Wound Core Patents (Class 336/213)
  • Patent number: 4953286
    Abstract: Strips of cast amorphous metal material are folded to form segments of a transformer core. The segments are arranged in a stack or stacks that will ultimately become a transformer core. A single stack of folded segments is formed about a mandrel into the closed loop of a wound core. Two or more stacks of folded segments are arranged to form the closed loop of a stacked core. The stacks are annealed and the joints opened so that the stacks may be inserted into prewound windings. The joints are then reclosed to complete the transformer core-coil assembly.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: September 4, 1990
    Assignee: Cooper Industries, Inc.
    Inventor: Maurice J. Boenitz
  • Patent number: 4928020
    Abstract: Saturable inductor and transformer for magnetic compression of an electronic pulse, using a continuous electrical conductor looped several times around a tightly packed core of saturable inductor material.
    Type: Grant
    Filed: April 5, 1988
    Date of Patent: May 22, 1990
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Daniel L. Birx, Louis L. Reginato
  • Patent number: 4924201
    Abstract: This amorphous steel core transformer comprises: (i) a coil subassembly having a coil window of generally rectangular cross-section bounded by two end faces and two side faces, at least one of the side faces being slightly concave, and (ii) a core having a leg that fits within the coil window and comprises superposed aligned strips of amorphous steel stacked in the direction of the leg thickness and between said side faces. Each strip has two edges and, disposed between the two edges, a width that approximates the distance between the end faces of the coil window. The strips are further characterized by a slightly greater thickness in their central region than in the region of their edges. The core leg has a thickness that is substantially less in both edge regions of the strips than in the central region of the strips, thus rendering the leg capable of fitting more tightly within said coil window.
    Type: Grant
    Filed: January 13, 1989
    Date of Patent: May 8, 1990
    Assignee: General Electric Company
    Inventor: Donald E. Ballard
  • Patent number: 4922156
    Abstract: A discrete device in which a capacitive and inductive function has been integrated is comprised of at least two insulated amorphous ribbons which are spirally wound to form a cylindrical toroid. Each of the amorphous metal ribbons is insulated from each other ribbon by a dielectric layer and wound in a stacked configuration to provide the capacitive function. Two conductive windings are then wrapped around segments of the cylindrical toroid to provide inductive and/or transforming functions as desired. A magnetic circuit is formed through the windings by the amorphous metal ribbons. A dielectric insulating layer between the ribbons is offset from the longitudinal edge of the ribbon so that the longitudinal edge of each ribbon is exposed. One ribbon has its longitudinal edge exposed on one surface of the toroid while another ribbon has its longitudinal edge exposed on the opposing surface of the toroid.
    Type: Grant
    Filed: April 8, 1988
    Date of Patent: May 1, 1990
    Assignee: ITT Corporation
    Inventors: David E. Turcotte, Waseem A. Roshen, Dale F. Regelman
  • Patent number: 4906960
    Abstract: A distribution transformer and a method of making same. The transformer has at least one closed magnetic circuit in the form of a hollow toroidal coil made from ferro-magnetic steel ribbon. An electric circuit is formed by a primary winding and a secondary winding each constituted by one or more sub-assemblies in the form of a double pancake. These double pancakes are juxtaposed and molded together in a solid insulating material to form a rigid insulating frame on which the magnetic circuit is wound to form one or more magnetic coils. The rigid insulating frame, which is constituted by the primary and secondary windings and the insulating material, also includes therein conduits capable of circulating a cooling fluid through the windings whereby to provide heat exchange to cool the assembly of the electrical and magnetic circuits.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: March 6, 1990
    Assignee: Hydro-Quebec
    Inventor: Nicolai Alexandrov
  • Patent number: 4871925
    Abstract: A high-voltage pulse generating apparatus having at least one magnetic switch comprising a magnetic core constituted by an Fe-base soft magnetic alloy ribbon wound in a toroidal form, the alloy having the composition represented by the general formula: ##STR1## wherein M is Co and/or Ni, M' is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti and Mo, M" is at least one element selected from the group consisting of V, Cr, Mn, Al, elements in the platinum group, Sc, Y, rare earth elements, Au, Zn, Sn and Re, X is at least one element selected from the group consisting of C, Ge, P, Ga, Sb, In, Be and As, and a, x, y, z, .alpha., .beta. and .gamma. respectively satisfy 0.ltoreq.a.ltoreq.0.5, 0.1.ltoreq.x.ltoreq.3, 6.ltoreq.y.ltoreq.25, 3.ltoreq.z.ltoreq.15, 14.ltoreq.y+z.ltoreq.30, 1.ltoreq..alpha..ltoreq.10, 0.ltoreq..beta..ltoreq.10 and 0.ltoreq..gamma..ltoreq.
