JPH1147004A - Method for sealing vacuum structural body and its structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability, to shorten the working time and to assure stable quality by surely sealing a discharge hole. SOLUTION: This method for sealing a vacuum structural body (vacuum bottle 1) consists in evacuating a space S formed of component members (an inside bottle 2, an outside bottle 3 and a bottom plate 4) from a discharge hole 6 formed at the component member, then sealing this discharge hole 6 by a sealing member 7A. In such a case, a brazing filler metal arranging part 5 which projects to an outer side from a space side is disposed in the position of the component member where the discharge hole is formed. After a brazing filler metal 8 is fixed and disposed in this brazing filler metal arranging part 5, the sealing member 7A is fixed by the brazing filler metal so as to exist near the discharge hole 6 and this brazing filler metal is melted, by which the sealing member 7A is moved onto the brazing filler metal disposed within the brazing filler metal arranging part 5. The discharge hole 6 is thus sealed by the sealing member 7A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, as a method for sealing a vacuum structure, for example, a thermos bottle composed of a metal inner bottle and an outer bottle, Japanese Patent Publication No.
In 1-1136, a method using a sealing plate is provided. In this sealing method, an exhaust hole is provided in the bottom plate of the outer bottle, and a brazing material is provided around the exhaust hole of the bottom plate on the space side between the inner bottle and the outer bottle, and After the sealing plate is supported, the inner bottle and the outer bottle are assembled to form a double container, and then the double container is placed in a vacuum furnace, whereby the space between the inner bottle and the outer bottle is formed. Is exhausted from the exhaust hole. Thereafter, the inside of the vacuum furnace is heated to a temperature at which the brazing material melts, so that the sealing plate is dropped onto the exhaust holes, and the exhaust holes are sealed.

[0003] Japanese Patent Application Laid-Open No. 7-8395 provides a method of sealing an exhaust hole with a brazing material itself. In this sealing method, the bottom plate side of the outer bottle is directed downward, and a concave portion that protrudes outward from the space side between the inner bottle and the bottom plate is formed on the bottom plate,
An exhaust hole is provided at the bottom of the concave portion, and a spherical solid brazing material is temporarily joined in the concave portion to soften and flow the brazing material to seal the exhaust hole.

[0004]

However, in the former sealing method, there is no means for positioning the brazing material and the sealing plate, and the brazing material and the sealing plate are located on the side of the space between the inner bottle and the outer bottle. Once assembled as a double container, their arrangement cannot be visually confirmed, so that the brazing material and the sealing plate are not sealed with the outer bottle in the state where the double container is formed. When there is a deviation from the bottom plate or a positional deviation occurs, there is a possibility that poor sealing may occur, and the reliability is lacking. In addition, since the brazing material and the sealing member must be carefully handled so as not to be detached from the mounting position before evacuation, workability is not preferable.

In the latter sealing method, as in the former method, there is a possibility that the brazing material may come off in the temporarily joined state of the brazing material, and the brazing material is disposed on the space side. There was a concern that it lacked certainty. Japanese Patent Laid-Open No. 7-8395 discloses an embodiment in which a stopper for preventing the brazing material from dropping is provided in order to solve the above problem. However, in the method of sealing the exhaust hole with the brazing material as described above, when the diameter of the exhaust hole is too large when the brazing material is melted to seal the exhaust hole, the molten brazing material is melted. There is a disadvantage that the material flows down from the exhaust hole. For this reason, the diameter of the exhaust hole is about 2.5 mm at the maximum, and as a result, the time required to exhaust the space between the inner bottle and the outer bottle tends to be longer.

Therefore, the present invention provides a vacuum structure which has good workability, can shorten the work time required for manufacturing, and can reliably seal the exhaust hole to ensure stable quality. It is an object to provide a method for sealing a body and a structure thereof.

[0007]

In order to solve the above-mentioned problems, a method for sealing a vacuum structure according to the present invention comprises the steps of: evacuation of a space formed by a constituent member from an exhaust hole formed in the constituent member; In the method for sealing a vacuum structure in which the exhaust hole is sealed by a sealing member, a brazing material disposing portion protruding outward from the space side is provided at an exhaust hole forming position of the component member, and After the brazing material is fixedly arranged, the sealing member is fixed by the brazing material so as to be located near the exhaust hole, and the brazing material is melted, so that the sealing member is placed in the brazing material arrangement. It is moved onto a brazing material disposed in the section, and the exhaust hole is sealed by the sealing member.

