Abstract: A revolution threshold regulator and/or toggle switch has a first and a second fixed phase source of alternating current having a frequency proportional to the revolution speed of a rotor of an internal combustion engine. A trigger device scans the alternating currents to emit a control signal at a revolution threshold above or below a preset revolution threshold. The trigger device has a timer module which cooperates with one of the alternating current sources through a trigger charge element which can be discharged via at least one discharge path to create a control signal. The trigger charge element, as it discharges, sends a control current through a series Zener diode in a blocking direction to the control signal output.

Abstract: A revolution threshold regulator and/or toggle switch has a first and a second fixed phase source of alternating current having a frequency proportional to the revolution speed of a rotor of an internal combustion engine. A trigger device scans the alternating currents to emit a control signal at a revolution threshold above or below a preset revolution threshold. The trigger device has a timer module which cooperates with one of the alternating current sources through a trigger charge element which can be discharged via at least one discharge path to create a control signal. The trigger charge element, as it discharges, sends a control current through a series Zener diode in a blocking direction to the control signal output.

Abstract: A water-cooled multi-cylinder engine, includes a control system in which an engine revolution number is reduced to a level less than a restriction revolution number on the basis of at least one condition of misfire and fuel stop for all the cylinders of the engine, at a time of an occurrence of an overheat, so as to restrict an increasing of a temperature of the engine. In a case when the engine revolution number is less than the restriction revolution number after the overheat occurs, or the engine revolution number is lowered to be less than the restriction revolution number on the basis of the revolution number restriction control, a specific cylinder is controlled to be stopped by at least one of misfire and fuel stop.

Abstract: An ignition control system is provided, which includes: an engine speed detector (101) for calculating an engine speed according to an engine crank angle signal (100); a current supply start controller (102) for outputting a proper current supply start timing signal corresponding to the engine speed to an ignition coil (5); a current supply finish controller (103) for outputting a proper current supply timing signal corresponding to the engine speed to an ignition coil; an ignition coil controller (104) for controlling supply of power to the ignition coil (5) according to the current supply start timing signal and the current supply finish timing signal; and an overspeed determination device (105) for outputting an overspeed determination signal when determining that the engine speed is in excess of a predetermined limit value. The overspeed determination signal prohibits starting the supply of current, and retards the current supply finish timing to such a degree as to decrease engine torque.

Abstract: A method of operating an engine during an over temperature condition to protect the engine, an information recording medium incorporating a computer program implementing this protection method, and an electronic control module that performs this protection method are disclosed. A torque value representative of an engine generated torque is recorded in response to an engine temperature exceeding a protection temperature threshold. The engine torque is then reduced as a nonlinear function of the temperature signal and the recorded torque value to promote engine cooling.

Abstract: There is provided an engine controller that prevents the engine operation from being continued due to a throttle valve recovery failure. When a throttle lever is in the unoperated state and the engine revolution higher than a set revolution has remained for a set duration, the engine controller decides that the recovery failure of a throttle valve has occurred and performs a control to stop the operation of the engine. This prevents the engine operation from being continued against the will of the operator in the event that the throttle valve fails to recover. When the engine is used as a motor of a vehicle, for example, the running of the vehicle can be stopped, thus assuring a higher safety.

Abstract: A revolution number control system includes ignition timing delay controlling means for delaying ignition timing from the ignition advance amount n at a first prescribed value n2 when the engine revolution number NE is between the first prescribed value n2 and a clutch-on revolution number n4. The first prescribed value n2 is a predetermined revolution number smaller than a preset revolution number and the clutch-on revolution number n4 is the preset revolution number, and the revolution number control system 40 controls the revolution number by operating the ignition timing delay controlling means when a throttle opening sensor does not detect a change in the throttle opening.

