JP2774746B2 - Manufacturing method of metal vacuum double container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal vacuum double container such as a portable thermos, a pot, a jar and the like, which is manufactured by vacuum sealing without using a sealing member such as a sealing plate. The present invention relates to a method for manufacturing a metal vacuum double container.

[0002]

2. Description of the Related Art FIG. 8 is a view for explaining an example of a conventional method for manufacturing a metal vacuum double container, and shows a state before vacuum sealing of a metal vacuum double container. The container before the vacuum sealing includes a cylindrical inner bottle 1 having a bottom and an outer bottle 4 including a cylindrical outer bottle body 2 and an outer bottle bottom 3. The outer bottle body 2 has its mouth sealed to the mouth of the inner bottle 1 and the outer bottle bottom 3 sealed to the opening end opposite to the mouth of the outer bottle body 2. Is joined to. A concave portion 6 is formed at a substantially central portion of the outer bottle bottom portion 3, and is recessed toward the inner bottle 1. Further, a substantially central portion of the concave portion 6 communicates with a gap 5 between the inner bottle 1 and the outer bottle 4. A small hole (exhaust hole) 7 or a slit for exhaust is formed.

In order to manufacture a metal vacuum double container by vacuum-sealing the container before sealing, the opening of the container before sealing is turned downward, and a metal brazing material or the like is placed in the recess 6. The sealing melting material 8 in paste form is placed in a vacuum heating furnace, and the sealing heating material 8 is heated and melted while evacuating the vacuum heating furnace to a predetermined degree of vacuum. The molten sealing material 8 flows into the exhaust hole 7 from around the exhaust hole 7 and closes the exhaust hole 7. Thereafter, the sealing material 8 is cooled and solidified, and the exhaust hole 7 is vacuum-sealed to produce a metal vacuum double container having a vacuum heat insulating layer between the inner bottle 1 and the outer bottle 4. -26837).

[0004]

However, in this conventional sealing method, a paste-like sealing material 8 is arranged around the concave portion 6, and the sealing material 8 is melted at the time of vacuum sealing, and this is exhausted. the exhaust hole 7 by flowing along the slope of the recess 6 provided in the hole 7 intended for sealing, the amount of sealing welding material 8,
The flow of the molten sealing material 8 changes depending on the inclination and the surface state of the outer cylinder bottom 3 and the concave portion 6, and the inflow into the exhaust hole 7 becomes unstable, resulting in insufficient sealing. Was. Furthermore, in order to prevent these inconveniences, it is necessary to use an unnecessarily large amount of the sealing solvent 8, and there is a problem that the manufacturing cost of the container is increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a sealing material for sealing an exhaust hole reliably captures the exhaust hole so that the sealing material can reliably seal the exhaust hole. It aims to provide a method for manufacturing a metal vacuum double container.

[0006]

In order to solve the above-mentioned problems, a method for manufacturing a metallic vacuum double container according to the present invention is characterized in that a metal inner container and an outer container are integrally joined at respective mouths. A concave portion is formed in either the inner container or the outer container, and an exhaust hole for vacuum exhaust is formed in the concave portion to form a pre-sealing container, and a position vertically above the exhaust hole during vacuum heating. exhaust holes and keep the gap arranged solid sealing welding material and then placed before sealing the container in a vacuum heating furnace, a predetermined degree of vacuum in the gap between the inner container and the outer container through the exhaust holes the heated sealing welding material melts and the molten sealing soluble material sealing welding material which is melted in an exhaust hole and the exhaust hole is dropped directly on its periphery near to solidify it while evacuated to It is characterized by performing vacuum sealing.

[0007]

[Function] A pre-sealing container in which a solid sealing material is disposed with a gap at a position vertically above the exhaust hole at the time of vacuum heating is installed in a vacuum heating furnace, and a gap between the inner container and the outer container is provided through the exhaust hole. The inside is evacuated to a predetermined degree of vacuum and the sealing material is heated and melted, and the molten sealing material is dropped directly to the exhaust hole and the vicinity thereof to fill the exhaust hole with the molten sealing material, By solidifying this and performing vacuum sealing, it is possible to perform vacuum sealing more reliably than the conventional method of vacuum sealing by flowing molten sealing material,
The incidence of defective vacuum sealing is reduced, and the yield of products can be improved. In addition, since the molten sealing material is directly dropped into the exhaust hole and vacuum-sealed, there is no sealing failure such as the exhaust hole cannot be completely closed due to the surface tension of the sealing material, and the amount of the sealing material used is reduced. Thus, the cost can be reduced, and the cost of the product can be reduced.

[0008]

1 to 4 show one embodiment of a method of manufacturing a metal vacuum double container according to the present invention. In the method of manufacturing a metal vacuum double container according to the present embodiment, first, a container (hereinafter, referred to as a pre-sealing container 10) in a state before vacuum sealing shown in FIGS. 1 to 3 is manufactured. The pre-sealing container 10 is formed by joining a bottomed cylindrical metal inner bottle 11 and a bottomed cylindrical metal outer bottle 14 at the mouth.
The outer bottle body 12 has a shoulder portion 19 whose diameter is gradually reduced toward the mouth near the outer end of the mouth.
And an outer bottle bottom 13 hermetically joined to the opening of the outer bottle body 12 opposite to the mouth. As a metal material constituting the inner bottle 11 and the outer bottle 14, stainless steel is particularly preferably used.

