JPH07158791A - Manufacture of vacuum heat insulated structure - Google Patents

Abstract

PURPOSE:To dispense with a vacuum chamber and manufacture a large-sized vacuum heat insulated structure without being limited by the size by housing a space holding member in the facing body having an opening part and an exhaust tube, and then vacuum exhausting the inner part of the facing body. CONSTITUTION:A heat insulating core material is filled as a space holding member 5 in the inner part of a facing body 4 forming an airtight chamber 3 therein, and the airtight chamber 3 is vacuum exhausted, whereby a vacuum heat insulated structure 1 is manufactured. In the facing body 4, an opening part 4a capable of inserting the space holding member 5 into the airtight chamber 3 and an exhaust tube 2 movably installed to the insert part of the facing body 4 to exhaust the air from the airtight chamber 3 are arranged. In the manufacture, the space holding member 5 is first housed into the airtight chamber 3 through the opening part 4a, and the opening part 4a is then sealed. The airtight chamber 3 is vacuum exhausted through the exhaust tube 2, and the exhaust tube 2 is then sealed. Thus, no vacuum chamber is required, and a large-sized vacuum heat insulated structure 1 can be easily manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is particularly suitable for forming a heat insulating wall, so that a cold storage, a cold container, a cold box,
The present invention also relates to a method for manufacturing a vacuum heat insulating structure used in a domestic electric refrigerator, etc., and more specifically, a heat insulating core material as a space holding material is filled in an outer body that forms an airtight chamber therein, The present invention relates to a method for manufacturing a vacuum heat insulating structure obtained by evacuating a closed chamber.

[0002]

2. Description of the Related Art Conventionally, when manufacturing such a vacuum heat insulating structure, a space retaining material is housed in an outer casing,
These were housed in a vacuum chamber, the interior of the exterior body was evacuated in the vacuum chamber, and the opening of the exterior body was heat-sealed to manufacture.

[0003]

Therefore, the obtained vacuum heat insulating structure is limited to a relatively small size due to the limitation of the size of equipment such as the vacuum chamber and the heat seal device. Therefore, when it is not possible to manufacture a large-sized vacuum heat insulating structure, and when attempting to manufacture a large-area panel heat insulating part for a household electric refrigerator, etc., a vacuum heat insulating structure having a relatively small area is used for one panel of multiple panels. The panel heat insulating part has been manufactured by adhering it to the wall with an adhesive or holding it with tape or the like, and injecting polyurethane foam between the other wall and the vacuum heat insulating structure. As a result, the bonding process takes a long time and causes a cost increase, and since the size of the vacuum heat insulating structure is small, joints between the panels are increased and heat loss is large. Further, in the conventional manufacturing method, the following problems may occur during the vacuum evacuation operation. Since the air in the powder escapes during exhaust, irregularities are likely to occur on the surface.
When the exhaust speed is increased in order to shorten the exhaust time, air is suddenly released, so that cracks are likely to occur on the panel surface. Also, the exhaust speed at the upper and lower surfaces of the space holding material is likely to be different,
Problems such as warpage are likely to occur. Therefore, in order to adjust the speed of the exhaust operation and prevent the occurrence of warpage, etc., it is necessary to install a device for making a work on these in the vacuum chamber, and even if it is installed, it is operated under vacuum,
There was a limit to fine operations such as fine adjustment of the position of the seal.
Furthermore, when the vacuum chamber is configured to have the minimum function capable of performing such fine adjustment, the equipment cost becomes very high. In addition, since the work is performed in a vacuum chamber, it is difficult to make fine adjustments during evacuation, and the position of the seal portion must be adjusted until heat sealing is completed after evacuation.
There is a problem that it is not possible to strictly check the sealing accuracy, the surface accuracy of the panel, the warp, and the like.

An object of the present invention is to manufacture a large-sized vacuum heat insulating structure which has never been available before. Even when it is used for a large panel portion, the work can be performed easily and quickly and the heat insulating effect is high. It is possible to obtain a vacuum heat insulating structure, properly grasp various problems that tend to occur during exhaust operation appropriately, and it is easy to perform work to obtain a highly accurate product, and a vacuum heat insulating structure with good yield can be obtained. To obtain a manufacturing method.