Abstract: A control apparatus of a hybrid vehicle is provided capable of protecting the peripheral components of the motor from a voltage generated by regeneration during travelling the vehicle. When the motor control device 5 detects failures of the motor system such as current sensors 13, 15, and 17, voltage sensors 14, and 16, and a failure of the motor 2 (breakage of the winding), the motor control device 5 stops the motor control by turning off the on-state main contactor and by electrically disconnecting the connection between the power drive unit 7 and the battery 3. At the same time, the motor control device 5 outputs a signal about the failure of the motor system to the engine control device 4. When the failure is detected by the motor control device 5 and when the main contactor 11 is in the off state, the engine control device 4 controls the engine such that the engine rotation speed is maintained below 5000 rpm.

Abstract: A vehicle control unit is disclosed which can be coupled between a tachometer sensor and an electronic ignition system on a vehicle. The unit is also coupled to a speedometer sensor to measure the vehicle's speed. The vehicle control unit limits the vehicle speed by modifying the tachometer signal from the tachometer sensor and providing the modified tachometer signal to the ignition system. The tachometer signal is a pulse train which is used by the electronic ignition system to determine ignition timing. The vehicle control unit limits both ground speed and engine speed by suppressing pulses from the original tachometer signal to prevent the combustion of fuel and thereby reduce engine power when the ground or engine speeds exceed predetermined limits. The vehicle control unit is microcontroller-based and preferably includes a logging function and an acceleration sensor. The microcontroller is coupled to the acceleration sensor to detect the peak accelerations experienced by the vehicle.

Abstract: Analog RPM limiting circuit for use with various types of ignition systems, employing a temperature stabilizing transistor Q3(6) configured as a single junction with biasing resistor R1a(7), a transistor Q2(5) used as a voltage threshold as well as a rapid timing capacitor recharging switch with a regenerative loop supplying bias to an associated regenerative capacitor charging switch Q1(4) constituting a mono-stable multivibrator, with a manual switch S1 for selecting timing capacitors for scaling the timing period according to the number of cylinders, and with another manual switch Q2 for selecting timing resistors for user adjustable RPM limit range, and Q1 and Q2 also used for imput triggering and output signal inhibition to provide the RPM limiting function.

Abstract: The present invention is an ignition control system for an engine having at least one combustion chamber and an ignition element for initiating combustion in the chamber. As one aspect of the ignition control, a switching circuit is provided for controlling the firing of the ignition element based upon either a signal received from a mechanism which detects and outputs a first firing timing signal or a computing mechanism which outputs a second firing timing signal based upon the first firing timing signal. As a second aspect of the ignition control, ignition elements are paired and fired together. In this arrangement, the ignition control includes a mechanism for counting outputted firing signals and assigning them values. These values are used to control the firing of the pairs of ignition elements, permitting the pairs of elements to be fired such that combustion initiation in individual combustion chambers corresponding is controllable.

Abstract: An internal combustion engine assembly including an internal combustion engine including an engine block having at lest one cylinder, a piston mounted within the cylinder for reciprocal movement in the cylinder, a fuel injector for injecting fuel into the cylinder, the fuel injector initiating a fuel injection event at a predetermined time and a circuit for generating a spark in the cylinder a predetermined amount of time after the injection event to cause combustion of fuel in the cylinder.

Abstract: An engine speed limiter for an internal combustion engine having an ignition primary winding that outputs an ignition pulse and fires a spark plug in response to the ignition pulse is disclosed. An electrical storage device receives electrical energy from the ignition primary winding. A control circuit receives electrical energy from the electrical storage device and generates a trigger signal. The potential of the received electrical energy of the controller is limited to a predetermined value by the controller. A switching mechanism is responsive to the trigger signal and shorts the ignition pulse, thereby preventing the spark plug from firing.

Abstract: An engine control for an engine powering a watercraft is disclosed. The engine has a body defining at least two combustion chambers. An air supply system supplies air to the combustion chambers, the air supply system including a throttle control for controlling the flow rate of air to the engine, the throttle control moveable between an open and a closed position. A fuel supply system supplies fuel to the combustion chambers. At least one ignition element ignites the air and fuel supplied to the combustion chambers. At least one exhaust passage leads from the combustion chamber to a point exterior to the body through which exhaust may pass. Exhaust control means are provided for controlling the timing of the flow of exhaust through the passage.

