Patent · US Expired

Fuel injector failure detection circuit

US5469825A · kind A · utility

32Cited by
26References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1994
Grant dateNov 28, 1995
Priority date
Expiry dateSep 19, 2014

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2041/2093
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

In a engine and associated fuel injector failure detection circuit, the engine having at least one combustion chamber, a battery, and at least one fuel injector having a high side and a low side terminal for introducing a fuel in the at least one combustion chamber, the fuel injector failure detection circuit comprising a one shot timer for transmitting a constant voltage state signal output when the fuel injector reaches a set current threshold at a start of an injector current peak time duration. A voltage sense comparator is provided for transmitting a low voltage state signal output when the low side terminal of the fuel injector produces a fly-back voltage pulse. A mechanism for monitoring current of the fuel injector during a rise time duration and the peak time duration ia also included. The circuit further provides a mechanism for disconnecting all electrical power supplied to the at least one fuel injector if the injector current fails to reach a peak level during the rise time duration or the fly-back voltage pulse fails to occur at the end of the peak time duration. Moreover, a mechanism for monitoring the fly-back voltage pulse produced by the low side terminal of the f…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.