US3757262A - Toroidal deflection yoke having conductors wound in flyback manner - Google Patents

Toroidal deflection yoke having conductors wound in flyback manner Download PDF

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Publication number
US3757262A
US3757262A US00229829A US3757262DA US3757262A US 3757262 A US3757262 A US 3757262A US 00229829 A US00229829 A US 00229829A US 3757262D A US3757262D A US 3757262DA US 3757262 A US3757262 A US 3757262A
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United States
Prior art keywords
core
turns
conductor
wound
layer
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Expired - Lifetime
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US00229829A
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English (en)
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D Over
I Thompson
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RCA Licensing Corp
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RCA Corp
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Assigned to RCA LICENSING CORPORATION, TWO INDEPENDENCE WAY, PRINCETON, NJ 08540, A CORP. OF DE reassignment RCA LICENSING CORPORATION, TWO INDEPENDENCE WAY, PRINCETON, NJ 08540, A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: RCA CORPORATION, A CORP. OF DE
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/20—Electromagnets; Actuators including electromagnets without armatures
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F5/00—Coils
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/46—Arrangements of electrodes and associated parts for generating or controlling the ray or beam, e.g. electron-optical arrangement
    • H01J29/70—Arrangements for deflecting ray or beam
    • H01J29/72—Arrangements for deflecting ray or beam along one straight line or along two perpendicular straight lines
    • H01J29/76—Deflecting by magnetic fields only
    • H01J29/764—Deflecting by magnetic fields only using toroidal windings
    • 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
    • H01F41/06—Coil winding
    • H01F41/071—Winding coils of special form
    • H01F2041/0711—Winding saddle or deflection coils