    Type: Grant
    Filed: October 24, 1988
    Date of Patent: October 3, 1989
    Assignee: Hitachi Metals, Ltd.
    Inventors: Kiyotaka Yamauchi, Yoshihito Yoshizawa, Shin Nakajima
  • Patent number: 4847987
    Abstract: A method of constructing a transformer having an amorphous steel core with a coil about a leg of the core wherein the core leg is formed to a cross-section that more closely conforms to the configuration of the coil window of the coil that surrounds the core leg.
    Type: Grant
    Filed: August 29, 1988
    Date of Patent: July 18, 1989
    Assignee: General Electric Company
    Inventor: Donald E. Ballard
  • Patent number: 4839624
    Abstract: Magnetic cores are manufactured from preforms of magnetically permeable strip material wrapped about non-magnetic supports. The preforms have configurations, such as an X-configuration, that determine the placement and helix angle of convolutions of the strip material that constitute the cores. In a preferred embodiment, corresponding ends of the legs of an X-configuration preform are placed upon a support, and the preform is wrapped about the support so as to form two superposed layers of convolutions, with the convolutions of corresponding portions of the layers having opposite helix angles.
    Type: Grant
    Filed: February 9, 1988
    Date of Patent: June 13, 1989
    Assignee: Schonstedt Instrument Company
    Inventor: Erick O. Schonstedt
  • Patent number: 4839623
    Abstract: Magnetic cores are manufactured from blanks of magnetically permeable sheet material that have core preforms including strip elements that are partially separated from adjacent portions of the blank. Stabilizer strip elements are provided at opposite sides of the preform and are partially separated from adjacent portions of the blank. A tube is attached to one end of the blank and a weight to an opposite end of the blank. After removal of portions of the blank adjacent to the strip elements, the strip elements are wound upon the tube while tension is applied to the strip elements by virtue of the weight. After the winding, the strip elements of the core preform define a core configuration, and the remainder of the blank is removed.
    Type: Grant
    Filed: February 8, 1988
    Date of Patent: June 13, 1989
    Assignee: Schonstedt Instrument Company
    Inventors: Erick O. Schonstedt, Mohammed M. Hamzezadeh
  • Patent number: 4825166
    Abstract: A magnetometer sensor is described for a borehole survey. The magnetometer features a bobbin made from a metal alloy such as copper-nickel, which has a very low magnetic permeability, on the order of 1.0001, which can be joined to a magnetic metal alloy, such as Permalloy, by welding, which can be treated by annealing at a temperature of 1500 degrees Fahrenheit and which has a thermal coefficient of expansion generally on the order of the magnetic alloy. In one particular embodiment, the magnetometer sensor comprises a strip of magnetic metal alloy wrapped around the aforesaid bobbin to define a magnetic core, one excitation winding wrapped around the core, a plastic frame for carrying the magnetic core and excitation winding and at least one sense winding wrapped around the frame, the core and the excitation winding.
    Type: Grant
    Filed: January 27, 1987
    Date of Patent: April 25, 1989
    Assignee: Sundstrand Data Control, Inc.
    Inventor: Douglas C. MacGugan
  • Patent number: 4814736
    Abstract: A transformer core is made by winding a strip of ferromagnetic material, such as amorphous metal or silicon iron, on a winding mandrel to form a first annulus and cutting once through this annulus to create a plurality of individual laminations which are then assembled in packets about a nesting mandrel of a smaller diameter than the winding mandrel to form a second annulus. Each packet consist of a predetermined number of groups of laminations, with the ends of each lamination group lapping each other to form a lap joint. The lap joints of each packet are arranged in staggered positions to create a repeating step-lap joint pattern confined within a predetermined joint region. By decreasing the lap joint dimension and increasing the number of groups in successively assembled packets, the increase in build of the joint region over that of the remainder of the second annulus is minimized. The complete transformer core is uniquely characterized by its variable lap joint dimension and the absence of short sheets.
