JPS6035778B2 - Manufacturing method for airtight terminals - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a method of manufacturing an airtight terminal, particularly an airtight terminal having a long glass tube integrally formed under a sealing glass.

As shown in FIG. 1, in order to increase the creepage distance between the lead wire 1 and the metal outer ring 2, a spherical sealing glass 4 having an integrally long glass tube 3 at the bottom is used to connect the lead wire 1 to the metal outer ring 2. Conventionally, the airtight terminal a, which has a structure sealed to the center of the ring 2, is manufactured one by one using a device as shown in FIG.

That is, a metal outer ring 2' and a glass tube 3' are prepared separately.
Also, the lead wire 1' is placed at a predetermined position in a single-seat bath fixture 8 made of stainless steel or the like having a recess 5, an annular groove 6, and a center hole 7, and a lead wire is inserted on the metal outer ring 2 and on the glass tube 3'. Replace the glass tubes 9, 9' with a central hole, and heat only the glass tubes 9, 9' from the top with a burner to thermally separate the glass tubes 3', metal outer ring 2', and lead wire 1'. It is sealed in one piece. The reason why only the glass tubes 9, 9' are heated and melted using the single bath odor 8 is as follows. That is, the lead wire 1' and the metal outer ring 2' are currently made of an iron, nickel, and cobalt alloy called Kovar (Q=47
x10-7), and the glass tubes 3' and 9,9'' are made of borosilicate glass (Q = 46 x 10-7). Similar to the sealing jig, the outer cylinder part and core part of the glass tube 3' are made of the same material, graphite (Q=40×10-
7) When the glass is isolated and sealed by heating the entire pick-up using a sealing odor-picking device consisting of It is important to provide a gap between the glass tube 3' and the core part, as the gap between the two will become larger and larger at high temperatures during glass sealing, and the positioning of the glass tube 3' by the core part and the On the other hand, if you try to prevent the formation of a gap between the glass tube 3' and the core part at high temperatures, it is necessary to insert the core part into the glass tube 3' at room temperature. However, even if it could be inserted, the glass tube part would not come out from the core part of the jig after cooling and hardening, and in the end, the glass tube 3' would not be able to be fixed in the specified position with the jig.
Since deformation cannot be prevented, only the glass tubes 9 and 9' are heated by the single-seat bath fixture 8.
As described above, it takes time and effort to produce the airtight terminals one by one, which causes an increase in costs. The present invention has been made to improve and eliminate the above-mentioned conventional drawbacks, and embodiments of the present invention will be described below with reference to the drawings.

Figure 3 is a sectional view of the main parts showing the assembled state before the glass is fused and sealed.
an outer cylinder part 11 having a recess 12 into which a ``" can be inserted, a plurality of center holes 13 at the bottom of the recess 12, a core part 14 inserted into the center hole 13 of the outer cylinder part 11, and a core part 14 inserted into the center hole 13 of the outer cylinder part 11; The bottom plate part 15 prevents the child part 14 from falling off.

The outer cylinder portion 11 and the bottomed portion 15 are made of graphite (Q,
= 40 x 10-7), and the center portion 14 has a larger expansion coefficient Q than the glass tube 3'' (Q2 = 46 x 10-7).
3, and has a stepped portion 16 for supporting the glass tube 3'', and a center hole 17 into which the lj code wire 1'' is inserted. Inner recess 1 of center hole 13 of outer cylinder portion 11 and core portion 1
4, the outer diameter 2 below the step 16 and the outer diameter 3 above the step 16 are JI>small 2>? 3, the inner wall surface of the center hole 13 of the outer cylinder part 11 and the core part 14
An annular groove 18 is formed between the stepped portion 16 and the outer wall surface above. The material of the core part 14 can be, for example, graphite mixed with about 5% copper (Q = 200 × 10-7) (〇3≠48 × 10-7). The expansion coefficient Q3 of 14 is made larger than the expansion coefficient (Q2; 46 x 10-7) of glass tube 3''.
Is the outer diameter inside the annular groove 18? 4. What is the inner diameter? 5 glass tubes 3″
Since we insert JI>? 4>J2>J5>G3. Moreover, the inner recess 1 of the center hole 13 of the outer cylinder portion 11
and the difference between the outer recess 4 of the glass tube 3'' (Me1-Me4) and the difference between the inner recess 5 of the glass tube 3'' and the outer recess 3 of the central portion 14 (?5-me?3) are set so that there is no gap between them at high temperatures when glass is fused and sealed.
Reference numeral 19 denotes an upper pick-up tool made of graphite and having a recess 20 for receiving a glass tablet 22 which is recast at the position of the lower jig 10, and a hole 21 into which a protrusion of the lead wire 1'' is inserted.

