulator, fans, air conditioning and other electrical systems of the vehicle. The signal processor filters and signal processes the signal derived from the vehicle battery to produce a signal having a frequency which is related to the RPM of the engine.
申请公布号
US5004979(A)
申请公布日期
1991.04.02
申请号
US19900496103
申请日期
1990.03.16
申请人
BEAR AUTOMOTIVE SERVICE EQUIPMENT COMPANY
发明人
MARINO, JOSEPH A.;MAKHIJA, SURENDER K.;TAGHIKHANI, MAJID;PUETZ, PETER A.