Abstract: In a pulse width control circuit receiving a periodic input signal and controlling the width of an output pulse by means of a negative feedback loop, the value of power source voltage is detected and when a prescribed power source voltage is detected, the amount of the negative feedback is varied in response to the detection of the prescribed power source voltage to vary the width of the output pulse correspondingly.

Abstract: A device for controlling the ignition and the fuel injection of an internal combustion engine, including a pressure sensor, a position sensor associated with a target fixedly mounted in rotation with the crankshaft, a first computer of the programmed microcomputer type in which are stored values of the angle of advance and the injection time addressable as a function of the engine speed and pressure parameters, and a second computer which, from the output signal of the position sensor applies to the first computer a synchronization signal assuring the marking of each top dead center and/or each bottom dead center, the first computer receiving the output signal from the pressure sensor and computing, as a function of the parameters and under the control of the synchronization signal, the injection time and the angle of ignition advance, the value of the latter being applied by the first computer from the second computer which computes the conduction angle of the ignition coil and controls the conduction of the

Abstract: A speed-dependent ignition controller and method utilizes a sensor output signal to provide spark occurrence and dwell initiation at retard and advance angles for an internal combustion engine. The sensor signal has a pulse width proportional to the difference between a desired ignition advance and retard angle. At low rpm, the sensor signal is inverted to produce a retarded ignition angle while at high rpm's the signal is utilized without inversion to produce an advance ignition angle.

Abstract: An electronically controlled ignition system is provided in which the point in time at which the primary current flowing through the primary winding of the ignition coil starts, is controlled as a function of speed so that the said primary current only reaches the value required for ignition just before the ignition time and in which immediately before the ignition time, it is ascertained whether the primary current has reached the value required for ignition, wherein if there is no primary current or insufficient primary current to prevent ignition during periodic fluctuations in speed, the electronic control arrangement is switched off for a fixed period and the time at which the primary current is used is derived directly from the control signal of the ignition pulse generator and in which, once the switch off period has come to an end, continuous and automatic electronic control is reinstituted.

Abstract: An ignition coil control circuit compares the coil input current with a reference level, and the duty ratio of the output current is altered accordingly. The reference level is raised during cold weather operations, raising the duty ratio. Once the operating temperature of the engine rises above a predetermined level, a detector circuit activates a control signal generator which lowers the reference level received by the comparator to lower the duty ratio accordingly.

Abstract: An output stage of a calculator (2) has a transfer function of the form: tc=N.TSD+.epsilon. where .epsilon. is a small and known quantity; t.sub.c is the conduction time of the coil, N is a number of angular fractions or periods of an interpolation signal; and TSD is the period corresponding to one tooth on the starter gear. The device comprises measurement means (1, 32, 36) for measuring the time strictly necessary to obtain the required energy; means (6, 9, 13, 17) for generating signals at each fraction of the angular marking signal in order to obtain a time measurement of a counting window and means (21, 25, 29) for counting and memorizing during this window an interpolation signal of the angular resolution n times higher.

Abstract: A countdown counter (14) counts out a speed dependent number to determine the start of the dwell period when a comparison number (Z17) is reached which is adjusted dynamically by a regulation counter (17). The countdown counter's contents are reduced by a value dependent upon acceleration when acceleration is present in order to improve the dynamic correction. In the case of strong accelerations these dynamic corrections are insufficient and when such a strong acceleration occurs the regulation counter content is set to a high value to assure a succession of strong ignition sparks. The high value of acceleration necessary for this precaution may be determined by comparing the difference of successive engine speed counts with a predetermined value or it may be determined by the failure of the current in the ignition coil primary to reach some predetermined value.

Abstract: An ignition system has an electronic control unit which produces trigger pulses in response to received ignition control signals, the control unit also receiving test pulses indicating the period of time for which current supplied to the primary winding of the ignition coil is at its maximum value, the control unit extending the test pulses and supplying the extended pulses to a logic circuit which, when a trigger pulse occurs without an extended pulse simultaneously occurring, produces an output signal to indicate misfiring, and to temporarily switch off the control.

