Showing papers on "Spark (mathematics) published in 1981"

Optimal closed-loop spark control of an automotive engine

Abstract: This work concerns the application of optimization theory to develop control laws for use in closed-loop control strategies to minimize the effect of environmental changes, manufacturing tolerances, and time degradation. The paper describes the acquisition of engine mapping data for 2.3L, 4 cylinder engine, the use of the data to develop analytical functions describing the fuel consumption and emissions, and the use of the functions in an optimization procedure to arrive at control strategies and driving cycle predictions of fuel consumption and emissions. The optimum schedules were used to determine a closed-loop spark control strategy.

Method and system for operation of a spark-ignited internal combustion engine

Abstract: A method and device for adjusting the timing of an internal combustion engine in response to knocking are provided. In the method, knocking signals are generated when the engine knocks and the timing is too far advanced. First correctional signals are generated in response to the knocking signals and adjust at one speed range one of several control curves. Second correctional signals are generated from the first correctional signals to adjust the control curves at the remaining speed ranges. The timing of the engine is retarded in response to the adjusted control curves until the knocking disappears. The system for adjusting the ignition timing comprises a knocking sensor, an ignition computer storing several control curves and generating ignition timing correction signals, a counter for generating signals to the ignition computer to change the control curves, a logic unit for receiving signals from the ignition computer and the knocking sensor and generating correction signals, and an interconnection device for adjusting the timing of the internal combustion engine in response to the ignition correction signals.

Electronic ignition input logic

Abstract: Information is derived from two given sets of sensor output pulses relating to crankshaft position for use in determining the proper cylinder to be fired, the spark time and the dwell. The spark is enabled only after the crankshaft position is known, and noise, including the spark itself, is prevented from interfering with the system operation.

Construction of a Compact Adjustable Waveform Spark Source

Abstract: An "open box" spark source is described. It is designed for easy adjustment of inductance and capacitance values while maintaining compact design to minimize radio frequency interference. The design allows monitoring of discharge parameters during operation, and can be assembled with minimal machining.

Spark timing system for spark ignition internal combustion engine

Abstract: A spark timing adjusting circuit receives a basic spark timing signal from a spark timing determining circuit and regulates the spark timing according to a knocking signal from a knocking detector. A speed changing circuit serves to increase the rate of advance of the spark timing after the spark timing has been retarded when the operational state of the engine is in a first predetermined range corresponding to a first speed range in which all the engine speeds are lower than a first predetermined value. The speed changing circuit may include a circuit which decreases the rate of retard of the spark timing when the operational state of the engine is in a second predetermined range corresponding to a second speed range in which all the engine speeds are higher than a second predetermined value which is higher than the first predetermined value, thereby avoiding rapid retardation of the spark timing. Alternatively, the first and second predetermined ranges of the operational state of the engine may be defined with respect to intake manifold vacuum, throttle valve opening or intake air amount to the engine.

A time-dependent theory of spark ignition

Abstract: A new theory of spark ignition has been formulated which includes for the first time the temporal dependence of the spark energy input. This theory is based on the observation made here that for ignition the spark kernel or hot bubble of gas created by the spark must grow to a critical size before its expansion velocity falls below a critical rate. A model of spark kernel growth has been developed which relates the time varying enery input to the kernel expansion in the high pressure region behind a spark induced strong shock wave or in an ambient pressure environment behind a weak shock. The strong shock kernel growth model was developed from a simulation of a time dependent energy release in an ideal gas without transport effects which was modified to reflect real gas behavior. The assumptions that energy losses from the spark kernel due to conduction, radiation or convection were negligible, were justified by existing experimental data and observations of spark ignition. Comparisons of observed spark kernel growth patterns and ignition energies with predictions made using this theory showed very good agreement for a wide range of pressures, air-fuel ratios and spark powers and durations for both stagnant and flowing gases. The increase in ignition energy and decrease in critical spark duration for flowing gases compared to stagnant mixtures were shown to be due to a distortion of the arc by the flow which makes some of the arc energy unavailable for ignition. The use of turbulent critical radii over-predicted the turbulent ignition energies, suggesting that even in turbulent flow the critical kernel size is the same as in laminar flow or stagnant cases.

Spark advance control mechanism for dual fuel engine

Abstract: Disclosed herein is a spark advance control mechanism for an engine capable of being selectively operated on gaseous fuel and on liquid fuel.

Breakdown in non uniform fields

Abstract: The paper presents a review of recent studies in the field of air breakdown. Coverage is given both to technological aspects of UHV systems and to the physics of spark breakdown, reflecting current interest in sparkover voltages, spark leader growth and space-charge effects

Spark timing control system

Abstract: A spark timing control system for an uneven firing engine utilizes a microprogrammed engine controller which produces a spark timing control system based on internal calculations using spark advance and dwell variables supplied by a microcomputer. A crankshaft position transducer produces a reference signal having alternate long and short pulses from which the firing cycle may be determined. The microcomputer is interrupted at each falling edge of the reference signal and based on a determination of the existing firing cycle, calculates and supplies appropriate spark advance and dwell numbers to the controller.

Calculation of Discharge Current Waveforms in High Voltage Spark Sources. I. Solution of Constant Parameter Model

Abstract: Equations are derived for computing the current waveform and instantaneous power dissipation in high voltage spark sources containing a branched waveshaping network. For constant or dual valued circuit parameters, examples of waveform characteristics are presented. Limitations of this constant parameter approach are discussed, and suggestions made for application of the equations for simulating nonlinear source and discharge behavior.

