Showing papers on "Magneto published in 1990"

Integrated current sensor for current limiting and measuring - has components sensitive to magnetic field and excitation paths formed by film technique on substrate

Abstract: The current sensor uses a number of magnetic field sensors and associated emergising line conductors insulated from one another on a common substrate. The geometric arrangement is in a U, L or O configurationand usesa thin-film,thick-film or hybrid technique so that each magnetic field sensor is subjected to a fluxdensity proportional to the energising current. Each magnetic field sensor pref comproses a Hall element, a field plate, a magneto resistive sensor or a bipolar or MOSFET magneto transistor. ADVANTAGE-High miniaturisation.

Engine shut-down device

Abstract: An engine shut-down device is shown for an engine, having a magneto for generating an ac voltage in response to a speed of the engine, an ignition coil provided to ignite the engine, a driver responsive to the ac voltage for driving the ignition coil, and generator for generating an engine-stop signal The device includes a trigger responsive to the engine-stop signal for flowing a forward current from magneto to a ground when the magneto produces a positive value of the ac voltage and a backward current for a predetermined period of time from the ground to the magneto when the magneto produces a negative value of the ac voltage, an engine-stop section responsive to the backward current for flowing a short-circuit current from ground to the magneto to disoperate the ignition coil, so as to stop the engine

Magneto-optic information-carrying medium including three magnetic layers

Abstract: A magneto-optic information-carrying medium comprises three magnetic layers. A magnetic bias field is generated by a third layer which is premagnetized in the direction parallel to the thickness thereof.

Magneto-optic materials

Abstract: The growth of rare earth iron garnet single crystals and epilayers for magneto-optical 45° isolator application is described.

Magneto-optic materials.

Abstract: The growth of rare earth iron garnet single crystals and epilayers for magneto-optical 45° isolator application is described.

Enhancement of magneto-optical Kerr effects

Abstract: A general expression for the magneto‐optical polar Kerr effect is given for a bilayered configuration in which the optical constants of the two media differ. The equation shows that a giant enhancement of the Kerr effect in magneto‐optical/metallic bilayers can be expected if the dielectric constants of the two materials are low or are matched well to the other. An explicit equation is also given to calculate the spectral enhancement due to a dielectric overcoating on magnetic substrates. An example is given for SiO‐coated Dy/Co compositionally modulated alloys, yielding a good comparison to the experimental results in both the transparent and absorbing spectral regions of SiO.

Magneto-optical recording medium and magneto-optical recording system

Abstract: PURPOSE:To miniaturize and simplify means for impressing magnetic fields by providing a magnetic film having perpendicular magnetic anisotropy and a spin rearrangeable film on a transparent substrate. CONSTITUTION:The magnetic film 4 having the perpendicular magnetic anisotropy and the spin rearrangeable film 3 are provided on the transparent substrate 1. Since the spin rearrangeable film 3 assists the magnetization inversion of the magnetic film 4, information can be recorded with the small magnetic field. Namely, the magnetic field to be impressed at the time of recording and erasing in optical modulation recording to modulate the intensity of laser light can be made small, the decrease of the number of turns of an electromagnetic coil and driving current for generating the magnetic field and the use of an inexpensive permanent magnet are possible. Contribution is made in this way to the miniaturization, simplification and cost reduction of the magneto- optical recording device.

Dielectric layer for magneto-optic storage media structures

Abstract: A dielectric layer for use in a magneto-optic storage medium contains a compound glass of SiO2 -MO2, SiO2 - M2 O3, or SiO2 - M2 O5 and combinations thereof where M is selected from Zr, Ti, Al, Nb, Y, Sn, In, Ta and Sb.

A flywheel magneto arrangement.

Abstract: The invention has for its object to solve the problem associated with the use of a flywheel magneto for supplying ignition power to multiple cylinder combustion engines. The flywheel magneto according to the invention is composed of a flywheel (1) supporting magnets arranged in groups (2, 3, 4, 5-6, 7, 8, 9). The magneto flywheel (1) coacts with a multi-leg (11-20) core (10) of magnetically conducting material, the spacing or pitch of the core legs being such that the number of legs form an integer whereas half this number has to form an odd number. Within each group the magnets (2-9) are spaced in agreement with said core pitch. Said groups (2, 3, 4, 5-6, 7, 8, 9) are separated two pitches. Two adjacent core legs (11, 12) are provided with like windings (21, 22) the outputs ends (23, 24, 25) of the windings being connected to a discriminator circuit which distributes, in dependence of series of voltage polarities, trigger pulses (37, (37, 38) to ignition circuits (39, 40) for the respective engine cylinder (41, 42). The remaining core legs can accommodate, for example, generator windings (26).