Abstract: An engine speed command selector and method of selecting an engine speed command signal from two command signals includes a selector switch having a local and a remote position, a local low indicator, a local high indicator, a local mode indicator and a remote mode indicator; the engine speed command selector permits an operator to change between local and remote mode when a local engine speed command is within a predetermined tolerance of a remote engine speed command and the operator has moved the selector switch to the desired mode position.

Abstract: An engine speed restriction system for an internal combustion engine having at least two combustion chambers, an ignition system including an ignition element corresponding to said combustion chamber, and an engine speed sensor is disclosed.

Abstract: A selective call module (102), installed in a land vehicle having an engine with an ignition system (118), has a selective call receiver (104), a microprocessor (106) and a non-volatile memory (108). The selective call module is connected to an engine control module (116) of the land vehicle. The microprocessor decodes received selective call signals and causes the selective call module to enter into a shutdown state upon decoding of a shutdown page. In the shutdown state, the selective call module measures the engine speed and immediately shuts down the engine by completely turning off the ignition system if the engine speed is less than a pre-set value. The selective call module gradually shuts down the engine by interrupting the ignition system for gradually increasing durations if the engine speed is greater than the pre-set value.

Abstract: An internal combustion engine having at least one variable volume combustion chamber with an intake passage leading thereto, an ignition element for igniting an air/fuel mixture in the chamber, an exhaust passage leading therefrom and including a catalyst in communication therewith, and an emission control for controlling the emission content is disclosed. Preferably, the emission control comprises a mechanism for closing the intake passage leading to the chamber in the event an engine abnormality is detected and an engine ignition misfire mode is employed, thereby preventing the emission of unburned air and fuel into the exhaust passage leading to the catalyst.

Abstract: Cyclic variation in combustion of a lean burning engine is reduced by detecting an engine combustion event output such as torsional acceleration in a cylinder (i) at a combustion event (k), using the detected acceleration to predict a target acceleration for the cylinder at the next combustion event (k+1), modifying the target output by a correction term that is inversely proportional to the average phase of the combustion event output of cylinder (i) and calculating a control output such as fuel pulse width or spark timing necessary to achieve the target acceleration for cylinder (i) at combustion event (k+1) based on anti-correlation with the detected acceleration and spill-over effects from fueling.

Abstract: A programmable interface which connects to an engine control device and allows convenient entry of engine performance limitation data such as maximum allowable vehicle speed and engine RPM's. Such entered data is stored and processed so as to interface with existing and/or modified engine controllers to produce the desired vehicle performance limitations. Programmable data entry devices include an alphanumeric keypad, a wireless remote keypad, a keychain unit, and an encoded ignition key. Wireless transfer of data can be achieved through RF or light transmitters/receivers, or active and passive transponders/interrogators. Once processed, the data can be used, for instance, to alter or generate pulse trains which control ignition spark, fuel injection, or carburetion.

Abstract: A speed limiting circuit measures the speed of the engine through the use of a device that functions generally as a tachometer. A speed signal is provided and is a function of the frequency of a plurality of pulses provided by a pulse generator. The frequency of the plurality of signal pulses, in a preferred embodiment, is representative of the frequency of a plurality of voltage pulses provided by an ignition coil. Since the voltage pulses from the ignition coil are directly related to the speed of the engine, the speed signal from an integrator can be used as an accurate representation of the engine speed. This speed signal can then be differentiated to determine the acceleration of the engine. The speed signal and acceleration signal are combined by an adder and the combined signal that results is compared to a threshold magnitude.

Abstract: A programmable interface which connects to an engine control device and allows convenient entry of engine performance limitation data such as maximum allowable vehicle speed and engine RPM's. Such entered data is stored and processed so as to interface with existing and/or modified engine controllers to produce the desired vehicle performance limitations. Programmable data entry devices include an alphanumeric keypad, a wireless remote keypad, a keychain unit, and an encoded ignition key. Wireless transfer of data can be achieved through RF or light transmitters/receivers, or active and passive transponders/interrogators. Once processed, the data can be used, for instance, to alter or generate pulse trains which control ignition spark, fuel injection, or carburetion.

