Abstract: A sensor for measuring the surface level of a liquid phase metal includes an air excitation coil and lower and upper air reception coils. Excitation coil is perpendicular to an upper surface of an ingot mold and powered by a current for generating a magnetic field. Magnetic field lines propagate along upper field lines away from the ingot mold and along lower field lines covering the upper surface and the molten metal surface. Lower air coil is parallel to the excitation coil, whereby an induced voltage is generated by the lower field lines, the latter being modified by varying the level of the metal surface. Upper air coil is parallel to the excitation coil, vertically adjacent to the lower air coil, with a shape and characteristics identical to the lower air coils. Upper field lines generate the induced voltage and are substantially free of disturbances generated by the metal surface.

Abstract: Systems and methods for sensing external magnetic fields in implantable medical devices are provided. One aspect of this disclosure relates to an apparatus for sensing magnetic fields. An apparatus embodiment includes a sensing circuit with at least one inductor having a magnetic core that saturates in the presence of a magnetic field having a prescribed flux density. The apparatus embodiment also includes an impedance measuring circuit connected to the sensing circuit. The impedance measuring circuit is adapted to measure impedance of the sensing circuit and to provide a signal when the impedance changes by a prescribed amount. According to an embodiment, the sensing circuit includes a resistor-inductor-capacitor (RLC) circuit. The impedance measuring circuit includes a transthoracic impedance measurement module (TIMM), according to an embodiment. Other aspects and embodiments are provided herein.

Abstract: The invention relates to a sensor arrangement for use in a sensor bearing with a magnetic ring (14) with multiple pole pairs, the sensor arrangement including at least three magnetic sensors (16) and to a sensor bearing using such a sensor arrangement. It is proposed that the at least three magnetic sensors (16) are encapsulated in a prefabricated package (17).

Abstract: A system and method for detecting damage to a door system by detecting the presence or absence of a magnetic source attached to the door system for stopping motion or reversing motion of the door to prevent any further damage to the door system. For example, a roll-up type door may be damaged by a vehicle and pulled from its vertical support guides; detecting this event causes stopping of any motion of the door, such as opening or closing the door.

Abstract: A permanent magnet 60 for biasing is placed between opposite surfaces of a second stationary magnetic body 20 and a third stationary magnetic body 30, and a range in magnetic flux density detected by a magnetic sensor 50 is changed to thus include zero in the magnetic flux density. A correction and an adjustment of a temperature characteristic and so on of the magnetic sensor 50 are performed in a state of zero in the magnetic flux density.

Abstract: A position sensing head combines a sensing element and a simplified electronic module to enable operation with one wire, in addition to a circuit common, for providing power and transmitting a signal, while separating the sensing head from signal conditioning circuits by over 10 meters. The simplicity of the electronic module allows the use of basic electronic components that operate at more than 225° C. The signal is a variable frequency impressed onto the one wire, which can be read by a frequency meter. Another signal, such as a position or temperature, can be impressed onto the one wire at the same time as the first signal. The second signal is of a different frequency range so that it will not interfere with the first. A demodulator circuit can separate the two signals. The sensing element construction allows for locating up to three active elements measuring the same target.

Abstract: An apparatus and a method provide an output signal indicative of a speed of rotation and a direction of rotation of a ferromagnetic object capable of rotating. A variety of signal formats of the output signal are described.

Abstract: A method of improving linear position sensing of clutch actuators with magnetic field sensors utilizes a dedicated magnetic field sensor solely to detect the ambient magnetic field. Typical three position hydraulic clutch actuators include a pair of active magnetic field sensors, one of such active sensors associated with each of a pair of pistons in such actuator and an adjacent pair of permanent magnets, one of such magnets associated with each of such pistons. The invention provides an additional magnetic field sensor disposed proximate the active magnetic field sensors which senses the surrounding (stray, background or parasitic) magnetic field proximate the active magnetic field sensors and provides a signal to an electronic circuit or software which actively and in real time corrects the signals from the active magnetic field sensors by cancelling out the magnitude of the stray magnetic field as detected by the additional sensor.