Hybrid magneto-temperature sensor using contacts on a YBa2Cu3O7 - δ superconductor

Abstract: A new type of hybrid magneto-temperature sensor has been fabricated on the surface of YBa 2 Cu 3 O 7 - δ (YBCO) ceramics by creating two types of electrical contacts. The type 1 contact, made by the ultrasonic bonding method, showed nonlinearity below the superconducting critical temperature ( T c ) in its current-voltage (I – V) curve, which was sensitive to the magnetic field. This was applicable as a strict magneto sensor. The type 2 contact was made by the spot-welding method and showed non-ohmic contact in its I – V curve, and was not affected by the magnetic field at all. This was applicable as a strict temperature sensor. Integration of these two types of electrical contacts on YBCO ceramics make an excellent and simple hybrid magneto-temperature sensor device. The features of this sensor are: simple structure and simple fabrication process: very small size; high sensitivity to a low magnetic field; and simple integration of magneto sensor and temperature sensors.

Optical applied current transformer

Abstract: PURPOSE:To execute the measurement with high accuracy by making a supporting base for supporting a magneto-optical field sensor by a material whose linear expansion coefficient is about the same as that of the magneto-optical field sensor, and whose thermal conductivity is sufficiently small than that of a metallic material. CONSTITUTION:As for a material of a supporting base 20 of an optical applied current transformer, its linear expansion coefficient is about the same as that of a magneto- optical field sensor, and its thermal conductivity is sufficiently smaller than that of a metallic material. Also, the supporting base 20 is constituted so that a metal which is interposed between a magnetic shielding case 4 and an insulating cylinder 7 and comes into contact with a primary conductor is not exposed in an optical space transmission line. In such a constitution, when for instance, machinable ceramics is selected as a material of the supporting base 20, its linear expansion coefficient can be set about the same as that of lead glass, that is, the magneto-optical field sensor 3. Accordingly, even if the magneto-optical field sensor 3 stuck to the supporting base 20 is used at a temperature being different from a temperature at the time of adhesion hardening, no stress is applied and a photoelastic effect is not generated either, and an optical axis fluctuation of an optical space transmission part is reduced.

Solid state current measuring system for television pre-payment meters

Abstract: An isolated solid state current measuring system for use in television pre-payment meters detects when a television receiver changes from a standby to an operating mode. The current detector may include a Hall effect sensor or a magneto resistive sensor.

Magneto-optic recording system

Abstract: An apparatus (10) for providing a bias magnetic (18) field coincident with the read/write laser (15) in a magneto-optic recording system is disclosed, with special utility for systems wherein the thickness or configuration of the media (28) necessitates a functioning bias magnet (18) being located on the same side of the media (28) as the read/write laser (15).

Magneto=optical record carrier - has magnetic thin film on dielectric layer which prevents corrosion of ferromagnetic thin film in air

Abstract: The magneto optical data encoder has a substrate, covered with a dielectric layer (2) of SiAINO and a magnetic thin film (3), which has an axis of easy magnetisation, running perpendicularly to a surface of the substrate. The SiAINO layer stops background reflction in the data encoder and increases the likely Kerr co-ordinate. All this improves data encoder and/or replay qualities. The SiAINO layer prevents corrosion in the ferro-magnetic thin film, if the magneto optical data encoder is left open to the atmosphere. USE/ADVANTAGE - Creates magneto opical corrosion-resistant carrier no reduction during reply or signal-to-noise ratio, improved by fitting dielectric film between magnetic film and substrate.

Magneto static wave device

Abstract: PURPOSE:To reduce insertion loss by installing a transducer for exciting magneto static waves onto the side face of a magnetic film and exciting magneto static waves. CONSTITUTION:Transducers 7 are mounted in contact with both sides of a magnetic film 6 formed onto gadolinium-gallium-garnet (A GGG substrate as an abbreviated name) 10 and connected by circuits to strip lines 8 respectively as a method preventing the lowering of the efficiency of excitation of the transducers by the reflection of microwaves from the terminal section of the magnetic film. When resonance frequency determined by the material characteristics of the magnetic film 6 and an external DC magnetic field and the frequency of microwaves applied to the strip lines 8 coincide, resonance is generated, and the microwaves of the frequency can be propagated in low loss.

Application of IR-magneto optics and optics for the determination of doping profiles in semiconductors

Abstract: A physical model is presented for the non - destructive determination of free carrier density profiles. The accuracy of the method with respect to quantitatively determine the profile function is enhanced by using the asymmetrical IR - reflectivity and the IR - transmission as well as 6 different measurable differential magnetooptical interference effects caused by the same free carrier profile. The results are compared with other methods used to determine profile functions such as SIMS, spreading resistance, Rutherford backscattering and stripping Hall measurements.