Abstract: Hall-effect position sensor apparatus is disclosed which senses the position of a moving body and provides an output signal indicative of the position of the moving body. The apparatus includes a predetermined number of Hall-effect sensors which are positioned in a straight line and in operating proximity to a moving body made of a ferromagnetic material. A permanent magnet is operatively positioned such that the Hall-effect sensors lie in the magnetic field produced by the magnet while the moving body provides a portion of the path comprising the magnetic excitation circuit with the permanent magnet. The moving body includes portions devoid of ferromagnetic material, which causes a change in the magnetic field.

Abstract: The present invention relates to an improved position monitoring system for use in monitoring the positional relationship of two members mounted for relative movement with respect to each other. In such apparatus, a pair of magnetic fields are juxtaposed to each other such that they have opposite polarity and are of such a field strength that they provide for a generally linear variation in field strength extending over an elongated path which traverses the abutment of said fields. In a preferred embodiment, such a system is employed as an integral part of an electromagnetic actuator wherein the magnetic fields interact with the electromagnetic fields of a suitably positioned field coil. The monitoring is used to provide closed loop control of the positional relationship between the two members.

Abstract: Call switch for use by hospital patients and staff members to summon aid in wet areas such as shower and bath areas. An actuating magnet is positioned on the front side of a waterproof panel for controlling the operation of electronic circuitry mounted in a dry area behind the panel. The magnet is carried by a slide for movement between rest and tripped positions, and a pull cord is connected to the slide by a breakaway member which permits the cord to separate from the slide when a patient becomes entangled in the cord or the pull on the cord otherwise exceeds a predetermined limit.

Abstract: The present invention comprehends a magnetic mark detector system in which the magnetic detector head is customized to the magnetic span of the North/South poles of a magnetic mark on a cable and is focused to concentrate the specific magnetic characteristics of flux of the magnetic mark to a detector and to exclude the effects of extraneous earth magnetic fields. The magnetic head structure includes spaced apart elongated head members constructed from magnetic material and disposed in an end to end relationship. The head members have an overall length functionally related to the magnetic span of a magnetic mark and focus magnetic flux. Between facing ends of the head members, in a centrally located gap, is a Hall field effect device which responds to magnetic flux and produces an electrical output signal.

Abstract: A Hall device is formed from a generally rectangular body of material exhibiting the Hall effect, with two excitation electrodes disposed along opposite edges of the device. Two Hall output voltage electrodes are disposed along one of the remaining edges of the main body and at least one additional output electrode is disposed on the edge of the main body opposite the first pair of electrodes. At least two of the output electrodes are offset from a centerline drawn through the electrical midpoint of the main body. By deliberately offsetting the Hall voltage output electrodes from the centerline the first and second order voltage offsets due to inhomogeneities of the Hall material and mask misalignment are eliminated or easily compensated.

Abstract: An alternating magnetic excitation field is generated in the flux concentrators (11,12) of a Hall effect device, including a Hall element (13), by passing an a.c. current through a coil (14). This alternating field serves to drive the flux concentrators into and out of saturation. In the presence of a d.c. magnetic field and when a Hall current is applied to the Hall element, a second harmonic component is generated in the output voltage of the Hall element (13); the amplitude of the second harmonic component providing a measure of the d.c. magnetic field. In an alternative arrangement (FIG. 4) the flux concentrator means is in loop form rather than in a flat configuration as in FIG. 3.

Abstract: The object of the invention is a device with two Hall generators (12, 14) for measuring the gradients of magnetic leakage fields in the non-destructive testing of materials. The two Hall generators (12, 14) are arranged at a distance from each other with their broad sides on a flat carrier substrate (18). They are positioned along a common line (36) with respect to which they each have the same alignment. Furthermore the two Hall generators are arranged close to the edges (40) of two opposite sides of the carrier substrate (18) that are free of connections.

Abstract: Fluid flow indicator is provided in which a fluid pressure to position transducer moves a permanent magnet from a no-flow position to a flow position in response to fluid pressure. The change in the position in the permanent magnet changes the intensity and polarity of the magnetic field that the permanent magnet places upon a Hall effect semiconductor; so that a switching function results as a function of fluid pressure differential causing no-flow and flow conditions. The change in magnitude and polarity of the magnetic field between first and second distances from one surface of the permanent magnet is increased by providing an opening through the permanent magnet and by providing a magnetic device near the opposite surface of the magnet.

