Abstract: A misfire-detecting system detects a misfire occurring in an internal combustion engine. A value of sparking voltage for discharging a spark plug of the engine is detected. A differentiating circuit differentiates the detected value of the sparking voltage. A misfire-determining circuit compares the differential value of the sparking voltage with a predetermined value, and determines, based upon a result of the comparison, whether a misfire has occurred in the engine.

Abstract: A device for diagnosing the state of health of an ignition system is provided, where the system includes at least one spark producing channel comprising an exciter, output circuit and igniter plug. The device provides a diagnosis of the state of health for both the exciter and igniter plug by monitoring the high energy pulses at the output of the exciter. By monitoring the ignition system at an intermediate point in the system such as the output of the exciter, the sensor and electronics of the device may be completely contained within the electronic environment of the exciter, thereby avoiding any need for attaching sensors at the output of the system adjacent to the igniter plug in order to diagnose the plug's state of health. As an alternative to the device being built into the ignition system, it can be incorporated into automatic test equipment that produces high energy pulses for delivery to an igniter plug to be tested.

Abstract: An interface for coupling an engine analyzer to an engine having a distributorless ignition system includes a pair of pickup clamps for coupling signals from respective groups of spark plug wires. A logic cell array is supplied with spark plug secondary voltage polarity and pattern information, corresponding to an engine under test from a ROM. The technician is instructed as to which wires to place in each clamp. A semiconductor input switch is controlled by the logic cell array to sort the secondary voltages from the pickup clamps according to polarity. The real and the wasted sparks are then determined based upon the magnitude of the signals from the input switch. The apparatus permits a "rapid test" (of secondary voltages only) by developing a pseudo primary clock from the pickup clamp signals. A CPU in the interface is controllable by an external computer or by an operator keypad.

Abstract: An interface for coupling an engine analyzer to an engine having a distributorless ignition system includes a pair of pickup clamps for coupling signals from respective groups of spark plug wires. A logic cell array is supplied with spark plug secondary voltage polarity and pattern information, corresponding to an engine under test from a ROM. The technician is instructed as to which wires to place in each clamp. A semiconductor input switch is controlled by the logic cell array to sort the secondary voltages from the pickup clamps according to polarity. The real and the wasted sparks are then determined based upon the magnitude of the signals from the input switch. The apparatus permits a "rapid test" (of secondary voltages only) by developing a pseudo #1 primary clock from the pickup clamp signals. A CPU in the interface is controllable by an external computer or by an operator keypad.

Abstract: A device for diagnosing the state of health of an ignition system is provided, where the system includes at least one spark producing channel comprising an exciter, output circuit and igniter plug. The device provides a diagnosis of the state of health for both the exciter and igniter plug by monitoring the high energy pulses at the output of the exciter. By monitoring the ignition system at an intermediate point in the system such as the output of the exciter, the sensor and electronics of the device may be completely contained within the electronic environment of the exciter, thereby avoiding any need for attaching sensors at the output of the system adjacent to the igniter plug in order to diagnose the plug's state of health. As an alternative to the device being built into the ignition system, it can be incorporated into automatic test equipment that produces high energy pulses for delivery to an igniter plug to be tested.

Abstract: An ignition adapter for DIS four stroke engines provides conventional voltage waveforms for a diagnostic oscilloscope. Spark plug leads from a DIS four stroke engine are grouped together depending on their respective firing polarity. A first signal pickup is placed around the spark plug leads from the spark plugs of one signal polarity, for example a positive signal polarity, and a second signal pickup is placed around the spark plug leads from the spark plugs of opposite polarity, for example a negative signal polarity. A trigger pickup is placed around the #1 cylinder spark plug lead. The voltage waveforms received in the signal pickups are applied to the ignition adapter, summed and displayed on the oscilloscope as a conventional voltage waveform. The polarity of the waveform can be reversed using a polarity switch. The waveform received in the trigger pickup is applied to the ignition adapter and compared to a reference voltage.

Abstract: A direct fire ignition system for an internal combustion engine having a coil assembly attachable to each spark plug. Each coil assembly has a high voltage transformer for producing a voltage sufficient to cause the spark plug to generate a spark, an integral capacitor parallel with the spark plug, and a spark plug sensor circuit coupling to the high voltage transformer for generating a spark confirmation signal when a spark is generated. The spark sensor circuit is responsive to a high frequency signal generated in the high voltage transformer within a predetermined frequency range to generate the spark confirmation signal. The direct fire ignition system is compatible with single strike or multi-strike modes of operation. The system can also generate a probe voltage across the spark plug to test for auto or pre-ignition.

