Abstract: A hand tool has a handgrip attached to a ground-piercing probe, which is manually insertable in the soil. The probe has a chamber in which at least one inductor is positioned and connected to metal detection circuitry. The preferred circuitry has a pulse generator applying current pulses to an inductor for inducing eddy currents in a buried target object. After the pulse terminates, the decaying coil voltage is sampled at different times to detect both the presence and range of the object, as well as the type of metal in the object. An asymmetric magnetic field pattern about the probe is aligned with a direction pointing indicium on the handgrip and provides directional sensitivity. The coil voltage samples are applied to signaling circuitry, which provides an audible signal which is a series of bursts of an audio tone. The pitch of the audio tone signals the presence, range and bearing of the buried metal object, while the pulse rate of the bursts signals the metal type.

Abstract: A manufacturing method of a MR sensor includes forming a MR multi-layered structure of a first anti-ferromagnetic material layer, a first ferromagnetic material layer (pinned layer) which receives bias magnetic field caused by exchange coupling with the first anti-ferromagnetic material layer, a nonmagnetic material layer and a second ferromagnetic material layer (free layer) which changes its magnetization direction in response to magnetic signal applied thereto, depositing a protection layer on the MR multi-layered structure, removing full depth of at least end regions of the protection layer and a partial depth of end regions of the second ferromagnetic material layer, and forming a second anti-ferromagnetic material layer for exchange coupling to control magnetic domain in the second ferromagnetic material layer, on at least the end regions of the second ferromagnetic material layer.

Abstract: In a rotation angle or rpm sensor having a pulse transducer seated on a rotation element, which has a ring magnet made as an injection molded part and a metal bush that receives the ring magnet by positive engagement, for the sake of a rigid connection between the ring magnet and rotation element, which is favorable from a production standpoint, the ring magnet is received with a first annular portion on the bush and with a second annular portion is seated with a press fit on the rotation element. The bush is fastened to the rotation element in the region of a bush portion that protrudes from the face end of the ring magnet, and the positive engagement between the bush and the first annular portion is made by shaped elements on the outer circumference of the bush, onto which the ring magnet is extruded.

Abstract: A hand tool has a handgrip attached to a ground-piercing probe, which is manually insertable in the soil. The probe has a chamber in which at least one inductor is positioned and connected to metal detection circuitry. The preferred circuitry has a pulse generator applying current pulses to an inductor for inducing eddy currents in a buried target object. After the pulse terminates, the decaying coil voltage is sampled at different times to detect both the presence and range of the object, as well as the type of metal in the object. An asymmetric magnetic field pattern about the probe is aligned with a direction pointing indicium on the handgrip and provides directional sensitivity. The coil voltage samples are applied to signaling circuitry, which provides an audible signal which is a series of bursts of an audio tone. The pitch of the audio tone signals the presence, range and bearing of the buried metal object, while the pulse rate of the bursts signals the metal type.

Abstract: A hand tool has a handgrip attached to a ground-piercing probe, which is manually insertable in the soil. The probe has a chamber in which at least one inductor is positioned and connected to metal detection circuitry. The preferred circuitry has a pulse generator applying current pulses to an inductor for inducing eddy currents in a buried target object. After the pulse terminates, the decaying coil voltage is sampled at different times to detect both the presence and range of the object, as well as the type of metal in the object. An asymmetric magnetic field pattern about the probe is aligned with a direction pointing indicium on the handgrip and provides directional sensitivity. The coil voltage samples are applied to signaling circuitry, which provides an audible signal which is a series of bursts of an audio tone. The pitch of the audio tone signals the presence, range and bearing of the buried metal object, while the pulse rate of the bursts signals the metal type.

Abstract: A magnetic sensor with a signal processing circuit includes a magnetic sensor section 4 composed of a compound semiconductor thin film or a magnetic thin film, and a signal processing circuit 5 for amplifying a magnetic signal the magnetic sensor section detects as an electrical output. The signal processing circuit 5 includes an operational amplifier 51 and a constant current circuit 52 for carrying out feedback. The constant current circuit 52 in the signal processing circuit 5 includes a plurality of resistors with two or more different temperature coefficients, and the current output from the constant current circuit has a temperature coefficient inversely proportional to the temperature coefficient of the combined resistance of the plurality of the resistors.

Abstract: Magnetic characterization of the magnetic field emanating from an RWH device is presented using a magnetostrictive layer as a probe between the device and the scanned SFM tip. The findings suggest a very promising technique to resolve magnetic fields laterally at least in the 100 nm realm. Other magnetosensitive properties such as the magnetoelastic and the piezomagnetic effect can be used in a similar way to infer magnetic characteristics of microstructures or of magnetic multilayers.

Abstract: A chip-detector assembly has a housing and a probe. The probe is adapted to be coupled to the housing. The chip-detector assembly also includes a locking mechanism comprising a locking ring and a sleeve member. The locking ring is fixedly coupled the housing, and includes a plurality of elongated tangs arranged circumferentially around the ring. The sleeve member is fixedly coupled to the probe, and includes a plurality of contact surfaces that form an outer circumference of the sleeve member. The tangs engage the sleeve-member contact surfaces when the probe is coupled to the housing. The engagement of the tangs and the contact surfaces inhibits the probe from disengaging from the housing once the probe and the housing are coupled.

