JP3148080B2 - Manufacturing method of vacuum insulation products - 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 of manufacturing a vacuum insulation product, and more particularly, to a method of manufacturing a vacuum insulation product, comprising a double wall having an outer wall and an inner wall, wherein the inner wall has a high temperature side and the outer wall has a low temperature side. The present invention relates to an improvement in a method of manufacturing a vacuum heat-insulated product in which a double wall is inserted and the inside of a double wall is evacuated.

[0002]

2. Description of the Related Art Conventionally, as a generally known industrial insulation product for a heating furnace or a cool box, as a super insulation, a lamination is made by alternately laminating a large number of metal foils having small radiant heat and thin inorganic fiber sheets. Put your body on the hot side,
Further, there is known a vacuum insulation product in which a heat insulation material formed by laminating boards made of inorganic fibers on a low temperature side is filled in a vacuum insulation body, and after sealing, the inside is evacuated to exhibit a high insulation effect. (e.g. Japanese Patent Application No. flat 5-124901, drawing or the 6-99310 Pat drawings and the like). As a method of manufacturing these heat-insulating products, a heat-insulating material consisting of a board made of an inorganic fiber and an alternate laminate of metal foil and an inorganic fiber sheet is arranged on the inner surface of an outer container constituting an outer wall of the vacuum heat-insulating product, and inside thereof. inner container insertion methods are hermetically welded to the opening of the insert the inner container outer container and the inner container which constitutes the inner wall of the vacuum insulation products and (Japanese Patent Application No. flat 5-124901, drawing) on an outer surface of the inner container after disposing the filler covered with the outer container open part of the peripheral wall, compaction filling method of welding the opening compacted hermetically by applying pressure from the outside (Japanese Patent Application flat 4-294677 No. Document drawings) are known.

[0003]

2. Description of the Related Art In the case where the inside of a heat-insulating product is at a high temperature, for example, the heat-insulating material is formed by alternately laminating a large number of metal foils having small radiant heat and thin inorganic fiber sheets on the inner wall side in order to cut off heat radiation. However, in the case of the above inner container insertion method, there is a disadvantage that the thin metal foil or the inorganic fiber sheet is damaged by friction or the like when the inner container is inserted.

In order to prevent this, it is necessary to harden the laminate into a board shape using a resin binder or the like.
Since the binder deteriorates the degree of vacuum, it has to be completely removed before evacuation of the inside of the heat insulating wall, and there has been a drawback that a heat treatment or the like is required to increase the number of steps.

[0005] In the consolidation filling method, after filling a heat insulating material, the outer container is subjected to a pressure free of a vacuum leak in a state where a pressure necessary for consolidating the filling material is applied and the heat insulating material is present on the back surface of the welded portion. Has to be performed, and there is a disadvantage that the construction is very troublesome.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and it is possible to insert a laminate of a metal foil and an inorganic fiber sheet without breaking it without forming a board. Another object of the present invention is to provide a method for easily manufacturing a vacuum heat-insulated product by preventing stress from being applied to a weld portion and preventing heat insulating material from contacting when performing welding that can withstand a vacuum leak.

[0007]

That is, the method for producing a vacuum insulated product according to the present invention comprises a double wall 1 comprising an outer wall 1A and an inner wall 1B.
A method for manufacturing a vacuum heat-insulated product 1 in which a heat insulating material 2 is inserted into a double wall 1C, and the inside of the double wall 1C is evacuated, the inner wall 1B being on the high temperature side and the outer wall 1A being on the low temperature side.
The inner container 3 serving as the inner wall 1B is covered and supported on a support jig 4 which is in contact with the inner surface of the inner container 3 without any gap, and the outer surface of the inner container 3 is coated with an inorganic fiber sheet 5A and a metal foil 5B having a low heat radiation rate. A heat insulating material 2 composed of a laminate of a laminate 5C and an inorganic fiber board 6 alternately laminated is arranged, and then the inner diameter is made smaller than the thickness of the heat insulating material 2, and the compression ratio when fitted is large against vacuum. An outer container 7 serving as the outer wall 1A having an inner diameter such that the compression ratio is substantially equal to the atmospheric pressure is forcibly fitted to the inner container 3 while the heat insulating material 2 is being compressed, and the outer container 7 is externally fitted to the inner container 3 in a completely fitted state. The opening edges 3A and 7A of the container 7 are hermetically welded.

[0008]

The vacuum insulation product 1 according to the method of the present invention comprises a double wall 1C having an outer wall 1A and an inner wall 1B, as shown in FIG. 1, wherein the inner wall 1B has a high temperature side and the outer wall 1A has a low temperature side. It is assumed that a vacuum heat insulating product 1 is formed by inserting a heat insulating material 2 into a wall 1C and evacuating the inside.