Abstract: An electronic ignition system which is responsive to timing signals generated in timed relationship for providing a substantially constant percent excess dwell time. The timing signals are developed across a sensor coil that is floated between first and second inputs of the system. A capacitor is coupled through a buffer circuit to one of the inputs of the system wherein the timing signal is superimposed onto the voltage developed across the capacitor. A charge and discharge circuit comprising a pair of resistive current sources is utilized to charge and discharge the capacitor during operation. The ratio of the resistive components produces a constant percent excess dwell time that is substantially independent to temperature and process variations.

Abstract: An ignition system for a multi-cylinder internal combustion engine having a spark plug within each engine cylinder, wherein a single DC-DC converter is provided and a high-voltage withstanding characteristic capacitor is provided for each spark plug. The capacitor charges to the high DC output voltage of the DC-DC converter and operatively supplies the high DC voltage via a boosting transformer into the corresponding spark plug at a predetermined ignition timing. The amount of the discharge energy being varied according to the pulse width of an input signal of each switching circuit which operates to supply the charged high DC voltage of the capacitor into the corresponding spark plug, the pulse width being varied according to various engine operating conditions.

Abstract: Energizing interval of an ignition coil, which is basically determined on the basis of the rotational speed of an engine, is corrected by adding thereto an extension amount which is either a function of the rotational speed of the engine or a given upper limit value at the rotational speed of the engine when accelerating condition is detected. Thus, the ignition coil is supplied with a primary winding current for a desired interval even during acceleration so that sufficient ignition voltage will be produced to properly ignite air/fuel mixture in engine cylinders. The extended energizing interval is then reduced stepwise to provide normal energizing interval during engine operations other than acceleration.

Abstract: A circuit arrangement for controlling the duration of a current generated in the primary winding of an ignition transformer comprises a ramp generator responsive to the ignition timing or an internal combustion engine for generating a ramp voltage having a constant peak value and a variable rate of increase in voltage as a function of the speed of the engine. A pulse generating means is provided for successively generating a pulse of which the pulse height is substantially equal to the peak value of the ramp voltage and of which the pulse duration is variable inversely as a function of the speed of the engine. To the pulse generating means is coupled an integrator for integrating the pulses supplied thereto to generate an integrated output. The output of the integrator is supplied to a comparator for making a comparison with the instantaneous value of the ramp voltage to generate an ignition current pulse having a duration corresponding to the difference between the compared input variables.

Abstract: The period of conduction of an electronic interrupter of an ignition circuit is made shorter increasingly with falling engine speed in comparison to the duration of the period for which the switching path of the engine driven timing generator maintains its condition immediately before the ignition moment. During the time in which that condition is maintained immediately before changing at the ignition moment a capacitor (26) is provided with a first change (b) of its charge in a first direction and thereafter a second change (c) thereof is produced in the other direction. The switching of the electronic interrupter (7) into the conducting condition occurs when the charge of the capacitor reaches a threshold value during the second change of the charge. That threshold value is modifiable by a regulating value that depends at least in part on the engine speed.

Abstract: An input stage for an ignition control circuit is provided for producing an output signal from a comparator which switches the primary current circuit of the ignition coil in dependence on a control signal in which the control signal causes alternate switching of two current multipliers, a first charging current determined by a charging resistance and a second charging current determined by the first current multiplier charges a first capacitor, a third charging current derived from the second charging current charges a second capacitor, a first discharge current determined by a discharging resistance and a second discharge current determined by the second current multiplier discharges the first capacitor, a third discharging current derived from the second charging current discharges the second capacitor and a comparator compares the voltage at the second capacitor with a reference voltage to produce an output signal for switching the primary current of the ignition coil.

Abstract: An ignition system for the internal combustion engine is provided wherein a retard start timing and a conduction start timing are provided on the basis of an electrical signal produced from a pick-up coil. An ignition timing is provided at a time point following a retard time determined from the retard start timing in accordance with the engine operating conditions while advancing the retard start timing in accordance with the engine r.p.m. Before the lapse of a cut-off period of the ignition coil current required for producing a required ignition pulse, the cut-off state of the ignition coil current is maintained and the conduction start timing is prevented from advancing before the time point immediately following the lapse of the cut-off period.

