Abstract: Provided herein are systems and methods which use the solenoid itself to sense the position of the armature within the solenoid, and therefore to determine the position of the solenoid's armature, and or any related devices whose movement is dependent on the armature's movement. Specifically, a system in which the change in self-induction that occurs when the armature moves relative to the solenoid coil is used to detect the location of the armature.

Abstract: A magnetic field response sensor comprises an inductor placed at a fixed separation distance from a conductive surface to address the low RF transmissivity of conductive surfaces. The minimum distance for separation is determined by the sensor response. The inductor should be separated from the conductive surface so that the response amplitude exceeds noise level by a recommended 10 dB. An embodiment for closed cavity measurements comprises a capacitor internal to said cavity and an inductor mounted external to the cavity and at a fixed distance from the cavity's wall. An additional embodiment includes a closed cavity configuration wherein multiple sensors and corresponding antenna are positioned inside the cavity, with the antenna and inductors maintained at a fixed distance from the cavity's wall.

Abstract: Sensor assemblies including transmitter and receiver antennas to respectively transmit or receive electromagnetic energy. The sensor assemblies are disposed in downhole tools adapted for subsurface disposal. The receiver is disposed at a distance less than six inches (15 cm) from the transmitter on the sensor body. The sensor transmitter or receiver includes an antenna with its axis tilted with respect to the axis of the downhole tool. A sensor includes a tri-axial system of antennas. Another sensor includes a cross-dipole antenna system.

Abstract: A well logging instruments includes an electrically conductive sonde mandrel. At least one electrical sensor is affixed to an exterior of the mandrel. The sensor is configured to be attached to the mandrel by sliding along an exterior surface thereof. A pressure-sealing electrical feedthrough bulkhead makes electrical connection from the at least one sensor through a wall of the mandrel.

Abstract: A magnetic sensor assembly (S) of the type having at least one capacitor (44) electrically connecting an output signal (70) from a magnetic sensor unit (24) to an output signal source (30) includes switch (14) for controllably electrically disconnecting the capacitor (44) from output signal (70) and alternatively connecting the capacitor (44). The capacitor (44) is disconnected from the magnetic sensor unit (24) by the switch (14) during times that transient signals may be generated by the magnetic sensor unit (24) thereby preventing the capacitor (44) from being charged. A magnetic sensor assembly (100) uses printed circuit boards (PCB) (102) having a conductive element (106) on or within the PCB (102) beneath a magnetic sensor element (104) for testing.

Abstract: A position-sensing system magnetically senses the position of a piston rod moving with respect to a cylinder. A magnetically hard layer on the piston rod provides a recording medium. Information is perpendicularly magnetized in regions of the magnetically hard layer. These regions provide an encoding scheme for determining the position of the piston rod. Magnetic-field sensors are positioned over redundant tracks of magnetically recorded regions. Each magnetic-field sensor positioned over a given track senses the same magnetized regions while the piston rod moves with respect to the cylinder. Other magnetic-field sensors can sense ambient fields for use in performing common-mode rejection. A write head can dynamically repair damaged or erased regions detected by the magnetic-field sensors. Energized by a battery-backup power source, the magnetic-field sensors and associated circuitry can continue to track movement of the piston rod when the machinery is off.

Abstract: A sensor assembly for measuring a linear position includes a slider having a rack gear that engages a pinion gear. The pinion gear is rotatable relative to the slider responsive to linear movement. The pinion gear supports a permanent magnet that generates a magnetic field. Changes in the magnetic field caused by rotation of the pinion gear are sensed by a magnetic field sensor. Signals from the magnetic field sensor are indicative of a rotation of pinion gear and correspond to linear movement of the slider.

Abstract: Described is a piston rod position-sensing system having a cylinder and piston rod arranged in the cylinder for movement with respect thereto. A magnetically hard layer is formed on the piston rod to provide a recording medium. The magnetically hard layer is made of a cobalt-phosphorous (Co—P)-based alloy. A magnetic pattern is recorded in the magnetically hard layer. A magnetic field sensor located in the cylinder senses the recorded magnetic pattern while the piston rod is moving with respect to the cylinder.

Abstract: A fluxgate sensor includes a magnetic core including CoNbZr, an excitation coil, and a magnetic field sensing coil. The fluxgate sensor can use CoNbZr. A low coercivity and high magnetic permeability can be obtained.

Abstract: An induction or propagation apparatus for performing measuring the tensor resistivity of a sample of matter includes a non-conductive, generally cylindrical tubular member adapted to receive the matter therein, a triaxial transmitter, at least one triaxial receiver, and an electronic module. The electronic module is adapted to energize the triaxial transmitter, control acquisition of signals by the at least one triaxial receiver, and perform anisotropic measurements and analysis. The triaxial transmitter and the at least one triaxial receiver are disposed on the generally cylindrical tubular member in axial spaced relationship.