Abstract: A discharge ignition apparatus for use with a small internal combustion engine has built-in overspeed disable capability. At operating speeds below an overspeed threshold, revolution of a magnet assembly past a stator unit having a magnetically permeable core causes accumulation of charge across a storage capacitor. When the capacitor has reached a fully charged state, a triggering signal is applied to the gate of a SCR device to cause rapid discharge through the primary coil of a step-up transformer. The higher voltage produced at the secondary coil of the step-up transformer is then applied across the gap of a spark plug. At operating speeds exceeding the overspeed threshold, a second trigger circuit renders the SCR conductive prior to substantial accumulation of charge across the storage capacitor. The second trigger circuit includes a zener diode or other voltage threshold element in circuit with a trigger coil operative to produce a speed dependent voltage signal.

Abstract: A marine propulsion system and particularly an outboard motor wherein the outboard motor is provided with a control for preventing engine damage in response to an abnormal condition by reducing the speed of the engine through disabling certain cylinders. The cylinders disabled are chosen on the vertical position of the cylinder in the engine so as to provide improved running and avoid undesirable results. In addition, the disabling of the cylinders is precluded until the abnormal condition has existed more than a predetermined time period upon initial start-up so as to permit unencumbered normal warm up of the engine.

Abstract: A procedure to control the drive unit in motor vehicles wherein: the maximum engine performance characteristic is determined; as a minimum engine performance characteristic, a reference performance characteristic is specified by how drive resistance depends on vehicle speed at a medium payload of the motor vehicle; above the reference performance characteristic, a first performance characteristic which is dependent on actual driving speed is defined and allocated a minimum assessment value; between this first performance characteristic and the maximum engine performance characteristic, a second performance characteristic which is also dependent on actual driving speed is defined and allocated a maximum assessment value; the current engine performance is determined; current assessment values are determined by comparing current engine performance to the first performance characteristic and the second performance characteristic; the current assessment values, as continuously determined, are filtered over time in

Abstract: A system for providing an indicator light operated by a fluid level sensor, including a power source providing the voltage to a first node, a first LED and a first circuit branch connecting the first node to ground, a voltage dropping component in the first circuit branch, a second circuit branch including a second LED connected to the first node in parallel with the first LED, and a normally open first fluid level switch that can close to connect the second circuit branch to ground. The sum of the turn on voltage of the first LED and the voltage drop across the voltage dropping component when the first LED is on is greater than the voltage drop from the first node to ground through the second LED when the first switch is closed, so that the first LED is normally on when the first switch is open, and the second LED is on and the first LED is off when the first switch is closed.

Abstract: An electronic ignition system replacing corresponding stock circuitry but utilizing the stock magneto and ignition coil provided with the engine of a sport vehicle, such as a jet ski or snowmobile, to provide improved performance. A timing circuit is provided as part of the ignition circuitry to enable a trigger pulse of a predetermined duration to be delivered to the ignition coil and further, to inhibit subsequent trigger pulses limiting the engine speed below a determined rpm limit. The timing circuitry uses an over-temperature switch connecting a capacitance to lengthen the inhibit time period reducing the maximum rpm limit. A holeshot switch connected across the over-temperature switch lowers the rpm limit while the throttle is held in the full speed position. Compensated pickup circuitry, automatic battery connect/disconnect, low impedance kill switch circuitry and an impedance protected tachometer output is provided to enhance the performance and features of the ignition systems of sport vehicles.

Abstract: A variable integration based ignition circuit for an internal combustion engine recognizes predetermined engine conditions and modifies or limits ignition advance when the predetermined conditions are violated to protect the engine. The ignition circuit includes an ignition triggering circuit which causes the engine ignition to ignite in response to ignition pulse signals. A pulse generator generates and outputs signal pulses when the sensor detects positions of the crankshaft. A speed detector calculates the rotational speed of the flywheel based on the signal pulses. Ignition pulse signals are retarded when the rotational speed exceeds a predetermined level to limit rotational speed and protect the engine. The ignition circuit may also limit ignition pulse signals in response to low oil pressure.

