US3806108A

US3806108A - Work holder for assembling a cathode ray tube envelope

Info

Publication number: US3806108A
Application number: US00192816A
Authority: US
Inventors: H Adachi; Y Tsukamura
Original assignee: Sony Corp
Current assignee: Sony Corp
Priority date: 1970-10-30
Filing date: 1971-10-27
Publication date: 1974-04-23
Anticipated expiration: 1991-04-23
Also published as: FR2110142A5; JPS523551B1; NL7114977A; GB1371520A; DE2154083A1; CA960284A

Abstract

A cathode ray tube envelope consisting of a neck portion, a funnel portion and a panel portion having a rectangular screen is assembled with reference to the round portion of the funnel portion. The cross section of the round portion is circular and accordingly the geometric center of the funnel portion can be detected easily.

Description

United States Patent [19'] Adachi et a1.

[451 Apr. 23, 1974 1 WORK HOLDER FOR ASSEMBLING A CATHODE RAY TUBE ENVELOPE [75] Inventors: Hiroshi Adachi, Yokohama;

Yoshihiro Tsukamura, Kawasaki, both of Japan [73] Assignee: Sony Corporation, Tokyo, Japan [22] Filed: Oct. 27, 1971 [21] App]. No.: 192,816

[30] Foreign Application Priority Data Oct. 30, 1970 Japan 45-96239 [52] U.S. Cl 269/287, 29/25.l9, 269/321 T [51] Int. Cl B23q 3/00 [58] Field of Search 29/25.l3, 25.19, 25.2,

29/203 J, 203 P; 220/21 A; 316/], 27, 31; 65/58; 269/287, 305, 321 T [56] References Cited UNITED STATES PATENTS 3,329,422 7/1967 Hajduk 269/287 3,369,881 2/1968 Bennett et al. 65/58 2,889,952 6/1959 Claypoole 65/58 X 3,118,662 l/l964 Fassett et al.. 269/305 X 3,305,123 2/1967 Nordby 220/21 A 5/l968- Reinwall, Jr. 220/21 A X Primary ExaminerRoy Lake ssistq t ExaminerJ. W. Davie Attorney, Agent, or F irm-Hill, Sherman, Meroni, Gross and Simpson [5 7] ABSTRACT A cathode ray tube envelope consisting of a neck portion, a funnel portion and a panel portion having a rectangular screen is assembled with reference to the round portion of the funnel portion. The cross section of the round portion is circular and accordingly the geometric'center of the funnel portion can be detected easily.

3 Claims, 3 Drawing Figures P/ m 7A A L Y MOUNTED PATENTED APR 2 3 I914 SHEET 2 OF 2 INVENTORS YwHIHI/W HUM/4W1 M t JWATTORNEY WORK HOLDER FOR ASSEMBLING A CATI-IODE RAY TUBE ENVELOPE BACKGROUND OF THE INVENTION 1. Field of the Invention v a This invention relates to cathoderay tube envelopes, and more particularly to a method of the fabrication of color television picture tube envelopes having a rectangular panel screen.

2. Description of the Prior Art Generally, glass cathode ray or color television picture tube envelopes consist of a neck portion having enclosed therein an electron gun, a funnel portion having wide and narrow openings at opposite ends thereof and a viewing panel portion having formed thereon a phosphor screen and, if necessary, having attached thereto a shadow mask, these portions being sealed together as by frit glass to form a completed tube envelope. In this case, the three portions must be assembled together precisely in predetermined relationships to one another.

Namely, inaccurate assembling of the three portionscauses low purity, mislanding, misconvergence and so on, and hence is undesirable for the fabrication of color television receiving sets.

To avoid such a defect, various methods and apparatus for assembling cathode ray or color television picture tube envelopes have heretofore been proposed but no satisfactory ones have been realized.

SUMMARY OF THE INVENTION Accordingly, one object of this invention is to provide an apparatus for assembling cathode ray tube envelopes with which it is possible to seal the neck, funnel and panel screen portions together as a unitary structure with these portions being precisely aligned with one another.

Another object of this invention is to provide a .method for assembling the neck portion and/or panel screen portion with a funnel portion with reference to the round portion (defined later on) of the funnel portion of a tube envelope.

Another object of this invention is to provide a method for assembling the neck portion with the funnel portion of a tube envelope with reference to the round portion of the latter.

Another object of this invention is to provide a method for assembling the panel screen portion with the funnel portion of a tube envelope with reference to the round portion of the latter.

Another object of this invention is to provide a jig for inspection of a composite funnel-neck article with reference to the round portion of the funnel portion.

Still another object of this invention is to provide a novel method for assembling a cathode ray tube having a rectangular panel screen.