In such a vacuum heat insulating product, a heat insulating material 2 composed of a laminated body 5C composed of an alternate laminated body of an inorganic fiber sheet 5A and a metal foil 5B having a low heat radiation rate on the inner wall 1B side and an inorganic fiber board 6 is provided. Need to be placed. Therefore, in order to prevent the laminate 5C from being damaged, in the present invention, the inner container 3 serving as the inner wall is first supported from the inner surface by the support jig 4, and the outer surface thereof is formed of the inorganic fiber sheet 5A and the metal foil 5B having a small heat radiation rate. Are laminated alternately, and an inorganic fiber board 6 is disposed outside of the laminate 5C.
And an outer container 7 serving as an outer wall is covered using the inorganic fiber board 6 outside the heat insulating material 2 as a cushion material. Therefore, even if the outer container 7 is slightly forcibly covered, the laminated body 5C inside the heat insulating material 2 is protected by the inorganic fiber board 6 on the outside thereof and does not break.

The inner diameter of the outer container 7 is smaller than the thickness of the heat insulating material 2, and the inner diameter of the outer container 7 is such that the compression ratio when fitted is substantially equal to the atmospheric pressure with respect to vacuum. Therefore, a predetermined pressure density of the heat insulating material 2 is obtained by the forced fitting, and the density is already set to a value that can withstand the atmospheric pressure with respect to the vacuum at the time of the fitting. Further, at the time of this fitting, the friction at the time of insertion is exclusively applied to only the inorganic fiber board 6, so that the inorganic fiber sheet 5A and the metal foil 5B laminated on the inside are not damaged.

Since the inner surface of the inner container 3 is supported by the support jig 4, it does not deform even if the outer container 7 serving as the outer wall 1A is forcibly fitted. Then, the outer container 7 and the opening of the inner container 3 are hermetically welded after the outer fitting. At this time, since the welded portion becomes an open end face of the inner container 3 and the outer container 7, the influence of stress is small and there is almost no contact with the heat insulating material 2, so that highly reliable welding against vacuum leak can be performed.

[0012]

Next, an embodiment of the present invention will be described. In the following examples, the outer dimensions are width 1000 mm, depth 600 mm, height 1700 m
m, a vacuum insulated container having a thickness of 37 mm and a high temperature on the inner surface side of the vacuum insulated wall 1C was manufactured.

Embodiment 1 First, as shown in FIG. 2, as an inner container 3 serving as an inner wall 1B, an upper opening type integrally formed container made of a stainless steel plate having a thickness of 1 mm is formed. 922m wide (= 1000mm-37mm ×
2-1 mm x 4 (thickness of container), height 1662 mm (= 1700 mm-37
mm-1mm (same as above), depth 522mm (= 600mm -37mm × 2 -1mm
The inner container 3 was fixed on the supporting jig 4 of × 4). Next, as shown in FIG. 3, a heat insulating material having a total thickness of 44 mm, comprising a laminate 5C in which inorganic fiber sheets 5A and metal foils 5B having a low thermal emissivity are alternately laminated on the outer surface of the inner container 3, and an inorganic fiber board 6 2 were laminated.

An outer container 7 which is also an upper opening type integrally formed container and has an outer wall 1A having an outer width of 1,000 mm, a depth of 600 mm and a height of 1700 mm is compressed while the heat insulating material 2 is compressed as shown in FIG. It was forcibly fitted. In addition, the thing which provided the curve 7B which curves smoothly outside so that the inorganic fiber board 6 was not hooked in the opening part of the outer container 7 was used. In the drawing, reference numeral 9 denotes a jig for pressing the outer container 7.

Then, as shown in FIG. 5, the inner container 3 serving as the inner wall and the opening edges 3A and 7A of the outer container 7 serving as the outer wall were hermetically welded in a completely fitted state. At this time, the welding portion between the opening edges 3A and 7A was a flange-like portion 7C outside the container 1 as shown in the figure, and was set to a position where the heat of welding was not directly applied to the internal heat insulating material.

[Embodiment 2] Outer container 7 in Embodiment 1
As shown in FIG. 6, a vacuum insulated product was manufactured in the same manner except that a linear cut end was used, and a sliding plate 8 made of a silicone resin sheet was interposed at the open end.

