JPS6329296Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a structure of an airtight terminal base of a crystal resonator, and more particularly to a structure for attaching an earth lead by silver brazing to an airtight terminal base of a crystal resonator.

When attaching the ground lead to the airtight terminal base of the crystal resonator, it is desired that the ground lead be securely attached with high fixing strength to prevent the ground lead from coming off. Conventionally, ground leads have been attached using silver brazing or spot welding, but in general, spot welding tends to cause variations in welding quality due to fluctuations in welding conditions, and the ground lead may be damaged due to weld peeling. Defects that come off may occur. On the other hand, in the case of silver brazing, there is no such unstable element and the earth lead can be attached stably.

By the way, when silver solder is used, the reliability of the attachment of the earth lead is high, but on the other hand, expensive silver solder must be used, which is a problem that it is a factor in increasing the manufacturing cost of the product.

That is, FIG. 3 shows a structure for attaching the earth lead by silver brazing to the airtight terminal base of a conventional crystal resonator. Hole 12 is a ground lead sealing hole 11, and a ground lead 1 passes vertically through the metal base 10.
Reference numeral 3 denotes silver solder which fills the earth lead sealing hole 11 and fixes the earth lead 12 to the metal base 10. Here, the hole diameter of the earth lead sealing hole 11 is:
Since the silver solder 13 is expensive, it is desirable to make the diameter as small as possible in order to reduce its usage as much as possible, but the metal base 10 serves as a base to support the whole, and a relatively thick plate is used. Therefore, it is difficult to make a very small diameter hole by press processing due to the strength of the press die, and in the end, depending on the thickness of the metal base 10, it is necessary to make a hole with a diameter that is larger than necessary compared to the wire diameter of the ground lead 12. However, there is a problem in that the internal volume of the hole becomes large and the amount of silver solder used increases.

In addition, Figures 4 and 5 show the mounting structure of the earth lead using conventional spot welding. Right angle large diameter part 16,1
The large diameter portions 16 and 17 of the inner earth lead 14 and outer earth lead 15 formed with
It is spot welded to the upper and lower surfaces of the metal base 10, and as shown in FIG. The inner earth lead 14 having the large diameter portion 16 is inserted into the hole, and the large diameter portion 16 is spot welded at the recess 18 portion. However, since the mounting structure of these ground leads is spot welded, there are concerns about the reliability of the fixing as mentioned above.In addition, in the case of the one shown in FIG. Since the large-diameter portion 17 of the lead 15 is provided, the metal base 10 is removed by the thickness of the large-diameter portion 17 when mounted on a printed wiring board.
It has the disadvantage that it floats on the board, making it unstable to place.In addition, the one shown in Fig. 5 has a relatively thick metal base 10 with a small diameter ground lead insertion hole 1.
Since it is difficult to drill the hole 9, the recess 18 is first formed and made thinner, and then the ground lead insertion hole 19 is drilled, which has the drawback of increasing the number of pressing steps required for this hole and increasing the manufacturing cost. .

The one in Figure 5 has only an inner ground lead that connects to the ground pole of the crystal resonator, but does not have an outer ground lead that connects to the printed wiring board, and is connected to the metal base 10 or the metal cap that is placed on top of it. This type connects the ground to the printed wiring board using a separate lead wire.

The present invention has been made in view of the above points, and is designed to facilitate the drilling of the earth lead sealing hole in the metal base in the mounting structure of the earth lead by silver brazing on the airtight terminal base of the crystal resonator. To provide a structure of an airtight terminal base for a crystal resonator, which can use an economical amount of solder and can provide a high fixing strength for a ground lead.

Hereinafter, the present invention will be explained with reference to the drawings and examples.

FIG. 1 shows the structure of an airtight terminal base of a crystal resonator according to an embodiment of the present invention. In the figure, 1 is a metal base, and 2 is an earth lead sealing hole made in the metal base 1. The hole diameter of the earth lead sealing hole 2 is determined to be such that it does not place a burden on the press die when drilling the hole, in view of the thickness of the metal base 1. That is, metal base 1
If you try to make the hole diameter of the ground lead sealing hole 2 as small as possible compared to the plate thickness, the pin of the mold for punching this hole with a press will also have a smaller diameter, and this will actually break. Cannot be processed. Therefore, the hole diameter is determined to an extent that does not place a large burden on the press mold. Regarding this point, in comparison with the conventional structure shown in FIG. 3, if the thickness of the metal base 1 and the metal base 10 are the same, the hole diameter of the ground lead sealing hole 11 in FIG. 3 may be the same, and It may be more than that.

