Data processing: vehicles – navigation – and relative location – Vehicle control – guidance – operation – or indication – With indicator or control of power plant
Reexamination Certificate
2000-06-22
2002-06-18
Kwon, John (Department: 3754)
Data processing: vehicles, navigation, and relative location
Vehicle control, guidance, operation, or indication
With indicator or control of power plant
C701S102000, C324S399000
Reexamination Certificate
active
06408242
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to systems for diagnosing and controlling an ignition system of an internal combustion engine, and more specifically to such systems for detecting and logging predetermined ignition system failure modes as they occur and for controlling the ignition system in accordance with ignition system abnormalities.
BACKGROUND OF THE INVENTION
In electronic controls for internal combustion engines, it is known to electronically determine and control timing events associated with the engine ignition system in order to properly ignite air-fuel mixtures supplied to the engine. Typically, an engine control computer is responsive to crankshaft angle, engine coolant temperature, commanded engine fueling, intake air temperature and other engine operating conditions to produce appropriate firing command signals for generating high voltage sparks at a number of spark plugs, thereby resulting in combustion of the air-fuel mixture.
In the operation of a typical internal combustion engine ignition system, the engine control computer determines in a conventional manner an appropriate time to energize the primary side of an ignition coil associated with the engine (hereinafter referred to as a “firing command”). At that time, current begins to flow from a voltage source, such as a vehicle battery through the coil primary.
While the Muth et al. system is operable to distinguish between a normally operating ignition system and a misfire condition, it has several drawbacks associated therewith. For example, while it may effectively detect one or more misfire conditions, the Muth et al. system does not distinguish between any of the various possible ignition system failures. Thus, the Muth et al. system is incapable of providing any information relating to a particular cause of the misfire condition. Moreover, since the Muth et al. system is not operable to determine the cause of the misfire condition, it cannot properly use the misfire information to alter ignition and/or fuel strategies in real time to thereby minimize the effect of a particular cause of the misfire condition.
What is therefore needed is a system for diagnosing and controlling an ignition system of an internal combustion engine, wherein such a system is operable to detect, and distinguish between, a number of possible ignition system failure modes. Such a system should include at least the capability to store information relating to the types and number of occurrences of all ignition system failure modes which have occurred for later analysis, and should ideally be further capable of utilizing the information relating to any presently occurring ignition system failure mode to alter engine fueling, spark timing and/or spark energy during a subsequent firing command to thereby at least minimize the effect of the failure condition on proper engine operation.
SUMMARY OF THE INVENTION
The foregoing shortcomings of the prior art are addressed by the present invention. In accordance with one aspect of the present invention, a system for detecting ignition system failures comprises an ignition coil having a primary coil coupled to a secondary coil, means for energizing the primary coil to thereby induce a spark voltage in a high tension side of the secondary coil, a voltage sensor associated with the high tension side of the secondary coil, the voltage sensor sensing the spark voltage and producing a spark voltage signal corresponding thereto, and a computer having an input receiving the spark voltage signal. The computer analyzes the spark voltage signal and determines therefrom whether the spark voltage signal corresponds to an ignition system failure.
In accordance with another aspect of the present invention, a system for detecting ignition system failures, comprises an ignition coil having a-primary coil coupled to a secondary coil, means for energizing the primary coil to thereby induce a spark voltage in a high tension side and an ion voltage in a low tension side of the secondary coil, an ion sensor associated with the low tension side of the secondary coil, the ion sensor sensing the ion voltage and producing an ion voltage signal corresponding thereto, and a computer having an input receiving the ion voltage signal.
The computer analyzes the ion voltage signal and determines therefrom a combustion quality value associated with the spark voltage.
In accordance with a further aspect of the present invention, an apparatus for diagnosing ignition system failures comprises an ignition coil having a primary coil coupled to a secondary coil, means for energizing the primary coil to thereby induce a spark voltage signal in the secondary coil, and a first computer having an input coupled to the secondary coil for receiving the spark voltage signal. The computer includes a first memory having at least one spark voltage waveform stored therein corresponding to a spark voltage signal of a predefined ignition system failure mode, and the computer compares the spark voltage signal with the at least one spark voltage waveform and produces a diagnostic signal corresponding to a predefined ignition system failure mode if the spark voltage signal matches the at least one spark voltage waveform.
In accordance with yet another aspect of the present invention, an apparatus for predicting ignition system failures, comprises an ignition coil having a primary coil coupled to a secondary coil, a spark plug connected to a high tension side and to a low tension side of the secondary coil and defining a spark gap therebetween, an ignition control circuit connected to the primary coil and having an input responsive to a firing command to energize the primary coil to thereby induce a spark voltage in the high tension side of the secondary coil and a corresponding spark in the spark gap, the spark voltage exhibiting a voltage peak having a peak value corresponding to a breakdown voltage of the spark gap, and a first computer having an input coupled to the high tension side of the secondary coil for receiving the spark voltage. The first computer compares the peak value of the voltage peak with a threshold value and produces a prognostic signal corresponding to a predefined ignition system failure mode if the peak value is greater than the threshold value.
In accordance with still another aspect of the present invention, an apparatus for predicting ignition system failures, comprises an ignition coil having a primary coil coupled to a secondary coil, a spark plug connected to a high tension side and to a low tension side of the secondary coil and defining a spark gap therebetween, an ignition control circuit connected to the primary coil and having an input responsive to a firing command to energize the primary coil to thereby induce a spark voltage in the high tension side of the secondary coil and a corresponding spark in the spark gap, the spark voltage exhibiting a voltage peak having a peak value corresponding to a breakdown voltage of the spark gap, and a first computer having an input coupled to the high tension side of the secondary coil for receiving the spark voltage. The first computer compares a slope of the voltage peak about the peak value with a predefined slope value and produces a prognostic signal corresponding to a predefined ignition system failure mode if the slope of the peak value is less than the predefined slope value.
In accordance with yet a further aspect of the present invention, an apparatus for diagnosing ignition system failures comprises an ignition coil having a primary coil coupled to a secondary coil, a spark plug connected to a high tension side and to a low tension side of the secondary coil and defining a spark gap therebetween, an ignition control circuit connected to the primary coil having an input responsive to a firing command to energize the primary coil to thereby induce a spark voltage in the high tension side of the secondary coil and a corresponding spark in the spark gap, the spark voltage exhibiting a voltage peak having a peak value corresponding to a breakdown
Barnes & Thornburg
Cummins Inc.
Kwon John
Vo Hieu T.
LandOfFree
Apparatus and method for diagnosing and controlling an... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for diagnosing and controlling an..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for diagnosing and controlling an... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2908862