Other objects, features and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic diagram, for explaining this invention;

DESCRIPTION OF THE PREFERRED EMBODIMENTS For a better understanding of this invention, a brief description will be given first of a conventional cathode ray tube envelope and a method of assembling it in connection with FIG. 1. A neck portion 1 is sealed to a sealing end 2b of a funnel portion 2 with the geometric center axis X--X of the former being aligned with that O of a sealing end 2a of the latter and a panel screen portion 3 is sealed to the sealing end 2a of the funnel portion 2 with the geometric center P being aligned with that O of the former, thus providing a composite article 4. Of course, the geometric center axis X--X of the neck portion 1 is selected perpendicu lar to the sealing end 2a of the funnel portion 2 and/or the viewing screen of the panel screen portion 3. With such a conventional method, however, it is very different precisely to find out the geometric center 0 of the sealing end 2a of the funnel portion 2. The present invention does not involve such detection of the geometric center of the sealing end 2a, and hence allows much ease in the fabrication of cathode ray tube envelopes.

In FIG. 2, reference numeral 5 indicates generally an apparatus or a jig for assembling a cathode ray tube envelope. The apparatus 5 comprises a first positioning means 8 for aligning the center of a round portion 13 of a funnel portion 2 with the geometric center of a neck portion 1 and, preferably, a second positioning means 10 for aligning the geometric center P of a panel screen portion 3 with the extension YY of a line joining the center of the first positioning means 8, that is, the round portion 13 with the center of the neck portion 1.

The round portion 13 of the funnel portion 2 herein mentioned is one part of the tubular portion of the funnel 2 which may include a small open end 2!) and on which a deflection coil assembly (not shown) is mounted and the round portion 13 substantially corresponds to the center of electron beam deflection. This will be described a little more in detail. In a cathode ray tube having a rectangular panel screen, itssealing end 211 is naturally substantially rectangular but the sealing end 2b is circular, of course. Considering any given cross sections of the funnel 2 between, the two sealing ends thereof, the cross section of the funnel 2 is rectangular at its sealing end 2a but becomes gradually round as the sealing end 2b is approached and truly circular at the sealing end 2b. Here, the portion of the funnel 2 where its crosssection becomes round is defined as a round portion in this specification. This round portion is used as a reference portion of the cathode ray tube according to this invention.

The first positioning means 8 consists of a circular, ring-shaped member 6 for receiving the round portion 13 of the funnel 2 and, for example, a pair of holders 7a and 7b extending downwardly thereof for holding that portion of the neck portion 1 in which an electron gun is disposed. At least one of the holders 7a and 7b is formed integrally with the ring-shaped member 6 and the other is pivotally mounted to the member 6 for pressing the neck portion 1 to the one holder. Further, the first positioning means 8 is designed so that a line joining the center of the ring-shaped member 6 with that of a circular space defined by arc-shaped depressions of the both holders 7a and 7b may be aligned with a vertical line YY. Namely, by setting the neck portion 1 on the positioning means 8, mounting the funnel 2 thereon and sealing them to each other, the center of the round portion 13 automatically coincides with the center of the neck portion 1.

The second positioning means consists of an arm 16 extending upward from the ring-shaped member 6 and an L-shaped limit member 14 extending laterally from the upper end of the arm 16 to conform to two adjacent side walls of the rectangular panel screen portion 3. The L-shaped member 14 carries two position adjusting screws A and 15B in its one side and one position adjusting screw 15C in the other side.

These first and second positioning means 8 and 10 are supported by a base 9 secured to the ring-shaped member 6. The base 9 is made up of three base member 1 1a, 1 1b and 1 10 arranged, for example, in a triangular form and three supports 12a, 12b and 12c formed integrally therewith. The first and second positioning means 8 and 10 and the base 9 are formed of, for example, iron, as a unitary structure with one another as will be seen from the figure. The neck, funnel and

panel screen portions

1, 2 and 3 are placed one on another with the use of the jig 5 and placed, as they are, in a furnace to be sealed together with frit glass to produce a completed cathode ray tube envelope. In this case, the neck, funnel and

panel screen portions

1, 2 and 3 are positioned as predetermined by the holders 7a and 7b, the ring-shaped member 6 and the L-shaped limit member 14.

There are some occasions when the panel screen portion 3 is assembled with a composite funnel-neck article by the use of the jig 5 shown in FIG. 2. In such a case, the composite funnel-neck article is mounted on the jig 5. Since the ring-shaped member 6 and the holders 7a and 7b are constructed as previously described, the extension connecting the center of the neck portion 1 with that ofthe round portion 13 of the funnel 2 coincides with the perpendicular YY which serves as the reference line.

Then, an examination is made as to whether the open end face of the funnel 2 to be sealed to the panel screen portion 3, that is, the so-called sealing end 2a is perpendicular to the reference line YY. This examination is achieved in such a manner as depicted in FIG. 3. Namely, a plurality of measuring points G G and G which abut against the sealing edge with the ringshaped member 6, that is, the round portion sealing 13 being used as the reference, is provided in association with the jig 5 and the gradient of the sealing edge 2a is measured from the amount of displacement (height) of each of the measuring points 0,, G and G When the sealing edge 20 is not perpendicular to the reference line YY, the sealing edge 2a is ground to be perpendicular to the line YY, then, the panel screen portion 3 is placed on the funnel 2. At this time, by the pre-adjusted screws 15A, 15B and 15C of the second positioning means 10, the center P of the panel screen portion 3 is aligned with the reference line YY and then the panel screen portion 3 is fixed to the funnel 2 by means of frit glass.

