US1889398A - Electrical coil and a method of manufacturing it - Google Patents

Electrical coil and a method of manufacturing it Download PDF

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Publication number
US1889398A
US1889398A US596917A US59691732A US1889398A US 1889398 A US1889398 A US 1889398A US 596917 A US596917 A US 596917A US 59691732 A US59691732 A US 59691732A US 1889398 A US1889398 A US 1889398A
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United States
Prior art keywords
core
windings
inductance
manufacturing
coil
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Expired - Lifetime
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US596917A
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John S Bishop
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AT&T Corp
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Western Electric Co Inc
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Priority to US596917A priority Critical patent/US1889398A/en
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Publication of US1889398A publication Critical patent/US1889398A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/04—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing coils
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49073—Electromagnet, transformer or inductor by assembling coil and core
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49075—Electromagnet, transformer or inductor including permanent magnet or core

Definitions

  • the invention relates to an electrical coil and a method of manufacturing it, and more particularly to an inductance coil havinga toroidal type core and a method of manufacturing it.
  • the objects of the invention are to provide an improved of electrical coil and a method of menu acturing mm 'a definite stable inductance value and-having a definite stable inductance ratio between the two coils in a simple, inexpensive and expeditious manner. 7
  • One of the features of the invention is the use of a small piece of magnetic material, preferably the same. material as used in the core, cemented to one ofthe windings, and/or the adjacent port ion of the core.
  • Fig.1 is a'plan view of a completed inductance toroidal core coil embodying the features of the invention
  • v v Fig. 2 is a side elevation of the embodiment shown in Fig. 1. l.
  • windings 12 and 13 are assembled over the semi-toroid core sections 10 and 11 and are preferably held in the positions desired by means of suitable non-magnetic spacers or wedges 18 and 19 respectively.
  • Thin strips of non-magnetic material 14 and 15, preferably of ceramic material, are suitably secured to the core sections 10 and 11 by means of a non-magnetic eementing material, to secure the core sections 10 and 11 together to provide suitable air gaps 22 and 23 therebetween.
  • a small piece of magnetic material 16 preferably of the same material as the core'sections 10 and 11, is
  • the semi-toroidslO and 11 forming the core of the coil are preferably made in the form of a continuous ring from finely divided magnetic particles formedunder high pressure into a ring in a well known manner and subsequently suitably broken. into two substantially identical circumferential sections or semi-toroids 10 and 11.
  • The-coils 12"" and 13 preferably comprise a number of turns of insulated wire wound on a spool assembly and are preferably secured to their associated ers 18 and 19 respectively.
  • the core sections orsemi-toroids 10 and 11 with the coils 12 and 13 respectively assembled over them, are placed in a suitable fixture such, for-example, as disclosed in U. S. ;Patent 1,748,993 to C. A; Purdy, March 4,
  • the operator instead of removing turns from the winding having the higher inductance, or adding turns to the winding have the lower inductance, applies a small amount of a suitable non-magnetic cement on one end of the winding having the lower inductance and/or on the adjacent portion of the core section.
  • a small iece of magnetic material 16 preferably oi the same material as the core, is placed on the cemented portion of the end of the winding and/or the cemented portion of the core and its position varied, preferably with respect to the center line of the core, until an inductance balance is obtained be tween the two windings.
  • the size of the piece of magnetic material 16 to be used depends upon the amount of unbalance between the two windings and can be readily determined by trying several pieces of different sizes, or by adding material to a piece or removing a portion therefrom.
  • the method of manufacturing electrical coils which consists in forming a core, dividing the core into a plurality of substantially identical sections, placin windings thereon in sections, assembling t e core sections in spaced relation, varying the space between the core sections until a definite predetermined effect is obtained in the coil, and adjusting the position of a piece of a magnetic material ad acent one of said windings until a definite predetermined efiect is obtained in said one winding.
  • a magnetic coil comprising a broken annular core, a pair of windings mounted one upon each section of the core, means for securing the parts of the core with a suitable air gap therebetween, and means comprising a piece of magnetic material secured adjacent one of said windings for obtaining an inductance balance between said windings.
  • a magnetic coil comprising a core, a pair of windings mounted upon different portions of said core, and means for adjusting the inductance of one of said windings without appreciably efi'ecting the inductance of theiother of said windings comprising a piece of magnetic material secured adjacent said his; mentioned winding.
  • an electric coil comprising breaking an annular magnetic core, mounting a pair of windings having approximately the same number of turns on the coregjoining the parts of the as to form a smallair gap therebeee ad usting the position of a "piece of maguring the windings-to the core and

