US3516131A

US3516131A - Apparatus for assembling a multielement electron gun member

Info

Publication number: US3516131A
Application number: US713782A
Authority: US
Inventors: Hidehiko Yoshida; Shinichi Sawagata
Original assignee: Tokyo Shibaura Electric Co Ltd
Current assignee: Toshiba Corp
Priority date: 1967-03-23
Filing date: 1968-03-18
Publication date: 1970-06-23
Anticipated expiration: 1987-06-23
Also published as: FR1588195A; NL6803989A; GB1189613A

Description

June 1970 HlDEHlKO YOSHlDA ETA!- 3,515,131

APPARATUS FOR ASSEMBLING A MULTIELEMENT ELECTRON GUN MEMBER Filed March 18. 1968 2 Sheets-Sheet 1 FIG. 1B

June 23, 1970 HlDEHlKO-YOSHIDA ETAL APPARATUS FOR ASSEMBLING A MULTIELEMENT ELECTRON GUN MEMBER Filed March 18. 1968 2 Sheets-Sheet 2 United States Patent US. Cl. 29-25.19 1 Claim ABSTRACT OF THE DISCLOSURE An apparatus for assembling a multielement electron gun member wherein a gauge provided with a plurality of grooves is fixed to a jig body, each central rod is fitted into each groove in such a manner that the extensions of said rods intersect each other at a point, a support member is slidably engaged with the free end of each rod, the circumferential surface of the support member being so constructed as to secure the parts of each electron gun unit with spacers, and support devices are fitted to the jig body for locating said parts in the prescribed position.

The present invention relates to improvement in an apparatus for assembling a multielement electron gun member used in colour television picture tubes and the like.

A triple electron gun member used in a colour television picture tube, for example, a shadow mask type picture tube is so constructed as to cause electron beams to be focussed at one point on the shadow mask. In such triple electron gun member, the direction of electron beams is directly determined by the electron gun member itself. However, to construct this member, it is required that the parts of each electron gun unit, namely, the cathode electrode and various grids thereof be spatially disposed along the central axis and also that these parts be located exactly in the prescribed position to cause the central axes of these electron gun units to intersect each other at one point on the shadow mask.

Such type of electron gun member is generally prepared using an assembling means. However, the drawbacks associated with the prior art assembling means were, for example, that the direction of electron beams was very likely to be off the mask due to the cause origimating with the structure of said assembling means itself. Consequently it has been desired to improve the structure of such means in order to eliminate such shortcomings.

The present invention is intended to eliminate the aforementioned drawbacks incurred with the prior art assembling means.

The invention can be more fully understood from the following detailed description when taking into consideration the accompanying drawings, in which:

FIGS. 1A and 1B are profiles of an embodiment of the present invention with parts thereof broken away;

FIG. 2 is a section on line IIII of the embodiment shown in FIG. 1A; and

FIG. 3 is a perspective of the main part of the above embodiment.

On the base of a jig body 1 there are provided at equal intervals three support

arms

2, 2, 2 extending upwardly from the periphery thereof. To the upper inner side of the

support arms

2, 2, 2 is fitted a gauge 3 having an inverted truncated conical shape. On the outer circumferential surface of the gauge 3 are perforated at equal intervals in a concentric line three V-shaped grooves 3,516,131 Patented June 23, 1970 a a and a extending in the direction of a bus. These V-shaped grooves a a and a are respectively disposed between the

support arms

2, 2, 2. Into these grooves are fitted the bottom ends of central rods b b and b;,. The central axes of these rods respectively define an angle 0 with the central axis A-A of the jig body 1, namely, these rods are arranged in such a manner that the central axes of three electron gun units intersect each other at one point in their extension. To one side of the

support arms

2, 2, 2 are pivoted keep plates c c and 0;, in a manner to cause one end thereof respectively to be rotated in a horizontal plane around

axles

4, 4, 4, and to the other side of the

support arms

2, 2, 2 are similarly pivoted levers d d and d;, at one end so as to be rotated in a vertical plane. At the upper ends of the levers d d and d are provided

knobs

5, 5, 5. Below the

support arms

2, 2, 2 are pivoted support devices e e and 6 so as to be rotated around horizontal axles 6, 6, 6 in a vertical plane radially in relation to the central axis of the gauge 3. At the upper end of the support devices e e and e are positioned cylindrical members 7. Into the hole of each cylindrical member 7 is slidably fitted a sliding rod 8. This sliding rod 8 is provided with a guide pin 10 to be fitted into an L-shaped slot 9 perforated in the cylindrical member 7. At the upper end of the sliding rod 8 is located a handle (grip) 11. Also to the lower end of the sliding rod 8 is fitted a receiving means 13 shaped to fit a support plate 12 for a cathode tube. Between the receiving means 13 and the cylindrical member 7 is inserted a compression spring 14. The upper ends of the central rods b b and 12 are closely fitted into the hollow areas provided at the bottom ends of the locating support members f f and f The upper outer circumferential surfaces of these support members are gently tapered (see FIG. 3), and into each of the circumferential surfaces are tightly fitted the parts of each electron gun unit such as four

grid electrodes

15, 16, 17 and 18 by the aid of, for example, four

spacers

19, 20, 21 and 22. The axial centre of these parts of the electron gun is aligned with that of the locating support members, and the spacers keep the parts at the prescribed intervals in relation to the direction of the axial centre. The bottom ends of the locating support members are securely held on the bottom plane of the truncated conical gauge 3. This gauge is supported by the

support arms

2, 2, 2 in such a manner that downward from the bottom end of each central rod in the direction of the central axis there is allowed as long a free space as above the central rod. On the lower outer circumferential surfaces of each locating support member is provided a magnet 23 to attract the inside of the respective support devices e e and e;,.