According to the method for sealing the vacuum structure, the sealing member for sealing the exhaust hole and the brazing material are arranged on the space side formed by the constituent members. A brazing material arranging portion is provided at the formation position, and the brazing material is irremovably attached to the brazing material arranging portion, and the sealing member is fixed to the brazing material. There is no displacement. As a result, it is not necessary to relatively carefully handle the components before evacuation, so that workability can be improved.

In the method for sealing a vacuum structure, it is preferable that the sealing member is fixed with a brazing material disposed in the brazing material disposing portion. Alternatively, the sealing member may be fixed by a brazing material different from the brazing material arranged in the brazing material disposing portion.

[0010] It is preferable that the brazing material is melted and fixed by heating the sealing member and disposing it on the brazing material. With this configuration, the sealing member can be easily fixed near the exhaust hole.

Further, it is preferable that the sealing member is formed in a spherical shape so that when the brazing material is melted, it rolls on the exhaust hole. In this case, it is more preferable to move the spherical sealing member by inclining or curving the bottom surface of the brazing material disposing portion of the component so that the exhaust hole is located at the lower end position. Alternatively, the sealing member is formed in a plate shape, and the plate-shaped sealing member is fixed with the brazing material so as to extend obliquely on the exhaust hole, and when the brazing material is melted, it falls over the exhaust hole and moves. It may be. In this case, since the sealing material is reliably moved onto the exhaust hole by melting the brazing material, stable quality can be ensured.

Preferably, the exhaust hole is formed in a shape in which the molten brazing material flows down. Further, it is preferable that a plurality of the exhaust holes are provided in the brazing material disposing portion of the constituent member. With such a configuration, it is possible to reduce the time required to exhaust the space formed by the constituent members.

Further, it is preferable that after the brazing material is arranged in the brazing material disposing portion, the exhaust hole is formed so as to penetrate the bottom surface of the brazing material disposing portion together with the brazing material.
With this configuration, it is possible to further suppress the movement or detachment of the brazing material in the brazing material disposing portion.

Further, it is preferable that a peripheral wall protruding outward is provided at a peripheral edge of the exhaust hole, so that the molten brazing material is prevented from flowing down. It is preferable that a cap for preventing the molten brazing material from flowing down is provided outside the brazing material disposing portion of the constituent member. With this configuration, it is possible to reliably prevent the inconvenience of the molten brazing material flowing down from the exhaust hole into the device for exhausting the space formed by the constituent members.

It is preferable to dispose the brazing material after applying the flux in the brazing material disposing portion. In this case, after applying the flux, it is more preferable to dispose a brazing material in the brazing material disposing portion, and then remove excess flux exposed from the brazing material. Alternatively, the brazing material may be disposed after the metal plating having good wettability such as Sn, Pb, Sn.Pb alloy, Sn.Ag alloy, Zn or Ni is applied in the brazing material disposing portion.
With such a configuration, the brazing material can be more reliably disposed without separating from the brazing material disposing portion.

Preferably, the sealing member is formed of a ferromagnetic metal material, and the brazing material is melted by induction heating the sealing member. Further, a constituent member provided with the brazing material disposing portion may be formed of a magnetic metal material, and the brazing material may be melted by induction heating the constituent member.

The vacuum structure is a vacuum double container comprising an inner bottle and an outer bottle, wherein the exhaust hole is formed in a bottom plate of the outer bottle, and the bottom plate of the outer bottle is disposed below to form the inner bottle. It is preferable to evacuate the space between and the outer bottle.

Further, in the sealing structure of the vacuum structure manufactured by the sealing method, the space formed by the constituent member is evacuated from the exhaust hole formed in the constituent member, and then the exhaust hole is sealed. In the sealing structure of a vacuum structure sealed by a brazing material, an arrangement portion for a brazing material protruding outward from the space side is provided at an exhaust hole forming position of the constituent member, and the brazing material is arranged in the brazing material arrangement portion. The exhaust hole is sealed by the sealing member by fixing the sealing member on the brazing material.

