Abstract: A circuit and method for magnetic field detection is disclosed. A fluxgate sensor comprises a fluxgate having a first core and a second core. A sense coil has a first winding around the first fluxgate core and a second winding around the second fluxgate core. A fluxgate detection circuit is coupled to the sense coil and outputs a signal proportional to an external magnetic field applied to the fluxgate. A detection circuit is coupled to the first winding and outputs a signal that indicates whether voltage pulses have been detected on the first winding.

Abstract: A system and method configured to measure applied force and pressure on a load cell. The system includes an axial force pressure transducer having a hollow cross section comprising at least two strain sensitive regions, and a plurality of strain sensors connected to the at least two strain sensitive regions, wherein applied force and pressure is calculated based on strain measurements using mathematical formulae. A method of calibration of the axial force pressure transducer using known applied force and pressure measurements to calculate a calibration matrix reflecting the strain sensitivities of the at least two strain sensitive regions.

Abstract: An inspection circuit serves as a pseudo circuit of a flux gate-type magnetic element having an excitation coil and a detection coil and inspects a magnetic field detector that detects a magnetic field based on an output of the magnetic element when detecting an intensity of a stationary magnetic field applied to the magnetic element based on a time-resolved magnetic balance type. The magnetic field detector includes: an excitation signal generation unit, a detection signal comparison unit, a feedback signal conversion unit, a feedback signal adjustment unit, a data signal conversion unit, and an excitation signal adjustment unit.

Abstract: A magnetic element control device of the present invention includes an excitation signal generation unit that generates an alternating signal, an excitation signal adjustment unit that generates an alternating voltage signal from the alternating signal, and generates an excitation signal which is applied to an exciting coil on the basis of the alternating voltage signal, a detection signal comparison unit that detects a detection signal of a positive voltage or a negative voltage which is generated by an induced electromotive force when a current direction of the excitation signal switches, and a feedback signal adjustment unit that generates a feedback signal for applying a magnetic field, cancelling a stationary magnetic field which is applied to a magnetic element from voltage information, to a feedback coil.

Abstract: Provided is a magnetoimpedance (MI) sensor having a high magnetic sensor sensitivity and a wide measurement range. The MI sensor comprises an MI element, an electric current supply unit and a signal processing circuit. The MI element comprises a magnetosensitive wire formed of an amorphous soft magnetic alloy having zero magnetostriction, and a detection coil provided around the magnetosensitive wire with an electric insulator disposed therebetween, thereby detecting voltage generated at the detection coil and corresponding to an external magnetic field upon application of a high frequency electric current to the magnetosensitive wire. The electric current supply unit supplies the high frequency electric current to the MI element. The signal processing circuit processes an output signal from the detection coil.

Abstract: A physical properties detection device comprising a probe to be placed near or touching a surface of a ferroelectric; an oscillation loop including the probe and capacitance within the ferroelectric; and detection means for detecting a physical properties of the ferroelectric on the basis of a frequency variation of a measurement signal generated in the oscillation loop, the frequency variation accompanying application of an alternating electric field to the ferroelectric; and the physical properties detection device is further comprising frequency conversion means for converting the frequency of the measurement signal to a low frequency and outputting the resulting signal as a converted measurement signal; frequency control means for controlling the frequency of the converted measurement signal so as to match a target frequency; frequency detection means for generating a frequency detection signal that has a signal level corresponding to the frequency of the converted measurement signal; and synchronous dete

Abstract: There is provided a thin film tri-gate fluxgate for detecting a component of a magnetic field in directions of three axes, the thin film tri-gate fluxgate comprising: two first thin film fluxgates of a bar-type disposed on a plane for detecting horizontal components of the magnetic field in direction of dual axis; and a plurality of second thin film fluxgates for detecting a vertical component of the magnetic field, wherein each of the first thin film fluxgates and the plurality of the second thin film fluxgates comprises a drive coil for applying a power, a pickup coil for detecting a voltage and, a magnetic thin film, and wherein the plurality of the second thin film fluxgates are substantially perpendicular to each of the first thin film fluxgates wherein a length of the magnetic thin film of each of the plurality of the second thin film fluxgates is shorter than that of each of the two first thin film fluxgates, and wherein two end portions of each of the plurality of the second thin film fluxgates is wid

Abstract: Disclosed is a method of analysis of a mixture of biological and/or chemical components that entails spatially arranging a chosen component attached to magnetic particles, exposing the particles to a magnetic field, and recording a magnetic induction signal, from which the content of the analyte in the mixture is judged; this includes grouping the chosen component in a probe volume, making the magnetic field alternating, pre-setting its spectrum, at least, at two frequencies, and recording the signal at a frequency, which is a linear combination of these frequencies, during the exposure of the magnetic particles to the field.

