Abstract: Method of determining the rotational speed of a machine having a drive into which a setpoint value for the rotational speed has been introduced and a rotational-speed sensor from which a measured actual value is obtainable, which comprises feeding the setpoint value to a mathematical model of a controlled system formed by the drive and the machine, deriving from the output of the mathematical model a computed actual value, determining the difference between the measured actual value and the computed actual value, forming the absolute value of the difference, and, if the absolute amount of the difference is exceeded, passing on the computed actual value, and if the absolute amount of the difference is not exceeded, passing on the measured actual value; and device for performing the method as the determined rotational speed of the machine.

Abstract: A capacitance length and/or angle measuring device has a transducer comprising a stationary part (1) forming a scale and a part (2) displaceable parallel over the surface of the scale, at a short distance therefrom and acting as a sensing unit. The opposite surfaces of the scale and sensing unit are provided with capacitor coatings (5,6,7,8,9). The mechanical quantity to be measured causes an area vibration of a capacitor, the capacitance variation resulting therefrom acting as a variable capacitive reactance in a circuit, which changes the phase position of the electrical signals. With an appropriate configuration of the capacitor surfaces one obtains a linear function between the mechanical quantity to be measured and the phase portion of the signals.

Abstract: For measuring the rotational speed of a wheel is an antilocking protected vehicle brake system a rotational speed sensor is provided in which in accordance with the rotational speed of the wheel signals are electromagnetically induced which have an amplitude and frequency which increase regularly with the rotational speed. When due to error sources the amplitude of the induced signal does not increase with the frequency of the signal a rotational speed measured value is determined by means of the measured amplitude, i.e. not on the basis of the measured frequency. To avoid erroneous measuring signals it may likewise be provided that when the amplitude of the signal does not increase with its frequency the last measured value of the frequency of the induced signal at which the amplitude still increased with the frequency is used to determine the speed of rotation.

Abstract: A method for computing a current vehicle speed value from a detected vehicle speed value derived from a pulse signal, said method provided data which can be used in a control process such as a cruise control of a vehicle, in which the current vehicle speed value is predicted from a previously computed vehicle speed value after an abnormal state of the current detected vehicle speed value is detected; and a cancel signal is produced for aborting the control process when the abnormal state has persisted for more than a certain time period.

Abstract: It is an object of the present invention to provide a method for controlling the vehicle speed during acceleration of a four-wheel drive vehicle, wherein the vehicle speed during acceleration can be determined with precision. According to the above method, even if a wheel is spinning, the vehicle speed can be correctly determined without any influence of the spin, by correcting the vehicle speed during acceleration by comparison of the determined second vehicle speed, based upon the lowest speed of the four wheels, with the first vehicle speed, which is determined based upon the wheel speed.

Abstract: A diagnostic system for detecting failure of rotational speed sensors incorporated in a central differential device of a four wheels drive vehicle for the purpose of controlling a lock-up clutch in the central differential device, wherein the rotational speed sensor for an output rotational member of the central differential device is checked, when the rotational speed detected thereby is lower than the rotational speed detected by the other rotational sensor, if the rotational speed detected thereby is continually zero over a period such as 10 seconds while the output of the other rotational speed sensor is above a certain low value.

Abstract: A speed detector, for use with a tone wheel having metal teeth, employs two coils positioned in offset relation near the tone wheel for interacting with the tone wheel teeth and thus changing their respective inductances. The coils preferably include iron cores to enhance magnetic coupling. One coil is in a phase sense oscillator circuit and the other is an a tuned sensor network. The oscillator is coupled to, and drives, the tuned network. The change in coil inductances effects a phase shift of the resulting signals in the oscillator and the tuned network, the magnitude of that phase shift typically being double that for a comparable single coil system. The output signals of the oscillator and tuned network provide inputs to a phase condition detector which looks for a reversal in their phase sequence and uses such event to provide timing reference pulses for a final determination of speed in a known manner.

Abstract: A synchronization indicator for a pair of rotating devices compares pulses generated by the two devices cyclically respectively pro-portional to their rotary speeds by using a predetermined count of one set of pulses to determine the then count of the other set and uses the count of the other set to cyclically provide a progressive indication of relative speed of the devices.