Description

Nov. 29, 1932 1,889,398
ELECTRICAL COIL AND A METHOD OF MANUFACTURING IT Filed March 5, 1932 INVENTOR J. S. BISHOP ATTORNEY Patented Nov. 29, 1932 UNITED STATES PATENT OFFICE JOHN S. BISHOP, OF CRANFORD, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC COM- PANY, INCORPORATED, OF NEW YORK, N. 'Y., A CORPORATION OF NEW YORK ELECTRICAL COIL AND A METHOD OF MANUFACTURING IT Application filed March 5, 1932. Serial no. 596,917.
The invention relates to an electrical coil and a method of manufacturing it, and more particularly to an inductance coil havinga toroidal type core and a method of manufacturing it.
One type of an inductance toroidal core coil which is used in. connection with teleriations in the permeability of the cores and uncontrollable distribution of the wire in the windings even though the exact number of turns of wire are wound thereon, which in the subsequent inductance adjustment of the coil may require the removal of a portion of the wire or in some cases the addition of turns of wire. I
"The objects of the invention are to provide an improved of electrical coil and a method of menu acturing mm 'a definite stable inductance value and-having a definite stable inductance ratio between the two coils in a simple, inexpensive and expeditious manner. 7
One of the features of the invention is the use of a small piece of magnetic material, preferably the same. material as used in the core, cemented to one ofthe windings, and/or the adjacent port ion of the core.
The invention may be better understood by reference to the following description and accompanying drawing in which Fig.1 is a'plan view of a completed inductance toroidal core coil embodying the features of the invention, and v v Fig. 2 is a side elevation of the embodiment shown in Fig. 1. l.
Referring to the drawing, windings 12 and 13 are assembled over the semi-toroid core sections 10 and 11 and are preferably held in the positions desired by means of suitable non-magnetic spacers or wedges 18 and 19 respectively. Thin strips of non-magnetic material 14 and 15, preferably of ceramic material, are suitably secured to the core sections 10 and 11 by means of a non-magnetic eementing material, to secure the core sections 10 and 11 together to provide suitable air gaps 22 and 23 therebetween. A small piece of magnetic material 16, preferably of the same material as the core'sections 10 and 11, is
suitably secured to one of the windings 13 and/or to the adjacent portion of the core section 11 by means of a non-magnetic cementing material.
The referred procedure in manufacturing coils 0 this type is as follows:
The semi-toroidslO and 11 forming the core of the coil are preferably made in the form of a continuous ring from finely divided magnetic particles formedunder high pressure into a ring in a well known manner and subsequently suitably broken. into two substantially identical circumferential sections or semi-toroids 10 and 11.
Upon the semi-toroids 10 and 11 are mount- I ed coils 12 and 13 respectively. The-coils 12"" and 13 preferably comprise a number of turns of insulated wire wound on a spool assembly and are preferably secured to their associated ers 18 and 19 respectively.
The core sections orsemi-toroids 10 and 11 with the coils 12 and 13 respectively assembled over them, are placed in a suitable fixture such, for-example, as disclosed in U. S. ;Patent 1,748,993 to C. A; Purdy, March 4,
1930. The thin strips of non-magnetic material .14 and.'15 are secured to the semitoroids 10 and Hover the ends of the air gaps 22. and 23 by means of a suitable nonmagnetic cement; The use ,of thin strips-of ceramic material 14 and 15 to secure the core sections 10 and 11 together, which forms no part of this application, is disclosed and claimed in a copending application of H5 Schwartzmann, Serial No. 596,918, filed March 5, 1932. h