    Type: Grant
    Filed: February 1, 1988
    Date of Patent: March 21, 1989
    Assignee: General Electric Company
    Inventors: Albert C. Lee, Donald E. Ballard
  • Patent number: 4803773
    Abstract: Magnetic cores are manufactured from preforms of magnetically permeable strip material wrapped about non-magnetic supports. The preforms have configurations, such as an X-configuration, that determine the placement and helix angle of convolutions of the strip material that constitute the cores. In a preferred embodiment, corresponding ends of the legs of an X-configuration preform are placed upon a support, and the preform is wrapped about the support so as to form two superposed layers of convolutions, with the convolutions of corresponding portions of the layers having opposite helix angles.
    Type: Grant
    Filed: August 1, 1986
    Date of Patent: February 14, 1989
    Assignee: Schonstedt Instrument Company
    Inventor: Erick O. Schonstedt
  • Patent number: 4799310
    Abstract: A method of manufacturing a bar antenna having a magnetic core incorporated therein includes removing a covering material from each end portion of parallel covered cords, the parallel covered cords being separated from each other by a length required for winding on the magnetic core, the portions wherefrom the covering material is removed being connected together. A winding start position is set beforehand so that an end portion of the magnetic core can be matched in position with the winding end of a coil. One cord, a connecting portion and the other cord are wound in sequence consecutively from the start position to the end portion of the magnetic core, starting from the base of the separated portions of the cords, so as to form the coil, and thereafter the coil thus formed is transferred to a prescribed position, while the portions of the parallel covered cords not separated from each other are used as an extension cord as they are.
    Type: Grant
    Filed: December 30, 1986
    Date of Patent: January 24, 1989
    Inventors: Atsushi Isobe, Masahiko Isobe, Naoki Isobe
  • Patent number: 4794360
    Abstract: An inductive device comprising a ferromagnetic core which has two approximately U-shaped core halves (9, 11) connected together with their limbs (9', 11'; 9", 11") facing each other so that they enclose a core window (17). Each core half (9, 11) is constructed substantially from a packet of mutually parallel strips of an amorphous ferromagnetic material. Filling members (21', 21") consisting of a solid non-ferromagnetic material are placed between the free ends of each pair of facing limbs (9', 11'; 9", 11"), and in the space (23', 23") between the ends the filling members extend from the core window (17) in the outward direction over at most half of the width of the core limbs. A decrease of the magnetic permeability of the core material as a result of decreasing temperature is compensated by a decrease of the width of the air gaps (23', 23") between the free ends of the limbs (9', 11'; 9", 11").
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: December 27, 1988
    Assignee: U.S. Philips Corporation
    Inventor: Adrianus J. van Mensvoort
  • Patent number: 4789849
    Abstract: This transformer comprises preformed coil structure and a wound core of closed-loop configuration extending about a window and having joints in a localized region thereof that allow the core to be opened at the joints to permit insertion into the window of the preformed coil structure. The core comprises superposed laminations of thin amorphous ferromagnetic strip material which extend around the core from the localized joint region. The laminations include predetermined portions adjacent the joints that are displaced to provide a wide opening into the core window for insertion of the coil structure. A coating of adhesive bonding agent applied before said displacement is present on the lateral edges of the laminations in regions of the core not including said predetermined portions, thereby holding the laminations in correct assembled relationship when the core is opened, yet without interfering with displacement of said predetermined portions.
    Type: Grant
    Filed: January 19, 1988
    Date of Patent: December 6, 1988
    Assignee: General Electric Company
    Inventors: Donald E. Ballard, Willi Klappert
  • Patent number: 4766407
    Abstract: A fixture for defining the window of a jointed magnetic core, which core is constructed of amorphous metal alloy, and methods of constructing such a fixture. The fixture includes first and second substantially U-shaped metallic frame members which are easily and quickly assembled with interlocking joints which positively maintain the desired geometric configuration of the core window, as well as the peripheral dimension thereof. Notwithstanding the high mechanical strength of the fixture, the interlocking joints are easily unlocked, which feature is necessary as the fixture will be required to be assembled, disassembled, and reassembled as part of the normal processing of the magnetic core. New and improved methods of constructing the fixture enable the same tooling to be used for different sizes of fixtures, which are required to cover the range of transformer ratings the magnetic cores will be an integral part of.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: August 23, 1988
    Assignee: Westinghouse Electric Corp.
