JP3520180B2 - Manufacturing method of vacuum structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a vacuum structure such as a thermos, a vacuum double tube, a vacuum heat insulation panel, a vacuum container and the like.

[0002]

2. Description of the Related Art Conventionally, in a method of manufacturing a vacuum structure, for example, a thermos bottle, first, an inner bottle and an outer bottle are processed and formed as constituent members of the thermos bottle, and these are welded to be assembled into a double container. In this state, the double container is heated to gasify and discharge oil, moisture, gas molecules, etc. adhering to the constituent members during the processing, and the inner bottle is discharged while discharging the gas stored in the constituent members. It is formed by evacuating the space between the outer bottle and the outer bottle.

However, in the above method, since the heating operation and the evacuation operation are simultaneously performed, there is a problem that a long evacuation time is required to evacuate the space between the inner bottle and the outer bottle to a predetermined vacuum degree. there were.

To solve this problem, Japanese Examined Patent Publication No. 63-5
No. 8319, in the state of the constituent members before assembling as the double container, these constituent members are subjected to degassing treatment by heating under vacuum, and then these constituent members are assembled as a double container, and then the double container A manufacturing method is provided in which the container is heated and the space between the inner bottle and the outer bottle is evacuated.

Further, in Japanese Patent Laid-Open No. 1-297022, after assembling as a double container, the space between the inner bottle and the outer bottle is pre-evacuated to a low vacuum degree of about 1 × 10 ^-2 Torr, and then the above-mentioned two bottles are evacuated. Approximately 1 × 10 ^-4 To while heating the heavy container
A manufacturing method for evacuating to a high vacuum level of rr is provided.

[0006]

However, in the former manufacturing method, since the degassing process of each component is performed under vacuum, that is, since the vacuum furnace must be used, the equipment is large. There was an inconvenience of becoming
Further, the vacuum furnace tends to require a predetermined time to achieve a high degree of vacuum inside, which is not preferable in terms of production efficiency. Further, in the latter manufacturing method, the vacuum structure can be formed to a predetermined degree of vacuum, but the time for vacuum evacuation tends to be long if the time for preliminary evacuation is also combined, which is not always necessary in terms of production efficiency. It was not preferable.
Therefore, it is an object of the present invention to shorten the time required to evacuate the vacuum structure and improve the production efficiency.

[0007]

In order to solve the above-mentioned problems, the method for manufacturing a vacuum structure of the present invention comprises assembling the respective constituent members to form a space closed by them, and exhausting this space. In the method for manufacturing a vacuum structure, 100 is formed before the constituent members forming the space are evacuated.
Pre-heating is performed at a temperature of up to 600 ° C., and this pre-heating is performed in a state before the assembling of each of the constituent members, and among the constituent members, the constituent member in which the exhaust hole is formed is formed from other constituent members. Preheating is performed at a high temperature.

Here, when the preheating temperature is lower than 100 ° C., when hot water of 100 ° C. is poured into a vacuum structure consisting of a thermos, the adhered oil is vaporized and the degree of vacuum is increased. Occurs, and if heated to 600 ° C., the oil and the like can be almost completely removed experimentally. Therefore, the temperature is set to 100 to 600 ° C.

In the method for manufacturing the vacuum structure, the preheating can remove the oil, water, gas molecules, etc. adhering to the respective constituent members and the gas occluded in the respective constituent members in advance, so that the structure is closed. The gas component generated when the space is evacuated is reduced, and the evacuation time can be shortened.

In the method for manufacturing the vacuum structure, it is preferable that the constituent member having the exhaust hole is preheated at a temperature higher than the temperature at which the exhaust hole is sealed with a sealing material. With this configuration, it is possible to minimize the generation of gas from the constituent member having the exhaust hole due to the heat of sealing the exhaust hole with the sealing material.

