Abstract: The invention is directed to a method and an arrangement for controlling an internal combustion engine wherein the air flow to the engine is influenced at least in component ranges and in a selectable time reference to operations in the engine.

Abstract: The invention is directed to a method and an apparatus for measuring the air-flow rate in the intake tube of an internal combustion engine using a flow-measuring device which is insensitive to the direction of flow. In order to avoid incorrect measuring results when pulsations of the air flow occur, the reverse flow is sensed and, based on a total flow signal, deducted to determine the forward flow. At the points where the direction of flow is reversed, certain physical relationships prevail between flow-measuring signal, differential pressures, the presence of maxima and minima in the flow signal and the gradient of the flow signal. Several methods are disclosed to determine these reversal points as are flow charts for a computer-controlled determination of the air-flow rate.

Abstract: A control device having certain criteria which must be fulfilled in order to trigger an acceleration enrichment. Criteria are a defined number of successive load values of increasing tendency and/or an actual load value with a defined distance above the arithmetic mean of a number of preceding load values. For the acceleration enrichment itself operational parameters, such as rpm, load, load gradient, temperature and number of revolutions since the triggering of the acceleration are processed.

Abstract: To permit simple computation of control parameters, for example by an engine microcomputer, operating parameters of the engine are signalled by sensing instantaneous operating conditions such as speed, induction air pressure, or the like, preferably at a sensing angle of the crankshaft in advance of top dead center (TDC) position of a reference piston, and the average value is then determined by weighting the sensed instantaneous value to relate it to an average value in a weighting circuit (16). Preferably, the sensed signal is additionally modified in a function generator (15) as a function of then pertaining average conditions of at least one of: speed n; loading L.

Abstract: An electromagnetically excited vibrator with arms carrying baffle members at their ends that are immersed in the flow to be measured is mounted at one or more vibration nodes to reduce loss of vibratory energy to the casing of the flow meter. A flat magnetically conducting cross shape can be mounted at a node in the middle, provided each cross beam of the cross is vibrated in flexure, and the two cross beams vibrate in phase opposition (counter stroke). Such a vibrator is excited by a similarly crossed pair of E-shaped cores with exciter and secondary windings on the middle legs of the cores, or by a coaxial re-entrant core with permanent magnet wafers set in the rim at respective locations separated by an air gap from the arms of the cross. In each case the vibrator can be firmly affixed to the central leg or legs of the core.

Abstract: The mass flow rate of a fluid, for example a gas or air, for example passing through a duct or the like, is determined by placing a vibrating element in the path or stream of air flow, and measuring the damping thereof due to the air flow; the damping can easily be measured, in accordance with the invention, by connecting the vibrating element in a circuit having a servo system including a controlled variable amplifier and a comparator, such as a proportional-integral (PI) controller (14) comparing the signal on the vibrating element with a reference establishing a vibrating amplitude and, in turn, controlling the amplification of the variable amplification amplifier (8) to maintain a constant amplitude of vibration, the control signal controlling the variable amplification amplifier being a measure of the damping, and hence of mass flow rate.

Abstract: The knock sensing equipment has a control circuit which generates gating signals for dividing the operation into a measuring phase and a test phase. In the latter, the possible malfunction of the sensor is determined. During the test phase, the sensor responds either to background noise or to a test voltage and the sensing output signals are compared to a predetermined minimum and/or maximum level. Malfunction is indicated if the signals furnished by the sensor are outside of the indicated range.

Abstract: A voltage-frequency converter having a chargeable and dischargeable memory, a comparator circuit and a subsequent multivibrator, wherein the charging and/or discharging signal for the memory is obtained from special signal sources. At constant charging and discharging signals, a linear voltage-frequency conversion is provided. In the case of variable charging or discharging voltages, non-linear signal conversions are possible. The multivibrator may be a digital monostable multivibrator, to effect precise, reproducible and quantifiable period durations in the output signal of the converter, and thus a very precise voltage-frequency conversion.

Abstract: Signals from a coil producing pulses in response to flux variations produced by a rotary member driven by an engine crankshaft are applied in push-pull through series resistors to the inverting and non-inverting inputs of a comparator. A variable voltage divider for the input signals is provided by a pair of complementary transistors respectively connecting the comparator inputs to opposite poles of a fixed voltage supply. The comparator pulses charge a capacitor through a transistor, the capacitor being periodically discharged through a resistor, once per crankshaft revolution. An increase of capacitor voltage beyond a very small amount progressively lowers the resistances provided by the transistors connected to the comparator inputs, acting on one of them simply through a transistor and on the other through a transistor and a current mirror circuit.

