WO2012176880A1

WO2012176880A1 - Vacuum insulated panel

Info

Publication number: WO2012176880A1
Application number: PCT/JP2012/065997
Authority: WO
Inventors: 松田　真次
Original assignee: 株式会社松田技術研究所; 日本石油輸送株式会社
Priority date: 2011-06-24
Filing date: 2012-06-22
Publication date: 2012-12-27
Also published as: JP2013007439A; JP5890973B2

Abstract

A vacuum insulated panel that is lightweight, thin and has excellent insulating properties. A tightly sealed space is formed by disposing a pair of side panels to face each other and disposing four frame pieces along the various sides of the side panels. Using an exhaust port, the tightly sealed space is evacuated. In the tightly sealed space, an inner panel of stainless steel, etc. is disposed to be substantially parallel to the side panels. Multiple protrusions are disposed on the inner panel. As a result of the protrusions contacting the inner surface of the side panel with the tips thereof, the side panels are supported. The protrusions are formed from a material with a lower thermal conductivity than the inner panel such as glass or ceramic.

Description

Vacuum insulation panel

The present invention relates to a vacuum heat insulation panel formed by evacuating the internal space of a hollow panel.

Insulation panels are used for housings such as refrigerators and cold storage containers, and wall materials for air transport containers. 2. Description of the Related Art Conventionally, a heat insulating panel in which a heat insulating material such as urethane foam or polystyrene is embedded between a pair of side plates is known. However, when producing a heat insulating panel using these heat insulating materials, a very thick heat insulating material is required to obtain sufficient heat insulating properties.

Also, a technique for improving the heat insulation of such a panel by evacuating the internal space of the hollow panel is conventionally known. Such a heat insulation panel is called a vacuum heat insulation panel. According to the vacuum heat insulation panel, the heat insulation can be improved as compared with the case where only the heat insulating material is used. However, in the vacuum heat insulation panel, the side plates are deformed due to the difference between the atmospheric pressure and the atmospheric pressure in the internal space, the side plates come into contact with each other, and heat may be directly conducted between the side plates. For this reason, it is desirable to provide the vacuum heat insulation panel with a reinforcing means for suppressing such deformation.

For example, in the technique of Patent Document 1 below, the deformation of the vacuum heat insulating panel is suppressed by laminating uneven steel plates (see paragraph [0015] of FIG. 1, FIG. 1 and the like).

Japanese Patent Laid-Open No. 2005-114028

However, the technique of Patent Document 1 has a drawback that the weight of the vacuum heat insulation panel is increased because a plurality of steel plates are used.

Also, since heat is conducted between the two side plates via the steel plate, there is a drawback that the heat insulating performance of the vacuum heat insulating panel is deteriorated.

Furthermore, since such steel plates are laminated, there is a disadvantage that the thickness of the vacuum heat insulation panel cannot be reduced sufficiently. For example, a case where a shipping container is manufactured using such a vacuum heat insulating panel can be considered, but the outer dimensions of the shipping container are often defined in advance. For this reason, the larger the thickness of the vacuum heat insulation panel, the smaller the internal volume, and the load capacity decreases.

An object of the present invention is to provide a vacuum heat insulation panel that is light in weight, small in thickness, and excellent in heat insulation performance.

The vacuum heat insulation panel according to the present invention includes a sealed space formed by using a pair of side plates opposed to each other and four frame members arranged along each side of the side plates, and evacuating the sealed space. And an air pressure inside and outside of the sealed space by contacting an inner plate and an inner surface of at least one of the side plates disposed in the sealed space substantially parallel to the pair of side plates. In order to suppress the deformation of the pair of side plates due to the difference, the inner plate has a plurality of protrusions, and the protrusions are made of a material having a lower thermal conductivity than the inner plate. It is formed.

In the present invention, the protrusions are arranged in a state of being inserted through through holes provided in the inner plate, and both end portions of the protrusions respectively contact the inner surfaces of the pair of side plates. It is desirable to touch.

In the invention of the present application, it is desirable that each of the protruding portions has a substantially conical shape at each tip portion that abuts on the side plate.

In the present invention, it is desirable that the protrusion is formed of glass or ceramic.

In the present invention, it is desirable that one or more through holes for weight reduction be provided on the side surface of the inner plate.

In the present invention, the frame member is bent at an obtuse angle at the side portions sandwiching the central portion of the flat plate, and the end portions of the side portions are bent so as to be parallel to each other. It is desirable that the corresponding side plate is in surface contact and a projection provided on each side plate is brought into contact with the vicinity of the boundary between the central portion and each side portion.