Abstract: A distributorless ignition system using a dual-spark ignition coil generates a signal indicative of which of the two cylinders associated with the dual-spark coil is operating in its power stroke by means of a single detector connected to a predetermined one of the cylinders. The output of the detector is fed to a sample and hold circuit which supplies the peak value from the detector to the control unit of the ignition system where the peak value is evaluated and identified by comparison to a previously obtained peak value. The control unit indicates that the predetermined cylinder is in its power stroke when the detected peak value signal is at its higher level. Conversely, when the peak value signal is at its lower level the control unit determines that it is the other of the two cylinders which is in its lower stroke and signals this accordingly.

Abstract: An inductive pickup assembly senses the electromagnetic fields of plural ignition elements of an automotive engine, access to which elements is prevented by associated engine housing structure. The pickup assembly includes a frame having a flat platform on which multiple sensors are mounted, each sensor comprising an electromagnetic pickup coil with a magnetizable metal core integral with a magnetizable metal shield plate which covers one end of the coil. The frame has a support member with depending feet having apertures which mate with fasteners on the housing structure to serve as a template for accurately locating the pickup assembly on the housing structure.

Abstract: Ignition timing of an internal combustion engine of an automotive vehicle is automatically adjusted by idling the engine with a distributor whose coil terminal and spark plug terminals are disconnected from ignition circuit and detecting an spurious ignition signal for a specified cylinder from the distributor. The distributor is turned with respect to the engine through an angle in accordance with a difference between a rotated angle of the crankshaft of the engine from a detection of the spurious ignition signal to a provision of a top dead center signal and a predetermined angle of the crankshaft for an expected ignition timing.

Abstract: An ignition monitoring circuit for an ignition system of an internal combustion engine of an automobile, which comprises, in addition to a pulse height and a pulse width shaper circuit, a circuit for eliminating an initial erroneous pulse which is generated from the pulse width shaper circuit upon making of the key switch. The pulse height shaper circuit shapes impulses corresponding to an ignition voltage into pulses of predetermined height; the pulse width shaper circuit shapes the output pulses of the pulse height shaper circuit into pulses of predetermined width. The eliminating circuit comprises: a serial circuit of a resistor, a diode, and a capacitor, coupled across the battery; and a transistor, having its base coupled to the output terminal of the pulse height shaper circuit through an inverter, which is coupled in parallel with the serial connection of the diode and the capacitor.

Abstract: An ignition system for internal combustion engines comprises means for generating an ignition signal in synchronism with the revolution of an internal combustion engine and an ignition circuit device for interrupting a primary current of an ignition coil in accordance with the ignition signal. The ignition circuit device includes an ignition monitor signal producing circuit for producing an ignition monitor signal which circuit operates to set the ignition monitor signal at the time of starting the energization of the ignition coil and thereafter to reset the ignition monitor signal at a subsequent predetermined timing, whereby the ignition circuit device operates, in accordance with the pulse width and the set and reset conditions of the ignition monitor signal, to decide whether the operation of the ignition circuit device is normal or abnormal, to control to generate a predetermined amount of ignition energy, and to prevent erroneous generation the ignition monitor signal due to a noise or the like.

Abstract: A technique for detecting misfire due to a fault in the secondary of an automotive ignition system compares the ignition signal developed by the ignition coil, preferably the primary winding thereof, to reference signals. Abnormal results which occur at predetermined times subsequent to the initiation of the ignition signal indicate short circuit and/or open circuit conditions in the ignition system's secondary. In response to such fault conditions, fuel is preferably shut off to the cylinder associated with the misfire.

Abstract: A test circuit for setting the synchronizatiom of a dual ignition system, particularly of an aircraft engine dual magneto system, having an oscillator circuit 3, two transformers 23, 24 connected to the oscillator circuit, said transformers receiving the oscillator signal at a cener-tap of their primary windings, in which the primary windings are connected at one end to a common potential and having at least two connections for connecting the test circuit to the ignition system to be tested, said two connections each being connected to the other end of the primary winding 23, 24. Secondary windings 27, 28 of the transformers 23, 24 are connected to indicator elements 29, 30.

Abstract: The invention relates to a method and an arrangement for detecting ionizing current in an ignition circuit incorporated in the ignition system of an internal combustion engine, in which a measuring voltage is applied to the ignition circuit in at least one secondary winding, and in which a measuring device is used to detect the possible presence of an ionizing current in the ignition circuit. A low measuring voltage is applied during an engine start sequence, or alternatively, no measuring voltage at all, and a high measuring voltage is applied subsequent to the engine start. The invention thereby overcomes the problem existing when measuring ionizing currents of the spark plugs becoming coated with soot deposits as a result of the electrical voltage field which always exists between the electrodes of respective plugs. Such problem is particularly troublesome during an engine start sequence, since the deposits can prevent the engine from starting.