The sealing member may have a spherical shape.
In this case, the bottom surface of the brazing material disposing portion of the component is inclined or curved such that the exhaust hole is located at the lower end position. Alternatively, the sealing member has a plate shape.

Preferably, the exhaust hole is formed in a shape in which the molten brazing material flows down. A plurality of the exhaust holes may be provided in the brazing material disposing portion of the constituent member.

Further, a peripheral wall protruding outward may be provided on a peripheral edge of the exhaust hole. Furthermore, it is preferable that a cap for preventing the molten brazing material from flowing down is provided outside the brazing material disposing portion of the constituent member. In this case, it is more preferable that the cap has a mesh shape.

The sealing member can be made of a metal material having ferromagnetism. Further, the sealing member may be provided with metal plating such as Sn, Pb, Zn, Ni, or Cu on the surface of the metal material. Further, the brazing material is Sn, Pb
Or Sn-Pb based alloys, or Ag, B
Alloy containing i, Sb or In, or melting point of 20
It can be composed of glass at 0 ° C. to 450 ° C.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a thermos 1 which is a vacuum structure manufactured by the sealing method according to the first embodiment of the present invention. The thermos bottle 1 is a vacuum double container including an inner bottle 2 and an outer bottle 3 made of metal such as stainless steel. The inner bottle 2
And the outer bottle 3 are joined to each other by welding or the like at the mouth, and a space S is formed between them.

The outer bottle 3 is provided at the center of the bottom plate 4 with a brazing material disposing portion 5 projecting outward from the space S side. The brazing material disposing portion 5 has a bottom surface 5a that is inclined downward toward the center thereof, and an exhaust hole 6 is formed at the lowermost portion. A peripheral wall 5b that projects in an annular shape protrudes from the lower peripheral edge of the exhaust hole 6.

The exhaust hole 6 has a relatively large diameter so that the molten brazing material can flow down.
5 mm or more, about 1 m compared to the exhaust hole of a conventional thermos
m or more (140% or more) is also set to a large diameter. The exhaust hole 6 is sealed by fixing the sealing member 7A on the brazing material 8 melted and fixed in the brazing material disposing portion 5. The shape of the exhaust hole 6 is not limited to a circle.

The sealing member 7A is made of ferromagnetic iron,
It is formed in a spherical shape by metal materials such as nickel, cobalt, and alloys thereof. The brazing material 8
Sn, Pb or Sn-Pb based alloy, or an alloy obtained by adding Ag, Bi, Sb or In to them, or
Glass having a melting point of 200 ° C. to 450 ° C. is exemplified.

Next, a method of sealing the thermos bottle 1 will be described. First, before assembling the double container 1 'shown in FIG. 2, as shown in FIG. 3 (A), the flux 9 is applied to the inner surface of the brazing material disposing portion 5 of the bottom plate 4 by coating or the like. Instead of adhering the flux 9, Sn, Pb, SnPb alloy, Sn
Metal plating such as Ag alloy, Zn or Ni may be applied.

Next, as shown in FIG. 3B, the brazing material 8 is melted in the brazing material disposing portion 5 of the bottom plate 4, and the brazing material disposing portion 5 around the exhaust hole 6 is substantially formed by the brazing material 8. Arrange to be satisfied. The exhaust holes 8 formed in the brazing material 8
a is formed by using a rod-shaped jig (not shown) having poor wettability or an annular solid brazing material so that the exhaust hole 6 of the bottom plate 4 is formed.
It is formed to be slightly smaller. As described above, by pre-melting and fixing the brazing material 8 to the brazing material disposing portion 5, most of the occluded gas contained in the brazing material 8 can be removed. Further, since the flux is applied in the brazing material disposing portion 5 in the previous step, the brazing material 8 disposed can be securely attached so as not to be separated from the brazing material disposing portion 5.

Thereafter, the flux 9 exposed on the surface of the brazing material 8 is washed away, etc.
As shown in (C), the flux 9 is removed. Thereby, when the space S is evacuated in a later step, it is possible to prevent the flux 9 from evaporating and lowering the degree of vacuum in the space S. In the case where the metal plating is applied instead of the flux 9, this cleaning step is unnecessary.