Abstract: An internal combustion engine contactless ignition system of the supply voltage variation compensation type in which the length of time an ignition coil is energized is controlled by an input transistor in response to an alternating current signal synchronized with the rotation of an engine and the operating level of the input transistor is automatically shifted in response to variation of the voltage of a power source, further comprises an inverting transistor having a base connected to the collector of the input transistor, an emitter connected to one end of the power source through a common emitter resistor and a collector connected to the other end of the power source through collector resistors and a Zener diode whereby an ignition coil energization controlling power transistor is controlled through the inverting transistor.

Abstract: An ignition system which is responsive to timing signals generated in timed relationship to the operation of an internal combustion engine for providing firing spark to operate the engine. The system uses two capacitors to provide an adaptive dwell system wherein the percent of time that ignition coil current is limited at a fixed magnitude is made variable with respect to the engine rpm.

Abstract: In addition to a first storage circuit in which a sawtooth wave is generated for comparing the ramp voltage with a threshold voltage that is caused to vary with engine conditions, particularly engine speed, for determining when the interruptor switch of the primary circuit of an ignition coil is closed to begin buildup of current therein, an auxiliary storage circuit is provided for generating an auxiliary signal within the duration of which the sawtooth wave of the main charging circuit must return to its starting condition, and another pulse signal present during all but an initial portion of the auxiliary signal for rapidly returning that sawtooth wave to its beginning a new beginning, thus making a longer part of the ignition cycle available for variation of the duration of the period during which the interruptor switch is closed to allow buildup of current in the ignition coil.

Abstract: An ignition energy control method and system such that a high ignition energy is supplied to the spark plugs only while the engine is operating under an unstable condition. The unstable engine operating condition is determined by detecting the difference in the maximum engine speed within a predetermined crankshaft revolution angle or by detecting the low-frequency vibration generated by the engine. The ignition energy is controlled by calculating an appropriate pulse-width of an ignition signal or by changing a high voltage generating plasma within the cylinders. The ignition energy control system according to the present invention comprises a crankshaft angle sensor or a low-frequency vibration sensor, a calculating and storing means, and an ignition system including a plasma generating power supply where necessary.

Abstract: A supply-voltage-compensated contactless ignition system for internal combustion engines, which includes input transistor operable in response to an engine ignition signal so as to control the operation of a power transistor to control the energization of an ignition coil with the operating level of the input transistors being varied with variation in the supply voltage, further includes a current mirror circuit having first and second current shunt paths including first and second transistors which are connected in parallel with a voltage clamping device such that the each current path substantially the same amount of current when the supply voltage is normal and that one of the current paths shunts a current increased over that of the other in response to a rise of the supply voltage beyond a predetermined value, and includes a shunt device for shunting the increased current to the input transistors.

Abstract: To provide sufficient ON-time to store adequate electromagnetic energy in an ignition coil (5, 6), even under high-speed engine operations, in which the ON time of an electronic ignition breaker switch (7, 8) and the OFF or ignition instant thereof is determined by a signal (U16) derived from an a-c type signal source, a signal processing stage (32) is interconnected between the signal source and the ignition signal triggering stage (9) which includes an integrator (27) which commences to integrate when, after an ignition event, the voltage from the signal source (16) has dropped to a predetermined level (Up), the integrated voltage being compared with a threshold level (Uc) to start the ON period of the switch (7, 8) even though the voltage from the signal source (16) may be below that reference level (Up), the output from the integrator and from the signal source being connected to an analog OR-gate (21, 30, 31, 33) which passes the higher one of the two signals, the integrator (27) thereupon being reset to

Abstract: The circuit determines which cylinder is to be fired and continually updates the determination so that the circuit recovers immediately from any false detect and responds to any change of engine condition. The dwell timing is derived from sensors adjacent the flywheel and, to achieve the widest possible range of advance angles, the use of certain sensor-derived signals is delayed until after spark.

Abstract: A circuit to be utilized in combination with an ignition system which is responsive to a start signal supplied thereto for maintaining the ignition system in a start mode of operation while starting of the internal combustion engine is controlled by the ignition system. The circuit is responsive to termination of the start signal to provide transitioning of the ignition system to a run mode of operation only during the current ramping period when the ignition coil of the ignition system is being charged prior to the end of a firing cycle when the coil is discharged to provide spark to operate the engine. Start retard and transitioning of the system from start to run modes is provided utilizing a single capacitor.