Abstract: An apparatus for electrically detecting the speed of a vehicle or the rotating speed of a wheel which is especially suitable for accurate speed detection in an anti-skid control circuit. This apparatus includes a rotor fixed on a rotating portion of the vehicle and provided with protruding timing teeth on the peripheral surface thereof at regular intervals and a sensor provided in the vicinity of the teeth of the rotor and not being in contact with the teeth of the rotor. The sensor detects the movement of the teeth with the rotation of the rotor electro-magnetically or by high frequency and outputs an electrical pulse signal as a speed detecting signal. In order to obtain accurate speed from the pulse signal, the center position of the pulse signal is obtained from both the output timing of the front or rear edge of the pulse and the pulse width, and the rotating speed of the rotor is calculated on the basis of the center position.

Abstract: A system and method for automatically running a vehicle at a desired cruising speed, in which a running resistance of the vehicle is always derived, a target opening angle of a throttle valve of a vehicular engine which can run the vehicle at a desired constant acceleration and/or at the desired cruise running speed is derived under the derived running resistance, and the opening angle of the throttle valve is controlled in a feedforward control mode so as to coincide with the target opening angle. The automatic cruise running system and method can achieve no variation of vehicle speed when the vehicle runs on a rugged road.

Abstract: Quadrature input signals from an opto-electronic or magnetic readhead which is movable relative to a periodically marked scale, are respectively multiplied by quadrature reference signals from a reference oscillator in multipliers. The resulting signals are added together in a mixer to give a signal (S) having a frequency which is the reference frequency shifted by the frequency of the input signals. This signal (S) is then compared with the reference signal. The reference signals are generated from a high frequency clock which is subsequently used to compare the period of the reference signal with that of the signal (S), giving outputs which interpolate the position of the readhead within the pitch of the marks on the scale.

Abstract: A device for detecting the rotational speed of a motor by a first rotational speed sensor and at least a second rotational speed sensor and a switch unit connected to the rotational speed sensors, the switch unit selecting signals from one of the sensors within a respective given rotational speed range.

Abstract: This invention is a means for detecting and logging the number of instances that predetermined speeds have been exceeded. This device can be used by car owners to monitor their driving habits as well as those of others using the car. Also the device of the present invention can be used by insurance companies in determining insurance rates based on driving performance.

Abstract: Disclosed is a vehicle speed control system for controlling the intake air amount introduced into an engine of a vehicle in order to allow the vehicle to travel at a target speed. The intake air amount is controlled in accordance with the integration value of deviation of the vehicle speed from the target speed. The integration value is rest when the vehicle acceleration is terminated and the reset integration value is derived on the basis of the vehicle speed and throttle valve opening degree. The vehicle speed control system includes an integral-added optimal regulator which determines the feedback amount on the basis of an optimal feedback gain predetermined in accordance with a dynamic model of the system relating to the constant travelling speed of the vehicle.

Abstract: An apparatus for measuring the wheel speed for an anti-skid control system of a motor vehicle, comprising a sensor for generating a pulse signal, the cycle of which corresponds to the rotational speed of the wheel. The wheel speed signal is provided in every control cycle having a constant time. If the wheel speed is not provided because the rotational speed of the wheel is low, the anti-skid control is performed in accordance with a compensated wheel speed calculated on the basis of the wheel speed measured immediately beforehand.

Abstract: A signal whose frequency is proportional to a rotational speed of a rotor and whose rising and falling angles near points crossing zero becomes larger with the rotational speed of the rotor is used to produce a first signal of amplitude corresponding to the rising and falling angles and a second signal of amplitude corresponding to the frequency, a difference between the first and second signals is evaluated, and the first or second signals are corrected with the difference.

Abstract: A method for monitoring of a tachometer signal is suggested, wherein the tachometer output signal is not only monitored with respect to its presence, but in addition also with respect to its plausibility. One exemplified embodiment may be realized with the assistance of a correspondingly programmed computer, wherein the tachometer signal change is checked to determine whether it is within predetermined limits. Furthermore, a possibility of reciprocating switching between erroneous and non-erroneous speed signals is eliminated.

Abstract: Rear warning lights on a vehicle are actuated in response to vehicular speed. When energized below a predetermined vehicular speed threshold, the warning lights will begin to flash alternately. The rate of flashing may be fixed so that each warning light flashes on briefly and at a fixed rate or it may be set to flash at a rate related to vehicular speed so that each warning light stays on longer as the vehicle speed decreases. At some very low vehicular speed, corresponding substantially to a full stop, the flashing may be set to cease so that one of the warning lights will glow steadily.

