JPH06123550A - Pack of vacuum insulation material - Google Patents

Abstract

PURPOSE:To improve thermal insulating characteristics by constituting a pack from a core material obtained from rigid urethane foam of continuous bubble structure prepared by expansion molding by means of a double conveyor wherein differences are provided in moving velocities between an upper conveyor and a lower conveyor and removing a skin layer therefrom, a container covering the core material, and adsorbents. CONSTITUTION:A pack is composed of a core material 8 having continuous bubble structure, a container 5, and adsorbents 9. Rigid urethane foam having continuous bubble structure prepared by means of a double conveyor 13 is carried by a lower conveyor 12, while it rises upwards, and the foam is pressed by upper conveyors 11 having different moving velocity from that of the conveyor 12, so that the foam is subjected to shearing forces, whereby a bubble structure oriented in the same direction as the advancing direction of the conveyor is obtained. As a result, by forming the core material 8 from rigid urethane foam having been cut, degree of orientation of cell is enhanced and thermal insulating characteristics can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum heat insulating material pack which can be used as a heat insulating material for refrigerators and the like.

[0002]

2. Description of the Related Art In recent years, in order to improve the heat insulating performance of a heat insulating box, attention has been paid to the use of a vacuum heat insulating material pack whose inside pressure is reduced. As the core material of this vacuum heat insulating material pack, powder such as pearlite, honeycomb, and foam are used.

For example, it has been proposed to use a hard urethane foam having an open cell structure as a core material, as disclosed in Japanese Patent Laid-Open No. 14725/1987.

The contents described in Japanese Patent Laid-Open No. 62-14725 will be described with reference to FIGS. 4 and 5. In the figure, reference numeral 1 is a hard urethane foam block which is foamed and cured in an open panel jig 2 using a urethane high-pressure foaming machine. Three
Is a high-density skin layer having closed cells formed on the surface of the hard urethane foam block 1, and the skin layer 3
Is removed from the hard urethane foam block 1 and cut into a predetermined size to obtain a core material 4 having a complete open cell structure.

The core material 4 thus obtained is covered with a container 5 made of a metal-plastic laminate film to hermetically seal the inside under reduced pressure. As a result, the vacuum heat insulating material pack 6 having no problem that the heat insulating performance is deteriorated can be obtained.

[0006]

However, in the above-mentioned prior art, the skin layer having a large number of closed cells formed on the surface of the hard urethane foam block is removed in order to obtain a heat insulator having a completely open cell structure. Therefore, there is a problem that the product yield is deteriorated and it cannot be manufactured industrially at low cost.

In order to improve such deterioration of product yield, it was considered to increase the block size of the hard urethane foam block to reduce the proportion of the skin layer to be removed and improve the product yield.

However, in the case of jig foaming, when the block size is increased, the raw material is discharged for a long time, and there is a large time lag between the raw material in the early stage of discharge and the raw material in the latter stage of discharge. There is a problem that a raw material having the above formula forms a block while being mixed, and as a result, a desired heat insulating performance cannot be obtained due to an abnormal orientation of the cell, and when it is vacuum-sealed, it shrinks.

A method for manufacturing a double conveyor, which is generally used as a method for manufacturing a soft slab, such as a continuous urethane soft block manufacturing line U manufactured by Maruka Kakoki Co., Ltd.
If the BT type is applied, the above problems such as jig foaming are solved, and it becomes possible to continuously produce large-sized foam blocks. However, the open-cell structure produced by the double conveyor is used. The rigid urethane foam has a desired movement since it moves in the traveling direction of the conveyor while rising, and is pressed by the upper conveyor, so that the orientation ratio of the cell becomes small and, as a result, the cell diameter in the heat insulating direction becomes large. There was a problem that the heat insulation performance could not be obtained.

[0010]

In order to solve the above-mentioned conventional problems, the vacuum heat insulating material pack of the present invention is foam-molded by a double conveyor having a difference in the moving speed of the upper and lower conveyors, and the skin layer is removed. A core material obtained from a rigid urethane foam having an open-cell structure, a container covering the core material, and an adsorbent are sealed under reduced pressure.