According to the present invention, the inner plate is disposed substantially parallel to the pair of side plates, the plurality of protrusions having lower thermal conductivity than the inner plate are disposed on the inner plate, and these protrusions are brought into contact with the side plates. As a result, the deformation of the side plate due to the difference between the atmospheric pressure of the internal space and the atmospheric pressure is suppressed. For this reason, according to this invention, the contact area of a projection part and a side plate can be made very small.

Therefore, in the vacuum heat insulation panel according to the present invention, there is very little heat conducted between the protrusion and the side plate. As a result, according to the vacuum heat insulation panel according to the present invention, very excellent heat insulation performance can be obtained.

It is a notional top view which shows the whole structure of the vacuum heat insulation panel which concerns on Embodiment 1 of this invention. It is AA sectional drawing of FIG. 1A. It is a schematic sectional drawing which expands and shows the part shown by the code | symbol X to FIG. 1A. It is a schematic side view of the projection part shown to FIG. 1B. It is an external appearance perspective view which shows notionally an example of the storage box produced using the vacuum heat insulation panel which concerns on Embodiment 1 of invention. FIG. 3B is a sectional view taken along line BB in FIG. 3A. It is an external appearance perspective view which shows notionally the other example of the storage box produced using the vacuum heat insulation panel which concerns on Embodiment 1 of invention. It is a fragmentary sectional view of the storage box shown in FIG. 4A.

Hereinafter, the vacuum heat insulation panel which concerns on embodiment of this invention is demonstrated using drawing.
Embodiment 1 of the Invention
1A and 1B are conceptual views showing the overall configuration of the vacuum heat insulation panel 100 according to the first embodiment, FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view taken along line AA in FIG. 1A.

As shown in FIG. 1A and FIG. 1B, in the vacuum heat insulation panel 100 of the present embodiment, the pair of

side plates

101 and 102 are disposed so as to face each other. An inner plate 110 is arranged between the

side plates

101 and 102. Further, the frame members 103 to 106 are disposed along the sides of the

side plates

101 and 102, and the

side plates

101 and 102 and the frame members 103 to 106 are fixed in close contact with each other. As a result, a sealed space 120 is formed by the

side plates

101 and 102 and the frame members 103 to 106. The sealed space 120 is evacuated to a high vacuum, for example, using the exhaust pipe 119. In the present application, “high vacuum” refers to a high vacuum defined by JIS (Japanese Industrial Standards), that is, a state where the atmospheric pressure is 10 ⁻⁵ Pa to 10 ⁻¹ Pa. Of course, the vacuum heat insulation panel 100 of this embodiment can be used even in a medium vacuum or a low vacuum.

Hereinafter, the configuration of the vacuum heat insulation panel 100 will be described in detail. 2A is an enlarged view of a portion indicated by reference numeral X in FIG. 1B, and FIG. 2B is a schematic side view of the protrusion shown in FIG. 1B.

As the

side plates

101 and 102, for example, a metal plate such as stainless steel can be used. In the present embodiment, the JIS SUS304-H (spring material) is used. Moreover, in this embodiment, the dimension of the

side plates

101 and 102 was set to 550 mm × 550 mm. The thickness of the

side plates

101 and 102 is preferably 0.2 to 0.8 mm, for example, but here it is about 0.5 mm. Further, as the

side plates

101 and 102, those in which the

outer side surfaces

101a and 102a are mirror-finished can be used.

As the frame material 103, for example, a metal plate such as stainless steel can be used. As shown in FIG. 2A, the frame member 103 is formed by bending the

side portions

103b and 103c sandwiching the central portion 103a at an obtuse angle and further bending the

end portions

103d and 103e so as to be parallel to each other. The

concave portions

101b and 102b of the

side plates

101 and 102 are brought into contact with each other in the vicinity of the boundary between the central portion 103a and the

side portions

103b and 103c. The total width W1 of the frame member 103 is, for example, 12 mm, and the length W2 of the contact portion with the

side plates

101, 102 is, for example, 5 mm or less. The

end portions

103 d and 103 e are in surface contact with the vicinity of the edge portions of the

side plates

101 and 102.

According to such a structure, since a high vacuum space is formed between the

side plates

101 and 102 and the

side portions

103b and 103c, the heat conduction between the

side plates

101 and 102 and the

side portions

103b and 103c is reduced. Can be suppressed. Further, most of the heat propagated from the

side plates

101 and 102 to the

end portions

103 d and 103 e can be radiated by the frame member 103. In order to improve the heat dissipation of the frame member 103, it is desirable to increase the total length of the frame member 103 (that is, the length of the conduction path when heat is conducted between the side plates 101 and 102). In this embodiment, since the inside of the sealed space 120 is set to a high vacuum, the vicinity of the central portion 103a is pressed from both sides by the

concave portions

101b and 102b due to the pressure difference between the inside and outside of the sealed space 120. Thereby, even if the overall length of the frame member 103 is increased, sufficient strength can be obtained. Any other shape may be used as long as the path length of the heat conduction is longer than the distance between the

side plates

101 and 102. Although only the frame member 103 is shown in FIG. 2A, the structures of the other frame members 104 to 106 are the same.