[0005]

Means for Solving the Problem A characteristic means of a method for manufacturing a vacuum heat insulating structure according to the present invention for achieving this object is that an opening for inserting a space holding material into an airtight chamber as an exterior body is provided. Use an exterior body with an exhaust tube that is capable of exhausting gas from an airtight chamber and that is equipped with an exhaust tube that is movably mounted in the insertion direction at the insertion site with respect to the exterior body, and use a space holding material through an opening. A first step of sealing the opening portion after housing in the airtight chamber, and a second step of performing a vacuum operation in the airtight chamber from the exhaust tube after the first step and then sealing the exhaust tube. In some cases, the actions and effects are as follows.

[0006]

The exterior body of the present application is constituted by including the opening and the exhaust tube, and the space holding material is housed in the exterior body. Here, as the space holding material, a powdery or fibrous material having a heat insulating property contained in an air permeable inner bag, or an open cell foam having a regular shape is used. Then, in the production of the vacuum heat insulating structure, the space retaining material is housed in the exterior body and the opening is sealed in the first step under normal atmospheric pressure. In this state, the inside of the exterior body is under atmospheric pressure. Then, in the second step, the airtight chamber formed inside the exterior body is evacuated through the exhaust tube. This operation is not an operation in a vacuum chamber but an operation under normal atmospheric pressure. Therefore, for example, when a warpage such as a crack is generated, it can be accurately captured and appropriately worked from the outside. Then, after the airtight chamber reaches a predetermined state, the exhaust operation is ended and the exhaust tube portion is sealed. Now,
The exhaust tube is configured to be movable at a portion where it is inserted into the exterior body.This is because the tip of the exhaust tube is positioned near or inside the holding material in the state where the space holding material is stored, This structure eliminates the formation of a region where the front and back surfaces of the exterior body are in close contact with each other between the exhaust tube and the space holding member during the exhaust operation, and allows the exhaust operation to proceed efficiently.

[0007]

According to the present invention, therefore, when manufacturing a vacuum heat insulating structure, a vacuum chamber is not used, and desired work is performed from the outside of the exterior body during vacuum evacuation operation (second step) according to the manufacturing conditions. As a result, it has become possible to manufacture high quality and relatively large product sizes as in the past. Therefore, it is possible to obtain a vacuum heat insulating structure that can perform the work easily and quickly even when it is used for a large-sized panel portion and has a high heat insulating effect. As a result, manufacturing equipment is inexpensive, and problems such as displacement of the seal portion, defective panel accuracy, surface accuracy, warpage, etc. that tend to occur during manufacturing are solved, and a highly accurate and very inexpensive vacuum insulation structure is provided. It has become possible to carry out manufacturing. Therefore, there was almost no loss at the time of manufacturing, and it was possible to establish a very preferable manufacturing method as a mass production method.

[0008]

Embodiments of the present application will be described with reference to the drawings. 1 is a perspective view of the vacuum heat insulating structure 1 of the present application, and FIG.
Details of the vicinity of the exhaust tube 2 provided in the vacuum heat insulating structure 1 are shown. In this vacuum heat insulating structure 1, an exterior body 4 forming an airtight chamber 3 therein is filled with a heat insulating core material as a space holding material 5, and the airtight chamber 3 is evacuated. It is a bag-shaped plastic film such as polyester and polypropylene that has been subjected to aluminum lamination. Further, the space retaining material 5 is a powder or fibrous material 6 such as silica or pearlite.
Is stored in an inner bag 7 made of kraft paper, non-woven fabric or the like and molded into a plate shape.

The exterior body 4 is constructed by stacking at least a pair of upper and lower sheets 40 and having a space inside which serves as the airtight chamber 3, and the space holding member 5 is provided on one side thereof. The airtight chamber 3 is provided with an opening 4a that can be inserted, and a pair of exhaust tubes 2 is provided at a position different from the opening 4a. By using the exhaust tube 2, the gas can be exhausted from the airtight chamber 3. Explaining the exhaust tube 2 further, as shown in FIG. 2, the exhaust tube 2 is in an airtight state with respect to the exhaust tube insertion holding member 41 that is sandwiched and fixed to the pair of sheets 40 forming the exterior body 4. Is slidable. Therefore, the exhaust tube 2 is movable in the insertion direction of the exterior body 4 at the insertion site A. Further, the exhaust tube 2 is configured such that the exhaust tube tip portion 20 arranged on the airtight chamber 3 side is provided with a filter 21 capable of preventing the intrusion of powder or fibrous substances, and can be pierced into the inner bag 7. It is configured as a tubular member.