Definitions

  • This invention relates to a toroidal deflection yoke and a method for winding it utilizing conductor turns wound in a flyback manner.
  • toroidal deflection yokes can be used in place of saddle-type deflection yokes in a color television receiver to provide the magnetic fields for causing a plurality of electron beams to scan a raster on the picture tube.
  • Toroidal deflection yokes have an advantage over the saddle-type yokes in that less copper wire is required to produce the required deflection fields.
  • a toroidal deflection yoke including vertical and horizontal deflection coils which have portions thereof interleaved for providing a deflection field with certain characteristics.
  • the particular yoke disclosed in that application also has an asymmetry of coil conductor turns in the four quadrants of the yoke. While the advantages of having interleaved winding precision deflection yokes are recognized, it is equally important for the yoke manufacturer to be able to wind a particular yoke distribution quickly and economically.
  • Another object of the invention is to provide a method for winding the coil of a deflection yoke utilizing conductors wound in a flyback manner to enable continuous winding of overlapping and interleaved portions of a deflection yoke coil.
  • a toroidal deflection yoke in which a multi-layer deflection coil is toroidally wound about a generally cylindrical hollow flared core.
  • the coil conductor is wound over an angular segment of the core for providing a first layer of conductor turns around the small diameter end of the core and to provide a single layer of more widely separated conductor turns around the large diameter end of the core.
  • the conductor is returned along the outside of the core from the end position of the angular segment to a space near the beginning of the segment to form a second layer of turns of the small diameter portion of the core and to fill in, in an interspersed manner, the spaces between the first wound conductor turns at the large diameter end of the core.
  • FIG. 1 is a partial cross-sectional view of a toroidal deflection yoke suitable for embodying the invention
  • FIG. 2 is a partial sectional view looking from the rear to the front of the yoke shown in FIG. 1;
  • FIG. 3 illustrates the placement of the conductor turns in a deflection yoke according to the invention.
  • FIG. 4 shows another embodiment of the placement of conductor turns in a deflection yoke according to the invention.
  • FIG. 1 is a partial cross-sectional view of a toroidal deflection yoke suitable for embodying the invention.
  • a hollow generally cylindrical flared ferrite core 10 includes end caps 11 and 13 of plastic-type material disposed over the small and large diameter ends of the core.
  • the annular end cap 11 includes a plurality of slots 12 to engage the conductor turns to be wound around the core such that as the conductor is drawn taut by the winding machine, the conductor turn will be securely held in place.
  • the annular end cap 13 at the front of the yoke includes a plurality of slots 14 to hold the conductor turns in position at the front of the yoke.
  • a plurality of conductor turns 15 is wound toroidally about the core 10 and the end caps 11 and 13 to form two pairs of horizontal and two pairs of vertical deflection coils.
  • the appropriate end turns of the two pairs of coils are suitably connected to connect the respective coils in series or parallel for being driven by suitable sources of scanning current.
  • FIG. 2 is a partial cross-sectional view looking from the small diameter end to the large diameter end of the yoke shown in FIG. 1.
  • FIG. 2 illustrates how a single layer of conductors 15 at the large diameter end of the core 10 becomes bunched together at the small diameter end to form two layers.
  • the conductors 15 marked with an X" are wound in adjacent slots 12 of the end cap 11 at the small diameter end of the core. These conductor turns fan outwardly from each other as they approach the large diameter end of the core to maintain the same angular spacing between conductors as existed at the small diameter end.
  • the unmarked conductors forming the second layer of conductor turns at the small diameter end are interspersed between the marked conductor turns, the marked and unmarked conductor turns forming a single layer at the large diameter end.
  • FIG. 3 illustrates the placement of conductor turnsin a deflection yoke according to the invention.
  • FIG. 3 serves to illustrate the physical arrangement of the conductors forming vertical and horizontal coils around a portion of the core. Although only two coils are illustrated in FIG. 3, for example, coil 1 may be a horizontal deflection coil and coil 2 may be a vertical deflection coil, it is to be understood that the placement of conductor turns around the remainder of the core is similar to that shown and would form the other pair of deflection coils required to complete the yoke.
  • the numbered circles and the lines connecting them indicate the conductor turns forming a coil 1.
  • the numbered triangles and the lines connecting them indicate the conductor turns forming coil 2.
  • the solid lines connecting the respective circles and triangles represent conductor turns on the outside of the core.
  • the dotted lines connecting the respective circles and triangles represent the conductor turns on the inside of the core.
  • the inside conductor turns represented by the dotted lines are placed adjacent each other and there is no crossing of one conductor over another. This provides a relatively smooth inside surface of the core for providing the desired deflection field and for positioning the yoke closely to the flared glass envelope of the color television picture tube if desired.
  • the first coil is started at the circle I at the rear or small diameter portion of the yoke and the conductor, following the dotted line, is brought along the inside surface of the yoke to a position indicated by circle l at the bottom of the figure, illustrating the front or large diameter portion of the yoke. From this position the conductor is brought along the solid line on the outside of the yoke back to the rear of the yoke to position 2. From this position the wire is again brought on the inside of the yoke adjacent the first turn to position 2 at the front of the yoke and from there back along the outside of the yoke to position 3 at the rear.
  • the first and second turns are wound adajcent each other on both the inside and outside portions of the core.
  • the conductor is wound in a flyback manner to circle 3 at the rear of the yoke, which circle is located between the first and second conductors.
  • the yoke is advanced clockwise from position 1 to position 2 as the wire is brought along the outside of-the core. From position 2 at the front of the yoke, the core is rotated a half position counterclockwise to provide the flyback return conductor on the ouside of the core leading to position 3 at the rear.
  • the two rows of conductor positions at the rear or small diameter end of the core are interleaved.
  • the top one of the two layers at the rear of the core in FIG. 3 represents the outside or second layer of conductors illustrated in FIG. 2.