Abstract: A speed control system comprises a speed control unit and a test unit. The control unit has a Hall effect transducer for producing a signal representative of vehicle speed and a comparator for comparing that signal with a voltage reference source from which a control signal may be produced to control the vehicle throttle in the event of a disparity so as to maintain vehicle speed at a preset limit. The test unit is employed to set the voltage reference source.

Abstract: Plural independent delay lines are connected in parallel and receive a first signal taken from a first point. Samples of the first signal are taken at different sampling frequencies and are respectively stored in the several delay lines. Samples of a second signal are taken from a second point and are stored in a direct line at one of the frequencies. The correlation function between the samples of the direct line and the samples of one of the delay lines is calculated. Exemplary applications include measuring the speed of a linearly translating object, such as a web of paper.

Abstract: In an apparatus for detecting abnormal variation of wheels of a vehicle, a plurality of rotation sensors detect variations in rotation speeds of a plurality of wheels during running of the vehicle. Detection signals produced from the plurality of rotation sensors are converted into arithmetic operation signals by means of a signal converter. An arithmetic operation processor is responsive to the arithmetic operation signals from the signal converter to compute rates of variations in the rotation speeds. The arithmetic operation processor also compares the computed rates of variations with each other to decide whether wheels exist which have a rate of variation abnormally deviating from rates of variations of the other wheels. An alarm unit is responsive to decision signals from the arithmetic operation processor to alert abnormality of the wheels having the abnormally deviating variation rate.

Abstract: In a full time type four wheel drive power transmission system having a planetary gear mechanism for dividing input power supplied to the carrier into a first output power delivered from the sun gear for one pair of four wheels and a second output power delivered from the ring gear for another pair of four wheels or directly connecting the sun gear and the ring gear to the carrier by selectively rotationally connecting the sun gear and the ring gear by a clutch, the ring gear and the casing of the clutch are respectively provided with a series of teeth or other surface projections or unevenness, and two sensors are provided respectively to detect each unevenness for detecting rotational speed of the sun gear and the ring gear.

Abstract: To process the output signal of a rotational speed sensor (2) which generates an alternating voltage dependent in respect of frequency and amplitude on the rotational speed, two low-pass filters (TP1, TP2) serve to produce a useful signal (I1), on the one hand, and a reference signal (I2), on the other hand. The two signals are compared. In dependence on the difference of these signals (I1, I2) a pulse-shaped output signal, namely the processed sensor signal, is generated by means of a comparator (7). The reference signal dynamically follows the useful signal with the aid of a control signal issue by an adapter circuit (20,21).

Abstract: A level detector includes first and second comparators each having two inputs and an output wherein the first comparator receives an input signal and a first reference signal at the two inputs thereof and develops a first comparison signal when the input signal level is greater than the first reference signal level and wherein the second comparator receives the input signal and a second reference signal at the two inputs thereof and develops a second comparison signal when the input signal is less than the second reference signal level. A flip-flop includes first and second inputs coupled to the outputs of the first and second comparators, respectively. The flip-flop develops a high state signal when the first comparator develops the first output signal and develops a low state signal when the second comparator develops the second output signal.

Abstract: A frequency-to-voltage converter, as applied to controlling the speed of a motor, comprises: a motor speed encoder (1) producing first and second alternating signals (3a,3b) each at the same, first frequency which frequency is dependent on the said speed, the first and second signals being in quadrature with each other; a reference oscillator (4), for producing third and fourth alternating signals (5a,5b) each at the same, reference frequency, which frequency is higher than said first frequency, the third and fourth signals being in quadrature with each other; and single sideband modulating means (6,7,8) connected to receive the first, second, third and fourth signals and to produce a fifth alternating signal (8a) which is a frequency-shifted version of one of the first and second signals.

Abstract: In a speed detecting apparatus of a vehicle with an internal combustion engine whose rotational output is derived through a transmission, the apparatus comprises a circuit for calculating the gear ratio set in the transmission on the basis of the engine speed and a signal roughly indicative of the vehicle speed and a calculating circuit responsive to the result of the calculation in the circuit and the engine speed at each instant for calculating the speed of the vehicle at each instant. Thus, it is possible to accurately detect the vehicle speed at each instant in a short detection period.

Abstract: In the field of automated guided vehicles it is particularly important that speed and steering angle feedbacks be accurate and reliable. Any deviations in these feedback signals should be promptly detected and used to alter operation of the vehicle. An apparatus constantly monitors the time varying output signals of a pair of resolvers respectively associated with wheel rotation and steering angle. The loss of either of the resolver signals for more than a preselected duration of time related to the excitation frequency and vehicle speed results in the power delivered to an electric drive motor being discontinued and the vehicle brakes being applied.

