Abstract: A monitoring system including rubber magnets 41 to 44 provided inside of a belt 1, and magnetic sensors 51 and 52 provided outside of the belt 1, and magnetic forces generated by the rubber magnets 41 to 44 are detected by the magnetic sensors 51 and 52, thereby detecting a condition of the belt 1, wherein the magnetic sensors 51 and 52 are configured using MI sensors.

Abstract: A method is disclosed for characterizing a local magnetic field, in particular a stray field caused by a magnetizable or magnetic particle in a prescribed measuring area of a magnetic field. In at least one embodiment, a sensor array including a number of magnetic sensors and each having at least one layer sensitive to magnetic fields is arranged at least in a subregion of the measuring area, and at least one device is provided for reading out separately the signal from each sensor. According to at least one embodiment, the size, in particular of XMR sensors and the surface of the layer sensitive to magnetic fields and the grid dimension of the sensor array, are selected such that at least two neighboring sensors are influenced by the local stray field. An associated device for carrying out the method is also disclosed.

Abstract: A method of non-destructively testing a magnetisable conducting object surrounded by a magnetisable layer wherein the field strength of a primary magnetic field that is applied exterior to the magnetisable layer is abruptly changed. A vanishing secondary magnetic field generated by eddy currents induced by the changed field strength of the primary magnetic field is received and the temporal field strength of the received secondary magnetic field is analysed for deriving characteristics of the magnetisable conducting object. Furthermore, a transient tertiary magnetic field exterior to the magnetisable layer when the field strength of the primary magnetic field abruptly changes is applied wherein the orientation of the primary and tertiary magnetic field, respectively, are mutually opposite.

Abstract: A measuring device for detecting a metal object includes an emission coil configured to produce a magnetic field and a compensation network which is connected to the emission coil. A differential voltage is applied between the emission coil and the compensation network. The measuring device also includes a control device configured to supply the emission coil and the compensation network with alternating voltages such that the value of an alternating voltage component of the differential voltage, which is time synchronized with the alternating voltage, is minimized. The control device is configured to detect the metal object when a ratio of the alternating voltages does not correspond to a ratio of the flows flowing through the emission coils and the compensation network.

Abstract: In an embodiment, an oxygen sensor comprises a giant magnetoresistance device (10), and a magnetic field generator (14, 14a, 14b) arranged to generate a magnetic field (12, 12a, 12b) overlapping the giant magnetoresistance device and an examination region (20). A component (Bx) of the magnetic field detected by the giant magnetoresistance device is dependent upon an oxygen concentration in the examination region. In an embodiment, a chip (40) includes one or more electrically conductive traces (14a, 14b) disposed on or in the chip and a giant magnetoresistance device (10) disposed on or in the chip such that electrical current flowing in the trace or traces generates a magnetic field (12a, 12b) that overlaps the magnetic field sensor, said magnetic field being perturbed (Bx) by ambient oxygen (24) such that a signal output by the magnetic field sensor indicates ambient oxygen concentration.

Abstract: A system and method for measuring volumes and areas using electromagnetic induction techniques. A current is generated and fed into one of two coil assemblies to induce voltage into another coil assembly to provide accurate values for volume or area.

Abstract: Provided is a magnetic sensor device capable of suppressing a variation in determination for detection or canceling of a magnetic field intensity, which is caused by noise generated from respective constituent elements included in the magnetic sensor device and external noise, to thereby achieve high-precision magnetic reading. The magnetic sensor device includes: a first D-type flip-flop and a second D-type flip-flop each having an input terminal connected to an output terminal of a comparator; an XOR circuit having a first input terminal and a second input terminal which are connected to an output terminal of the first D-type flip-flop and an output terminal of the second D-type flip-flop, respectively; a selector circuit; and a third D-type flip-flop having an input terminal connected to an output terminal of the selector circuit.

Abstract: In an embodiment, a method of characterizing a polycrystalline diamond compact is disclosed. The method includes providing the polycrystalline diamond compact, and measuring at least one magnetic characteristic of a component of the polycrystalline diamond compact.

Abstract: According to the present invention, a method for determining coercivity of a coercivity distribution magnet, whereby coercivity of each portion in the coercivity distribution magnet can be determined with good accuracy without, for example, cutting the coercivity distribution magnet into pieces and thus quality assurance can be achieved with good accuracy, is provided.