Next, the sealing member 7A is heated, and FIG.
As shown in (D), it is arranged on the brazing material 8 near the exhaust holes 6, 8a. As a result, the brazing material 8 disposed in the brazing material disposing portion 5 is melted, and the sealing member 7A is temporarily fixed to the disposing position.

As shown in FIG. 3E, the brazing material arranging portion 5 is so covered as to cover the exposed surface of the sealing member 7A.
The same brazing material 8 as the brazing material 8 disposed on the sealing member 7A may be applied to improve the wettability of the entire surface of the sealing member 7A.

As described above, in the sealing method, since the brazing material disposing portion 5 for disposing the brazing material 8 is provided on the bottom plate 4 of the outer bottle 3, the brazing material 8 is easily disposed. In addition to this, it is possible to prevent the brazing material 8 once disposed from being displaced. The sealing member 7A
By heating and disposing, the brazing material 8 is partially melted, and the sealing member 7A can be disposed simply and reliably. Further, if the exposed surface of the sealing member 7A is covered with the brazing material 8, the sealing member 7A will be formed in a later step.
Can be reliably prevented from coming off.

Next, the components 2, 3, and 4 are assembled to form a double container 1 '. That is, the inner bottle 2 is inserted from the opened bottom of the outer bottle 3 and the mouths of the inner bottle 2 and the outer bottle 3 are fixed to each other by welding or the like. The bottom plate 4 is arranged and similarly fixed by welding or the like.

Next, the double container 1 'is placed in a well-known heating furnace or the like, and as shown in FIG. The space S between the inner bottle 2 and the outer bottle 3 is evacuated while removing the gas absorbed in the metal forming the inner bottle 2 and the outer bottle 3. In addition, you may exhaust by a vacuum heating furnace.

Specifically, first, the mouth of the double container 1 ′ is turned upright, and the exhaust jig 11 of the exhaust device 10 is connected to the exhaust hole 6 of the outer bottle 3. Place to cover. Thereby, the bottom plate 4 of the outer bottle 3 is kept airtight by the seal member 12 attached to the exhaust port 11a.

The inner bottle 2 is heated by a heating means (not shown).
The space S between the inner bottle 2 and the outer bottle 3 is exhausted through the exhaust holes 6 and 8a while heating the surface of the outer bottle 3 at a predetermined temperature at which the brazing material 8 does not melt. Thereby, the inner bottle 2
The inside of the space S is exhausted from the exhaust holes 6, 8a while removing attached substances such as oil and moisture and the stored gas attached to the outer bottle 3. At this time, since the diameter of the exhaust hole 6 is larger than that of the conventional exhaust hole by 1 mm or more, the exhaust can be efficiently exhausted. The oil,
Moisture and occluded gas are stored in the double container 1 ′
It may be preheated and removed in advance before being placed at zero or before assembling the double container 1 '.

Then, when the space S of the double vessel 1 ′ reaches a predetermined degree of vacuum by the evacuation operation, the control device 15 supplies the induction heating coil 14 wound around the ferrite core 13 via the inductance adjusting coil 16 to the induction heating coil 14. 20 ~
A high frequency current of 50 kHz is applied. As a result, the electromagnetic wave from the induction heating coil 14 passes through the exhaust jig 11, and the sealing member 7A having ferromagnetism is heated by the electromagnetic induction action, and the brazing material 8 located on the outer peripheral portion of the sealing member 7A. Melts.

As a result, the spherical sealing member 7A is released from the temporarily fixed state, and rolls on the exhaust hole 6 by its own weight while melting the surrounding brazing material. Then, due to the heat of the sealing member 7A, all the brazing materials 8 in the brazing material disposing portion 5 are melted and sufficiently spread and adhere to the outer peripheral portion of the sealing member 7A.

As a result, as shown in FIG. 1, the sealing member 7A is air-tightly fixed on the brazing material 8 disposed in the brazing material disposing portion 5, whereby the exhaust hole 6 is sealed by the sealing member 7A. Sealing can be performed reliably.