Abstract: Timing increment signals produced by an engine driven tachogenerator are used for controlling both ignition timing shift and the dwell time of the interruptor switch of the ignition system. Counting of increment pulses by the ignition coil primary current rises to a predetermined value (Io) are measures a dwell time fraction and provides a count result that goes into a computation of which the result measures the duration of a counting of increments between the end of one dwell time and the beginning of the next. For better dynamic behavior the count value representing the dwell time fraction (.beta.t) is corrected in a calculating stage (16-18) by a factor which represents the proportional change in the duration of an increment signal (such a signal at a fixed point in the cycle to the most increment signal).

Abstract: Circuit for generating a trigger pulse delayed within a period of a periodical motion of variable periodic time, the phase lag relative to a zero phase being dependent on the periodic time and other parameters, a zero pulse and angle pulses starting at zero 5 phase being generated, the pulse frequency being inversely proportional to the periodic time, the angle pulses being fed into a counter and correcting data being generated within every period during a constant-time window. The technical problem the invention relates to is to design the circuit so that a single sequence of angle pulses may be evaluated and no control pulses are necessary except a reference pulse for defining a reference phase. According to the invention the following solution to the problem is proposed: during a constant-time window the angle pulses are varied under control so that each single pulse may be duplicated, counted normally, or suppressed.

Abstract: The occurrence times of discharges of a multi-cylinder internal combustion engine of an automotive vehicle having a transmission and sources for deriving signals indicative of: (a) the engine being cranked or operating normally, (b) the transmission being in high or low gear, (c) engine speed, and (d) the values of parameters determining engine load are controlled by a computer responsive to the signals. The computer includes a read only memory having tables for storing signals with values indicative of spark advance and dwell angle as functions of engine load and engine speed for the engine being cranked, operating normally, the transmission being in high and low gear. The computer responds to the signals of the sources for selecting from the tables stored signals having values indicative of spark advance and dwell angle corresponding with the conditions indicated by signals (a), (b), (c) and (d).

Abstract: A spark coil control device for an internal combustion engine with several cylinders, including a target with a given number of protrusions distributed regularly around its periphery which is rotating with the crankshaft, at least one fixed-position primary element associated with the target, an ignition coil, a rotating spark distributor for inducing explosions within the various cylinders of the engine is succession by the intermediary of the associated sparkplugs, a stage for processing of the data signal retrieved by the position primary element which inter alia provides a synchronization signal and a speed of rotation signal, an electronic ignition advance calculator which at a first output provides a gross numerical value for ignition advance angle and, at a second output, a gross numerical value for the angle of conduction of the coil, and a power stage for commanding the ignition coil.

Abstract: An off-time control circuit drives an output transistor connected in series with a primary winding of an ignition coil while controlling the off-time in each ignition period so that the ratio T.sub.i /T between the period of time T.sub.i, during which the level of primary current supplied to the primary winding of the ignition coil attains a predetermined setting, and the ignition period can be maintained constant. The output from a current detecting resistor connected to the primary winding is applied to a rising time detecting circuit which detects the rising time of the primary current from the current supply starting time to the time of attainment of the predetermined setting. The off-time control circuit controls the starting time of power supplied to the output transistor depending on the output from the rising time detecting circuit.

Abstract: A dwell angle control has three counting devices for detecting acceleration. In a first UP/DOWN counter (17), the count in one direction takes place throughout the time the current in the primary circuit of an ignition coil (25) exceeds a current threshold value (I1). The count in the other direction is constant with respect to time. The counts on the first counter are taken over into a second UP/DOWN counter (11) in response to the input signal, the counting direction also being determined by the input signals. When the count in the second counter (11) reaches an adjustable trigger threshold value, the closure time is initiated, the actual ignition time being fixed by an edge of a sensed signal, or the edge of the signal from an ignition computer. The adjustable trigger threshold value is advantageously determined by a third UP/DOWN counter (12) which is set to a fixed value (X) by an edge of the sensed signal and whose counting direction is also determined by the sensed signals.

