JPS58138844A - 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 The present invention relates to a flat panel-shaped vacuum insulation material.

Currently, there are many types of insulation materials, but most of them take advantage of the low thermal conductivity of the material they are filled with, and this method naturally has its limitations.

As an alternative to this, there is a vacuum insulation method that creates a high vacuum of about 10 Torr inside the insulation layer to prevent heat transfer due to mutual collisions between molecules, but due to the 11 force-resistant structure of the vacuum container, Application is limited to containers with curved structures such as thermos flasks and dual-bottles, which have a cylindrical structure, a spherical structure, or a combination structure of a cylinder and a spherical structure.

However, most structures that require insulation, such as refrigerators, heating cabinets, furnaces, bathtubs, and houses, have a flat plate shape or a box structure that combines flat plates. It is difficult to construct a container, and if it is strengthened by plate thickness or rib material, heat conduction loss through the corners will increase and the insulation function will be impaired.-1-1 Product cost ,
This is disadvantageous in terms of product weight, so flat vacuum insulation materials are not used at all.

Conventional known examples are explained with reference to FIGS. 1 and 2. 1+'z cylindrical cylinder, 2-1 is the inner bottom of the inner cylinder 1 and is hemispherical with a convex negative pressure side 3, The vertical side of each of these, that is, the vacuum gap side, has a mirror finish with low emissivity to prevent radiation heat transfer. 2 is a cylindrical outer cylinder,
2-1 is the outer bottom of the outer cylinder 2 and is formed into a truncated sphere convex to the inside, that is, to the negative pressure side, and the inner surface of each of these, that is, the vacuum gap side, is as follows.
Like the inner cylinder I, it has a mirror finish to provide radiation heat transfer protection. 3 is the inner cylinder, the neck connecting ■ and the outer cylinder 2, 4 is the lid, and 5 is an adiabatic space with a vacuum of 1O-2 to 10"l' Or r, which extends the mean free path of molecules and to prevent mutual collision of the containers, reduce heat transfer loss, and radiant heat transfer is reduced by the mirror finish of the opposing containers.
Heat conduction due to the temperature difference between the inner cylinder 11 and the cylinder 2 occurring in the neck 3 can be reduced by narrowing the neck 3 and making the plate thinner, which is effective in insulating the entire container. Also, in terms of structural mechanics, it is a combination of a cylinder, a hemisphere, and a broken ball, and the entire container has a thin board structure that can maintain the vacuum cylinder pressure, so it is not only effective for insulation but also for workability, cost, and weight. It will be advantageous.

However, when this is constructed as a vacuum insulation material in the form of a flat panel made of thin plates, even if the panel is small, the The thin plate structure alone cannot maintain a flat vacuum space because it deforms and collapses under load. In order to prevent this, if the construction is made of thick metal material and reinforced rib material, the heat conduction loss through part of the four side corners corresponding to the neck 3 of the conventional example will increase, and it will also cause defects in terms of cost and weight. The reality is that this type of insulation cannot be applied.

The present invention has been made to improve the above defects.

In other words, a thin sheet metal material made of an alloy of iron, nickel, and chromium is used for the rib plate, and a fibrous or powder spacer that undergoes compression deformation at a certain rate is enclosed as a pressure-resistant structural material to maintain space. This relates to a flat plate-shaped vacuum heat insulating material in which a part of stainless steel is deformed by creating a vacuum in the void.

An embodiment of the present invention will be explained with reference to figures 3 to 11. 6 is a drawn outer plate, which is shallowly press-formed with a small corner radius, and is made of iron, nickel, and chrome. , or an alloy containing either iron, nickel, or chromium.

6-1 is a flange of the drawn outer plate 1, 6-2Lt is a drawn hole for connecting and welding a pipe, and 7 is a flat plate-like ultra-thin outer plate, and the outer dimensions other than the thickness direction are the same. The plate thickness is made thinner than the drawn outer plate 6 to simultaneously provide flexibility during vacuum pressurization and the function of preventing heat conduction loss through the metal material on the outer periphery of the outer plate. Further, the same alloy material as that of the aperture outer plate 6 is used as the material. The reason why the alloy material is used for the aperture plate 6 and the ultra-thin outer plate 7 is that the thermal conductivity is a fraction of that of iron.
Heat conduction loss through the outer periphery of the plate is simultaneously prevented by thinning the plate. In addition, this alloy material generates only a small amount of gas on the surface and inside of the material after processing such as cleaning and baking, so there is little deterioration in the degree of vacuum, and it also has excellent corrosion resistance and strength, and does not have holes even when made into a thin plate. This is because it has no defects such as, and has good workability in JJ drawing press, welding, etc., and can be effective under all conditions. 8 is a glass wool mat, which is made of pure glass wool fibers that do not use any additives such as curing agents or adhesives, and the fiber direction is perpendicular to the thickness direction of the glass wool mat, which is configured in a flat plate shape, that is, the direction in which heat conduction occurs. Stack them randomly in the same direction.

