Resources Contact Us Home
Method and system for controlling combustion engines

Image Number 4 for United States Patent #5769049.

A method and system for controlling combustion engines by detection of the present air/fuel ratio within the cylinders of the combustion engine, using an analysis of the characteristics of the ionization current, as detected via a measuring gap with a bias voltage applied being arranged in the combustion chamber, preferably using the spark plug gap in an Otto-engine. A measuring voltage corresponding to the degree of ionization is detected during the flame ionization phase and during a time- or crankshaft position dependent period A, B, C or D, which duration is dependent of the present air/fuel ratio, and will be finished by an amplitude maximum PF during the flame ionization phase. A parameter characteristic for the fundamental frequency of the measuring voltage during the period A, B, C or D is detected, which parameter indicates a tendency towards the rich direction of stoichiometric when the fundamental frequency increases, and inversely indicates lean tendency when the fundamental frequency decreases. The fundamental frequency is preferably detected from the differential value of the measuring voltage during the period A, B, C or D, in respect of time t or crankshaft degrees VC. dU.sub.ION /dt respectively dU.sub.ION /dVC. The differential value multiplied with a constant is used at least partly when determining a relative or absolute air/fuel ratio.

  Recently Added Patents
Stepped delay control of integrated switches
Systems and methods for DC-to-DC converter control
Selective facsimile denial
Image processing apparatus and image processing method
Peer to peer (P2P) missing fields and field valuation feedback
Display apparatus, control method thereof, and program
  Randomly Featured Patents
Liner with electrical pathways
Connecting device
Crystalline cepham acid addition salts and processes for their preparation
Band frequency indicating system
Electrical adapter assembly
Determining distribution for planning an infusion
Rocker switch with improved rocker actuator
Status notification system, status notification apparatus, and response apparatus
Locking bars for vacuum cleaner
Corona charger for image forming apparatus providing uniform surface charge of a recording medium