,.After. the cement between the thin strips semi-toroi of non-magetic material 14 and 15 and the 10 and 11 has hardened the coil core sectlons by means of non-magnetic spac- Q is connected to a test set of any suitable type well known in the art to determine the inductance unbalance between the two coils.
If there is an unbalance between the two coils the operator determines which of the coils has the lower inductance.-
In accordance with the invention the operator, instead of removing turns from the winding having the higher inductance, or adding turns to the winding have the lower inductance, applies a small amount of a suitable non-magnetic cement on one end of the winding having the lower inductance and/or on the adjacent portion of the core section. A small iece of magnetic material 16, preferably oi the same material as the core, is placed on the cemented portion of the end of the winding and/or the cemented portion of the core and its position varied, preferably with respect to the center line of the core, until an inductance balance is obtained be tween the two windings. The size of the piece of magnetic material 16 to be used depends upon the amount of unbalance between the two windings and can be readily determined by trying several pieces of different sizes, or by adding material to a piece or removing a portion therefrom.
The invention is also capable of other mod- I ifications and adaptations not specifically referred to but included within the scope of the appended claims.
What is claimed is:
l. The method of manufacturing electrical coils which consists in forming a core, dividing the core into a plurality of substantially identical sections, placin windings thereon in sections, assembling t e core sections in spaced relation, varying the space between the core sections until a definite predetermined effect is obtained in the coil, and adjusting the position of a piece of a magnetic material ad acent one of said windings until a definite predetermined efiect is obtained in said one winding.
2. The method of manufacturing an electrical coil comprising breaking an annular core, mounting a plurality of divided windings on the core, joining the parts of the core .50 as to form a small air gap therebetween,
netic material adjacent the winding having the lower inductance until an inductance bal ance between the two windings is obtained.
d. A magnetic coil comprising a broken annular core, a pair of windings mounted one upon each section of the core, means for securing the parts of the core with a suitable air gap therebetween, and means comprising a piece of magnetic material secured adjacent one of said windings for obtaining an inductance balance between said windings.
5. A magnetic coil comprising a core, a pair of windings mounted upon different portions of said core, and means for adjusting the inductance of one of said windings without appreciably efi'ecting the inductance of theiother of said windings comprising a piece of magnetic material secured adjacent said his; mentioned winding.
In witness whereof, I hereunto subscribe my name this 23rd day of February, 1932.
, JOHN S. BISHOR,
adjusting the windings upon the core with- V relation to the joints between the parts of the core, securing the windings to the core and Q I adjusting the position of a piece of magnetic material adjacent one of said windings until predetermined electrical properties are obtained. A
3. The method of manufacturing, an electric coil comprising breaking an annular magnetic core, mounting a pair of windings having approximately the same number of turns on the coregjoining the parts of the as to form a smallair gap therebeee ad usting the position of a "piece of maguring the windings-to the core and
US596917A 1932-03-05 1932-03-05 Electrical coil and a method of manufacturing it Expired - Lifetime US1889398A (en)