As described above, according to the first embodiment,
Since the brazing material 8 is disposed in the brazing material disposing portion 5 of the bottom plate 4 and the sealing member 7A is temporarily fixed to the brazing material 8, they are detached during the assembly process of the double container 1 '. I will not do it. Further, since the sealing member 7A is configured to roll on the exhaust hole 6 along the inclination of the bottom surface 5a of the brazing material disposing portion 5, the sealing member 7A
Can be reliably sealed. Further, by arranging the heated sealing member 7A on the brazing material 8, the sealing member 7A can be temporarily and easily temporarily fixed, so that workability is good.

In the first embodiment, the peripheral wall 5b may not be provided on the peripheral edge of the exhaust hole 6. After the brazing material 8 is melted and fixed in the brazing material disposing portion 5 to a substantially full amount, the exhaust holes 6 and 8a may be formed by a drill or the like. As shown in FIG. 3 (E), a brazing material is adhered to the exposed outer peripheral portion of the sealing member 7A. However, in order to improve the wettability on the surface of the sealing member 7A, Sn is used. , Pb, Sn-Pb alloy, Sn-Ag alloy, Z
When a metal plating of n, Ni, Cu, or the like is performed, the step of covering the surface of the sealing member 7A with the brazing material 8 is not always necessary, and can be performed up to the step shown in FIG. .

FIG. 4 shows a thermos bottle 1 manufactured by the sealing method of the second embodiment. The thermos bottle 1 is different in that a plate-shaped sealing member 7B is used instead of the spherical sealing member 7A shown in the first embodiment. Further, in the present embodiment, the bottom surface 5a of the brazing material disposing portion 5 of the bottom plate 4 is formed horizontally without being inclined, and the peripheral wall 5b is not formed.

Next, a method of sealing the thermos bottle 1 will be described. First, as in the first embodiment, before assembling the double container, as shown in FIG.
The flux 9 is applied to the inner surface of the brazing material disposing portion 5 by applying the flux 9 or the like. In this case, in the method of the second embodiment, the exhaust hole 6 is not formed in the bottom surface 5a of the brazing material disposing portion 5 in this state. Further, similarly to the first embodiment, metal plating having good wettability may be applied instead of attaching the flux 9.

Next, as shown in FIG. 5B, the brazing material 8 is melted in the brazing material disposing portion 5 of the bottom plate 4,
The brazing material disposing portion 5 is disposed so as to be substantially filled with the brazing material 8.

Thereafter, as shown in FIG. 5 (C), the excess flux 9 exposed on the surface of the brazing material 8 is washed away to remove excess flux 9.

Next, as shown in FIG. 5 (D), the center of the brazing material disposing portion 5 of the bottom plate 4 is made to penetrate with the brazing material 8 using a drill or the like, so that the exhaust holes 6 and 8a are formed. Form. By forming the exhaust holes 6 and 8a after disposing the brazing material 8 in this way, it is possible to prevent the brazing material 8 from being displaced or separated in a later production process. Either the step of forming the exhaust holes 6 and 8a or the step of removing the flux 9 may be performed first.

Thereafter, as shown in FIG. 5E, the sealing member 7B is heated, and the sealing member 7B is
Is inserted into the brazing material 8 near the exhaust holes 6, 8a so as to be inclined upward. Thereby, similarly to the first embodiment, the brazing material 8 arranged in the brazing material disposing portion 5 is melted, and the sealing member 7B is temporarily fixed to the disposing portion while maintaining the inclined state. .

Next, as in the first embodiment, after assembling the double container, it is placed in the exhaust device 10 and the inner bottle 2 is placed.
The space S between the inner bottle 3 and the outer bottle 3 is exhausted, and the exhaust hole 6 is sealed.

When the exhaust hole 6 is sealed, the plate-shaped sealing member 7B is induction-heated by induction heating in the same manner as described above, so that the brazing material 8 at the fixed portion of the sealing member 7B is first melted. I do. Thereby, the sealing member 7B disposed so as to be inclined is released from the temporarily fixed state,
It falls on the brazing material 8 and moves. And the sealing member 7B
By the heat, the brazing material 8 in the brazing material disposing portion 5 is melted and spread sufficiently on the outer peripheral portion of the sealing member 7B so that the flat sealing member 7B is air-tight on the brazing material 8. , And the exhaust hole 6 is securely sealed by the sealing member 7A.