Abstract: An apparatus and a method provide an output signal indicative of a speed of rotation and a direction of rotation of a ferromagnetic object capable of rotating. A variety of signal formats of the output signal are described.

Abstract: A position detection device includes a first component provided by molding of a first mold resin with a first hall IC, a second component provided by molding of a second mold resin with a second hall IC, a terminal connected to a first wiring of the first component and to a second wiring of the second component, and a third mold resin molded to hold and protect the first component, the second component and the terminal. The third mold resin fixing the first component and the second component to each other. Accordingly, the position detection device can be provided, which includes a component usable commonly for a variety of position detection devices which are different in the number of hall ICs.

Abstract: A permanent magnet includes magnetic poles that are arranged so as to alternate in polarity in the circumferential direction of the axis of rotation. The magnet is attached to one of a pair of rotatable members. The rotatable members are relatively rotatable about an axis of rotation. A magnetic flux inducing ring, including an annular ring body and a plurality of protrusions protruding from the ring body, is attached to the other rotatable member. A plurality of magnetic sensors is arranged adjacent to the ring body. A first facing portion and a second facing portion, each for inducing a part of a magnetic flux of the ring body, are provided and do not rotate with the permanent magnet and the magnetic flux inducing ring.

Abstract: In one embodiment, a method comprises driving one or more drive electrodes formed on a substrate with one or more drive signals. A wiper comprising at least one arm is driven to a predetermined voltage. The wiper is electrically insulated from a plurality of sense electrodes formed on the substrate. For each sense electrode of the plurality of sense electrodes, a charge stored by the sense electrode is detected. A processor determines a position of the wiper based on the detected charges stored by the plurality of sense electrodes.

Abstract: Systems and methods for determining a position of a movable component. One system includes a controllable source of varying magnetic flux. In a particular embodiment, the magnetic flux is directed through a magnetic sensor using a first flux concentrator and a second flux concentrator. The sensor generates a sensor signal that is provided to an electrical circuit designed to demodulate the signal. The demodulated signal is provided to a controller. The controller converts the signal and calculates the position of the second flux concentrator relative to the first flux concentrator. The controller may take a predetermined action based on the calculated position of the second flux concentrator.

Abstract: A circuit to detect a movement of an object provides a threshold selection module that uses one or more threshold signals identified prior to a present cycle of magnetic field signal in order to establish a threshold signal used for a present cycle of the magnetic field signal. A method associated with the circuit is also described.

Abstract: The present invention provides a single component implementing highly precise pulse detection for rotational or liner position detecting apparatuses for jog dials and mechanical products. Focusing on the fact that the phase difference between the magnetic fields in circumferential and radial directions generated by a magnetized ring is precisely 90 degrees, a position detecting apparatus of the present invention includes two Hall elements placed at a distance; a protective film provided on magnetic sensitive portions of the two Hall elements to cover the magnetic sensitive portions; a thin-film magnetic plate placed on the protective film to cover the magnetic sensitive portions of the two Hall elements; and further a processing circuit calculating the sum and difference of the signals from the two Hall elements to generate signals having an accurate phase difference of 90 degrees. The position detecting apparatus can therefore detect the rotation direction and precise rotation angle.

Abstract: One embodiment of the present invention relates to a magnetic sensor circuit having a magnetic field sensor device configured to generate a digital signal proportional to an applied magnetic field. An analog-to-digital converter converts the analog signal to a digital signal that is provided to a digital signal processing unit, which is configured to digitally track the analog output signal. The digital tracking unit comprises a delay removal circuitry configured to generate a plurality of digital signal component corresponding to a chopping phase. A non-delayed offset compensated digital output signal may be generated within the chopping phase by mathematically operating upon (e.g., adding or subtracting) the plurality of digital signal components, generated by the delay removal circuitry.