  • the conductor turn on the outside of the core from circle 15 at the front of the core is advanced several spaces to a position represented by the circle 16 at the rear of the core. This is achieved by advancing the core clockwise the desired number of spaces, while the conductor is beingwound on the outside of the core from the circle 15 at the front to circle 16 at the rear.
  • Coil 2 is wound in a similar manner to coil 1. After going through two conductor turns of coil 2, represented by the numbered triangles 1 and 2 at the left of FIG.3, the core is advanced clockwise to triangle 3 at the rear or small diameter end of the core with the conwinding arrangement enables the two layers of conductors at the rear to be wound at one time, thereby eliminating the requirement of having to first wind the first layer, cutting the wire and going back to wind the second layer in order to complete the coil which occupies at least two layers at the rear of the core.
  • FIG. 4 shows another embodiment of the placement of conductor turns in a deflection yoke according to the invention.
  • the conductor winding distribution on the inside of the core, which portion of conductors produces the required magnetic deflection field is the same as that shown in FIG. 3.
  • the difference between the FIG. 3 and FIG. 4 embodiments is that in FIG. 4 the conductors are not wound in a flyback manner after every second consecutive turn. Rather in FIG. 4 considerably more conductor turns are wound before the flyback winding which fills in the second conductor layer at the rear of the core and the empty spaces between the separated conductors in the single layer at the front of the core.
  • FIG. 4 shows another embodiment of the placement of conductor turns in a deflection yoke according to the invention.
  • coil 1 represented by the numbered circles, is wound sequentially from circle 1 at the rear of the core through circle 7 at the front of the core. From circle 7 al the front the conductor is wound in a flyback manner to circle 8 at the rear of the core as the core is rotated counterclockwise to this position. From circle 8 at the rear, which starts the second layer of conductors at the rear and which will fill in the spaces between the conductor turns at the front of the core, coil 1 continues to be wound clockwise through circle at the front of the core. From circle 15 the core is advanced clockwise as the conductor is wound to circle 16 at the rear of the core. From circle 16 at the rear through circle 27 at the front, coil 1 is wound sequentially and with a flyback to complete the illustrated coil 1 at circle 27 at the front of the core.
  • the core is then rotated counterclockwise back to the left of FIG. 4 so that coil 2, represented by the numbered triangles, may be wound.
  • Two turns of coil 2 are sequentially wound followed by a clockwise advance of the core to triangle 3 at the rear of the core. From triangle 3 at the rear of core coil 2 is sequentially wound through triangle 7 at the front at which time the core is rotated counterclockwise to wind the conductor in a flyback manner to triangle 8 at the rear. From this point the turns are again wound sequentially through triangle 12 at the front of the core which is the end of coil 2.
  • the angular segments of the core over which the coils 1 and 2 extend may comprise as much of the perimeter of the core as desired with the limitation that the core must be reclamped before the entire yoke can be wound.
  • One convenient way of winding a deflection yoke in accordance with the invention is to initially clamp the core in the winding machine, wind all of one horizontal coil and then a part of the second horizontal coil. The extent of the winding of the second horizontal coil is limited by the core clamping mechanism. The core is then reclamped; for example, the clamp is placed degrees around the core from the initial position. The remainder of the second horizontal coil is then wound. Without reclamping at this time, one complete vertical coil is then wound, and a part of the. second.
  • the clamp is then moved back to where it was originally and the remaining portion of the second vertical coil is wound to complete the winding of the yoke.
  • the conductor does not have to be cut between the winding of the first and second horizontal or vertical coils.
  • An extra turn can be wound between the finish of one coil and the start of the other and during the winding cycle or later, when the finished yoke is removed from the winding machine, this extra turn can be cut to form the separate coils. It may be desirable to utilize different color wire for the vertical and horizontal coils, especially if they are interleaved, to make it easy for the operator to properly cut and connect the respective coils.
  • a toroidal deflection yoke comprising:
  • a pair of horizontal and a pair of vertical deflection coils wound toroidally about said core said coils comprising at least two layers of conductor turns at the small diameter portion of said core and a single layer at the large diameter portion of said core;
  • said conductor being wound over an angular segment of said core to occupy successive conductor receiving portions in a first layer around the small diameter portion of said core and to occupy every other conductor receiving portion in said single layer around the large diameter portion of said core, said conductor being returned along the outside of said core from the end position of said angular segment to a space near the beginning of said segment to form a second layer of conductor turns at the small diameter portion of said core and to lie between said first wound conductor turns at the large diameter portion of said core.
  • a toroidal deflection yoke comprising:
  • the conductor turns comprising said coils forming at least first and second layers of turns at the small diameter end of said core and at least a single layer of turns at the large diameter end of said core;
  • the conductor turns forming a first vertical coil portion last turn of said portion of said angular segment I along an angular segment of said core being wound being wound in a flyback manner back to a region over a first portion of said segment occupying adjanear the start of said portion of said angular segcent conductor receiving portions in said first layer ment and wound for forming said second layer of at said small diameter end of said core and occupyturns at said small diameter end of said core and for 10 ing every other conductor receiving portion at said completing said single layer of turns at said large large diameter end of said core, the last turn of said diameter end of said core, said conductor being adportion of said angular segment being wound in a vanced from said first portion of said segment to a flyback manner back to a region near the start of second portion of said angular segment separated said portion of said angular segment and wound for from said first portion for forming a second horiforming said second layer of turns at said small dizon
  • a horizontal coil portion being wound within the separation around said core between said first and second coil portions and having a turns arrangement similar to said first vertical coil portion.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Manufacturing & Machinery (AREA)
  • Formation Of Various Coating Films On Cathode Ray Tubes And Lamps (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Video Image Reproduction Devices For Color Tv Systems (AREA)
US00229829A 1972-02-28 1972-02-28 Toroidal deflection yoke having conductors wound in flyback manner Expired - Lifetime US3757262A (en)