Abstract: A vehicle speed control system comprises a memory which stores a signal Vr representing desired road speed which is compared in a comparator with a signal Vs representing actual speed. An actuator responds to any error by adjusting the engine to bring the vehicle to the correct speed. Units are provided to enable the driver to increment or decrement the stored desired speed by small amounts (e.g. 0.5 miles per hour). By means of switches, he can switch into the memory either one of two preset desired speed values. He can also modify these present values, by feeding in, instead, the actual road speed of the vehicle, such modified preset values remaining until the engine is next switched off. The system incorporates a "SOFT OFF" feature, by which, under certain switch off modes of the system, the engine power is not shut off abruptly but at a controlled rate. The system is advantageously implemented by means of a microprocessor.

Abstract: A resilient coupling between the rotor and output shaft of a brushless DC motor cooperates with a sensorless drive arrangement that obtains rotor position information from the voltage induced in the stator windings of the motor to reduce the effective inertia of the load and aid in starting of the motor.

Abstract: A pulse signal is generated by a wheel speed sensor with a frequency proportional to the speed of rotation of a vehicle wheel, the pulse signal comprising a plurality of frames each having a series of a predetermined number of pulses which are tended to be affected by noise and pulse mutilation. Pulses in each frame are counted and from the count is derived an instantaneous wheel speed value. The difference between the successively derived instantaneous speed values is taken and compared with a predetermined threshold. A first or a second indication is given in response to the difference being lower or higher than the threshold, respectively. If the first indication is given, output signals representing the average wheel speed and average wheel acceleration of the wheel are derived from the instantaneous speed values of successive frames.

Abstract: An improved reel servo for a recording and reproducing machine is disclosed. The reel servo as well as other servos in the machine are controlled by a single microprocessor which results in greater inherent communication between such servos and significantly improved operating capabilities. The reel servo itself is adapted to have the supply and take-up reels operate in different kinds of close loop servo control during various operating modes. The servo circuitry provides instantaneous information to the microprocessor for determining the diameter of tape that is wrapped on each of the reels. The reel servo has the capability of performing high speed shuttle and cueing operations without engaging the capstan and the tensioning arm can be positioned to provide the appropriate tape tension during shuttling in both the forward and reverse directions. An acceleration loop controls the supply reel so that the tape tension is maintained within predetermined upper and lower limits.

Abstract: A meter overdrive protection circuit is provided using a variable duty cycle drive pulse. Such meters usually comprise speedometers and tachometers used in highway vehicles such as trucks. A programmable pulse generator is utilized to provide a series of pulses of a selected width depending on the truck model. A sensor input corresponding to the rate of rotation of the drive shaft of the truck is used to trigger the pulse generator to produce each output pulse. Such output pulses are supplied to a meter drive which, based on the time average value of the output pulses received, displays an output value related to the rate of rotation of the truck drive shaft. Upon the triggering inputs exceeding a preselected frequency, a microcomputer will change the pulse generator operation to a fixed duty cycle operation whereupon the meter will be held to a full scale deflection. When the triggering inputs decrease below the preselected frequency, the pulse generator will be returned to a triggering output mode.

Abstract: A versatile system for preventing spinning of driving wheels, especially for commercial road vehicles, is provided by a braking control system in which a logic system responds not only to positive slip (overdriving) of each driven wheel, but also to negative slip (overbraking) thereof and, likewise, not only to over-acceleration, but also to excessive deceleration of the driven wheels. The cycle of control is started by an over-acceleration signal and terminates by the timing-out of a control phase in which hydraulic brake pressure is reduced. Within a control cycle, brake pressure builds up for a driven wheel in response to the simultaneous occurrence of any one of the following four pairs of conditions at that wheel: (a) presence of over-acceleration and of negative slip; (b) presence of over-acceleration and of positive slip; (c) presence of over-acceleration and absence of negative slip, and (d) presence of over-deceleration and of positive slip.

Abstract: The present invention provides a method and system for monitoring the rotor speed of the harvesting rotors of a cotton harvester. The inventive rotor speed monitor determines the rotational speed of each individual rotor. The individual speeds of the rotors are combined and an average rotor speed computed. The individual rotor speed is then compared with the average speed for the combined rotors. An alarm is provided to alert the operator whenever the rotational speed of a given rotor differs by a predetermined amount from the average rotational speed for the combined rotors. The invention rotor speed monitor can provide an early indication of rotor malfunction and also detours false signals generated by the harvester rotors deceleration after completion of the harvesting operation on a cotton row.

