JPH08121684A - Filler for vacuum insulator - Google Patents

Abstract

PURPOSE: To obtain handling performance and constructing performance by embossing to integrate a laminated body so as to be wavy over the whole cross section and to be compacted to the density withstanding atmospheric pressure to vacuum. CONSTITUTION: A laminated body 3 formed by alternately laminating a large number of metallic foil 1 with a low heat radiation rate and silica group inorganic fiber sheets is integrated being embossed so as to be wavy over the whole cross section and to be compacted to the density withstanding atmospheric pressure to vacuum to form a filler for a vacuum insulator. Since the laminated body 3 formed by alternately laminating a large number of metallic foil 1 with a low heat radiation rate and silica inorganic fiber sheets 2 is embossed so as to be wavy over the whole cross section, each layer is integrated without using a binder by the action of the compressive deformation of the uneven part of this embossment, the restoring elasticity of the metallic foil, and the like, and a pressure withstanding property is displayed by compaction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a filler for a vacuum heat insulating material.

[0002]

2. Description of the Related Art Conventionally, vacuum heat insulators have been known as industrial heat insulators for heating furnaces and cool boxes (for example, Japanese Patent Laid-Open No. 5-8729).
2 gazette, Japanese Patent Application No. 6-99309 specification and drawings, etc.). As these vacuum heat insulators, as is generally known as super insulation, a laminated body in which a large number of metal foils with small radiant heat and thin silica-based inorganic fiber sheets are alternately laminated is filled in the vacuum heat insulator and sealed. , Some are configured to exhibit a high heat insulating effect by evacuating the inside.

By the way, the fillers laminated and filled inside these vacuum heat insulators have no pressure resistance, so that there is a drawback that the vacuum heat insulators are deformed when atmospheric pressure acts on the inner and outer surfaces after evacuation, and also the metal foil and silica. Since the inorganic type inorganic fiber sheets are not integrated, there is a defect that the handling property and heat insulating workability of a laminated body in which a large number of them are superposed are very poor.

In order to solve such a problem, the applicant of the present invention integrated a metal foil and a silica-based inorganic fiber sheet with a binder, and further made a consolidated board to a density capable of withstanding a pressure corresponding to atmospheric pressure against a vacuum. We proposed a filling material for vacuum heat insulators (Japanese Patent Application No. 6-99309 specification and drawings, etc.). Since this filler is fixed with a binder, handling and workability have been greatly improved compared to the past, and because the laminate is a consolidated board, deformation of the vacuum heat insulator after vacuum evacuation is completely prevented. Has the effect that can.

[0005]

However, in the case of the above method, the binder becomes outgas and adversely affects the vacuum state in the heat insulating body. Therefore, in order to ensure the heat insulating property of the vacuum heat insulating body, the binder is completely removed before the vacuum exhaustion. Since it is necessary to remove the binder, the gasification heat treatment time is long because the binder is removed, and the number of treatment steps for this is also increased.

[0006]

The present invention has been made for the purpose of solving the above-mentioned problems, and handling, workability, and deformation of the vacuum heat insulator after vacuum evacuation are completely prevented. At the same time, the purpose of the present invention is to provide a filling material for a vacuum heat insulator, which can significantly shorten the processing time during evacuation.

[0007]

That is, the filling material of the vacuum heat insulator according to the invention of claim 1 is a metal foil 1 having a small thermal emissivity.
And a plurality of silica-based inorganic fiber sheets 2 are alternately laminated, and the laminated body 3 is emboss-pressed and integrated so that the laminated body 3 is undulated over the entire cross section and is compressed to a density withstanding the atmospheric pressure against vacuum. It is characterized by becoming.

As the metal foil, a metal foil having a small heat emissivity, such as an aluminum alloy foil or a copper foil, is used.
As the silica-based inorganic fiber sheet, a glass fiber sheet, a ceramic sheet, a rock wool sheet or the like is used. The embossing press is a press for curving the laminate into a wavy pattern with uneven front and back surfaces to integrate the metal foil and the silica-based inorganic fiber sheet in a consolidated state.

