Telescoping Magnetic Body And Coil Patents (Class 336/136)
  • Patent number: 4943794
    Abstract: A molded coil directly connected face to face to a conductor pattern of a circuit board, for eliminating unnecessary dimensions for pulling out end parts of the coil as face-to-face connection terminals, comprises at least one coil arranged along a vertical direction in which the coil is extending and buried in a synthetic resin body, a lower end part of the coil bent in the resin body in a horizontal direction so as to be orthogonal with the vertical direction and exposed to the outside of the resin body and end parts except the lower end part of the coil exposed to the outside of the resin body parallel to the vertical direction and bent outside in the horizontal direction, to form a face-to-face connection terminal, respectively.
    Type: Grant
    Filed: July 21, 1989
    Date of Patent: July 24, 1990
    Assignee: Toko Kabushiki Kaisha
    Inventors: Masato Suzuki, Tomio Mizutani
  • Patent number: 4926123
    Abstract: A compensation winding for improving the linearity of a displacement transducer. The displacement transducer is the type having an electrically conducting non-ferromagnetic wall which moves in telescoping relation with the coil and is excited by a signal at a sufficiently high frequency that skin effect on the wall permits displacement of the wall to vary the reluctance of the coil flux path and thereby vary its inductance proportionally to displacement of the wall. The compensation winding is wound in telescoped, coaxial relationship to the coil in a fixed position. The compensation winding has a pitch which is a decreasing function of the distance from the end of the coil which is nearest the wall when the wall and the coil are in their least overlapping relationship.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: May 15, 1990
    Assignee: Sunpower, Inc.
    Inventor: Robert W. Redlich
  • Patent number: 4923307
    Abstract: An improved dilatometer suitable for testing the coefficient of thermal expansion (CTE) of a workpiece. The workpiece having a CTE in the range of -0.2.times.10.sup.-6 inch/inch .degree.F. to 0.2.times.10.sup.-6 inch/inch/.degree.F. The improvement includes a reference structure means for positioning and isolating the workpiece, and for maintaining an independent reference temperature, uninfluenced by a required workpiece temperature differential. The temperature independent reference structure means helps assure that measurements of expansions/contractions of the workpiece, as a function of temperature, are uniquely that of the workpiece, and not that of the reference structure means, or any other ambient temperature determinant. The improved dilatometer is particularly useful for determining the CTE of a workpiece having a relatively low value, e.g., a CTE less than 0.1.times.10.sup.-6 inch/inch .degree.F.
    Type: Grant
    Filed: January 24, 1989
    Date of Patent: May 8, 1990
    Assignee: Eastman Kodak Company
    Inventors: James F. Gilmore, Carl A. Lloyd
  • Patent number: 4893078
    Abstract: For enabling a resolver to have absolute position sensing over a wide displacement range while still obtaining the resolution, accuracy and precision obtainable by operation in an incremental mode, the resolver is provided with a number of terminals for providing offset pitch phase indications as a function of position. A microcomputer is programmed to execute a decoding procedure for reading the offset pitch phase indications and from them computing the absolute position. This method is applicable to linear as well as rotary position sensing. By using multiplexing, digital signal processing and large-scale circuit integration of interfacing the resolver to the microcomputer, the method can achieve absolute position sensing with high reliability and low cost. The offset pitch phase indications are readily provided by inductive coupling between a multiplicity of windings, including a set of offset pitch windings connected to the terminals.
    Type: Grant
    Filed: May 28, 1987
    Date of Patent: January 9, 1990
    Inventor: Richard C. Auchterlonie
  • Patent number: 4890084
    Abstract: Side-by-side inductor coils are wound in a single layer around a thin flat tubular frame. The frame has a closed end portion and is mounted on an insulative base sheet. An elongated thin magnetic core is cantilevered from a insulative connecting rod and normally is positioned inside the frame approximately centered between the two coils. The end portion of the connecting rod remote from the frame is secured to the base sheet. The base sheet can be applied to a specimen to be stress tested and is formed to withstand elongation and compression. Lengthwise sliding of movement of the magnetic core in the coil frame due to stress applied to the specimen indicates the strain of the specimen.
    Type: Grant
    Filed: May 12, 1988
    Date of Patent: December 26, 1989
    Assignee: The Institute of Rock & Soil Mechanics Academia Sinica
    Inventor: Li Chu
  • Patent number: 4887465
    Abstract: A screened inductance level transducer has a drive winding for setting up a drive field, and a sense winding in which voltage is induced in the presence of the drive field. A conductive screen, which may be of stainless steel, is mounted on a float for movement in response to liquid level. In the presence of the screen, eddy currents are generated to establish a counter-field opposing the drive field and to thereby shade the sense winding to vary the voltage induced in it. The screen is contained within a tubular barrier which may also be of stainless steel, and the windings are located outside the barrier. In this way, the region within which liquid level is to be measured is isolated from the environment to the exterior of the unit, thus facilitating its use for recording liquid levels in hostile conditions.