Knocking control system for use with spark ignition internal combustion engine

Abstract: A knocking control system includes a spark timing adjusting circuit which responds to the magnitude of knocking occurring in the engine to set an amount of retardation of the timing from a reference spark timing within a predetermined range. The spark timing adjusting circuit includes a range change circuit which responds to a drive signal produced from an engine operational state determining circuit, in order to change the predetermined range.

Spark ignition gas burner

Abstract: The invention relates primarily to a spark ignition gas burner for a cooker wherein the spark electrodes are so located as to avoid problems from contamination by spillage and of danger to the user. The invention makes use of alumina - a material hitherto unknown in such applications.

Gap control method for spark machining device

Abstract: PURPOSE:To control a working gap, by classifying spark waves according to the spark conditions and putting different wave in a servo circuit in accordance with the conditins. CONSTITUTION:Wave forms introduced from a pulse source 1 through a conductor (a) and wave forms introduced from an electrode 4 through another conductor (b) are compared by an interpole signal processing circuit 6 to classify the spark conditions into groups of effective discharge, no discharge, shortcircuit, arc discharge and other abnormal discharge. A different wave form is put in a servo circuit 2 in accordance with the classified discharge conditions. The servo circuit 2 averages the input to compare with a standard voltage, and its output actuates the electrode 4 through an electrode driving unit 3 and controls the working gap at a constant level.

Ignition spark timing circuit

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

Variable ignition distributor

Abstract: A variable ignition distributor for furnishing a high-voltage spark to a spark plug in a first cylinder and for furnishing a low-voltage spark to a spark plug in a second cylinder. A conventional distributor is modified so that a rotor of the distributor carries an ignition electrode for furnishing high voltage to the spark plug in the first cylinder and a variable electrode carried by the rotor furnishes low voltage to a spark plug in the second cylinder. The low voltage is generated at the same time as the high voltage so that there need be only one terminal connected to the ignition coil. Preferably, the variable electrode is adjustable so that the low voltage charge is furnished as a function of the operating speed of the engine.

Engine timed ignition system with improvement

Abstract: An engine timed ignition system of the type that combines a short duration high voltage spark with a reduced voltage DC spark sustaining signal. It includes in the system apparatus for starting the DC sustaining signal simultaneously with the high voltage spark. And, it includes apparatus to positively stop the DC sustaining signal after a predetermined interval in order to avoid a continuing spark discharge.

High action stabilizing system of compound spark chamber

Abstract: PURPOSE:To improve the stability of the chamber action by preventing the generation of the induction spark with instantaneous lowering of the field intensity by means of a high speed discharging circuit provided at the proportional chamber section of the compound spark chamber. CONSTITUTION:In the compound spark chamber 1 used as the radiation image detector such as beta ray camera, and beta ray released from the sample to be measured passes the electrode composing the proportional chamber 8, the working gas in the chamber 1 is ionized and the electrons produced are doubled in the high electric field between the electrodes 3 and 4 thereby generating lead spark between the electrodes 3 and 2. The high speed discharging circuit 19 provided with the hydrogen-filled thyratron 20 short in the ionization time, the triggering circuit 21 and the like are connected to the chamber 8. After the generation of the lead spark, the chamber 8 turns to a low electric field instantaneously by discharging until the induction spark starts to be generated. Thus, indication spark ceases. This prevents the generation of the false spark thereby highly stabilizing the chamber action.

Ignition time controller

Abstract: PURPOSE:To accurately predetermine the degree of spark advancement, by using two detectors, which generate reference position signals for the slow and rapid rotation of an internal combustion engine, to reduce the fluctuation in the degree of spark advancement and its lag at sharp acceleration. CONSTITUTION:A detector 7 is installed to detect the angle of a crankshft by 30 deg. ahead of the top dead center. If the degree theta1 of spark advancement is not more than 30 deg. below rotational frequency of 1,500rpm, the output signal of the detector 7 is used as a reference position signal to control the spark advancement when the rotational frequency is not higher than 1,500rpm. The output signal of another detector 2 is used as a reference position signal to perform spark advancement when the rotation frequency is higher than 1,500rpm. Below 1,500rpm, the fluctuation in spark advacement at slow rotation and the lag of the spark advancement are reduced to about 1/6. If the degree theta1 of spark advancement is 0 deg. and the period change is 20%, the lag at acceleration is decreased to 7.5 deg.. If the period change at slow rotation is 2%, the fluctuation is decreased to about 0.7 deg..

Ignition time controller for internal combustion engine

Abstract: PURPOSE:To prevent running performance and fuel consumption from deteriorating on highland, by compensating the deviation of required ignition time due to the fluctuation in the density of intake air. CONSTITUTION:The density and pressure of the air fall according to the increase in altitude. At that time, a spark advancement compensation means 7 expands and lengthens. As a result, the second breaker plate 6 is moved in a spark advancement direction (swung in the opposite direction to a cam 8) relatively to the first breaker plate 3 to increase the degree of spark advancement. The degree of the spark advancement by a vacuum spark advancer 2 following the weakening of negative pressure in highland running under the same load can be compensated through spark advancement by the spark advancement compensation means 7.