The specific structure of the vacuum heat insulating structure 1 will be described below. Vacuum insulation structure 1 Exterior 4 size 1m × 2m square material Plastic laminate film Opening 4a Formed on one side of short side Exhaust tube 2 installed 2 places Tube diameter 3mm Space holding material 5 size 800 × 1600mm × 15mmt Contents Craft What contains perlite powder in a bag and is molded and dried Now, the manufacturing process of the vacuum heat insulating structure 1 will be described below in the order of steps. First Step After the space holding material 5 is housed in the airtight chamber 3 through the opening 4a, the opening 4a is sealed (implemented under atmospheric pressure). Second step After the airtight chamber 3 is evacuated from the exhaust tube 2, the exhaust tube 2 is sealed (implemented under atmospheric pressure). Here, during vacuum evacuation operation, the vacuum heat insulating structure 1 is pressed from above and below to suppress warpage and the like. Further, at this time, the surface accuracy of the space retaining material 5 is confirmed, the occurrence of cracks on the panel surface is confirmed, the warp is confirmed, and the seal portion 4 is formed.
While confirming the position seal accuracy in step 2, proceed with the work while sequentially performing correction work. On the other hand, when the space holding material 5 in which the powder is stored in the inner bag 7 is used as in this embodiment, the exhaust tube 2 is pierced into the inner bag 7 in this step to perform vacuum exhaust operation.

The characteristics of the obtained product will be described below. Thermal insulation properties of the product Panel thermal conductivity 0.0058 kcal / mh ° C (Measurement conditions, one side of the vacuum insulation structure was set to -50 ° C, the other side was set to 23 ° C. , The thermal conductivity of the panel is calculated) Further, when the appearance is inspected, the position of the seal portion 42,
There were no problems with panel accuracy, surface accuracy, or warpage, and there were no defective products. Furthermore, of course, the vacuum heat insulating structure 1 manufactured here has a large size which has been impossible in the past. Conventional size is max50
It is 0 × 500 mm.

[Other Embodiments] In the above embodiment, the space-maintaining material 5 is mainly formed of a molded body containing powder in the inner bag 7.
However, this may be a calcium silicate molded body, an open-cell foam molded body of polyurethane, phenol, or the like. In this case, the exhaust tube 2
Does not need to be pierced into the space holding material 5, and if the tip of the exhaust tube is brought as close as possible to the space holding material and the exhaust work is advanced, good exhaust work can be performed.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a perspective view of a vacuum heat insulating structure.

FIG. 2 is a diagram showing a configuration of a proximal end portion of an exhaust tube.

[Explanation of symbols]

 1 Vacuum Insulation Structure 2 Exhaust Tube 3 Airtight Chamber 4 Exterior 4a Opening 5 Space Holding Material 6 Powder 7 Inner Bag 20 Exhaust Tube Tip 21 Filter

Claims (3)

[Claims] 1. A heat-insulating core material as a space retaining material (5) is filled in an exterior body (4) which forms an airtight chamber (3) therein, and the airtight chamber (3) is evacuated. A method of manufacturing a vacuum heat insulating structure (1), comprising: an opening (4a) into which the space retaining material (5) can be inserted into the airtight chamber (3), and the airtight chamber as the exterior body (4). Gas can be exhausted from (3) and the insertion part (A) into the exterior body (4)
In the above, an exterior body with an exhaust tube provided with an exhaust tube (2) movably mounted in the insertion direction is used, and the space retaining material (5) is provided in the opening (4).
The first step of sealing the opening portion (4a) after storing it in the airtight chamber (3) via a), and the airtight chamber (2) from the exhaust tube (2) after the first step. 3) A method for manufacturing a vacuum heat insulating structure, which comprises a second step of sealing the exhaust tube (2) after evacuating the inside. 2. The space retaining material (5) contains a powdery material (6) or a fibrous material having a heat insulating property in a breathable inner bag (7), and the exhaust tube (2) is Exhaust tube tip portion (2) arranged on the side of the airtight chamber (3)
0) is a tubular member configured to be able to pierce the inner bag (7) with a filter (21) capable of blocking the intrusion of the powdery or fibrous material, and after the first step, The method for manufacturing a vacuum heat insulating structure according to claim 1, wherein in the second step, the exhaust tube (2) is pierced into the inner bag (7) to perform vacuum exhaust operation. 3. The method for manufacturing a vacuum heat insulating structure according to claim 1, wherein the space retaining material (5) is an open-cell foam having a fixed shape.