US3662307A - Flyback transformer - Google Patents

Flyback transformer Download PDF

Info

Publication number
US3662307A
US3662307A US883806A US3662307DA US3662307A US 3662307 A US3662307 A US 3662307A US 883806 A US883806 A US 883806A US 3662307D A US3662307D A US 3662307DA US 3662307 A US3662307 A US 3662307A
Authority
US
United States
Prior art keywords
temperature
ferrite
flyback transformer
high voltage
core
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US883806A
Other languages
English (en)
Inventor
Teruhiro Tsukuda
Takashi Tsutsumi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP5900869U external-priority patent/JPS4837774Y1/ja
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Application granted granted Critical
Publication of US3662307A publication Critical patent/US3662307A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/42—Flyback transformers
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F3/00—Non-retroactive systems for regulating electric variables by using an uncontrolled element, or an uncontrolled combination of elements, such element or such combination having self-regulating properties
    • G05F3/02—Regulating voltage or current
    • G05F3/04—Regulating voltage or current wherein the variable is AC
    • G05F3/06—Regulating voltage or current wherein the variable is AC using combinations of saturated and unsaturated inductive devices, e.g. combined with resonant circuit
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/008—Details of transformers or inductances, in general with temperature compensation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/42—Flyback transformers
    • H01F2038/426—Flyback transformers with gap in transformer core

Definitions

  • FLYBACK TRANSFORMER [72] Inventors: Teruhiro Tsukuda, Moriguchi-shi; Takashi Tsutsumi, Suita-shi, both of Japan Matsushita Electric Co., Ltd., Osaka, Japan [22] Filed: Dec. 10, 1969 [21] Appl.No.: 883,806
  • ABSTRACT Temperature increase becomes a problem with a flyback transformer of a television receiver since it handles a high voltage. In order to cope with this, it has conventionally been the usual practice to make the core gap sufficiently great to provide allowance for the design. With such a construction, however, the transformer becomes large in size, and the highvoltage stability thereof is deteriorated.
  • a temperature-sensitive ferrite is provided in the gap of the core to prevent the slope of the B-H curve from becoming unduly small and to stabilize the high voltage during normal operation.
  • the Curie point of this temperature-sensitive ferrite is utilized to improve the temperature stability of the flyback transformer.
  • This invention relates to a flyback transformer for television receivers which is adapted to provide a high voltage that is stabilized with respect to temperature variations.
  • the high acceleration voltage imparted to the picture tube is taken from the flyback transformer, but temperature rise becomes a problem with the flyback transfonner since the latter handles high power.
  • a large temperature rise can occur especially if the AC input voltage becomes excessive or the horizontal oscillator frequency is deviated so as to be lower than 15.75 KC.
  • a color television receiver which consumes high power requires a large-sized flyback transformer in the horizontal deflection output portion thereof, wherein since high power is handled, it is essential to stabilize the high voltage so as to minimize variations in the picture amplitude, beam convergence peculiar to shadow-mask type picture tubes, white balance, color purity and so forth.
  • This high voltage is as high as about KV, and yet a capacity of 1 mA is required.
  • FIG. 1 shows the construction of a common flyback transformer, wherein numeral 1 represents a ferrite core, 2 a gap, 3 a primary coil, and 4 a high voltage coil.
  • numeral 1 represents a ferrite core, 2 a gap, 3 a primary coil, and 4 a high voltage coil.
  • the gap 2 is made so great that even if a load is increased, the operating point may be located in the straight portion of a 8-H curve. This is to prevent the temperature of the core from being increased due to an increase of the high voltage which results from the fact that when the transformer is operated in the neighborhood of the saturation point, is decreased by an increase of the load. With such an arrangement, however, the efficiency becomes low in the normal operating temperature range. (The permeability of the magnetic circuit is low.) Furthermore, in order to achieve a predetermined inductance, a great number of turns is required which makes the transformer'bulky.
  • the present invention is intended to eliminate the aforementioned drawbacks.
  • Another object of the present invention is to provide a flyback transformer which is stabilized with respect to temperature rise in the case of anomalous operation of the television receiver.
  • Still another object of the present invention is to provide a flyback transformer wherein a temperature-sensitive ferrite can be easily and rigidly mounted.
  • FIG. 1 is a view showing a conventional flyback transformer
  • FIG. 2 is a view showing B-I-I curves thereof
  • FIG. 3 is a view showing the relationship between the gap of the core and the internal resistance of the flyback transformer (the lower the internal resistance, the higher the stability);
  • FIG. 4 is a side view showing the flyback transformer according to an embodiment of the present invention.
  • FIG. 5 is a view showing an approximate B-H curve of the flyback transfonner of FIG. 4;
  • FIG. 6 is a view showing the 8-H curves of the flyback transfonner in terms of the thickness and characteristics of the temperature-sensitive ferrite;
  • FIG. 7 is a view showing curves representing the effect of the temperature-sensitive ferrite in terms of temperature variations.
  • FIGS. 8 and 9 are views showing how to mount the temperature-sensitive ferrite in the flyback transformer embodying the present invention by way of example.
  • numerals l to 4 represent a core, gap, primary coil and high voltage coil respectively, which are similar to those of the conventional flyback transformers.
  • a temperature-sensitive ferrite member 5 utilizing the Curie point is inserted in the gap 2 instead of making the latter great as in the prior art.
  • This temperature-sensitive ferrite member 5 is made of a ferrite which is ferromagnetic in an ambient temperature range but loses its magnetic property, so as to become paramagnetic when a predetermined temperature is reached.
  • This material is provided in the portion of the gap 2, and the transformer is normally operated in the vicinity of the saturation point as shown in FIG. 5, thereby improving the high voltage stability.
  • FIG. 6 shows B-I-I curves in terms of an air gap and temperature-sensitive magnetic material.
  • the curve for the case where the gap is zero rapidly becomes saturated, so that p. is remarkably decreased when the operating point is varied, so that L is decreased, resulting in abnormal operation of the flyback transformer.
  • the permeability p. remains substantially unchanged even if the operation point is changed, which makes no contribution to the high voltage stability, and that when the temperature sensitive ferrite is inserted, there is a point where p. is suitably varied.
  • B-H curves for the cases where a temperature-sensitive ferrite is inserted and those for the cases where no such ferrite is inserted, taking ambient temperature as a parameter.
  • the saturation of the B-H curve becomes remarkably so that u is markedly decreased with a result that L is changed. Consequently, the high voltage generating circuit is brought into an anomalous operating state.
  • a temperaturesensitive ferrite 6 may be inserted in a recess 7 formed in a core 8.
  • a temperature-sensitive ferrite 9 may be fitted in a groove 11 formed in a core 10.
  • a flyback transformer having a ferrite core formed with an air gap and primary and secondary coils wound on said ferrite core for producing a high voltage in a television receiver, wherein the improvement comprises a temperature-sensitive ferrite inserted in said air gap which becomes rapidly paramagnetic when the temperature of said ferrite is increased beyond a predetermined value, said flyback transformer having a relatively low magnetic reluctance at temperatures below said predetermined value and remaining unsaturated at temperatures above said value thereby preventing excessive temperature rise.
  • a flyback transformer having a ferrite core formed with an air gap and primary and secondary coils wound on said ferrite core for producing a high voltage in a television receiver, wherein the improvement comprises a temperature-sensitive ferrite disposed in engagement with a recess formed in said air gap with a configuration similar to said temperature-sensitive ferrite, said ferrite becoming rapidly paramagnetic when the temperature of said ferrite is increased beyond a predetermined value, said flyback transformer having a relatively low magnetic reluctance at temperatures below said predetermined value and remaining unsaturated at temperatures above said value thereby preventing excessive temperature rise.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Automation & Control Theory (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Details Of Television Scanning (AREA)
US883806A 1968-12-12 1969-12-10 Flyback transformer Expired - Lifetime US3662307A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP9146168 1968-12-12
JP5900869U JPS4837774Y1 (enrdf_load_stackoverflow) 1969-06-18 1969-06-18

