JPS6166068A - Vacuum heat-insulating material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to a flat vacuum heat insulating material.

[Background of the invention]

Conventionally, as a flat vacuum insulation material, a powder or fibrous filler is installed inside as a spacer to reduce the mean free path of the molecules so that it can be used in a low vacuum side, and to provide vacuum pressure resistance. Containers made of plastic or metal-deposited laminate sheets are used.

Conventional device using powder as an internally filled spacer
The material described in No. 7-184880 has a problem in that the material is densely structured and the contact area between the powder bodies is large, resulting in a decrease in contact thermal resistance and inability to exhibit sufficient heat insulation function.

As an alternative to this, the one described in JP-A-58-127085 is filled with fibrous spacers. This conventional example will be explained with reference to FIGS. 2 to 5.
1a is a laminate film, 1a is a metal film, and 1b is a plastic sheet serving as the inner surface and has a heat-sealing function.

1C is the outer plastic sheet, and each sheet is
It's glued together like a sandwich. 2#i, an aggregate of fibers that is often used especially for vacuum applications, has a low density (approximately 10 Kf/rr? in the case of glass wool) under atmospheric pressure and is composed like cotton. When subjected to a pressure of 1 to 9/-, it is compressed to several tenths.

To construct a vacuum insulation material using the hanging parts, first, two laminate films 1 are placed facing each other so that the inner surface becomes the plastic sheet 1b, and the outer periphery of six sides is heat-sealed to form a bag shape. Fill the low-density glass cooler and place it in a vacuum tank (
(not shown), and after evacuation, the opening is heat-sealed and the outside is returned to the atmosphere, the glass wool 2 is compressed and deformed to several tenths, and the laminate sheet 1 is also deformed accordingly.
Many wrinkles occur on the surface, and most of the wrinkles are caused by the laminate sheet being bent closely, causing cracks in the metal film 1a, which causes the laminate sheet to lose its gas barrier properties and become unable to maintain vacuum. there were.

In addition, in order to achieve the target thickness of the heat insulating material, several tens of times as much glass wool 2 was required, and in reality, it was impossible to work unless the finished product was extremely thin.

Furthermore, another method is to harden the glass wool 2 with an adhesive to make it resistant to pressure, but this has the problem of filling the spaces between the fibers with the adhesive, reducing the contact thermal resistance and greatly reducing the insulation ability. be.

In addition, in the case of powder, in order to prevent the powder from scattering, a double packaging operation is required in which the powder is placed in a small bag in advance and then filled into a vacuum container.

[Purpose of the invention]

An object of the present invention is to solve the above-mentioned problems.

[Summary of the invention]

As a means of achieving this, a laminated film is constructed into a bag shape,
A high-density fiber mat with little compression deformation is placed inside, and the interior is evacuated and sealed.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 and 6 to 9. Reference numeral 6 indicates a high-density fiber mat, 6a indicates fibers randomly laminated in a direction perpendicular to the heat transfer direction, and 6b indicates a high-density fiber mat. teeth,
This is a Benetrene fiber that is sewn in a direction perpendicular to the laminated fiber 3a, so that the low-density laminated fiber 3a undergoes less compressive deformation when vacuum pressurized. This fiber material has a high elastic modulus and is particularly effective when used as a glass core. 1 is a plastic laminate sheet,
Similar to the conventional example, a metal film is partially incorporated. , 4 is a getter, which is a gas adsorbent to ensure long-term vacuum pressure.

To construct a vacuum heat insulating material using such members, first, the periphery of the laminate sheet 1 is heat-sealed into a bag shape, and the high-density fiber mat 3 and getter 4 are filled inside, as in the conventional example. In this case, it is sufficient to incorporate fiber mat 5Fi, which has little compression deformation and has the same thickness as the target thermal material thickness, so that it can be easily inserted without causing unnecessary distortion to the bag of laminate sheet 1. After that, it is placed in a vacuum tank, and after evacuation, the opening is heat-sealed, but since the opening is narrow, it is simple and does not require an extra sealing dimension of the laminate sheet 1. After this, the outside is returned to atmospheric pressure and completed.
Even when subjected to vacuum pressure, the fiber mat 4 undergoes little compressive deformation and wrinkles.

〔Effect of the invention〕

In the fiber mat 3 of the vacuum insulation material constructed as described above, since the fibers 3a are random in the heat transfer direction, the heat flow path becomes zigzag, and the fiber autobiographical thermal resistance and the interfiber contact thermal resistance act alternately, and the spacer Greatly improves insulation function. or,
Since the penetration fibers 5b, which are in the heat transfer direction, can be made in a very small number and have a high density, the heat transfer loss due to this is small. In addition, the internal loss is small enough to be ignored even in the low vacuum region where the fiber 6a narrows the void size and the mean free path of molecules is small, so it is a material with extremely excellent heat insulation function. can.

10,000, since the fiber mat 5 has little compression deformation,
The work of inserting the fiber maturo and the heat-sealing work in the vacuum tank are easy, and the laminate film 1 can be made smaller, reducing wasted material. Furthermore, during final finishing, the laminate film does not have wrinkles that would cause extreme adhesion, so the internal metal film does not crack, and the internal vacuum is maintained for a long period of time, reducing the defect rate. In addition, since the flatness is good, it has the effect of being easy to assemble and having an excellent appearance.

Furthermore, unlike a powder, the fiber mat of the present invention does not require double packaging and can be produced extremely easily.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a completed product of the vacuum insulation material of the present invention, Fig. 2 is a cross-sectional view of a conventional laminate film, Fig. 6 is a cross-sectional view of a conventional example before evacuation, and Fig. 4 is a cross-sectional view of a conventional laminate film. Figure 6 is a sectional view of the finished product obtained by vacuuming and sealing the product, Figure 5 is an enlarged view of the bent portion of the laminate film in Figure 4, Figure 6 is a perspective view of the fiber mat of the present invention, and Figure 7 8 is an enlarged side view of FIG. 6, and FIG. 9 is a sectional view before vacuuming of the present invention. 1... Laminate film, 1a... Metal film, 1b
...Plastic sheet, 1C...Plastic sheet, 2...Fiber aggregate, 6...Fiber mat, 6
a... Fiber, 3b... Penetration fiber, ¥,
1 口￥, a ￥, 4 口￥-5 口'tl-6 fig. 1 mouth 8 eyes

Claims (1)

[Claims] 1. A vacuum heat insulating material comprising a laminate film formed into a bag shape, a fiber mat placed inside the bag, and an internal space evacuated. 2. The vacuum according to claim 1, characterized in that fibers are randomly laminated at right angles to the heat transfer direction, and a high-density fiber mat is provided by sewing penetration fibers at right angles thereto. Insulation. 3. The vacuum insulation material according to claim 1, wherein the fiber material is glass wool.