Abstract: Parameter sensors and monitors are described incorporating one of a variety of parameter responsive structures constructed and arranged for expansion and contraction causing a component of motion and displacement along at least one direction in response to variations of a selected parameter. A reference mounting supports the parameter responsive structure and either a magnet element or Hall effect transducer is secured relative to the reference mounting or housing in alignment with a selected direction of a component of motion and displacement caused by expansion and contraction of the parameter responsive structure. The other of said magnet element and Hall effect transducer is mounted for relative displacement along said selected direction in response to expansion and contraction of the parameter responsive structure.

Abstract: A magnetic field sensor is disclosed with which the direction of a magnetic field can be determined by using the planar Hall effect. An active layer of the sensor is made of a ferromagnetic amorphous metal which is magnetically isotropic. Thus, the magnetization in the active layer always has the direction of an external magnetic field. The developed planar Hall voltage is a measure of the direction of the magnetic field.

Abstract: A magnetroresistive element formed by laminating a plurality of metallic magnetoresistance effect films having magnetostriction of different signs on a substrate. The magnetoresistive element can be formed to exhibit zero magnetostriction or to exhibit magnetostriction of any desired value. Further, the magnetoresistive element exhibits magnetostriction that changes little with the change in the film composition. The metallic magnetoresistance effect films preferably have positive and negative magnetostriction with an absolute value not greater than 15.times.10.sup.-6.

Abstract: A combination gear-selector, sensor device for use with vehicle transmissions having a plurality of gear positions and certain special gear functions and being controlled by an electronic circuit includes a shift lever having a first, square magnet which, when moved over distinct gear position sensors, indicates selection of a certain gear. A rod coaxially disposed within the shift lever has a second, rectangular magnet, displaced to one side of the first magnet, which when vertically moved over a first function sensor, indicates selection of that function which can be to skip a gear. A coaxial tube surrounds the rod member within the shift lever and has a third, rectangular magnet, displaced to an opposite side of the first magnet, which can be moved over a second function sensor to indicate selection of a second special function.

Abstract: A magnetic axis is imparted to an object which effects three-dimensional rotational movement. The magnetosensitive semiconductor elements are disposed in the directions of three axes or two axes of a space determined for the object in such a manner that the elements are not in contact with the object. Any variation in direction of the magnetic axis resulting from movement of the object is detected by the magnetosensitive semiconductor elements. The detection signals from the magnetosensitive semiconductor elements are electrically processed so that the three-dimensional rotational position and movement of an object may be detected without contact and continuously.

Abstract: A Hall effect probe having output voltage leads arranged across the surface of the probe so as to eliminate the distorting effect of voltages induced in the leads by a varying magnetic field includes in a three lead device, voltage leads connected at opposite corners of a rectangular probe and laid across the surface of the probe at an obtuse angle with respect to the edge so as to define a predetermined surface area. The leads are vertically stacked at an intersection point and extend parallel with one another and with the input current lead until clear of the magnetic field.

Abstract: A Hall effect magnetic field sensing circuit provides an operation amplif which is connected to a signal voltage terminal of the Hall effect sensor with a negative temperature coefficient (TK) of the resistance of the drive current path whose drive current path is provided with an input resistor such that a portion of the Hall effect sensor responds to the change in temperature thereof to vary the drive current and provide temperature compensation of the Hall voltage. A differential amplifier can be provided to eliminate the zero residual voltage effect and a summing circuit connected to the operational amplifier rectifies nonlinearity.

Abstract: A narrow track magnetoresistive transducer has a square shaped bias permanent magnet superposed with an MR element. The square shaped magnet provides bias field components of substantially the same magnitude in both hard and easy axis directions of the MR element. A stable and uniform bias field is thereby obtained.

Abstract: A holder for an electric fuse is provided with a Hall-effect sensor arrangement which is integrally mounted in the fuse holder in close proximity to the current path through the holder. The Hall-effect sensor provides an output voltage responsive to the magnetic field resulting from the flow of current along the current path. The output from the Hall sensor is then processed to provide an indication of whether current is flowing through the fuse holder.