To construct this structure, the glass wool fibers 8-1 are cut into lengths and then sucked into a vacuum-covered duct, so that the glass wool fibers 8-1 are randomly laminated parallel to the suction surface. ,)if l! ', it becomes a point contact, increasing the contact thermal resistance and making it advantageous in terms of insulation. 8
-2 is a penetration fiber in which a part of the outside of the laminated glass wool fibers 8-1 is sewn in the right angle direction, and as a result, it has a low density like cotton and has a high compression deformation of more than 90% when vacuum pressure is applied. 50% of the compressive deformation amount at high density
Harden the glass wool into a mat with less and less. This penetration fiber 8-2 is several dozen trees/a! If you sew it to a certain degree, the density will be the highest, and this pene I ration fiber 8
The direction -2 coincides with the heat transfer direction, but the diameter of commonly commercially available fibers is around 10 microns, and the cross-sectional area ratio of penetration fiber 8-2 in the heat transfer direction area is 3 in this case.
It is as small as X l O'% and can be ignored in terms of heat transfer. In this way, the glass wool mat 8 is made of pure glass fiber without binder such as resin, and can have a low compression deformation rate, and can prevent gas generation. 9
is a vacuum pipe for connection to a vacuum pump (not shown), and the aperture is connected to the plate 6 or the flat plate 7 by welding. 10 is a needle for sewing in the penetration fiber s-2, and 1.0-1 is a hook for hooking the glass wool fiber 8-1. By arranging a plurality of these fibers and driving them into a group of glass wool fibers 8-1, the glass wool mat 8 is constructed.

11 is a flat plate-shaped vacuum insulation material after evacuation and sealing off a part of the vacuum pipe 9.

To construct a flat vacuum insulation material in the hanging part shrine, a vacuum pipe 9 is hermetically welded to the throttle hole 6-2 of the throttle outer plate 6. The ultra-thin board was washed together with board 7, and several hundred degrees Celsius
Baking treatment is performed to degas the inner surface of the vacuum container, in particular, to prevent gas generation after the vacuum seal is cut. At the same time, glass wool pine!・8 also undergoes baking treatment at around 500℃ in a separate process. Thereafter, a glass wool mat 8 is placed inside the concave portion of the plate 6, covered with an extremely thin outer plate 7, and the flange 6-1 and the outer periphery of the extremely thin outer plate 7 are hermetically welded. This welding method is performed by resistance welding, electric r-beat welding, etc., which can withstand high-temperature furnaces and is suitable for thin plate materials.

This assembled member is further placed in a furnace, a vacuum pump is connected to the evacuation pipe 9, vacuum baking is performed, and impurities that have been mixed in during the assembly 1γ process are vaporized and discharged.
When the degassing is completed and the target degree of vacuum is reached, the vacuum pipe 9 is cut under pressure. In this case, the vacuum pipe 9 is cut by applying high pressure from the main part. Pressure sealing of clean metal surfaces is performed at the same time to maintain airtightness.Also, when the vacuum pump is activated, high pressure of IKti/crA is applied to the inside and outside of the panel, and the internal pressure between the aperture outer plate 6 and the ultra-thin outer plate 7 is applied. The glass wool mat 8 is compressed.

Although this glass wool mat 8 has a high density, its thickness is slightly deformed, so you can rest assured that it will absorb this and the ultra-thin outer plate 7
The aperture has a flat plate shape and is thinner than the plate 6, and has a small moment of inertia of area and is flexible, and only this is deformed into a concave shape.
to prevent warpage, deflection, and warping of the entire vacuum insulation material 11.
It does not cause waviness and can be easily incorporated as a heat insulating material.

With regard to the heat conduction of the glass wool mat 8, due to the heat insulation function of the flat panel configured as described above, thin fibers of around 10 microns in the direction perpendicular to the heat conduction direction are laminated in point contact, and the apertured outer panel 6 and Assuming that the gap between the extremely thin plate and the plate 7 is 1 m, the number of times of contact in the heat transfer direction will be 1,000 times, and the contact thermal resistance will be extremely large between this number of times and the condition of point contact. Further, the penetration fibers 8-2 are configured such that the fiber direction is in the heat transfer direction, but as described in 01f, the area composition ratio is small and can be ignored, so the heat conduction loss of the entire glass wool mat 8 is small and the heat insulation effect is large.