    Inventor: Frank H. Grimes
  • Patent number: 4761630
    Abstract: An improved transformer core joint for use in connection with amorphous metal transformers which includes a plurality of spirally wound laminations that are divided into a plurality of groups of laminations. The laminations within a group of laminations essentially provide a butt joint within the group while adjacent groups of laminations form a lap joint with each other. The groups of laminations are divided into sets of groups and a step either in the direction of the spiral or against the direction of the spiral occurs between each of the sets of groups. The joint of the invention provides a compact, easily disassembled and reassembled core joint for accommodating the manufacture of amorphous metal transformer cores.
    Type: Grant
    Filed: October 9, 1987
    Date of Patent: August 2, 1988
    Assignee: Westinghouse Electric Corp.
    Inventors: Frank H. Grimes, Eugenius Hammack
  • Patent number: 4747207
    Abstract: Magnetic cores are manufactured from blanks of magnetically permeable sheet material that have core preforms including strip elements that are partially separated from adjacent portions of the blank. Stabilizer strip elements are provided at opposite sides of the preform and are partially separated from adjacent portions of the blank. A tube is attached to one end of the blank and a weight to an opposite end of the blank. After removal of portions of the blank adjacent to the strip elements, the strip elements are wound upon the tube while tension is applied to the strip elements by virtue of the weight. After the winding, the strip elements of the core preform define a core configuration, and the remainder of the blank is removed.
    Type: Grant
    Filed: December 1, 1986
    Date of Patent: May 31, 1988
    Assignee: Schonstedt Instrument Company
    Inventors: Erick O. Schonstedt, Mohammed M. Hamzezadeh
  • Patent number: 4741096
    Abstract: A transformer core is made by winding a strip of ferromagnetic material, such as amorphous metal or silicon iron, on a winding mandrel to form a first annulus and cutting once through this annulus to create a plurality of individual laminations which are then assembled in packets about a nesting mandrel of a smaller diameter than the winding mandrel to form a second annulus. Each packet consist of a predetermined number of groups of laminations, with the ends of each lamination group lapping each other to form a lap joint. The lap joints of each packet are arranged in staggered positions to create a repeating step-lap joint pattern confined within a predetermined joint region. By decreasing the lap joint dimension and increasing the number of groups in successively assembled packets, the increase in build of the joint region over that of the remainder of the second annulus is minimized. The completed transformer core uniquely characterized by its variable lap joint dimension and the absence of short sheets.
    Type: Grant
    Filed: March 13, 1986
    Date of Patent: May 3, 1988
    Assignee: General Electric Company
    Inventors: Albert C. Lee, Donald E. Ballard
  • Patent number: 4707678
    Abstract: A magnetic core containing amorphous metal, suitable for use with electrical inductive apparatus, such as transformers. The desired physical dimensions of the magnetic core are maintained, without adversely stressing the core, by a composite, conformal coating applied to the core edges. The composite coating includes a rigid high strength outer structure and a low stress, adhesive inner structure which cooperatively provide mechanical support and stress protection for the magnetic core, while maintaining its configuration.
    Type: Grant
    Filed: September 22, 1986
    Date of Patent: November 17, 1987
    Assignee: Westinghouse Electric Corp.
    Inventor: Jaime E. Siman
  • Patent number: 4685980
    Abstract: The watt-loss of the Fe-based amorphous alloy-thin strip is decreased by locally melting the surface of thin strip and again vitrifying the melting parts. In addition, the magnetic flux density is enhanced by annealing the thin sheet after the local melting.
    Type: Grant
    Filed: February 12, 1986
    Date of Patent: August 11, 1987
    Assignee: Nippon Steel Corporation
    Inventors: Takashi Sato, Toshio Yamada
  • Patent number: 4670342
    Abstract: A method for making an electrical inductive device for use in hermetic atmospheres which incorporate refrigerants such as halogenated methane compositions, for example refrigerant R-22, monochlorodifluoromethane. The device may be a wound coil device formed of magnet wire, the enamel coating of which has resistance to blistering when exposed to refrigerants under saturated conditions at temperatures up to about 200.degree. or 210.degree. C. and above. The enamel coating composition or wire enamel is formed as the reaction product of 1,2,3,4-butanetetracarboxylic dianhydride, optionally with an aromatic dianhydride, and a diamine such as p,p'-methylenedianiline or p,p'-oxydianiline, in an organic solvent such as N-methyl-2-pyrrolidone.