Comparative Example 1 A vacuum insulated container having the same size as that of Example 1 was manufactured by a conventional inner container insertion method. That is,
On the inner surface of the outer container that constitutes the outer wall, a layer of metal fibers and inorganic fiber sheets and a layer made of inorganic fibers are fixed with a binder and a heat insulating material serving as a board is arranged and fixed. Was inserted and the outer container and the opening of the inner container were hermetically welded to produce a vacuum insulated container.

Comparative Example 2 A vacuum insulated container having the same dimensions as in Example 1 was manufactured by a conventional consolidation method. That is, after disposing the filler on the outer surface of the inner container, cover the outer container with a part of the peripheral wall opened, apply surface pressure from the outer surface of the outer container to consolidate the filler, and further hermetically seal the opening. To produce a vacuum insulated container.

Next, the time required for filling the heat insulating material 2 and the presence or absence of dent deformation of the inner and outer walls due to the atmospheric pressure after vacuum processing were compared for Examples 1 and 2 and Comparative Examples 1 and 2. As for the time, the consolidation filling method of Comparative Example 2 required 3 hours, whereas in the case of Examples 1 and 2, only 1 hour was required, and a reduction of 2 hours was achieved. In the method of the present invention, the outer wall 1A,
Since the inner and outer containers 3 and 7 serving as the inner wall 1B are formed in advance, the time for manufacturing the container is reduced as compared with Comparative Example 2,
The time required for container fabrication was reduced by about 2 hours. In addition, in the case of the method of the present invention, the time required for evacuating the inside of the double wall was only 1/4 that of Comparative Example 1 because no binder was used. In addition, no dent deformation of the inner and outer walls after the vacuum treatment was observed in any of the examples and the comparative examples.

[0020]

As described above, the present invention does not require the heat insulating material composed of the laminated body to be solidified with the resin binder as compared with the method of manufacturing a vacuum heat insulating product by the inner container press-fitting method. It becomes unnecessary. further,
There is no need to remove the resin binder that adversely affects the vacuum, and the evacuation processing time is reduced to １ ／.

Further, compared with the compaction filling method, the time required to complete the filling of the heat insulating material is reduced to 1/3 since the outer container welding step is not required after the filling. In addition, the time for manufacturing the container excluding the filling operation is reduced by two hours. Furthermore, since the inner and outer vessels are welded without any heat insulating material on the back surface of the welded portion, reliable welding is possible, and various effects such as highly reliable welding without vacuum leak can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a heat-insulating product (container) as a premise of the present invention.

FIG. 2 is a cross-sectional view showing a state in which a container serving as an inner wall is supported.

FIG. 3 is a cross-sectional view showing a state where a heat insulating material is arranged on the outer surface of the container-like body serving as an inner wall.

FIG. 4 is a cross-sectional view showing a state in which a container serving as an outer wall is externally fitted.

FIG. 5 is a cross-sectional view showing a state where an opening of a container-like body constituting the inner and outer walls is welded.

FIG. 6 is an enlarged sectional view of a main part showing another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulated product 1A ... Outer wall 1B ... Inner wall 1C ... Double wall 2 ... Insulation material 3 ... Inner container 3A ... Opening edge of the container-like body used as an inner wall 4 ... Supporting jig 5A ... Inorganic fiber sheet 5B ... Heat radiation rate Small metal foil 5C Laminated body 6 Inorganic fiber sheet body 7 Outer container 7A Opening edge of outer container 7B Smoothly curved curve 7C Flange-shaped part 8 Slide plate

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16L 59/06

Claims (1)

(57) [Claims] 1. A heat insulating material 2 is inserted into a double wall 1C comprising an outer wall 1A and an inner wall 1B, wherein the inner wall 1B is on the high-temperature side and the outer wall 1A is on the low-temperature side. In the method for manufacturing the vacuum heat-insulated product 1 obtained by vacuuming, the inner wall 1B
The inner container 3 to be formed is covered and supported on a support jig 4 which is in contact with the inner surface of the inner container 3 without any gap, and the outer surface of the inner container 3 is alternately provided with an inorganic fiber sheet 5A and a metal foil 5B having a small heat radiation rate. A heat insulating material 2 composed of a laminate of a laminated laminate 5C and an inorganic fiber board 6 is arranged, and then has an inner diameter smaller than the thickness of the heat insulating material 2, and the compression ratio when fitted is reduced to the atmospheric pressure with respect to vacuum. The inner container 3 and the outer container 7 are forcibly fitted to the outer container 7 serving as the outer wall 1A having an inner diameter such that the compression ratio is substantially equal to each other while the heat insulating material 2 is compressed. Characterized in that the opening edges 3A and 7A are hermetically welded to each other.