In the filler for the vacuum heat insulator according to the second aspect of the present invention, a large number of metal foils 1 having a small thermal emissivity and silica-based inorganic fiber sheets 2 are alternately laminated and the laminate 3 is spread over the entire cross section. A layer 5 that is embossed so as to be wavy and is compressed to a density that can withstand the atmospheric pressure against vacuum, and a single layer 6 that is also made of an inorganic fiber sheet that is also compressed to a density that withstands the atmospheric pressure against vacuum are integrated. It is characterized in that they are laminated one on top of the other.

A filler for a vacuum heat insulator according to a third aspect of the present invention is the filler for a vacuum heat insulator according to the first or second aspect, wherein a large number of minute through holes 1A are formed in the metal foil 1 having a small thermal emissivity. Are provided in a uniformly dispersed form.

[0011]

In the invention according to claim 1, since the laminated body 3 in which a large number of the metal foil 1 having a small thermal emissivity and the silica-based inorganic fiber sheet 2 are alternately laminated is emboss-pressed so as to undulate over the entire cross section, Due to the compressive deformation of the uneven portion of the emboss and the restoring elasticity of the metal foil, each layer is integrated without using a binder, and pressure resistance is also exerted by the compacting press.

According to the second aspect of the present invention, a single layer 6 made of an inorganic fiber sheet is provided on one surface of the laminate of the emboss-pressed metal foil 1 and the silica-based inorganic fiber sheet 2, specifically, the side facing the low temperature side. Since they are integrally laminated, the heat insulating effect of the laminate is effectively prevented against heat radiation from the high temperature side, and the heat conduction by the inorganic fiber sheet is effectively prevented at the low temperature side.

According to the third aspect of the present invention, a large number of minute through holes 1A are provided in the metal foil 1 to be laminated in a uniformly dispersed state.
This minute through hole 1A becomes a gas flow hole during vacuum exhaust,
Evacuation efficiency is improved.

[0014]

Embodiments of the present invention will be described below. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a sectional view showing a step of pressing the embodiment of FIG. 1, FIG. 3 is a sectional view of an embodiment of another invention, and FIG. 3 is a further embodiment of the invention. FIG. 4 is a cross-sectional view of the example, and FIG. 4 is a cross-sectional view showing a state in which the heat insulating wall of the vacuum heat insulating body is filled.

Example 1 An aluminum foil having a thickness of 10 μ was used as the metal foil 1, and a silica-based inorganic fiber sheet 2 had a thickness of 0.1 μm.
Using a glass wool sheet made of 5 mm class E glass fiber (fiber diameter 9 μm), 29 aluminum foils 1 and 30 glass wool sheets 2 are laminated alternately and laminated with a thickness of 15.2 mm without pressure. Body 3 was created. Next, as shown in FIG. 2, the laminated body 3 has an uneven pitch P = 2 mm and an uneven difference d = 1 mm.
The laminate 3 was compressed with a press 4 having embossing until the thickness of the laminated body 3 became 7 mm to obtain a filling material 5 for a vacuum heat insulating body.

Example 2 Using the same metal foil 1 and silica-based inorganic fiber sheet 2 as in Example 1, 10 aluminum foils 1 and 11 glass wool sheets 2 were laminated alternately as in Example 1. After performing compression by the same press as in Example 1 and performing embossing press, a rock wool board 6 compacted to a density capable of withstanding the atmospheric pressure in advance is further laminated on one side to obtain a filler 5 as shown in FIG. It was

[Examples 3 and 4] As the metal foil 1, FIG.
As shown in the enlarged view of FIG. 1, the vacuum heat insulator is filled in the same manner as in Example 1 and Example 2 except that 0.5 mm micro through-holes 1A ... 1A are provided in 1 cm ² in a uniformly dispersed state. Material 5 was obtained.

Comparative Example 1 The same metal foil 1 and silica-based inorganic fiber sheet 2 as in Example 1 were used, and 10 parts by weight of phenol resin (large) was used as a binder in the glass wool sheet 2 for 100 parts by weight of the glass wool sheet. A product name “Bryofen” manufactured by Nippon Ink Chemical Co., Ltd.) was sprayed and impregnated and laminated. Immediately thereafter, the metal foil 1 and the silica-based inorganic fiber sheet 2 were alternately laminated, consolidated by a flat plate press, and the binder was cured to obtain a compacted and integrated filler for a vacuum heat insulator.

