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.

Abstract: An ignition system for a multicylinder engine comprising a magneto having an igniting exciter coil to induce an AC voltage in synchronism with rotation of the engine; ignition coils having secondary coil portions respectively connected to ignition plugs for cylinders of the engine, to supply a high voltage to the respective ignition plugs; and a primary current controlling semiconductor switch connected to the igniting exciter coil in parallel therewith to be turned on in advance of respective igniting positions of the cylinders so that a current flows through the semiconductor switch.

Abstract: To permit use of integrated circuits in solid-state ignition control systems in which the current through the primary of the ignition is pulsed when a predetermined level is reached, a threshold switch which has switching hysteresis is connected to control conduction of an auxiliary semiconductor connected in parallel with the ignition coil, to control the auxiliary semiconductor to become conductive when the current through the coil rises above a predetermined first threshold level to thereby shunt the primary thereof or to block the auxiliary semiconductor switch when the current through the coil drops below a predetermined second threshold level and thereby removes the shunt from the primary of the ignition coil and permits current flow from a power source thereto to ensure, reliably, alternate opening and closing of the main controlled switch, typically a transistor, in series with the coil and the auxiliary controlled switch.

Abstract: A distributorless ignition system has an alternating current power source for providing power to fire the igniters. The alternating current power source is coupled through a capacitor to a plurality of ignition transformers, one transformer for each igniter. Each transformer has an electronic switch in its primary winding circuit initiated by independent logic means for each switch. A timer, driven by the engine, triggers one logic circuit at a time so that only one electronic switch and consequently one igniter is fired at such one time, maintaining the other logic circuits and electronic switches quiescent during such firing. The system has short lengths of high tension wires connecting each ignition transformer secondary winding to its respective igniter.

Abstract: An alternating current power source which is generally used to feed an ignition transformer primary winding may be electronically controlled so as to rapidly activate and deactivate the power source for each ignition cycle. An electronic switch intermittently interrupts current flowing in the primary winding and in the output circuit of the power source. Such electronic switch is made operable by virtue of the peak excursions of the alternating current, thus supplying the necessary collector potential to such switch during each firing cycle of the system. Such control system can have these type of controls in the collector circuit of the power source, the emitter circuit of such power source, the DC power input circuit for such power source, or in the output circuit of the power source's output transformer. A capacitor in series with the output circuit of the power source and with the primary winding enables current to be transferred out of the power source to such primary winding.

Abstract: In a flywheel magneto ignition system, opposite terminals of the primary winding are respectively connected with the collector and emitter terminals of a transistor device. A biasing coil, inductively coupled with the magneto armature core, has its terminals respectively connected to the transistor base and emitter terminals to bias the transistor on during an interval terminating at the time of ignition. An SCR, non-conductive during said interval, is connected for short circuiting the biasing coil. A trigger coil, connected with the SCR gate through a zener diode, provides gating current for the SCR at the time of ignition. A diode in series with the biasing coil and the base-emitter junction of the transistor ensures fast transistor turn-off.

Abstract: To provide for electronically controlled spark advance of the ignition instant in a transistorized magneto ignition system, the ignition instant is controlled by a threshold switch responsive to voltage generated by the magneto, the threshold being connected to a timing circuit which includes a resistance network therein, the resistance value of which is variable with respect to operating speed of the engine. The resistance network includes a R/C timing circuit which, as the speed of the engine increases, presents a respectively smaller resistance value to rapidly recurring signals from the magneto so that, effectively, the resistance value of the timing circuit controlling current flow through the threshold circuit is decreased, causing a shift in the ignition instant, the circuit being arranged to advance the spark with respect to upper dead center (UDC) position of the piston of the engine.