Abstract: Disclosed is a method of analysis of a mixture of biological and/or chemical components that entails spatially arranging a chosen component attached to magnetic particles, exposing the particles to a magnetic field, and recording a magnetic induction signal, from which the content of the analyte in the mixture is judged; this includes grouping the chosen component in a probe volume, making the magnetic field alternating, pre-setting its spectrum, at least, at two frequencies, and recording the signal at a frequency, which is a linear combination of these frequencies, during the exposure of the magnetic particles to the field.

Abstract: A two-axis geomagnetic sensor is disclosed. The two-axis geomagnetic sensor includes a first geomagnetic sensor part including a first wafer and a first geomagnetic sensor on a surface of the first wafer; and a second geomagnetic sensor part including a second wafer and a second geomagnetic sensor on a surface of the second wafer. The first and second geomagnetic sensor parts are bonded to each other, in which the first and second geomagnetic sensors positioned in an orthogonal relation to each other. Accordingly, an occupancy area of the geomagnetic sensor can be reduced. Further, the geomagnetic sensor on each axe can have the same magnetic material properties, and alignment deviation cannot be generated.

Abstract: An eddy current inspection system and method for inspecting a component is provided. The system includes an eddy current probe for sensing eddy currents from the component and an analog to digital converter configured for converting eddy currents to digital signals. The system also includes a processor configured for generating an eddy current image from the digital signals and pre-processing the image to enhance a quality of the image. The processor is configured to identify regions displaying flaw patterns and calculating a defect characterizing parameter for the identified regions.

Abstract: The present invention is a magnetic field detection device that makes use of a frequency characteristic affording circuit in order to selectively detect magnetic signals from a frequency domain accurately at a high level of sensitivity. The present invention has a magneto-impedance element, a detector coil and a negative feedback coil which is wound around the magneto-impedance element, and a frequency characteristic affording circuit which affords a frequency characteristics on the negative feedback signal of a negative feedback connecting an output terminal thereof with the negative feedback coil. Using filters as the frequency characteristic affording circuit, the following are possible uses of this magnetic field detection device: a geomagnet detection device for earthquake prediction (using a high-pass filter), a bill validation apparatus for vending machines, etc. (using a low-pass filter), and a magnetic oscillation detection device for a magnetic gate system (using a band-reject filter).

Abstract: A digital synthesizer generates an electrical digital carrier that drives probe coil to generate an electromagnetic wave propagated into a test material proximate the probe coil. A return electromagnetic wave generated by eddy currents in the material includes signatures of material defects modulated on the return carrier electromagnetic wave. The return wave is detected by one or more probe coils, amplified, converted from an analog signal to a digital signal and then digitally mixed with digital sine and cosine functions also generated by the digital synthesizer to yield sum and difference values, mathematically expressing various eddy current signals received by the probe in a complete set of orthogonal functions. A low pass filter then removes all but the difference values. A direct current reference component is subtracted from the mixed digital signal, which translates the signal to center about a zero axis for ease of display and analysis.

Abstract: A fluxgate sensor integrated in a printed circuit board. The fluxgate sensor has soft magnetic cores having a lower core and an upper core mounted on the lower core, for forming a closed magnetic path on a printed circuit board, an excitation coil formed as a metal film, alternately winding the upper and the lower soft magnetic cores substantially in a number ‘8’ pattern, and a pick-up coil formed as a metal film, having a structure of winding the upper and the lower soft magnetic cores substantially in a solenoid pattern, the pickup coil being placed on the same plane as an external contour of the excitation coil.