Furthermore, the glass wool fibers 8-1 function as multilayer heat insulation to prevent radiation heat transfer.

In addition, the heat conduction loss due to one round of heat passing through the glue between the aperture outer plate 6 and the ultra-thin outer plate 7 at the corners is due to the strength of the aperture outer plate 6 and the ultra-thin outer plate 7 as a pressure-resistant container. Because it is unnecessary and is simply a vacuum-blocking surface, it has a structure that can be made as thin as the manufacturing limit to achieve the purpose, and it has a low thermal conductivity that is a fraction of that of iron made of iron, chromium, and nickel alloy materials. reduced.

A flat panel that is evacuated in this way can greatly reduce heat transfer, heat conduction, and radiation losses, and can greatly improve its insulation capacity.

At the same time, since the vacuum space inside the panel is composed of a glass wool mat 8 made of fine fibers, the typical dimension of the void is 1.
1 1 ゛, the molecular [η stroke is shortened and 1 It also has the effect of making it easier to maintain the degree of vacuum.

As another example, as shown in FIG.
- Even if a powder spacer 12 made of pearlite or the like is incorporated in place of 8, the drawn outer plate 6 and flat plate 7 can be constructed with exactly the same function, absorbing the compressive deformation during vacuum pressurization and increasing the effect. I can do it.

As described above, it is possible to obtain a flat plate-shaped vacuum heat insulating material which has a simple structure, has a light area, is excellent in terms of manufacturing cost, and has a tremendous effect on heat insulation ability and flange durability.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a perspective view of a conventional thermos flask, FIG. 2 is a vertical sectional view of FIG. 1, and FIG. 3 is a perspective view of the vacuum insulation material 1 of the present invention. The figure shows the aperture shown in Fig. 3 as a perspective view of the inner surface structure of the plate, Fig. 5 shows a vertical view of the glass wool mat, Fig. 6 shows an enlarged view in the direction of Fig. 5, and Fig. 7 shows the inner structure of the plate. 5 is an enlarged view in the B direction, FIG. 8 is an explanatory diagram of the longitudinal cross-sectional structure of the vacuum insulation material after assembly, FIG. 9 is an explanatory diagram of the longitudinal cross-sectional structure of the vacuum insulation material after vacuum sealing, and FIG. The figure shows a hooked needle for penetration, and FIG. 11 is an explanatory view of the vertical cross-sectional structure of the vacuum heat insulating material after vacuum sealing and cutting, in which the powder heat insulating material is sealed. 6... Diaphragm outer plate, 7... Ultra-thin plate outer plate, 8... Glass wool mat, 9... Vacuuming pipe, IO...
- Needle, 11... Vacuum insulation material, 12... Powder insulation material. 2 -1 Stem 31iEl Stem 40 Y50 11;6 Figure'i! ;'7 Figure □ Stem 8 Figure 1 Continuation of page 1 of a certain to product 0 Inventor Masayuki Shibayama Inside the Tochigi Plant of Hitachi, Ltd., 800 Oaza Tomita, Ohira-cho, Shimoga-gun, Tochigi Prefecture

Claims (1)

[Claims] 1. A vacuum drawer on the convex side of the drawn thin plate (6) made of an alloy of iron, nickel, and chromium, or an alloy material containing at least one of iron, nickel, or chromium. The pipe (9) is welded, and the concave side is made of high-density glass wool pine (8) made of fine glass fiber. Cover with an ultra-thin outer plate (7) that is even thinner than the outer plate (6), and connect the aperture to the vertical flange (6-1) of the plate (6) and around the ultra-thin outer plate (7). I5 is hermetically welded, the inside of the panel is evacuated, and the ultra-thin plate (7) is deformed according to the amount of compression deformation of the glass wool mat (8) when vacuum is applied. After achieving the degree of vacuum, the A vacuum insulation material characterized by cutting a part of the pipe (9) under pressure to seal the vacuum. 2. Inside the vacuum panel, powdered insulation IA' is used instead of glass wool pine l-(8) made of fine fibers.
The flat vacuum insulation material according to claim 1, characterized in that (12) is enclosed as a spacer. 3. Claim 1, characterized in that the welding of the pipe (9) and the welding of the flange (6-1) and the ultra-thin outer plate (7) are made to withstand baking treatment temperatures;
and vacuum insulation JjA according to item 2.