In the above structure, the glass tube 3'', the metal outer ring 2'', the lead wire 1'' and the glass tablet 22 are arranged at predetermined positions of the lower jig 10, and the upper lining 19 is placed above it, and the whole is assembled. Approximately 9 in a neutral or weakly reducing atmosphere
When heated to about 50 to 1050[deg.] C., the members disposed in the lower jig 10 and the upper jig 19 expand according to their respective expansion coefficients due to the heat. At this time, the lower picking tool 10
Since the expansion coefficients Q, , Q2, and Q3 of the outer cylinder portion 11, glass tube 3'', and core portion 14 and their respective dimensional relationships are set as described above, as shown in FIG.
The gaps between the inner wall surface of the center hole 13 of the outer cylinder portion 11 and the outer wall surface of the glass tube 3'' and between the inner wall surface of the glass tube 3'' and the outer wall surface of the core portion 14 disappear, and the glass tube 3'' This prevents the glass tube 3'' from shifting or deforming. - On the other hand, the glass tablet 22 placed in the jig is melted and welded to the glass tube 3'', lead wire 1'' and metal outer ring 2'' to form an airtight terminal. , each member contracts and returns to its original state.For this reason, there is a gap between the inner wall surface of the center hole 13 of the outer cylinder portion 11 and the outer wall surface of the glass tube 3'', and between the inner wall surface of the glass tube 3'' and the core portion 1.
Since a gap is again formed between the outer wall surfaces of 4, the airtight terminal can be taken out from the lower jig 10 without any problem.
As explained above, the present invention uses a sealing sleeve in which a core part is inserted into the center hole of an outer cylinder part and has an annular groove between the two, a glass tube is inserted into the annular groove, and a core part is inserted into the center hole of the outer cylinder part. The expansion coefficients Q, , Q2, and Q3 of the tube, glass tube, and core portion are set to the relationship Q, < Q2 < Q3, and the inner diameter of the center hole of the outer cylinder portion, the outer diameter and inner diameter of the glass tube, and the center The outer diameter of the parts is set so that there is no gap between them at the glass sealing temperature, and the entire glass is heated to fuse and seal the glass, so there is a long part at the bottom of the sealing glass. It becomes possible to manufacture a large number of airtight terminals that have glass tubes of about 300 mm in length integrally at one time, and the cost can be significantly reduced compared to the method of producing them one by one as in the case of secondary terminals.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an airtight terminal to be manufactured according to the present invention, Fig. 2 is a sectional view of a sealing pick before glass fusion sealing for explaining the conventional manufacturing method, Figs. FIG. 4 is a sectional view of a main part of the sealing finger before and during glass fusion sealing for explaining the manufacturing method of the present invention. a...Airtight terminal with a long glass tube integrated under the sealing glass, 1,1''...Lead wire, 2,2''
...Metal outer ring, 3,3''...Glass tube, 4
... Sealing glass, 10 ... Lower jig, 11
・・・・・・Outer cylinder part, 13 ・・・Center hole, 14
... Core part, 15 ... Bottom slope part, 1
8... Annular groove, 22... Glass tablet, M1... Inner diameter of center hole 13, M3...
... Outer diameter of the core portion 14, G4... Outer diameter of the glass tube 3'', Me5... Inner diameter of the glass tube 3''. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. When manufacturing an airtight terminal in which a lead wire is hermetically sealed to a metal outer ring via a sealing glass and has a glass tube integrally sealed to the sealing glass, the center hole of the outer cylinder portion is Using a sealing jig having an annular structure between them, a glass tube is inserted into the annular groove, and each expansion coefficient α_1,
α_2 and α_3 are set to have an opening relationship of α_1<α_2<α_3, and the inner diameter of the center hole of the outer cylinder portion, the outer diameter of the glass tube, and the inner diameter and outer diameter of the core portion are set to each other at the glass sealing temperature. A method for manufacturing an airtight terminal, which is characterized by heating the entire terminal and sealing the glass in a separate manner so that there is no gap between the terminals.