    Type: Grant
    Filed: May 14, 1987
    Date of Patent: December 19, 1989
    Assignee: Kollmorgen Corporation
    Inventors: John V. Bryne, Francis McMullin
  • Patent number: 4857824
    Abstract: A two-wire linear transducer comprised of a high permeability finite length core that is positioned with respect to a continuously wound variable pitch coil. The cores is displaced from the initial stroke position at one end of the coil to the opposite end thereof to produce an output signal which varies with displacement. The coil is energized by a constant alternating current source and has a winding configuration that produces an alternating output voltage. The imaginary component of the alternating output voltage varies linearly and continously in amplitude in proportion to the movement of the ferrite core from its initial stroke position to its end stroke position.
    Type: Grant
    Filed: August 29, 1988
    Date of Patent: August 15, 1989
    Assignee: Cadillac Gage Textron Inc.
    Inventor: Sydney K. Tew
  • Patent number: 4853666
    Abstract: A push button for an inductive value input keyboard having a push-button socket, a push-button head guided in the push-button socket, a compression spring which acts between the push-button socket and the push-button head, a stop which limits the stroke of the push button in the non-actuated state, and a rod-shaped iron core fastened to the push-button head for interaction with an induction coil formed by conductor paths upon a printed circuit board on which the push button is arranged. A sleeve is molded at the push-button head and has a non-cylindrical aperture therethrough and is elastically deformable transverse to its axis within which the iron core is clamped.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: August 1, 1989
    Assignee: Mannesmann Kienzle GmbH
    Inventors: Hugo Fesenmeier, Oskar Zumkeller, Werner Schneider, Hans Grieser
  • Patent number: 4841209
    Abstract: A novel actuator control system is characterized by displacement sensor fault detection. The system includes linear variable phase transducer (LVPT) displacement sensors. A pair of engine electronic controls (EEC) each determines the actuator position by measuring the phase shift of the corresponding LVPT output signal with respect to the fixed phase of the LVPT excitation signal. The voltage amplitude of the LVPT output signal has a unique relationship with to the phase of the excitation signal, and is more sensitive to sensor failure than is phase shift alone. A computer in the control compares the amplitude of the LVPT output signal to upper and lower voltage limits for that displacement. Should the computer determine that the voltage amplitude of the secondary winding output signal is out of range, the system will adjust the actuator drive circuits accordingly.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: June 20, 1989
    Assignee: United Technologies Corporation
    Inventor: Demetrius J. Poumakis
  • Patent number: 4808958
    Abstract: A linear variable differential transformer (LVDT), includes a hollow bobbin with first and second ends, a ferromagnetic core adapted for linear movement within the bobbin, a primary coil wound around the exterior of the bobbin, and first and second secondary coils wound around the primary coil. The first and second secondary coils are wound from starting points at the first and second bobbin ends, respectively. The seconardy coils are then wound continuously and simultaneously toward the opposite bobbin ends, so that the two secondary coils cross over each other at a cross-over point approximately halfway between the bobbin ends. The second secondary coil thus overlaps the first secondary coil between the cross-over point and the first bobbin end, and the first secondary coil overlaps the second secondary coil between the cross-over point and the second bobbin end. Each of the secondary coils has a sufficient continuous length to overlay substantially the entire length of the primary coil.
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: February 28, 1989
    Assignee: Bourns Instruments, Inc.
    Inventors: Richard P. Hewitt, Timothy A. Shoemaker, Paul F. Kitlas
  • Patent number: 4736513
    Abstract: A miniature variable inductor comprises a coil soldered to a pair of connecting skids. These skids are clipped to two oppositely disposed lateral walls of an injection-molded plastics cover in the shape of a hollow die. A solid part of the cover and a hollow space lie between these two walls. A central opening through these walls, the solid part of the cover and the hollow space defines a housing for a movable ferromagnetic core. There is a screwthread on at least part of this core. The coil is disposed in the aforementioned hollow space coaxially with the central opening, encapsulated in resin. The central opening has a threaded portion where it passes through the solid part of the cover. This threaded portion is complementary to the thread on the core.
    Type: Grant
    Filed: August 24, 1987
    Date of Patent: April 12, 1988
    Assignee: Acatel
    Inventors: Guy Barbier, Jean-Paul Amory
  • Patent number: 4725805
    Abstract: The construction of cores in an electric-current-controlled type variable inductor used in radio receivers is disclosed. The inductors have three or four cores. In the case of the variable inductors of the type having three cores, the winding portion of a first core is formed with a hollow portion, a second core is inserted into the hollow portion in such a way that the winding portion of the second core can be maintained in parallel with the winding portion of the first core, the first core is inserted into a pot-shaped third core in such a way that the winding portion of the first core can be maintained perpendicular to the bottom of the third core and the magnetic path established by a control coil mounted on the first core and the magnetic path established by a tuning coil mounted on the second core are superimposed one upon another around the winding portion of the second core.
