Abstract: Provided is an internal combustion engine ignition device capable of preventing an output signal level of a drive circuit from changing sharply when shifting from a normal ignition operation mode to a protection operation mode while reducing the cost of dedicated components and the like. An internal combustion engine ignition device of the present invention includes a first differential circuit for outputting a drive signal in a first mode and a second differential circuit for outputting a drive signal in a second mode, where the first differential circuit and the second differential circuit each include a transistor and are configured such that a drive current for supplying the drive signal flows through the transistor which is common between the first mode and the second mode.

Abstract: A method assesses the rotational speed of a machine, and more particularly the rotational speed of a rotating equipment prime mover controlled by a governor. Such machines include turbo machinery and relate to a measurement device for measuring speed. The method measures a number of pulses during a measurement interval, determines a portion of a pulse pattern, determines an integration period, and calculates the rotational speed based on the portion of the pulse pattern.

Abstract: To satisfy both a request for ensuring worker's safety at the engine start and a worker's request for promptly starting a work, on the premise of a working machine including an engine RPM suppression mode. A working machine (1) has a centrifugal clutch (6). The engine RPM suppression mode is executed at the start of an internal combustion engine (2). With the RPM suppression mode, the RPM of the internal combustion engine (2) is controlled not to exceed a clutch-in RPM. The working machine (1) has a mode cancelling means (S5) canceling the engine RPM suppression mode when a predetermined mode cancelation condition for cancelling the engine RPM suppression mode is satisfied, and a cancellation condition changing means (S2) changing the mode cancelation condition depending on a change in an engine operational state and/or an environment.

Abstract: Methods and apparatus are discloses for position a vehicle. In one aspect, an apparatus for positioning a vehicle is provided. The apparatus comprises a plurality of receive, each configured to generate a respective voltage signal from a wireless magnetic field generated by a field generator. The apparatus further comprises a processor configured to determine a first set of data based on the respective voltage signals generated by the plurality of receive coils, and reduce the first set of data to a second set of data that is substantially constant regardless of relative rotation between the plurality of receive coils and the field generator. The apparatus is further configured to determine a plurality of candidate positions based upon the second set of data, which are used to determine a position and an orientation with respect to the field generator based on the first set of data.

Abstract: A system and method for the automated remote management of an electronic control module wherein the settings, configuration, or operating parameters of an electronic or engine control module may be remotely retrieved, changed, or updated while the engine, vehicle, or transportation system is in operation to allow the change of settings to affect the manner, method, or speed of operation of the engine, vehicle, or transportation system during that operation based on external rules or criteria without the need for manual human input or direction.

Abstract: An internal combustion engine (1) may include a combustion chamber (41) into which a mixture (40) of fuel and air is supplied, a spark plug (50) disposed proximate to the combustion chamber (41) to ignite the mixture (40) by generating a spark such that ignition of the mixture drives a piston (6) operably coupled to a crank portion (12) of the engine (1), a speed sensor (102) configured to determine engine speed, and an electronic control unit (100) configured to control operation of the spark plug (50). The electronic control unit (100) may be configured to initiate a speed limitation operation in response to engine speed reaching a cut out speed threshold and to control ignition timing within an operating band (320) of ignition angles prior to engine speed reaching the cut out speed threshold. The speed limitation operation may include skipping application of sparks.

Abstract: A system and method for assessing the presence or absence of ignition coil degradation for an ignition system that includes two ignition coils for each spark plug. Ignition coil degradation may be determined without having to monitor ignition coils via specialized hardware circuitry. In one example, degradation of one or more ignition coils may be inferred from cylinder the presence or absence of cylinder misfire.

Abstract: A handheld work apparatus has a combustion engine which drives a tool of the work apparatus via a centrifugal clutch. The centrifugal clutch couples in an engagement rotational speed range (nK) which extends between a lower engagement rotational speed (nu) and an upper engagement rotational speed (no). The engine has a fuel supply device, an ignition device, a control device and a device for detecting the rotational speed (n) of the engine. A method for operating the handheld work apparatus makes provision for the rotational speed profile of the combustion engine to be monitored in the engagement rotational speed range (nK) and for the power (P) output for driving the tool to be increased from an operating power (P1) to an increased power (P2, P3) when the rotational speed profile corresponds with a predetermined rotational speed profile over a predetermined period of time (?t).