Abstract: A motor speed detector employs a magnetic sensor for detecting rotational movement of rotor armature segments of the motor and for producing real tachometer pulses in response to such movement. False tachometer pulses produced by extraneous non-rotor motor components are discriminated against to produce a signal representative of actual motor rotational speed.

Abstract: An electronic motor control system is taught herein which utilizes a tachometer check circuit. The tachometer check circuit is an electrical circuit which is interconnected with the output terminals of the tachometer. The circuit is utilized when the tachometer is at standstill to determine if the tachometer is functional, that is, is it internally correctly wired to produce an expected signal upon rotation. If such is the case, then motor start-up may take place. A second test is performed after motor start-up for determining if an appropriate amount of output voltage is being produced by the tachometer during the start-up phase. This is based on expected values of voltage during a short period of time after start-up. If such is not the case, the motor control system is disabled and the motor is stopped. The system is utilized for embodiments which include AC tachometers as well as DC tachometers used on unidirectional or bidirectional rotational systems.

Abstract: A speed detecting apparatus having a detector (101) for generating two sine-wave signals (PA, PB) which are .pi./2 out of phase with each other and have a frequency proportional to the speed of rotation of a motor so that actual-speed voltages (V.sub.L, V.sub.H) can be produced which are proportional to the speed of rotation of the motor. The speed detecting apparatus includes a quadrupling circuit and a frequency-to-voltage converter 107. Also included is a first speed generator for generating the actual-speed voltage (V.sub.H) in a high-speed range and a second speed generator which includes a four-phase rectangular signal generating circuit (106), a differentiating circuit (109), and a synchronous rectifier circuit (110) for producing the actual-speed voltage (V.sub.L) in a low-speed range. The voltages generated by the first and second speed generators are selectively issued as an output depending on whether the motor rotates at a high speed or a low speed.

Abstract: Speed detectors are provided for detecting speeds of each of the four wheels of a vehicle. An electric circuit is provided to compare the speeds of all wheels and to turn on at least one lamp when a difference between individual wheel speeds is detected, whereby slipping of wheels is indicated.

Abstract: In determining shaft rpm (revolutions per minute), a transducer generates a succession of output signals, corresponding to the successive passages of a shaft indicium through the transducer field of view. Processing circuitry is provided for selecting a sequentially successive pair of transducer output signals and for computing rpm therefrom. Updated rpm is computed from a further pair of sequentially successive transducer output signals, both non-sequentially successive to the earlier selected signal pair.

Abstract: A speed sensing apparatus (10) counts a predetermined number of gear teeth (18) on a gear (16) driven by a motor (8). The duration of time required to count the predetermined number of gear teeth (18) is compared to a timing signal of preselected duration. The comparison is used to make a determination as to whether the velocity of the gear is above or below a preselected velocity.

Abstract: An indirect speed sensor for an electric motor, such as an electric motor of the universal type, provides for a resistive element in series with the motor windings so that current pertubations that occur as a consequence of armature rotation are manifested as speed-dependent voltage signals across the resistive element. The voltage signals are amplified and filtered to remove frequency components above and below the expected signal spectrum and then provided to an analog-to-digital converter that converts the filtered analog signal to digital values that are stored in a memory. A stored-program controlled microprocessor analyzes the stored digital information by performing a fast Fourier transform to provide an equivalent amplitude spectrum. The maximum amplitude spectral component is then identified to determine the speed of the motor.

Abstract: A system for a four-wheel drive vehicle for automatically changing a power transmission of the engine of the vehicle from two-wheel drive system to four-wheel drive system in accordance with road surface condition and driving condition. The transmission system is provided for transmitting a power from the engine to two main driving wheels, and a clutch is provided for transmitting the power of the engine to drive two other wheels. Speed sensors are provided for producing output signals dependent on speeds of the four wheels, respectively. A steering-angle sensor is provided for producing an output signal dependent on the steering-angle. Computation circuits are provided to compute an actual slip rate from the output signals of the speed sensors and to compute a theoretical slip rate from the output of the steering-angle sensor.

