JPH0314110Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a metal vacuum double container, and particularly relates to a mounting structure for a vacuum exhaust pipe.

[Conventional technology]

In a metal vacuum double container used for a metal thermos bottle, etc., a vacuum exhaust pipe 21 is attached to the body bottom member 20 of the outer container as shown in FIG. 4 in order to exhaust air between the double containers. be. Trunk bottom member 20
is made of stainless steel or other iron alloy, and has a mounting hole 22 in its bottom surface, and a peripheral edge 23 of the mounting hole 22 protrudes outward. The vacuum exhaust pipe 21 inserted into the above-mentioned mounting hole 22 is made of copper or copper alloy, and a brazing material 2 is placed around it in advance.
4 is attached and inserted into the mounting hole 22, and then integrated with the protruding end of the peripheral edge 23 by brazing.

The vacuum exhaust pipe 21 is made of copper or a copper alloy because the tip is compressed flat and tightly cut after the vacuum is drawn, and the body bottom member 20 is made of copper or a copper alloy. Stainless steel or iron alloys are used.

Therefore, the part where they are joined together is a joint of dissimilar metals, and the joint part is the end of the periphery on the mounting hole 22 side, but the vacuum exhaust pipe 21
Conventionally, joining by brazing has been performed because joining by welding does not provide sufficient airtightness since the side is the peripheral surface.

[Problem that the invention attempts to solve]

However, joining by brazing requires many steps and cleaning work to remove flux, and the use of a brazing material (silver solder) is one of the causes of increased manufacturing costs. Furthermore, in order to ensure the required strength and ensure airtightness, the mounting holes 22
The gap between the vacuum exhaust pipe 21 and the vacuum exhaust pipe 21 required strict dimensional accuracy.

Therefore, the purpose of this invention is to improve the connection structure between the body bottom member 20 and the vacuum exhaust pipe 21 so that a reliable connection can be achieved by welding.

[Means for solving problems]

In order to solve the above-mentioned problems, this invention makes the periphery of the vacuum exhaust pipe mounting hole provided in the body bottom member protrude inward, and the end face of the vacuum exhaust pipe inserted from the outside into the mounting hole is attached to the periphery. The end faces are integrated by welding to match the end faces of.

〔Example〕

FIG. 1 shows an example in which the metal vacuum double container 1 of this invention is used as a thermos bottle. This vacuum double container 1 consists of an inner container 2 and an outer container 3, with a vacuum insulation space 4 formed between both containers 2 and 3. The outer container 3 has a shoulder member 5 and a body bottom member 6, and a vacuum exhaust pipe 7 is attached to the body bottom member 6.

This evacuation pipe 7 is compressed and tightly cut after evacuation.

The above-mentioned vacuum exhaust pipe 7 is made of copper or copper alloy as in the past, and the body bottom member 6 is also made of stainless steel or iron alloy as in the past.

As shown in FIG. 2, the peripheral edge 9 of the mounting hole 8 formed in the body bottom member 6 protrudes inward, and the inner circumferential surface of the tip of the evacuation pipe 7 inserted into the mounting hole 8 is It is formed into a tapered surface 10 whose inner diameter increases toward the tip, and the thickness of the end surface 11 is formed to be substantially equal to the thickness of the end surface 12 of the peripheral edge 9 of the attachment hole 8 .

The above end surfaces 11 and 12 are aligned so that they are on the same plane as shown in FIG.
are applied and integrated. Welding methods include Teig welding, plasma welding, MIG welding, and the like.

Tapered surface 1 formed at the tip of the vacuum exhaust pipe 7
0 is for making the thickness of the circumferential edge 9 of the mounting hole 8 the same and balancing the heat conduction during welding. Therefore, if both thicknesses are equal or substantially equal, there is no need to form the tapered surface 10.

In addition to forming the tapered surface 10 as described above, a method for aligning the wall thickness of the tip of the vacuum exhaust pipe 7 with the thickness of the peripheral edge 9 of the mounting hole 8 is to create a uniformly thin walled portion at the tip by cutting. There is also a way to form.

[Effect of idea]

As described above, this invention connects the end face of the mounting hole to the end face of the vacuum exhaust pipe by welding by making the peripheral edge of the mounting hole protrude inward, thereby achieving a highly airtight joint. be able to.

In addition, since there is no need for brazing filler metal or flux, costs can be reduced, and there is no need for a flux cleaning process.Furthermore, the dimensional accuracy between the mounting hole and the vacuum exhaust pipe is not required to be as strict as shown above, making manufacturing easier. becomes easier.

In addition, a certain distance or more is required between the joint and the cutting position so that the stress when cutting vacuum exhaust pipes under compression does not affect the joint. Since it is closer to the inside of the body bottom member, the dimension from the bottom of the body bottom member to the compression tight cut of the vacuum exhaust pipe can be shortened.
It also has the effect of lowering the height of the container.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the embodiment, Fig. 2 is an exploded sectional view of the bottom member and vacuum exhaust pipe, Fig. 3 is an enlarged sectional view of the joined state in Fig. 2, and Fig. 4 is an exploded sectional view of the conventional example. It is a diagram. 1... Vacuum double container, 2... Inner container, 3... Outer container, 4... Vacuum insulation space, 6... Body bottom member, 7
...Vacuum exhaust pipe, 8...Mounting hole, 9...Periphery, 1
0... Tapered surface, 11, 12... End surface, 13...
welding.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A metal vacuum double container consisting of a combination of an inner container and an outer container, with a vacuum exhaust pipe attached to the bottom member of the outer container, which is provided on the bottom member of the outer container. The periphery of the vacuum exhaust pipe mounting hole is made to protrude inward, the end face of the vacuum exhaust pipe inserted into the mounting hole from the outside is aligned with the end face of the periphery, and the end faces are integrated by welding. Metal vacuum double container. (2) The utility model according to claim 1, characterized in that the tube wall thickness at the insertion side end of the vacuum exhaust tube is formed to be substantially equal to the thickness of the end surface around the periphery of the mounting hole. Metal vacuum double container.