Abstract: An engine over speed detection circuit for determining an engine over speed condition is described. The circuit includes a detection unit configured to send a pulsed signal indicative of engine speed; a reactive impedance configured to discharge upon receipt of a pulse of the pulsed signal at a rate defined by the pulsed signal; a comparator unit to compare a voltage or current value of the reactive impedance with a threshold value and to output the result of the comparison at the rate of the pulsed signal.

Abstract: In an apparatus for detecting tip-over of a rammer equipped with a crankcase accommodating an output shaft rotatably connected to an engine, a movable unit accommodating a converter mechanism for converting rotation of the output shaft to vertical motion of a movable member, a tamping shoe connected to the movable unit, and a handle operable by an user, and adapted to thrust upward in the gravitational direction by the vertical motion of the movable member and go into a free fall to compact a ground surface, it is determined whether a detected engine speed becomes equal to or smaller than a threshold value set lower than an engine idling speed when the engine has been operated at a rammer working speed set greater than the engine idling speed, and if it does, it is discriminated that the rammer has tipped over.

Abstract: An engine includes a catalyst disposed inside an exhaust passage that guides exhaust discharged from a combustion chamber and a controller programmed to control a throttle valve and a fuel injector. If the engine is overheating, the controller is programmed to control the opening degree of the throttle valve or the injection amount of fuel from the fuel injector to decrease the rotational speed of the crankshaft and to control the injection amount of fuel from the fuel injector to set a target air-fuel ratio to a value richer than a stoichiometric air-fuel ratio.

Abstract: An engine ignition shutdown module includes a voltage regulator circuit connected to a key switch, and a pair of isolated MOSFET driver circuits connected to the voltage regulator circuit. Each MOSFET driver circuit charges a capacitor while the key switch is in a run position and the interlock switches are closed, and each capacitor discharges through a resistor for a time delay period once the key switch is moved from the run position to an off position or at least one of the interlock switches are opened. A pair of high voltage output MOSFET transistors are switched on while the capacitors discharge and provide an output to a magneto ignition for the time delay period.

Abstract: A method controls the rpm of a combustion engine in a hand-held work apparatus such as a brushcutter. The engine drives a work tool via a clutch which engages as a function of the engine rpm (n). A spark plug is arranged in the combustion chamber and is driven by an ignition unit. During start of the engine, an rpm lock circuit is active and defines a control variable as a function of the instantaneous rpm (nact) of the engine. According to the magnitude of this control variable, operating parameters of the engine are adapted to change the instantaneous rpm (nact). A control variable is determined for the adaptation of the operating parameters by the rpm lock circuit. The switch-off of the rpm lock circuit is provided when the control variable of the control lies outside a predetermined bandwidth of the absolute magnitude of the control variables.

Abstract: In an apparatus for controlling a boat equipped with an outboard motor mounted on its stern and having an internal combustion engine, a propeller to be driven by the engine and a propeller pitch changer adapted to variably change a pitch of the propeller, an opening of a throttle valve installed at an air intake system of the engine and its change amount are detected, and based on the change amount of the detected opening of the throttle valve, it is determined whether or not the pitch of the propeller is to be changed through the propeller pitch changer.

Abstract: A method controls the rotational speed limiting of an engine in a handheld work apparatus. The crankshaft of the engine drives a worktool via a clutch which engages in dependence on the motor rotational speed. Above an engaging speed of the clutch, a drive connection with the crankshaft is made and below the engaging speed, the drive connection is interrupted. A speed control unit monitors the rotational speed of the engine and includes a rotational speed lock circuit which limits the speed to a limit below the engaging speed. During the start of the engine, the lock circuit is switched on; it is switched off after the engine has been taken into operation when a deactivation signal is present, wherein the deactivation signal is generated when an operation change signal of the work apparatus is detected.