Abstract: A device for indexing a rotor (17) of a machine (13) to be balanced utilizes the output signal (A) from a generator (15) connected to the machine rotor (17). The generator (15) produces a continuous sinusoidal output signal (A) proportional to the position and speed of the associated rotor (17). Detector means (37) detect a predetermined output from the generator (15) so that an indicator (41) issues an indication each time the detector means (37) detects the predetermined output. Thus, an operator can physically index the angular position of the rotor (17) with respect to the predetermined output (A) from the generator (15) when an indication is provided so that the position of the rotor (17) is referenced to the output signal (A) of the generator (15).

Abstract: A speed threshold value crossing detecting circuit which receives a pulse each time an object moves a unit distance has a time limit circuit activated by each pulse, a detector circuit determining whether the time limit of time limit circuit is over by the time of each successive pulse to detect whether the moving speed of the object has reached a preset speed, and a time limit control circuit for increasing the time limit of the time limit circuit when the detector circuit indicates that the preset speed has been reached. The hysteresis thus introduced in the time limit makes the detector circuit output turn uniformly on or off and suppresses the effect of small fluctuations in the pulse frequency not indicative of speed variations. Preferably the time limit of a retriggerable one-shot multivibrator is increased by selectively disconnecting an auxiliary resistor from the one-shot's RC time-setting network when the preset speed has been reached.

Abstract: A speed meter system for a vehicle which comprises a first pulse generator for providing pulses in accordance with the speed or engine speed of a vehicle, a first counter which is coupled to the first pulse generator for counting the number of pulses generated by the pulse generator, a second counter and a comparator coupled to the first and second counters for comparing the counts therein, the comparator producing a first judgement signal indicative of whether the count of the first counter is larger than or smaller than the count of the second counter and a second judgement signal indicative of the equality or inequality of the counts in the first and second counts. A gate circuit is coupled to the comparator for receiving the second judgement signal therefrom, the gate being opened when the second judgement signal indicates an inequality and closed when the second judgement signal indicates equality.

Abstract: Process for high-precision measurement of the phase relationship and phase displacement, respectively, of two pulse trains wherein rotational angles of two rotating bodies are quantized and converted by incremental shaft encoders into pulse trains, and the pulse trains are applicable for calculating the respective phase relationship and phase displacement, which comprises the steps of:a. counting the pulse trains in at least two different counters;b. forming a digital difference of the two counts;c. converting the digital difference into an analog signal;d. decoding the analog signal; ande. displaying the decoded analog signal;and a device for performing the process.

Abstract: An automatic driving wheel change-over apparatus designed to automatically effect a change-over between two wheel drive mode and the four wheel drive mode of a vehicle in accordance with the surface conditions of a road. When the difference in speed between the front and rear wheel exceeds a predetermined value during the two wheel drive, a clutch is operated for a predetermined time TM.sub.0, and when the clutch is operated more than four times during a predetermined time TI.sub.0 which is longer than the time TM.sub.0, the clutch is operated continuously for a predetermined time TH.sub.0 which is longer than the time TM.sub.0 thereby holding the vehicle in the four wheel drive mode.

Abstract: A digital shaft speed sensor modifies a clock frequency and counting period to provide a speed signal having wide dynamic range with adequate resolution. The division ratio of a programmable divider counting pulses from a shaft encoder is modified by a central processing unit based on the count or speed measured in a preceding counting. The output of the programmable divider sets an interval during which clock pulses are counted to determine the shaft speed. Since the dividing ratio of the programmable divider is dynamically changed according to previous speed measurements, the total number of clock pulses is correspondingly changed. In addition, the output frequency of the clock pulses is changed so that, at low speed, a low clock frequency can be used and at higher speeds, one or more higher clock frequencies can be used to maintain resolution with reasonable memory size.

Abstract: In a bar-graph type display method and system for automotive vehicle for monitoring an engine speed of the automotive vehicle and displaying the result of monitoring stepwise, when an indication level adjacent to the present indication level is detected a predetermined number of times successively, the present indication level is changed to the adjacent indication level, and when an indication level other than the present or adjacent indication level is detected the present indication level is changed to the detected indication level immediately.

Abstract: Disclosed herein is a magneto regulator circuit for regulating charging of the battery by the output of a magneto alternator. The regulator circuit includes a first circuit operative for connecting and disconnecting the battery in series with the alternator to allow or prevent charging of the battery. The first circuit includes a thyristor having a gate and operative when a trigger signal is applied to the gate for connecting the battery in series with the alternator to allow charging of the battery, a trigger switch which can be rendered conductive, subject to the battery voltage, for applying the trigger signal to the gate, and a shut-off switch for rendering the trigger switch conductive.