Abstract: A road vehicle sensor provides an output signal having a magnitude which varies with time through a plurality of values as a vehicle passes the sensor. Signal processing apparatus monitors the timing of sensor signals generated from sensors in adjacent lanes of a highway and provides an indication when such sensor signals could correspond to a double count with a single vehicle being detected by both sensors. Then, the geometric mean of the amplitudes of the sensor signals from the sensors in adjacent lanes is calculated and is used to indicate a double count if the geometric mean is below a threshold value. Signal processing arrangements are also described to detect tailgating vehicles which may be simultaneously detected by a sensor, and for determining the length of slow moving or stationary traffic.

Abstract: The present invention relates to a magnetic sensor apparatus which is capable of detecting a very weak magnetic field even when the DC bias magnetic field is at zero and greatly reducing detection output occurring due to factors such as inconsistency of a magnetic body, temperature fluctuations, distortional fluctuations and drift. A magnetic sensor element S generates a pulse-type signal which is in proportion to a rate of change of the magnetic permeability of a magnetic body M and the size of an external magnetic field at a detection winding Wd. A drive circuit 11 cyclically changes the magnetic permeability of the magnetic body by supplying a pulse-type drive current for sampling to the magnetic body. A peak value detection unit 12 detects a positive peak value and a negative peak value of the pulse-type signal.

Abstract: A magnetic sensor includes a magnetic core, an excitation coil, an oscillator and an excitation circuit, a detection coil, and a latch circuit. The excitation coil is wound on the magnetic core. The oscillator and the excitation circuit repeatedly supply a rectangular wave excitation current having a given polarity to the excitation coil. The detection coil is wound on the magnetic core on which the excitation coil has been wound. The detection coil generates an output signal having peaks of opposite polarities corresponding to magnitudes of a target measurement magnetic field in response to leading and trailing edges of the rectangular wave excitation current.

Abstract: A method and apparatus for detecting power lines including a pickup coil for detecting the magnetic field generated by the current conducted by a power line and for producing a sense current in response to the detected magnetic field, a gyrator circuit for generating a sense voltage in response to the sense current and tuning means for producing an output voltage in response to the sense voltage such that a power line can be detected thereby. The tuning means also tunes the power line detecting apparatus to the predetermined frequency of the current conducted by the power lines. The power line detecting method and apparatus also preferably analyzes the magnitude and frequency of the output voltage produced by the tuning means so as to distinguish output voltages generated in response to the magnetic fields produced by power lines from those generated by extraneous electromagnetic noise.

Abstract: In a magnetic inspection apparatus for a thin steel strip of the invention, a pole-to-pole distance of a magnetizer, which is housed in a hollow roller contacting a traveling thin steel strip to oppose the thin steel strip, is set between twice and eight times a distance between magnetic poles and the thin steel strip. A position of a magnetic sensor in the travel direction of the thin steel strip is shifted from the central position of the magnetic poles to a travel direction side by a small distance. In this invention, a pair of hollow rollers are provided to sandwich upper and lower surfaces of a traveling thin steel strip, and magnetic sensors are respectively housed in the hollow rollers. As a result, a position of a defect in the direction of the thickness of the thin steel strip, and a defect size can be accurately detected.

Abstract: The present invention relates to an antidegradant system comprised of (A) an antidegradant selected from the group consisting of phenolic antidegradants, amine antidegradants and mixtures thereof; and (B) a unique polymerizable synergist. In addition, there is disclosed a stabilized polymer comprising (A) a polymer selected from the group consisting of (1) homopolymers and copolymers of monoolefins; (2) natural rubber; and (3) synthetic rubber derived from a diene monomer; (B) from about 0.05 to about 10 parts by weight based upon 100 parts of polymer of an antidegradant selected from the group consisting of phenolic antidegradants, amine antidegradants and mixtures thereof; and (C) from about 0.05 to about 20 parts by weight based upon 100 parts of polymer of a unique polymerizable aromatic sulfide synergist.

Abstract: A device for measuring a magnetic field which is constant or varies over time, includes at least one core (3, 4) consisting of a material having high permeability, a coil (5, 6) for the magnetization of this core via an alternating current source (I) connected to the coil, and at least one measuring coil (7, 8) in which a voltage is induced corresponding to the magnetic field resulting in the coil produced by means of the applied alternating current and the external magnetic field to be measured. In order to measure very small magnetic fields and relative changes in the fields, an integrating device (9) connected with the measuring coil (7, 8), an arrangement for subtracting the d.c. voltage component from the alternating voltage component of the measurement voltage (U.sub.ai) and a device for detecting the peak values of consecutive half-waves of the output signal (U.sub.x) of the subtracting arrangement (13, 10) are provided.

