Abstract: A SQUID bias current adjustment device supplies a sinusoidal current at 40 kHz, for example, to a coil to generate magnetic field at a SQUID. The amplitude of the field corresponds to a half period of a field-voltage characteristic. Voltage generated from the SQUID at this time is filtered by using a filter to pick out components of 40 kHz and 80 kHz. The picked out signal components are rectified and converted to direct current, and the bias current is adjusted such that the maximum value is obtained. In this way, a SQUID bias current adjustment device can be provided capable of automatically adjusting bias current properly in a short period of time.

Abstract: First to third exciting coils are arranged at a reference position. First to third detecting coils are arranged at a measuring subject position distant from the reference position. Voltages induced in the first to third detecting coils are measured when the first exciting coil is excited. Voltages induced in the first to third detecting coils are measured when the second exciting coil is excited. Voltages induced in the first to third detecting coils are measured when the third exciting coil is excited. An azimuth of the measuring subject position from the reference position based on a predetermined calculation by using all nine induced-voltages which are obtained by the first to third detecting coils.

Abstract: In order to simplify the installation of an angle-of-rotation sensor and to prevent destruction or function impairment caused by temperature variations, a stamped lead assembly (25) is at least partially embedded into a shaped holding bracket (24) forming a holder unit (23) which holds a stator unit (2), a sensor element (4, 5) and an output unit (26, 51). An expansion unit (30) is positioned on the lead lines of the stamped lead assembly (25) and at least partially positioned in the shaped holding bracket (24). The expansion unit (30) consists of lead lines exposed through a window of the shaped holding bracket (24). The window is limited by at least one shaped holder strip. At least one expansion notch is incorporated into the lead lines.

Abstract: To provide device capable of enhancing the detection accuracy of a wheel speed detecting device and reducing cost. A wheel speed detecting device for a rear wheel includes a pulsar ring mounted on a rear wheel hub, and a pulse counting sensor mounted on a swing arm. The pulsar ring includes a disc, and pulse detecting holes are formed at a predetermined pitch on a pitch circle drawn at a radially inward circumferential position spaced at a predetermined distance from the outer edge of the disc. The pulse detecting hole is formed in a position on the center side apart from the outer edge of the pulsar ring, leaving the outer edge of the pulsar ring in a circular form. Therefore, it is possible to prevent warpage of the pulsar ring by the outer edge portion if the pulse detecting holes are made by pressing.

Abstract: A magnetic non-destructive method and an apparatus for measurement of cross sectional area of elongated ferrous objects such as steel wire ropes and for detecting local flaws is disclosed. A section of a wire rope is magnetized by longitudinally spaced magnetic poles. A magnetic field parameter, e.g. magnetic flux density, is measured in, by at least, one pair of points between the poles of magnetizing device (in an inter-pole area) at the object under test surface. The pair of points is formed by two sensors placed in the inter-pole area along a direct line parallel to the rope axis. The rope cross sectional area corresponds to a sum of the sensor pair signals. Local flaws, such as broken wires and pitting corrosion in the rope, is detected by a first differences of signals of the sensor pair.

Abstract: An encoder for a brushless motor of an Electric Power Steering (EPS) system that includes a commutation track coupled to a shaft for the generation of a commutation signal. The commutation signal in turn is used to generate an index signal every electrical cycle. The encoder further includes a set of high-resolution quadrature signal tracks. The set of high-resolution quadrature signal tracks generate a set of high-resolution signals which are phased at a set angular displacement with respect to one another. A set of sensors sense the commutation signal and the set of high resolution quadrature signals.

Abstract: A malfunction detector for magnetoresistive device sensors includes a window discriminator, a rotation indication circuit, and an alternative failure circuit. The window discriminator includes minimum and maximum voltage comparators, wherein if the sensor output signal is outside reference voltages, a first error signal is output. A rotation indication comparator outputs a square wave signal if the sensor output signal is detected. An alternative failure circuit includes a peak detector, a valley detector and a voltage comparator, wherein if a voltage differential between high and low values is less than a predetermined voltage differential, a second error signal is output.