The fillers obtained in Examples 1 to 4 and Comparative Example 1 were compared in handling property when carried and workability when inserted in a vacuum heat insulator, but there was almost no difference between them.

Next, after the filling material of the vacuum heat insulating materials of Examples 1 to 4 and Comparative Example 1 is filled in the heat insulating wall and the heat insulating wall is put in the heating furnace, the processing time until complete evacuation is completed. Was measured about 30 minutes when the filler 5 of Examples 1 and 2 was used, and about 30 minutes when the filler 5 of Examples 3 and 4 was used.
While all the work was completed in 20 minutes, in the case of Comparative Example 1, it took 1 hour to remove the gasification of the binder and complete the vacuum evacuation. As a result, it was confirmed that the use of the filler 1 for the vacuum heat insulator of the present invention required about half the processing time as compared with the comparative example.

Furthermore, when the pressure resistance test and the thermal conductivity of the vacuum heat insulators obtained in Examples 1 to 4 and Comparative Example 1 were measured, the results of the pressure resistance test of the vacuum heat insulators were as follows:
The heat transfer coefficient was 0.0035 or less, which was comparable to both.

[0022]

According to the first aspect of the present invention, the laminate serving as a filling material for the vacuum heat insulating body is consolidated and integrated by an embossing press without using a binder to a density capable of withstanding the atmospheric pressure against vacuum. For this reason, the process is shorter than the integration with the binder, and the handling and workability are equivalent to those of the integration with the binder.

The invention according to claim 2 has the same effect as that of the above invention, and has one side being a laminated body made of a metal foil with less heat radiation, and the other side being an inorganic fiber sheet with less heat conductivity. By using a laminated body on the high temperature side, a filler having an excellent heat insulating effect can be obtained.

According to the third aspect of the present invention, since the fine through holes are provided in the metal foil forming the laminated body in a uniformly dispersed manner, air circulation holes are secured at the time of vacuum exhaust, and the efficiency of vacuum exhaust processing is improved. Have.

[Brief description of drawings]

FIG. 1 is a sectional view showing a laminated body in the production of an embodiment of the invention of claim 1.

FIG. 2 is a sectional view showing a pressing step in the manufacture of the embodiment of the invention of claim 1;

FIG. 3 is a sectional view of an embodiment of the invention of claim 2;

FIG. 4 is an enlarged sectional view of an essential part of an embodiment of the invention of claim 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Metal foil with small thermal emissivity 1A ... Micro through-holes 2 ... Silica-based inorganic fiber sheet 3 ... Laminated body 4 ... Embossing press 5 ... Vacuum heat insulator filler 6 ... Single layer consisting of inorganic fiber sheet

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masahisa Ochi 2-26 Ohama-cho, Amagasaki-shi, Hyogo Stock company Kubota Mukogawa Works

Claims (3)

[Claims] 1. A density in which a large number of metal foils 1 having a small thermal emissivity and a plurality of silica-based inorganic fiber sheets 2 are alternately laminated, and the laminate 3 is corrugated over the entire cross section and withstands atmospheric pressure against vacuum. A filling material for a vacuum heat insulator, which is characterized by being embossed and integrated so as to be consolidated. 2. A density in which a large number of metal foils 1 having a low thermal emissivity and a plurality of silica-based inorganic fiber sheets 2 are alternately laminated, and the laminate 3 is wavy over the entire cross section and withstands atmospheric pressure against vacuum. Vacuum heat insulation, characterized in that a layer 5 that has been embossed so as to be consolidated up to and a single layer 6 made of an inorganic fiber sheet that is also consolidated up to a density that can withstand atmospheric pressure against vacuum are integrally laminated. Body filling material. 3. The filling material for a vacuum heat insulator according to claim 1 or 2, wherein a large number of minute through holes 1A are provided in a uniform distribution in a metal foil 1 having a small thermal emissivity. Filler for vacuum insulation.