JPS641910B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hermetic terminal, and more particularly to a small hermetic terminal having a flat glass top surface, on which an element is attached, such as a quartz oscillator holder for a watch.

As shown in Figs. 1 and 2, the watch crystal oscillator is an airtight quartz oscillator in which two lead wires 3, 3 are hermetically and insulatively sealed inside a cylindrical metal outer ring 1 through a glass 2. A crystal resonator 5 is supported on the glass 2 between the lead wires 3 and 3 using the terminal 4, and a metal cap (not shown) is hermetically fixed and sealed to the terminal 4 by means such as press fitting. Here, the mounting surface 2a of the glass 2 for the crystal resonator 5 is required to be a flat surface in order to support the crystal resonator 5 vertically.

By the way, the metal outer ring 1 is generally made by preparing a metal plate 10 of a predetermined thickness (A) and drawing it with a press machine to produce a bottomed cylindrical body 11, as shown in FIG.
(B), the bottom plate portion 11a is punched out with a cutting die 12 to form a through hole 13 (C), and finally the metal plate 10 portion is punched out with a press machine (D). As shown in FIG. 4, the metal outer ring 1 manufactured in this manner has a cut surface 14 on the inner surface of the through hole 13 of about 2/3 of its thickness and a fractured surface of about 1/3 of its thickness. 15, and a burr 16 formed by press punching is formed at the lower end of this fractured surface 15. If such fractured surfaces 15 and burrs 16 exist, glass sealing work becomes difficult, so prior to glass sealing work, a barrel polishing process is performed to form the through hole 1 as shown in FIG.
A curved surface portion 17 is formed at the lower end of 3.

Then, as shown in FIG. 6, this metal outer ring 1
A sealing jig 6 made of graphite with a flat top surface 6a.
A glass tablet 2' is placed on top of the metal outer ring 1, and two lead wires 3, 3 are placed through the glass tablet 2'.
The lower end is connected to the lead wire receiving holes 6b, 6 of the sealing jig 6.
The whole is heated to about 1000°C in a neutral or weakly reducing atmosphere, and the metal outer ring 1 is inserted through the glass 2 in which the glass tablet 2' is melted.
and the lead wires 3, 3 are sealed in an airtight and insulating manner.

However, even if the curved surface part 17 is formed at the lower end of the through hole 13 by barrel polishing as described above, the fractured surface 15 is not completely removed as shown in FIG. It was found that because the molten glass 2 has a rough surface due to processing and the wetting of the molten glass 2 is poor, irregularly shaped minute recesses 7 are likely to be formed around the periphery of the glass 2, as shown in FIG.
If there is such an irregularly shaped minute recess 7,
Not only does the product value decrease in terms of appearance, but processing solutions such as pickling solution and plating solution cannot be completely removed from these minute recesses 7, which not only causes inconveniences such as rusting, but also damages the crystal resonator. There was a problem that it became difficult to support it vertically.

Therefore, the main object of the present invention is to provide an airtight terminal using a metal outer ring having a press-broken surface and/or a barrel-polished surface at the inner end on the element mounting surface side, in which the peripheral edge of the glass on the element mounting surface side The aim is to eliminate the minute recesses in the area.

To summarize the present invention, the glass end face of the element mounting surface having a press fracture surface and/or barrel polishing surface is approximately equal to the total dimension of the press fracture surface and/or barrel polishing surface, rather than the end surface of the metal outer ring. It is characterized by a concave flat surface.

The above objects and other objects and features of the present invention will become more apparent from the following detailed description with reference to the drawings.

FIG. 8 shows a longitudinal sectional view of an assembled state before heat sealing for explaining the method of manufacturing an airtight terminal of the present invention. In the drawings, the same or corresponding parts as in FIGS. 1 to 7 are designated by the same reference numerals, and their explanations will be omitted. The difference from Figure 6 is that
The glass contact surface 61 of the graphite sealing jig 60 that comes into contact with the molten glass is comparable to the total dimension of the press fracture surface and/or barrel polished surface of the metal outer ring 1 than other parts, that is, the metal It is made to protrude by an amount equivalent to 1/3t of the thickness t of the ring 1. The glass contact surface 61 is preferably formed into a smooth surface with a surface roughness of about 0.1 to 10 μm.