Abstract: A contactless ignition system for an internal combustion engine comprises a signal generator generating an AC signal synchronously with the rotation of the engine, a resistor detecting primary current supplied to an ignition coil, a circuit detecting the rising time of the primary current until the primary current attains a predetermined level, and a circuit producing a signal proportional to the rotational speed of the engine. On the basis of the signal indicative of the rising time of the primary current supplied to the ignition coil and the signal proportional to the rotational speed of the engine, an off-time control signal for controlling the off-time of the ignition coil is generated in which the ratio between the duration of the primary current supplied to the ignition coil, being maintained at the predetermined level, and the ignition period is maintained constant. The off-time of the ignition coil is controlled only when the rotational period of the engine is shorter than a predetermined setting.

Abstract: Ignition timing is controlled to provide a fixed advanced timing based on a standard angle signal derived from a standard angle sensor during low engine running speeds such as starting and idling engine timing advance is varied during higher running speeds based on a time duration elapsing from the timing of the standard angle signal derived from the sensor thereby, engine starting performance and idling stability are substantially improved.

Abstract: An ingition system for internal combustion engines has dwell angle control apparatus for controlling the switching times of an electronic switch (21) in the primary circuit of an ignition coil (22) in dependence on the signals of a rotating sensor (10) or an ignition computer (11). Specifically, speed dependent counting values are periodically generated in a counting apparatus (13) each being counted down in a further counting apparatus (14) controlled by an edge of the sensed signal or a computed signal. Upon reaching a presettable triggering counting value, the electronic switch (21) is closed (start of dwell period). This triggering value is set by periodic up and down counting processes in a control counter (17) the upwards counting being constant with respect to time and the count-down process being determined by the length of time of current flow above a settable current value through the ignition coil (23).

Abstract: A switching transistor (7, 9) is serially connected with the primary (5) of an ignition coil; current flow therethrough is controlled from an a-c signal generator (16) with respect to an ON threshold level (Ue) to store electromagnetic energy, and an OFF threshold level (Ua) to generate a spark; a variable conductivity circuit (26) controlled from a sensing resistor (8) modifies the response level of the threshold switch (13) with respect to the null or cross-over level of the applied signal. To prevent excessive current flow under idle-speed conditions, in accordance with the invention, the ON threshold level, at least, of the switch is shifted by introducing an auxiliary bias voltage derived from an auxiliary capacitor (36) and connected (37, 38) by the signal source through a diode (38) which prevents application of an auxiliary bias voltage to the threshold switch (13) under extremely low, e.g.

Abstract: A system for controlling the primary current of an ignition coil using a constant current signal having a calculation device to produce a signal for controlling the ON period of the primary current of the ignition coil, wherein a correction calculation device is provided to calculate the corrected value of the constant current period of the ignition coil.

Abstract: The values of dwell and ignition timing signals from which ignition dwell and spark timing are provided are controlled to minimize power dissipation in an electronic ignition system and to ensure that adequate dwell times are provided during engine acceleration conditions and large advance angle increases. The dwell signal is increased from a static dwell value during steady state engine operation to a higher value in response to sensed engine accelerating conditions and the change in the spark advance between ignition events is limited to ensure that an adequate dwell period is provided.

Abstract: An engine control method and apparatus generally applicable to those control systems of the engine such as an ignition system, fuel injection system, etc., which are controlled to optimum operation in accordance with the engine operating conditions. In this method, an operation starting timing and an operation ending timing of the control system, e.g., in the case of the ignition system, an ignition coil energization starting timing and an ignition timing (an energization ending timing) are computed at each of predetermined computing cycles, and the latest computed ignition timing, for example, which is computed after the coil energization has been started, further taking into consideration the actual coil energization timing and a minimum required energization period is compared with an ignition timing computed in the preceding computing cycle, and a corrective computation of the latest computed ignition timing is carried out depending on the result of the comparison to obtain an optimum ignition timing.

Abstract: Digital dwell circuitry for a spark and dwell ignition control system is disclosed. Maximum advance and reference sensors are utilized to produce pulse transitions which determine positions of maximum and minimum possible advance for spark ignition with respect to the position of the engine crankshaft. For each maximum advance sensor pulse transition a main counter starts a sequential running count of speed independent clock pulses wherein the maximum count obtained by the counter is related to engine crankshaft speed. The running and maximum counts of the main counter are utilized by dwell circuitry to determine the time prior to the next maximum advance pulse at which spark coil excitation should occur. The main counter running count also determines several inputs to a read only memory (ROM) circuit whose output controls a rate multiplier.

