JPH08121680A - Manufacture of vacuum insulated product - Google Patents

Abstract

PURPOSE: To enable insertion without damage, without forming a laminated body into a board by disposing heat insulating material, formed of a laminated body constituted of inorganic fiber and a laminated body with inorganic fiber sheets and metallic foil with a small heat radiation rate alternately laminated, on the outer surface of an inner container, and fitting an outer container forcibly while compressing the heat insulating material. CONSTITUTION: An inner container to be an inner wall is supported from the inner surface by a supporting jig, and a laminated body with inorganic fiber sheets 5A and metallic foil 5B with a low heat radiation rate alternately laminated is disposed on the outer surface. An inorganic fiber board 6 is further disposed on the outside to form heat insulating material 2. An outer container is then put on utilizing the outer inorganic fiber board 6 of the heat insulating material as cushioning material. Accordingly, even if putting this outer container rather forcibly, the inner laminated body 5C of the heat insulating material 2 is protected from damage by the outer inorganic fiber board 6.

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 heat insulating product, and more specifically, to a heat insulating material in a double wall having a double wall having an outer wall and an inner wall, the inner wall side being the high temperature side and the outer wall side being the low temperature side. The present invention relates to an improvement in a method for producing a vacuum heat insulating product by inserting a vacuum into the inside of a double wall.

[0002]

2. Description of the Related Art Conventionally, as generally known as super insulation as an industrial heat insulating product for heating furnaces and cold storages, a metal foil with small radiant heat and a thin inorganic fiber sheet are laminated alternately in large numbers. Put your body on the hot side
In addition, there is known a vacuum heat insulating product that exhibits a high heat insulating effect by filling a vacuum heat insulating material with a heat insulating material formed by laminating a board made of inorganic fibers on the low temperature side and then vacuum-exhausting the inside. (For example, Japanese Patent Application No. 5-124901, drawings, drawings of 6-99310, etc.). As a method for producing these heat insulating products, the inner surface of the outer container that constitutes the outer wall of the vacuum heat insulating product is arranged with a heat insulating material consisting of an alternating laminated body of metal foil and an inorganic fiber sheet and a board made of inorganic fibers, and inside thereof. Inner container insertion method of inserting the inner container that constitutes the inner wall of the vacuum insulation product and welding the outer container and the opening of the inner container in an airtight manner (Japanese Patent Application No. 5-12901, drawings) and the outer surface of the inner container. After arranging the filler, a compaction filling method of covering the outer container with a part of the peripheral wall opened, consolidating by applying pressure from the outside to hermetically weld the opening (Japanese Patent Application No. 4-294677). Document drawings) are known.

[0003]

[Problems of the Prior Art] For example, when the inside of a heat insulating product has a high temperature, the heat insulating material has a large number of metal foils having small radiant heat and thin inorganic fiber sheets alternately laminated on the inner wall side in order to block heat radiation. However, in the case of the above-mentioned inner container insertion method, there is a drawback that the thin metal foil or the inorganic fiber sheet is damaged due to friction when inserting the inner container.

In order to prevent this, it is necessary to firmly harden the laminate into a board with a resin binder or the like, but the cost for making the board increases and at the same time,
Since the binder deteriorates the degree of vacuum, it is necessary to completely remove the binder before evacuation of the inside of the heat insulating wall, and there is a drawback that the heat treatment for this purpose is required and the number of steps is increased.

Further, in the above-mentioned compaction filling method, after the heat insulating material is filled, the welding is performed without vacuum leak in a state where the pressure necessary for the material compaction is applied to the outer container and the heat insulating material is on the back surface of the welded portion. Had to be carried out, and there was a drawback that the construction was very troublesome.

[0006]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and can be inserted without breaking a laminate of a metal foil and an inorganic fiber sheet without forming a board, In addition, the purpose of the present invention is to obtain a method for easily manufacturing a vacuum heat insulating product by making sure that no stress is applied to the welded portion and that the heat insulating material does not come into contact when performing welding to withstand a vacuum leak.