Abstract: A rotation angle detector for detecting a rotation angle of a magnet rotator includes: the rotator with a magnet mounted on a rotation shaft; a sensor chip; and an operation element. The chip includes: first and second normal component detection elements for detecting a magnetic field along with a normal direction and first and second rotation component detection elements for detecting a magnetic field along with a rotation direction.

Abstract: An angle sensor for determining a rotation angle of a rotatable body, such as a steering column in a motor vehicle, includes a gear wheel. The orientation of a magnetic field generated by the gearwheel is configured to be detected by a magnetic field sensor. The gear wheel is comprised of a magnetisable material, such as hard ferrite, into which a magnetisation is introduced. The gear wheel is stronger in a central region than in an edge region in which the teeth are arranged. In order to weakly magnetise the edge region, which minimizes a negative influence of the teeth on the homogeneity of the generated magnetic field, the front face of the gear wheel is configured to be magnetized. The magnetisation process advantageously takes place at the same time as an injection moulding process to form the gearwheel. A method is implemented to produce the gear wheel.

Abstract: Flow valve comprising a casing (1) containing an electromagnetic assembly (2) for detecting a magnetic field, the electromagnetic assembly being fixed to a pendulum (3) suspended by an articulation (6) from a wall (5) of the casing, the casing containing a liquid for damping the movements of the pendulum, characterized in that the pendulum comprises opposite the articulation a surface (8) which has a spherical cap shape and which extends facing a wall (4) of the casing of complementary shape, defining a space having, dimensions suitable for producing a laminar rolling of the damping liquid between them, when the pendulum is in motion.

Abstract: A linear sensor is described with a casing (5), with a pin (7) which contains a permanent magnet (1) and which is mounted in the casing (5) in a linearly displaceable manner against the force of a spring (6), and with a magnetic field sensor (3) attached to said casing (5) for detecting of a displacement of the permanent magnet (1). The invention provides that the pin (7) is controlled by a first cylindrical guide (8) and a second cylindrical guide (8).

Abstract: A magnetic field sensor for measuring a direction of a magnetic field in a plane having two sensing structures (1A; 1B) that can be operated as a rotating Hall element. The two Hall elements are rotated in discrete steps in opposite directions. Such a magnetic field sensor can be used as current sensor for measuring a primary current flowing through a conductor (15).

Abstract: A measuring device for measuring a film thickness of a silicon wafer (1) comprises: position and velocity sensors (4) linearly arranged along a longitudinal direction into first and second position and velocity sensor arrays spaced apart from each other in a lateral direction, in which the position and velocity sensors (4) in the first position and velocity sensor array are in one-to-one correspondence with the position and velocity sensors (4) in the second position and velocity sensor array in the lateral direction; an eddy current sensor (2) disposed in a symmetrical plane between the first position and velocity sensor array and the second position and velocity sensor array and perpendicular to the lateral direction; and a controller connected to the position and velocity sensors (4) and the eddy current sensor (2) respectively for controlling measurement of the thickness of the film according to detection signals from the position and velocity sensors (4) and the eddy current sensor (2).

Abstract: A rotation angle sensor outputs detection signals based on a rotation angle of a rotary shaft. The detection signals that are output from the rotation angle sensor include first to fourth detection signals that sinusoidally change with the rotation angle of the rotary shaft and that are different in phase from one another. Here, a phase difference between the first detection signal and the second detection signal and a phase difference between the third detection signal and the fourth detection signal are each set to 90°. In addition, a phase difference between the first detection signal and the third detection signal and a phase difference between the second detection signal and the fourth detection signal are each set to 45°.