Abstract: This disclosure relates to a pulse generator for triggering successive energy discharges such as in automotive or other ignition systems and the like, which generator comprises a magnetic circuit a portion of which is interrupted by a conductive vane the position of which controls the production of the pulses and at least one winding encircling a portion of said magnetic circuit, means connecting said winding to the output of an amplifying means, said components connected to produce as negative feedback at the input of said amplifying means the total voltage across said winding; the magnetic circuit and electronic circuitry connected thereto being so arranged as to minimize the number of components which must be placed in close physical proximity to the rotating vane, generally in the distributor of the engine, and to also minimize the number of interconnecting leads from the vane location to the balance of the ignition system, thus producing a small, inexpensive and highly accurate pulse generator.

Abstract: In an ignition system having a magneto, the ignition timing is advanced when the engine speed exceeds a predetermined speed, by abruptly changing the voltage applied to the base of a transistor having an emitter-collector circuit connected in series with the primary winding of the ignition coil. The change in base voltage is such that the primary current flowing before the ignition time is decreased, increasing the primary voltage and thereby advancing the ignition time when the speed of the engine reaches the predetermined speed. The abrupt change is generated by opening or closing a switch which connects a resistor in series or parallel, respectively, with a resistor connected to the base of the transistor. The speed dependent switch may be a transistor whose conductive or non-conductive state is determined by the charge and discharge of a capacitor which, in turn, varies as a function of engine speed.

Abstract: An electronic control circuit incorporated with an AC type ignition system which employs a high-frequency continuous-wave oscillator. The system includes a control winding on a transformer that has a high voltage spark signal output winding. There is a transistor in series with the control winding, to switch on and off a circuit that controls the starting and stopping of the oscillator. And, there are a pair of time delay circuits which produce delay times that are inversely proportional to the speed of an internal combustion engine that uses the ignition system. These time delay circuits may be connected so as to use only one of them. Or, they may be connected in series, so that a desired step timing change may be introduced (or not) upon demand.

Abstract: An electronic magneto ignition for internal combustion engines has a permanent magnet mounted on the engine fly wheel and rotating therewith. A magnetic field coil has a primary winding and a secondary winding in which ignition current and ignition voltage, respectively, are produced during the passage of the permanent magnet. A switching transistor is connected in parallel with the primary winding and in parallel with a diode poled opposite to the emitter-collector path of the transistor. An electronic control circuit blocks the switching transistor at the desired ignition time so that the primary circuit is interrupted and the high voltage for the combustion of the fuel is produced in the secondary winding. In the electronic control circuit, a parallel circuit consisting of a first control coil, which has a resistor in series therewith, and a thyristor is connected from the base to the emitter of the switching transistor.

Abstract: In a contactless ignition control system having a dwell time control circuit for an internal combustion engine, there is provided a speed responsive bias voltage circuit, a bias voltge switching circuit and a wave shaping circuit. The speed responsive bias voltage changes the switching level of the wave shaping circuit, thereby elongating the dwell time of the current flowing through an ignition coil.In the dwell time control, when the ignition timing comes, the bias voltage switching circuit prevents application of the speed responsive bias voltage so that the ignition timing is made irrespective of the speed responsive bias voltage.

Abstract: The present invention discloses an ignition system for internal combustion engines. The ignition system is particularly applicable to such engines including a magneto.The ignition system includes a semi-conductor ignition circuit in which a first transistor has its collector-emitter conduction path connected in series with the primary winding of an ignition coil assembly. A resistor is connected between base and collector of the first transistor to permit it to conduct. A control circuit connected between the base of the first transistor and the primary winding, turns the first trnasistor off when it is desired to interrupt the primary winding current.The ignition system also includes a magneto ignition coil assembly which has a low inductance primary winding having a relatively low number of turns. The coil assemblies of the present invention are generally unsuitable for use with conventional mechanical breaker points.