    Type: Grant
    Filed: December 19, 1986
    Date of Patent: February 16, 1988
    Assignee: Toko Kabushiki Kaisha
    Inventor: Noboru Takada
  • Patent number: 4705971
    Abstract: A linear resolver wherein a stator is made of a magnetic material and is toothed at equal pitches along the direction of measurement, and a movable element is an electromagnet made of an E type or C type core around which a primary single phase winding W.sub..theta. is wound, the surface of the movable element facing the stator and constituting part of a magnetic path of the linear resolver being provided with detection secondary windings bonded to the surface, and the detection secondary windings each having as its winding pitch a half the pitch between the teeth of the stator; wherein the movable element is supported relative to the stator with a constant gap therebetween and guided in sliding relation to the stator only in the longitudinal direction of the stator.
    Type: Grant
    Filed: November 8, 1985
    Date of Patent: November 10, 1987
    Assignee: Kabushiki Kaisha Yaskawa Denki Seisakusho
    Inventor: Nagahiko Nagasaka
  • Patent number: 4706058
    Abstract: A miniature variable inductor comprises a coil soldered to a pair of connecting skids. These skids are clipped to two oppositely disposed lateral walls of an injection-moulded plastics cover in the shape of a hollow die. A solid part of the cover and a hollow space lie between these two walls. A central opening through these walls, the solid part of the cover and the hollow space defines a housing for a movable ferromagnetic core. There is a screwthread on at least part of this core. The coil is disposed in the aforementioned hollow space coaxially with the central opening, encapsulated in resin. The central opening has a threaded portion where it passes through the solid part of the cover. This threaded portion is complementary to the thread on the core.
    Type: Grant
    Filed: September 2, 1986
    Date of Patent: November 10, 1987
    Assignee: Alcatel
    Inventors: Guy Barbier, Jean-Paul Amory
  • Patent number: 4694246
    Abstract: The transducer has a primary winding wound around a first cylindrical support which delimits a passage where a core is axially movable, a first secondary winding wound around the primary winding and a second secondary winding wound on a second cylindrical support which surrounds completely the first secondary winding. The first secondary winding is formed in two portions: a regularly wound portion and a stepped portion which are phase connected, and the second secondary winding is formed in two similar portions which are antiphase connected. The output signals of the secondary windings are combined to obtain a differential signal representative of the ratio between the sum and the difference of said signals. The secondary windings are designated so that the ratio cannot reach the value +1 or -1 unless one secondary winding is cut-off, thus conferring to the transducer the capacity of being self-monitored.
    Type: Grant
    Filed: September 19, 1986
    Date of Patent: September 15, 1987
    Assignee: Societe Anonyme: Societe Europeenne de Propulsion
    Inventor: Jean-Bernard Avisse
  • Patent number: 4685678
    Abstract: A joystick position transducer system for use in a video game. The joystick position transducer includes a pair of inductors each having a movable slug, the slugs being coupled to a control handle or knob by means of respective linkages. The control handle or knob is responsive to external stimulus to move the slugs, the inductors providing respective first and second analog signals which are proportional to the position of the slugs. Coupled to each of the inductors is an oscillator and counter for providing a pulsed output, the pulse width of which is proportional to the position of the respective slug. A controller, such as a computer control or logic sequence circuit, is provided to control the oscillators and counters. The controller is further responsive to the counter outputs to control a display presentation on a video display coupled thereto.
    Type: Grant
    Filed: March 19, 1985
    Date of Patent: August 11, 1987
    Assignee: Bally Manufacturing Corporation
    Inventor: Jeffrey E. Frederiksen
  • Patent number: 4680566
    Abstract: The invention concerns a coil arrangement with three windings arranged coaxially, where the outer coils are connected in series. The inductances of the outer coils are of equal magnitude and their magnetic fields have opposing polarities.The center winding induces in the series circuit of the outer windings currents which cancel each other out. The outer windings with their stray inductances form a coil which is separated from the center one and can be applied for other purposes.
    Type: Grant
    Filed: August 15, 1985
    Date of Patent: July 14, 1987
    Assignee: Telefunken Fernseh und Rundfunk GmbH
    Inventors: Walter Goseberg, Alfred Pollack
  • Patent number: 4649337
    Abstract: A phase lag adjustment in an electric meter includes a single-turn loop of large cross section encircling substantially the entire flux generated in a voltage stator which interacts which the disk of the electric meter. A variable inductor, in series with the single-turn loop, changes the effective impedance of the single-turn loop thereby adjusting the phase angle of the flux produced by the voltage stator. The variable inductor consists of a small number of turns of copper having a large cross section within a cylindrical shell made of silicon steel. Threaded bushings at each end of the cylindrical shell accept an adjusting bolt from either direction to permit adjustment from either end of the variable inductor. The silicon-steel cylindrical shell is clamped directly over connecting tabs of the cylindrical shell without insulation therebetween. The high resistance of silicon steel can be ignored in parallel with the much lower resistance of the copper turns.