Abstract: A magnetic measuring instrument for measuring the relative position of two objects includes a scanning unit which incorporates a magnet positioned to scan a measuring division. The measuring division is provided with alternately magnetically conducting and magnetically non-conducting zones. Measuring signals of high signal quality are generated because the induction generated by the magnet in the measuring division runs only in planes perpendicular to the longitudinal extent of the measuring division (the measuring direction x). Magnetic field sensitive sensor elements in the air gap between the magnet and the measuring division scan the air gap induction to generate position dependent measuring signals.

Abstract: A remote manual shift control device having a manually operable range selector lever for controlling the operation of solenoids, relays and the like of an electrically controlled transmission, in which the selector lever is mechanically coupled to shift a code slide member to positions corresponding to the range positions, and wherein it coacts with switching components to generate binary coded output signals corresponding to the respective range positions as determined by the shift lever. The control device embodies a unitized sealed electronic module containing an IC Decoder Unit for the binary signals with inhibit and latch control terminals; and a connected Logic and Buffers Unit for determining the proper driving connections with the transmission control devices at the transmission.

Abstract: A differential pressure transmitter includes a housing, a first chamber within the housing for receiving an input pressure to be sensed and a second chamber for receiving a transmitter adapted to generate an electrical signal representative of the input pressure. The chambers are separated by a continuously formed, highly resilient diaphragm. A reaction member embodied as a resilient spring is disposed in the second chamber for sensing a position of the diaphragm resulting from the magnitude of the differential pressure thereacross. The reaction member has a magnetized structure mounted thereon which coacts with a Hall effect transducer embodied in the transmitter for detecting the relative position of the magnetized structure and therefore of the diaphragm and responsively generating an electrical signal. The signal may be utilized for positioning actuator controlled dampers within a VAV system duct.

Abstract: A structure employing the Hall effect for indicating the direction of a magnetic field and comprising a two-ended tubular device of a semi-conductive material and a current generating means for creating, in the absence of a magnetic field, a circumferentially uniformly distributed current flowing between the two ends of the tubular device. A plurality of conductive, wire-like elements extend radially through the tubular device toward the axis thereof and in a common plane normal to such axis and with adjacent ones of the wire-like elements being spaced apart equal angular distances. Calculating logic responds to the relative voltages induced in the wire-like elements when the tubular device is placed in a magnetic field to determine the direction of the magnetic field.

Abstract: A Hall effect device for responding to weak magnetic fields uses a small chip of gallium arsenide located between the overlapped ends of two flux concentrators. The spacing between the concentrators may be as small as 95 micrometers. The flux concentrator, which serve to enhance the device's sensitivity are made of amorphous magnetic material, i.e. a metallic glass, which has high permeability.

Abstract: A magnetoelectric transducer includes a high mobility semiconductor thin film formed on a layer such as an alumina film. Processing to form the device is improved by simultaneous patterning of the semiconductor thin film and an electrode layer. Improved resistance to the effects of heat are obtained by using a highly heat conductive substrate. Integrally with the substrate there may be formed an element such as a series resistor for temperature compensation of the magnetic sensor of the transducer.

Abstract: A pressure switch and transducer arrangement combines into a single unit both a power contact switch for providing power to an automobile fuel pump in response to a predetermined minimum oil pressure and a magnet/Hall effect sensor for providing an analog signal indicative of the oil pressure for use by the automobile on-board microcomputer. The arrangement includes an actuator rod movable by a diaphragm in response to oil pressure. The end of the rod remote from the diaphragm is coupled to a contact washer for providing the power switching function and also to a magnet which cooperates with a fixed Hall effect sensor, which sensor provides an output corresponding to the air gap between the magnet and the sensor. The magnet and the washer are coupled to the actuator rod in such a manner that even after the washer makes contact with the power switching terminals, the actuator rod and magnet are free to continue moving as the oil pressure continues to increase.