    Type: Grant
    Filed: April 8, 1985
    Date of Patent: June 2, 1987
    Assignees: General Electric Company, The Valspar Corporation
    Inventors: Marvin A. Peterson, Raymond M. Mooney
  • Patent number: 4646048
    Abstract: To reduce the material in a transformer core and winding assembly, the edges of the core winding legs are relieved so as to achieve improved conformity with the inside corners of the coils disposed thereabout. More intimate spacing of the coils relative to the legs is therefore accommodated with consequent material savings in both the core and the winding coils. Methods for relieving the leg edges by bevelling and notching are disclosed.
    Type: Grant
    Filed: April 29, 1985
    Date of Patent: February 24, 1987
    Assignee: General Electric Company
    Inventors: Robert H. Hunt, Willi Klappert
  • Patent number: 4639705
    Abstract: An electric transformer includes a magnetic circuit and, for each phase, an electrical winding including at least one coil, wherein each electrical winding is made of a good conductive material wire or band, notably aluminum, wound about a wheel rim-shaped annular former. Each magnetic circuit is made of at least one elementary circuit, provided by coiling a magnetic metal strip of constant width, and is formed with a window for the passage of the corresponding winding or windings, has the shape of an irregular polygon with an axis of symmetry. The magnetic circuits are positioned and maintained on a support plate allowing the passage of the windings.
    Type: Grant
    Filed: February 27, 1985
    Date of Patent: January 27, 1987
    Inventor: Jean-Claude Beisser
  • Patent number: 4638554
    Abstract: Each end of an insulating tube which surrounds a transformer core projects beyond the electric circuits carried by the tube and is associated with an annular spacer member having two radially displaced bearing surfaces applied respectively against the core and the tube. An axial slit formed in the insulating tube is opened-out in order to insert a transformer core within the tube and then re-closed. A driving wheel is removably coupled to the tube in order to drive it in rotation during the winding operation.
    Type: Grant
    Filed: August 3, 1984
    Date of Patent: January 27, 1987
    Assignee: Societe Nouvelle Transfix
    Inventor: Jean-Claude Beisser
  • Patent number: 4621248
    Abstract: The present invention relates to a core of magnetic amorphous alloy. A thin strip of such alloy is wound and then cut to provide, e.g., C-shaped pieces. A pair of C-shaped pieces is assembled to provide the core. Conventionally, the magnetic properties, e.g., the watt loss, of the core are impaired at the cut ends of a thin strip due to the formation of burrs.The present invention is characterized by providing the cut ends with a thickness substantially the same as the thickness of the non-cut portion of the thin strip and by polishing the cut ends substantially parallel to the major surface of the thin strip, thereby improving the magnetic properties of the core.
    Type: Grant
    Filed: June 18, 1984
    Date of Patent: November 4, 1986
    Assignee: TDK Corporation
    Inventors: Masao Shigeta, Shotatsu Sugenoya, Tsutomu Cho
  • Patent number: 4616204
    Abstract: The invention provides a method and apparatus for cutting a magnetic core spirally wound from a ribbon of glassy metal. The core is mounted on a mandrel, and a portion of the core is appointed to be cut. A clamping mechanism applies to the outside peripheral surface of said portion, a compressive clamping force directed toward said surface and normal thereto. A positioning mechanism locates and fixes the core and mandrel onto an indexing mechanism. The indexing mechanism moves the core and mandrel to a preselected fixed position, and a cutting mechanism cuts the core.
    Type: Grant
    Filed: June 29, 1984
    Date of Patent: October 7, 1986
    Assignee: Allied Corporation
    Inventors: Hsin L. Li, John D. Misson, David G. Carrigan
  • Patent number: 4615106
    Abstract: A method of consolidating a magnetic core which contains amorphous metal, including the step of thermal spraying an electrically non-conductive material on the edges of the laminations which make up the magnetic core.
    Type: Grant
    Filed: March 26, 1985
    Date of Patent: October 7, 1986
    Assignee: Westinghouse Electric Corp.
    Inventors: Frank H. Grimes, Robert F. Krause
  • Patent number: 4603314
    Abstract: The improved structure of an inductor with an amorphous sheet core and a winding has been found. A core assembly has a pair of housing halves made of non-magnetic material with U-shaped track, in which a laminated amorphous sheet is mounted. The ends of the halves are inserted in a winding so that the ends of the cores abut with each other directly or through a gap spacer. The core halves are pressed by spring action to assemble the inductor. The core halves are produced by the steps of winding an amorphous sheet to a coil, inserting the coil in the track of the housing, and impregnating the coil with plastics.