    Type: Grant
    Filed: March 14, 1985
    Date of Patent: March 10, 1987
    Assignee: General Electric Company
    Inventor: Harold L. Stucker
  • Patent number: 4634126
    Abstract: A transducer converts the amount of mechanical displacement of a member into an electrical signal by magnetic induction. Two fixed coils different in winding direction from each other are spaced apart from each other by a suitable distance and connected in series. Inside the fixed coils, a movable coil is disposed which moves in cooperative association with the member whose amount of movement is to be detected. With the movable coil supplied with an a.c. current, the fixed coils produce an induction current whose amplitude varies with the relative position of the movable coil. A signal processing circuit generates a pulse having a duty ratio corresponding to the amplitude of the induction current. This pulse is converted into a d.c. current in a smoothing circuit to obtain a d.c. voltage corresponding to the amount of mechanical displacement.
    Type: Grant
    Filed: March 26, 1985
    Date of Patent: January 6, 1987
    Assignee: Kabushiki Kaisha Universal
    Inventor: Yutaka Kimura
  • Patent number: 4623840
    Abstract: An actuator has a cylindrical body, on the outer peripheral surface of which an induction coil is formed directly and a piston accommodated in the body and functioning as a core. The displacement of the piston can be detected by a detecting circuit for the change of the coil inductance in response to the displacement of the piston.
    Type: Grant
    Filed: July 5, 1984
    Date of Patent: November 18, 1986
    Assignees: K.K. Tokyo Koki Seizosho, Institute of Science and Engineering Service, Inc.
    Inventors: Tadato Fujimura, Tsutomu Fujii
  • Patent number: 4619288
    Abstract: A lost-motion connection is provided between the armature core of a valve position sensor and the valve plunger preventing relative rotation therebetween while permitting relative axial movement by rotation of an adjuster sleeve having threaded engagement with extensions on both the armature core and valve plunger. Surrounding the adjuster sleeve is a locking collar having a multi-sided internal surface engaging a correspondingly shaped multi-sided exterior surface on the adjuster sleeve, whereby rotation of the locking collar causes rotation of the adjuster sleeve. The locking collar is also axially movable into and out of engagement with another correspondingly shaped multi-sided exterior surface on the valve plunger to respectively prevent and permit rotation of the locking collar relative to the valve plunger.
    Type: Grant
    Filed: November 6, 1985
    Date of Patent: October 28, 1986
    Assignee: Pneumo Corporation
    Inventor: Robert R. McPherson
  • Patent number: 4558295
    Abstract: New ferrite tuning assemblies are disclosed in which a unitary ferrite shaft is covered with a nonmagnetic material to provide a peripheral working surface for coacting with unitary helical thread means in the central opening of a core element to provide axial movement, for air gap adjustment purposes, by cutting and/or deforming at least a portion of the peripheral working surface of the tuning member. Various longitudinal and transverse cross-sectional configurations for the integral male tuning member are made available by the fabrication and assembly methods taught; assembly of inductance-tunable ferrite devices is facilitated by enabling insertion of a male tuning member into the central opening of either core element in an assembly and tuning from either longitudinal end of the aligned central openings.
    Type: Grant
    Filed: November 5, 1982
    Date of Patent: December 10, 1985
    Assignee: Spang & Company
    Inventors: Robert W. Olmsted, Joseph F. Huth, III
  • Patent number: 4548515
    Abstract: Dilatometers are described which employ measuring heads having multiple linear variable differential transformer dilation sensors for concurrently measuring the thermal dilation of multiple specimens within a single conventional electric tube furnace. The sensors, which have their cores coupled to calibrating micrometers, are positioned in a closely separated cluster in which each sensor is parallel, abreast and adjacent to each other. Separate parallel pushrods, which abut separate specimens within a common tubular specimen holder, are attached to the axially mobile coil of each sensor at the point closest to the center of the cluster. The resulting close separation of the parallel pushrods and their specimens within a small diameter specimen holder permits the use of an energy efficient electric tube furnace having a small diameter oriface and facilitates uniform heating of the pushrods and specimens.
    Type: Grant
    Filed: April 23, 1984
    Date of Patent: October 22, 1985
    Inventor: Gerhard R. Clusener
  • Patent number: 4544985
    Abstract: A single or composite lifting electromagnet has several cores whose poles can attract round, elongated or otherwise configurated ferromagnetic objects. The cores are surrounded by and/or flank discrete sensors in the form of Hall generators or induction coils which are provided in addition to exciting coils for the cores. The sensors are disposed centrally of or mirror symmetrically around the center of the electromagnet, and the purpose of the sensors is to generate signals in response to changes of the electromagnetic field to thereby facilitate automatic guidance of the electromagnet toward an optimum position with reference to an object which is to be lifted and transported, e.g., to the treating station of a machine tool.