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Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2920307A (en) * 1954-07-19 1960-01-05 Jersey Prod Res Co Variable gap reluctance transducer
US4637803A (en) * 1984-02-21 1987-01-20 Videocolor Process for positioning and grasping semi ferrites for a magnetic core and centering device for operating said process
US4782582A (en) * 1984-12-13 1988-11-08 Eastrock Technology Inc. Process for the manufacture of a toroidal ballast choke
US20060096088A1 (en) * 2004-11-10 2006-05-11 Lotfi Ashraf W Method of manufacturing an encapsulated package for a magnetic device
US20070075817A1 (en) * 2005-10-05 2007-04-05 Lotfi Ashraf W Magnetic device having a conductive clip
US20080301929A1 (en) * 2004-11-10 2008-12-11 Lotfi Ashraf W Method of Manufacturing a Power Module
US20090066300A1 (en) * 2007-09-10 2009-03-12 Lotfi Ashraf W Power Converter Employing a Micromagnetic Device
US7920042B2 (en) 2007-09-10 2011-04-05 Enpirion, Inc. Micromagnetic device and method of forming the same
US20110101948A1 (en) * 2008-04-16 2011-05-05 Douglas Dean Lopata Power Converter with Controller Operable in Selected Modes of Operation
US20110101949A1 (en) * 2008-04-16 2011-05-05 Douglas Dean Lopata Power Converter with Controller Operable in Selected Modes of Operation
US7952459B2 (en) 2007-09-10 2011-05-31 Enpirion, Inc. Micromagnetic device and method of forming the same
US7955868B2 (en) 2007-09-10 2011-06-07 Enpirion, Inc. Method of forming a micromagnetic device
US8018315B2 (en) 2007-09-10 2011-09-13 Enpirion, Inc. Power converter employing a micromagnetic device
US8133529B2 (en) 2007-09-10 2012-03-13 Enpirion, Inc. Method of forming a micromagnetic device
US8139362B2 (en) 2005-10-05 2012-03-20 Enpirion, Inc. Power module with a magnetic device having a conductive clip
US8153473B2 (en) 2008-10-02 2012-04-10 Empirion, Inc. Module having a stacked passive element and method of forming the same
US8266793B2 (en) 2008-10-02 2012-09-18 Enpirion, Inc. Module having a stacked magnetic device and semiconductor device and method of forming the same
US8339802B2 (en) 2008-10-02 2012-12-25 Enpirion, Inc. Module having a stacked magnetic device and semiconductor device and method of forming the same
US8541991B2 (en) 2008-04-16 2013-09-24 Enpirion, Inc. Power converter with controller operable in selected modes of operation
US8631560B2 (en) * 2005-10-05 2014-01-21 Enpirion, Inc. Method of forming a magnetic device having a conductive clip
US8692532B2 (en) 2008-04-16 2014-04-08 Enpirion, Inc. Power converter with controller operable in selected modes of operation
US8698463B2 (en) 2008-12-29 2014-04-15 Enpirion, Inc. Power converter with a dynamically configurable controller based on a power conversion mode
US8701272B2 (en) 2005-10-05 2014-04-22 Enpirion, Inc. Method of forming a power module with a magnetic device having a conductive clip
US8867295B2 (en) 2010-12-17 2014-10-21 Enpirion, Inc. Power converter for a memory module
US9054086B2 (en) 2008-10-02 2015-06-09 Enpirion, Inc. Module having a stacked passive element and method of forming the same
US9509217B2 (en) 2015-04-20 2016-11-29 Altera Corporation Asymmetric power flow controller for a power converter and method of operating the same
US9548714B2 (en) 2008-12-29 2017-01-17 Altera Corporation Power converter with a dynamically configurable controller and output filter