In the present embodiment, the JIS SUS304-H is used as the metal material of the frame members 103 to 106, and the thickness of each of the frame members 103 to 106 is about 0.2 mm. Then, by fixing these frame members 103 to 106 by seam welding or the like, the frame 109 of the vacuum heat insulating panel 100 as shown by the dotted line in FIG. 1A was assembled. Further, seam welding was performed along each side of the

side plates

101 and 102 to fix the frame members 103 to 106 and the

side plates

101 and 102 in close contact with the welded

portions

201 and 202. Seam welding is a type of resistance welding and is a method of continuously welding objects to be welded by rotating an electrode while applying pressure and energizing using a roller electrode. For fixing the frame members 103 to 106 and the

side plates

101 and 102, other fixing methods such as arc welding may be used. However, as such a fixing method, it is desirable to employ a method that does not generate gas. This is because if the gas leaks from the welded portion after evacuating the sealed space 120, the degree of vacuum is lowered and the heat insulating effect may be impaired.

As the inner plate 110, for example, a metal such as stainless steel can be used. In the present embodiment, the JIS SUS304-H is used as a material for forming the inner plate 110. The thickness of the inner plate 110 was about 0.2 mm. In order to improve heat insulation, the inner plate 110 is disposed so as not to contact the frame members 103 to 106.

The inner plate 110 is provided with a large number of through holes 111. The diameter of the through hole 111 is, for example, 6 mm. The protrusion 112 is inserted into the through hole 111. As shown in FIG. 2B, the protrusion 112 of the present embodiment includes a small-diameter columnar portion 112a (for example, 2 mm in height and 6 mm in diameter) and a large-diameter columnar portion 112b (for example, 1 mm in height and 8 mm in diameter). It is integrally formed so that one end surfaces may contact | connect. Furthermore, a small-diameter and substantially conical tip 112c (for example, 3 mm in height and 6 mm in diameter) is formed on the other end surface of the small-diameter cylindrical portion 112a, and a large-diameter and substantially conical on the other end surface of the large-diameter cylindrical portion 112c. 112d (for example, height 4mm, diameter 8mm) is integrally formed, respectively. In the present embodiment, these protrusions 112 are held by the inner plate 110 simply by inserting the small-diameter cylindrical portion 112a and the tip portion 112c into the through hole 111. In the sealed space 120, one tip 112 c of the projection 112 abuts on the inner surface of the side plate 102 to support the side plate 102, and the other tip 112 d of the projection 112 is connected to the side plate 101. The side plate 101 is supported by contacting the inner side surface.

The reason why the

tip portions

112c and 112d are substantially conical is to reduce the contact area between the projection 112 and the

side plates

101 and 102, thereby suppressing heat conduction. By suppressing the heat conduction between the protrusion 112 and the

side plates

101 and 102, it is possible to make it difficult for heat to be conducted between the

side plates

101 and 102 via the protrusion 112.

The protrusion 112 is formed of a material having a lower thermal conductivity than that of the

side plates

101 and 102 and the inner plate 110. In the present embodiment, the protrusion 112 is made of glass. Here, the thermal conductivity of the JIS SUS304-H, which is the material for forming the inner plate 110, is 18 W / mK (W is watts, m is meters, K is Kelvin), for example, whereas the thermal conductivity of glass is The rate is, for example, 0.7 W / mK.

In this way, according to the present embodiment, the protrusion 112 that can suppress deformation of the

side plates

101 and 102 due to evacuation in the sealed space 120 and has extremely low thermal conductivity is formed at low cost. be able to.

In addition, if the thermal conductivity is lower than that of the

side plates

101 and 102 and the inner plate 110, the protrusion 112 can be formed of a material other than glass. However, in the vacuum heat insulation panel 100 of this embodiment, the load on the protrusion 112 is about 15 kg at the maximum (the same is true in the low vacuum, medium vacuum, and high vacuum of the JIS). For this reason, it is desirable to form the protrusion 112 with a material that can obtain sufficient strength against such a load. For example, ceramic has a thermal conductivity of about 0.6 W / mK and has a sufficiently high strength, and thus is suitable as the protrusion 112 of the present embodiment. In addition, when the protrusion 112 is made of ceramic, there is an advantage that the protrusion 112 can be easily processed.