Abstract: A storage medium having a low frequency time-domain signal stored thereon, and methods of generating, scoring, testing and using the signals are disclosed. In one general embodiment, the signal is derived from a taxane-like compound or an siRNA against human GADPH, and is useful in treating cancer in a subject by exposing the subject a low-magnetic field transduction of the signal. Also disclosed are improved signal transduction methods.

Abstract: The present invention provides apparatus for scanning a product to detect metal in that product. The apparatus comprises a drive coil (4), for generating an electromagnetic field in the product, and a detection coil arranged to detect fluctuations in the magnetic field caused by the presence of a metallic particle in the product. A drive circuit (26) for the drive coil (4) comprises a plurality of switches (19 to 22) driven by a controller (16), which switch alternately connect the drive coil across a potential difference to cause the drive coil to be driven at an operating frequency determined by operation of the switches. Using a switching circuit to drive the drive coil (4) greatly increases the number of frequencies at which the drive coil may be operated. The invention has particular application to the food industry.

Abstract: In an embodiment, a method of characterizing a polycrystalline diamond element is disclosed. The method includes providing the polycrystalline diamond element, and measuring at least one magnetic characteristic of the polycrystalline diamond element.

Abstract: Methods and apparatus for non-intrusive power monitoring and current measurement in a circuit breaker without modification of the breaker panel or the circuit breaker itself. In one example, an inductive pickup sensor senses current from the breaker face, an inductive link transmits power through a steel breaker panel door, and a passive balanced JFET modulator circuit modulates a carrier signal on the inductive link with information regarding the sensed current. A demodulated breaker current signal is available outside of the breaker panel door. The JFET modulator circuit does not require DC power to modulate the carrier signal with the information regarding the sensed current from the breaker. Such methods and apparatus may be interfaced with a spectral envelope load detection system that can monitor multiple loads from a central location.

Abstract: The invention relates to a method of analyzing a plurality of ferromagnetic particles (1). The method comprises the following steps: a) aligning the particles (1) of this plurality in such a manner that each of the particles is oriented substantially in the same direction; b) fixing the particles (1) of said plurality in the alignment; c) exposing the internal regions of the particles (1) as aligned in this way; d) determining the nature of each of the particles and grouping the particles by category as a function of their natures; and e) in each category, determining the metallurgical structure and the chemical composition of one or more of the particles.

Abstract: A system includes a magnetoresistive (MR) bridge circuit, a magnetic field sensor, and an adjustable load. The MR bridge circuit receives a supply voltage and generates an output voltage that indicates a strength/direction of a magnetic field. The MR bridge circuit includes first and second MR elements connected in series between a supply node and a ground node, and third and fourth MR elements connected in series between the supply node and the ground node. The output voltage is generated between a first node that is common to the first and second MR elements and a second node that is common to the third and fourth MR elements. The sensor generates signals based on the strength/direction of the magnetic field. The adjustable load is connected in parallel with one of the MR elements, and has a resistance that is controlled based on the signals generated by the sensor.

Abstract: Provided is a stud finder for determining the location of a stud within a wall. The stud finder includes a body having an internal compartment formed therein which is sized and configured to house a magnetic element therein. The stud finder is moveable along the wall to place the magnetic element in magnetic attraction with metallic fasteners (i.e., nails, screws, etc) disposed within the stud, such as for securing drywall to the stud. The magnetic attraction urges the magnetic element toward the metallic element to provide a visual indication as to the precise location of the metallic element, as well as the underlying stud.

Abstract: The invention relates to a method and associated apparatuses (100) for the detection of magnetic particles (MP) in a sample chamber (111). The method comprises the determination of a “particle-parameter” that is related to the amount of magnetic particles (MP) in a first detection region (P, C), the determination of a “cluster-parameter” that is related to the degree of clustering of magnetic particles (MP) in a second detection region (P, C), and the evaluation of the particle-parameter based on the cluster-parameter. Various apparatuses are disclosed that can be applied in said method. In one apparatus (100), a magnetic field (B) is generated in the sample chamber (111) in such a way that it has different inclinations in a first and second field region (P, C) and/or that it is oblique to the binding surface (112) in at least one field region.

Abstract: A Hall-Effect measure apparatus comprises a magnetic source, a wafer on a thermal chuck, a dc current source and a voltage meter. The magnetic source generates a magnetic field in a perpendicular position relative to the wafer. Furthermore, the magnetic field is targeted at a specific region of the wafer to be tested. By performing a Hall-Effect measurement and van der Pauw measurement, the carrier mobility of the specific region of the wafer can be calculated.