Abstract: The present invention relates to a method for producing a magnetic substrate for an encoder scale. The method comprising the step of mechanically working the substrate, wherein the substrate is cooled prior to the mechanical working step. In one embodiment, a stainless steel substrate is used. The stainless steel may comprise an austenite (non-magnetic) phase and a martensite (magnetic) phase. Mechanically working and cooling in this manner increases the amount of magnetic (martensite) phase material that is formed, thereby improving the magnetic contrast when non-magnetic (austenite) marking are subsequently formed on the substrate by laser marking.

Abstract: A system and method for performing object localization based on the emission of electromagnetic fields. The electromagnetic fields are simultaneously emitted from different transmitters. One electromagnetic field is emitted at a base frequency; the remaining waves are emitted at frequencies that are harmonics of the base frequency. The composite magnetic fields are measured by sensors. The signal generated by each sensor is subject to a Fourier analysis to determine the strengths of the individual electromagnetic fields forming the composite electromagnetic field. These individual measure field strength data are then used to determine the position and orientation of the sensors relative to the transmitters.

Abstract: An apparatus for determining the position of the rotor of an electric machine in relation to the stator, wherein the electric machine has at least three winding phases, which each have at least one pole winding with a magnetizable core, with devices for detecting a measurement signal. The instantaneous degrees of magnetization of the pole winding cores influenced by the magnetic field of the rotor, depend on the position of the rotor. The devices for detecting the measurement signal for tapping off the measurement signal are provided exclusively outside the electric machine at connecting conductors used for energizing the electric machine. Preferably, switching devices for temporarily isolating at least one of the connecting conductors from an operating voltage source are provided, wherein the measurement signal can be tapped off at the connecting conductor which has been isolated from the operating voltage source.

Abstract: A retractable assembly for immersion-, flow- and annex-measuring systems in analytical process technology for measuring at least one measured variable of a medium in a process containment, comprising an essentially cylindrical housing having a housing interior; an immersion tube, which is axially movable between a retracted service position in the housing and a process position extended from the housing. In the service position, the immersion tube is positioned in the housing interior; a closure element on an end region of the immersion tube facing the medium for sealing off the housing interior from the process containment when the immersion tube is located in the service position, and a proximity detector in or on the end region of the housing facing the medium for detecting the closure element in the service position.

Abstract: A simple position determination is enabled by a device and a method to determine the position of a local coil in a magnetic resonance apparatus, wherein at least one signal emitted by at least one transmission coil is received by the local coil and is evaluated with a position determination device in order to determine the position of the local coil.

Abstract: The present invention provides a gear absolute position sensor assembly (GAPS) that senses the current absolute, position of the shift lever of a manual transmission. The sensor assembly provides data to an associated electronic controller such as an engine control module (ECM) regarding the current position of the shift lever, such as an engaged gear. The sensor assembly preferably comprises at least one Hall effect or other type of magnetic field (proximity) sensors in combination with an application specific integrated circuit (ASIC) which is supplied with data from the sensors, decodes the output of the sensors and provides an output identifying a specific engaged gear or neutral for use by vehicle or engine management electronics. The sensors are mounted proximate the shift linkage at a location where they can sense both rotation and translation.

Abstract: A length measurement apparatus (10) has a bistable magnetic element (102), an elongated physical scale (200) with a plurality of measurement graduation elements (202) spaced apart from one another and a reading head (100) movable relative to the physical scale (200) in its longitudinal extent and which includes a first and second reading head magnet (114a b) arranged transverse to the longitudinal extent and with opposite polarity to one another. The measurement graduation elements (202) each have a magnetic short-circuit element (202) to suppress the magnetic field (116a) of the first reading head magnet (114a) in a first relative position of the reading head (100) and the magnetic field (116b) of the second reading head magnet (114b) in a second relative position of the reading head (100).