In the second embodiment, the exhaust holes 6 may be provided in advance as in the first embodiment. Further, an annular peripheral wall similar to that of the first embodiment may be protruded from the peripheral edge of the exhaust hole 6 of the brazing material disposing portion 5 having the horizontal bottom surface 5a. Further, the plate-shaped sealing member 7B may be made thick to increase the weight. In this case, the time required for sealing can be reduced.

FIGS. 6A and 6B show a thermos bottle 1 manufactured by the sealing method of the third embodiment. This thermos 1
Is different from the second embodiment only in that a plurality of exhaust holes 6 'are formed in a bottom surface 5a of a brazing material disposing portion 5 formed in a bottom plate 4 of the outer bottle. These exhaust holes 6 '
May be formed before disposing the brazing material 8 in the brazing material disposing portion 5 as in the first embodiment.
As in the embodiment, it may be formed after the brazing material 8 is provided. In this way, the total opening area of the exhaust holes 6 'is increased, and the exhaust efficiency of the space S can be improved. Further, these exhaust holes 6 'are securely sealed by the sealing member 7B.

FIGS. 7A and 7B show a thermos bottle 1 manufactured by the sealing method of the fourth embodiment. The thermos 1
A mesh-shaped cap 20 is provided outside the brazing material arranging portion 5.
The second embodiment differs from the second embodiment only in that the second embodiment is attached. The gap between the bottom surface 20a of the cap 20 and the bottom surface 5a of the brazing material disposing portion 5 is set so as not to be too large. Specifically, the exhaust holes 6
When the diameter of the bottom surface 20a is set to about 4 mm,
The gap with “a” is set to be about 1 mm.

In the sealing method of the fourth embodiment, even when the exhaust hole 6 having a large diameter is formed, the molten brazing material 8 ′ flows down from the exhaust hole 6 when the exhaust hole 6 is sealed. This can be reliably prevented. As a result, it is possible to reliably prevent inconvenience caused by the adhesion of the molten brazing material to the exhaust device. When the cap 20 of the fourth embodiment is applied to any one of the thermos bottles 1 described in the first, second and third embodiments, the same operation and effect can be obtained.

The sealing method and the sealing structure of the vacuum structure of the present invention are not limited to the above-described structure. For example, in each of the above embodiments, the sealing members 7A and 7B are fixed to the brazing material 8 disposed in the brazing material disposing portion 5, but as shown in FIGS. 8A and 8B, Brazing material placement part 5
May be fixed by another brazing material 21 other than the brazing material 8 arranged in the first embodiment. As shown in FIG. 9, a plate-shaped sealing member 7C having a shape slightly smaller than the inner circumference of the brazing material disposing portion 5 is provided.
The sealing member 7C is arranged on the upper edge of the brazing material disposing portion 5, and the outer peripheral portion of the sealing member 7C and the inner peripheral portion of the brazing material disposing portion 5 are joined by a brazing material 21 at a predetermined interval. You may do so.

Further, the sealing members 7A, 7B and 7C are not formed of a ferromagnetic metal material but formed of a metal material such as stainless steel or steel, and Sn is formed on the surface of the metal material in order to improve wettability. , Pb, Zn, Ni, Cu or the like. In this case, the bottom plate 4 forming the brazing material disposing portion 5 is formed of a magnetic metal material,
It is preferable to melt the brazing material 8 from the bottom plate 4 side. Also in this configuration, the brazing material 8,
When 21 melts, the sealing members 7A, 7B, 7C move onto the exhaust holes 6, 8a, as in the first embodiment, and the exhaust holes 6 can be reliably sealed by the sealing members.

Further, the places where the brazing material disposing portion 5 and the exhaust holes 6 are formed are not limited to the bottom plate 4 but may be formed on the body of the outer bottle 3 or the like. Further, the vacuum structure to which the sealing method and the sealing structure are applied can obtain the same operation and effect when applied to any of a vacuum double tube, a vacuum heat insulating panel, a vacuum vessel and the like.