Abstract: An inductive linear position sensor, particularly for use with motor vehicles has an oscillator circuit for creating a periodic alternating voltage signal, an exciting coil coupled to the oscillator circuit, a plurality of receiving coils with the exciting and receiving coils being structured as leads on a circuit board, evaluation circuitry for evaluating signals induced in the receiving coils and a movable inductive coupling element for influencing the strength of inductive coupling between the exciting coil and the receiving coils. The evaluation circuitry is arranged within the geometry of at least one of the sending (exciting) and receiving coils. Effective surface areas of the receiving coils are structured at beginning and end areas of the sensor such that, when there is no movable element present, a zero voltage results at the output taps of the receiving coils.

Abstract: The present invention is directed to a disc heater for use with a spin-stand. The disc heater is adapted to heat a disc that is mounted to a spindle of the spin-stand. The disc heater includes a heater support, a heater, and a controller. The heater support is couplable adjacent the spindle and the disc and is adapted to support the heater near a surface of the disc. The heater produces heat that raises at least a surface of the disc to a temperature that simulates an operating temperature of a disc drive. The controller is electrically coupled to the heater and controls the heat produced by the heater. The spin-stand is adapted to perform various tests on the transducing head. Additional tests, such as accelerated aging studies, can also be performed on the disc.

Abstract: A method for operating an eddy current sensor (10) with a measuring coil (2) and an evaluation circuit (4) for determining material or geometric parameters of a test object (5), in which the test object (5) is arranged at a distance (d) from the measuring coil (2). The impedance of the measuring coil (2) is evaluated, while the measuring coil (2) is being supplied with an alternating voltage of a predetermined frequency, and the evaluation circuit (4) determines the material and geometric parameters of the test object (5) based on the impedance of the measuring coil (2). The impedance of the measuring coil (2) is determined at an alternating voltage of a first frequency, and the impedance of the measuring coil (2) is determined at an alternating voltage of a second frequency, and the evaluation circuit (4) computes the material and geometric parameters of the test object (5) on the basis of the impedances of the measuring coil (2) at the first and the second frequencies.

Abstract: The invention relates to electrical engineering, in particular, to devices employed in a step magnetoelectric motor, and it is intended for generating the Sin and Cos of electric signals that uniquely determine an armature position relative to toothed structure of a stator. To increase the accuracy the sensor contains two composite U-shaped magnetic conductors, on pole cores of which the teeth are formed. The group coordinates difference of the teeth being equal to (&agr;±0,5) Z, where &agr; is an integer, Z is the teeth spacing and 0,5 represents the decimal notation of ½. A permanent magnet is connected in series with one of the constituents of U-shaped magnetic conductors, and the magnetic induction converters are placed in proximity to the pair of the like magnetic poles of the magnetic conductors.

Abstract: A compact and high-accuracy angular position measuring device is provided which has magnets installed in a rotor core and a magnetic sensor installed in a stator core. The magnetic sensor produces an output indicative of an angular position of the rotor core as a function of a change in density of magnetic flux produced by the magnets. The magnets are so arranged in the rotor core that the same poles are opposed magnetically to produce a repellent force in magnetic fields of the magnets, thereby causing the magnetic flux to go to the magnetic sensor through the rotor core. This eliminates the need for an air gap between the stator core and the poles of the magnets which is formed in a conventional device, thus allowing the device to be reduced in size and an error in output of the device to be decreased.

Abstract: Improved targets for use in DC magnetron sputtering of nickel or like ferromagnetic face-centered cubic (FCC) metals are included for forming metallization films having effective edge-to-edge deposition uniformity of 5% (3&sgr;) or better. Such targets may be characterized as having: (a) a homogeneous texture mix that is at least 20% of a <200> texture content and less than 50% of a <111> texture content, (b) an initial pass-through flux factor (% PTF) of about 30% or greater; and(c) a homogeneous grain size of about 200 &mgr;m or less.