In the above configuration, the whole is heated to about 1000° C. in a neutral or slightly reducing atmosphere. Then, the glass tablet 2' is melted, and the metal outer ring 1 and the lead wires 3, 3 are hermetically and insulatively sealed via the glass 2. Here, since the glass contact surface 61 of the sealing jig 60 is protruded from the other parts, the ninth
As shown in the figure, the surface 2a of the glass 2 on which the crystal resonator 5 is attached is a flat surface that is slightly recessed from the metal outer ring 1 and is uniform throughout. Therefore, the crystal resonator 5 can be supported vertically on this surface 2a. Here, the glass contact surface 6 of the sealing jig 60
If 1 is a smooth surface, the surface 2a, which is the mounting surface of the crystal resonator 5, will be a flat and smooth surface.
Furthermore, the crystal resonator 5 can be vertically supported with higher precision.

If necessary, the glass tablet 2' may be attached to the upper sealing jig 7 as shown by the two-dot chain line in FIG.
The glass may be sealed with a pressure of 0. In this case, it is desirable that the glass contact surface 71 of the upper sealing jig 70 has a surface roughness of about 10 to 30 μm, which is rougher than the glass contact surface 61 of the sealing jig 60.

Furthermore, in the above embodiment, the case where the crystal resonator is sealed with the glass with the mounting surface facing downward is explained, but if necessary, the crystal resonator is sealed with the glass with the mounting surface facing upward. You may. In this case, it is of course necessary to make the glass contacting surface of the upper sealing jig protrude more than the other parts.

Furthermore, although the above embodiment describes the case where the metal outer ring 1 is manufactured by press drawing and punching, if necessary, the metal pipe material may be cut and cutting burrs removed by barrel polishing. may also be used.

Also, if necessary, a metal outer ring without barrel polishing after pressing may be used.

As described above, the present invention provides an airtight terminal using a metal outer ring having a press-broken surface and/or a barrel-polished surface. Since the glass end surface is a flat surface that is recessed to an extent equivalent to the total dimension of the press fracture surface and/or barrel polished surface, the glass surface on the element mounting side has minute recesses at the periphery. It is possible to obtain a flat airtight terminal without any cracks, and it is possible to prevent rusting due to incomplete removal of the processing liquid due to the presence of minute recesses.

[Brief explanation of the drawing]

Figure 1 is a plan view of the crystal oscillator holder, Figure 2 is a vertical cross-sectional side view of Figure 1, Figure 3 is a vertical cross-sectional view of each process explaining the method of manufacturing the metal outer ring, and Figure 4 is a cross-sectional view of each process. Figure 5 is an enlarged vertical cross-sectional view of the metal outer ring manufactured by the method shown in Figure 3.
The figure is an enlarged vertical cross-sectional view of a metal outer ring subjected to barrel polishing, FIG. 6 is an enlarged vertical cross-sectional view showing the assembled state before heat sealing to explain the conventional manufacturing method, and FIG.
The figure is an enlarged vertical cross-sectional view of an airtight terminal manufactured by a conventional method, and FIG. 8 is an enlarged vertical cross-sectional view showing an assembled state before heat sealing for explaining one example of the manufacturing method of the airtight terminal of the present invention. FIG. 9 is an enlarged longitudinal sectional view of the airtight terminal of the present invention. 1...Metal outer ring, 2...Glass, 2'...Glass tablet, 2a...Glass end surface, 3, 3...
Lead wire, 4, 40... Airtight terminal, 5... Crystal resonator, 15... Press fracture surface, 17... Barrel polished surface (curved surface part), 60... Sealing jig, 61...
... Glass contact surface, 70 ... Second sealing jig (upper sealing jig), 71 ... Glass contact surface.

Claims (1)

[Scope of Claims] 1. In an airtight terminal in which a lead wire is hermetically and insulatively sealed via glass in a metal outer ring having a press-broken surface and/or a barrel-polished surface at the inner end on the element mounting surface side. , the glass end face on the side of the press fracture surface and/or barrel polishing surface is a flat surface recessed to an extent equivalent to the total dimension of the press fracture surface and/or barrel polishing surface, more than the end surface of the metal outer ring; Features an airtight terminal.