Abstract: This invention relates to an ignition system which produces a continuous sinusoidal wave at audio frequency in order to produce a continuous spark discharge during certain times, at the spark plugs and is usable in any form of gasoline burning internal combustion engine using an ignition system. It can be fitted to any type or size of automobile or industrial engines and includes a power transistor oscillator circuit with a solid state high voltage generator switched with a switching transistor and actuated by the make and break circuit operated by the breaker points but independently of ignition timing. The spark discharge causes ionization between the spark plug points and produces ozone thereby improving the quality and speed of burning and, because of the more efficient operation, decreases noxious emissions from the exhaust system.

Abstract: An electronic ignition control device includes a voltage step up coil with its primary winding in series with an electronic contact breaker. The contact breaker is directly controlled by a first monostable circuit which is connected to be triggered by signals from an ignition signal generator. A comparator receiver a voltage signal from a coil current transducer and compares this with a fixed voltage level, producing a square wave of duration dependent on the excess of the voltage signal above the fixed voltage level. An integrator integrates the output of the comparator and provides a pulse duration control signal to the first monostable. A second monostable triggered by the generator also produces a square of predetermined duration. A current limiting circuit is connected to limit current in the primary winding. The first and second monostable circuits and the current limiting circuit all have their outputs connected to an OR gate which controls the primary current.

Abstract: The voltage in the secondary of an ignition coil is prevented from reaching an amplitude at which a spark might be created by a Zener diode connected in parallel with the series transistor acting as a switch which interrupts the current through the primary winding of the coil. Upon breakdown of the Zener diode, the series transistor is switched to the conductive state briefly, thereby preventing further voltage build-up in the secondary. When the engine is in operation, a transistor which forms part of a voltage divider is switched to the conductive state, connecting the voltage divider between the secondary winding and the Zener diode. The voltage divider is so dimensioned that the Zener diode will respond to a voltage slightly less than the breakdown voltage of the emitter-collector circuit of the series transistor, but higher than the voltage required for creating a spark.

Abstract: A circuit for controlling the current supplied to an ignition coil is usable in conjunction with an electronic ignition. In one embodiment a transistor is connected in shunt with the input of a current amplifier and has a control electrode connected to a voltage divider a portion of which is in series with the coil, so that the transistor is responsive to both battery voltage and coil current. Excessive voltage or coil current causes the transistor to conduct thereby lowering the input signal to the current amplifier and reducing the coil current.

Abstract: A spark plug igniter with an auxiliary power source, in which the auxiliary power source is a DC-DC converter including a feedback loop. A high voltage induced in a secondary winding of an ignition coil and a DC voltage generated by the converter are additionally supplied in the same polarity to a spark discharge gap. The feedback loop of the DC-DC converter comprises a feedback winding, a rectifier connected to the feedback winding through a reactance element, and means for connecting the DC output of the rectifier in series to the DC power source of the converter in the same polarity.

Abstract: A single pick-up coupled to sense engine crankshaft position can be utilized for both starting and running of the engine in an electronic spark timing advance control system. During starting, pulses from the pick-up are coupled via a zero crossing detector to the output ignition stage to cause spark plug firing at an essentially constant firing angle at or just slightly in advance of piston top dead center position. During running, the pulses from the pick-up reset, via a reset circuit, an integrator circuit so that a sawtooth waveform representative of engine crankshaft rotational position is developed. A desired timing signal derived from one or more parameters useful in controlling the time of ignition firing is compared against the sawtooth reference waveform and when a predetermined relationship between the two is attained, the ignition is fired. Should this predetermined relationship not be attained during a cycle of the sawtooth, the reset signal from the reset circuit forces ignition firing.

Abstract: A multi-strike spark discharge system which is combined with an internal combustion engine to produce a plurality of high voltage discharges across the spark gap of the engine. A timing signal associated with the engine is treated and used to actuate a duration control circuit which in turn actuates a repetition rate control circuit thereby controlling the duration and frequency of the discharges across the spark gap. At low rpm the repetition rate control apparatus provides several multi-discharges which enhances the combustion process and improves the operation of the combination.