Abstract: An apparatus for identifying the power stroke of a particular cylinder in a multi-cylinder engine which utilizes a wasted spark electronic distributorless ignition system but lacks a camshaft driven cylinder identification sensor, wherein a single sensor can be placed in a coil pack adjacent to and substantially equidistant from the ignition coil towers. The sensor will produce a signal reflecting the difference in voltage drops between corresponding pairs of spark plugs who share the same coil and which utilizes this signal to determine the power stroke of individual cylinders to produce a resulting synthetic cylinder identification signal. This apparatus can further be used as a permanent on-board sensor, thereby negating the need for a separate camshaft driven sensor, to determine the cylinder identification.

Abstract: The invention is directed to an ignition circuit for an internal combustion engine in a portable handheld work apparatus wherein a work tool is driven via a clutch. The ignition circuit includes an ignition time point control which connects a spark plug via a switch to a voltage source in order to trigger an ignition spark. The spark plug is mounted in the combustion chamber of the engine. This connection takes place in dependence upon the crankshaft angle and the rpm of the engine. In order to prevent damage to the clutch because of a blocked work tool, a test value counter driven via a rpm gate circuit is provided. The test value counter increments its value in the pregiven rpm window of the gate circuit with each rotation of the crankshaft and the content of the test value counter is compared to a pregiven limit value by a comparator. The output of the comparator activates a rpm-reducing protective circuit and the output of the comparator indicates reaching or exceeding the limit value.

Abstract: In a method and apparatus for limiting the speed of motor vehicles, in cases where a speed signal is not available, engine cut-off is not rigidly activated upon exceeding a constant rotational speed threshold. Rather, a variable rotational speed threshold is determined which takes into account instantaneous or previous driving states, thereby being responsive to instantaneous or previous reactions of the vehicle's driver. This provides for an intelligent engine cut-off which accounts for operating conditions and, thus, can substantially better respond during critical driving situations.

Abstract: When the output from an internal combustion engine is reduced using a combination of a throttle valve control device, a fuel cut control device and an ignition retard control device, the starting point of operation of the ignition retard control device in a control region of condition for an excessive slipping of the driving wheel is provided between the starting region of operation of the throttle valve control device and the starting region of operation of the fuel cut control device. This permits the fuel cut control device to have a high responsiveness to a sudden variation in excessive slipping and no exhaust heat to be discharged, and also permits the throttle valve control device to become lower in responsiveness after the excessive slipping has been substantially converged but to have a small variation in fuel-air ratio. The ignition retard control device starts operation only when the excessive slipping cannot be suppressed by the throttle valve control device.

Abstract: A capacitor discharge engine ignition system that includes a charge coil responsive to a flywheel magnet for charging an ignition capacitor, and a trigger coil responsive to the flywheel magnet for triggering an SCR rapidly to discharge the capacitor through the primary of the ignition coil. Circuitry for automatically electronically limiting overspeed operation of the engine includes a capacitor connected to the trigger coil, and a voltage divider connected between the capacitor and the gate of the SCR. This capacitor is charged upon occurrence of each trigger signal, and during normal operation has sufficient time to discharge through the voltage divider before generation of the charge signal. However, when the engine is operating at excessive speed, there is sufficient charge on the trigger capacitor to gate operation of the SCR, short circuiting the ignition charge capacitor and preventing operation of the ignition.

Abstract: An electronic governor is disclosed for power producing and power absorbing devices having a minimum number of component parts. Power for all of the electronic governor components is supplied by a small coil, thereby avoiding the need for an additional coil frame or other power source. In a preferred embodiment, power supply circuitry converts the alternating signal from the coil to a direct current signal to power the governor. A signal conditioner also provides a low state signal to a 555 timer to start the timing cycle. The length of the timing cycle, and thus the high state control signal output of the timer, is a function of the desired device speed. When the timer output is at a high state while at the same time the alternating signal from the coil is at its first polarity, one or more switches conduct to adjust an electromagnetic actuator. In one embodiment, the switches control a motor connected to an engine throttle and operated in a stepper mode.