At the approximate center of the outer bottle bottom 13, the inner bottle 1
A hemispherical recess 16 is provided on one side. The diameter Do of the concave portion 16 is preferably about 3 to 15 mm. An exhaust hole 17 formed of a small hole having a hole diameter A of about 0.1 to 2 mm is formed at a substantially central portion of the concave portion 16. In addition, a cylindrical solid sealing material 18 is arranged in the recess 16. The diameter d of the solid sealing material 18 is 0.3 to 3 mm.
The degree is desirable, and the length L is in the range of A <L <Do. This solid sealing material 18 has an exhaust hole 17 and a gap in the concave portion 16 so as to be located vertically above the exhaust hole 17 in a state where the pre-sealing container 10 is vacuum-heated, that is, in a state in which the container opening is downward. Be attached.

Next, the pre-sealing container 10 is vacuum-sealed to produce a metal double container. Container 10 before sealing described above
Is stored in a vacuum heating furnace with the mouth facing down,
A vacuum heating process is performed. That is, first, at a temperature equal to or lower than the melting point of the sealing material 18,
Is evacuated to a predetermined degree of vacuum, and then heated to a temperature equal to or higher than the melting point of the sealing material 18 to melt the sealing material 18,
The molten sealing material 18 is dropped into the exhaust hole 17 located vertically below and the vicinity thereof. The exhaust hole 17 and the sealing material 18 that has fallen in the vicinity of the exhaust hole 17 accumulate on the exhaust hole 17 and enter the exhaust hole 17 by capillary action, and then solidify the exhaust hole 17 by cooling and solidifying. FIG. 4 shows a state in which the exhaust hole 17 is sealed with the sealing material 18 in this manner.

If the hole diameter A of the exhaust hole 17 is smaller than 0.1 mm, the exhaust of the gap 15 becomes insufficient, which is not preferable.
On the other hand, if it is larger than 2.0 mm, it may not be able to be completely closed by the surface tension of the molten sealing material 18. Further, as the sealing material 18, a metal brazing material, a low-temperature molten glass, or the like can be used as long as it is solid.

As described above, a metal vacuum double container comprising the metal inner bottle 11 and the outer bottle 14 and having the vacuum heat insulating layer formed between the inner bottle 11 and the outer bottle 14 is manufactured. .
In this embodiment, the pre-sealing container 10 is vacuum-heated,
In other words, with the container opening facing downward, the exhaust hole 17
Cylindrical solid sealing material 18 so as to be positioned vertically above
The pre-sealing vessel 10 is placed in a vacuum heating furnace, and the gap 15 is first evacuated through the exhaust hole 17 at a temperature equal to or lower than the melting point of the sealing material 18 to thereby obtain a predetermined vacuum. Then, the temperature is raised to a temperature equal to or higher than the melting point of the sealing material 18, the sealing material 18 is melted, and the exhaust hole 17 located vertically below the sealing material 18 and the sealing material 18 melted in the vicinity thereof are separated by their own weight. By performing the vacuum sealing by dropping, it is possible to perform the vacuum sealing more reliably than the conventional method of performing the vacuum sealing by flowing the paste-like molten sealing material, and the rate of occurrence of defective vacuum sealing is reduced. And the product yield can be improved. In addition, since the molten sealing material 18 is directly dropped into the exhaust hole 17 and vacuum-sealed, sealing defects such as the exhaust hole cannot be completely closed due to the surface tension of the sealing material 18 are eliminated. Can be reduced, and product cost can be reduced.

In the present invention, the place where the recess 16 is provided is not limited to the outer bottle bottom 13 described above.
For example, the shoulder portion 19 of the outer bottle body 12 as in the embodiment described later.
Or in the inner bottle 11. The bottom of the concave portion 16 is flat as well as the curved concave portion as in the above embodiment.
It may be an inclined one. Further, the shape of the exhaust hole 17 formed in the concave portion 16 may be a slit-like long hole or a small hole, and the position where the exhaust hole 17 is formed in the concave portion 16 may be a concave portion. It is not limited to the approximate center of 16 but may be near the periphery. Further, the shape of the solid sealing material 18 is not limited to a column, and the length is equal to or larger than the diameter of the exhaust hole 17 and has a shape that does not hinder the evacuation when disposed vertically above the exhaust hole 17. Any solid may be used. The volume of the sealing material 18 is not limited to the volume calculated from the dimensions shown above, and the diameter twice as large as the smallest one of the above-described exhaust holes 17 is at least 0.1 m.
m that can be covered with a thickness of m
What is necessary is just to set the maximum value to a value that does not exceed the volume in the concave portion so that the external impact is not locally concentrated.