Abstract: The present invention provides a vehicle wheel spin control apparatus that, when it is determined that a wheel spin occurs, reduces engine torque to prevent the wheel spin, including: detecting driving control information and information on the state of a vehicle and determining whether basic conditions required to perform engine torque limit control to prevent the wheel spin are satisfied; when the basic conditions are satisfied, calculating a speed variation and the speed gradient value, and comparing the speed gradient value with a predetermined speed gradient value to determine whether a spin occurs; when it is determined that the spin occurs, using a torque gradient map set according to the current engine torque to perform the engine torque limit control; and when the vehicle speed is reduced by the engine torque limit control and cancellation conditions are satisfied, canceling the engine torque limit control and returning to normal control.

Abstract: An internal combustion engine (8) has an ignition device, a device for supplying fuel and a device for detecting the rpm of the engine (8). The engine (8) includes a permissible limit rpm (ng) and a control range (A) of the rpm (n) above the limit rpm (ng). A method for operating the engine (8) provides that the rpm of the engine (8) is limited in the control range (A) because of suppression of the ignition in individual engine cycles wherein the rpm (n) lies above a control rpm (na) lying in the control range (A). In the control range, and to improve the exhaust-gas values, the noncombustion engine cycle ratio (NECR) is adjusted. The NECR indicates the ratio of the number of engine cycles wherein the ignition is suppressed to the total number of ignitions.

Abstract: An electronic means for monitoring and controlling engine performance. The device takes input signals from vehicle engine speed sensor and ignition values. The electronic means is capable of recording an RPM event, and playing it back on the existing vehicle tachometer. Either the entire RPM event may be replayed, or the highest RPM value achieved during the event. Furthermore, the electronic means comprises a dial to set the RPM limit of an engine to prevent over-revving. Once the engine reaches the maximum user-defined RPM value, the electronic means interrupts the ignition system to prevent the engine from revving above such pre-determined value. The electronic means further comprises a shift light which illuminates once an engine reaches a pre-determined RPM value in order to alert the driver to shift gears.

Abstract: In one example, a method is described for operating an engine of a vehicle, the engine having a combustion chamber. The method may include controlling a stability of the vehicle in response to a vehicle acceleration; and adjusting dilution in the combustion chamber of the engine to reduce surge in response to the vehicle acceleration. The dilution may be adjusted by adjusting cam timing, for example.

Abstract: An engine control system comprises a coolant temperature weighting module that generates a weighting signal based on coolant temperature. A composite temperature generating module generates a composite temperature based on the coolant temperature, an oil temperature and the weighting signal. A delta friction torque module calculates delta friction torque of an engine based on the composite temperature. An engine operating parameter module that adjusts an engine operating parameter based on the delta friction torque.

Abstract: The present embodiments relate to a digital over speed circuit including a controller configured to calculate the speed of an engine and shut down the engine electronically when an over speed condition exists. The digital over speed circuit may be easily installed by the end user. Only a single wire is needed between the digital over speed circuit and the engine. Further, the digital over speed circuit does not require a reset or any user action of any kind after the over speed condition has been detected and power removed from the engine. In other words, there is no ON switch, and the user may immediately start the engine again after the engine has stopped and the digital over speed circuit has reset.

Abstract: A method of operating an engine having a plurality of cylinders, the method comprising of transitioning the engine from a first mode to a second mode, and temporarily adjusting an amount of torque produced by a cylinder of the engine for at least one cycle responsive to a difference in an amount of torque produced by a previous firing cylinder and a subsequent firing cylinder.

Abstract: The electric supercharger includes a vehicle connector, an impulse signal generator empowered by a power source, and a signal amplifier. The vehicle connector has a positive terminal and a negative terminal for electrically connecting to an electrical source of said vehicle. The impulse signal generator, which is electrically linked to the vehicle connector for receiving an impulse signal from the electrical source of the vehicle, includes a signal integral circuit stably generating a rectangular impulse signal. The signal amplifier electrically connects to the impulse signal generator to amplify the rectangular impulse signal and to send the amplified rectangular impulse signal back to sparkplugs and injectors of the vehicle through the vehicle connector for enhancing a combustion-efficiency of an engine of the vehicle.