Abstract: An engine ignition controller in which, when a transmission is set at the first speed stage, ignition timing is set on the basis of an angle advance characteristic for causing the output of an engine to be decreased. Immediately before a vehicle speed reaches a vehicle speed limit, ignition is carried out according to an ignition pattern having a misfire rate to cause an increase rate of the vehicle speed to be decreased; while, when the vehicle speed exceeds the vehicle speed limit, ignition is carried out according to an ignition pattern having a misfire rate to cause the vehicle speed to be reduced. Further, different speed limits are set for respective speed stages higher in speed stage number than a certain speed stage so that, when the vehicle speed exceeds the vehicle speed limits, ignition is carried out according to ignition patterns to cause the vehicle speed to be decreased.

Abstract: The microprocessor-based speed limiter compares a speed value functionally related to the actual speed of the engine with a stored reference value and generates a limit signal to ground the ignition pulses if the speed value is greater than or equal to the reference value. The ignition pulses are preferably grounded for a preselected number of engine revolutions, after which another comparison is made to determine whether the actual engine speed is below the maximum limit speed. Both the stored reference value and the preselected number of engine revolutions may be changed.

Abstract: An ignition method and system for internal combustion engines, especially in lawn mowers or chain saws, in which a magneto induces a plurality of alternating voltage half-waves for each engine revolution to charge an energy-storing element and to discharge it by a switch controlled by the primary coil of an ignition transformer. The switch is actuated when the first half-wave of each revolution reaches a trigger threshold. The ignition system induces the charging alternating voltage dependent upon the rotary position of the engine for the energy storage element and for discharging it via the switch for firing the spark synchronously with the alternating voltage. The system has a timer module which responds to the alternating voltage by producing a signal to block the ignition switch for the duration of a time interval which corresponds to a top speed limit of the internal combustion engine.

Abstract: A governor apparatus for an internal combustion engine of a capacitor discharge type capable of effectively preventing after-burning due to excessive fuel supply and building abnormal combustion, etc., during the high-speed operation of the engine. To this end, ignition is intermittently performed or periodically stopped and performed when the number of revolutions per minute of the engine is greater than a predetermined value.

Abstract: An overrun preventing device is disclosed which selectively causes misfires to occur in one, two or three cylinders of a six cylinder internal combustion engine based on the detected engine speed. This overrun preventing device operates to prevent the ignition plugs from getting wet with fuel so that after a misfire has occurred in one or more of the cylinders, those cylinders can be easily reignited if desired.

Abstract: A method and an apparatus for driving an auxiliary device of an internal combustion engine according to the present invention is directed to preventing an over revolution of an engine by detecting a speed of the revolution of the engine, regardless the magnitude of an induced voltage of a primary winding of an ignition device.

Abstract: A speed governor for a vehicle with an internal combustion engine senses an engine operating condition indicating the vehicle speed. When the vehicle speed indicated by the operating condition exceeds a prescribed speed, the cylinders of the engine are temporarily prevented from firing for short periods until the vehicle speed falls below the prescribed speed. In one form of the invention, a first sensor that senses a first operating condition is used to determine the vehicle speed under normal operating conditions. When the first sensor becomes inappropriate or malfunctions, a second sensor that senses another operating condition is used to determine the vehicle speed.

Abstract: A method of and apparatus for enabling at least one spark plug of a internal combustion engine to provide a fuel igniting spark at a selectable time in the engine cycle is disclosed. Sensors provide a first engine rotation determined pulse train the repetition rate of which is the same as the number of revolutions per second of the engine and a second engine rotation determined pulse train the repetition rate of which is an integral multiple of that of the first pulse train. The reference pulse initiates a count of pulses in the second pulse train and, upon reaching a preselected count, initiates a count of pulses in a third independent pulse train having a much greater repetition rate. The spark plug is enabled when the third pulse train count reaches a preselected count.