Abstract: In order to reduce the amount of ignition energy supplied to an ignition coil during low speed operation of the engine, an electronic circuit is provided to regulate the open time of the ignition circuit to be constant in an upper engine speed domain and to then obey a predetermined characteristic in the mid-range. The mid-range control is gradually made ineffective at lower engine speeds where the open ignition interval is determined by speed as measured by the duty cycle of the engine ignition transducer. The change of characteristics is obtained with the aid of a control voltage source which generates a speed dependent control voltage causing the discharge time of a capacitor to be extended at low engine speeds and causing the termination of the open time of the ignition to be determined by the transducer output signal.

Abstract: A disk mounted on a rotating shaft of an internal combustion engine has a signal generating segment which causes generation of a pickup signal having a leading and a trailing edge. The two different edges control different processes, as for example ignition processes of different ignition coils, fuel injection processes, or ignition processes during normal and starting operation. A basic counting value is counted down between two sequential edge signals in a counter. This is a speed-dependent value from which different countdown values for the next cycle are computed. To allow adjustment of the angle at which one process takes place without simultaneous adjustment of the angle at which the other process takes place, one or both of the edges of the segment from which the control signals are derived have slanted portions, so that movement of the pickup relative to the slanted portions will effectively cause a change in the angle at which a process is initiated.

Abstract: In an electronically controlled ignition device for a combustion engine, firstly an ignition timing and an energized angle of an ignition coil are calculated with response to running condition of the engine, secondly a non-energized angle of the ignition coil is calculated based on the result of the above calculation, thirdly the number of pulses generated with response to the angle of revolution of the engine is counted from the preceding ignition timing, so as to start the energizing of the ignition coil when the result of the above count coincides with the result of the above calculation of non-energized angle, and fourthly the number of pulses generated with response to the angle of revolution of the engine is counted from a reference position of revolution at which a reference pulse is generated by the revolution of the engine, so as to cut off the energizing of the ignition coil when the result of the above count of pulses coincides with the present ignition timing.

Abstract: To provide a composite output pulse in which the pulse length increases relative to the angle of rotation as the speed of a rotating element, typically a rotor coupled to an internal combustion engine increases so that the closing angle of current supply to an ignition coil increases with speed, a magnetic element or other marker on a rotor is exposed to two transducers, one of which provide a signal which is position dependent and the other one a signal which is speed dependent. The output signals from the transducers are combined. The position dependent transducer provides an output pulse of fixed pulse length, relative to angle of rotation of the rotating element, the speed dependent pulse providing output pulses of variable pulse length which overlap with the pulse of fixed pulse length.

Abstract: A time period during which current is conducted through a primary winding of an ignition coil of an internal combustion engine is calculated in response to signals corresponding to an actual rotational speed of the engine and the magnitude of a power supply voltage which is applied to the primary winding, respectively. A time for initiating the primary winding current is controlled in accordance with the calculated time period. Such current is conducted for a maximum period of time, which is determined in response to the magnitude of the power supply voltage, so as to avoid excessive heat build-up in the ignition coil. The rotational speed of the engine is determined by counting clock signals during time intervals which correspond to predetermined angular segments of rotation.

Abstract: Digital dwell circuitry for a spark and dwell ignition control system is disclosed. Maximum advance and reference sensors are utilized to produce pulse transitions which determine positions of maximum and minimum possible advance for spark ignition with respect to the position of the engine crankshaft. For each maximum advance sensor pulse transition a main counter starts a sequential running count of speed independent clock pulses wherein the maximum count obtained by the counter is related to engine crankshaft speed. The running and maximum counts of the main counter are utilized by dwell circuitry to determine the time prior to the next maximum advance pulse at which spark coil excitation should occur. The main counter running count also determines several inputs to a read only memory (ROM) circuit whose output controls a rate multiplier.