Abstract: A magnetoelectric transducer having a substrate of magnetic or non-magnetic material is improved by providing a thin film of crystalline semiconductor In.sub.1-x Ga.sub.x Sb (0<x.ltoreq.0.2) on the substrate either directly or through a metal or semiconductor oxide film.

Abstract: A sensor suitable for measuring magnetic field gradients spanning very small regions has a magnetic field-sensitive element (37, 42) with a very accurately defined height and thickness (even into the nanometer range) which is perpendicular to the surface of a substrate (30, 41) so that the substrate surface may be used in aligning the element (37, 42).

Abstract: Magnetic switch apparatus which includes a casing having a magnetically sensitive component securely positioned therein in a predetermined location. The component may be in the form of either a conventional reed switch or Hall effect sensor and is provided with electrical terminal leads extending therefrom. The casing includes means for locating and securing the leads against movement upon application of a tensile force thereto, such means being in the form of suitable embossments in the casing about which the leads are partially wrapped. The casing further is provided with means for mounting the same on a supporting member, such as a circuit board, in a predetermined position such that the magnetic component will also be correspondingly positioned relative to the supporting member.

Abstract: A device for the pick-up of measured values having a frame forming a first measurement reference and an element movable relatively to the frame and forming a second measurement reference. The device includes a carrier connected to the element forming the second measurement reference and a mechanical/electrical conversion system connected between the frame and the carrier. The conversion system produces a magnetic field directed at right angles to the direction of movement of the carrier and has at least one air gap within which the carrier is arranged to move at right angles to the magnetic field. Two pairs of field plates are arranged in the air gap and when the carrier is moved the extent of penetration of the pairs of the field plates by the magnetic field is changed. The device also includes a bridge circuit by which the field plates are connected. The bridge circuit includes in one diagonal thereof a device for the display of measured values and is connected across the other diagonal thereof to a d.c.

Abstract: Two identical integrated circuit (IC) chips are mounted at a pole of a magnet. Each IC chip includes a Hall-element followed by an amplifier. A comparator is connected to the outputs of the IC chips to produce a voltage that is directly related to the difference between the magnetic field strengths at the two IC chips that may be due to a ferromagnetic article that is closer to one IC chip than the other.

Abstract: In a contactless switch, a magnet is mounted on a rod for movement against the action of a spring to actuate a Hall effect switch. A contactless joy stick switch comprises a rod (20) supported and normally maintained in alignment with an axis (22) by an elastomeric spring (28). A plurality of Hall effect switches (42) are mounted in a circular array around the axis for actuation by a magnet (26) mounted on the rod upon displacement of the rod out of alignment with the axis. A contactless push button switch comprises a magnet (86) supported on a rod (74) which is supported for sliding movement along an axis (78) against the action of a spring (82). Displacement of the magnet (86) actuates a Hall effect switch (94). Another contactless push button switch (100) includes magnets (106, 108) positioned to actuate a Hall effect switch (110) upon sliding movement of a rod (74') against the action of a spring (82').

Abstract: A Hall effect device test circuit which detects Hall effect device operate and release point failures. A magnetic field circuit, a voltage switching circuit, a comparison circuit, a retriggerable monostable multivibrator circuit and a visual indicator circuit are included. The comparison circuit compares the Hall effect device switching voltage to a predetermined threshold and controls the multivibrator circuit which causes a visual pass/fail signal to be provided.

Abstract: For producing readings representative of the position of a fluid-powered actuator, a magnetic position-sensing system is used which is out of contact with the actuator's ram and is completely united with the actuator's cylinder. The sensing system has a periodic magnetic field pattern of the ram itself and a number of magnetic field detectors placed in an end plate of the actuator clear of the ram's outer face. The true position of the ram within one period of the magnetization pattern is measured by electrical interpolation based on output signals of the different magnetic field detectors.

Abstract: A strong magnet is bonded to a conventional Hall element package. A bias current is introduced at one of the output terminals of the Hall element in the direction to cause a reduction in the magnet-bias-induced output voltage. This output voltage is easily reduced by this means to zero. The resulting Hall-element detector is shrouded by a large magnetic biasing field while presenting a low or zero DC output component upon which the signal voltage will be superimposed.

