JPS6330133Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a compression-sealed airtight terminal suitable as an airtight cap for rectifiers, thyristors, etc.

The airtight terminal conventionally used as an airtight cap for a general rectifier is, as shown in Fig. A metal inner ring 3 made of an alloy is hermetically and insulatively sealed, and a copper pipe lead 4 having an H-shaped cross section is hermetically fixed to the metal inner ring 3 with silver solder or the like.

However, when the metal outer ring 1 is manufactured by cutting a round bar made of free-cutting steel (SUM) as described above, the round bar has a diameter equal to the outer diameter 1 of the flange portion 1a of the metal outer ring 1. Since there are many parts removed by cutting,
The material utilization rate is poor, and since both the outside and the inside are cut, the cutting process is extremely troublesome, and the metal outer ring 1 becomes expensive. Moreover, when a round bar is machined, there are holes 5 in the direction in which the bar is stretched, that is, in the vertical direction of the metal outer ring 1, so that only an airtight terminal with low airtightness and reliability can be obtained. There was a problem.

Therefore, the present applicant previously proposed an airtight terminal as shown in FIG. This airtight terminal includes a metal outer ring 10, a metal ring 11 made of free-cutting steel having a predetermined height h and thickness t capable of applying a predetermined compressive stress to the glass 2, and a cold-rolled steel plate ( A thin metal cylindrical body 12 having an upper end inwardly folded part 12a and a lower end outwardly folded part 12b press-molded from SPC) is airtightly fixed and integrated with silver solder or copper solder. It is something. Other parts are first
Since it is similar to the figure, the same parts are given the same reference numerals and the explanation thereof will be omitted.

According to the configuration shown in FIG. 2, even if the metal ring 11 is manufactured by cutting a round bar, the diameter of the round bar is
2 may be smaller than the diameter 1 of the round bar required for manufacturing the metal outer ring 1 shown in Figure 1 (2<1), which not only improves the material utilization rate but also requires only boring for the cutting process itself. This makes cutting easier, and the metal outer ring 1
0 becomes cheaper. Moreover, even if there is a cavity 13 penetrating through the metal ring 11 in the height direction, the upper end of the cavity 13 is closed by the upper end inwardly folded part 12a of the metal cylindrical body 12, which improves airtightness and reliability. This has the advantage that a highly airtight terminal can be obtained. In addition, the metal ring 11
When forming by laminating multiple thin metal rings, each thin metal ring can be manufactured by punching cold rolled steel plates etc., which is cheaper than manufacturing by cutting. can.

As mentioned above, the configuration shown in FIG. 2 has many advantages over the configuration shown in FIG. 1, but the metal ring 11 and the metal cylinder 12 are manufactured separately. Since it is brazed, there are still problems with poor material utilization and high processing costs.

This invention was proposed to solve these problems, and is characterized in that the metal outer ring is made up of a cylindrical part made by forging and pressing a cut steel pipe and a flange part.

An embodiment of this invention will be described below with reference to the drawings. In Fig. 3, 20 is a metal outer ring made of an integral piece formed by forging and pressing a steel pipe such as a carbon steel pipe for mechanical structures (STKM), and its upper end is compressed to a predetermined degree against the sealing glass described later. It has a thick wall portion 21 having a thickness necessary to apply stress, and has a flange portion 22 on the outer side of the lower end.
2 has a projection 23 for resistance welding on the lower surface thereof. 24 is a sealing glass made of soda barium glass, soda lime glass, etc., and a metal inner ring 25 made of an iron-nickel alloy is hermetically and insulatively sealed to the metal outer ring 20 through this sealing glass 24. There is. 25 is a pipe lead made of oxygen-free copper with an H-shaped cross section, and the metal inner ring 2 is
5 is airtightly fixed.