Abstract: The previous ignition timing is used as a starting point for repititive ignition cycles to define the primary coil current flow starting point, in order to secure a sufficient current flow duration for the primary coil current that is supplied to an ignition coil to thereby prevent a shortage of ignition energy. An arithmetic circuit including a central processor produces data representing the duration between the previous ignition timing and the primary coil current flow starting point. A counter starts this counting operation from the previous ignition timing. The primary coil current feed to the ignition coil starts at a time when the contents of the counter are coincident with the result of the processor produced data.The data is obtained by subtracting a necessary primary current flow duration or time from the interval between the previous ignition timing and the present ignition timing.

Abstract: An ignition system for an internal combustion engine. The ignition system comprises a pulser for generating positive and negative output pulses responsive to the rotation of the engine, a DC power source and an ignition coil having a primary coil connected across the DC power source via a controllable current switching element. The system further comprises a control circuit for controlling the switching element which includes triangular wave generators for generating different triangular wave signals in response to the positive and negative output pulses of the pulser, respectively, a first comparator for comparing a first output signal of one triangular wave generator with a signal which is formed by multiplying a second output signal of the other triangular wave generator by a constant and adding it with a fixed voltage, and a second comparator for comparing the second output signal with a signal which is formed by multiplying the first output signal by a constant and adding it with a fixed voltage.

Abstract: A transistorized ignition apparatus for driving plural ignition coils of an internal combustion engine comprising two power transistor circuits, each having a power transistor, and a pick-up coil for generating an ignition timing signal synchronized with the rotation of the engine. A wave-form shaping circuit receives the ignition timing signal and determines the conduction period of the power transistors, including the conduction starting point thereof. Two driver circuits, which are provided for respective power transistor circuits, produce driving signals thereto on the receipt of an output from the wave-form shaping circuit. Each power transistor circuit has a current limiter circuit which decreases the base current of the power transistor depending on the amount of the current flowing therethrough. The currents through the power transistors, therefore, are restricted to respective maximum values and the operations thereof are drawn into the non-saturation region.

Abstract: Electronic signal processing circuitry particularly useful in the ignition system of an internal combustion engine is disclosed. A pulse generator includes a crank-shaft position sensor supplying periodic position pulses to a bi-stable flip-flop circuit controlling a dual slope integration circuit. The integration circuit establishes a dual ramp time varying voltage signal at one input to a comparator for comparison with a reference voltage source which is established at the second input. At equality, an output pulse is initiated at the output of the comparator and this pulse is also used to change the logic state of the flip-flop. A hysteresis circuit responds to the initiation of the output pulse by modifying by a predetermined amount, the reference voltage level at the comparator. The duration of the output pulse is thereby made selectable and independent of variations in the period of the sensor pulses.

Abstract: The AC signal generator furnishing the basic control signal for ignition timing is a Hall generator the flux through which is gradually increased while the crankshaft of the engine rotates through a predetermined angle of rotation. The Hall generator is part of a magnetic circuit which also includes an air gap. The change in flux is accomplished by rotating a tapered magnetically conductive member through the air gap. The output of the Hall generator is applied through a linear amplifier to a threshold circuit whose output controls an electronic interrupter switch connected in series with the ignition coil.

Abstract: An ignition control system typically used with an automobile engine provides tight feedback control on engine timing. An integrator produces a waveform which is typically dual-slope in response to a timing signal supplied by a sensor responsive to rotation of a distributor. A dwell-control circuit produces a dwell-control reference signal which varies with the integrator waveform voltage at low engine speed. A comparator generates an output drive-control signal when the integrator waveform voltage equals or is less than the dwell-control reference voltage. An output drive circuit produces an activation signal in response to the drive-control signal to activate an output drive circuit which then supplies an ignition signal to an ignition coil. A feedback loop between the output drive circuit and the output drive-control circuit causes the output drive circuit to stabilize at a selected state such as a specified output current level.

Abstract: A novel electronic control circuit which may be used in different types of electronic engine control systems is disclosed. Illustrative usage in various types of electronic spark timing control systems contemplates 4, 6, and 8 cylinder engine configurations as well as single or multiple pick-ups. The circuit is intended for fabrication as an integrated circuit device to provide a low-cost unit which is advantageous in mass production usage.