Further, it is preferable that the preheating temperature is set to a temperature at which one of the constituent members becomes sensitive or lower. Further, it is preferable that at least one of the constituent members is made of stainless steel having a sensitization temperature and each constituent member is preheated at a temperature of 100 to 450 ° C. Furthermore, it is preferable that the vacuum structure has a double structure. By doing so, it is possible to reliably prevent the material properties of the manufactured vacuum structure from being transformed.

Further, it is preferable that the preheating is continuously performed through a drying furnace. As described above, by using the drying furnace instead of the vacuum furnace, the double container can be continuously preheated by the conveyor or the like, so that the production efficiency can be improved.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a vacuum structure including a stainless steel thermos bottle 1 manufactured by the manufacturing method of the present invention. The thermos bottle 1 is a vacuum double container composed of an inner bottle 2 and an outer bottle 3, and a space S closed by the inner bottle 2 and the outer bottle 3 is formed.

The inner bottle 2 and the outer bottle 3 are formed by being divided into bottom portions 4 and 5 and body portions 6 and 7.
It is assembled by welding 5, 6 and 7. A metal foil 9 made of copper, aluminum or the like is wound around the outer surface of the inner bottle 2 to prevent radiant heat transfer. The outer bottle 3 is provided with a recess 5a at the center of the bottom 5 and an exhaust hole 10 at the center of the recess 5a. The exhaust hole 10 is made of a sealing material 11 made of a brazing material or the like. It is sealed by. Further, a getter 22 for sorption and removal of gas in order to obtain a high degree of vacuum is attached to the bottom portion 5 through a mounting member.

Next, a first embodiment of the method for manufacturing the thermos bottle 1 will be described. First, as shown in FIG.
In the process, each constituent member 4 for forming the thermos 1
5, 6 and 7 are formed by pressing or the like. And
The bottom part 4 and the body part 6 are assembled by welding etc.
And the metal foil 9 is wrapped around the outer surface of the inner bottle 2. The metal foil 9 may be wrapped around the inner bottle 2 after preheating in the second step described later.

Then, in a second step, the constituent members 4,
Preheat 5, 6, 7, and 9. Specifically, as shown in FIG. 3, the constituent members 4, 5, 6, 7, and 9 are conveyed to the drying furnace 15 by the conveyor 14 for conveyance, and 100 to 6
Preheat at a predetermined temperature within the range of 00 ° C. This preheating vaporizes and removes the oil and the like adhering to each of the constituent members 4, 5, 6, 7, 9 while processing them, and also occludes the constituent members 4, 5, 6, 7, 9 The gas that is being discharged can be discharged.

Here, when the preheating temperature is lower than 100 ° C., when hot water of 100 ° C. is poured into the vacuum structure consisting of a thermos, the adhered oil and the like are vaporized and the degree of vacuum is increased. However, when heated to 600 ° C., the oil and the like can be almost completely removed experimentally. In addition, among the constituent members 4, 5, 6, 7, and 9,
If there is a material formed of a material having a sensitization temperature, it is necessary to preheat the material at a temperature below the sensitization temperature. This is because heating at the sensitization temperature prevents unevenness in the material composition and facilitates intergranular corrosion cracking. Further, in the case where any one of the constituent members 4, 5, 6, 7, and 9 is made of stainless steel having a sensitization temperature, it is possible to preheat within the range of 100 to 450 ° C. preferable. In addition, the third described later
In order to surely prevent the generation of pinholes due to welding in the step, it is more preferable to set the temperature to about 300 ° C. or lower at which an oxide film that inhibits welding is not formed on the stainless steel surface.

Then, in the third step, the getter 22 is attached to a predetermined member of the preheated constituent members 4, 5, 6, 7 (in this embodiment, the bottom portion 5 of the outer bottle 3), and then the above-mentioned respective constituent members are attached. The members 4, 5, 6, 7 are welded together to form a double container. That is, the inner bottle 2 is inserted into the body portion 7 of the outer bottle 3, these mouth portions are welded, and then the bottom portion 5 is welded to the body portion 7.