    Type: Grant
    Filed: October 18, 1983
    Date of Patent: July 29, 1986
    Assignee: TDK Corporation
    Inventors: Kazuo Fukunaga, Minoru Higurashi, Motoyoshi Fujita, Eiichi Suga, Masao Shigeta, Norio Sato
  • Patent number: 4599594
    Abstract: Electrical inductive apparatus, such as a transformer, having a core-coil assembly disposed in a tank. The magnetic core of the core-coil assembly includes amorphous metal, and is of the wound, rectangular, jointless construction. A protective and insulative winding tube is disposed about a winding leg of the magnetic core, and an electrical winding is disposed about the winding tube. The winding tube and tank cooperatively support the weight of the electrical winding.
    Type: Grant
    Filed: February 7, 1985
    Date of Patent: July 8, 1986
    Assignee: Westinghouse Electric Corp.
    Inventor: Jaime E. Siman
  • Patent number: 4588971
    Abstract: The transformer comprises a magnetic circuit (8) as well as, in the case of each phase, a high-voltage electric circuit (17) and a low-voltage electric circuit (18) both wound around at least one section of the magnetic circuit (8).The electric circuits (17, 18) are arranged in at least one electrically insulating annular coil form (11) which, under service conditions, is interposed between the electric circuits (17, 18) and the aforementioned section of the magnetic circuit (8).Utilization in particular for improving the occupation of electric windows by the magnetic circuit and of magnetic windows by the electric circuit.
    Type: Grant
    Filed: August 9, 1983
    Date of Patent: May 13, 1986
    Assignee: Societe Nouvelle Transfix
    Inventor: Jean-Claude Beisser
  • Patent number: 4587507
    Abstract: Conventionally, silicon steel strips and ferrite cores have been used as the core of a choke coil. These strips and the like have not yet been replaced with amorphous alloy because in the known amorphous magnetic alloy the pre-magnetization characteristic, the amount of heat generated, and the secular change are poor.The present invention proposes a core of a choke coil which consists of a coiled thin strip of an amorphous alloy, and has at least one cut air gap, the coiled regions of the thin strip being bound to one another at at least in the neighborhood of said at least one cut air gap, and said amorphous magnetic alloy is essentially comprised of the following composition, Fe.sub.x Mn.sub.y (Si.sub.p B.sub.q P.sub.r C.sub.s).sub.z, wherein x+y+z is 100 atomic % based on all of the elements, y is from 0.001 to 10 atomic %, z is from 21 to 25.5 atomic %, p+q+r+s is atomic % 1, p is from 0.40 to 0.75, r is fro 0.0001 to 0.05, the ratio s/q is from 0.03 to 0.4, and z is z.ltoreq.50p+1, z.ltoreq.10p+19, z.
    Type: Grant
    Filed: November 23, 1982
    Date of Patent: May 6, 1986
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Suguru Takayama, Masao Shigeta
  • Patent number: 4570141
    Abstract: An annular form of magnetic steel comprises a plurality of elongated sheets wound in superposed relationship about a reference axis. The sheets respectively define reference annuli, which are of progressively greater diameter as the annular form is wound about said reference axis. At least one of said reference annuli has a substantially greater diameter at one edge of the annular form than at the opposite edge of the form. At least some of the sheets that are located radially outward of said one reference annulus are provided with thickening means giving these sheets an effective thickness at one side greater than at their other side. Said one side is located on the opposite side of the longitudinal center line of the sheet from said one edge of the annular form.
    Type: Grant
    Filed: July 5, 1984
    Date of Patent: February 11, 1986
    Assignee: General Electric Company
    Inventor: Willi Klappert
  • Patent number: 4558297
    Abstract: The present invention relates to a saturable core which consists of a coiled thin strip of an amorphous magnetic alloy. The present invention provides a saturable core having a high .DELTA.Bs, a low power loss, a good saturation property, and low secular changes of the magnetic properties, due to determining the coiling direction of the saturable core so that it is the same as that of a coil heat treated.
    Type: Grant
    Filed: October 4, 1983
    Date of Patent: December 10, 1985
    Assignee: TDK Corporation
    Inventors: Masao Shigeta, Teruhiko Ojima
  • Patent number: 4529177
    Abstract: The invention provides a method and apparatus for spirally winding a magnetic core from at least one filament of magnetic material. Two congruent mandrel plates are mated together in facing relation to delimit a mandrel having an outer peripheral edge portion. An annular channel is formed in the edge portion to delimit at least one channel region having a preselected characteristic width dimension, and a plurality of graduated templates are optionally disposed about the mandrel edge portion to delimit at least one template region having a preselected characteristic width dimension. Filamentary magnetic material is then wound about the mandrel to fill the channel regions and any template regions, thereby producing the core.