    Type: Grant
    Filed: March 30, 1983
    Date of Patent: October 1, 1985
    Assignee: EMAG Maschinenfabrik GmbH
    Inventors: Rudi Metz, Herbert Scholl
  • Patent number: 4544905
    Abstract: A linear transducer comprises a former about which is wound a number of windings, the windings being disposed in side by side relationship and having the same number of turns. The windings are connected in series with adjacent windings being wound in the opposite direction. The transducer also includes a core member which has a length substantially equal to the length of the winding. The inductance of the windings varies cylically as the core member is moved through the former.
    Type: Grant
    Filed: November 22, 1983
    Date of Patent: October 1, 1985
    Assignee: Lucas Industries Limited
    Inventors: Christopher H. Best, Alec H. Seilly
  • Patent number: 4542062
    Abstract: A magnetic recording medium comprises a magnetic alloy layer on a substrate wherein said magnetic alloy layer is made of 70-90 wt. % of Co and 30-10 wt. % of at least one of Si, Sb, Li, V, Ta, Ge and Pt and a magnetization axis of said magnetic alloy is substantially vertical to said layer.
    Type: Grant
    Filed: January 20, 2982
    Date of Patent: September 17, 1985
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Kazuo Takada, Seitoku Saito
  • Patent number: 4529956
    Abstract: A pot-core transformer with a magnetic shunt variable to add the function of a variable series inductor independent of the transformer.
    Type: Grant
    Filed: August 16, 1984
    Date of Patent: July 16, 1985
    Assignee: Honeywell Inc.
    Inventor: Jay W. Atherton
  • Patent number: 4523170
    Abstract: New fabricating methods and products are disclosed for manufacture and assembly of tunable-inductance magnetically-soft ferrite core assemblies. Pot core type elements are pressure molded from ferrimagnetic particles having residual reactivity; unitary helical threads are tapped in central openings of compacted core elements while in the green state; subsequent heat treatment converts the green compact to a ceramic. Use of a shrink tap provides compatibility of the unitary threads with the pre-threaded male adjustment members of the prior practice. A new assembly enables use of identical core half sections; provision is made for support at one or both longitudinal ends of the male tuning member.
    Type: Grant
    Filed: November 5, 1982
    Date of Patent: June 11, 1985
    Assignee: Spang & Company
    Inventor: Joseph F. Huth, III
  • Patent number: 4521119
    Abstract: Differential dilatometers are described which employ a linear variable differential transformer dilation sensor in which the core and/or coil is independently supported to accommodate the imposition of a constant load on a specimen abutting a pushrod coupled to that transformer element. The independent support system has at least one collar that slidably enages a mating extension of the supported transformer element, thereby permitting long range axial movement of that element while rigidly restricting lateral movement. The collar which thus holds the supported transformer element may be tilted by an adjustable clamp on at least one plant parallel to the path of axial movement of that element, thereby facilitating alignment adjustment.
    Type: Grant
    Filed: October 3, 1983
    Date of Patent: June 4, 1985
    Assignee: Theta Industries, Inc.
    Inventors: Anthony C. Stepke, Gerhard R. Clusener
  • Patent number: 4512367
    Abstract: A rotation detecting apparatus for a power steering system of a vehicle is described which comprises a control valve coupled to a steering shaft of a steering wheel of the vehicle for controlling a flow of power fluid supplied to a power cylinder for powering a steering operation, a rotator magnet secured on an input shaft of the control valve to rotate therewith as a body, a concentric-circle shaped stator coil adapted to face to the rotor magnet, and a casing functioning also as an iron core yoke mounted on a housing of the control valve for receiving the rotor magnet and the stator coil and supporting the stator coil, whereby, when the input shaft is rotated in response to the steering operation of the steering wheel, an electromotive force is produced so as to detect a displacement in rotation of the input shaft.
    Type: Grant
    Filed: March 7, 1983
    Date of Patent: April 23, 1985
    Assignee: Tokai TRW & Co. Ltd.
    Inventors: Michio Abe, Naoyuki Maeda, Robert M. Lynas
  • Patent number: 4511872
    Abstract: New ferrite pot core type products and fabrication methods are disclosed for production and assembly of tunable-inductance magnetically-soft ferrite devices. Unitary helical threads formed within the central opening of a ferrite pot core element provide controlled axial movement of a non-threaded male tuning member, carrying a ferrite rod, to adjust the air gap between spaced center posts of an assembled pair of pot core elements. Thread matching and registry requirements are eliminated by such unitary thread means which present either helical path die means, for cutting threads in a cylindrical nonmagnetic portion of a male tuning member or, circumferentially continuous helical threads, which deform nonmagnetic protrusions uniformly distributed about the periphery of a noncircular cross section nonmagnetic portion of a male tuning member during rotation of a male tuning member within a core element central opening.