Abstract: To provide for gradual turn-off of an ignition coil current control transistor, a control capacitor which provides turn-off current has its charge state changed gradually by means of an auxiliary transistor so connected to the capacitor that the conduction of the emitter-collector path of the auxiliary transistor is gradually changed, the main switching transistor being connected to and controlled by the auxiliary transistor and likewise changing gradually from conductive to blocking state in dependence on the gradual change in conduction of the emitter-collector path of the auxiliary transistor to prevent rapid turn-off of the main switching transistor and hence an undesired pulse at the secondary of the ignition coil which may induce continued operation of the internal combustion engine even though the ignition has been turned off.

Abstract: An internal combustion engine spark ignition system includes a transducer and a transducer circuit which coact to produce a rectangular pulse for each spark required. The leading edge of this pulse controls an input transistor which controls an output transistor through an intermediate transistor. The output transistor in turn controls an ignition circuit controlling the current through an ignition coil. The coupling between the intermediate and output transistors includes a resistance chain to points in which two timing capacitors are connected. At high speeds the circuit provides a fixed coil current duty cycle with a relatively short off time, whereas, at low speeds the duty cycle is determined by the length of the pulses from the transducer circuit giving a relatively long off time.

Abstract: An opto-electronic ignition system for an internal combustion engine in which radiation falls on to and is cut off from a photo-transistor in timed sequence with the engine, and in which between the photo-transistor and the primary winding of the ignition coil there is a plurality of switching Darlington pairs, each Darlington switching in inverse relation to its neighbor, and the first Darlington switching in inverse relation with the photo-transistor. The circuit is designed so that it will reliably operate in engine compartment temperatures above 125.degree. C.

Abstract: A circuit arrangement for controlling the energization and de-energization of a coil comprises a switching transistor for controlling the coil and which is not provided with protection against avalanche breakdown, a resistor being provided in parallel with the base-emitter path of the switching transistor to prevent overload of the switching transistor during avalanche operation.

Abstract: An ignition system for an internal combustion engine having an AC generator compriss an ignition coil energized by an output from the generator. At an angle in advance of ignition timing, a first thyristor connected across the generator output terminals is turned on to permit a short-circuit current therethrough. A capacitor is charged by an output from the generator, and is discharged through a second thyristor which is triggeed at the ignition angle. The discharge current is reversely applied to the first thyristor and the first thyristor is turned off. Interruption of the short-circuit current through the first thyristor leads to a large current through the primary of the ignition coil, causing a high voltage in the secondary with resultant spark in the ignition plug.

Abstract: A variable dwell ignition system comprising a circuit responsive to changes in engine RPM for causing the dwell time of the ignition system to be varied accordingly. The circuit is adapted to be connected to a sensor coil to receive ignition timing signals developed thereacross which are generated in timed relationship to the engine operation. The circuit provides for changing the direct current (DC) level about which the ignition signals are generated such that a threshold level is varied. As the threshold level is varied the dwell time of the system is varied respectively.

Abstract: An ignition circuit for use in an internal combustion engine comprises a magnet generator mechanically connected to a crank shaft of the engine. A first transistor is turned on and off by an alternating voltage signal from the magnet generator. A power transistor forms a closed circuit in cooperation with a high voltage transformer and a current source. The power transistor is controlled by a control signal from the first transistor so as to form a primary current which is abruptly cut off. The transformer induces a high voltage which is supplied for a spark plug in response to abrupt interception of the primary current. A delay element composed of a resistor and a capacitor is connected to a base of the first transistor.

Abstract: The proper operation of the ignition system of an internal combustion engine is determined by a visual test indicator which is built into the ignition circuitry. The indicator is energized whenever a H.V. pulse is generated in the secondary circuit. Failure of the indicator to light shows an ignition malfunction. The system is applicable to both point contact and electronic ignition systems.