Abstract: An eddy current acquisition system integrates traditional elements of a nuclear steam generator tubing inspection into a single modular system comprising three subsystems: the take-up reel subsystem, the acquisition instrument, which is located in the hub of the take-up reel, and the pusher head subsystem. All of the control electronics are respectively enclosed in bases of the pusher head and the take-up reel subsystems in water-resistant and dust proof enclosures. Simplified setup is achieved by employing a single communication bus linking an identification (“ID”) chip in each component to a host computer. The ID chip stores and reports product part numbers, descriptions and serial numbers and revision or upgrade status and may also store statistical information such as device duty cycles, performance statistics, repair history, and the like.

Abstract: Planishing or stress relief in a welded joint (34) is accomplished with a hammer (12) and a backing bar (26). The hammer is applied on a first side (1) to a first surface (31) of the structure (30). To indicate the proper position of the backing bar, a first magnet (20; 320) is associated with the hammer, and a magnetic sensor arrangement (24; 224; 300) is located on the other side (2) of the structure. In one embodiment, the sensor arrangement is a second magnet (24) which is held in place by the magnetic field (40) of the first magnet. In a second embodiment, the sensor includes a line array (262) of individual sensors, each associated with an indicator of a line array (264) of indicators. In a third embodiment, the sensor includes a line array (300) of two magnetic sensors, which are coupled to a differential indicator (324).

Abstract: An electronic device, such as mobile terminal devices, with a photographing function, and in the case where a photographing target is a person, enhances its function for protecting the photographing target from being photographed without consent by such as spy shots.

Abstract: The present invention provides a current sensor of smaller and simpler configuration, capable of measuring a current to be detected with high precision and stability. A magnetic sensor includes: an element substrate including a magnetoresistive element, the magnetoresistive element having a pinned layer with a magnetization pinned to a direction, an intermediate layer, and a free layer whose magnetization direction changes according to an external magnetic field; and a magnetic sheet attached on one side of the element substrate so as to apply a bias magnetic field to the magnetoresistive element.

Abstract: A sensor measures the interaction of an applied magnetic field to a sample surface that includes magnetic materials to determine whether the samples surface has been corroded. The sensor measures the magnetic force resulting from the interaction or the magnetic flux density to determine the content of magnetic material in localized regions of the sample surface. The sensor includes a cantilever beam with a strain gauge for measuring magnetic force. Alternatively, the sensor includes a magnetic flux density sensor to measure magnetic flux density.

Abstract: Systems and methods according to exemplary embodiments address, among other features, the area of calibrating a sensor using a constant vector field. In one exemplary embodiment, a method for calibrating a sensor includes the steps of placing the sensor in a cube, rotating the cube between a plurality of different orientations, collecting at least one reading from the sensor from each of the plurality of different orientations and calibrating the sensor using the collected readings.

Abstract: A detector for measuring relative position along a measurement path comprising: a passive, laminar electrical intermediate device extending along the measurement path wherein the extent of the said electrical intermediate device in an axis normal to the measurement path varies along the measurement axis; at least one laminar transmit winding and at least two laminar receive windings wherein the said at least two laminar receive windings are displaced from each other along the measurement path wherein each laminar receive winding is substantially electrically balanced with respect to the at least one laminar transmit winding; arranged such that the mutual inductance between at least one laminar transmit winding and at least two laminar receive windings indicates the relative position of the electrical intermediate device.

Abstract: An apparatus and method for testing a component of a magnetic disk drive in which one or more drive-based components is used in the testing process. Each of the drive-based components is based on a corresponding one of the components of the magnetic disk drive. During testing, the component to be tested and at least one of the drive-based components are selectively engaged.

Abstract: A sensor for detecting surface defects of a metal tube solves a problem of a conventional eddy current probe in that it is difficult to detect a crack in the circumferential direction of a metal tube. The sensor includes a plurality of coils wound at a predetermined inclined angle. The plurality of coils is inserted into the inside of a metal tube. Alternating current is applied to the coils to measure a change in impedance of the coils due to a change in an eddy current generated in the metal tube, thus detecting a surface defect of the metal tube.

Abstract: The invention relates to a SQUID arrangement for measuring a change in a magnetic field, the change in the magnetic field being caused by a specimen that is arranged in a magnetization field and the SQUID arrangement including a direct current SQUID. In order to provide a simple design in which the losses in the magnetic flux are also simultaneously minimized, it is provided that the SQUID itself is embodied for generating the magnetization field.