Showing papers on "Magneto published in 1984"

Multi-layer amorphous magneto optical recording medium

Abstract: A multi-layer magneto optical thin film recording medium is disclosed having very high carrier-to-noise ratios (at least 47 decibels) and high rotation angles. A transmission electron microscope photomicrograph (at 200,000 X) of one such medium is shown in FIG. 1. The magneto optic layer is a multi-phase amorphous material having magnetic anisotropy perpendicular to the plane of the thin film produced in a triode vacuum sputtering process at vacuums in the range of 4×10-3 to 6×10-4 Torr. Various transparent layers, such as dielectric intermediate and anti-reflective layers and a protective covering layer, are combined with the magneto optic layer and a reflective surface to yield media having enhanced carrier-to-noise ratio and magnetic optic angle of rotation.

Magneto ignition system, particularly for one-cylinder internal combustion engines

Abstract: To provide operating energy to an ignition instant control circuit, for example a microprocessor (22) which controls operation of a semiconductor switching stage (20) without detracting from the energy output of the magneto coil (14), the energy in the voltage half-wave (negative) which does not supply ignition energy is used to charge a storage capacitor (24) to a charging network (25, 26), with a limit being determined by a Zener diode (29); the ignition instant is calculated by the control circuit, typically a microprocessor (22), which receives operating energy from across the capacitor, and a control input at a control terminal (30) which is connected to an insulated gate semiconductor switch, typically an MOS-FET (31) having its drain (D) connected to the control terminal (30) of the microprocessor and through a coupling capacitor to the output terminal (24a) of the energy supply circuit; its source (S) connected to that one of the ignition winding terminals (14a) which is common to the energy supply circuit and the terminal of the capacitor (24) remote from the output voltage supply terminal (24a); and the gate (G) of which is controlled through a coupling network (33, 34, 35, 36) connected across the primary winding (14) of the magneto.

Modular, programmable high energy ignition system

Abstract: The ignition system for providing spark ignition to the cylinders of an internal combustion engine includes a generator assembly adapted to be mounted on said engine. This generator assembly includes a magneto adapted to be driven in response to the operation of the engine to provide output power and a timing unit including at least one rotatable unit driven in timing relationship to the operation of said engine. A control assembly is removably mounted on the generator assembly and incorporates an ignition control circuit connected to receive power from the magneto and operative in response to the timing unit to provide spark ignition to specific cylinders of the internal combustion engine. The control assembly is removable from the generator assembly without altering the timing relationship between rotatable unit and engine.

Measurement system for magneto-optic sensor materials

Abstract: A system for the measurements of magneto-optic properties of IR-transparent materials is described. The system is designed for the characterisation of fibre optic magnetic field sensor materials. M ...

Magneto-optic recording apparatus

Abstract: A writing, erasing and readout system for a magneto-optic record medium capable of achieving switching rates approaching the laser pulse rate, including at least two diode lasers (12, 14) operating through a single optical path and cooperating with bi-polar magnetic field producing means (50) located adjacent to and on the opposite side of the magneto-optic medium (54).

Anti-reverse operation of solid state inductive magneto

Abstract: Solid state inductive magneto ignition system with antireverse running circuit has a switching transistor connected in circuit with the primary of an ignition coil. A control circuit is connected for cutting "off" the switching transistor to generate ignition pulses. A first by-pass circuit for shunting current from the control circuit includes a silicon controlled rectifier (SCR) which is turned "on" by discharge of voltage from a capacitor in combination with a resistor which serves as a time delay to hold the by-pass circuit "on" for the duration of a voltage pulse developed by reverse running of the magneto. A voltage polarity sensing circuit for by-passing the by-pass circuit in response to a forward running pulse includes a silicon controlled rectifier (SCR) connected in parallel with the first SCR and a choke coil and a resistor to cause the second SCR to be turned "on" by a first negative pulse developed during forward running of the magneto.