Cited By (41)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2920307A (en) * 1954-07-19 1960-01-05 Jersey Prod Res Co Variable gap reluctance transducer
US4637803A (en) * 1984-02-21 1987-01-20 Videocolor Process for positioning and grasping semi ferrites for a magnetic core and centering device for operating said process
US4782582A (en) * 1984-12-13 1988-11-08 Eastrock Technology Inc. Process for the manufacture of a toroidal ballast choke
US20080301929A1 (en) * 2004-11-10 2008-12-11 Lotfi Ashraf W Method of Manufacturing a Power Module
US7462317B2 (en) 2004-11-10 2008-12-09 Enpirion, Inc. Method of manufacturing an encapsulated package for a magnetic device
US8043544B2 (en) 2004-11-10 2011-10-25 Enpirion, Inc. Method of manufacturing an encapsulated package for a magnetic device
US8528190B2 (en) 2004-11-10 2013-09-10 Enpirion, Inc. Method of manufacturing a power module
US20060096088A1 (en) * 2004-11-10 2006-05-11 Lotfi Ashraf W Method of manufacturing an encapsulated package for a magnetic device
US20070075817A1 (en) * 2005-10-05 2007-04-05 Lotfi Ashraf W Magnetic device having a conductive clip
US8631560B2 (en) * 2005-10-05 2014-01-21 Enpirion, Inc. Method of forming a magnetic device having a conductive clip
US7688172B2 (en) 2005-10-05 2010-03-30 Enpirion, Inc. Magnetic device having a conductive clip
US8384506B2 (en) 2005-10-05 2013-02-26 Enpirion, Inc. Magnetic device having a conductive clip
US10304615B2 (en) 2005-10-05 2019-05-28 Enpirion, Inc. Method of forming a power module with a magnetic device having a conductive clip
US8139362B2 (en) 2005-10-05 2012-03-20 Enpirion, Inc. Power module with a magnetic device having a conductive clip
US8701272B2 (en) 2005-10-05 2014-04-22 Enpirion, Inc. Method of forming a power module with a magnetic device having a conductive clip
US7955868B2 (en) 2007-09-10 2011-06-07 Enpirion, Inc. Method of forming a micromagnetic device
US8618900B2 (en) 2007-09-10 2013-12-31 Enpirion, Inc. Micromagnetic device and method of forming the same
US8133529B2 (en) 2007-09-10 2012-03-13 Enpirion, Inc. Method of forming a micromagnetic device
US7952459B2 (en) 2007-09-10 2011-05-31 Enpirion, Inc. Micromagnetic device and method of forming the same
US8018315B2 (en) 2007-09-10 2011-09-13 Enpirion, Inc. Power converter employing a micromagnetic device
US20090066300A1 (en) * 2007-09-10 2009-03-12 Lotfi Ashraf W Power Converter Employing a Micromagnetic Device
US9299489B2 (en) 2007-09-10 2016-03-29 Enpirion, Inc. Micromagnetic device and method of forming the same
US8339232B2 (en) 2007-09-10 2012-12-25 Enpirion, Inc. Micromagnetic device and method of forming the same
US7920042B2 (en) 2007-09-10 2011-04-05 Enpirion, Inc. Micromagnetic device and method of forming the same
US7544995B2 (en) 2007-09-10 2009-06-09 Enpirion, Inc. Power converter employing a micromagnetic device
US20110101949A1 (en) * 2008-04-16 2011-05-05 Douglas Dean Lopata Power Converter with Controller Operable in Selected Modes of Operation
US8541991B2 (en) 2008-04-16 2013-09-24 Enpirion, Inc. Power converter with controller operable in selected modes of operation
US20110101948A1 (en) * 2008-04-16 2011-05-05 Douglas Dean Lopata Power Converter with Controller Operable in Selected Modes of Operation
US8686698B2 (en) 2008-04-16 2014-04-01 Enpirion, Inc. Power converter with controller operable in selected modes of operation
US8692532B2 (en) 2008-04-16 2014-04-08 Enpirion, Inc. Power converter with controller operable in selected modes of operation
US9246390B2 (en) 2008-04-16 2016-01-26 Enpirion, Inc. Power converter with controller operable in selected modes of operation
US8266793B2 (en) 2008-10-02 2012-09-18 Enpirion, Inc. Module having a stacked magnetic device and semiconductor device and method of forming the same
US9054086B2 (en) 2008-10-02 2015-06-09 Enpirion, Inc. Module having a stacked passive element and method of forming the same
US8339802B2 (en) 2008-10-02 2012-12-25 Enpirion, Inc. Module having a stacked magnetic device and semiconductor device and method of forming the same
US8153473B2 (en) 2008-10-02 2012-04-10 Empirion, Inc. Module having a stacked passive element and method of forming the same
US8698463B2 (en) 2008-12-29 2014-04-15 Enpirion, Inc. Power converter with a dynamically configurable controller based on a power conversion mode
US9548714B2 (en) 2008-12-29 2017-01-17 Altera Corporation Power converter with a dynamically configurable controller and output filter
US8867295B2 (en) 2010-12-17 2014-10-21 Enpirion, Inc. Power converter for a memory module
US9627028B2 (en) 2010-12-17 2017-04-18 Enpirion, Inc. Power converter for a memory module
US9509217B2 (en) 2015-04-20 2016-11-29 Altera Corporation Asymmetric power flow controller for a power converter and method of operating the same
US10084380B2 (en) 2015-04-20 2018-09-25 Altera Corporation Asymmetric power flow controller for a power converter and method of operating the same

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