Abstract: An engine protection system and protocol is implemented within an electronic engine control module. Various engine fluid parameters, such as coolant level and temperature, oil pressure and temperature, and air intake manifold temperature, are monitored and compared to limit values to determine if a fluid fault condition exists as to one or more of the fluid parameters. The engine performance is derated as a function of the severity of the fluid parameter fault. Two levels of faults are sensed to activate one of two derating schedules. In one schedule, the engine power, or torque as a function of engine speed, is gradually reduced or derated as the fluid parameter moves farther out of normal operating range. With this derate schedule, the engine will still run and the driver can still operate the vehicle, albeit at lower power levels than a healthy engine.

Abstract: An ignition method and system for internal combustion engines, especially in lawn mowers or chain saws, in which a magneto induces a plurality of alternating voltage half-waves for each engine revolution to charge an energy-storing element and to discharge it by a switch controlled by the primary coil of an ignition transformer. The switch is actuated when the first half-wave of each revolution reaches a trigger threshold. The ignition system induces the charging alternating voltage dependent upon the rotary position of the engine for the energy storage element and for discharging it via the switch for firing the spark synchronously with the alternating voltage. The system has a timer module which responds to the alternating voltage by producing a signal to block the ignition switch for the duration of a time interval which corresponds to a top speed limit of the internal combustion engine.

Abstract: A fuel supplying device for a marine propulsion unit wherein the engine is slowed in response to an abnormal condition by interrupting the ignition. In order to prevent excess fuel consumption and preclude backfiring, the fuel supply is also discontinued when the ignition system is interrupted.

Abstract: An engine control apparatus comprises a revolution speed sensor for detecting the number of revolutions of an internal combustion engine, an abnormality detecting means for detecting abnormality in the engine, and a control means for increasing or decreasing the number of misfire cylinders so that the revolution speed of the engine is brought down by a limited degree corresponding to a degree of abnormality of the engine when the abnormality is detected.

Abstract: Disclsoed is a system of protecting an engine of the type where a driving power is transmitted through a variable reduction gear ratio belt, in which when breaking of the belt is detected, control of stopping the engine is performed, or control of excessively enriching the air-fuel ratio of an air-fuel mixture supplied to the engine is performed and then, control of stopping the engine is performed.

Abstract: An apparatus and method for altering the acoustic signature of an internal combustion engine is disclosed. Several techniques for altering the acoustic signature of an engine are shown, including time-varying, disabling or cutout of individual cylinders of an engine in a random fashion in order to reduce the periodic characteristics of the exhaust noise of the engine. Alternate embodiments include offsetting crank pins to transform an even firing engine into an uneven firing engine, inhibiting the fueling of individual cylinders, and inhibiting the ignition signals provided to individual cylinders. A combination of the above techniques may also be implemented in order to disperse the exhaust noise energy present over a wide frequency range, making acoustic detection of the exhaust signature difficult. Cylinder cutout schemes are implemented over a single or multiple engine cycle to disperse exhaust noise pulses over time and randomize measurable spectral noise composition.

Abstract: A control system for an internal combustion engine, the control system receiving an input signal from an engine speed sensor, receiving an input signal from an engine knock sensor, advancing the spark timing of the internal combustion engine until a knock signal is received from the knock sensor, and, in response to receipt of a knock signal from the knock sensor, retarding the spark timing of the internal combustion engine until a knock signal is no longer received from the knock sensor and thereafter maintaining a substantially constant spark timing until the signal received from the engine speed sensor indicates a change in engine speed.

Abstract: This disclosure relates to apparatus for operating a combustion engine by controlling the spark ignition voltage to said engine. Said control is created by the application of two opposing currents to the input of an amplifying device which is used to selectively shunt a constant current source away from the control electrode of a second amplifying device connected to control the formation of said ignition voltage.