Abstract: A balanced bridge variable-reluctance sensor with no internal circuit components, springs, or dielectric for performing vibration analysis in high-vibration, high-temperature, and other extreme environments. The present invention includes a variable-reluctance sensor in a vibration-sensing capacity. The present invention has inherently high reliability due to its simplicity. The sensor is solidly mounted to a structure that is being monitored and allows a vibration wave to pass through a floating sensor bridge. The sensor vibrates at the same frequency as the application being measured.

Abstract: An eddy current probe for inspecting steam generator tubing, that has radially outwardly biased rollers that function to center the probe within the tubing and reduce friction as the probe moves along the interior of the steam generator heat exchanger tube walls. The rollers may include a braking system which controls the drag on the rollers and thus the speed of the probe along the tubing. The direction of travel of the rollers is remotely adjustable to control the inspection pattern and the force of the rollers against the interior surface of the tubing can be remotely controlled.

Abstract: The present invention relates to a measuring device including a sensor catheter, an evaluation unit, and means for receiving a magnetic field and converting the magnetic field to an electrical measurement signal which are situated in the sensor catheter and connected to the evaluation unit. The evaluation unit is designed to evaluate the electrical measurement signal.

Abstract: A conductivity sensor is disclosed. The conductivity sensor includes an oscillator for providing an input signal and a reactive circuit having an induction coil, a capacitive element, and a resistive element connected in parallel. The induction coil is adapted to be placed adjacent to a specimen. The conductivity sensor further includes a control circuit for driving the reactive circuit to resonance when the induction coil is placed adjacent to the specimen. The reactive coil is configured to provide an output signal having a parameter representative of the conductivity of the specimen when the reactive circuit is at resonance. The induction coil may include a first conductive element that spirals outward to an external perimeter and a second conductive element operably connected to the first conductive element. The second conductive element spirals inward from the external perimeter staggered relative to the first conductive element.

Abstract: According to one aspect, an integrated magnetic particle measurement device for detecting a presence or absence of magnetic particles in a sample volume includes at least one sensor cell having a differential sensor pair. An active sensor oscillator frequency is responsive to one or more magnetic particles situated within a sample volume. The sensor cell is configured to be operative in the absence of an externally applied magnetic field. A frequency measurement circuit provides as a time-multiplexed output a first count representative of the active sensor oscillator frequency and a second count representative of the reference sensor oscillator frequency. A calculated difference between the first count and the second count is indicative of a presence or an absence of one or more magnetic particles within the sample volume. An integrated magnetic particle measurement system array and a method for detecting one or more magnetic particles are also described.

Abstract: A method of non-destructive testing that employs composite systems that include a curable resin and detectable particles that have a property that can be distinguished from a property of the resin is disclosed. Array probes useful in the method also are disclosed.

Abstract: An arrangement and a method for influencing and/or detecting magnetic particles in a region of action is disclosed, which arrangement comprises: —selection means for generating a magnetic selection field having a pattern in space of its magnetic field strength such that a first sub-zone having a low magnetic field strength and a second sub-zone having a higher magnetic field strength are formed in the region of action, —drive means for changing the position in space of the two sub-zones in the region of action by means of a magnetic drive field so that the magnetization of the magnetic particles changes locally, —receiving means for acquiring signals, which signals depend on the magnetization in the region of action, which magnetization is influenced by the change in the position in space of the first and second sub-zone, wherein the selection means and/or the drive means and/or the receiving means comprises at least partially a litz wire/stranded wire.

Abstract: The present invention is directed to a system and a method for inspecting a subsea pipeline. The method comprises the steps: detecting a defect along the subsea pipeline using a subsea magnetometric tomography method (MTM) module adjacent the subsea pipeline; and determining a position of the subsea MTM module, thereby determining the position of the defect. The method further comprises determining the position of the subsea MTM module relative to a surface vessel; and determining an absolute position of the surface vessel.

Abstract: A method of testing for defects in the bottom of an above ground storage tank, the tank bottom having a lip extending outwardly from the tank wall around the circumference of the tank. A special magnetostrictive sensor is designed to be placed on this lip. The sensor is placed over a strip of magnetostrictive material, which generally conforms in length and width to the bottom of the probe, with a couplant being applied between the strip and the lip surface. The sensor is then operated in pulse echo mode to receive signals from defects in the bottom of the tank. It is incrementally moved around the circumference of the tank.