Abstract: A controlled slow down apparatus and method for use in the event that a light-duty combustion engine has entered a state of excessive speeds or auto-ignition. The controlled slow down method is preferably initiated when the engine speed exceeds an activation speed for a predetermined number of engine revolutions. Once initiated, the controlled slow down method uses a combination of ignition timing and spark ratio manipulations in order to disrupt the auto-ignition conditions and slow down the engine in a controlled manner. Preferably, the controlled slow down method is only one part of an overall ignition control method, and can be incorporated within or utilized by one of a number of different ignition timing methods known in the art.

Abstract: A device that controls the engine speed of an internal combustion engine of a hand-held power tool has a protective control unit. The engine has an ignition control unit for controlling the ignition timing relative to a crank angle of a crankshaft based on the crankshaft speed and also has a centrifugal clutch driven by the crankshaft that begins to engage when a first engine speed is surpassed and is fully engaged when a second engine speed is reached. The protective control unit is activated within an engine speed range between the first and second engine speeds and monitors a dwell time of the actual engine speed within the engine speed range. When a predetermined dwell time of the actual engine speed is surpassed, the protective control unit intervenes in the combustion process and corrects the engine speed to a value that is outside of the engine speed range.

Abstract: An engine driven vehicle having a function of supplying power to an external load from a generator driven by an engine that is operated in a power generation mode while the vehicle is stopped, including: throttle position determination means for determining whether a throttle valve is placed closer to an acceleration side than a normal position in the power generation mode while the engine is operated in the power generation mode; and safety engine control means for conducting a control to prevent the engine from being operated at a higher speed than a set speed limit when the determination means determines that the throttle valve is placed closer to the acceleration side than the normal position in the power generation mode.

Abstract: A vehicle immobilization system (10) is coupled to a network system (20) and includes a vehicle that has a speed sensor (34) generating a vehicle speed signal, a telematics control unit (48) receiving and transmitting signals to and from the network (20), and a speed control module (72). An immobilization controller (30) is coupled to the speed sensor (34), the telematics control unit (48), and the speed control module (72). The immobilization controller (30) receives an immobilization signal from the network (20) and sets a maximum operating speed for the power train controller. When the vehicle speed signal is below the maximum operating speed, the immobilization controller reduces the maximum operating speed within the speed control module until a lower predetermined speed limit is met. The lower speed limit is preferably greater than zero so that some limited mobility of the vehicle may be achieved.

Abstract: A method and system for operating an engine wherein ignition of the engine is activated according to a predetermined timing schedule that references engine speed, and the ignition is suppressed above a predetermined engine speed threshold to allow engine speed to fall below the predetermined engine speed threshold. Thereafter, ignition is reactivated according to timing that is retarded relative to the predetermined timing schedule for a predetermined number of engine revolutions substantially when the engine speed has fallen below the predetermined engine speed threshold, thereby mitigating undesirable spikes in combustion chamber maximum pressure.

Abstract: The invention simplifies the structure of a magneto generator and stabilizes the operation of an internal combustion engine at the time of start-up, thereby providing an ignition device simplified in structure and reduced in size and providing improved safety to the internal combustion engine. In an ignition device for a capacitive discharge internal combustion engine, an ignition timing signal is calculated with a cycle detection signal obtained at a timing at which a forward voltage portion of an output voltage from a generator coil has reached a cycle detection voltage for making continual ignition operations available, and a peak voltage detection signal and a start-up voltage detection signal are obtained in accordance with a delayed reverse voltage portion of the output voltage from the generator coil. In a preset normal region speed or less in which a load is coupled to the engine, an ignition signal is output immediately after the peak voltage detection signal has been generated.

Abstract: An engine revolution limiter system is utilized to limit engine speed during a break-in period. The system provides for programming a variable break-in period and a variable selectable engine revolution limit. During the break-in period, if the revolution limit is exceeded by the engine speed, firing of the ignition is limited. In addition, the system provides for an over revolution limit wherein the ignition stops firing if the over revolution limit is exceeded. In addition, multiple break-in periods may be programmed with different associated revolution limits and over revolution limits. This provides for gradually increasing the allowable engine speed as the engine has been operating for greater periods of time.