Abstract: Hall effect elements are placed in proximity to magnets in such a way that the position of the magnets relative to the Hall elements is a function of the position of a joystick controller. In this way, the position of the joystick can be "read" by a machine by reference to the Hall effect voltage.

Abstract: An electromagnetic contactor is provided with a flux sensing device, preferably a Hall effect sensor, mounted in its magnetic circuit. The magnetic circuit includes an air gap within which the flux sensing device is mounted. The air gap can be adjusted to control the percent of magnetic flux impinging on the flux sensing device whereby a signal can be taken from the device indicative of the magnitude of flux in the magnetic circuit. The signal can be used to control electrical excitation of the contactor at a predetermined flux level.

Abstract: Magnetic gate, including a magnet having a magnetic pole with an at least partly flat surface, a semiconductor chip having an integrated circuit, a mechanically permeable metal piece, and means attaching the semiconductor chip to the magnetically permeable metal piece for minimizing mechanical stresses acting on the chip to eliminate piezo effects and method of production thereof.

Abstract: A non-contact magnetic potentiometer comprising a rotatably supported first yoke, a second yoke arranged as opposed to the first yoke at a slight spacing, a pair of permanent magnets fixed as inclined on the surface of the first yoke opposed to the second yoke and magnetized in the thickness direction, and a Hall effect device fixed on the second yoke as opposed to the pair of permanent magnets, whereby the structure and manufacture can be simplified and an output voltage of any desired wave form can be obtained. This potentiometer is provided with a means for preventing the influences of the temperature and the variation with the lapse of years.

Abstract: A manually-operated rotary switch apparatus utilizes a rotatable magnet for establishing the dual-polarity outputs of each of a pair of magnetic field sensors, oriented substantially perpendicular to each other. The dual-polarity voltages are processed to approximate the arc tangent of the angle of the knob-rotatable magnetic member, with respect to a reference orientation, to provide digital data output related to the switch position of the manually-rotatable knob.

Abstract: A mold-packaged magnetoelectric transducer element such as a Hall element or a magnetoresistance element comprises a magnetosensitive thin layer, electrodes formed on the thin layer for lead-out connection, an unwindowed film support, leads formed on one surface of the film support, conductive resin for connecting the electrodes and the leads, mold resin packaging on the one surface of the film support the remaining except parts of the leads.

Abstract: Pneumatic suspension system for automotive application in which sprung and unsprung masses are supported by variable volume air spring units and incorporating compressor and exhaust valve devices for supplying an exhausting pressurized air from the units to adjust the height between the masses. A Hall effect device effective across a pressure boundary senses the position of a magnet movable within one of the air spring units and reflects relative movement of the sprung and unsprung masses to effect control of the supply and exhaust of air from the units. By axial movement of the Hall device, dead band width can be established to accommodate normal ride motions between sprung and unsprung components. By rotating the Hall device at any axial position, the vehicle bumper height can be selectively increased or decreased.

Abstract: A Hall effect device comprises a thin substrate free epitaxially grown semiconductor body mounted in a magnetically permeable, e.g. ferrite, housing. The layer, which is preferably gallium arsenide or gallium indium arsenide, is grown on a substrate which, after device processing is complete, is removed by a selective etching process. In view of the relatively high sensitivity and good noise characteristics such a device with its flux concentrator is small, since the flux concentrators are themselves much smaller than with conventional Hall effect systems. Other semiconductor materials from which the novel thin Hall effect devices can be made include silicon.

Abstract: A non-contact magnetic potentiometer comprising a rotatably supported first yoke, a second yoke arranged as opposed to the first yoke at a slight spacing, a pair of permanent magnets fixed as inclined on the surface of the first yoke opposed to the second yoke and magnetized in the thickness direction, and a hall effect device fixed on the second yoke as opposed to the pair of permanent magnets, whereby the structure and manufacture can be simplified and an output voltage of any desired wave form can be obtained. This potentiometer is provided with a means for preventing the influences of the temperature and the variation with the lapse of years.

Abstract: Magnetic gate, including a magnet having two poles, one of the poles having an at least partly flat surfaces, a magnetically permeable metal piece bridging the magnetic flux of the magnet from one to the other of the poles, and a semiconductor chip having an integrated circuit, the semiconductor chip being piezoelectrically unsensitive and being applied to the permeable metal piece, and method of production thereof.