Abstract: Position sensor (10) for determining a linear position in a sensing direction, e.g. for application in a vacuum actuator. The position sensor (10) has a first sensor part and a second sensor part moveable with respect to each other. The first sensor part comprises an annular magnet (2) and a magnetic field sensor (3) positioned at a first distance (l1) from the annular magnet on the magnet axis (1a). The second sensor part comprises a flux shaper (1) moveable through the annular magnet (2) along the sensing direction between a first and a second position, in the first position the flux shaper being substantially at the first distance (l1) from the magnetic field sensor (3). The flux shaper is arranged to influence the magnetic field in a space between the annular magnet (2) and the magnetic field sensor (3).

Abstract: A transducer has a magnetic field concentrating member a first coil to couple with a first portion of the magnetic field concentrating member positioned adjacent the first coil and a second coil to couple with a second portion of the magnetic field concentrating member positioned adjacent the second coil, the second portion being spaced along the magnetic field concentrating member from the first portion. The transducer comprises a resonator having a coil wound around a portion of said magnetic field concentrating member which is located between said first and second portions. The transducer is arranged so that the electromagnetic coupling between the resonator and at least one of the first and second coils varies as a function of the relative position between the elongate field concentrating member and that coil. In this way, separate processing electronics can process the signals obtained from the transducer to determine the desired position information.

Abstract: A capacitive rotary encoder has a stator and a rotor as well as stator electrodes firmly arranged at the stator on an encoding path coaxial to the rotor axis, and coupling electrodes arranged at the rotor. The coupling electrodes are guided over the stator electrodes at a small axial distance from the encoding path by rotation of the rotor, wherein they each cover stator electrodes adjacent in the peripheral direction and connect the latter capacitively to each other. Interrogation electronics detects for each of the stator electrodes a capacitive coupling with an adjacent stator electrode caused by a coupling electrode of the rotor. This permits the reliable detection of the angular position of the rotor both statically and dynamically.

Abstract: A sensor with multiple magnetic field sensing elements for use in current sensing and other applications is presented. The sensor includes an arrangement of two or more magnetic field sensing elements to sense magnetic field associated with a target. The sensor further includes circuitry to generate a sensor output signal based on sensing of at least one of the magnetic field sensing elements of the arrangement. Also included is a programmable misalignment adjustment block to control the circuitry to generate the output signal with compensation for misalignment between the sensor and the target. The programmable misalignment adjustment block can be programmed to select measurement of one of the two or more magnetic field sensing elements, or alternatively, a mathematical combination of measurements of the two or more magnetic field sensing elements, for generating the sensor output signal when a test of the sensor indicates a misalignment.

Abstract: A throttle opening detection device includes a rotor which is rotated in an interlocking manner by manipulation of an acceleration grip which is mounted together with the rotor on a handlebar. First magnets are arranged near a peripheral portion of one side surface of the rotor along the circumferential direction of the rotor, while second magnets are respectively laminated to the first magnets, and have opposite polarities to the first magnets. The first magnets with the second magnets laminated thereto are disposed with a set spacing therebetween. A magnetic sensor for detecting a magnetic force generated by all the magnets is arranged to oppose, with a clearance therebetween, the one side surface of the rotor in which the magnets are arranged, in an axial direction of the rotor.

Abstract: An indoor navigational system determines a location of a moveable object in an indoor area and displays this location to a user. The system includes an absolute position sensor coupled to a case attached to a moveable object including a motion sensor coupled to a case including a first magnetic field sensor configured to detect a polarity of a magnet as the magnet passes in proximity to the first magnetic field sensor, a code wheel having two or more magnets alternately oriented with north and south polarities facing toward the first magnetic sensor, the code wheel positioned to rotate in unison with a wheel of the moveable object, and encoder circuitry configured to determine an amount of rotation of the wheel of the moveable object based on an output of the first magnetic field sensor.