With the present invention described above, sealing of the funnel 2 to the panel screen portion 3 is achieved using as a reference the line connecting the center axis of the neck portion 1 with the center of the round portion 13 of the funnel 2. This allows ease in aligning the axes of a deflection yoke magnetic field and an electron beam with each other in the subsequent assembling of an electron gun and a deflection coil assembly with the tube envelope, thereby to facilitate assembling of cathode ray tubes. Further, this invention does not necesitate detection of the center of the sealing end 2a, so that assembling of the funnel 2 with the panel screen portion 3 is easy.

As has been described above, the line connecting the axis of the electron gun with the electron beam deflection center is used as the reference line, so that even if the funnel 2 and the neck portion 1 are sealed to each other a little out of position, the composite funnel-neck article can be used, with the result that yield of the cathode ray tube envelopes can be raised.

In the foregoing example the centers 0 and P of the round portion 13 of the funnel 2 and the panel screen portion 3 are aligned with the geometric center axis XX of the neck portion 1 but the neck portion 1 may be a little inclined to the panel screen portion 3 so long as the electron gun and the panel screen portion 3 are. in' predetermined alignment with each other. Namely, it is sufficient only to position the centers 0 and P of the round portion 13 of the funnel 2 and the panel screen portion 3 on the line passing through the center of any cross section of the neck portion 1.

It willbe apparent that many modifications and variations may be effected without departing from the scope of the novel concepts of this invention.

We claim as our invention:

1. A jig for assembling a cathode ray tube envelope formed of two joined component parts which include: a tubular neck part and a funnel part having a small end portion of circular cross section and a large end portion of generally rectangular cross section, said parts joined together forming a portion of a cathode ray tube; said jig comprising a frame which includes at least a portion of an annular seat for receiving and seating said funnel part in. a region where its cross section is circular, at least one arm in fixed relation to said annular seat located below said annular seat, said arm having receiv-, ing means for positioning said neck part, said receiving means determining the location of the geometric center axis of said neck part, and said annular seat determining the location of the geometric center of said funnel part in the plane of said annular seat, said geometric center point of the funnel part intersected by the geometric center axis of the neck part.

2. A jig for assembling a cathode ray tube envelope formed of a plurality of component parts which include: a tubular neck part, a funnel part joined to said tubular neck part and having a small end portion of circular cross section and a large end portion of generally rectangular cross section, and a rectangular panel part to form a cathode ray tube envelope; said jig comprising a frame which includes at least a portion of an annular seat for receiving and seating said funnel part in a region where its cross section is circular, at least one arm in fixed relation to said annular sea't located below said annular seat, said arm having receiving means for holding said neck part, an upstanding arm rigidly secured to said frame and having a fixed relation to said cation of the geometric center of said panel part in a second plane parallel to said first plane, said geometric center axis passing through said geometric centers of said funnel part and said rectangular panel part.

3. Ajig according to claim 1, in which a plurality of contacts are provided to determine the perpendicularity of the edges of the rectangular portion of the funnel part to the geometric center axis of the neck part.

Claims

1. A jig for assembling a cathode ray tube envelope formed of two joined component parts which include: a tubular neck part and a funnel part having a small end portion of circular cross section and a large end portion of generally rectangular cross section, said parts joined together forming a portion of a cathode ray tube; said jig comprising a frame which includes at least a portion of an annular seat for receiving and seating said funnel part in a region where its cross section is circular, at least one arm in fixed relation to said annular seat located below said annular seat, said arm having receiving means for positioning said neck part, said receiving means determining the location of the geometric center axis of said neck part, and said annular seat determining the location of the geometric center of said funnel part in the plane of said annular seat, said geometric center point of the funnel part intersected by the geometric center axis of the neck part.

2. A jig for assembling a cathode ray tube envelope formed of a plurality of component parts which include: a tubular neck part, a funnel part joined to said tubular neck part and having a small end portion of circular cross section and a large end portion of generally rectangular cross section, and a rectangular panel part to form a cathode ray tube envelope; said jig comprising a frame which includes at least a portion of an annular seat for receiving and seating said funnel part in a region where its cross section is circular, at least one arm in fixed relation to said annular seat located below said annular seat, said arm having receiving means for holding said neck part, an upstanding arm rigidly secured to said frame and having a fixed relation to said annular seat, said upstanding arm terminating in an L-shaped horizontally extending flange which engages said panel part of a plurality of points, said receiving means determining the location of the geometric center axis of said neck part, said annular seat determining the location of the geometric center of said funnel part in a first plane determined by the plane of said annular seat perpendicular to the geometric center axis of said neck part, and said upstanding arm determining the location of the geometric center of said panel part in a second plane parallel to said first plane, said geometric center axis passing through said geometric centers of said funnel part and said rectangular panel part.

3. A jig according to claim 1, in which a plurality of contacts are provided to determine the perpendicularity of the edges of the rectangular portion of the funnel part to the geometric center axis of the neck part.