Abstract: An eddy current inspection probe for inspecting a preselected surface at least partially defining an opening in a component. The probe includes a cast core having an exterior surface sized and shaped for receipt within the opening of the component and an eddy current array positioned over the exterior surface of the core for generating and detecting magnetic fields in the component to inspect the preselected surface of the component.

Abstract: Position measurement system of the relative position between two objects. The system comprises a first and a second inductive system. The first inductive system comprises a transmitting coil and a first detector, with the attribute that the pattern of conductors that form the coil extends along a longitudinal axis. A second inductive system comprises a second transmitting coil and a second detector, with the attribute that the coil extends essentially in the longitudinal direction. The second trasmitter coil can be realised as a Meander pattern of conductive material, with return path in its center-line. Using the detectors, it is possible to accurately determine the linear and/or angular position(s) of two bodies relative to each other.

Abstract: A position sensor system capable of self compensation over wide temperature ranges, air gaps and tilts. Three matched MRs are aligned in the direction of movement of a magnetic target. The middle MR is the position sensor, and the two outer MRs serve as reference sensors which sense the magnetic field at the limits of the position sensing range. The cooperating magnetic target assures that one of the two outer MR elements is always exposed to some maximum magnetic field, BMAX, corresponding to a position XMAX, and the other MR element is always exposed to some minimum magnetic field, BMIN, corresponding to a position XMIN, such that BMIN≦BX≦BMAX, corresponding to XMIN≦X≦XMAX, where BX is the magnetic field measured by the middle MR and varies with the position, X, of the target. The actual position, X, is computed assuming a linear relation between MR resistance in the magnetic field range from BMIN to BMAX and the position, X, of the target.

Abstract: A replaceable probe tip holder for an associated low capacitance probe head has a cap with a series of cavities formed therein and a bore extending from the inter most cavity to the front end of the cap. A first cavity receives the probe head tubular housing, a second cavity receives a portion of the probe head substrate extending from the housing, and a third cavity receives a first resilient compression member and a first electrically conductive probing tip having a shank and a head. The head is disposed in the third cavity in contact with the first resilient compression member and shank extends through the bore with the end of the shank extending from the front end of the cap. Attachment arms extend from the back end of the cap and are positionable on the outside of the housing. The replaceable probe tip holder may also be configured with differential probing tips having two electrically conductive probing tips extending from the cap.

Abstract: A rotation angle sensor including a magnet rotatable about an axis, a first and second yokes arranged around said magnet and diametrically opposed to each other, and a Hall effect device disposed between the first and second yokes. The yokes include arcuately curved pole piece portions radially opposed to the magnet and overhang portions extending angularly inwardly from the pole piece portions across the axis of the magnet, respectively. The overhang portions have a generally sector shape and cooperate to define a gap therebetween within which the Hall effect device is disposed. Leakage flux reducing members circumferentially extends between the pole piece portions.

Abstract: A method and apparatus for the contactless determination of planarity and a ferromagnetic metal strip during transit of the strip through a strip-processing line or cold-rolling line. Hysteresis loops repetitively impressed in the metal strip and the tangential magnetic field strength is measured at a surface thereof and electromagnetic parameters are determined from the time course of the tangential field strength signal. The parameters are functions of the mechanical stress which is evaluated to determine residual intrinsic stress distribution and then the planarity or nonplanarity of the strip.

Abstract: A non-contact linear position center has juxtaposed transmit and receive sections with a coupler or slider section interposed therebetween carrying a symmetrical attenuating conductive pattern. The inductive coupling of coils on the transmitter and receive sections is attenuated in accordance with the linear position of the pattern on the coupler. A unique sinusoidal signal is generated whose phase is indicative of the linear position of the coupler.