The metal outer ring 20 described above is manufactured as follows. First, as shown in Figure 4, the predetermined outer diameter
A steel pipe 200 having a diameter of 3 and an inner diameter of 4 is prepared, and a cut steel pipe 201 is manufactured by cutting the steel pipe 200 to an appropriate height H1. This steel pipe cut pipe 201 may have a nest 202 in the direction in which the steel pipe 200 is drawn. Next, as shown in FIG.
5, lower the main upper punch 33, and then lower the auxiliary upper punch 34.
lower. Then, the upper end of the steel pipe cut pipe 201 is pushed outward by the slope part 33a of the main upper punch 33, and a part of the meat is caused to flow upward by the large diameter part 33b, and then the auxiliary upper punch The outwardly expanded portion is pressed by the punch 34 to produce the metal outer ring 20 as shown in FIG. Next, when the lower punch 32 is raised, the metal outer ring 20 is brought into contact with the die 3 as shown in FIG.
protrudes from the top surface of 1. When the take-out arm 35 is moved in the direction of the arrow in this state, the metal outer ring 20 can be taken out from the forging press 30. Thus, as shown in Figure 8, the outer diameter is 3 and the inner diameter is 4 at the upper end.
It has a thick wall portion 21 with an inner diameter of 5,
A metal outer ring 20 having a height of H2 is obtained, which has a flange portion 22 having an outer diameter of 6 and a welding projection 23 on the lower surface of the flange portion 22.

Note that even if the steel pipe cut pipe 201 has a cavity 202 in the stretching direction of the steel pipe 200 as shown in FIG.
02 is open to the outer periphery of the flange portion 22, and there is no nest 202 that penetrates inside the metal outer ring 20 in the height direction.

As described above, when the metal outer ring 20 is constructed from a one-piece forged and pressed steel pipe, it can be manufactured by cutting a round bar as shown in FIG.
Compared to manufacturing by brazing the metal ring 11 and the metal cylindrical body 12 as shown in the figure, the material utilization rate is approximately 100%, and moreover, only the cutting of the steel pipe and the forging press are required. Therefore, processing is extremely easy,
The metal outer ring and therefore the hermetic terminal are considerably cheaper. Furthermore, even if a cavity 202 were to occur in the stretching direction of the steel pipe, this cavity 202 would have no effect on airtightness and reliability due to the flow of meat during forging presses, so the airtightness and reliability could be improved. A highly airtight terminal can be obtained. Furthermore, steel pipes have greater hardness than free-cutting steel or cold-rolled steel plates, so the wall thickness required to apply a predetermined compressive stress to the sealing glass 24 can be reduced, or pipes with the same wall thickness can be used. Since a greater compressive stress can be applied to the sealing glass 24, an airtight terminal with greater strength can be obtained.

The above embodiment describes an airtight cap for a rectifier in which a metal inner ring 25 is sealed to the upper center of a metal outer ring 20 via a sealing glass 24, and a pipe lead 26 is brazed to the metal inner ring 25. However, a metal inner ring 25 and a small pipe lead made of iron/nickel alloy (not shown) for a gate terminal are attached to a sealed glass 24 at an eccentric position above the metal outer ring 20.
It can also be applied to an airtight cap for a three-terminal thyristor, in which the pipe lead 26 is soldered to the metal inner ring 25. Moreover, a large pipe lead made of iron/nickel alloy may be used instead of the metal inner ring 25 and pipe lead 2b. Furthermore, the metal outer ring is not limited to having a partial thick wall portion 21.

As mentioned above, this invention has a metal outer ring made of a cylindrical part made of a forged pressed steel pipe and a flange part, so compared to conventional ones using free-cutting steel or cold-rolled steel plates, It has a good material utilization rate and is easy to manufacture, making it inexpensive, and it not only provides airtight terminals with high airtightness and reliability, but also has the effect of providing airtight terminals with better characteristics due to its high hardness. .

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an example of a conventional airtight terminal for a rectifier, Fig. 2 is a sectional view of another example of a conventional airtight terminal for a rectifier, and Fig. 3 is a sectional view of an example of an airtight terminal for a rectifier of this invention. 4 to 8 are cross-sectional views of each process for explaining an example of the method for manufacturing the metal outer ring used in this invention. 20...Metal outer ring, 21...Thick walled part, 22...
Flange portion, 24...Sealing glass, 25...Metal inner ring, 26...Pipe lead, 201...Steel pipe cut pipe.

Claims (1)

[Scope of Claim for Utility Model Registration] A compression-sealed airtight terminal in which a lead is hermetically and insulatively sealed within the cylindrical part of a metal outer ring having a cylindrical part and a flange part through a sealing glass, An airtight terminal characterized in that the metal outer ring is formed by integrally forming a cylindrical part obtained by forging and pressing a cut steel pipe and a flange part.