Abstract: The output signal induced in an electromagnetic pickup and having a frequency corresponding to the rotational speed of an internal combustion engine is applied to the input of an input transistor. The output of the input transistor is connected to the input of a power transistor having its output connected in series with the primary winding of an ignition coil to turn the power transistor on and off in accordance with the output signal of the electromagnetic pickup and thereby switch on and off the current flowing in the primary winding. A DC bias voltage corresponding to the output signal of the electromagnetic pickup is applied to the input of the input transistor to change its operating level. This change in the operating level changes the ratio between the "on" and "off" periods of the power transistor, namely, the ratio between the "on" and "off" periods of the primary winding of the ignition coil.

Abstract: An electronic ignition controller using a Hall Effect pickup Device for use in a ballast-resistorless, inductive-type ignition system for an automotive vehicle internal combustion engine and featuring an automatic shut-down timer, which operates to block the energization of the ignition coil if the controller remains in a state of conduction that maintains the ignition coil energized for a predetermined prolonged period of time that is greater than the dwell period or ON time of the coil at engine cranking speeds.

Abstract: The invention discloses an ignition system control circuit which may be mounted within a distributor housing such as is used with internal combustion engines. The ignition system control circuit is coupled to a direct current source and appropriately connected to the primary winding of the high voltage generating coil of the ignition system. Current through the primary of the high voltage generating coil is controlled by a Darlington power amplifier, the conduction and non-conduction of which is appropriately synchronized to the engine. The control circuit includes a constant current source connected to a biasing resistor network of the Darlington power amplifier, and the constant current source supplies the Darlington power amplifier with a value of current to assure saturation of the Darlington power amplifier to allow maximum current to flow through the primary winding of the ignition coil notwithstanding substantial variations in voltage of the direct current source.

Abstract: This disclosure relates to a pulse generator for triggering successive energy discharges such as in automotive or other ignition systems and the like, which generator comprises a magnetic circuit a portion of which is interrupted by a conductive vane the position of which controls the production of the pulses and at least one winding encircling a portion of said magnetic circuit, means connecting said winding to the output of an amplifying means, said components connected to produce as negative feedback at the input of said amplifying means the total voltage across said winding; the magnetic circuit and electronic circuitry connected thereto being so arranged as to minimize the number of components which must be placed in close physical proximity to the rotating vane, generally in the distributor of the engine, and to also minimize the number of interconnecting leads from the vane location to the balance of the ignition system, thus producing a small, inexpensive and highly accurate pulse generator.

Abstract: An ignition system of a current interruption type comprises an a.c. power source and an ignition coil, the primary winding of which is connected to the a.c. power source through a controllable switch element for interrupting the current. The ignition system further includes a control circuit for controlling the switch element. The control circuit functions to actuate the switch element in synchronism with the ignition cycle of an internal combustion engine in dependence upon the output of the a.c. power source thereby to interrupt the primary current in the ignition coil and induce a high voltage in the secondary winding thereof.

Abstract: An electronic ignition control device employs two switch devices (e.g. mechanical contact breakers) operating at different instants to control initiation and interruption of current flow in the primary winding of the ignition coil. The coil current is controlled by an output transistor which is biased to conduct but which is switched off by an input transistor when a spark is required. The input transistor is controlled by the two switch devices so that opening of one switch device initiates primary current and opening of the other interrupts this primary current.

Abstract: A pulse waveform recognition circuit includes an input stage consisting of a tuned circuit tuned to approximately the frequency of a sinusoid to half-waves of which the pulses to be recognized approximate. A transistor is biased to conduct weakly and has its base coupled to the tuned circuit so as to be turned on by a pulse within the band width of the tuned circuit. The transistor drives a monostable multi-vibrator with a frequency dependent feedback circuit which causes the reversion time of the multi-vibrator to decrease as the frequency of triggering increases and which also increases the threshold voltage required to trigger the monostable circuit as this frequency increases. The circuit is used in an ignition system for an i.c. engine.