Publications (1)

Publication Number Publication Date
US3662307A true US3662307A (en) 1972-05-09

Family

ID=26400029

Family Applications (1)

Application Number Title Priority Date Filing Date
US883806A Expired - Lifetime US3662307A (en) 1968-12-12 1969-12-10 Flyback transformer

Country Status (5)

Country Link
US (1) US3662307A (enrdf_load_stackoverflow)
DE (1) DE1961951B1 (enrdf_load_stackoverflow)
FR (1) FR2025984B1 (enrdf_load_stackoverflow)
GB (1) GB1257537A (enrdf_load_stackoverflow)
NL (1) NL157474B (enrdf_load_stackoverflow)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4390819A (en) * 1981-04-02 1983-06-28 Rca Corporation Television receiver ferroresonant power supply using a two-material magnetizable core arrangement
US4415841A (en) * 1981-05-29 1983-11-15 Rca Corporation Television receiver ferroresonant power supply with permanent magnet biasing
US4704578A (en) * 1984-04-20 1987-11-03 Jeumont-Schneider Corporation Thermal compensation method for a magnetic circuit having an oscillating circuit with an inductance coil
GB2232537A (en) * 1989-05-11 1990-12-12 Victor Company Of Japan Flyback transformer for use in television receiver
GB2250139A (en) * 1990-11-20 1992-05-27 Mitsubishi Electric Corp Flyback transformer
US20110043314A1 (en) * 2007-08-10 2011-02-24 James Joseph Hogan Creative transformer
CN111243835A (zh) * 2018-11-29 2020-06-05 施耐德电器工业公司 电流互感器，及包括这种互感器的保护装置和电气断路器