Abstract: In a method for determining geometrical characteristics (d) of an anomaly (12) which changes the electrical conductivity in the region near the surface of an electrically conducting, in particular a metallic test object (10), a considerable simplification is achieved in that, in the region of the anomaly (12) in the test object (10), eddy currents (13, 14) of different frequencies are excited, and the magnetic field (By,0), which is produced by the excited eddy currents, is scanned in the vicinity of the anomaly (12) and the geometric characteristics of the anomaly are exclusively deduced from the distribution of the magnetic field (By,0).

Abstract: A magnetic field generator includes a substrate, a main generator coil, at least one field sensor, at least one shim coil, a driver circuit and a correction circuit. The main generator coil, the field sensor, and the shim coil are all disposed on the substrate. The driver circuit is coupled to drive the main generator coil with a driving current at a selected frequency. The correction circuit is coupled to receive a signal at the selected frequency from the at least one field sensor and, in response to deviations in the signal from a predefined baseline, to drive the at least one shim coil with a driving current having an amplitude configured to return the signal to the baseline.

Abstract: A method for influencing and/or detecting magnetic particles in a region of action, magnetic particles and the use of magnetic particles is disclosed, which method comprises the steps of: —introducing magnetic particles into a region of action, —generating a magnetic selection field having a pattern in space of its magnetic field strength such that a first sub-zone having a low magnetic field strength and a second sub-zone having a higher magnetic field strength are formed in the region of action —changing the position in space of the two sub-zones in the region of action by means of a magnetic drive field so that the magnetization of the magnetic particles change locally, —acquiring signals, which signals depend on the magnetization in the region of action, which magnetization is influenced by the change in the position in space of the first and second sub-zone, wherein the magnetic particles comprise a core region and a shell region, the core region comprising a magnetic material, wherein the magnetic mater

Abstract: A segmented magnetostrictive patch array transducer capable of generating a high frequency shear wave in a structure such as a rod or a pipe, a structural fault diagnosing apparatus including the segmented magnetostrictive patch array transducer, and a method of operating the segmented magnetostrictive patch array transducer are shown. The segmented magnetostrictive patch array transducer includes a plurality of magnetostrictive patches attached along a circumference of a rod member; a plurality of insulators that are disposed on the magnetostrictive patches; a plurality of meander coils, each of the meander coils comprising a plurality of coil lines extending along the circumference direction of the rod member on each of the insulators, wherein a current flows through adjacent coil lines in opposite directions to one another; and a plurality of magnets that respectively form a magnetic field along the circumferential direction of the rod member on the magnetostrictive patches.

Abstract: A system and a method for determining the torque imposed on a filament, such as a single DNA strand or macromolecule, using a magnetic probe and an imaging device.

Abstract: Methods and apparatus for non-intrusive power monitoring and current measurement in a circuit breaker without modification of the breaker panel or the circuit breaker itself. In one example, an inductive pickup sensor senses current from the breaker face, an inductive link transmits power through a steel breaker panel door, and a passive balanced JFET modulator circuit modulates a carrier signal on the inductive link with information regarding the sensed current. A demodulated breaker current signal is available outside of the breaker panel door. The JFET modulator circuit does not require DC power to modulate the carrier signal with the information regarding the sensed current from the breaker. Such methods and apparatus may be interfaced with a spectral envelope load detection system that can monitor multiple loads from a central location.

Abstract: This method for detecting a magnetic disturber method comprises: the measurement (52) of the magnetic field emitted by the emitter by at least two triaxial sensors placed at different known positions, for each sensor, the determining, (54) from the magnetic field measured by this sensor, of the coordinates of a direction vector collinear with an axis passing through the geometrical center of the emitter and the geometrical center of this sensor, the geometrical center of the emitter being the point at which there is located a magnetic field point source which models this emitter and the sensor being capable of being modeled by a point transducer situated at a point where the magnetic field is measured and constituting the geometrical center of this sensor, verification (56;70) that the smallest distance between the axes, each collinear each with one of the direction vectors, is smaller than a predetermined limit, and if this is not the case, the reporting (64) of the presence of a magnetic disturber and, i

Abstract: The surface length of a metal subject to be inspected is evaluated by detecting an eddy current without using a combination of a scale and visual or liquid penetrant inspection. An exciting coil and a detecting coil are scanned above the subject in a length direction. An eddy current detector measures an output voltage corresponding to scanning positions based on an output from the detecting coil. Based on an output voltage distribution curve indicating a distribution of output voltages corresponding to the scanning positions, position information is extracted corresponding to values which are within a differential voltage range and lower by 12 dB than a maximum value of the output voltages on the left and right sides of the distribution. A distance between the positions included in the extracted information is calculated to evaluate the length of a slit which is a defect present on the subject surface.