FIGS. 5 to 7 show another embodiment of the method for manufacturing a metal vacuum double container according to the present invention. The difference between the pre-sealing container 20 used in this embodiment and the pre-sealing container 10 used in the previous embodiment is that the outer bottle body 12 has a shoulder 1.
9, a pocket-shaped concave portion 21 is formed, a small hole-shaped exhaust hole 22 is formed in the concave portion 21, and a column-shaped sealing solution 18 is mounted vertically above the exhaust hole 22.

In the pre-sealing container 20, the solid sealing material 18 is positioned vertically above the exhaust hole 22 with a gap therebetween in an upright state. In order to perform the shutting, the pre-sealing container 20 is placed in a vacuum heating furnace in an upright state, that is, with the container opening facing upward, and then a vacuum heating process is performed. In this vacuum heating process, the gap 15 is first evacuated to a predetermined degree of vacuum through the exhaust hole 22 at a temperature equal to or lower than the melting point of the sealing solvent 18,
The temperature is raised to a temperature equal to or higher than the melting point of the sealing material 18 and the sealing material 1
8 is melted, and the melted sealing material 18 is dropped into the exhaust hole 22 located vertically below the melt hole 8 and the vicinity thereof. Exhaust hole 2
2 and the sealing material 18 dropped in the vicinity thereof accumulate on the exhaust hole 22 and enter the exhaust hole 22 by capillary action.
Thereafter, the exhaust hole 22 is securely sealed by cooling and solidifying.

In the manufacturing method according to this embodiment, the same effects as those of the previous embodiment can be obtained.
Can be installed in a vacuum heating furnace with the opening of the container facing up, so that a jig for supporting the container before sealing in the vacuum heating furnace is not required, and the loading and unloading operation of the container during vacuum heating Becomes easier.

[0017]

As described above, according to the method for manufacturing a metal vacuum double container of the present invention, the metal inner container and the outer container are integrally joined at their respective mouths, A concave portion is formed in one of the outer containers, and an exhaust hole for evacuation is formed in the concave portion to form a pre-sealing container, and a solid is formed with a gap at a position vertically above the exhaust hole during vacuum heating. Is placed in a vacuum heating furnace, and the space between the inner container and the outer container is evacuated to a predetermined degree of vacuum through the exhaust hole, and the sealing material is placed. By heating and melting the molten sealing material, the molten sealing material is dropped directly into the exhaust hole and its surroundings, filled with the molten sealing material in the exhaust hole, solidified, and vacuum sealed. It is a method of vacuum sealing by flowing molten sealing material It can also reliably can perform vacuum sealing, the incidence of vacuum seal failure to improve the yield of products decreases. In addition, since the molten sealing material is dropped directly into the exhaust hole to perform vacuum sealing, sealing defects such as the exhaust hole cannot be completely closed due to the surface tension of the sealing material are eliminated. Can be reduced, and product cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a pre-sealed container showing one embodiment of the present invention.

FIG. 2 is a bottom view of the same pre-sealing container.

FIG. 3 is a sectional view of a main part of the same pre-sealing container.

FIG. 4 is a sectional view of a main part showing a state after vacuum sealing of the same container.

FIG. 5 is a front sectional view of a pre-sealed container showing another embodiment of the present invention.

FIG. 6 is a front view of a main part of the same pre-sealing container.

FIG. 7 is a sectional view of a main part of the same pre-sealing container.

FIG. 8 is a front sectional view of a pre-sealed container showing an example of a conventional method for manufacturing a metal vacuum double container.

[Explanation of symbols]

10, 20 ... container before sealing, 11 ... inner bottle (inner container) 1
2 ... outer bottle body, 13 ... outer bottle bottom, 14 ... outer bottle (outer container), 15 ... void, 16, 21 ... concave, 17,
22 ... exhaust hole, 18 ... solid sealing molten material, 19 ... shoulder.

Continued on the front page (72) Inventor Eiji Otsuka 1-16-7 Nishi-Shimbashi, Minato-ku, Tokyo Inside Nippon Sanso Co., Ltd. (72) Inventor Toshimitsu 1-7-17 Nishi-Shimbashi, Minato-ku, Tokyo Japan Oxygen Stock In-company (56) References JP-A-3-66332 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) A47J 41/02

Claims (1)

(57) [Claims] 1. A metal inner container and an outer container are integrally joined at their respective mouths, and a concave portion is formed in one of the inner container and the outer container, and an evacuation pump is provided in the concave portion. A hole is formed to form a pre-sealing container, and a gap is maintained between the exhaust hole and the vertical position above the exhaust hole during vacuum heating.
Then, the solid sealing material is placed, and then the pre-sealing container is placed in a vacuum heating furnace, and the space between the inner container and the outer container is evacuated to a predetermined degree of vacuum through the exhaust hole, and the sealing is performed. Heat-melting material is melted by heating, and the molten sealing material is dropped directly into the exhaust hole and its surroundings, and is melt-sealed in the exhaust hole.
Filled with dissolved material, method for producing a metal-made vacuum double container which is characterized in that the vacuum seal by solidifying it.