There will now be described the method of employing the apparatus of the present invention. First, the support devices e e and e are opened by causing them to rotate outwardly as indicated by a dotted line in FIG. 1A. Raise the sliding rod 8 using the handle 11 up to the position denoted by a dotted line in FIG. 1A against the elastic force of the spring 14. Rotate the sliding rod 8 to cause the guide pin 10 to engage with the upper bend of the slot 9. Fit a support plate 12 for the cathode tube into a means 13 for receiving the bottom end of the sliding rod 8. Insert the central rods b b and b into the grooves a a and a perforated in the circumferential surface of the gauge 3. Rotate the keep plates c c and c to the position shown in FIG. 2, to the position shown by the dotted line of FIG. 3 so as to hold the central rods b b and h in the grooves. Rotate the levers d d and d upward using the

knobs

5, 5, 5 so as to cause the keep plates c c and 0 to stand at rest by engagement with the levers as shown by the solid line of FIG. 3. Slidably engage the hollow locating support members f f and 3 f with the upper parts of the central rods [1 b and b On each outer circumferential surface of the locating support members f f and f;, are arranged a grid elec trode 18, a spacer 22, a grid electrode 18, a spacer 21, a grid electrode 16, a spacer 20, a grid electrode 15 and a spacer 19 in the order mentioned in such a manner that these electron gun parts are secured in place as if clamped by the spacers. Rotate the support devices e e and e3 to the position shown by the solid line of FIG. 1A so as to align the central axes of the sliding rods 8 with those of the central rods b b and b At this time the magnets 23 attract the insides of the support devices e e and 2 so that these devices are kept in such a position as shown in FIG. 1B. Rotate the sliding rod 8 by the knob 11 to remove the guide pin 10 from the L-shaped slot 9. Then the elastic force of the spring 14 causes the receiving means 13 and the cathode tube support plate 12 to press the spacer 19 so as to ensure that the grid electrodes and spacers are all pressed to the prescribed position. The outermost surface of the gauge 3, namely, the bottom plane of the truncated cone is flat and controls the positioning of the bottoms of the locating support members f f and f and consequently the positioning of the electron gun parts in the X-Y plane. Using an insulating glass depositing means (not shown), three electron gun units are fixed in place by fusing to each of three support rods consisting of slender glass rods or the like the adjacent ends of

foot plates

31, 32, 33, 34 and 35 previously fitted to the cathode tube support plate 12 and four grid electrodes 15, 1 6, 17 and 18 respectively.

The removal from the jig body 1 of a triple electron gun member thus assembled is carried out as follows. First, raise the sliding rod 8 against the elastic force of the spring 14 using the knob 11, androtate the rod to engage the guide pin 10 with the upper bend of the slot 9, thereby to remove the receiving means 13 from the cathode tube support plate 12. Rotate the support devices e e and e to the position shown by the dotted line of FIG. 1B. Rotate the levers d d and d downward using the

knobs

5, 5, to release the keep plates c c and c Since the keep plates are rotated outwardly, namely, to the position indicated by the dotted line of FIG. 3, the central rods b b and b are also disengaged. Press downward a protrusion 30 at the bottom ends of the central rods b b and b using a tool (not shown) to let fall the rods to the position shown by the dotted line of FIG. 1B. Then the upper parts of the rods are separated from the locating support members f f and f so that the triple electron gun member can be drawn out sidewise along with the support members. Pull the support members downward from the triple electron member, and the

spacers

19, 20, 21 and 22 sidewise therefrom. Then there will be obtained a free triple electron gun member.

As mentioned above, the present invention enables the triple electron gun member to be easily taken out of an assembling means, without displacing the direction of each electron gun unit, but with the prescribed arrangement thereof accurately maintained.

While the invention has been described in connection with, some preferred embodiments thereof, the invention is not limited thereto and includes any modifications and alterations which fall within the true spirit and scope of the invention as defined in the appended claim.

What is claimed is:

'1. An apparatus for assembling a multielement electron gun member comprising a jig body; a plurality of locating support members each consisting of a hollow rod having a tapered upper end portion fitted into the inner diameters of the parts of each electron gun unit and a hollow lower end portion and intended to arrange the parts of each electron gun unit so as to cause the central axes thereof to be aligned together; a plurality of spacers for securing the parts of each electron gun unit at the prescribed intervals in relation to the central axis; a plurality of central rods each having the upper end removably fitted into the lower end of the locating support member and the central axis aligned with those of the electron gun parts; a gauge of an inverted truncated conical shape having a plurality of grooves provided parallel with the truncated conical bus and at equal intervals in a concentric line and mounted on the jig body in such a manner that downward from the lower end of each central rod along the central axis thereof there is allowed as long a free space as above the upper end thereof, said lower end of each central rod being fitted into each groove and said lower end of each locating support member being disposed in close contact with the bottom plane of the truncated conical gauge; a means for fixing the central rod to the prescribed positions in the groove; and a plurality of support devices for locating the parts of ,each electron gun unit by removably pressing the upper ends of said electron gun parts downward along the central axis thereof, said support device having the lower end pivoted to the jig body and being arranged to rotate in a vertical plane including the groove rod radially in relation to the central axis of the gauge.

References Cited UNITED STATES PATENTS 2,914,317 11/1959 Miller et al 29-2519 XR 2,985,947 5/1961 Curd et al. 29-25.19 3,434,819 3/1969 Merchant et al 2925.19 XR JOHN F. CAMPBELL, Primary Examiner R. B. LAZARUS, Assistant Examiner US. Cl. X.R. 269254, 126