Magneto resistive coupled thin films for magnetic flux sensing

Abstract: A preferred embodiment utilizing a magneto-resistive coupled film sensor for read back which saturates to allow writing.

Multi-layer amorphous optical recording medium

Abstract: A multi-layer magneto optical thin film recording medium is disclosed having very high carrier-to-noise ratios (at least 47 decibels) and high rotation angles. A transmission electron microscope photomicrograph (at 200,000 X) of one such medium is shown in Figure 1. The magneto optic layer is a multiphase amorphous material having magnetic anisotropy perpendicular to the plane of the thin film produced in a triode vacuum sputtering process at vacuums in the range of 4 x 10-3 to 6 x 10-4 Torr. Various transparent layers, such as dielectric intermediate and anti-reflective layers and a protective covering layer, are combined with the magneto optic layer and a reflective surface to yield media having enhanced carrier-to-noise ratio and magneto optic angle of rotation.

Magnetic generator for the ignition device of an internal combustion engine

Abstract: A magnetic generator for an ignition device of an internal combustion engine, in particular a magneto, has a rotating magnet flywheel, at least one permanent magnet and a stator, attached to the shaft of the engine, the said stator being provided with at least one winding and also being used to supply the other electrical loads on the motor vehicle, for which purpose a portion of the electrical energy from the ignition winding is used. The disadvantages of known embodiments are eliminated by means of an additional winding (4) which is connected in series with the generator winding (1). Loads (15) and a switch (16) with normally closed contact are connected in parallel to the additional winding (4). The additional winding (4) can be included in the main magnetic flux of the generator but can also be provided outside.

Magneto-optic modulation and measurement of Faraday rotation

Abstract: Main properties of magneto-optic modulators with single crystal films of garnets, the basic principle and the experimental installation of the measurement of Faraday rotation angle θ by means of the frequency doubling method of magneto-optic modulation are described. The means and merits of the measurement are presented, the results measured are discussed, and the measuring error is analysed. The Faraday rotation angle θ measured with the new moans is not effected by the light intensity change of a laser source and unstable factors of other devices in a optical circuit, so that the measuring precision is ±0.020°.

Magneto-optic analytical apparatus

Abstract: PURPOSE:To enable to continuously adjust the strength of the magnetic field using permanent magnets by an apparatus wherein rotatable permanent magnets are buried in a yoke for the main permanent magnet. CONSTITUTION:Upper and lower yokes 2, 3 are respectively provided above and below a main magnet 1. The lower yoke 3 is formed with two circular holes 14, in which permanent magnets 15 each having both pole parts in abutment with the inner periphery of the hole 14 and both side faces parallel to each other are rotatably buried. By properly rotating the permanent magnets 15, the strength of the magnetic field applied to the sample can be continuously adjusted.

Unsolved problems in magneto-electric BaMnF4

Abstract: Despite extensive low-temperature studies of the magnetic and ferroelectric properties of BaMnF4, three problems remain unsolved: 1.) an “extra” resonance line in the AFMR data is observed at low H as $$H is tilted away from 2.) there are several “extra” lines above the spin-flop field (H = 1.0T) with peculiar angular dependences; 3.) the predicted frequency dependence of the a-axis dielectric constant below TN. = 27 K is not verified experimentally.

Magneto-Inertia Confinement in Dynamic Z-Pinch

Abstract: An approach to fusion with z-pinch plasma of density 1020 cm-3 and of length 102 cm is discussed. A method of generating a 102 cm plasma column is proposed using a version of dynamic z-pinch with the help of a new electrode configuration.

The measurement of magneto-optic constants of thin transparent films

Abstract: An ellipsometric technique for measuring the magneto-optic constants of ferro- and ferrimagnetic materials is described. The necessary apparatus is outlined, and the equations necessary for data reduction are given. Unlike previous work, these equations permit the measurement of thin transparent films. Typical results on magneto-optic garnets are presented.