Abstract: To positively allocate output signals from a transducer scanning marker elements arranged at a uniform distance from the center of a rotating disk, the markers are located around the circumference of the disk in accordance with a predetermined pattern, for example, uniformly distributed 30.degree. apart, or distributed with uniformly increasing relative distances, and an additional market element (33) and forming a reference marker is located in the zones between adjacent markers spaced from a neighboring marker element (21) of the plurality of marker elements by a distance which is substantially larger than the angular distance with respect to the marker element at the other side of the reference marker. The outputs from a pick-up sensor are evaluated by applying the outputs to two counters, counting a different clock rate, the count output of one of the counters being stored and compared with a subsequent count state of the other counter operating at a higher clock rate.

Abstract: A fuel metering apparatus in an internal combustion engine is proposed, in which the metering signal is correctable in accordance with the mixture composition and/or the exhaust gas composition, this composition is detected by means of a sensor for at least one component of the mixture and/or exhaust gas, and the sensor signal proceeds to a single threshold switch for evaluation. The output level of the threshold switch is monitored in its course and the correction signal as well as an error recognition signal are derived from it.

Abstract: An apparatus for controlling the current through an electromagnetic injection valve of an internal combustion engine during its pickup and holding phases by opening and closing a first switch connecting the valve to a voltage source. The first switch is initially closed by a valve timing circuit to initiate pickup of the valve. A first current-sensing resistor connected in series with the first switch produces a signal to open the first switch when the valve current attains an upper threshold value which assures valve pickup, and to close a second switch connected in series with a second current-sensing resistor across the valve. When the valve current drops to a lower threshold value greater than the valve drop-out current, the second current-sensing resistor produces a signal to reclose the first switch and open the second switch for a predetermined time, after which the first switch is again opened and the second switch closed.

Abstract: To supervise a program controlled device which is subject to stray noise or disturbance pulses, particularly microprocessor controlled automotive vehicle electronic systems, a timing circuit is provided responsive to check pulses added to the program and defining a timing interval, the monitoring system distinguishing between disturbance pulses and static defects by supervising the control pulses and, upon failure of the control pulses, generating a program restart or interrupt signal, respectively, which both initiate a new start of the program cycle or, respectively, define a timing interval which, upon failure to sense further control pulses, initiates energization of an emergency switching system. Continuous failure to receive control pulses also can initiate the emergency switching system.

Abstract: In order to suppress the train of detector oscillations after the disappearance of the engine knock phenomenon, the invention provides a piezoelectric oscillator which is set into vibration by engine knock and includes circuitry for applying signals of opposite polarity to the oscillator at times when no engine knock is expected. Accordingly, the output of the piezoelectric engine knock detector is used only in a relatively narrow time interval during the combustion cycle. In the remaining interval, the circuit switches over to a configuration where the oscillations of the piezoelectric oscillator are damped. The construction of the invention makes it possible to discriminate between different cylinders of a multi-cylinder engine and to assign the knock phenomenon to particular engine cylinders. A number of embodiments is presented.

Abstract: Data signifying the value of a controlled parameter which varies as a function of engine speed is stored on a disk rotating with an engine shaft. A sensor senses the data starting with a predetermined reference position and extending over a predetermined fixed scanning time. Since the time is fixed, the angle of rotation covered by the sensor will vary as a function of engine speed. The data is so arranged along the disk that the value of the parameter at the given speed can be determined from the sensed data at the end of the scanning time. The data is stored either as markings to be sensed serially from the start to the end of the scanning time, or is stored in parallel tracks to be sensed simultaneously at the end of the scanning time.

Abstract: A pair of marker signals are generated with respect to a predetermined crankshaft position; the leading edge of the marker signal is used as a control edge to generate, by digital calculation, a digital control signal calculated in accordance with engine operating characteristics, as related to speed, loading, and the like, and providing a numerical output value used as a control value to control the timing of a pulse which may, depending on use, control: ignition timing; fuel injection timing; transmission gear shifting, the data relating engine performance, with respect to loading, speed, and other parameters such as temperature, starting conditions, and the like, being stored in a data memory. Calculation of the digital control signals and determination, by timed sequential counting out, are carried out independently from each other and during time overlap.

Abstract: Operating parameters, such as speed and loading of the engine are converted in electrical signals which are converted into pulse rates, to control counting of an address counter, addressing a read-only (ROM) memory in which characteristics of the engine are stored. To provide easy introduction of additional parameters such as temperature, idle condition, maximum speed, start condition, etc., the final value of an accumulator counter, the number of which at a given time controls the ignition timing, can be changed; further, to simplify the system, the speed and load signals are processed during a portion of the time between successive ignition events, the remaining portion of the time being controlled solely by one of the parameters (preferably speed), thus simplifying the circuitry by providing a transfer switch connecting for the remaining period only the selected (preferably speed) signal to the accumulator counter, the count state of which controls the ignition instant.