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US22982972A 1972-02-28 1972-02-28

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US (1) US3757262A (it)
JP (1) JPS5737977B2 (it)
AR (1) AR194987A1 (it)
AT (1) AT343727B (it)
BE (1) BE796030A (it)
BR (1) BR7301509D0 (it)
CA (1) CA966543A (it)
DE (1) DE2309581C3 (it)
ES (1) ES412106A1 (it)
FR (1) FR2174026B1 (it)
GB (1) GB1421988A (it)
IT (1) IT979162B (it)
NL (1) NL7302711A (it)
SE (1) SE388719B (it)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3859719A (en) * 1973-11-12 1975-01-14 Gen Instrument Corp Method of making a toroidal core-coil combination with in situ molded end rings
US3875543A (en) * 1973-11-12 1975-04-01 Gen Instrument Corp Toroidal core-coil combination with in situ molded end rings
US3996542A (en) * 1975-04-14 1976-12-07 Rca Corporation Deflection yoke having nonradial winding distribution
US4003012A (en) * 1975-10-09 1977-01-11 General Instrument Corporation Vertical coil for a deflection yoke
US4038621A (en) * 1976-03-16 1977-07-26 Zenith Radio Corporation Precision vertical deflection coil for a hybrid television yoke
US4070640A (en) * 1977-04-07 1978-01-24 Gte Sylvania Incorporated High resolution torodidal deflection yoke
US4128824A (en) * 1977-09-29 1978-12-05 Rca Corporation Multilayered deflection yoke
US4232253A (en) * 1977-12-23 1980-11-04 International Business Machines Corporation Distortion correction in electromagnetic deflection yokes
US4246560A (en) * 1977-09-21 1981-01-20 Hitachi, Ltd. Self-converging deflection yoke
USRE31399E (en) * 1975-10-09 1983-09-27 General Instrument Corp. Vertical coil for a deflection yoke
US4511871A (en) * 1983-07-18 1985-04-16 Rca Corporation Modified deflection yoke coils having shootback windings
US6341759B1 (en) * 1998-12-29 2002-01-29 Robert Bosch Gmbh Electromagnetic actuating valve and method for producing a magnetic casing for a valve

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4934222A (it) * 1972-07-27 1974-03-29
DE2603464C2 (de) * 1976-01-30 1986-10-23 Standard Elektrik Lorenz Ag, 7000 Stuttgart Toroidspulenablenkeinheit
JP2007105778A (ja) * 2005-10-14 2007-04-26 Japan Automat Mach Co Ltd リード線の端末処理装置

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA919243A (en) * 1969-03-07 1973-01-16 Rca Corporation Toroidal electromagnetic deflection yoke

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3859719A (en) * 1973-11-12 1975-01-14 Gen Instrument Corp Method of making a toroidal core-coil combination with in situ molded end rings
US3875543A (en) * 1973-11-12 1975-04-01 Gen Instrument Corp Toroidal core-coil combination with in situ molded end rings
US3996542A (en) * 1975-04-14 1976-12-07 Rca Corporation Deflection yoke having nonradial winding distribution
USRE31399E (en) * 1975-10-09 1983-09-27 General Instrument Corp. Vertical coil for a deflection yoke
US4003012A (en) * 1975-10-09 1977-01-11 General Instrument Corporation Vertical coil for a deflection yoke
US4038621A (en) * 1976-03-16 1977-07-26 Zenith Radio Corporation Precision vertical deflection coil for a hybrid television yoke
US4070640A (en) * 1977-04-07 1978-01-24 Gte Sylvania Incorporated High resolution torodidal deflection yoke
US4246560A (en) * 1977-09-21 1981-01-20 Hitachi, Ltd. Self-converging deflection yoke
US4128824A (en) * 1977-09-29 1978-12-05 Rca Corporation Multilayered deflection yoke
US4232253A (en) * 1977-12-23 1980-11-04 International Business Machines Corporation Distortion correction in electromagnetic deflection yokes
US4511871A (en) * 1983-07-18 1985-04-16 Rca Corporation Modified deflection yoke coils having shootback windings
AU573229B2 (en) * 1983-07-18 1988-06-02 Rca Corp. Modified deflection yoke coils
AT394470B (de) * 1983-07-18 1992-04-10 Rca Licensing Corp Ablenkspulenanordnung und verfahren zu deren herstellung
US6341759B1 (en) * 1998-12-29 2002-01-29 Robert Bosch Gmbh Electromagnetic actuating valve and method for producing a magnetic casing for a valve
US6745457B2 (en) 1998-12-29 2004-06-08 Robert Bosch Gmbh Electromagnetically operable valve and method for producing a magnet housing for a valve

Also Published As

Publication number Publication date
JPS5737977B2 (it) 1982-08-12
ES412106A1 (es) 1976-01-01
DE2309581C3 (de) 1978-08-24
AR194987A1 (es) 1973-08-30
BR7301509D0 (pt) 1974-05-16
CA966543A (en) 1975-04-22
SE388719B (sv) 1976-10-11
GB1421988A (en) 1976-01-21
NL7302711A (it) 1973-08-30
FR2174026B1 (it) 1976-09-10
FR2174026A1 (it) 1973-10-12
IT979162B (it) 1974-09-30
BE796030A (fr) 1973-06-18
AT343727B (de) 1978-06-12
AU5224373A (en) 1974-08-22
DE2309581A1 (de) 1973-09-06
DE2309581B2 (de) 1975-08-14
ATA167873A (de) 1977-10-15
JPS4896228A (it) 1973-12-08

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Owner name: RCA LICENSING CORPORATION, TWO INDEPENDENCE WAY, P

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:RCA CORPORATION, A CORP. OF DE;REEL/FRAME:004993/0131

Effective date: 19871208