Abstract: A data entry device durable enough to withstand the rigors of industrial type usage in which the electronic components are isolated from the external environment is described. The device comprises a molded elastomer keyboard matrix with thin stainless steel keypads. Embedded into the elastomer beneath the keys are small magnets. Solid state Hall-effect switches are mounted at a predetermined distance from the magnets and are separated from them by a magnetically permeable stainless steel sheet which forms part of the enclosure isolating the electronic components from the environment. Depressing one of the keys on the elastomer matrix moves its associated magnet toward the respective Hall-effect device, causing a change in current which may be sensed by other electronic components. Because of the elastomer material, the keys spring back when released.

Abstract: A control pedal apparatus (10) including a frame member (12), a Hall effect device (52) for generating a control signal responsive to an applied magnetic field, a pedal (14) having a magnet (16) and movable between first and second positions at which a magnetic pathway is opened and closed, respectively, and a movable pedal support (18) for conducting the field between the magnet (16) and the device (52) when the pedal (14) is at the second position.Prior pedal apparatus have wires, connected between the device and an electrical control circuit, to control vehicle direction and which can fail due to flexing, together with a linkage connected to an accelerator portion to control vehicle speed. The pedal support of this invention conducts the magnetic field to a fixed Hall effect device, whereby the wires are eliminated, and the pedal support is movable to generate pulses to control vehicle speed whereby the linkage is eliminated.

Abstract: A liquid level detector "stick" includes a column of Hall-cells adapted to be mounted vertically in a liquid's containing tank. One or more toroidal magnets are slidably fitted about the stick. A float elevates the topmost magnet to the level of liquids in the tank. If the liquids comprise two immiscible parts, a second of the magnets may be floated at the surface of the denser liquid part. A very low power electronic system continuously scans the Hall-cells and determines which particular one or ones of them are adjacent a magnet. This detector may be used in a gasoline station storage tank that may also contain water, providing accurate measure of both liquids. It is also capable of operating in a monitor mode for sounding an alarm when a change in the level of either liquid part occurs that may indicate leakage into or from the tank or an attempted theft.

Abstract: An alarm pull station is provided having a housing for attachment to a support, a manually movable member mounted within the housing and having a magnet attached thereto, and a Hall effect switching device responsive to movement of the magnet for providing an output signal. The Hall effect switching device can include first and second Hall effect sensors arranged for providing three levels of output signal, a first normal level when the manually movable member is in its original, unoperated position, an alarm level when the manually movable member is operated, and a trouble level when the pull station is subject to tampering.

Abstract: In a foot control, two or more pivoted pedals have a common main spring which provides the same resistance to all pedals. A bias arrangement keeps one pedal from falling down if the other pedal is depressed. A bias arrangement may be a horizontal rod associated with each pedal. The rod is spring biased against the pedal at a location below the pivot axis.In a two pedal embodiment both pedals can control a single electrical element. A stud extends from each horizontal rod. The stud normally prevents a spring biased pivoted member from pivoting and actuating the electrical element. When a pedal is depressed, the corresponding rod and stud move to allow the pivoted member to actuate the electric element and a corresponding switch.

Abstract: Two permanent magnets at an adjustably fixed distance from each other face each other with like poles and are mounted on the moveable portion of a pressure-sensitive membrane, with one magnet near the membrane, and the other one at some distance away, while a Hall-effect sensor of fixed position is located between the magnets. The null point of the output scale and the scope of the transducer characteristic can be set either by adjusting the position of the magnets or by adjusting the amount of their magnetization.

Abstract: An electrical switching device for use on machinery to prevent machine operation unless safety guards or the like are correctly positioned comprises two separate parts one part including at least two Hall effect devices which respond to magnetic poles of opposite polarity and electronic switching means which is actuated only when all the Hall effect devices are triggered simultaneously, and the other part including a corresponding number of magnets positioned to actuate the respective Hall effect devices when the two switch parts are placed in close proximity and predetermined orientation. The switch is substantially tamper proof and a control circuit can detect any unauthorized attempt to override the switch.