[0007]

That is, the method for manufacturing a vacuum heat insulating product according to the present invention comprises a double wall 1 having an outer wall 1A and an inner wall 1B.
In the manufacturing method of the vacuum heat insulation product 1 which is made of C, the heat insulating material 2 is inserted into the double wall 1C in which the inner wall 1B side is the high temperature side and the outer wall 1A side is the low temperature side, and the inside of the double wall 1C is evacuated,
The inner container 3 serving as the inner wall 1B is covered and supported on a supporting jig 4 which is in contact with the inner surface of the inner container 3 without any gap, and an inorganic fiber sheet 5A and a metal foil 5B having a small heat emissivity are provided on the outer surface of the inner container 3. The heat insulating material 2 made of a laminated body of the laminated body 5C and the inorganic fiber board 6 which are alternately laminated is arranged, and then the inner diameter is made smaller than the thickness of the heat insulating material 2 and the compression rate when fitted is large with respect to vacuum. An outer container 7 having an inner diameter that provides a compression ratio approximately equal to atmospheric pressure is externally fitted to the inner container 3 while the outer wall 1A is forcibly fitted while the heat insulating material 2 is being compressed. The opening edges 3A and 7A of the container 7 are hermetically welded to each other.

[0008]

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

In such a vacuum heat insulating product, a heat insulating material 2 composed of a laminated body 5C and an inorganic fiber board 6 which are alternately laminated on the inner wall 1B side of the inorganic fiber sheet 5A and the metal foil 5B having a small heat emissivity. Need to be placed. Therefore, in order to prevent the damage of the laminated body 5C, in the present invention, first, the inner container 3 serving as the inner wall is supported from the inner surface by the supporting jig 4, and the inorganic fiber sheet 5A and the metal foil 5B having a small heat emissivity are provided on the outer surface thereof. The laminated body 5C in which and are alternately laminated is arranged, and the inorganic fiber board 6 is arranged on the outer side thereof to provide the heat insulating material 2
Then, the inorganic fiber board 6 on the outer side of the heat insulating material 2 is used as a cushioning material to cover the outer container 7 serving as an outer wall. 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 is not damaged.

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

Since the inner surface of the inner container 3 is supported by the supporting jig 4, the outer container 7 serving as the outer wall 1A is not deformed even if it is forcibly fitted. Then, after the external fitting, the openings of the outer container 7 and the inner container 3 are hermetically welded. At this time, since the welded portions are the open end faces of the inner container 3 and the outer container 7, the influence of stress is small and the heat insulating material 2 is hardly contacted, so that highly reliable welding against vacuum leakage 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, the thickness of the vacuum insulation wall 1C was 37 mm, and a vacuum insulation container having an inner surface with a high temperature was manufactured.

Example 1 First, as shown in FIG. 2, as the inner container 3 to be the inner wall 1B, an integrally molded upper opening type container made of a stainless steel plate having a thickness of 1 mm was formed. Width of 922m (= 1000mm-37mm ×)
2-1mm x 4 (container thickness), height 1662mm (= 1700mm-37)
mm-1mm (same), depth 522mm (= 600mm -37mm x 2-1mm
The inner container 3 was covered and fixed on the support jig 4 of × 4). Next, as shown in FIG. 3, a heat insulating material having a total thickness of 44 mm, which is composed of a laminated body 5C in which an inorganic fiber sheet 5A and a metal foil 5B having a small heat emissivity are alternately laminated on the outer surface of the inner container 3 and an inorganic fiber board 6. Two were laminated.

An outer container 7 which is also an upper opening type integrally molded container and has an outer width of 1000 mm, a depth of 600 mm and a height of 1700 mm and serves as an outer wall 1A is formed by compressing the heat insulating material 2 as shown in FIG. It was forcibly fitted. The outer container 7 was provided with an outwardly curved curve 7B so as not to catch the inorganic fiber board 6. Further, reference numeral 9 in the drawing denotes a jig for pushing 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 are hermetically welded to each other in a completely fitted state. At this time, the welding portions of the opening edges 3A and 7A were the flange-shaped portions 7C outside the container 1 as shown in the drawing, and were located at positions where the heat of welding was not directly applied to the heat insulating material inside.

[Second Embodiment] The outer container 7 in the first embodiment.
As shown in FIG. 6, a vacuum heat insulating product was manufactured in the same manner except that a linear cut end was used and a slide plate 8 made of a silicon resin sheet was inserted at the open end.