    Type: Grant
    Filed: September 20, 1982
    Date of Patent: July 16, 1985
    Assignee: Allied Corporation
    Inventors: Dilitkumar R. Sheth, Kevin J. Durand
  • Patent number: 4528481
    Abstract: Amorphous magnetic metal alloys are processed by annealing at temperatures sufficient to achieve stress relief and cooling in directed magnetic fields or in zero magnetic fields. The ac and dc properties of magnetic cores produced in accordance with the processes of the invention may be tailored to match those of a wide range of magnetic alloys. Alloys processed in accordance with the invention provide improved performance in inductors, transformers, magnetometers, and electrodeless lamps.
    Type: Grant
    Filed: April 16, 1984
    Date of Patent: July 9, 1985
    Assignee: General Electric Company
    Inventors: Joseph J. Becker, Fred E. Luborsky, Israel S. Jacobs, Richard O. McCary
  • Patent number: 4506248
    Abstract: A stacked magnetic core constructed from amorphous strip material. The legs and yokes of the core include first and second laminations formed from a non-amorphous magnetic strip material. The first and second laminations are spaced from one another to define a gap therebetween. A plurality of laminations formed from an amorphous magnetic strip material is stacked in the gap. Means are provided to join the first and second non-amorphous laminations so as to reinforce and support the core.
    Type: Grant
    Filed: September 19, 1983
    Date of Patent: March 19, 1985
    Assignee: Electric Power Research Institute, Inc.
    Inventor: Kou C. Lin
  • Patent number: 4504813
    Abstract: A wound core transformer is described which features low core losses by the addition of magnetic material in those sides of the wound core which are located outside of the coil. In one embodiment the wound core includes: a base-core is formed from two strips of magnetic material of generally uniform thickness and wrapped about each other in the form of a closed rectangular loop with the ends of each strip offset from each other and the ends of the adjacent strip; and a filler strip of magnetic material which is interleafed between the two strips forming the base-core with its base disposed adjacent the ends of the strips forming the base-core. An electrical conductor is disposed opposite the filler strip and wrapped about the two strips forming the base core so as to form a coil. Under this arrangement, the magnetic induction formed in that side of core containing the base portion of the filler strip is lower than that side of the core around which the coil is wrapped.
    Type: Grant
    Filed: December 3, 1982
    Date of Patent: March 12, 1985
    Assignee: McGraw-Edison Company
    Inventor: Donald P. Strang
  • Patent number: 4368447
    Abstract: A rolled core is formed by winding a thin body of an amorphous magnetic alloy having positive magnetostriction characteristics so that, of the two surfaces the surface of smaller surface coarseness faces inward. This rolled core is improved in iron loss over a rolled core obtained by winding the thin body so that the surface of greater surface coarseness faces inward. Breakage of the thin body tends to occur less frequently when it is wound so that the surface faces inward.
    Type: Grant
    Filed: April 3, 1981
    Date of Patent: January 11, 1983
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Koichiro Inomata, Michio Hasegawa
  • Patent number: 4366520
    Abstract: A plurality of relatively high magnetic permeability strips are interleaved to form layers of a closed loop differential transformer core. Although the material of each layer by itself may have a relatively square hysteresis loop, the core formed of a plurality of interleaved layers of such material has a substantially more rounded hysteresis loop. Such a core can advantageously be used in a ground fault interruption circuit in which power leads pass through a central opening in the core to form a primary winding and a secondary winding wound on the core may have a capacitor connected in circuit therewith to complete a resonant circuit.
    Type: Grant
    Filed: March 25, 1981
    Date of Patent: December 28, 1982
    Assignee: Magnetic Metals Corporation
    Inventors: Guenter B. Finke, Bao-Min Ma
  • Patent number: 4345229
    Abstract: A lamp ballast has a pair of adjacent gapped "O" magnetic cores made of nested, almost complete loops of amorphous metal strip with the gaps in the loops shaped and arranged under the secondary coil to simulate any type of restricted cross section for shaping the lamp current. A long slender reactor has a similar configuration in which the gaps are staggered; a different embodiment has a long central core of compressed amorphous metal flake and a helical overwrap of ribbon. An alloy of iron, boron, and silicon with a high B.sub.r /B.sub.s ratio is preferred for these inductive devices.