In this embodiment, the inner plate 110 is provided with a plurality of weight reduction through holes 113. In addition, by providing the weight reduction through-hole 113, air flow can be facilitated when evacuating the sealed space 120. The size and number of the through holes 113 for weight reduction are arbitrary. However, in order to reduce the weight of the vacuum heat insulating panel 100, it is desirable to increase the total area of the weight reduction through-holes 113 within a range in which there is no problem in the strength of the inner plate 110. For example, the diameter of the through hole 113 for weight reduction is 30 mm, and the pitch of the through hole 113 for weight reduction is 38 mm.

The exhaust pipe 119 is used to evacuate the sealed space 120. The type of the exhaust pipe 119 and the like are not limited, but it is desirable to perform a process that can maintain the inside of the sealed space 120 in a vacuum state (for example, the high vacuum of JIS) for a long period of time. In this embodiment, the exhaust pipe 119 has a double pipe structure, a stainless pipe having a diameter of about 10 mm and a length of about 1 mm is used as the outer pipe, and a copper pipe is used as the inner pipe. The exhaust pipe 119 was press-bonded after being evacuated, and the exhaust pipe 119 was pressure-bonded, and the outer end of the exhaust pipe 119 was welded. Thereby, the intrusion of atmospheric gas into the sealed space 120 can be prevented, and the sealed space 120 is maintained at, for example, the high vacuum of JIS.

3A and 3B are examples in which a storage box is manufactured using the vacuum heat insulating panel 100 of the present embodiment, FIG. 3A is an external perspective view, and FIG. 3B is a cross-sectional view along line BB in FIG. 3A.

As shown in FIG. 3A, the storage box 300 has a substantially regular hexahedron shape, and is manufactured using six vacuum heat insulation panels 100. In FIG. 3A, only three vacuum heat insulation panels 100-1 to 100-3 are shown.

As the frame body 301, for example, a hard foam resin is used. As shown in FIG. 3B, the frame body 301 covers the ends of the two adjacent vacuum heat insulation panels 100 (the vacuum heat insulation panels 100-1 and 100-2 in FIG. 3B) and the vicinity thereof, These two vacuum heat insulation panels 100 are fixed so that the planes are at right angles. Thereby, each side of the six vacuum heat insulation panels 100 can be fixed to another adjacent vacuum heat insulation panel 100 to produce a substantially regular hexahedron containing box 300.

Note that when the cargo is stored in the storage box 300 or when the cargo is taken out from the storage box 300, the vacuum insulation panel 100-1 may be removed by pulling the frame 301 upward in FIG. 3B.

FIG. 4A and FIG. 4B are other examples of the storage box created using the vacuum heat insulation panel 100 of this embodiment, FIG. 4A is an external perspective view, and FIG. 4B is a partial cross-sectional view.

4A and 4B, a box-shaped storage box body 401 having an upper opening 401a is formed by a single vacuum heat insulating panel. For this reason, the

side plates

402 and 403 and the inner plate 404 are each formed into a box shape by three-dimensional pressing. Then, the protrusion 112 is loaded on the inner plate 404 and accommodated in the outer side plate 402, and further, the inner side plate 403 is accommodated in the inner plate 404. The upper opening 401a of the storage box body 401 can be closed by a lid (not shown). As the lid, one having the same configuration as the vacuum heat insulating panel 100 as shown in FIGS. 1A to 2B can be used.

Hereinafter, the principle of the vacuum heat insulation panel 100 according to the present embodiment will be described.

When using the vacuum heat insulation panel 100 according to this embodiment, the inside of the sealed space 120 is set to, for example, a high vacuum (may be a medium vacuum or a low vacuum). For this reason, since heat conduction by the air convection in the sealed space 120 (heat conduction between the side plates 101 and 102) can be extremely reduced, sufficiently high heat insulation can be obtained.

On the other hand, when the inside of the sealed space 120 is made a high vacuum, the

side plates

101 and 102 tend to be deformed inward by the negative pressure of the sealed space 120. As a method for suppressing such deformation, a method using a high-strength side plate or a method using an inner plate can be considered. However, when a high-strength side plate is used in order to suppress this deformation, it is necessary to increase the thickness of the side plate, so that the total weight of the vacuum heat insulation panel 100 increases. Moreover, also when using the reinforcement means like the said patent document 1, since the weight of inner board itself is large, the total weight of the vacuum heat insulation panel 100 will become large.