The method of manufacturing a vacuum heat insulating material pack according to the present invention comprises:
Foam molding a hard urethane foam with an open-cell structure by a double conveyor with a difference in the moving speed of the upper and lower conveyors, remove the skin layer and put the core material cut into a predetermined size in a container with an adsorbent, It is manufactured by vacuum-sealing the inside.

Furthermore, the vacuum heat insulating material pack of the present invention is
In the upper and lower conveyors of the double conveyor with a difference in the moving speed, foam molding was performed with a difference in the height interval between the upper and lower conveyors that were formed, and obtained from the rigid urethane foam with an open-cell structure with the skin layer removed. A core material, a container covering the core material, and an adsorbent, and the inside is vacuum-sealed.

In the method of manufacturing the vacuum heat insulating material pack in this case, a rigid urethane foam having an open-cell structure is provided with a difference in the moving speed of the upper and lower conveyors, and the height interval between the upper and lower conveyors formed is also different. The core material is foam-molded by the double conveyor provided, the skin layer is removed, and the core material cut into a predetermined size is put into a container together with an adsorbent, and the inside is vacuum-sealed.

[0014]

With the above structure, the hard urethane foam having an open-cell structure manufactured by the double conveyor moves on the lower conveyor while rising, and is pressed by the upper conveyor having a different moving speed. As a result, the foam is subjected to a shearing force to obtain a cell structure oriented in the same direction as the traveling direction of the conveyor. As a result, by using the cut hard urethane foam as the core material, a foam having a high cell orientation rate is used, and as a result, a vacuum heat insulating material pack having excellent heat insulating performance can be obtained. You can do it.

Further, by forming the double conveyors with different height intervals and performing foam molding, a stronger compressive / shearing force is applied, and the density is made uniform, so that variations in heat insulating performance can be reduced.

As a result, it becomes possible to continuously produce a large-sized hard urethane foam having an open cell structure, the product yield is remarkably improved, and a core material having excellent performance and uniform quality is manufactured industrially at low cost. It becomes possible to do it.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be explained. In the figure, 7 is a vacuum heat insulating material pack, which is composed of a core material 8 having an open-cell structure, a container 5, and an adsorbent 9.

10 is an upper conveyor 11 and a lower conveyor 12
Is a large block hard urethane foam having an open cell structure obtained by the double conveyor 13 consisting of, and 14 is a block obtained by removing the skin layer of the foam block of 7.

Large block rigid urethane foam 10
In manufacturing the above, first, the urethane raw material 16 is discharged from the head 15 of the foaming machine (not shown) onto the release paper 17 laid on the lower conveyor 12. The foam 18 that has started foaming is placed on the release paper 17 laid on the conveyor 12 and moves.

Then, by the time of gelation, the upper conveyor 11
While moving further, the front upper conveyor 19 of the upper conveyor 11 has a higher moving speed than the lower conveyor 12 and is provided with an inclination so that the height interval between the inlet portion 20 and the outlet portion 21 is narrowed. Therefore, the foam is on the front upper conveyor 19
While being pushed by and moving forward while receiving shearing force in the forward state. Next, it moves from the front upper conveyor 19 to the lower conveyor 12 and the rear upper conveyor 22 at a constant speed, and is sandwiched and moved to the double conveyor 13 until curing, taken out, and the molding is completed. The block 14 from which the skin layer has been removed from the obtained large block hard urethane foam 10 is cut in the conveyor flow direction to obtain the core material 8.

The cell orientation ratio of the core material 8 thus obtained,
The results of measuring the density and the thermal conductivity of the vacuum heat insulating material pack 7 which is covered with the core material 8 and hermetically sealed under reduced pressure are shown in (Table 1).

[0022]

[Table 1]

Similarly, when the moving speed of the front upper conveyor 19 is the same as that of the lower conveyor 12 and the inlet portion 20 and the outlet portion 21 are at the same height, the cell orientation ratio and density of the core material 8, The results of measuring the thermal conductivity of the vacuum heat insulating material pack 7 are shown in Table 1 as a comparative example.

