JPH0623150U - External terminal of display tube - Google Patents

Abstract

(57) [Summary] [Purpose] To securely connect the extension terminal to the lead-out terminal of the display tube with sufficient strength. [Structure] A through hole 4 is provided in the lead-out terminal portion 2 of the display tube. The extension terminal 3 having a solder layer is overlaid on the through hole 4. Both terminals are sandwiched between the electrodes 5 and 6 and pressed together. The melted solder 7 enters the through hole 4 and hardens, and fixes both terminals by the wedge effect.
Both terminals melt at the edge of the through hole 4 and are firmly fixed at at least two points.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an external terminal of a display tube, and more particularly to an external terminal of an external type display tube in which an extension terminal is joined to a lead-out terminal portion led out of the display tube.

[0002]

[Prior art]

 For example, Japanese Utility Model Publication No. 2-26122 (Japanese Utility Model Application No. 58-83936) discloses a device for an external terminal of a display tube.

This invention is intended to extend the external terminal of the display tube with a separate member to reduce the amount of expensive alloy portion used in the lead-out terminal portion of the display tube. That is, one end of the extension terminal made of a round bar is preliminarily processed into a flat shape, and preliminary solder is provided on the end. Then, the flat portion of the round bar is superposed on the lead-out terminal portion protruding from the display tube, and the two are joined by welding.

[0004]

[Problems to be solved by the device]

 1. The solder of the extension terminal will be melted by welding and will adhere as burrs around the welding point. This burr is easy to peel off, and if other adjacent terminals are short-circuited or the display tube is mounted on a printed circuit board (hereinafter referred to as PCB) and then peeled off and adhered to the circuit, insulation failure will occur. Will end up.

2. Crushing was required to flatten the weld of the extension terminal. For this reason, the manufacturing time was lengthened, and a cleaning process was required to remove oil and other substances that adhered during the crushing process.

3. The extension terminal is a round bar, and the wire diameter varies. The extension terminal with a small diameter had poor conductivity with the welding electrode, and there was a tendency for the welding strength to decrease. For this reason, when connecting extension terminals to a large number of lead-out terminals protruding from the envelope of the display tube in a single process, the joint strength of the extension terminals may vary from terminal to terminal. there were.

An object of the present invention is to make it possible to reliably connect an extension terminal to a lead-out terminal portion of a display tube with sufficient strength.

[0008]

[Means for Solving the Problems]

 The external terminal of the display tube according to the present invention has a lead-out terminal portion led out from the inside of the display tube and having a through hole at one end, and an extension terminal welded at the edge of the through-hole of the lead-out terminal portion. It has a feature.

[0009]

[Action]

 When the extension terminal and the lead-out terminal portion are overlapped and pressed together, the solder plating layer of the extension terminal melts and flows into the through hole of the lead-out terminal portion, fixing them and fixing them by the wedge effect. In addition, heat concentrates on the edge of the through hole that is in contact with the extension terminal, and both are melted along the edge of the through hole. Therefore, it has higher strength than welding at only one point.

[0010]

【Example】

 As shown in FIG. 3, from the sealed portion of the envelope of the display tube 1, a large number of lead-out terminal portions 2 made of 426 alloy are juxtaposed and protrude outward. Although not shown, various electrodes and the like in the envelope are connected to the inner end of each lead-out terminal 2. The extension terminals 3 made of a round bar of Ni—Fe material are connected to the terminals outside the lead-out terminal portion 2.

As shown in FIGS. 1 and 2, a through hole 4 is formed at one outer end of the lead-out terminal portion 2. A solder layer is formed on the surface of the extension terminal 3 in advance. Then, one end of the extension terminal 3 is placed on each of the through holes 4 of each of the lead-out terminal portions 2, and the welding rod 5 for each terminal and the common electrode 6 arranged below sandwich the both electrodes. An electric current is passed between them to perform pressure welding.

Due to the heat generated during welding, the solder layer of the extension terminal 3 melts and flows into the through hole 4 of the lead-out terminal portion 2. Since the lower side of the through hole 4 is blocked by the common electrode 6, the solder 7 will not flow out and be lost. After the welding is completed, the solder 7 is solidified in the through hole 4, whereby the extension terminal 3 and the lead-out terminal portion 2 are firmly joined by the wedge effect. That is, due to the wedge effect of the solder 7, it becomes stronger against the force in the direction indicated by the arrow A in FIG.

The extension terminal 3 whose surface is exposed by melting the solder is in contact with the lead-out terminal portion 2 across the through hole 4. Then, of the parts where the two are in contact with each other, the welding heat is concentrated on the contact part at the edge of the through hole 4 having a large resistance, and the two are melted at this part.

That is, as shown in FIGS. 1 and 2, the lead-out terminal portion 2 and the extension terminal 3 have welding nuggets 8 and 8 at two positions on both sides of the through hole 4. This embodiment is stronger than the conventional one-point welding obtained by simple spot welding, and is stronger against the force in the horizontal rotational direction indicated by arrow B in FIG.

[0015]

[Effect of device]

 According to the present invention, since the extension terminal with solder is overlapped and welded to the through hole provided in the lead-out terminal portion, the following effects can be obtained. (1) Since the solder is fixed in the through hole, the extension terminal is firmly joined to the lead-out terminal portion by the wedge effect. Therefore, even if the diameter of the extension terminal varies, the strength can be maintained within the range of acceptable products.

(2) Since the welding is performed with a spread along the edge of the through hole, sufficient strength can be obtained against the force in the direction of rotation in the plane including both terminals.

(3) Since the melted solder enters the through hole, the occurrence of a solder burr is eliminated. Therefore, the insulation failure between the lead terminals and the insulation failure of the PCB will not occur.

[Brief description of drawings]

FIG. 1 is an enlarged plan view of a main part in one embodiment.

FIG. 2 is a cross-sectional view taken along the line CC of FIG.

FIG. 3 is a sectional view of a display tube according to an embodiment.

[Explanation of symbols]

 1 Display tube 2 Lead-out terminal part 3 Extension terminal 4 Through hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Masafumi Hasegawa 629 Oshiba, Mobara-shi, Chiba Futaba Electronics Co., Ltd.

Claims (2)

[Scope of utility model registration request] 1. A display tube, which has a lead-out terminal portion led out from the inside of the display tube and provided with a through hole at one end, and an extension terminal welded to an edge portion of the through-hole of the lead-out terminal portion. External terminal. 2. The extension terminal has a solder plating layer on the surface, and the through hole is filled with the solder layer and joined.
External terminal of the indicated display tube.