    Type: Grant
    Filed: November 5, 1982
    Date of Patent: April 16, 1985
    Assignee: Spang Industries Inc.
    Inventors: Robert W. Olmsted, Joseph F. Huth, III
  • Patent number: 4510474
    Abstract: A pressure medium-tight inductive pickup for a fluid control element has a pressure pipe composed of a non-magnetic material, a magnetic core received in the pressure pipe, connecting means at the open end of the pressure pipe for pressure-tight connection of the pressure pipe with the control element, a spool body surrounding the pressure pipe, a housing surrounding the spool body and having an axis, and an adjusting element for adjusting zero position of the pickup, wherein the spool body is axially displaceable on the pressure pipe and in the housing, and the adjusting element is formed as a worm drive adjustable from outside and arranged so that the spool body is coupled with the worm drive in a play-free manner in an axial direction.
    Type: Grant
    Filed: June 11, 1982
    Date of Patent: April 9, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Roman Romes, Wolfgang Schilling, Jurgen Werner
  • Patent number: 4502006
    Abstract: An inductive displacement transducer is described in which the magnitude of the phase difference between A.C. current and voltage in a coil is dependent upon the axial displacement of a monitored object. The phase difference depends upon the axial position relative to the coil of a short-circuit turn which moves with the monitored object. A magnetic flux concentrator, which may be combined with the short circuit turn, enhances the flux linkage between the short-circuit turn and the coil. In order to sense the height of a vehicle suspension strut, the coil is mounted on a plastics dirt shield, the short-circuit turn is provided by a sleeve plated with an electrically conductive metal and secured to the strut cylinder. Various circuits are described for monitoring the height signals produced by the different suspension struts of a vehicle.
    Type: Grant
    Filed: October 7, 1983
    Date of Patent: February 26, 1985
    Assignee: Lucas Industries Limited
    Inventors: Alan Goodwin, Malcolm Brearley
  • Patent number: 4498064
    Abstract: A pushbutton tuner wherein tuning coils are disposed in two decks, upper and lower, and the upper or lower tuning coils are disposed in front of the others. A printed circuit board to be connected to said tuning coils by lead wires is divided in two parts and each part is disposed close to the tuning coils in the associated deck.
    Type: Grant
    Filed: November 4, 1982
    Date of Patent: February 5, 1985
    Assignee: Clarion Co., Ltd.
    Inventor: Takao Chaki
  • Patent number: 4460896
    Abstract: An antenna suitable for use in the high frequency (HF) ranges includes a resonator tunable over a predetermined frequency band. The resonator consists of an insulated wire wound over a dielectric rod. Tuning is effected by sliding a metallic sleeve disposed in frictional contact over the wire. A multiplicity of these resonator units may be mounted on a single collar at different angles. Each of the resonator units will respond to a particular frequency. The remaining devices operate as a load on the antenna assembly. The antenna assembly may also be mounted on a conventional mobile antenna by means of an adaptor unit.
    Type: Grant
    Filed: May 17, 1982
    Date of Patent: July 17, 1984
    Inventor: Clarence F. Shmitka
  • Patent number: 4441092
    Abstract: A variable inductor includes a coil, a moveable contactor, and moveable magnetic material caused to move proximate the coil and simultaneously with the contactor. The contactor establishes first and second portions of the coil and, relative to the condition using no magnetic material, the inductance of the first portion is increased while the inductance of the second portion is substantially unchanged. Thus, over substantially all the tuning range, the first portion inductance is maintained greater than the second portion inductance.
    Type: Grant
    Filed: May 3, 1982
    Date of Patent: April 3, 1984
    Assignee: Rockwell International Corporation
    Inventors: Jack C. Thornton, Randy G. Russell
  • Patent number: 4437019
    Abstract: A differential transformer is provided comprising an elongated secondary winding of uniform turn density. First and second transformer primary windings are wound about the secondary winding. The primary windings lie generally in parallel spaced apart planes which cut the axis of the secondary winding at an angle other than 90.degree.. A core of magnetic material is movable linearly along a path parallel to the secondary winding axis and serves to couple the primary and secondary windings. The primary windings are connected to AC sources which are 90.degree. out of phase with each other.
    Type: Grant
    Filed: February 7, 1983
    Date of Patent: March 13, 1984
    Assignee: Pickering & Company, Inc.
    Inventor: Jacob Chass
  • Patent number: 4427961
    Abstract: In a high frequency coil device including a drum core having a lower flange and a shield casing to be securely attached thereto, lugs are provided at the lower ends of a pair of opposing side walls of the shield casing; grooves are formed in a pair of opposing side walls of the lower flange; and the lower ends of those side walls of the shield casing which are provided with the lugs are located at a higher level than the lower ends of the remaining side walls of the shield casing which are provided with no lugs. The lugs are disposed in engagement with the aforementioned grooves and bent into contact with the lower flange. The lower ends of the side walls provided with the lugs are disposed in abutment with the upper surface of the lower flange, and inner surface portions, adjacent to the lower ends, of the side walls provided with no lugs are disposed in engagement with the other opposing side walls of the lower flange.