Comparative Example 1 A vacuum heat insulating container having the same size as in Example 1 was manufactured by the conventional inner container inserting method. That is,
On the inner surface of the outer container that constitutes the outer wall, a layer of inorganic foil and an alternating laminated body of inorganic fiber sheets and a layer of inorganic fibers are fixed with a binder, and a heat insulating material as a board is arranged and fixed, and the inner wall of the vacuum heat insulating product is fixed inside. A vacuum heat insulating container was manufactured by inserting the inner container constituting the above and hermetically welding the openings of the outer container and the inner container.

[Comparative Example 2] A vacuum heat insulating container having the same size as that of Example 1 was manufactured by a conventional compaction filling 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 seal the opening. A vacuum heat insulation container was manufactured by welding to.

Next, the time required for filling the heat insulating material 2 and the presence or absence of dented deformation of the inner and outer walls due to the atmospheric pressure after the vacuum treatment were compared between Examples 1 and 2 and Comparative Examples 1 and 2 to find that the heat insulating material was filled. Regarding the time, the compaction filling method of Comparative Example 2 required 3 hours, whereas in the case of Examples 1 and 2, it was only 1 hour and could be shortened to 2 hours. In the method of the present invention, the outer wall 1A,
Since the inner and outer containers 3 and 7 to be the inner wall 1B are molded in advance, the time for container production is shortened as compared with Comparative Example 2,
The time required to manufacture the container has been reduced by about 2 hours. In addition, the time required to evacuate the interior of the double wall was 1/4 that of Comparative Example 1 because no binder was used in the method of the present invention. In addition, no concave 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, according to the present invention, as compared with the method for producing a vacuum heat insulating product by the inner container press-fitting method, it is not necessary to solidify the heat insulating material composed of the laminated body with the resin binder. It becomes unnecessary. further,
The time required to remove the resin binder that adversely affects the vacuum is also unnecessary, and the vacuum exhaust processing time can be shortened to 1/4.

Further, as compared with the consolidation filling method, the time required to complete the filling of the heat insulating material is shortened to 1/3 because the step of welding the outer container after the filling is unnecessary. Therefore, the time for manufacturing the container excluding the filling operation is shortened by 2 hours. Further, since the inner and outer containers are welded on the back surface of the welded portion without the heat insulating material, reliable welding can be performed, and highly reliable welding without vacuum leak can be achieved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a heat insulating product (container) on which the present invention is based.

FIG. 2 is a cross-sectional view showing a state in which a container-shaped body that serves as an inner wall is supported.

FIG. 3 is a cross-sectional view showing a state in which a heat insulating material is arranged on the outer surface of the container-shaped body which is the inner wall.

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

FIG. 5 is a cross-sectional view showing a state in which the openings of the container-like body forming the inner and outer walls are welded.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulation product 1A ... Outer wall 1B ... Inner wall 1C ... Double wall 2 ... Insulation material 3 ... Inner container 3A ... Opening edge of container-like body used as inner wall 4 ... Support jig 5A ... Inorganic fiber sheet 5B ... Thermal emissivity 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-like portion 8 ... Sliding plate

Claims (1)

[Claims] 1. A double wall 1C having an outer wall 1A and an inner wall 1B, in which a heat insulating material 2 is inserted into a double wall 1C in which the inner wall 1B side is the high temperature side and the outer wall 1A side is the low temperature side, and the inside of the double wall 1C is In the manufacturing method of the vacuum heat insulation product 1 formed by vacuuming, the inner wall 1B
The inner container 3 to be covered is supported on a supporting jig 4 which is in contact with the inner surface of the inner container 3 without a gap, and the inorganic fiber sheet 5A and the metal foil 5B having a small thermal emissivity are alternately provided on the outer surface of the inner container 3. The heat insulating material 2 composed of a laminated body of the laminated body 5C and the inorganic fiber board 6 is arranged, and then the inner diameter is made smaller than the thickness of the heat insulating material 2 and the compression rate when fitted is the atmospheric pressure against vacuum. An outer container 7 having an inner diameter such that the compression ratios are substantially equal to each other is forcibly fitted while compressing the heat insulating material 2, and the inner container 3 and the outer container 7 are completely fitted together. A method for manufacturing a vacuum heat insulating product, characterized in that the respective opening edges 3A and 7A are welded in an airtight manner.