US3783424A

US3783424A - Toroidal yoke for television cathode ray tube

Info

Publication number: US3783424A
Application number: US00307027A
Authority: US
Inventors: C Torsch
Original assignee: GTE Sylvania Inc
Current assignee: GTE Sylvania Inc
Priority date: 1972-11-16
Filing date: 1972-11-16
Publication date: 1974-01-01
Anticipated expiration: 1991-01-01

Abstract

A deflection yoke for a cathode ray tube comprises a hollow, substantially frusto-conical core having a plurality of coils toroidally wound thereabout. The coils have terminations to which connections will be made. A plurality of first projections are formed on the core and are circumferentially distributed thereabout between the ends of the core. A plurality of second projections are formed on the wide end of the core and are also circumferentially spaced thereabout. An annular terminal board for receiving the coil terminations is fitted over the narrow end of the core and is provided with slots for engaging the first projections. A protective housing having a shape roughly corresponding to the core is fitted over the terminal board and at its forward end is provided with slots which engage the second projections.

Description

United States Patent [191 [111 3,783,424 Torsch Jan. 1, 1974 TOROIDAL YOKE FOR TELEVISION CATHODE RAY TUBE [75] Inventor: Charles Edward Torsch, Geneva,

[73] Assignee: GTE Sylvania Incorporated, Seneca Falls, NY.

[22] Filed: Nov. 16, 1972 121 1 Appl. No 307,027

[52] [1.8. CI. 335/210, 317/101 [51] Int. Cl H01! [58] Field of Search 335/210; 313/75, 3l3/76;317/101 [56] References Cited UNITED STATES PATENTS 3,569,881 3/1971 Torsch 335/210 2,980,815 4/1961 Ecker 335/210 X 3,390,363 6/1968 Weyrich et al. 335/210 3,629,750 12/1971 Nienaber 335/210 3,307,128 2/1967 Kriadis 335/212 Primary Examiner-George Harris Att0rneyNorman J. OMalley et al.

[ 5 7 ABSTRACT A deflection yoke for a cathode ray tube comprises a hollow, substantially frusto-conical core having a plurality of coils toroidally wound thereabout. The coils have terminations to which connections will be made. A plurality of first projections are formed on tho core and are circumferentially distributed thereabout between the ends of the core. A plurality of second pro jections are formed on the wide end of the core and are also circumferentially spaced thereabout. An annular terminal board for receiving the coil terminations is fitted over the narrow end of the core and is provided with slots for engaging the first projections. A protective housing having a shape roughly corresponding to the core is fitted over the terminal board and at its forward end is provided with slots which engage the second projections.

5 Claims, 3 Drawing Figures TOROIDAL YOKE FDR TELEVISION CATHODE RAY TUBE BACKGROUND OF THE INVENTION This invention relates to yokes for cathode ray tubes and more particularly to a toroidally wound yoke assembly for use on a cathode ray tube.

Toroidally wound deflection yokes for cathode ray tubes are known in the art. Such yokes comprise a frusto-conical core having a plurality of toroidally wound coils thereabout. The terminations of the coils end in a terminal board which is affixed to the outside base of the yoke at the narrow end thereof. Connecting wires leading to a plug are also connected to the terminal board.

This arrangement of .the terminal board at the outside base of the core reducesthe amount of axial movement of the yoke along the neck of the tube and increases the difficulty of determining proper yoke position. This is particularly true since other components such as the convergence assembly are also positioned on the neck of the tube.

OBJECTS AND SUMMARY OF THE INVENTION It is, therefore, an object of this invention to obviate the disadvantages of theprior art.

It is another object of the invention to reduce the overall length of a toroidally wound yoke without affecting its performance.

These objects are accomplished in one aspect of the invention by the provision of a yoke having terminal board mounting means formed intermediate the ends of the yoke. An annular terminal board is affixed to the mounting means and does not extend beyond the base and thus does not add to the axial length of the yoke, Such a design allows much greater felxibility of yoke positioning than was possible heretofore.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explodedperspective view of a yoke embodying the invention;

FIG. 2 is an elevational view of an assembled yoke minus the housing; and

FIG. 3 is an elevational view of the yoke with the housing in place.

DESCRIPTION OF THE PREFERRED EMBODIMENTS For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in conjunction with the above-described drawings.

