US3898510A

US3898510A - Electrical conductive means for traversing a cathode ray tube envelope to effect multiple connections therein

Info

Publication number: US3898510A
Application number: US483554A
Authority: US
Inventors: Charles A Davis; Donald L Say
Original assignee: GTE Sylvania Inc
Current assignee: GTE Sylvania Inc
Priority date: 1974-06-27
Filing date: 1974-06-27
Publication date: 1975-08-05
Anticipated expiration: 1992-08-05
Also published as: DE2528276A1; DE7520174U

Abstract

Improved through-the-seal electrical conductive means are provided for use in a cathode ray tube to effect multiple connections within the envelope structure. The conductive member being associated with the funnel-panel seal facilitates a bridging internal connection joining a discrete funnel related area with a related area on the panel wall.

Description

United States Patent 1 1 Davis et al.

[451 Aug. 5, 1975 ELECTRICAL CONDUCTIVE MEANS FOR TRAVERSING A CATI'IODE RAY TUBE ENVELOPE TO EFFECT MULTIPLE CONNECTIONS THEREIN [75] Inventors: Charles A. Davis, Auburn; Donald L. Say, Waterloo, both of NY.

[73] Assignee: GTE Sylvania Incorporated,

Stamford, Conn.

22 Filed: June 27, 1974 211 App1.No.:483.554

[52] US. Cl. 313/482; 313/450; 313/479 [51] Int. Cl. ..I-I01 29/02; H011 29/07;

H01J 29/88 [58] Field of Search 313/477, 482, 318, 402.

[56] References Cited UNITED STATES PATENTS Haas 313/318 Schlesinger 313/402 X Engels et al. 313/4142 X Primary E.\'uminerRobert Segal Attorney, Agent, or Firm-Norman J. OMallcy; Frederick H. Rinn; Robert T. Orner 5 7 ABSTRACT Improved through-the-seal electrical conductive means are provided for use in a cathode ray tube to effect multiple connections within the envelope structure. The conductive member being associated with the funnel-panel seal facilitates a bridging internal connection joining a discrete funnel related area with a related area on the panel wall.

6 Claims, 5 Drawing Figures ELECTRICAL CONDUCTIVE MEANS FOR TRAVERSING A CATHODE RAY TUBE ENVELOPE TO EFFECT MULTIPLE CONNECTIONS TI-IEREIN CROSS REFERENCE TO RELATED APPLICATIONS This application contains matter disclosed but not claimed in two related applications filed concurrently herewith and assigned to the assignee of the present invention. These related applications are: Ser. No. 483,555, Cathode Ray Tube Electrical Connective Means, and Ser. No. 483,559, Shielding Means For A Cathode Ray Tube."

BACKGROUND OF THE INVENTION This invention relates to electrical conductive means in a cathode ray tube and more particularly to exteriorinterior electrical conductive means oriented in a manner to traverse the funnel-panel seal region of the envelopic structure of a cathode ray tube.

Certain types of cathode ray tube construction utilize an internal electrical connection between a discrete funnel-related interior area and an associated area disposed on the interior of the adjacent panel portion. For example, in color cathode ray tubes of post-deflection structure, it has been conventional practice to supply the screen potential by utilizing a separate isolated high voltage connection through the tube envelope in conjunction with an associated bridging conductive member to effect a suitable connection with the screen portion of the tube.

Tubes of post-deflection construction commonly employ at least one electrode member oriented between the electron gun assembly and the spatially related patterned display screen. Basically, this type of cathode ray tube is structured to have a color-selection or focusing electrode that is positioned in spaced adjacency with the screen. This color-selection electrode is normally operated at an electrical potential that is of a value lower than that of the screen potential, such difference in related potentials being the primary determining factor as to whether the operation of the tube is post-deflection focusing or post-deflection acceleration.

In post-deflection tubes, the lower potential of the colorselection electrode is usually applied thereto by a resilient connector attached to the electrode in a manner to make contact with the conductive coating interiorly disposed on the inner surface of the funnel portion. This coating conventionally receives its electrical potential from an external source via a metallic conductive button traversing the wall of the funnel portion. Separate electrical conductive means are utilized to supply a higher electrical potential to the screen portion of the tube. A common means for achieving this in the art has been the utilization of an electrical conductor disposed through the region of the panel-funnel seal. A conventional type of connector transversal thus employed has been in the form of a rather light-weight metallic strip embedded in the fritted seal in a manner to traverse therethrough. Usually this has been a fragile type of connective means requiring external application of an insulative potting material thereabout to strengthen and shield the external portion of the connection. The fragility of this sort of light weight connective transversal also presents problems relating to the achievement of the desired internal connections.