[0057]

As is apparent from the above description, according to the method for sealing a vacuum structure of the present invention and the structure thereof, the brazing material is arranged in the brazing material arranging portion formed on the constituent member.
Since the sealing member is fixed with the brazing material so as to be located near the exhaust hole so as not to be separated from the constituent members, workability such as handling can be improved. Further, when the brazing material is melted when the exhaust hole is sealed, the sealing member moves on the brazing material, and the sealing member is hermetically melted and fixed to the brazing material. In addition, since the sealing member is sealed and the wetting property of the surface of the sealing member is improved, high reliability and stable quality can be secured. Further, since the exhaust hole is sealed by a sealing member, and the diameter of the exhaust hole formed in the constituent member can be made larger than that of the related art, the space formed by the constituent member is reduced. The time required for exhaust can be reduced.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a thermos as a vacuum structure manufactured by a sealing method according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which the double container is sealed.

FIGS. 3A, 3B, 3C, 3D, and 3E are cross-sectional views showing a process of disposing a brazing material and a sealing member in a brazing material disposing portion of a bottom plate according to the first embodiment; FIG.

FIG. 4 is a partial cross-sectional view illustrating a thermos as a vacuum structure manufactured by the sealing method according to the second embodiment.

FIGS. 5A, 5B, 5C, 5D, and 5E are cross-sectional views showing a process of disposing a brazing material and a sealing member in a brazing material disposing portion of a bottom plate according to a second embodiment; FIG.

FIGS. 6A and 6B are partial cross-sectional views showing a thermos as a vacuum structure manufactured by a sealing method according to a third embodiment.

FIGS. 7A and 7B are partial cross-sectional views illustrating a thermos as a vacuum structure manufactured by a sealing method according to a fourth embodiment.

FIGS. 8A and 8B are partial cross-sectional views showing a modification of the sealing method.

FIG. 9 is a partial sectional view showing another modification of the sealing method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Thermos (vacuum structure), 1 '... Double container, 2 ... Inner bottle, 3 ... Outer bottle, 4 ... Bottom plate, 5 ... Brazing material arrangement part, 5a ... Bottom surface, 6 ... Exhaust hole, 7A, 7B, 7C: sealing member, 8: brazing material.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shinya Yasuda 1-20-5 Tenma, Kita-ku, Osaka-shi, Osaka

Claims (30)