Abstract: A fluidic media detection system for detecting a presence of fluidic media includes a first housing portion adapted to be carried by a user; a second housing portion configured to be selectively operatively engaged with and disengaged from the first housing portion, the second housing portion for supporting a reservoir having an interior volume for containing fluidic media; a fluid conduit supported by one of the first housing portion and the second housing portion for providing fluid communication between the reservoir and the user when the first housing portion and the second housing portion are operatively engaged; and at least one interactive element, positioned near a portion of the fluid conduit, that interacts with the fluidic media when the fluidic media is present in the fluid conduit.

Abstract: The magnetic-field direction measuring apparatus includes a substantially rectangular rotation angle measuring chip, and a first magnetic field sensor and a second magnetic field sensor disposed substantially on a circumference centered around a predetermined point on a surface of the rotation angle measuring chip serving as a circle center point, the first magnetic field sensor detecting a magnetic component in a first direction, the second magnetic field sensor detecting a magnetic component in a second direction different from the first direction. The first magnetic field sensor and the second magnetic field sensor are positioned line-symmetrically with respect to a straight line on the surface of the substrate which is parallel to a longitudinal direction of the rotation angle measuring chip or a transverse direction of the rotation angle measuring chip and which serves as an axis of symmetry.

Abstract: The clearance between a stationary object (such as a gas turbine engine casing) and one or more moving objects (such as the blades of a rotating turbine) is measured using a pair of electrical proximity sensors mounted on the stationary object with their sensitive fields directed towards the path of the moving object(s) and at angle to each other. The clearance is calculated by deriving a time interval between interceptions of the respective moving object with the sensitive fields of the two sensors and from the geometry of the set up.

Abstract: An apparatus for determining the position of the rotor of an electric machine in relation to the stator. The machine has multiple phases, each of which includes at least one pole winding with a magnetizable core. The apparatus includes devices for detecting measurement signals that are characterized by the momentary degrees of magnetization of the pole winding cores. The degrees of magnetization are influenced by the angular position of the magnetic field of the rotor. The devices are also used to detect the currents in the phases and determine the angular position of the rotor from the detected measurement signals, taking into account a contribution of the phase currents to the degrees of magnetization of the pole winding cores.

Abstract: A control system for use in safety critical human/machine control interfaces is described, more particularly a joystick type control system and particularly a joystick type control system utilizing magnetic positional sensing. The control system provides a control input device having a movable magnet, a pole-piece frame arrangement positioned about the magnet, at least three magnetic flux sensors being positioned in said pole-piece frame arrangement and a monitoring arrangement for monitoring the output signal of each of said at least three sensors.

Abstract: A sensor assembly is sandwiched together with a rubber material mixed with a vulcanizing agent in a mold assembly including an upper mold and a lower mold. The upper and lower molds, while completely sandwiching the sensor assembly, are heated for a predetermined length of time, and a pressure is then applied to the sensor assembly to complete a compressive molding.

Abstract: A method and measurement arrangement are disclosed for measuring mechanical stress in ferromagnetic workpieces, in which a ferromagnetic workpiece impresses a magnetic field and a magnetic field value is measured and analyzed with respect to the mechanical stress. The method includes at least two exciters of the magnetic field arranged along a longitudinal extension of the workpiece such that a section of the workpiece is located between the two exciters of the magnetic field. A direction-dependent magnetic field sensor is arranged at a position along the longitudinal extension of the workpiece, which can be at half the distance between the two exciters of the magnetic field. With the direction-dependent magnetic field sensor, the change in position and/or the direction of a dividing line between the north and south poles of the impressed magnetic field is determined and analyzed.

Abstract: A relative bearing sensor for determining an orientation of a device. The relative bearing sensor including a ferromagnetic housing, and wherein the ferromagnetic housing includes a ferromagnetic ball configured to roll with respect to an orientation of the ferromagnetic housing, a magnetic flux sensor, a permanent magnet configured to emit a plurality of magnetic flux lines through the magnetic flux sensor, the plurality of magnetic flux lines steered by a location of the ferromagnetic ball, and a processor programmed. The processor is programmed to determine a flux angle of the plurality of magnetic flux lines, compare the determined flux angle with a predefined flux angle, and determine an orientation of the relative bearing sensor based on the comparing.