Referring now to thedrawings with greater particularity, there is shown in FIG. 1 a disassembled yoke having a hollow, substantially frusto-conica] core 12 of a magnetizable material. Core 12 has a wide forward portion or end 14 and a narrow base portion or end 16. The core 12 is toroidally wound with a plurality of coils 18 (see FIGS. 2 and 3)and is further provided with a plurality of first projections 20 intermediate the

ends

14 and 16. The projections 20 can be substantially equally circumferentially spaced thereabout or the spacing can be unequal in order to provide a keying arrangement. Additionally, the projections 20 can be formed as part of a rear crown 22 of a suitable electrically insulating material, as is shown in FIG. 1, or they can be bonded directly to core 12 ;by means of a suit- V able adhesive agent.

A plurality of second projections 24 are provided at the wide end 14 of core 12. These projections 24 likewise can be bonded directly to the core 12 or can be formed as part of a forward crown 26. Second projections 24 are substantially equally circumferentially spaced thereabout.

An annular terminal board 28 is provided with a central aperture 30 large enough to fit over the narrow end 16 of core 12 or rear crown 22. The inner wall 32 of aperture 30 is provided with a plurality of slots 34, equal in number and spacing to first projections 20 and formed to mate therewith. The board 28 can be held in position on projections 20 by cementing with a suitable agent or by melting the ends of first projections 20 and forming them over the board.

The terminations of coils 18 are affixed to terminal posts 36 on board 28 .whereat other connections are made to provide leads 38 to a suitable plug 40 for connection to anappropriate source of power (see FIG. 2).

A protective housing 42 is also'provided, of substantially frusto-conical configuration and of a size to completely encompass yoke 10. The housing 42 comprises an annular forward section 44 and a cup-like base section 46 the bottom 48 of which is provided with a centrally located aperture 50 at least large enough to pass over the neck 51 of a cathode ray tube52, shown in phantom in FIG. 3. The walls 54 of base section 46 extend axially along core 12 at a distance sufficient to provide protection for terminal board 28. The forward section 44 and base section 46'are connected together by a plurality of spaced ribs 56 whereby a series of windows is provided in housing 42.

Further, the forward section 44 is provided with mating means 58, in this case a plurality of slots 60 for engagement with second projections 24. Engagement in this instance is by a force fit which utilizes the natural springiness of the housing material, which is preferably a suitable electrically insulating plastic. The plug 40 is passed through one of the windows in the housing 42.

It will be seen that the novel yoke construction described above adds greatly to the amount of adjusting movement of the yoke and provides an advance in the art.

While there have been shown and described what are at present considered to be the preferred embodiments of the invention, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined by the appended claims.

What is claimed is:

1. A deflection yoke for a cathode ray tube comprising: a hollow, substantially frusto-conical core; a plurality of coils toroidally wound above said core having terminations; a plurality of first projections formed on said core intermediate the ends thereof; a plurality of second projections formed on the wide end of said core and substantially circumferentially spaced thereabout; a rigid, planar annular terminal board for receiving said terminations fitted over said narrow end of said core having slots therein engaging said first projections; and

a protective housing having a shape ro'ughly corresponding to said core fitting over said terminal board and having slots which engage said second projections.

2. The yoke of claim 1 wherein said first and second projections are formed respectively on a rear crown said terminal board; said forward section and said base section being connected together by a plurality of spaced ribs whereby a series of windows is provided in said housing.

4. The invention of claim 2 wherein said crowns are formed of a non-magnetic material.

5. The invention of claim 3 wherein said housing is formed of a non-magnetic material.

Claims

1. A deflection yoke for a cathode ray tube comprising: a hollow, substantially frusto-conical core; a plurality of coils toroidally wound above said core having terminations; a plurality of first projections formed on said core intermediate the ends thereof; a plurality of second projections formed on the wide end of said core and substantially circumferentially spaced thereabout; a rigid, planar annular terminal board for receiving said terminations fitted over said narrow end of said core having slots therein engaging said first projections; and a protective housing having a shape roughly corresponding to said core fitting over said terminal board and having slots which engage said second projections.

2. The yoke of claim 1 wherein said first and second projections are formed respectively on a rear crown and a forward crown, said crowns being respectively fixed to said narrow end of said core and said wide end of said core.

3. The yoke of claim 1 wherein said protective housing comprises an annular forward section and a cup-like base Section, the bottom of said base section being provided with a centrally located aperture at least large enough to pas over the neck of said cathode ray tube, the walls of said base section extending axially along said core a distance sufficient to provide protection for said terminal board; said forward section and said base section being connected together by a plurality of spaced ribs whereby a series of windows is provided in said housing.