[Claims] 1. A method for sealing a vacuum structure in which a space formed by a constituent member is evacuated from an exhaust hole formed in the constituent member, and the exhaust hole is sealed by a sealing member. A brazing material disposing portion projecting outward from the space side is provided at the exhaust hole forming position, and after the brazing material is fixedly disposed in the brazing material disposing portion, the sealing member is positioned near the exhaust hole. By fixing the stop member with a brazing material and melting the brazing material, the sealing member is moved onto the brazing material arranged in the brazing material disposing portion,
A method for sealing a vacuum structure, comprising sealing the exhaust hole with the sealing member. 2. The method for sealing a vacuum structure according to claim 1, wherein the sealing member is fixed by a brazing material disposed in the brazing material disposing portion. 3. The method for sealing a vacuum structure according to claim 1, wherein the sealing member is fixed by a brazing material different from the brazing material arranged in the brazing material disposing portion. 4. The heating device according to claim 1, wherein the sealing member is heated and arranged on the brazing material to melt and fix the brazing material. Method for sealing a vacuum structure. 5. The vacuum according to claim 1, wherein the sealing member is spherical, and when the brazing material is melted, the sealing member rolls on an exhaust hole. How to seal the structure. 6. A bottom surface of a brazing material disposing portion of the component member,
The method for sealing a vacuum structure according to claim 5, wherein the spherical sealing member is moved while being inclined or curved so that the exhaust hole is located at a lower end position. 7. The sealing member is formed in a plate shape, and the plate-shaped sealing member is fixed with the brazing material so as to extend obliquely on the exhaust hole, and when the brazing material is melted, it falls on the exhaust hole. The method according to claim 1, wherein the vacuum structure is moved. 8. The method for sealing a vacuum structure according to claim 1, wherein the exhaust hole is formed in a shape in which a molten brazing material flows down. 9. The apparatus according to claim 1, wherein a plurality of said exhaust holes are provided in a brazing material disposing portion of said constituent member.
The sealing structure for a vacuum structure according to any one of the above. 10. The exhaust hole is formed by arranging a brazing material in the brazing material disposing portion and then penetrating the bottom surface of the brazing material disposing portion together with the brazing material. A method for sealing a vacuum structure according to claim 9. 11. The vacuum structure according to claim 1, wherein a peripheral wall protruding outward is provided at a peripheral edge of the exhaust hole to suppress the flow-down of the molten brazing material. Sealing method. 12. The cap according to claim 1, wherein a cap for preventing the molten brazing material from flowing down is provided outside the brazing material disposing portion of the constituent member. A method for sealing a vacuum structure. 13. The method for sealing a vacuum structure according to claim 1, wherein the brazing material is provided after a flux is applied to the brazing material disposing portion. . 14. The method according to claim 13, wherein after the flux is applied, a brazing material is disposed in the brazing material disposing portion, and then the excess flux exposed from the brazing material is removed. Method for sealing a vacuum structure. 15. Sn, Pb, S in the brazing material disposing portion
13. The brazing material according to any one of claims 1 to 12, wherein the brazing material is provided after performing metal plating with good wettability, such as n-Pb alloy, Sn-Ag alloy, Zn or Ni. A method for sealing a vacuum structure according to the above. 16. The method according to claim 1, wherein the sealing member is formed of a ferromagnetic metal material, and the brazing material is melted by induction heating the sealing member.
The method for sealing a vacuum structure according to any one of the above. 17. The component according to claim 1, wherein a component for providing the brazing material disposing portion is formed of a magnetic metal material, and the component is melted by induction heating. The method for sealing a vacuum structure according to claim 1. 18. The vacuum structure is a vacuum double container comprising an inner bottle and an outer bottle, wherein the exhaust hole is formed in a bottom plate of the outer bottle, and the bottom plate of the outer bottle is disposed below the vacuum bottle. The method for sealing a vacuum structure according to any one of claims 1 to 17, wherein a space between the inner bottle and the outer bottle is evacuated. 19. A sealing structure for a vacuum structure, wherein a space formed by a constituent member is evacuated from an exhaust hole formed in the constituent member, and the exhaust hole is sealed by a sealing member. With an arrangement portion for brazing material projecting outward from the space side at the exhaust hole forming position,
Sealing a vacuum structure, wherein a brazing material is disposed in the brazing material disposing portion, and the exhaust hole is sealed by the sealing member by fixing the sealing member on the brazing material. Construction. 20. The sealing structure according to claim 19, wherein the sealing member has a spherical shape. 21. The sealing structure for a vacuum structure according to claim 20, wherein the bottom surface of the brazing material disposing portion of the constituent member is inclined or curved so that the exhaust hole is located at a lower end position. . 22. The sealing structure according to claim 19, wherein the sealing member has a plate shape. 23. The sealing structure for a vacuum structure according to claim 19, wherein the exhaust hole is formed in a shape in which a molten brazing material flows down. 24. The sealing structure for a vacuum structure according to claim 19, wherein a plurality of said exhaust holes are provided in a brazing material disposing portion of said constituent member. 25. A peripheral wall protruding outward at a peripheral edge of said exhaust hole.
The sealing structure for a vacuum structure according to any one of the above. 26. The cap according to claim 19, wherein a cap for preventing the molten brazing material from flowing down is provided outside the brazing material disposing portion of the constituent member. Sealing structure of the vacuum structure. 27. The sealing structure according to claim 26, wherein the cap has a mesh shape. 28. The device according to claim 19, wherein the sealing member is made of a metal material having ferromagnetism.
The sealing structure for a vacuum structure according to any one of the above. 29. The sealing member has a surface on a metal material.
The sealing structure for a vacuum structure according to any one of claims 19 to 28, wherein a metal plating such as n, Pb, Zn, Ni, or Cu is applied. 30. The brazing material is Sn, Pb or Sn.
-A Pb-based alloy, or an alloy obtained by adding Ag, Bi, Sb, or In thereto, or a melting point of 200 ° C.
The sealing structure for a vacuum structure according to any one of claims 19 to 29, wherein the sealing structure is made of glass at 50 ° C.