On the other hand, in the present embodiment, a plurality of through holes 111 are provided in the inner plate 110, the protruding portions 112 are inserted into the through holes 111, and both ends of the protruding portions 112 are connected to the

side plates

101 and 102. It was supposed to be supported by contacting. For this reason, even if the inner plate 110 is formed very thin, the

side plates

101 and 102 can be sufficiently reinforced. Therefore, according to the present embodiment, it is possible to obtain sufficient strength while reducing the weight of the vacuum heat insulating panel 100.

According to the study of the present inventor, even if the inside of the sealed space 120 is a high vacuum, it was possible to obtain a sufficient strength only by using such a protrusion 112.

In the present embodiment, the protrusion 112 is formed of glass or the like, which is a material having lower thermal conductivity than the

side plates

101 and 102 and the inner plate 110. For this reason, it is difficult for heat to be conducted between the

side plates

101 and 102 via the protrusion 112, and therefore, a very excellent heat insulating performance can be obtained.

Furthermore, in this embodiment, the frame members 103 to 106 have a bent structure as shown in FIG. 2A, so that the heat dissipation of these frame members 103 to 106 can be enhanced. Obtainable.

As described above, the vacuum heat insulation panel 100 of the present embodiment makes the inside of the sealed space 120 in a vacuum state (high vacuum, medium vacuum, or low vacuum), and heat conduction through the protrusion 112 and the frame members 103 to 106. small. For this reason, even if the panel thickness is very thin, sufficiently high heat insulation performance can be obtained. That is, according to this embodiment, the vacuum heat insulation panel 100 with high heat insulation performance can be formed very thin. In the vacuum heat insulating panel 100 of this embodiment, the panel thickness was 11 mm, and the thermal conductivity between the

side plates

101 and 102 was 0.00030 W / mK. On the other hand, the thermal conductivity of the heat insulation panel using urethane foam is about 0.02 W / mK.

As described above, according to this embodiment, it is possible to provide a vacuum thermal insulation panel that is lightweight, has a small thickness, and is excellent in thermal insulation performance.

In the present embodiment, the protrusion 112 is inserted into the through hole 111 of the inner plate 110 and both end portions of the protrusion 112 are brought into contact with the

side plates

101, 102. As long as the structure supports the inner side surfaces of the

side plates

101 and 102 with protrusions having lower thermal conductivity than the plate 110, the effects of the present invention can be obtained even with other structures. For example, without providing the through-hole 111, it is good also as fixing a short projection part to the both-sides surface of the inner board 110, and making it contact | abut to the

corresponding side plates

101 and 102, respectively.

The vacuum heat insulating panel of the present invention can be used for heat insulating materials for various purposes such as transport containers, storage containers, refrigerators, freezers, vending machines, building wall materials, and heat shields for blast furnaces.

DESCRIPTION OF SYMBOLS 100 Vacuum heat insulation panel 101,102 Side plate 103-106 Frame material 109 Frame 110 Inner plate 111 Through-hole 112 Projection part 113 Lightening through-hole 119 Exhaust pipe 120

Sealed space

201, 202 Welded part by seam welding 300, 400 Containment box 301 Frame body 401

Claims

A sealed space formed using a pair of opposing side plates and four frame members arranged along each side of the side plates;
An exhaust port for evacuating the sealed space;
An inner plate disposed in the sealed space substantially parallel to the pair of side plates;
A plurality of protrusions provided on the inner plate in order to suppress deformation of the pair of side plates due to a pressure difference between the inside and outside of the sealed space by abutting on the inner surface of at least one of the side plates; ,
Have
The vacuum heat insulation panel, wherein the protrusion is formed of a material having a lower thermal conductivity than the inner plate.
The protrusion is arranged in a state of being inserted through a through hole provided in the inner plate,
Both end portions of the protrusions are in contact with the inner side surfaces of the pair of side plates, respectively.
The vacuum heat insulation panel according to claim 1.
3. The vacuum heat insulating panel according to claim 2, wherein each of the protrusions has a substantially conical shape at each tip portion that abuts on the side plate.
2. The vacuum heat insulating panel according to claim 1, wherein the protrusion is formed of glass or ceramic.
The vacuum heat insulation panel according to claim 1, wherein one or more through holes for weight reduction are provided on a side surface of the inner plate.
The frame material is
The side portions sandwiching the central portion of the flat plate are each bent at an obtuse angle, and the end portions of the side portions are bent so as to be parallel to each other,
At these ends, in surface contact with the corresponding side plate,
In the vicinity of the boundary between the central portion and each side portion, a protrusion provided on each side plate is in contact,
The vacuum heat insulation panel according to claim 1.