Abstract: A working apparatus has an internal combustion engine which drives at least one tool via a clutch. The clutch starts the coupling process at an initial engagement speed when the internal combustion engine is accelerated. The internal combustion engine has a piston, an ignition device and an ignition timing control device. The control device provides a first ignition timing for idling and a second ignition timing for full load operation, which is earlier than the first ignition timing. A method for operating the working apparatus provides that the ignition timing is adjusted toward “late,” with respect to the first ignition timing, when the engine speed drops in a first speed range above the idling speed and below the initial engagement speed.

Abstract: A method for controlling a vehicle engine having a plurality of cylinders is provided. The method comprises: during engine idling, advancing spark timing of at least one cylinder to before a peak torque timing, and retarding spark timing from the advanced timing toward the peak torque timing in response to decreased engine speed to maintain idling speed.

Abstract: An engine control system for use in connection with vehicles and the like allows the engine speed to be modified using the torque load from the electrical generator. The engine is subject to a torque load from a generator coupled to the engine. The controller compares the desired speed to the actual speed of the engine to determine an error value, and the torque load of the generator is modified (increased/decreased) based on the error value such that the absolute value of the error value is reduced. The generator control is combined with and arbitrated with respect to traditional spark control methods, thus reducing the need for spark timing that is substantially retarded from the mean best timing (MBT) setting. The electrical generator can operate in either voltage control mode or field duty cycle control mode, depending upon various conditions.

Abstract: A system and method for stopping an internal combustion engine. According to one aspect of the disclosure, a shutdown sequence of the engine includes retarding ignition timing relative to ignition timing prior to initiation of the shutdown sequence, and then advancing ignition timing relative to ignition timing prior to initiation of the shutdown sequence.

Abstract: The invention relates to a system for regulating an internal cumbustion engine (1). Said system regulates the maximum combustion pressure by modifying the start of the injection process. The aim of the invention is to improve the operational reliability of the internal combustion engine (1). To this end, the invention provides that the maximum combustion pressure (pMAX(i)) is diagnosed by the detection of a freak value. This then determines a first or second mode and sets a diagnosis value depending on the modi. The invention also provides that the output of the injection start regulator is limited by a limiting mechanism.

Abstract: A method and an arrangement control the drive unit of a vehicle. In this method and arrangement, an rpm limiting to a reference rpm takes place when the demand of the driver is withdrawn. The reference rpm is determined at the start of the withdrawal of the driver command.

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 warm-up control apparatus of an internal combustion engine is installed in a vehicle equipped with a brake booster that uses a negative pressure in an intake pipe of the internal combustion engine. The apparatus performs a warm-up control of the engine by retarding the ignition timing and increasing the amount of intake air. If during execution of the warm-up control, the brake pedal is operated, or the accelerator is off while the vehicle is running at or above a predetermined speed, or the decreasing rate of the amount of accelerator operation is greater than or equal to a predetermined value while the vehicle is running at or above a predetermined speed, the control apparatus recovers the intake pipe negative pressure by reducing the amount of intake air set in relation to the warm-up control.

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: Computerized system and method for controlling an internal combustion engine are provided. The system includes a speed-setting device operable to supply a signal indicative of a desired engine speed. A speed sensor is coupled to the engine to supply a signal indicative of the actual speed of the engine. An electronic control unit is coupled to receive the respective signals indicative of desired engine speed and actual engine speed. The control unit in turn includes a comparator configured to compare the respective signals indicative of desired and actual engine speed relative to one another and supply a comparator output signal based on the magnitude of any differences therebetween. A processor is responsive to the comparator output signal to adjust one or more engine operational parameters of the engine.

Abstract: A method and an arrangement control the drive unit of a vehicle. In this method and arrangement, an rpm limiting to a reference rpm takes place when the demand of the driver is withdrawn. The reference rpm is determined at the start of the withdrawal of the driver command.

Abstract: A control apparatus controls the rotational speed of an internal combustion engine by generating a command value for ignition timing of the internal combustion engine to convert an actual rotational speed of the internal combustion engine to a predetermined target rotational speed according to a feedback control process and controlling the ignition timing based on the generated command value. The feedback control process is carried out by a response designating control process capable of variably designating a rate of reduction of the difference between the actual rotational speed of the internal combustion engine and the target rotational speed with the value of a predetermined parameter in the feedback control process. The value of the predetermined parameter is variably established under a predetermined condition.

Abstract: Undershoot of rotation speed is prevented by increasing an intake air amount of an engine when it decelerates. Precise control corresponding to differences of a deceleration state is realized by setting an increase amount of intake air to a different value according to the engine rotation speed and deceleration. Preferably, increasing of intake air amount starts when the engine rotation speed reaches a first predetermined value. It is terminated when the engine rotation speed reaches a second predetermined value smaller than the first predetermined value or when a predetermined time has elapsed, whichever is the sooner.

Abstract: Control arrangements for the induction system of an internal combustion engine having a control valve in the induction passage which is moveable between an opened position wherein the flow into the combustion chamber is unrestricted and in a first direction and in closed position wherein the flow into the combustion chamber is restricted to accelerate the velocity of the charge entering the combustion chamber and change its direction from the first direction. Optimum positions are set for the control valve in response to engine speed and engine load but the control valve is held in a closed position when the engine speed is below a predetermined speed and regardless of the load and is also held in an opened position when the engine speed is above a second predetermined speed and regardless of load. Various routines are shown for positioning the control valve to accommodate catalytic convertor warm up, sudden acceleration or deceleration conditions and other transient conditions.

