Abstract: To test a conductor with superconductive material which is in the superconducting state, the conductor is led through an external magnetic field which comprises at least two magnetic field regions spatially separated from each other and arranged one behind the other in the lengthwise direction of the conductor, the fields of which are angularly displaced from each other in the circumferential direction relative to the longitudinal axis of the conductor permitting disturbances in all superconductivity regions in superconductors of any cross section to be ascertained with certainty.

Abstract: The present invention relates to an installation for showing up faulty areas on the surface of a bar-shaped, magnetizable workpiece. The installation comprises a feed station and delivery station for the workpiece, and a treatment station, arranged between the feed station and the delivery station, for the introduction onto and fixing of a ferromagnetic powder on the workpiece. The installation includes a support having guide rails between and through the station, clamping devices displaceable along the support and for clamping the workpiece and connecting it to an electrical circuit each clamping device having a drive device with a drive cable. The drive devices are connected with each other by means of a clutch coupling; and, the installation has a control device for regulating operation of the whole installation.

Abstract: A method is provided for balancing the sensitivity of two channels comprising intermittently-appearing pulse waves, such as the signals generated by respective sensors in a detecting couple which is used in the so-called differential detection of flaws in materials. The balancing of the levels of the pulse signals is accomplished by the use of, essentially, a pair of sample and hold circuits, one or two variable gain amplifiers and the same number of comparison loops as variable gain amplifiers.

Abstract: An eddy current flaw detection apparatus which is particularly adapted for inspecting articles at elevated temperatures. A plurality of detectors are supported about at least a portion of a workpiece path of travel to detect and locate flaws in workpieces. A non-magnetic, metallic shield is between the detectors and the workpiece path. A cooling medium is applied to the heat shield to protect the detectors from the heat of a hot workpiece. The cooling medium is also used to purge foreign matter from the assembly.In one embodiment an exciter and detector assembly is disclosed which is constructed as an integral unit encapsulated within moisture-impervious material. In this embodiment, the assembly is movable relative to the workpiece path.In another embodiment, the detectors and the exciter surround the workpiece path.Metallic powder is sprayed on a hot workpiece to mark the location of detected flaws. The heat of the article fuses the marking metal powder in place on the hot workpiece.

Abstract: An electrometer having reduced spacing sensitivity, with the electrometer including a probe with a charge receiving sensor element and a surrounding shield. A voltage equivalent to that sensed by the probe element is fed back to the shield to render the electrometer substantially spacing insensitive. A duty cycle control regulates the width of electrical pulses to a power transformer whose output is fed back to the probe shield to maintain the spacing insensitivity. Means are also provided to automatically test and calibrate the electrometer prior to use.

Abstract: This invention relates to a detector for detecting the relative position of two members, said detector being constituted by a reference mark made on a first member, by a detection member securely connected to the second member and influenced by the coincidence of position of the reference mark with itself, corresponding to said relative position. The reference mark is of substantially punctual type, distinct from other possible reference marks and separated from said other reference marks. One application of the present invention is the detection of the end of stroke of the piston of a jack.

Abstract: A thickness gauge for measuring the thickness of a layer applied to a ferromagnetic base by measuring the attractive force of a permanent magnet in contact with the applied layer is provided with easily removable, interchangeable scales to permit direct reading of thickness in terms of metric, English or other units, or in accordance with the characteristics of the particular magnet used in the gauge.

Abstract: A compact linear transducer assembly including a Hall effect semiconductor material, which material generates a variable voltage as a result of displacing an array of gratings, formed in a first, highly permeable magnetic plate, in a magnetic field relative to the Hall effect material and to a corresponding array of gratings, formed in a second, highly permeable magnetic plate. A counter is responsive to the voltage across the Hall effect material to provide an indication of the linear distance traveled by the movable grating plate.

Abstract: A magnetic field sensor housed in a cooling device has an inner core body for measuring the behavior of a charge put in a shaft furnace, an inner casing for accommodating the inner core body therein, and an outer casing for accommodating the inner casing with a space for a circulating path of cooling medium therebetween. The inner core body consists of an exciter for exciting the charge put in the furnace, a magnetic field sensing member arranged in front of the exciter for detecting the exciting magnetic field generated from the exciter and a driving circuit arranged at the rear of the exciter for driving the sensing member.

Abstract: Disclosed are several embodiments of a disposable sample card for testing fluids such as blood and the like. A generally planar card contains a chamber, or well and supports two insulated electrodes which terminate in the region of the well. Various electrode configurations are disclosed, each adapted to associate with an instrument for applying an electric voltage between the two electrodes, and across the sample under study. Also disclosed is an instrument for receiving the specially shaped sample cards.

Abstract: An eddy current flaw detection apparatus which is particularly adapted for inspecting articles at elevated temperatures. A plurality of detectors are supported about at least a portion of a workpiece path of travel to detect and locate flaws in workpieces. A non-magnetic, metallic shield is between the detectors and the workpiece path. A cooling medium is applied to the heat shield to protect the detectors from the heat of a hot workpiece. The cooling medium is also used to purge foreign matter from the assembly.In one embodiment an exciter and detector assembly is disclosed which is constructed as an integral unit encapsulated within moisture-impervious material. In this embodiment, the assembly is movable relative to the workpiece path.In another embodiment, the detectors and the exciter surround the workpiece path.Metallic powder is sprayed on a hot workpiece to mark the location of detected flaws. The heat of the article fuses the marking metal powder in place on the hot workpiece.