Abstract: A belt monitoring system which can accurately monitor the condition of a conveyor belt by correcting it for the effect of belt deviation. Wear detecting magnets (11), which are rubber magnets spanning the entire belt width, are embedded at intervals along the circumferential direction of the conveyor belt (2). Also, position determining magnets (12, 12z) are embedded in positions a predetermined distance apart from the wear detecting magnets (11). In addition, a plurality of magnetic field detecting means (13: 13A-13G) for detecting the magnetic fields from the magnets (11, 12, 12z), which are arranged at predetermined intervals in the width direction of the conveyor belt (2), are disposed in a position spaced apart from the surface of the conveyor belt (2).

Abstract: There is provided a nondestructive inspection apparatus using a SQUID magnetic sensor which allows nondestructive and accurate detection of magnetic particles in an insulator such as an electronic device or in a magnetizable member. The nondestructive inspection apparatus using the SQUID magnetic sensor comprises: a magnet for horizontal magnetization 4, the magnet applying a magnetic field to a specimen in the longitudinal direction of the specimen 3?; an inspection unit on which a specimen 3 is set, the specimen 3 being horizontally magnetized in the longitudinal direction by the magnet for horizontal magnetization 4; and belt conveyers 2, 5 for conveying the horizontally magnetized specimen 3; and a gradiometer 8 for detecting a particle horizontally magnetized along with a magnetizable member as the horizontally magnetized specimen 3.

Abstract: A rubber magnet (3) includes a plate-like diagonal portion (21) and a plate-like parallel portion (22) which are both magnetized in a thickness direction, the diagonal portion (21) extending in a conveyor belt width direction while linearly extending, in section in a conveyor belt length direction, from an outer side end (3b), which is closer to the front-side surface (2a), to an inner side end (3a), which is away from the front-side surface (2a), while being at an angle to the front-side surface (2a), the parallel portion (22) being formed continuously from the inner side end (3a) of the diagonal portion, so as to be arranged parallel to the front-side surface (2a).

Abstract: A pipeline inspection tool includes two pole magnets oriented at an oblique angle relative to the central longitudinal axis of the tool body. An array of sensor coil sets is located between opposing edges of the two pole magnets and oriented perpendicular to the central longitudinal axis. Each sensor coil set includes a transmitter coil and two opposing pairs of receiver coils that are gated to receive reflections from the wall of a tubular member. Because the line of sensor coils is rotated relative to the magnetic bias field, the receiver coils are in-line with, and have the same angular orientation as, the transmitter coil. The tool provides improved sensitivity to small defects, substantial decrease in RF pulser power requirements, full circumferential coverage, self-calibration of the transmitted signals, and less interference between transmitter coils caused by acoustic ring around.

Abstract: A magnetic detection apparatus comprises: a magnetic detection section which is obtained by pressing a base including a magnetic detection device, and magnetic field generation means fixed to the base, into a cap so as to integrate the base, the magnetic field generation means, and the cap; and a secondary molding section including an attachment section for attaching the magnetic detection section, and a connector section for extracting a signal detected by the magnetic detection section.

Abstract: A method for sensing a microwave magnetic field polarization component of a microwave field generated by a microwave device, comprises the steps of generating a static magnetic field having a predetermined amplitude and a predetermined direction relative to the microwave magnetic field polarization component to be sensed, preparing an atom cloud of ultracold probe atoms in defined hyperfine levels, wherein the hyperfine levels of the probe atoms are split in transition frequencies by the static magnetic field, applying a microwave pulse including the microwave magnetic field polarization component to be sensed to the atom cloud, wherein a spatial state distribution of the probe atoms is created by Rabi oscillations during the microwave pulse between the hyperfine levels of the probe atoms being resonant with the microwave magnetic field polarization component, and collecting a state image of the probe atoms, said state image depending on the spatial state distribution of the probe atoms and representing the m

Abstract: A magnetostrictive transducer that generates a large shear horizontal (SH) wave useful for non-destructive testing of a plate member, and method and apparatus for structural health monitoring by using the magnetostrictive transducer. The magnetostrictive transducer includes: a magnetostrictive patch array comprising a plurality of magnetostrictive patches that have different radii of curvature, and have the same center of curvature when arranged on a plate member and form an overall fan-shape; a static magnetic field forming unit comprising two magnets that are respectively installed on both sides of the magnetostrictive patch so that a magnetic field is formed in parallel to an arc direction of the magnetostrictive patch; and a dynamic magnetic field forming unit comprising a wound coil comprising a plurality of curved portions.

