Abstract: According to the present invention, there is provided a direct current electric furnace for melting metal capable of melting scraps rapidly and also capable of diminishing cold and hot spots formed on the furnace wall, wherein the direct current electric furnace is provided with a single top electrode, a plurality of furnace bottom electrodes, or a plurality of electrode units obtained by dividing a multitude of furnace bottom electrodes of a small diameter into plural units, and electric current controlling thyristor circuits for controlling each individually electric currents flowing through the plural furnace bottom electrodes or electrode units. The electric current controlling thyristor circuits may be substituted by thyristor circuits for controlling electric currents for each of plural groups obtained by dividing the above plural furnace bottom electrodes or the above many furnace bottom electrodes or the above plural electrode units into the plural groups.

Abstract: A temperature measuring apparatus measures the temperature of a medium according to the propagation time of ultrasonic waves propagated for a predetermined distance through the medium. The apparatus has a transmitter 11, 12 for transmitting ultrasonic waves having a fixed frequency at predetermined timing and a receiver 13, 14, 15 for receiving the ultrasonic waves and providing a received signal. A delay time detector 24 detects, in response to the received signal, a delay time between the transmission and reception of the ultrasonic waves and a wave number calculator 21 calculates an integral wave number according to the delay time and a period of the ultrasonic waves. A phase difference detector 25 detects a phase difference between the transmitted and received ultrasonic waves modulating the received signal with a frequency that is sufficiently higher than the frequency of the ultrasonic waves.

Abstract: A device for detecting a transmissivity of a substance utilizing a transmitted light value, which comprises a light emitting element and a photo detecting element. The light emitting element and the photo detecting element are spaced from each other at a predetermined distance so that a transmitted light value of a substance passing through the space is detected as an amount of light transmitted therethrough. The photo detecting element further comprises a photo oscillator circuit including the photo detecting element as one component thereof and outputs a signal having characteristics selected from a cycle and a frequency corresponding to the transmitted light value, and when the condition of a substance exceeds a predetermined reference level, such information is displayed at a display unit.

Abstract: In an apparatus for controlling a headlight of a vehicle, a light from a preceding or oncoming vehicle can be detected without being disturbed by a light reflected on guardrails and the like, or light from a traffic signal, street lights and the like, and the illumination area of the headlight can be suitably adjusted without unnecessary switching of an illumination mode of the headlight. This control is carried out by receiving a light impinging on the front end of the vehicle by a light receiving member divided into a plurality of regions, by carrying out a comparison and discrimination between the light detection signals from the plurality of regions, and based on a result thereof, by selecting an appropriate illumination mode of the headlight.

Abstract: A direction detecting system comprises a geomagnetic field sensor for detecting the direction of the earth magnetism by two perpendicular components and a computing circuit for computing a direction and producing a direction signal from the electrical signals associated with the two perpendicular components from the geomagnetic field sensor. The computing circuit detects maximum values of distortions according to the distortion characteristics of the electrical signals associated with the two perpendicular components from the geomagnetic field sensor. Distortion amounts are computed and stored by the maximum distortion values and are used to correct the electrical signals from the geomagnetic field sensor.

Abstract: A method for displaying positional relation between the present running position of an automobile and a destination, on the basis of the wheel rotation signals generated by detecting rotation of left and right wheels of the automobile, setting signals selected at a starting position to represent a distance to the destination from the starting position and a direction of the destination from the starting point, and a direction signal indicating a running direction of the automobile.

Abstract: A device for displaying information concerning the travel route of an automobile vehicle includes a calculation unit for continuously monitoring the changes in the travel direction of the vehicle on the basis of the direction detected by the direction detection unit, and successively storing change signals corresponding to the amount of change in the travel direction of the vehicle, when the amount of change in the vehicle direction exceeds a predetermined amount, and a distance signal corresponding to the change signal, on the outward travel route, and generating a travel direction signal approximately at a predetermined distance on the basis of the stored change signal and the stored distance signal, on the return travel route. The vehicle travel direction, the distance, and the direction toward the destination or the starting point, and the distance toward a vehicle travel direction change point are displayed on fluorescent indicator tubes.

Abstract: A vehicle turn angle detecting device calculates an average value .DELTA..phi. of steering wheel rotation angle at every unit time together with a travelled distance .DELTA.L. And this device calculates a vehicle turn angle .DELTA..theta. at every unit time by using the equation shown below. By adding the calculated turn angles .DELTA..theta., the vehicle running direction to the standard direction can be detected..DELTA..phi.=K.multidot.tan.DELTA..phi..multidot..DELTA.

Abstract: A device for indicating information on the return route for an automotive vehicle includes a memory and control portion for successively storing the detected direction signals and the detected distance signals on the route to a destination and successively generating indication signals to the extent of a predetermined distance in the forward direction on the return route on the basis of the stored detected direction signals and the distance signals. The device also includes a circuit for correcting the difference between the distance of the vehicle travel on the route to the destination and the return route, so that the correct indication of information of the return route is displayed on a display device such as a CRT.