Abstract: A system of detecting a change in the charge put in a metallurgical furnace or the like wherein an magnetic field generator and a magnetic sensing section of a magnetometer arranged along the central axis of the exciting magnetic field of the said magnetic field generator are fitted in place on and/or inserted into a hole of the wall of such a vessel, including a metallurgical furnace or the like, as is enclosed with the said wall, such a change in the exciting magnetic flux passing through the said magnetic sensing section as is given birth by the movement of the charge is picked up in the form of electrical signals, and, the movement, the velocity, the rate of travel, the thickness of the layer, fluctuations in the shape of the layer, the circumferential distribution, the classification, and so forth, of the said charge are enabled to be properly detected in an optional manner through corresponding changes in the said electrical signals.

Abstract: A method for forming and preserving a permanent record of inspections of workpieces or the like having drilled holes or other metallic surface conformations characterized by applying a castable, plural component, magnetically active material comprised of room temperature vulcanizing, or polymerizing, rubber containing magnetizable particles and specific sensitizing agents; magnetizing the area to be inspected, so as to cause migration of the particles in the rubber before the viscosity becomes too high for the magnetized particles to migrate to the situs of an imperfection, or flaw; forming a magnetic rubber inspection replica or record of the alignment of the magnetizable particles adjacent the interface between the casting and the workpiece by increasing the viscosity of the rubber above 4000 centipoises and to flexible elastic form so as to immobilize the particles; removing the magnetic rubber inspection record thus formed and inspecting for concentrations of the magnetizable particles to delineate flaws;

Abstract: A magnetic orientation sensor for magnetic recording media includes a transducer that writes a magnetic pattern on the recording medium and then reads it back. The reading is taken a number of times at a given location but with the magnetic flux traveling in various directions. The strength of the readback signal is used to interpret the magnetic properties of the medium, in particular a direction of orientation which is the preferred or strongest magnetic conductor. The transducer and the medium are stationary with respect to one another at each measurement. The transducer or magnetic head consists of a circular or ring-type structure having a rotating center spindle having a longitudinal bar of magnetic conductive material on the face thereof to create a magnetic field of varying orientation during the writing and reading process.

Abstract: A displacement transducer in which two toothed members have magnetic poles arranged in alternating sequence. The toothed members cooperate so that one magnetic pole on one of the members is spaced from a magnetic pole of opposite polarity on the other member. The magnetic poles, furthermore, are spaced so that magnetic flux lines pass through the space or air gap between poles of opposite polarity. A magneto-resistive element is held within that air gap between magnetic poles, and is intercepted by the magnetic flux lines. This magneto-resistive element has an electrical resistance which is dependent on the angular orientation and magnitude of the flux lines with respect to the element. By measuring the electrical resistance of the magneto-resistive element, the angular orientation of the flux lines and thereby the relative displacement of the toothed members may be obtained.

Abstract: The described tube testing apparatus indicates whether a defect is either external or internal, enabling a quantitative classification of defects and an analog representation on location of the defect in the tube wall. The ratio of the signal levels of a defect is taken as a threshold in two different circuit channels. For tubes of a given wall thickness, the ratio of the defect signal levels resulting in the two channels is a fixed number which is a function of the location of a defect in the tube wall causing a defect signal. Uninfluenced test signal voltages from the first channel are available for further evaluation and are applied to voltage discriminators having various threshold voltages.

Abstract: Apparatus for measuring the wall thickness of a moving tube, for example an extruded tube of synthetic plastics material, comprises means for location in a stationary position within the tube and adapted to present at least one measuring body in resilient contact with the inner wall of the tube, and an external sensor for sensing the position of the measuring body. A mechanical linkage incorporating means engaging the tube wall is arranged to lift the measuring body away from the tube wall when excessive friction between the tube wall and the engagement means indicates a condition liable to damage the measuring body.

Abstract: To suppress stray noise pulse in inductive pick-ups located in magnetic relation to a rotating body, typically the flywheel of an internal combustion engine, so that the instantaneous shaft position can be accurately determined, to accurately compute an ignition instant, fixed or stationary pick-up transducer is formed with an E-shaped core having outer legs and a central leg, the pick-up coil being wound on the central leg, and the magnetic element, typically a permanent magnet rotating with the shaft of the engine, having a width to match essentially only the width of the central core and passing in a plane transverse to the plane of the core, so that the outer legs of the core will act as shields against stray noise pulses. The core can be constructed as a circular element of a central core within a tubular magnetic structure, the E-shaped configuration being obtained by slotting the outer tubular structure.

Abstract: The present invention relates to devices intended to measure magnetic fields, and also known as magnetometers. It consists in using a zeroing method to measure the influence of the Faraday effect of the field being measured, upon a radiated energy beam propagating in guided fashion through a thin film of magnetic material.

Abstract: An improved electromagnetic scanner has a substantially E-shaped core having an outer surface that is positioned, at a predetermined air-gap spacing, from a regularly grooved ferromagnetic surface of a textile machine. A pair of coils extend around the crosspiece of the core between the outer arms of the core and the middle arm thereof, such coils being connected in series and connected to a bridge circuit to generate an electrical indication that varies at the rate of movement of the grooved ferromagnetic surface past the core in a direction crossing the grooves in the surface. The plane of said core is oblique to the grooves. A pair of abrasion-resistant, non-magnetic contact elements supported in the spaces between the arms of the core, projecting outwardly into the air gap, and are urged into contact with the moving ferromagnetic surface by a spring carried in a housing in which the core and coils are mounted.