Abstract: A magnetically sensitive sensor for counting pulses for measuring rotational speeds and angular positions of a rotating component via a pulse transmitter connected for rotating with the rotating component automatically adapts its switching points to the respective measurement location conditions. A logic unit initiates automatic adaptation of the switching points from an original state when an operating parameter first exceeds a limit value after the supply voltage of the sensor turned on. The original state is not preset or is coarsely preset. The configuration of the switching points is then stored in a non-volatile data memory specifically for the sensor.

Abstract: A proximity sensing assembly for sensing the proximity of a metallic workpiece to a work holding device includes Hall-effect sensor. The magnetic field generated by the magnet is altered when a metallic workpiece is in close proximity to a magnet. Due to an offset relationship between the sensor and the poles of the magnet, the polarity detected by the Hall-effect sensor is analogous to a reversal when a metallic workpiece is proximate the magnet rather than simply detecting a change in strength. Thus the polarity detected by the Hall-effect sensor sends an clearly defined signal indicating the presence or absence of a workpiece in the work holding device.

Abstract: A magnetic sensor utilizing a giant magnetoresistance (GMR) effect, wherein an insulation layer with a contact hole is formed on a lower terminal layer, a GMR layer is formed thereover on the region including the entire contact hole and at least the surrounding insulation layer, and an upper terminal layer is formed thereover. The sensor offers several advantages in that it is easy to manufacture and is compact, and has a high degree of resistance change.

Abstract: An inductive sensor head for detecting ferrous or non-ferrous electrically conducting objects, in particular rebars in a surrounding medium like concrete or a brick wall, comprising at least one field coil with a small axial length compared to its diameter and at least one twin pair of sense coils with a small diameter compared to the diameter of the field coil. The number of turns of wire on the field coil is small relative to the number of turns of wire on the sense coils. The common axis of the sense coils is arranged perpendicular to the axis of the field coil so that there will be no component or a minimum component of maximum flux that is coaxial with the sense coils. A twin pair of coaxially arranged identical field coils is provided that are sequentially excited for giving not only positional but also depths information. In a center plane between the field coils an orthogonal arrangement of two twin pairs of sense coils is provided enabling for a three-dimensional hidden object positioning.

Abstract: The invention provides an interactive means to locate and identify underground utilities. The apparatus is used with a marker associated with an elongate electrical conductor, which may be a cable shield or a trace wire. It includes a remote, portable probe that is used to transmit a RF signal to be received by a transponder associated with the marker. The transponder is powered by a DC potential on the conductor. In preferred embodiments it has the capability of communicating with a terminal unit over the conductor to transmit information and instructions between the probe and the terminal unit.

Abstract: A combined vacuum cup and sensor is utilized to lift parts. The vacuum cup defines a vacuum chamber between radially inner and outer lips. The sensor is mounted radially inwardly of the inner lip, but is isolated from the vacuum chamber. In this way, parts that are difficult for a larger cup to lift can be lifted easily. Moreover, the sensor need not be provided with a fluid tight seal.

Abstract: Apparatus and methods are disclosed which provide increased sensitivity, selectivity and dynamic range for non-contact measurement of actual physical and/or kinematic properties of conducting and magnetic materials. The apparatus and methods are based upon various methods for increasing sensitivity, selectivity and dynamic range through proper construction of a magnetometer sensor and for proper selection of operating point parameters for the application. A measurement apparatus for measuring one or more MUT properties includes an electromagnetic winding structure which, when driven by an electric signal, imposes a magnetic field in the MUT and senses an electromagnetic response. An analyzer is provided for applying the electric signal to the winding structure. A property estimator is coupled to the winding structure and translates sensed electromagnetic responses into estimates of one or more preselected properties of the material.

Abstract: A method for testing a composite type magnetic head having a MR element and an inductive element includes a current application step of applying a current to the inductive element, with applying no external magnetic field to the magnetic head, and a measurement step of measuring output characteristics of the MR element after the current application step is finished.

Abstract: A small diameter tool for measurement of resistivity of geological rock formations, including a complex auxiliary electrode structure which is adjustable in electrode length between deep and shallow mode measurement operations.

Abstract: A proximity sensor for determining the gap between a sensor and a metal target which is insensitive to noise, changes in temperature of the sensor and different lengths of wire by measuring the AC conductance, DC conductance and susceptance of the sensor and using the measured values with a predetermined data base to derive the desired gap distance.

Abstract: A nondestructive test method determines the degree of metal fatigue of test ferromagnetic construction materials by quantifying a change in effective stress due to aging of the test materials. The disclosed method is to measure the coercive force Hc and the magnetic susceptibility &khgr;H of the test materials at the field of the coercive force Hc. A current tensile stress &sgr; by putting the coercive force Hc and the magnetic susceptibility &khgr;H into the following first equation: &sgr;=a(Hc/&khgr;H)n. where a and n are known constants determined by the internal structure of the test materials. A change in current tensile stress of the test materials is determined by comparing the effective tensile stress &sgr; of the test materials with the initial tensile stress &sgr;0 of the test materials.

Abstract: An apparatus and method used to detect metallized containers or other objects in closed packages traveling in a conveyor stream. The apparatus includes a pair of coil units mounted in association with a packaging conveyor such that the closed packages will pass therebetween. Appropriate field generation circuitry are connected to the coil units for producing a magnetic field. When the metallized containers pass through the magnetic field, the impedance across the coils will vary. The varying impedance is measured continuously, thus giving an indication as to whether the metallized object has been detected. If the package is nonconforming, steps can be taken to automatically remove it from the conveyor stream.