As is clear from Table 1, when the moving speed of the front upper conveyor 19 is made higher than that of the lower conveyor 12 and the moving speeds of the upper and lower conveyors are made different from each other, the front upper conveyor 19 is inclined. It can be seen that there is less variation and more excellent heat insulation performance is exhibited.

This is because the core material 8 described above has a higher orientation rate than that of the comparative example and a uniform density, so that the contribution of heat conduction by the resin and the contribution of radiation are stably reduced. I think.

Therefore, the moving speed of the front upper conveyor 19 is set to be higher than that of the lower conveyor 12, and the front upper conveyor 19 is moved.
By using a core material 8 having a uniform density and having a gradient, the core orientation 8 is forcibly increased, it is possible to obtain a vacuum heat insulating material pack 7 having excellent heat insulating performance with little variation.

[0027]

As described above, the vacuum heat insulating material pack of the present invention is formed from a rigid urethane foam having an open-cell structure in which the skin layer is removed by foam molding with a double conveyor having a difference in the moving speed of the upper and lower conveyors. The obtained core material, a container covering the core material, and an adsorbent are sealed under reduced pressure, so that the cell orientation of the core material becomes large and a vacuum heat insulating material pack having excellent heat insulation performance is obtained. be able to. Further, by forming the double conveyors with different height intervals and performing foam molding, a stronger compression / shear force is received, and the heat insulation performance can be stabilized by making the density uniform.

As a result, it becomes possible to continuously produce a large-sized rigid urethane foam having an open cell structure, the product yield is remarkably improved, and the core material having excellent performance and uniform quality is industrially inexpensive. Can be manufactured in. Since it becomes possible to industrially manufacture a core material having excellent performance at low cost, it is possible to provide a vacuum heat insulating material pack that can contribute to energy saving at low cost.

[Brief description of drawings]

FIG. 1 is a sectional view of a vacuum heat insulating material pack according to an embodiment of the present invention.

FIG. 2 shows a hard urethane foam according to an embodiment of the present invention.
Enlarged sectional view showing the manufacturing process of the mu-block

FIG. 3 shows a hard urethane foam according to an embodiment of the present invention.
Perspective view of the mobile block

FIG. 4 is a sectional view of a conventional vacuum insulation material pack.

FIG. 5 is a manufacturing diagram of a conventional rigid urethane foam block.

[Explanation of symbols]

 5 Container 7 Vacuum insulation material pack 8 Core material 9 Adsorbent 13 Double conveyor

Claims (4)

[Claims] 1. A core material obtained from a rigid urethane foam having an open-cell structure, which is foam-molded by a double conveyor in which the moving speeds of the upper and lower conveyors are provided and the skin layer is removed,
A vacuum heat insulating material pack comprising a container for covering the core material and an adsorbent, the inside of which is hermetically sealed under reduced pressure. 2. A core material obtained by foam-molding a rigid urethane foam having an open-cell structure by a double conveyor having a difference in the moving speed of the upper and lower conveyors, removing the skin layer and cutting it into a predetermined size. A method for manufacturing a vacuum heat insulating material pack, which is placed in a container together with the inside of the container and is vacuum-sealed. 3. In the upper and lower conveyors of the double conveyor having different moving speeds according to claim 1, foam molding is performed by providing a difference in height interval between the upper and lower conveyors to be formed,
Rigid urethane foam with open cell structure without skin layer
A vacuum heat insulating material pack comprising a core material obtained from a rubber, a container covering the core material, and an adsorbent, the inside of which is hermetically sealed under reduced pressure. 4. A skin layer is formed by foaming a rigid urethane foam having an open-cell structure with a double conveyor having a difference in the moving speed of the upper and lower conveyors and a difference in the height interval between the upper and lower conveyors formed. A method for manufacturing a vacuum heat insulating material pack, in which a core material that has been removed and cut into a predetermined size is placed in a container together with an adsorbent and the inside is vacuum-sealed.