Abstract: A method and arrangement for controlling the drive unit of a vehicle is suggested wherein a limiter is provided to limit the engine rpm to a pregiven limit value in at least one operating state. The limiter is controlled to be ineffective in this at least one operating state in dependence upon at least one additional operating variable.

Abstract: An engine controller for a vehicle having an automatic centrifugal clutch device, includes an engine halt controlling means (ECM) for performing engine halt control. The engine halt controlling means halts the engine with the condition that the engine speed becomes equal to or higher than a first set rotational frequency, which is set to be equal to or lower than the clutch engagement rotational frequency of the automatic centrifugal clutch device.

Abstract: A control system for general-purpose spark-ignition internal combustion engine to be used for a portable generator, etc., having one or two cylinders and an actuator connected to the throttle valve to open or close the throttle value. In the system, an adaptive controller with a parameter identification mechanism is provided which receives a detected engine speed and a desired engine speed as inputs, and computes a command value to be supplied to the actuator, using an adaptive parameter identified by the parameter identification mechanism, such that the detected engine speed is brought to the desired speed. In the system, the desired engine speed is determined such that the desired engine speed per unit time is not greater than a prescribed value and the command value is determined to be within the upper and lower limits of the throttle value.

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 monitoring the tachometer signal from the tachometer sensor and passing the tachometer signal to the ignition system if the engine speed is within predetermined limits. 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 vehicle speed and engine speed by disconnecting pulses from the tachometer sensor and generating time-delayed pulses of its own to delay the combustion of fuel until after the instance of maximum fuel compression, thereby reducing engine power when the vehicle or engine speeds exceed predetermined limits.

Abstract: The invention simplifies the structure of a magneto generator and stabilizes the operation of an internal combustion engine at the time of start-up, thereby providing an ignition device simplified in structure and reduced in size and providing improved safety to the internal combustion engine. In an ignition device for a capacitive discharge internal combustion engine, an ignition timing signal is calculated with a cycle detection signal obtained at a timing at which a forward voltage portion of an output voltage from a generator coil has reached a cycle detection voltage for making continual ignition operations available, and a peak voltage detection signal and a start-up voltage detection signal are obtained in accordance with a delayed reverse voltage portion of the output voltage from the generator coil. In a preset normal region speed or less in which a load is coupled to the engine, an ignition signal is output immediately after the peak voltage detection signal has been generated.

Abstract: The invention is directed to an ignition circuit for a two-stroke engine in a portable handheld work apparatus. A spark plug (2) is connected via a switch (14) to a voltage source (16). The ignition switch (14) is actuated by an electronic control circuit (15) which closes the ignition switch (14) in dependence upon the crankshaft angle and additional operating parameters such as the rpm of the engine (1) in order to trigger an ignition spark per revolution of the crankshaft (10). To limit rpm, the ignition switch (14) is held open when a pregiven end rpm is exceeded in order to suppress an ignition spark over at least one crankshaft revolution.

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 engine controller for a vehicle having an automatic centrifugal clutch device, includes an engine halt controlling means (ECM) for performing engine halt control. The engine halt controlling means halts the engine with the condition that the engine speed becomes equal to or higher than a first set rotational frequency, which is set to be equal to or lower than the clutch engagement rotational frequency of the automatic centrifugal clutch device.

Abstract: When a large load is exerted during restraint control of an engine of a jet propulsion boat, the drop of the engine revolution frequency causes a feeling of harsh braking. An engine revolution frequency control apparatus provided to prevent this problem includes a engine revolution frequency detector for detecting an engine revolution frequency, and threshold value setting units for setting first and second engine revolution frequency threshold values. The second threshold value is set to be higher than the first threshold value. An engine control unit includes an overspeed governing capability that starts restraint control for restraining rotation when the engine revolution frequency detected by the engine revolution frequency detector is more than said first threshold value when the engine is accelerating, and terminates restraint control when the engine revolution frequency is less than a second thresholds value during deceleration.