Therefore. through-the-seal connections as commonly practiced in the art, have exhibited inherent shortcomings which have been deterrents to their acceptance in commercial usage.

OBJECTS AND SUMMARY OF THE INVENTION It is an object of this invention to reduce and obviate the aforementioned disadvantages that have been evidenced in the prior art. Another object of the invention is to provide a through-the-seal electrical conductive member for utilization in a cathode ray tube that provides improved external and internal electrical connections for the tube. A further object of the invention is to provide an improved through-the-seal electrical conductive means that lends itself to expeditious fabrication and utilization for effecting multiple connections within the tube.

These and other objects and advantages are achieved in one aspect of the invention wherein an improved electrical connective means, for traversing the funnelpanel seal region of the tube envelope, is comprised of a substantially U-shaped metallic transversal element formed from a longitudinal strip of electrical conductive material; such being discretely configurated to have two opposed legs that are oriented in a common direction and joined by a planar bridging portion therebetween. This U-shaped transversal element permits straddle-orientation placement on the sealing edge of the panel portion, or on the sealing edge of the funnel portion, prior to consummation of the frit sealing operation during tube fabrication. A first leg' of the U- shaped configuration is located adjacent to the internal surface of the envelope, with the second leg thereof being positioned adjacent to the external surface of the envelope. Such placement provides holding engagement of the conductive element relative to the sealing edge of the portion of the envelope upon which it is immediately positioned. An associated resilient contacting means is affixed to the first leg of the conductive element in a manner to effect internal pressured electrical connection with at least one conductive area within the envelope. A second leg of the conductive element provides means for effecting an external connection to the transversal conductive element.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a cathode ray tube wherein the invention is utilized;

FIG. 2 is another cross-sectional view taken along the line 22 of FIG. 1;

FIG. 3 is an enlarged perspective showing a portion of the tube incorporating the improved electrical conductivemeans of the invention; and

FIGS. 4 and 5 are partial sectionals further illustrating the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT For a better understanding of the present invention, together with other and further objects, advantages, and capabilities thereof, reference is made to the following specification and appended claims in connection with the aforedescribed drawings.

The improved conductive member of this invention is applicable to cathode ray tube usage wherein it is desired to make electrical connection through the region of the funnel-panel seal to connect separate but related conductive areas disposed on both the panel and funnel portions.

One example of the utilization of the invention is that illustrated in FIGS. 1 and 2 wherein a color cathodev ray tube 11 of post-deflection construction isshown as having a longitudinal axis 13 therethrough and an envelope l comprised of neck 17, funnel l9, and face panel 21 portions, whereof the panel portion is hermetically joined to the funnel portion along the congruent seal 23 effected by a fritting procedure during tube fabrication. The face panel 21 has a viewing area 25 and a substantially perimetrical sidewall portion 27 that is terminated by a sealing seat 29. Formed on the interior surface of the viewing panel is a patterned cathodoluminescent screen 31 disposed in a conventional manner to provide discrete areas of color-emitting phosphor materials definitively patterned as stripes or dots in keeping with the state of the art. A discretely apertured structure 33, in this instance referenced as a color-selection electrode, is spatially related to the patterned screen 31. This screen-related electrode is predeterm inately positioned within the face panel 21 by known means utilized in the art, such as, for example, supporting stud-like members embedded in the sidewall of the panel and projecting therefrom to mate with locators integral with theelectrode member. For purposes of clarity, these conventional stud-like supporting members and mask locators have been eliminated from the drawings.

As shown, the interior of the funnel portion 19 of the cathode ray tube has a skirt-like conductive coating 35 disposed thereon in a manner to extend substantially from the neck portion 17 to the forward region'adjacent the sealing zone 23. This envelopic coating which is usually of the potential of the final electrode of the gun assembly, is formed ofa material such as Aquadag, such being electrically connected to the color-selection electrode 33, by means not shown. The electrical potential for this skirt-like coating is usually supplied thereto by means of a conductive button 37 traversing the wall of the funnel portion 19.