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1005293A (fr) * 1947-06-28 1952-04-08 Cie Ind Des Telephones Perfectionnements aux noyaux magnétiques
US2699532A (en) * 1949-12-21 1955-01-11 Hartford Nat Bank & Trust Co Transformer or choke coil of the core type having an air-gap
US2730681A (en) * 1950-04-20 1956-01-10 Hartford Nat Bank & Trust Co Inductance
US3239783A (en) * 1962-12-14 1966-03-08 Du Pont Temperature-responsive current controlling inductor device

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB390178A (en) * 1931-09-30 1933-03-30 Cyril Henry Page Wheatley A method and apparatus for the purpose of controlling electrical energy

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1005293A (fr) * 1947-06-28 1952-04-08 Cie Ind Des Telephones Perfectionnements aux noyaux magnétiques
US2699532A (en) * 1949-12-21 1955-01-11 Hartford Nat Bank & Trust Co Transformer or choke coil of the core type having an air-gap
US2730681A (en) * 1950-04-20 1956-01-10 Hartford Nat Bank & Trust Co Inductance
US3239783A (en) * 1962-12-14 1966-03-08 Du Pont Temperature-responsive current controlling inductor device

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4390819A (en) * 1981-04-02 1983-06-28 Rca Corporation Television receiver ferroresonant power supply using a two-material magnetizable core arrangement
US4415841A (en) * 1981-05-29 1983-11-15 Rca Corporation Television receiver ferroresonant power supply with permanent magnet biasing
US4704578A (en) * 1984-04-20 1987-11-03 Jeumont-Schneider Corporation Thermal compensation method for a magnetic circuit having an oscillating circuit with an inductance coil
GB2232537A (en) * 1989-05-11 1990-12-12 Victor Company Of Japan Flyback transformer for use in television receiver
GB2250139A (en) * 1990-11-20 1992-05-27 Mitsubishi Electric Corp Flyback transformer
US20110043314A1 (en) * 2007-08-10 2011-02-24 James Joseph Hogan Creative transformer
CN111243835A (zh) * 2018-11-29 2020-06-05 施耐德电器工业公司 电流互感器，及包括这种互感器的保护装置和电气断路器
CN111243835B (zh) * 2018-11-29 2024-12-13 施耐德电器工业公司 电流互感器，及包括这种互感器的保护装置和电气断路器

Also Published As

Publication number Publication date
GB1257537A (enrdf_load_stackoverflow) 1971-12-22
NL6918635A (enrdf_load_stackoverflow) 1970-06-16
DE1961951B1 (de) 1970-10-22
FR2025984A1 (enrdf_load_stackoverflow) 1970-09-11
FR2025984B1 (enrdf_load_stackoverflow) 1974-05-03
NL157474B (nl) 1978-07-17

Similar Documents

Publication Publication Date Title
US2786983A (en) High-voltage transformer
US4009460A (en) Inductor
US3662307A (en) Flyback transformer
US4308495A (en) Transformer for voltage regulators
GB747736A (en) Improvements in or relating to devices comprising a circuit of highly-permeable material and a permanent magnet for producing a pre-magnetizing field in said circuit
JPH0593025U (ja) 電力変換器
US4390819A (en) Television receiver ferroresonant power supply using a two-material magnetizable core arrangement
GB1118243A (en) Raster distortion correction
US5289149A (en) Electron beam adjusting device with magnet rings of differing alnico powdered metal content
EP0013598B1 (en) Combined linearity and side pincushion correction arrangement
US4234824A (en) Combined linearity and side pincushion correction arrangement
US3390364A (en) Variable reactor having coil and signal coils on toroidal core
US3803447A (en) Circuit arrangement for generating a sawtooth current for the horizontal deflection in television display apparatus
US3571606A (en) Saturable reactor type compensating circuit apparatus
US6201360B1 (en) Deflection yoke and cathode-ray tube device
JPH0311800Y2 (enrdf_load_stackoverflow)
US4415841A (en) Television receiver ferroresonant power supply with permanent magnet biasing
US3230414A (en) Deflection amplitude control using auxiliary transformer winding
FI63845B (fi) Saett att bilda en av horisontal- och vertikalavlaenkningen ho ett bildroer beroende varierande fokuseringsspaenning sa mtoppling foer genomfoerande av saettet
US3657729A (en) Degaussing circuit with bucking current source for reducing current in degaussing coil to zero
GB2250139A (en) Flyback transformer
GB1513360A (en) Deflection yoke for colour picture tube
GB939451A (en) Improvements in or relating to a deflection transformer in, or for, a television receiver
US5173644A (en) Convergence correction apparatus
KR960005329Y1 (ko) 편향요크의 미스콘버젼스 보정장치