Research Development Corporation of Japan

Hitachi, Ltd.

Japan Science and Technology Agency

Fuji Electric Co., Ltd.

Kabushiki Kaisha Toyoda Jidoshokki Seisakusho

Japan Science and Technology Corporation

Kaneo Mohri

Toshihiko Matsuda

Junichi Oizumi

Mitsunari Kano

Yoshiharu Konishi

Morihiko Takashi

Jiro Kino

Osamu Saito

Mitsuo Yamashita

Yoichiro Kashiwagi

Masaki Mori

Hisashi Shiraki

Gen Sasaki

A method for producing a stress impedance effect element, the method including: connecting opposite ends of a magnetostrictive amorphous thin wire and respective electrodes by ultrasonic bonding; forming a groove in an elastic thin substrate having a thermal expansion coefficient equal to that of the magnetostrictive amorphous thin wire; installing the magnetostrictive amorphous thin wire in the groove; and bonding together the magnetostrictive amorphous thin wire and the elastic thin substrate by applying an insulating adhesive across the magnetoresistive amorphous thin wire.

Method for producing stress impedance effect element and that element

A prompt, accurate and highly practical drowsiness detecting device and a waking device operatively connected with the same are provided. Drowsiness of a vehicle driver or the like is detected to wake him/her up to prevent the drowsiness from causing an accident. A waveform of blinking is detected by a stress-impedance effect sensor head () positioned on a temple bow of a glasses frame in the vicinity of his/her temple, and the drowsiness is determined by a microcomputer (). Waking him/her up is accomplished by a milligauss AC magnetic field generator ().

Drowsiness detecting device and waking device operatively connected with the same

A magneto-impedance element includes an amorphous wire having a spiral magnetic anisotropy. A dc-biased alternating current is supplied to the amorphous wire, whereby a voltage is produced between both ends of the amorphous wire. The amplitude of the voltage varies asymmetrically with a variation in an externally applied magnetic field. The magneto-impedance element is compact, and has a high sensitivity and a high response speed.

Asymmetrical magneto-impedance element having a thin magnetic wire with

A magnetic sensor includes a DC power source, a multivibrator circuit composed of two CMOS inverters, a resistor, and a capacitor, each of the CMOS inverters being composed of a pMOS transistor and an nMOS transistor connected in series, and a magneto-impedance element. In a transition state attributable to switching operations of the CMOS inverters, a sharp pulse current is caused to flow through the magneto-impedance element so as to excite the magneto-impedance element sufficiently causing the skin effect, whereas in a steady state, the flow of the current is stopped by the CMOS inverters so as to reduce power consumption.

Magnetic sensor with CMOS multivibrator

In a bistable magnetic element, a pulse current or a dc-biased high frequency current is supplied to a soft magnetic material which has a helical magnetic anisotropy. As a result, the magnitude of a voltage induced across the soft magnetic material abruptly changes with respect to variation in an external magnetic field.

Bistable magnetic element and method of manufacturing the same

A magnetic field sensor for gradient field detection (gradient type magnetic field sensor) cancels relatively uniform disturbance magnetic fields (background magnetic fields) such as the terrestrial field through the use of two magneto-impedance elements, thereby making it possible to detect only a signal magnetic field (gradient field) which is considerably localized spatially. The magnetic field sensor includes a pair of sensor heads made of an amorphous wire, and a self-oscillation type electronic circuit for detecting a spatially uniform magnetic field or a differential value of a spatially gradient magnetic field by switching the direction of a bias magnetic field applied to the pair of sensor heads.

Differential magneto-impedance magnetic field sensor

A magnetic detector for detecting a magnetism present in the vicinity of or close to a magnetic wire circumferentially magnetized therein and an electromagnet for generating an A.C. magnetic field on the basis of the magnitude of a Matteucci-effect voltage developed across the magnetic wire when the electromagnet approaches the magnetic wire. A coordinate input device for detecting proximity between the electromagnet and an array of a plurality of such magnetic wires arranged in X and Y directions when the electromagnet approaches the array. A magnetic image sensor for detecting an intensity distribution of a static magnetic field to be detected and present along a longitudinal direction of the wire on the basis of a detection voltage of the wire when a plurality of such electromagnets arranged along the longitudinal direction of the wire are sequentially excited one after another.

Magnetic detector using Matteucci effect

A magnetostriction type torque sensor has a magnetostrictive film formed on an outer peripheral surface of a rotary shaft, a coil having a coil centerline extending in a radial direction of the rotary shaft, and a signal processor responsive to coil impedance. Since the coil includes a coil centerline extending in a radial direction of the rotary shaft, magnetic fluxes are formed mainly in a radial direction of the rotary shaft. Accordingly, the magnetic fluxes intruding deep into the rotary shaft are decreased, and the rate of the magnetic fluxes passing through the magnetostrictive film is increased. As a result, the magnetostriction type torque sensor comes to have high sensitivity even when the rotary shaft has high magnetic permeability or high electric conductivity.

Magnetostriction type torque sensor

Coordinate input device using Matteucci effect

A magnetic marker has a plurality of thin strips or wires of saturatable magnetic material having square .phi.-H characteristics and coercive forces different from each other. Amorphous magnetic material may be used. When the marker is subjected to magnetization reversal by an external magnetic field, variations of magnetic flux corresponding to a plurality of magnetization reversals can be chronologically detected as a voltage pulse train by detecting coils. By processing this voltage pulse train, a pattern can be made, recognized, so that the magnetic marker effectively identifies the kind of article to which it is attached. A magnetic marker reading and identifying apparatus has a plurality of exciting coils for producing a rotating magnetic field, with the axis of at least one of the exciting coils being orthogonal to the axis of at least one other exciting coil. The rotating a.c. magnetic field can be applied to the magnetic marker while the marker passes across the magnetic field irrespective of the position and direction of the marker, with no deviation in the pulse voltage due to leakage flux from the magnetic marker, thereby permitting reliable detection of the pulse train so that the kind and quantity of articles can be identified with high accuracy.

Growing community of inventors

Nagoya, Japan

Kaneo Mohri