Abstract: The invention is a further development of an earlier arrangement of r.p.m. limitation (SE-P-452 355). The advantage of this invention is that the adjustment of pulse times is eliminated. The arrangement can be manufactured without cost demanding adjustment as the circuit is crystal-controlled which involves a great accuracy. As the r.p.m. increases, the pulse t.sub.2 of the second flip-flop comes closer to the next ignition pulse of the ignition system and, at the limitation speed, t.sub.2 begins to overlap the ignition pulse. The ignition time T is delayed and an ignition delay takes place with a subsequent limitation of the r.p.m.

Abstract: A system controlling the spark timing for an internal combustion engine having ignition plugs, a fuel supply control system for cutting off the fuel supply to the engine including a fuel supply cutoff delay means is disclosed.According to the present invention, there is provided a system for controlling the spark timing comprising a means for retarding the spark timing from an optimum spark timing whose value is derived on a basis of the engine speed or engine speed and air flow rate per rotation, whereby the shock generated due to abrupt changes in engine torque when the fuel supply cutoff delay means is operated are reduced.

Abstract: An internal combustion engine and method of operating it that improves combustion efficiency, fuel economy and exhaust emission during low speed running. The engine is equipped with a relatively conventional main induction system and an auxiliary induction system having a substantially smaller cross sectional area for delivering a charge to the chambers of the engine at a high velocity to improve turbulence and combustion efficiency. A control valve arrangement is incorporated so that the idle and low speed requirements are supplied through the auxiliary induction system and the medium and higher load charge requirements are supplied primarily through the main induction system. An exhaust gas recirculating system is incorporated for reintroducing exhaust gases to the combustion chamber so as to reduce the emissions of nitrous oxide.

Abstract: A device for controlling an electromechanical transducer such as a proportional electromagnetic valve, in which a pulse signal having a constant period shorter sufficiently than the minimum response time required for the displacement of the plunger of the proportional electromagnetic valve over its predetermined full stroke is applied to the electromagnetic coil of the proportional electromagnetic valve to superpose a very small vibratory stroke component on the stroke of the plunger, and the duty cycle of the pulse signal applied to the electromagnetic coil is varied so as to urge the plunger in directly proportional relation to the variation of the duty cycle without substantially giving rise to mechanical hysteresis in the stroke of the plunger.

Abstract: A throttle positioning system is provided for holding a throttle valve at a position slightly more open than at the normal idling position, and an idle vacuum advance mechanism is provided for advancing the ignition timing when the throttle valve is at a position less than a predetermined opening degree. The idle vacuum advance mechanism is disabled from advancing the ignition timing when the throttle positioning system is operating.

Abstract: A fail safe device for isolating the revolution limiter from the ignition system of an internal combustion engine, in which the output stage of the revolution limiter is continuously monitored to ascertain whether or not it is absorbing ignition pulses at a speed lower than the limiting speed. In the event that the absorption of ignition pulses is taking place at a speed lower than the limiting speed, the fail safe device becomes operative upon the engine revolutions falling below a given value and causes a fuse in series with the output stage of the revolution limiter to blow, thus isolating the revolution limiter from the ignition system to allow ignition to be instantly re-established in the event of a fault occuring in the revolution limiter.

Abstract: In an internal combustion engine in which the fuel supply is interrupted during no-load operation to save gas the ignition timing is retarded following resumption of the fuel supply to cause the resumed torque to be applied slowly. A sequence of ignition timing signals following the activation of the gas pedal is delayed by sequentially smaller and smaller amounts until the normal ignition timing is resumed.

Abstract: An ignition system for an internal combustion engine, which includes circuitry for producing pulses at a frequency directly related to rotational speed of the engine and a capacitor discharge circuit. A first monostable circuit responsive to the pulses is arranged for triggering the capacitor discharge circuit by passing from its stable state to its unstable state. A second monostable circuit responsive to the pulses is arranged for triggering the capacitor discharge circuit when passing from its unstable state to its stable state. The time constant of the first monostable circuit is substantially equal to the frequency of the ignition system discharge corresponding to the maximum admissible speed of the engine. The time constant of the second monostable circuit being equal to a predetermined value equal to a value of retarded ignition allowing operation of the engine at a reduced power.

Abstract: A vehicle engine includes throttle stop control apparatus including means effective to store a plurality of induction passage pressure numbers corresponding to specified values of engine speed. Further apparatus measures engine speed and induction passage pressure and compares the induction passage pressure with a control reference number derived from the induction passage pressure reference number corresponding to the measured engine speed. When the throttle is in the idle position and the induction passage pressure signal exceeds the reference, a throttle stop control loop is closed on engine speed to maintain a predetermined engine idle speed. However, when the throttle is in the idle position and the induction passage pressure signal does not exceed the reference, the throttle stop control loop is closed on induction passage pressure to maintain substantially the reference pressure, whereby throttle position during vehicle coastdown is controlled according to a predetermined stored schedule.