Abstract: To provide an undistorted square wave output signal under control of a switch subject to contact chatter so that the square wave will accurately reflect the operating instant of the switch, as commanded, regardless of contact chatter, a timing circuit is provided having a timing capacitor and a charge and discharge circuit therefor, connected to a threshold circuit, the threshold circuit response level and the charge circuit of the timing capacitor being dimensioned to cause the capacitor to charge to a level such that the threshold circuit responds only when the switch has changed state, typically closed after interrupting an inductive load, such as the primary of a spark plug, for a predetermined time period as determined by the switch contact chatter characteristics of the switch itself, for example about 0.

Abstract: To provide a sharp voltage pulse to break down the spark gap of a spark plug, an ignition coil is constructed to have two secondary winding portions, one providing a high-voltage output and the other providing high energy level or current output. The high current output portion is connected through a diode to charge a capacitor which is further connected through an additional blocking diode to the spark gap, to which also the high voltage portion is connected, so that the spark gap will be supplied by a circuit common to both winding portions of the ignition coil, the high voltage pulse breaking down the spark gap and the high energy pulse, of lower voltage, however, providing spark energy for an extended period of time after initial breakdown of the gap. Preferably, the system is transistor-controlled, with the ignition instant being determined by a digital counter counting forward and reversely under control of a rotation-pulse transducer coupled to the crankshaft of the engine.

Abstract: To prevent a spurious inductive spark when the master ignition switch of the vehicle is opened with the breaker terminals closed, so that current stored in the ignition coil might cause a spurious inductive voltage pulse, a protective circuit branch is connected in parallel across the primary of the ignition coil and includes an auxiliary semiconductor short-circuiting switch, preferably a thyristor, the conduction of which is controlled to close by an auxiliary control circuit which senses opening of the master ignition switch and permits application of a portion of the inductive current flow to the gate of the thyristor to render it conductive, thus short-circuiting the primary of the ignition coil and preventing an inductive voltage kick which might cause a spurious spark.

Abstract: To prevent generation of a spurious spark at the spark plug if the distributor braker control assembly should have commanded an ignition control transistor to be conductive and when the ignition switch is disconnected under those conditions, thus cutting off power to the ignition control transistor rendering it non-conductive and causing spurious voltage pulses which results in a spark at the ignition, a control path is provided connected to a control transistor for the actual ignition transistor and connected in circuit with the current flow due to the energy stored in the ignition coil to control the emitter-collector path of the ignition switching transistor to continue to remain conductive for a short period of time to drain off the stored energy in the coil, although the main ignition switch has been opened.

Abstract: A monostable multivibrator circuit is disclosed which uses a feedback diode to couple the output signal of the monostable back to one terminal of the timing capacitor and thereby maintain the voltage at this capacitor terminal at a constant level for a duration equal to the pulse duration of the monostable output. A transistorized internal combustion engine ignition system is illustrated which incorporates the diode feedback monostable circuit. A trigger input signal actuates a first transistor switch which creates an abrupt negative transition that is coupled across a timing capacitor and results in turning off a second transistor for a predetermined amount of time. A third transistor monitors and inverts the output of the second transistor and produces an output signal at its collector. This inverted output signal forms the output of the monostable multivibrator and this signal is fed back to one terminal of the timing capacitor by a feedback diode.

Abstract: An inductive spark ignition system for a gas turbine engine in which the switching semiconductor and other components are protected from failure under igniter plug load conditions. The ignition system includes means for positively turning off the switching semiconductor to start a firing cycle and for insuring that the switching semiconductor remains nonconducting long enough to dissipate the energy in the firing circuit. A Darlington transistor is used for switching and means are provided for limiting voltage and current in the transistor pair.

Abstract: The sub-ultrasonic ionization ignition system "PULSAR" changes the present characteristics of combustion in internal combustion engines.