Abstract: Disclosed are self-extinguishing polystyrenic compositions with improved thermal stability properties, comprising a styrenic resin and a fire-retardant agent which can either comprise solely a brominated pentaerythritol having at least one free-OH group or such a compound in combination with a peroxide.

Abstract: An on-vehicle diagnostic unit for an electronic ignition system monitors input signal received and output signals produced by the electronic ignition control unit on a continuous basis and displays an indiction of proper operation or failure. The failure indication is produced in response to a permanent or intermittent failure, irrespective of the failure mode of the electronic ignition control unit.

Abstract: A method and apparatus for testing ignition systems of internal combustion engines in motor vehicles, in which an ignition voltage signal on the primary side for one ignition operation or averaged for several ignition operations is compared with a should-be signal and the electrode distance of a spark plug is determined in that the should-be signal is taken at the beginning of a service interval and under an operating condition which at least approximately equals the actual operating condition at the point of time of the test.

Abstract: An ignition diagnostic monitor detects ignition malfunction. A first monostable multivibrator is coupled to an ignition module to receive the ignition signal and maintain a first logic state for a predetermined first time constant after detecting an ignition signal. The monostable multivibrator maintains a second logic level state after passage of the predetermined time constant until detection of another ignition signal occurs. The second logic level indicates a missed ignition signal and an ignition fault. A control module is coupled to the ignition module and the monostable multivibrator and receives a fault detection signal from the monostable multivibrator.

Abstract: The diagnostic device comprises voltage divider resistors, two comparators, a start switch, a microcomputer, two transistors, and two light emitting diodes. The ignition signal is voltage-divided by the voltage divider resistors, and the result of this voltage division is input into the positive terminals of the comparators. Reference voltages are input to the negative terminals of the comparators which determine how high the inputs to the positive terminals must be for each comparator to have an "H" level output. When the start switch is turned ON the device starts to operate. In the microcomputer, which has a timer function built in, the interrupt terminal (INT) becomes connected to the output terminal of the comparator; the reset terminal (RES) becomes connected to the start switch.

Abstract: This specification discloses testing vehicle primary ignition systems by taking the integral of the primary spark plug firing voltage versus time over a time period when the spark should occur. To determine when an integration output should be evaluated, a phase locked loop circuit is used to predict the occurrence of an ignition firing pulse. To compensate for changes in engine speed and yet disregard extraneous spark plug firings, the phase locked loop circuit contains two loop filters having different response times which are automatically selected to minimize response to erroneous or missing spark plug firings and maximize response to actual engine RPM changes.

Abstract: A system for electronically detecting the transient state of engine operation of an internal combustion engine having a spark ignition system. A measuring circuit counts pulses having the pulse separation of the ignition timing of the spark ignition system and produces data output. A plurality of memorizing circuits are provided for memorizing old data output from the measuring circuit and a subtractor compares the old data output and the memorizing circuit with the new data output from the measuring circuit and produces the difference between the data and the amount of the difference. The output of the subtractor is used for correcting the air-fuel ratio of the air-fuel mixture of an emission control system using a three-way catalytic converter.

Abstract: An apparatus for testing an i.c.e. ignition system of the kind including an ignition coil and a semi-conductor switch means controlling current interruption in the coil primary, includes a voltage comparator connected to compare the voltage across the switch means with a predetermined voltage. The comparator output starts a monostable timer circuit, the output of which is gated with the output of the comparator to produce an output signal only if the voltage across the switch means falls below the predetermined voltage within a predetermined time duration.

Abstract: A test apparatus for testing electronic ignition systems includes a circuit for detecting the interruption of ignition coil primary current and triggering a 100 .mu.S monostable. A coil current detector detects when coil current flow is recommenced and the signals from this detector and the monostable are combined via a gate to indicate satisfactory operation if the detector detects current re-commencement within 100 .mu.S of the previous current interruption.

Abstract: A test apparatus for testing internal combustion engine spark ignition systems includes input terminals for connection across the electronic switch of the ignition system under test. A plurality of comparators are connected to compare the voltage across the input terminals with different reference levels and the comparator outputs are connected via peak storage circuits to a logic circuit which drives indicators indicating various fault conditions.

Abstract: A simplified, electronic circuitry, testing apparatus for performing voltage, continuity, open circuit or dynamic signal substitution testing of each individual major component within an automotive-type transistor ignition system preferably having a multi-function control for connecting a single pair of test probes to any of various test circuitry subcircuits thereof, a signal generator may be included therein, a plurality of discrete display components integral to the test subcircuits may display test results, this testing apparatus being capable of being powered by the electrical power source for the engine ignition system and preferably containing safety devices for preventing electrical damage to the ignition system under test or to the testing apparatus itself; preferably a separate adapter component and a separate spark indicator component which establishes a precise test spark gap may be connected as part of the testing apparatus.