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: A method of controlling the engine speed of an internal combustion engine, the method providing the steps of determining the speed of the engine at a given time, determining the change in the speed of the engine from a previous determination of the engine speed, and using the values for engine speed and change in engine speed to determine whether a future event should be a combustion event or a non-combustion event.

Abstract: A method of controlling the speed of an engine whilst the engine is operating in a crank or idle state, including the steps of (a) determining when the engine is operating in said crank or idle state; (b) determining whether the engine speed is above an upper threshold speed, and (c) controlling the engine when the engine speed is above the upper threshold speed so as to effect a reduction in the engine speed to avoid an engine speed runaway event.

Abstract: A method and arrangement for controlling the drive unit of a vehicle is suggested wherein a limiter is provided to limit the engine rpm to a pregiven limit value in at least one operating state. The limiter is controlled to be ineffective in this at least one operating state in dependence upon at least one additional operating variable.

Abstract: When a large load is exerted during restraint control of an engine of a jet propulsion boat, the drop of the engine revolution frequency causes a feeling of harsh braking. An engine revolution frequency control apparatus provided to prevent this problem includes a engine revolution frequency detector for detecting an engine revolution frequency, and threshold value setting units for setting first and second engine revolution frequency threshold values. The second threshold value is set to be higher than the first threshold value. An engine control unit includes an overspeed governing capability that starts restraint control for restraining rotation when the engine revolution frequency detected by the engine revolution frequency detector is more than said first threshold value when the engine is accelerating, and terminates restraint control when the engine revolution frequency is less than a second thresholds value during deceleration.

Abstract: A capacitive discharge ignition system for an internal combustion engine including: a capacitor for storing electrical energy to produce a spark; a first switch having a trigger input for receiving a trigger pulse; a second switch connected to the trigger input of the first switch such that the trigger pulse may be selectively inhibited from triggering the first switch; and a speed sensor for detecting the speed of an engine and in communication with the second switch such that the second switch will not inhibit the trigger pulse when the speed of the engine is below a threshold speed and the second switch will inhibit the trigger pulse when the speed of the engine is above a threshold speed.

Abstract: A control system for general-purpose spark-ignition internal combustion engine to be used for a portable generator, etc., having one or two cylinders and an actuator connected to the throttle valve to open or close the throttle value. In the system, an adaptive controller with a parameter identification mechanism is provided which receives a detected engine speed and a desired engine speed as inputs, and computes a command value to be supplied to the actuator, using an adaptive parameter identified by the parameter identification mechanism, such that the detected engine speed is brought to the desired speed. In the system, the desired engine speed is determined such that the desired engine speed per unit time is not greater than a prescribed value. and the command value is determined to be within the upper and lower limits of the throttle value. In addition, the detected engine speed is smoothed and a gain for determining the convergence speed of the adaptive controller is determined appropriately.

Abstract: The invention relates to a generating unit driven by a combustion engine. Control of the engine speed is carried out in a known manner via a mechanical control device which controls a throttle valve in the carburetor system of the engine. In case of a failure of the mechanical control device and, consequently, in case of a change in the engine speed outside a predetermined range, an electronic control system takes over to activate a firing element of the engine and control the engine speed, independently from the mechanical control system, in such a way that the engine speed is maintained within the predetermined range.

Abstract: A device and a method determine an offset value which represents the offset of the output signal of a vehicle sensor, the sensor detecting at least one motion of a vehicle, and the output signal is analyzed at at least two different points in time. An additional signal is determined independently of the output signal, this signal also representing the motion of the vehicle. An arrangement is provided for analyzing the characteristic of the output signal, which depends on the longitudinal velocity of the vehicle, and the characteristic of the additional signal, which also depends on the longitudinal velocity of the vehicle, in order to determine the offset value.

Abstract: A revolution number control system includes ignition timing delay controlling means for delaying ignition timing from the ignition advance amount n at 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 present revolution number and the clutch-on revolution number n4 is the present 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: 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.