Abstract: A selective threshold ignition circuit adaptable for use in an electronic ignition system for an engine is disclosed. A magnetic pick-up produces an AC signal about a DC reference level which has a frequency related to the rotational movement produced by the engine. A circuit receives this AC signal and produces a corresponding spark timing signal by comparing the AC signal with a DC threshold level. A selector circuit chooses a first DC threshold level for the comparing circuit which is effectively equal to the DC reference level during the period of engine start up. The selector circuit chooses a second DC threshold level which is different from the DC reference level when the engine is running and before the engine has been started. By providing a threshold level equal to the DC reference level during the engine start up mode of operation, an accurate ignition timing signal is produced during this critical period.

Abstract: There is disclosed an ignition system for a multicylinder internal combustion engine which employs a conventional Kettering ignition coil and a pulse generator such as an induced voltage coil operating in cooperation with a magnetic circuit driven in timed relationship to the engine for generating a train of voltage pulses in synchronism wih the engine. The circuit of the invention includes a circuit across a source of electrical energy and the primary windings of the ignition coil with an electronic switch therein and with a high frequency pass filter in circuit between the induction coil and the electronic switch of the primary windings circuit to pass only the high frequency voltage pulses that are responsive to the inflection point of the cyclic voltage induced in the induction coil. The high pass filter is preferably a tuned RC circuit operative to effect pulse shaping of the train of induced voltage pulses to a train of sharp peak voltage pulses of minimal time and duration.

Abstract: A spark ignition engine has a crankshaft speed pulse generator and a plurality of cylinders each cylinder containing a spark plug. Each plug is connectable to a high voltage ignition winding by way of a reed relay. The relays are divided into two groups and, with a periodicity dependent on generator output, a selected relay in each group is closed immediately prior to generation of voltage in the winding and opened when the voltage has been dissipated. Although both plugs connected to the selected relays produce a spark only one of the cylinders contains fuel mixture and, consequently, one one power stroke occurs.

Abstract: An electronic ignition circuit utilizing a magnetic pick-up winding has both ends of the pick-up winding connected by biasing resistor networks to the output terminal of the input stage of the circuit at which a positive going pulse appears when a negative going signal is induced in the pick-up winding. One end of the winding is connected by a diode to the base of a first transistor which controls a second transistor through a capacitor/resistor chain/diode series combination connected between the collector of the first transistor and said one end of the winding. The arrangement ensures that a spark can be produced even at low speed when a small signal is induced in the winding at the instant when ignition is required.

Abstract: In an ignition system wherein an ignition timing signal generated in synchronism with the engine rotation is detected by a detecting transistor and a base current of a power transistor adapted to control a primary current of an ignition coil is controlled by the detected ignition timing signal thereby to generate a high voltage across a secondary side of the ignition coil; the primary current of the ignition coil is controlled by the power transistor not to exceed a predetermined value, a time interval during which the primary current of the ignition coil is restricted to the predetermined value is detected by a change in collector voltage of the power transistor, i.e. an output thereof, and a conduction starting point for the primary current of ignition coil is controlled by the output of the power transistor.

Abstract: An electronic ignition control device for an internal combustion engine includes a power amplifier which controls current through an ignition coil and a triggering circuit for the power amplifier. To protect the power amplifier against damage resulting from being connected to a higher voltage source during starting there is a protection circuit which switches off the power amplifier when an over voltage is detected but allows it to switch on for a very short period when a spark is required. The protection circuit uses conventional logic elements, sensing the output of the triggering means, the output of a delay circuit driven by the triggering means, and the output of an over voltage sensing circuit.

Abstract: An ignition apparatus for an internal combustion engine, wherein the energization time of the primary winding of the ignition coils is maintained constant regardless of the engine revolutions, is provided with reference time signal generator means within the apparatus. The reference time signal thus produced from the reference time signal generator means is compared with an actual energization time, and the time difference therebetween is negatively fed back to the energization time signal generator means, thereby controlling the energization time in such a way as to always approximate the reference time.

Abstract: In a spark ignition system it is possible for a vehicle to stall with the contact breaker closed, and for a transistor or other device in series with the ignition coil to conduct heavily. This problem is overcome by limiting the time for which the ignition coil can be energised.