Abstract: A device and method for detecting the running direction of an automotive vehicle includes terrestrial magnetic field direction detection, vehicle steering angle detection, and response to the signals of these detectors for producing the vehicle running direction signal. In a computer, or equivalent circuitry, occurrence of abnormalities of the terrestrial magnetic field is decided when the relationship between the change in the vehicle running direction and the change in the steering angle does not satisfy a predetermined requirement.

Abstract: A heading detecting apparatus of the type which is installed in a roof of a vehicle including a magnetic member (a steel body) capable of having a remanence and includes a heading sensor positioned near the magnetic member, whereby the apparatus detects the terrestrial magnetism and thereby detects the forward heading of the moving objects the apparatus includes a permeability member positioned between the magnetic member and the heading sensor so as to reduce the effect of the remanence of the magnetic member on the detection of the terrestrial magnetism by the heading sensor.

Abstract: A heading detecting apparatus is attached to a moving object and includes a geomagnetic field sensor for detecting the direction of the earth's magnetic field in terms of orthogonal first and second signals and a computing circuit responsive to orthogonal first and second electric signals from the geomagnetic field sensor. In the computing circuit, when any one of the orthogonal first and second electric signals from the geomagnetic field sensor is a predetermined value, the value of the other electric signal is detected so that in accordance with the detected value an offset value is computed and stored, and the electric signals from the geomagnetic field sensor is corrected in accordance with the offset values.

Abstract: A magnetic field measuring apparatus including a magnetic sensor having an excitation winding and orthogonal first and second output windings for generating a first and a second output signal indicative of the orthogonal components of an external magnetic field, adjusting circuits for adjusting the amplitude and frequency of the sensor output signals, circuits responsive to common timing signals whereby the outputs of the adjusting circuit are subjected to sample-and-hold operation and A/D conversion and the resulting converted outputs are counted to generate count outputs, and a first and a second display unit for simultaneously displaying the count outputs.

Abstract: A vehicle's heading indicating apparatus includes a direction-finding sensor having a pair of external field sensing windings wound perpendicular to each other, a sensor exciting oscillator circuit, a signal sampling timing circuit, sample-and-hold circuits, comparators, a logic circuit and an indicator circuit. The output of each of the sensor windings is divided into predetermined (N+1) signal levels such that the heading or direction of travel of a vehicle is detected and indicated in accordance with the combination of each two signal levels sensing the heading, and also large disturbance of the earth's magnetic field is sensed such that the just preceding direction of travel obtained is indicated when the earth's magnetic field is excessively low or high.

Abstract: An apparatus for generating a parallel magnetic field by passing current through a coil cylindrically wound and shielded against the external magnetic fields by a magnetically shielded housing incorporating a fine meshed material such as a high magnetic permeability amorphous alloy. Inside the housing, there are provided a non-magnetic bobbin, on which the coil is wound, and a power source for providing current to the coil to produce a parallel magnetic field of an intensity corresponding to that of the current to be generated within the bobbin.

Abstract: An automobile running position indicator apparatus which comprises a device for generating a unit coverage distance signal each time the automobile has covered a unit distance, a device for generating a direction signal representing the automobile running direction at each time and a device for generating set signals representing the distance and direction from the starting point to the destination. A vectorical length from the starting point to the destination is operated from the set signals. The distance covered by the automobile is accumulated for each direction from the distance signal and the direction signal thereby to calculate a vectorial value length from the starting point to the present position. These vectorial values are used to determine a vectorial length from the present position to the destination, and the resulting vectorial direction and distance are displayed in the same display section.

Abstract: In a direction indicator including a direction sensor having an excitation coil wound on a core and two output coils wound thereon to cross at the right angles with each other, a direct current of given amount is supplied to the two output coils and a direct current magnetic field is produced so that the maximum values of the output signals is made equal by adjusting the gain of the output signals.

Abstract: A demagnetizer for removing residual magnetism in vehicles includes a single coil which is adapted to surround a portion or the whole of the body of a vehicle. A direct current and alternating current are supplied to the single coil simultaneously to produce a d.c. magnetic field and an a.c. magnetic field. The direction and magnitude of the d.c. magnetic field are so arranged, that the d.c. magnetic field cancels the external magnetic field. The magnitude of the a.c. magnetic field is varied within a predetermined range periodically to remove the residual magnetism.

Abstract: A direction finding system of the type finding a present direction on 4N direction divisions defined by 2N boundary levels for automotive vehicles, said system comprising a magnetic sensor circuit for generating a pair of electric signals indicating two perpendicular components of the earth's magnetic field, a logic circuit for signal-converting the electric signals, discriminating and latching to generate direction indicating 2N binary signals with reference to predetermined 2N boundary indicating levels, a sorting circuit for sorting the binary signals to generate one of 4N direction signals and a display device for displaying a corresponding direction.

Abstract: A method for displaying positional relation between the present running position of an automobile and a destination on the basis of the wheel rotation signals generated by detecting rotation of left and right wheels of the automobile, setting signals selected at a starting position to represent a distance to the destination from the starting position and a direction of the destination from the starting point, and a direction signal indicating a running direction of the automobile.