Abstract: A magnetic direction detecting apparatus has a magnetic sensor head composed of a magnetic core, an exciting coil wound around the core and a pair of detection coils diametrically wound around the core perpendicularly to each other; an oscillator for supplying a rectangular current wave of a single polarity to the exciting coil; and a switching gate openable synchronously with the rectangular wave for permitting only peaks of the same polarity to pass therethrough. The detection of a magnetic direction by using this apparatus does not suffer from restrictions in switching gate-opening timing.

Abstract: A driver circuit for a fluxgate magnetometer has a repetition rate controble independent of the magnetometer core winding inductances, and a current-ON interval terminated only by core saturation. In this manner, power consumption is greatly reduced as compared to prior magnetometers without sacrificing low-noise operation. Previous drivers operated in a free-running flyback mode at high pulse repetition rates. The present driver reduces the oscillator repetition rate, and power consumption, by the use of a control loop from the flyback oscillator which signals the end of a current pulse as the magnetometer core rebounds from the saturated state.

Abstract: A magnetic field sensor is illustrated which in one useful application comprised two orthogonally positioned coils each having its own electronics and each wound on separate small strips of core material and positioned in a gimballed fixture for use as an electronic compass. The sensing coils in each sensor sense only the components of magnetic field in that plane with one output being representative of the field along the axis of one of the coils and the other being representative of the field along the axis of the other coil. A secondary winding cooperating with each of these coils provides an output signal which is operated upon to remove any DC components and provide a signal indicative in waveshape of the flux in the core. Opposite polarity peak detectors are then used to determine the relative peak voltages with respect to ground for the purpose of determining the DC component which had been removed. The DC component is indicative of any external fields affecting the flux levels in the core material.

Abstract: A rod of magnetic material which has a very small diameter compared to its length is used in combination with a drive and output winding wound around the circumference of the core rod to provide the sensor for measuring magnetic field strength. The rod is periodically and cyclically driven to saturation in each direction by a triangular waveform drive signal generator. A point on the saturation curve in each direction of saturation is picked and the relative time between these points for a no external field condition is determined. Any deviation from this no external field condition is sensed and applied to an integrator which provides both the output signal and a feedback signal which is used in combination with the signal generator to compensate for effects of the external field on the saturation points in the sensor. When the output signal is representative of the magnetic field, there is again no deviation in the time of occurrence of saturation in the rod from the no external field condition.

Abstract: A magnetic field sensing device comprising a magnetic rod which is direction sensitive relative to the field being measured. The rod is of such design that the magnitude or the strength of the field being sensed, significantly affects the magnitude of the excitation field required to produce a saturation of the magnetic core. An external field in the longitude direction of the core will require that the excitation field magnitude required to produce a given level of saturation will be different in one direction than in the other, by magnitude equal to twice the component of the external field acting upon the core. The excitation field is produced by current in the winding with the current changing at a given rate so that the induced or output voltage is greater than a specified value; as long as the core permeability is greater than a given specified value.

Abstract: A magnetic field directional magnetic sensor wherein the magnetic material has a large length-to-diameter ratio and comprises two coils wound around the magnetic material which also have a small diameter compared to the length. A first coil is driven with a triangular waveform signal. After each occurrence of saturation, a voltage will be produced by the output coil. The voltage amplitude of the drive signal can be measured upon the occurrence of each of the output pulses from the second coil with the measuring or detection of the drive signal being used in a sample and hold circuit which averages the detected values for a determination of magnetic field being sensed in the longitudinal or long direction of the magnetic sensor.

Abstract: A flux gate unit for producing an output representing the directional orientation of the unit with respect to the horizontal component of the earth's magnetic field, and in which a saturable flux gate magnetic core structure is mounted for leveling movement relative to associated flux gate coil means, in a manner enabling maintenance of the core structure substantially continuously in level condition while avoiding the necessity for leveling movement of the flux gate coils, and thereby avoiding the necessity for connection of electrical leads to a movable part.