    Type: Grant
    Filed: September 22, 1982
    Date of Patent: January 24, 1984
    Assignee: Toko, Inc.
    Inventor: Masato Suzuki
  • Patent number: 4413245
    Abstract: An inductive measuring transducer impermeable to pressure media for use with a fluidic adjusting member such as a multiple position valve as a receiving casing of non magnetic working material for receiving a magnetic core, coils surrounding the casing which are, in turn, surrounded by a housing. An operating rod passes into the casing through a connecting member and operates the core. The casing is formed as continuous, hollow cylindrical tube with a closing member or plug inserted in one end and attached in fluid tight relationship. The other end of the receiving casing is tightly connected with the connecting member which is formed as a separate part from the receiving casing.
    Type: Grant
    Filed: August 19, 1981
    Date of Patent: November 1, 1983
    Assignee: Mannesmann Rexroth GmbH
    Inventors: Reiner Bartholomaus, Christoph Gibas, Hans Wolfges, Ferdinand Hess, Karl Schiene
  • Patent number: 4388568
    Abstract: A line end stage for a television receiver which comprises a transformer, a first high voltage rectifier and a second high voltage rectifier. The transformer has a primary winding coupled to the line sweep coils of the receiver, and a secondary winding. The secondary winding has one end coupled through the first high voltage rectifier to ground and through the second high voltage rectifier to the anode of the television receiver picture tube. The transformer comprises a core having a longitudinal axis. The primary winding is mounted on the core coaxial with the longitudinal axis and an insulating winding form surrounds the primary winding. The winding form is provided with spaced longitudinally-distributed radially-extending chambers and the secondary winding is located within these chambers. The thicknesses of the winding form between the bottoms of the chambers and the primary winding are greatest at the ends of the winding form and become progressively smaller toward the center of the form.
    Type: Grant
    Filed: October 31, 1980
    Date of Patent: June 14, 1983
    Assignee: Licentia Patent-Verwaltungs-GmbH
    Inventors: Walter Goseberg, Alfred Pollak, Wolfgang Reichow
  • Patent number: 4347492
    Abstract: A variable inductance transducer for use in engineering metrology comprises a plunger with a tip and carried in a housing in linear bearings with a core mounted on the plunger within the overall axial length of the bearings, so as to produce an axially compact structure. The bearings can be two separate ball bushings with the core disposed between them.
    Type: Grant
    Filed: December 9, 1980
    Date of Patent: August 31, 1982
    Assignee: System E Controls Ltd.
    Inventors: John M. Davis, Barrie C. Burton
  • Patent number: 4347489
    Abstract: A three-phase variable inductor is disclosed in which a fixed frame is formed by a plurality of laminar plates, the plates being rotated with respect to each other about a common axis. Within the frame, a Y network is located, the Y network being so constructed that the magnetic fields generated thereby during operation cancel out in the radial direction to prevent any net radial force from being exerted against a laminar movable reluctor that can be moved into and out of the frame and Y network. As a result of this construction, vibration is eliminated. Both the frame and the movable reluctor are made of iron and silicon, which reduced heat generation and increases efficiency.
    Type: Grant
    Filed: November 12, 1980
    Date of Patent: August 31, 1982
    Inventor: Bruno Bambozzi
  • Patent number: 4339739
    Abstract: A hybrid-coil linear displacement transducer including a base having recesses in which are distributed a primary coil and two secondary coils having a different number of turns, wound scarf-joint fashion, connected in series and in opposition and arranged, at least partially, facing the primary coil, a coupling core moving between the primary and the secondary coils so as to cause the voltages at the terminals of the transformer's secondary coils to vary, wherein the secondary coils consist of two windings made of two wires wound simultaneously, at least one of these two windings being connected in series to a third coil constituting the secondary of an additional transformer of which the primary is connected in series to the primary of the hybrid coil.
    Type: Grant
    Filed: November 5, 1980
    Date of Patent: July 13, 1982
    Assignee: Societe Nationale D'Etude et de Construction de Moteurs D'Aviation, "S.N.E.C.M.A."
    Inventor: Sylvain M. Dron
  • Patent number: 4334207
    Abstract: A linear displacement transducer includes a first elongated magnetizable member having first and second pole pieces which extend parallel with each other over the full length of said first member and which are of substantially constant width along their length. A first winding is wound around part but not all of said first member, a second winding is wound around the full length of the first member. A second elongated member having at least a part which is shorter than said first elongate member is movable linearly relative to the first member in a direction parallel with the longitudinal axis of the first member, such that a substantially constant gap is maintained between the members, to vary the magnetic coupling between the first and second windings when an a.c. signal is applied, in use, to one of the windings.