3 and 4 are ground leads; specifically, 3 is an inner ground lead whose other end is connected to the ground pole of the crystal resonator, and 4 is an outer ground lead whose other end is connected to the printed wiring board. . These earth leads 3, 4 are provided with large diameter parts 5, 6 having an outer diameter larger than the wire diameter at one end thereof, and the end surfaces of these large diameter parts 5, 6 are formed in a plane perpendicular to the axial direction thereof. . The large diameter portions 5 and 6 can be easily made by press working. Reference numeral 7 denotes a disc-shaped intermediary metal plate having an outer diameter slightly smaller than the diameter of the earth lead sealing hole 2 of the metal base 1 and an appropriate thickness, and its upper and lower surfaces are parallel planes.

These intermediary metal plate 7 and ground leads 3 and 4 are
The end surfaces of the large diameter portions 5, 6 of the earth leads 3, 4 corresponding to the upper and lower surfaces of the intermediary metal plate 7 are aligned and fixed by silver brazing, spot welding, or the like. This intermediary metal plate 7 is connected to the ground lead sealing hole 2.
The large-diameter portions 5 and 6 of the earth leads 3 and 4, which are disposed in the hole 2 at right angles to the axial direction of the metal plate 7 and are fixed to the upper and lower surfaces of the intermediary metal plate 7, are also accommodated in their entirety. In this way, accommodating the intermediary metal plate 7 and the large diameter portions 5, 6 of the earth leads 3, 4 in the earth lead sealing hole 2 of the metal base 1 is particularly important due to the presence of the intermediary metal plate 7. The actual internal volume of the earth lead sealing hole 2 is reduced by that volume.

Reference numeral 8 denotes silver solder which is filled into the earth lead sealing hole 2 of the metal base 1, and is used to braze the intermediary metal plate 7 and one end of the earth leads 3 and 4 to the metal base 1. Here, since the actual internal volume of the earth lead sealing hole 2 of the metal base 1 is reduced mainly due to the presence of the intermediary metal plate 7, as described above, compared to the conventional case shown in FIG. Even if the hole diameter is increased, the internal volume does not increase proportionally; for example, even if the amount of silver solder used is the same as before, the diameter of the intermediary metal plate 7 and the earth leads 3 and 4 will increase. This means that the pore diameter can be increased by an amount equivalent to the volume of the large portions 5 and 6. Conversely, if the hole diameter is the same as in the conventional case, the amount of silver solder 8 used will be reduced by the volume of the intermediary metal plate 7 and the like. Moreover, the large-diameter portions 5 and 6 of the ground leads 3 and 4 are embedded in the silver solder 8, increasing the contact area, so the mounting structure provides sufficient fixing strength even when the amount of silver solder 8 used is reduced. It is becoming.

Next, FIG. 2 shows another embodiment of the present invention. The one shown here is of a type in which only an inner earth lead 3 is provided and no outer earth lead 4 is provided, and its structure is exactly the same as the previous embodiment except that the outer earth lead 4 is not present.

As described above, in the airtight terminal base of the crystal resonator of the present invention, since the intermediary metal plate is embedded in the silver solder filled in the earth lead sealing hole of the metal base, the inner volume of the earth lead sealing hole is used as the intermediary. The amount of silver solder used is reduced by the volume of the metal plate, and from the perspective of the amount of silver solder used, the amount of silver solder used can be reduced by the volume of the intermediary metal plate, so the diameter of the ground lead sealing hole can be increased accordingly. , when making holes by press working on metal bases that use relatively thick metal plates and are therefore difficult to make small diameter holes, the burden on the mold is lightened, making it easier to make holes, making manufacturing easier. It becomes easier. Furthermore, if the diameter of the earth lead sealing hole is not particularly large, the amount of silver solder used can be reduced by the volume of the intermediary metal plate, resulting in economical manufacturing.

Furthermore, since one end of the ground lead has a large diameter part and this is embedded in the silver solder, the contact area with the silver solder at the fixed end of the ground lead is large, and the ground lead can be fixed with high fixing strength. can.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an airtight terminal base of a crystal resonator according to an embodiment of the present invention, and FIG. 2 is a sectional view of an airtight terminal base of a crystal resonator according to another embodiment of the invention.
FIGS. 3 to 5 are cross-sectional views of conventional devices. 1...Metal base, 2...Earth lead sealing hole, 3, 4...Earth lead, 5, 6...Large diameter portion, 7...Intermediate metal plate, 8...Silver solder.

Claims (1)

[Scope of utility model registration request] One end has a large-diameter part with an outer diameter larger than the wire diameter, and the end face of this large-diameter part is a plane whose upper and lower surfaces are parallel to a plane perpendicular to the axial direction of the ground lead. An intermediary metal plate to which the end face of the large-diameter portion of the ground lead is fixed to each of the lower surfaces or the upper surface; The intermediary metal plate is placed in the earth lead sealing hole at right angles to the axial direction of the earth lead sealing hole, and the entire large diameter portion of the earth lead fixed to the intermediary metal plate is accommodated. an airtight terminal for a crystal resonator, comprising: a metal base; and silver solder, which is filled into the earth lead sealing hole of the metal base and fixes the intermediate metal plate and one end of the earth lead to the metal base. base structure.