Abstract: An electromagnetic detection system comprising: a transmitter loop for generating a primary magnetic field, and spaced apart receiver coils for measuring a secondary magnetic field generated in response to the primary magnetic field.

Abstract: Disclosed is a method of analysing a magnetic material which includes the construction of a signature S(H) of the magnetic material formed from at least two points S(H)P, this construction including obtaining the value of each point S(H)P by measuring, over each period fraction, the amplitude and possibly the phase of a harmonic of the magnetic field induced in the magnetic material, said amplitude and phase being obtained in response only to an excitation during this period fraction, the harmonic having a frequency nfH, where n is a non-zero positive integer; and the identification and/or the determination of the mass of the magnetic material from several points of the constructed signature S(H).

Abstract: A method for operating of a metal detection system may comprise a balanced coil system with a transmitter coil that is connected to a transmitter unit, which generates transmitter signals having a transmitter frequency that is selected from a group of at least two transmitter frequencies, and with a first and a second receiver coil that provide output signals to a signal input of at least one amplifier unit included in a receiver unit, wherein the output signals compensate each other so that the system is in balance. A system adapted to operate according to an exemplary method is also provided.

Abstract: A controller for a test head module (106) of a test cell (100) includes a control signal generator, an electronic memory device, and a signal evaluation module. The control signal generator to provide control signals to a plurality of magnetic stimulator heads, which provide magnetic stimulus signals to singulated devices for testing in response to the control signals. The electronic memory device stores instructions for controlling concurrent activation of at least two of the magnetic stimulator heads for parallel testing of the singulated devices. The signal evaluation module receives electrical signals from the singulated devices. The electrical signals from the singulated devices are dependent on the magnetic stimulus signals applied to the singulated devices.

Abstract: An automated, non-destructive anhysteretic magnetization characterization method for studying and modeling soft magnetic materials. This measurement method employs a “reading-waveform” that allows multiple points of reference to be established in tracing out the B waveform. In using the reference values from this waveform, the components of B that cannot be measured directly may be calculated with precision. In turn, the initial magnitude of the B waveform is identified as the unknown component of the anhysteretic state. The processes can be repeated for different values of static fields as well as a function of temperature to produce a family of anhysteretic magnetization curves. The core characterization was performed without physically altering the core, so that the true anhysteretic magnetization curve, and the true B-H loop under applied bias H, is measured.

Abstract: The invention concerns a method for producing an assembly of at least one transmission coil (B1) and one reception coil (B2) for eddy current testing, the reception coil receiving in the absence of fault a complex amplitude signal VR, subject to a variation ?VR in the presence of a characteristic fault to be detected. The method consists in selecting the distance ?ER between the axes of the transmission coil and the reception coil so as to maximize the ratio I?VR/VRI.

Abstract: An arrangement and a method for influencing and/or detecting magnetic particles in a region of action includes a selector for generating a magnetic selection field having a pattern in space of its magnetic field strength such that a first sub-zone having a low magnetic field strength and a second sub-zone having a higher magnetic field strength are formed in the region of action. A driver is provided for changing the position in space of the two sub-zones in the region of action by a magnetic drive field so that the magnetization of the magnetic particles changes locally. A receiver is also provided for acquiring signals, which signals depend on the magnetization in the region of action, which magnetization is influenced by the change in the position in space of the first and second sub-zone. Further, a coil arrangement is provided including a surrounding coil and a magnetic field generator such that the surrounding coil almost completely surrounds the magnetic field generator.

Abstract: The present invention relates to an inductive proximity sensor that includes an oscillator having first and second inductor-capacitor circuits arranged such that an inductance of one of the inductor-capacitor circuits has substantially greater sensitivity to an external target than an inductance of the other inductor-capacitor circuit. The sensor also includes an alternating current drive to each of the inductor-capacitor circuits that is in-phase and depends on differences in voltage across the inductor-capacitor circuits. The sensor may be coupled to a calibration device that applies power and triggers a calibration routine within the sensor. In response to the trigger signal, a calibration processor within the sensor executes the calibration routine and adjusts the inductor-capacitor circuits and provides an indication of successful calibration.