    Type: Grant
    Filed: June 22, 1979
    Date of Patent: June 8, 1982
    Assignee: Lucas Industries Limited
    Inventors: Colin S. Bill, Charles P. Cockshott, John H. Francis
  • Patent number: 4328475
    Abstract: An improved tuning apparatus for a receiver of the automotive type which includes a tuning core axially slidable within a tubular coil form having an inductance coil wound therearound in which vibratory movement is minimized. The tuning core is formed with a channel at one end to receive one end of an elongated flexible member. The opposite end of the flexbile member extends away from the axis of the tuning core and abuts against the interior surface of the tubular coil form. In this manner, sliding movement between the tuning core and tubular form and wire is permitted during the tuning operation but a resistance to side-to-side (radial) movement of the core is maintained at other times to minimize the effect of mechanical vibrations thereon which give rise to undesirable microphonics on an associated receiver.
    Type: Grant
    Filed: June 2, 1980
    Date of Patent: May 4, 1982
    Assignee: Motorola Inc.
    Inventor: Alfred J. Clark
  • Patent number: 4326236
    Abstract: A control system for providing controllable direct current power for energizing an electromagnetic brake having an alternating current power supply and a power rectifier for converting and supplying direct current power to the brake. A power switch controls the amount of direct current power supplied to the brake. A control circuit controls the actuation of the power switch and includes a brake control actuating a variable output transformer. The output from the transformer is converted to a variable pulse width signal for actuating the power switch. Preferably, the transformer is a variable ratio transformer having a movable core connected to the operator's control. A battery charger and batteries may be connected to the ouput of the power rectifier for maintaining brake power in the event of alternating current line failure. Multiple transistor power switches connected to separate brake coils maintain a portion of brake power in the event of partial equipment failure.
    Type: Grant
    Filed: September 10, 1979
    Date of Patent: April 20, 1982
    Assignee: Baylor Company
    Inventors: Willie L. McNair, Donald L. Lipke, Stanley H. Van Wambeck, Conrad J. Huelsman
  • Patent number: 4319209
    Abstract: A fine tuning coil for use in a local oscillator of a tuner, which is made of a high-tension steel wire or a so-called piano wire. The wire has a diameter which is smaller than that of the conventionally used copper wires, and is loosely wound.
    Type: Grant
    Filed: June 5, 1980
    Date of Patent: March 9, 1982
    Assignee: Alps Electric Co., Ltd.
    Inventor: Toshiwo Hara
  • Patent number: 4307366
    Abstract: A displacement sensor which provides the output electrical signal proportional to the mechanical movement or displacement, without utilizing the mechanical friction. The present displacement sensor comprises of a cylindrical bobbin, a pair of solenoid coils provided on said bobbin with the predetermined spacing between each coils, the length of each of the solenoid coils being the same as that each other, a ferrite core adjustably inserted in said bobbin, a support connected to said ferrite core and an external device the displacement of which is to be sensed, a means for connecting the leads of said coils to external lead lines, and the length of said ferrite core being so defined that the total inductance of the series connected coils is independent from the position of said ferrite core in said bobbin.
    Type: Grant
    Filed: July 26, 1979
    Date of Patent: December 22, 1981
    Assignees: TDK Electronics Co., Ltd., Nippondenso Co., Ltd.
    Inventor: Yutaka Fujita
  • Patent number: 4306208
    Abstract: Mechanical lever controllers, also known as joy-stick type actuators, include a body within which is mounted a rod or lever for pivotal movement. The position of the rod is transmitted by an intermediate coupling or follower member to a differential transformer of the linear voltage differential transducer type (LVDT). The transducer includes an input coil and a pair of oppositely-positioned, axially-aligned output coils, and an armature moves within an armature cavity to vary the inductive coupling between the primary coil and the secondary coils. In one embodiment, two such differential transformers are offset at 90.degree. from each other to provide signals on the "X" and "Y" axes. In another embodiment, single axis output is measured in an actuator having a stackable housing.
    Type: Grant
    Filed: January 10, 1980
    Date of Patent: December 15, 1981
    Assignee: Ledex, Inc.
    Inventor: George T. Coors
  • Patent number: 4297698
    Abstract: A linear variable phase transformer directly converts mechanical displacement information to phase information capable of varying fully over preferably more than a 120.degree. period of a typical AC cycle and up to 360.degree. or more phase variation. Three or more linearly arranged primary windings produce respective AC magnetic fluxes that are phase separated by equal amounts over such full period. A core, which is movably positioned relative to the primary windings, receives and/or combines one or more of such fluxes to produce an output flux that induces in a secondary winding an output AC electrical signal having a phase corresponding to that of the output flux and, thus, the positional relationship of the core and the primary windings. The output AC electrical signal is a time-based signal that can be utilized directly in analog applications or readily demodulated for digital use.
    Type: Grant
    Filed: November 2, 1977
    Date of Patent: October 27, 1981
    Assignee: Pneumo Corporation
    Inventors: Michael A. Pauwels, Abraham L. Poot