An exemplary embodiment of the invention is illustrated in FIGS. 1, 2, and 3 wherein the improved through-the-seal electrical conductive member 39 is utilized as part of a shielding combination arranged to collect the deleterious secondary low-velocity electrons that are usually present within the tube on the electron gun assembly side of the color-selection electrode member 33. In this embodiment, a desirably defined substantially longitudinal conductive area of screen potential 38 is comprised of the through-theseal electrical conductive member of the invention 39 which is structured to make internal pressured electrical connections with a longitudinal strip of funneldisposed conductive coating 41 and a peripheral tab portion 43 extending from the screen 31. Such pressured internal connections being effected by substantially resilient contacting means 45 which are bonded to the basic U-shapcd metallic transversal element 47 of the conductive member 39. As illustrated, the integrated conductive formation of screen potential 38 is isolated from the skirt-like conductive coating 35 of color-selection electrode potential, covering most of the interior surface of the funnel portion 19, by the interspatial region 49. Immediately in 'front of this discretely formed funnel-related screen potential conductive area 38, and oriented in spatial relationship thereto, is a substantially inverted U-shaped wire shielding formation 51 having the ends thereof positionally affixed to the framing portion of the color selection electrode 33. This U-shaped shield is formed and positioned in a manner to extend a partial distance into the funnel portion 19 of the envelope. The shielding means thus briefly described, of which the conductive means of the invention forms an integral part, effectively removes the secondary electrons from the discrete interior region of the tube. Such shielding means is fully disclosed and described in a related application by Charles A. Davis et al., Ser. No. 483,559, filed concurrently herewith and assigned to the assignee of the present invention.

For greater detail of the through-the-seal electrical conductive member of the invention 39, reference is directed particularly to FIGS. 3, 4, and 5. As portrayed therein, the conductive member includes a substantially U-shaped basic metallic transversal element 47 which is formed from a longitudinal strip of electrical conductive material having a coefficient of thermal expansion substantially matching that of the glass frit material in which it is embedded in the seal structure 23. An exemplary material of this type is a nickel-iron alloy referenced as No. 4' alloy, which is commercially available from GTE Sylvania Incorporated, Warren, Pa. This basic transversal conductive element 47 is configurated to have two opposed legs, 53 and 55 respectively, oriented in a common direction and joined by a planar intermediate bridging portion 57. The terminal ends 54 and 56 of the respective legs are dimensioned apart and flared slightly outward to facilitate positioning of the element. Thus, there is effected a structure that is suitable for sliding placement and straddleorientation on a related and conjunctively shaped terminal wall portion of the envelope structure. This bridging portion is adherently incorporated. in a sandwiched manner, as a conductive transversal through the seal when the funnel and panel portions are subsequently hermetically joined during tube fabrication. As shown in the drawings, this basic U-shaped element 47 is positioned relative to the sealing edge of the panel portion 21 of the tube, but such is not to be considered limiting as placement is also appropriate on the terminal wall of the funnel portion 19, if so desired. Whichever orientation is utilized, the first of the legs 53 is located adjacent to the internal surface of the envelope with the second of the legs 55 being adjacent to the external surface thereof. Such placement positions the intermediate bridging portion 57 of the element 47 relative to one of the sealing seats comprising the related wall structure of the envelope. Each of the respective legs is formed with a slight outward bow to effect a pseudo-horseshoe shaping to the element 47 to accommodate the seal formation, to effect clamping placement, and to facilitate attachment of suitable external connective means.

Interiorly associated with the first leg of the conductive element are resilient contacting means 59 in the form of a longitudinal member having a mid-point 61 from which two opposed resilient tongue-like contacting

members

63 and 65, of a material such as stainless steel, are extended in opposite directions in substantially the plane of the U-shaped basic element 47. These contacting members are oriented in a related axial manner to effect internal pressured contact with two separate areas of the interior surface of the envelope; one being funnel disposed 41 and the other panel disposed 43. This longitudinal contacting member is affixed, such as by welding or brazing, to the first leg 53 at substantially the mid-point related area 61 of the shaped contact member.

A second embodiment of the invention is detailed in FIG. 5 wherein only one resilient contacting tonguelike contacting member 67 is utilized. In this embodiment, the contacting tongue is extended into the funnel portion in an axially related direction to make connection with the defined coating 41 disposed thereon. in the panel portion 21, the conductive coating of the screen 43 is extended to the region of the seal 29, whereat the first leg 53 of the basic conductive element 39 makes contact therewith to consummate the desired bridging connection between the funnel and panel related coatings.

FIGv 5 also illustrates an example of an external connective means 69 associated with the through-the-seal conductive member of the invention. The second leg of the transversal element 55, being slightly outstanding from the external wall of the panel, facilitates the affixation or clamping attachment of an external connector 71 thereto. Surrounding this external connection is an insulative boot or dome-shaped protective means 73 formed of insulative rubber or plastic.