    Type: Grant
    Filed: March 2, 1981
    Date of Patent: August 17, 1982
    Assignee: General Electric Company
    Inventors: Robert P. Alley, Russell E. Tompkins
  • Patent number: 4325045
    Abstract: A device for providing closed ring cores with windings. A coil former is rotatably arranged on at least one core leg. Between the coil former and the leg there is provided a guide member which is secured to the leg and which comprises guide paths for the coil former rotatably arranged thereon. The coil former is fixed in position after a coil is wound thereon.
    Type: Grant
    Filed: July 28, 1980
    Date of Patent: April 13, 1982
    Assignee: U.S. Philips Corporation
    Inventor: Siegfried Mehl
  • Patent number: 4262233
    Abstract: Amorphous magnetic metal alloys are processed by annealing at temperatures sufficient to achieve stress relief and cooling in directed magnetic fields or in zero magnetic fields.The ac and dc properties of magnetic cores produced in accordance with the processes of the invention may be tailored to match those of a wide range of magnetic alloys.Alloys processed in accordance with the invention provide improved performance in inductors, transformers, magnetometers, and electrodeless lamps.
    Type: Grant
    Filed: June 2, 1978
    Date of Patent: April 14, 1981
    Assignee: General Electric Company
    Inventors: Joseph J. Becker, Fred E. Luborsky, Israel S. Jacobs, Richard O. McCary
  • Patent number: 4227120
    Abstract: An improved magnetic core of an amorphous metal alloy is provided for electrodeless fluorescent lamps.
    Type: Grant
    Filed: September 22, 1978
    Date of Patent: October 7, 1980
    Assignee: General Electric Company
    Inventor: Fred E. Luborsky
  • Patent number: 4211957
    Abstract: The magnetic core of a lamp ballast is bifilar wound from inherently thin amorphous metal strip and utilizes the laminations of the magnetic circuit as the plates of a capacitor. The outer yoke of the core encases the coils and is edge-wound from amorphous metal ribbon alternated with insulation to also be the power factor capacitor. The inner core is accordion-pleated or spirally wound and is electrically connected to be the starting capacitor. Cutaways in the inner core cause saturation and shape the lamp current waveform.
    Type: Grant
    Filed: January 31, 1979
    Date of Patent: July 8, 1980
    Assignee: General Electric Company
    Inventors: Robert P. Alley, Theodore R. Haller, Russell E. Tompkins
  • Patent number: 4116728
    Abstract: Amorphous magnetic metal alloys are processed by annealing at temperatures sufficient to achieve stress relief and cooling in directed magnetic fields or in zero magnetic fields.The ac and dc properties of magnetic cores produced in accordance with the processes of the invention may be tailored to match those of a wide range of magnetic alloys.Alloys processed in accordance with the invention provide improved performance in inductors, transformers, magnetometers, and electrodeless lamps.
    Type: Grant
    Filed: September 2, 1976
    Date of Patent: September 26, 1978
    Assignee: General Electric Company
    Inventors: Joseph J. Becker, Fred E. Luborsky, Israel S. Jacobs, Richard O. McCary
  • Patent number: 3996086
    Abstract: A method of forming a rectangular laminated frame for an electro-magnetic device such as a solenoid includes forming a rectangular laminated frame. Formation of the frame includes winding a strip of material in spiral fashion to produce a generally annular blank and then subjecting the blank to a forming process. The forming process involves applying to the blank pressure in an outward direction at 4 spaced points on the inner peripheral surface of the blank. This applied to outward pressure deforms the blank to the required shape.
    Type: Grant
    Filed: August 12, 1975
    Date of Patent: December 7, 1976
    Assignee: Expert Industrial Controls Limited
    Inventor: Brian Stanley Worrall
  • Patent number: 3996543
    Abstract: A high voltage current transformer, and method of constructing same, including a primary winding having concentric leads, and a secondary winding on a magnetic core which is inductively linked with the primary winding. The magnetic core is a wound, two part core, with the two core parts being joined by stepped-lap joints. The secondary winding is a distributed winding having turns which are uniformly distributed about the complete magnetic circuit of the magnetic core. The conductor of the secondary winding is severed and the associated ends electrically re-connected, each time the conductor passes a stepped-lap joint.
    Type: Grant
    Filed: February 4, 1976
    Date of Patent: December 7, 1976
    Assignee: Westinghouse Electric Corporation
    Inventors: Edmond E. Conner, James E. Smith