Abstract: A rotation angle sensor for detecting an absolute rotation angle upon single or multiple revolutions includes a magnetic field sensor and an encoder arrangement. The magnetic field sensor detects at least two orthogonal magnetic field variables. The encoder arrangement is rotatable depending on the absolute rotation angle relative to the magnetic field sensor, such that the magnetic field detected by the magnetic field sensor is dependent on a relative angular position of the encoder arrangement with respect to the magnetic field sensor. The encoder arrangement is furthermore displaceable relative to the magnetic field sensor. The relative angular position and the relative translational position of the encoder arrangement with respect to the magnetic field sensor is determined from the at least two orthogonal magnetic field variables. The absolute rotation angle is determined by means of the relative angular position and the relative translational position.

Abstract: A motor vehicle gearbox position sensor includes a magnet and a probe for measuring a magnetic field at a sensitive end. The magnet and the probe may be placed facing a moving target connected to an actuating element, which is used to select the gear ratios of a gearbox in order to determine the position of the target in space and, from this, deduce the position. The position sensor also includes at least one ferromagnetic element positioned at the periphery of the sensitive end to trap metallic contaminants. A motor vehicle gearbox includes an actuating element that selects gear ratios, a moving target connected to the actuating element, and a position sensor.

Abstract: The invention relates to a path measuring apparatus comprising at least a first measuring path and a second measuring path, these measuring paths each having an extension in a longitudinal direction and being oriented parallel to one another in at least a measuring range, at least one position indicator which couples to the measuring paths in a non-contact manner, and a measuring path holder which extends in the measuring range and has recesses, each recess having a measuring path arranged therein.

Abstract: The design and use of a simplified, highly efficient, waveguide-based wireless distribution system are provided. A low-loss waveguide is used to transport wireless signals from a signal source or sources to one or more receiver locations. One or more adjustable signal coupling devices partially insert into the waveguide at predetermined locations along the length of the system to provide variable, controlled extraction of one or more wireless signals. Low-loss impedance matching circuitry is provided between the waveguide coupling devices and output connectors to maintain high system efficiency and the capability of supplying signals of high strength and quality to a large number of receivers in a wide wireless coverage area via a plurality of signal radiators. Some embodiments of the system are adaptable for wireless distribution service in HVAC plenum spaces while others disclose the combined functions of fire extinguishing and waveguide wireless distribution.

Abstract: A method for measuring surface profile of a sample, wherein jumping of a probe can be constrained without applying strong force to the sample, and an apparatus employing such a method. Control operation consists of detection of displacement in a probe in the vertical direction on the top surface of a sample being measured by means of a sensor, calculation of velocity and acceleration of the probe in accordance with detection of the displacement in the probe, detection of jumping of the probe through real-time monitoring of at least either velocity or acceleration of the probe, and a control of the current delivered to a stylus pressure generator for the probe. Such a control operation is performed in a small amount of time, and a stylus pressure applied to the probe is increased only while the probe is in the air, while the stylus pressure applied to the probe is returned to an original pressure before the probe touches the sample again.

Abstract: A linear position sensor assembly having a magnetic shield minimizes interference (noise) from adjacent electrical and electromagnetic devices, particularly solenoids. The sensor assembly includes a permanent magnet linear contactless displacement (PLCD) sensor comprising a pair of magnetic field sensors which are spaced apart by a member of high magnetic permeability such as a metal bar. The sensors and metal bar are enclosed, i.e., surrounded on three sides, by a cover or shield of high magnetic permeability material such as steel or mu metal, for example. A permanent magnet is disposed in sensed proximity to the sensors and translates with a clutch actuator component. When the clutch actuator component translates axially, the two field sensors provide a signal to associated electronics having high linearity, low noise and no deadband.