Then, in the fourth step, the double container is placed inside the vacuum furnace 16 to completely remove oil, water, gas molecules and the like and the occlusion gas adhering to the surface of the double container. The space S between the inner bottle 2 and the outer bottle 3 is evacuated.

When the space S has been exhausted to a predetermined vacuum degree in the fourth step, the bottom portion 5 of the outer bottle 3 is heated and the exhaust hole 10 is sealed with the sealing material 11. Specifically, in this embodiment, as shown in FIG. 4, before attaching the bottom portion 5 of the outer bottle 3 to the body portion 7, a flux is attached to the periphery of the exhaust hole 10 (the inner surface of the recess 5a) in advance. Flux layer 18
Then, a brazing material is welded to the bottom portion 5 from above the flux layer 18 to form a first brazing material layer 19, and the flux exposed from the first brazing material layer 19 is removed. Next, a second brazing material layer 20 made of a solid brazing material of the same quality as the first brazing material layer 19 is attached. Then, the second brazing filler metal layer 20 is heated to be melted, and the brazing filler metal is poured into the exhaust holes 10 to cause the exhaust holes 1 to flow.
0 is sealed.

The method of sealing the exhaust hole 10 is not limited to the above method, and various conventionally known sealing methods can be arbitrarily adopted. Further, the sealing material 11 is not limited to the brazing material, but a brazing material and a sealing plate may be used together, or the exhaust hole 10 may be sealed by base metal welding without using a sealing member.

As described above, in the manufacturing method of the first embodiment, the constituent members 4, 5, 6, 7 are preheated in a state where the constituent members 4, 5, 6, 7 are molded. Therefore, it is possible to remove in advance oils and stored gas adhering to the outer surface of the inner bottle 2 and the inner surface of the outer bottle 3 forming the space S of the thermos bottle 1, and as a result, during vacuum evacuation. The exhaust time can be shortened.

In the manufacturing method of the first embodiment, when the constituent members 4, 5, 6, 7, 9 are preheated in the second step, these constituent members 4, 5, 6, 7, 9
Of the above, the bottom part 5 provided with the exhaust hole 10 of the outer bottle 3
May be preheated at a temperature higher than that of the other constituent members 4, 6, 7, and 9, specifically, at a temperature equal to or higher than the heating temperature at the time of sealing the exhaust hole 10. In this case, since the gas generated when the exhaust hole 10 is sealed can be minimized, the sealing efficiency can be improved and the efficiency for achieving a high degree of vacuum can be improved. You can

FIG. 5 shows a manufacturing method of the second embodiment. This manufacturing method is suitably adopted when preheating is performed with the getter 22 provided in the space S of the vacuum structure such as the thermos bottle 1.

Specifically, first, in the first step, as in the first embodiment, the respective constituent members 4, 5 forming the thermos bottle 1 are formed.
6 and 7 are formed, and the metal foil 9 is also wound around the copper portion 6 of the inner bottle 2.

Then, in the second step, the getter 22 is attached to a predetermined component (in this embodiment, the bottom portion 5 of the outer bottle 3), and each component 4, 5, 6, 7 is welded to form a double layer. Assemble the container. The constituent members may be preheated in advance, as shown in the first embodiment.

Then, in the third step, the double container is removed as shown in FIG.
The double container is preheated by passing through the inside of the drying furnace 15 by the conveyor 14 shown in FIG. In the present embodiment, the preheating temperature is a temperature at which the getter is activated in the atmosphere, for example, about 150 ° C. or lower, and 10
The temperature is 0 ° C or higher.

Then, in a fourth step, the double container is placed in a vacuum furnace 16 or the like, and the space S is evacuated while heating the inside of the furnace. Then, when the predetermined vacuum degree is reached, the exhaust hole 10 of the outer bottle 3 is sealed by the sealing material 11 by the heating.

As described above, in the manufacturing method of the second embodiment, the activation temperature of the getter 22 (for example, 150 ° C.) is obtained with the constituent members 4, 5, 6, 7 assembled to form a double container. ) Since the preheating is performed below, the getter 22 is not activated by preheating but is activated during vacuum exhaust, so that the gas generated in the space S is efficiently removed, and the getter 22 is exhausted to a predetermined vacuum degree. It is possible to shorten the time required to do this.