Thus, there is provided an improved through-the-seal electrical conductive member that expeditiously effects external and internal electrical connections for the tube. The improved through-the-seal electrical conductive means of the invention is both expedient and appropriate for providing multiple bridging connections within a cathode ray tube.

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

What is claimed is:

1. Improved electrical conductive means in a cathode ray tube structure whereof the envelope has a longitudinal axis therethrough and includes a face panel having a viewing portion and an encompassing sidewall therearound terminated by a perimetric sealing seat which is bonded by a fritted seal therealong to a compatible sealing seat terminating the wall of a related contiguous funnel portion of the envelopic integration. said electrical conductive means being a through-theseal electrical conductive member comprising:

a substantially U-shaped metallic transversal element formed of a longitudinal strip of electrical conductive material substantially configurated as a pseudo-horseshoe shaping having two opposed legs oriented in a common direction and joined by a planar bridging portion therebetween to effect straddle' orientation and clamping engagement on a terminal wall portion of said envelope, the first of said legs being located adjacent to the internal surface of said envelope with the second of said legs being adjacent to the external surface thereof, the terminal ends of said legs being dimensioned apart and individually flared slightly outward to provide to provide sliding placement of said conductive element relative to one of said sealing seats and the related terminal wall thereof; and

resilient contacting means attached to said first leg in a manner to effect internal pressured electrical connection with at least one conductive area within said envelope.

2. The improved electrical conductive means according to claim 1 wherein the bridging portion of said U shaped conductive element is' bondingly incorporated in a sandwiched manner through said fritted seal.

3. The improved electrical conductive means according to claim 1 wherein said resilient contacting means is in the form of a longitudinal projecting tongue-like contacting member extending substantially in the plane of said U-shaped conductive element in a related axial manner to effect internal pressured contact with the interior surface of said envelope.

4. The improved electrical conductive means according to claim 1 wherein said resilient contacting means is in the form of a longitudinal member having a midpoint from which two opposed resilient tongue-like contacting members are extended in opposite directions in substantially the plane of said U-shapcd conductive element in a related axial manner to effect internal pressured contact with two separate areas of the interior surface of said envelope, said longitudinal member being attached to said first leg of said conductive element at a substantially mid-point related area of said member.

5. The improved electrical conductive means according to claim 1 wherein said U-shaped conductive element is oriented to straddle the panel sidewall with the bridging portion of said element being related to the sealing seat of said panel.

6. The improved electrical conductive means according to claim 1 wherein said U-shaped conductive element is oriented to straddle the funnel sidewall with the bridging portion of said element being related to the sealing seat of said funnel.

Claims

1. Improved electrical conductive means in a cathode ray tube structure whereof the envelope has a longitudinal axis therethrough and includes a face panel having a viewing portion and an encompassing sidewall therearound terminated by a perimetric sealing seat which is bonded by a fritted seal therealong to a compatible sealing seat terminating the wall of a related contiguous funnel portion of the envelopic integration, said electrical conductive means being a through-the-seal electrical conductive member comprising: a substantially U-shaped metallic transversal element formed of a longitudinal strip of electrical conductive material substantially configurated as a pseudo-horseshoe shaping having two opposed legs oriented in a common direction and joined by a planar bridging portion therebetween to effect straddleorientation and clamping engagement on a terminal wall portion of said envelope, the first of said legs being located adjacent to the internal surface of said envelope with the second of said legs being adjacent to the external surface thereof, the terminal ends of said legs being dimensioned apart and individually flared slightly outward to provide to provide sliding placement of said conductive element relative to one of said sealing seats and the related terminal wall thereof; and resilient contacting means attached to said first leg in a manner to effect internal pressured electrical connection with at least one conductive area within said envelope.

2. The improved electrical conductive means according to claim 1 wherein the bridging portion of said U-shaped conductive element is bondingly incorporated in a sandwiched manner through said fritted seal.

4. The improved electrical conductive means according to claim 1 wherein said resilient contacting means is in the form of a longitudinal member having a mid-point from which two opposed resilient tongue-like contacting members are extended in opposite directions in substantially the plane of said U-shaped conductive element in a related axial manner to effect internal pressured contact with two separate areas of the interior surface of said envelope, said longitudinal member being attached to said first leg of said conductive element at a substantially mid-point related area of said member.