The method of manufacturing the vacuum structure of the present invention is not limited to the above-mentioned structure. For example, the preheating may be performed in the state of the plate material before processing and forming the constituent members 4, 5, 6, and 7. Further, the vacuum structure manufactured by the manufacturing method is not limited to the thermos, and the same effect can be obtained even when it is adopted when manufacturing a vacuum double tube, a vacuum heat insulating panel, a vacuum container and the like.

The apparatus for evacuating the double container in which the inner bottle 2 and the outer bottle 3 are assembled is not limited to the vacuum furnace 16, and the tip tube 30 is arranged in the exhaust hole 10 as shown in FIG. Adopting various methods such as a conventionally used tip tube method and a method in which the periphery of the exhaust hole 10 is hermetically sealed by an exhaust jig 32 and partially exhausted as shown in FIG. 7. You can

[0032]

As is apparent from the above description, in the method for manufacturing a vacuum structure of the present invention, pre-heating in a drying oven or the like is performed to remove oils and occluded gas that have been attached in advance, before evacuation. Yes, because it is not a preliminary degassing with a vacuum furnace,
The equipment does not increase in size. Further, since it only passes through the inside of the drying furnace, it can be continuously preheated, and the time required to obtain a predetermined degree of vacuum in the space exhausting step can be shortened. Can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a thermos bottle which is a vacuum structure manufactured by a manufacturing method of the present invention.

FIG. 2 is a process explanatory view showing the manufacturing method of the first embodiment.

FIG. 3 is a schematic view showing an example of a production line used for preheating.

FIG. 4 is a cross-sectional view showing an example of a sealing material that seals an exhaust hole.

FIG. 5 is a process explanatory view showing the manufacturing method of the second embodiment.

FIG. 6 is a schematic cross-sectional view showing a modified example of the device for evacuating the space between the inner bottle and the outer bottle.

FIG. 7 is a schematic cross-sectional view showing another modified example of the device for evacuating the space between the inner bottle and the outer bottle.

[Explanation of symbols]

1 ... Thermos (vacuum structure), 2 ... Inner bottle, 3 ... Outer bottle, 4,
5 ... bottom (constituent member), 6, 7 ... trunk (constituent member), 1
0 ... Exhaust hole, 11 ... Sealing material, S ... Space.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mamoru Fujiyama 1-20-5 Tenma, Kita-ku, Osaka-shi, Osaka Inside Zojirushi Mahobin Co., Ltd. (56) Reference JP-A-1-303112 (JP, A) (58) ) Fields surveyed (Int.Cl. ⁷ , DB name) A47J 41/02 102

Claims (6)

(57) [Claims] 1. A method for manufacturing a vacuum structure, comprising assembling each constituent member to form a space closed by the constituent members, and evacuating the space, before evacuating the constituent member forming the space. Preheating is performed at a temperature of 100 to 600 ° C., and this preheating is performed by assembling the above-mentioned constituent members
Perform in the previous state, and remove the
At higher temperature, the components with pores
A method for manufacturing a vacuum structure, characterized by preheating. 2. The vacuum structure according to claim 1, wherein the constituent member having the exhaust hole is preheated at a temperature higher than a temperature at which the exhaust hole is sealed with a sealing material. Manufacturing method. 3. The method for manufacturing a vacuum structure according to claim 1, wherein the preheating temperature is set to be equal to or lower than a temperature at which one of the constituent members becomes sensitive. . 4. At least one of the constituent members is formed of stainless steel having a sensitization temperature, and each constituent member is preheated at a temperature of 100 to 450 ° C. The method for manufacturing a vacuum structure according to. 5. The method for manufacturing a vacuum structure according to claim 1, wherein the vacuum structure has a double structure. 6. The method of manufacturing a vacuum structure according to claim 1, wherein the preheating is continuously performed through a drying furnace.