JPS6344528B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a heat insulating box body in which a part that acts as a flow path resistance of a foam heat insulating material during the growth process of the heat insulating material is attached to the wall surface of one of the inner and outer boxes. The purpose is to promote the growth of foam insulation in the part-side area of the space.

In general, in an insulating box body in which foam insulation material is filled between the inner and outer boxes, for example, parts such as reinforcement or refrigeration are attached to the outer surface of the inner box, that is, the side of the insulation material, and foaming stock solution is injected into the space formed between the two boxes. , as the parts act as flow path resistance for the foamed insulation material during the growing process, the insulation material on the component side of the space grows slower than the insulation material on the other side of the space, making it difficult for air to escape, and as a result, the inside of the insulation material The generated air bubbles cannot be completely removed, and residual air is formed as an air pocket (referred to as a void) between the heat insulating material and the wall surface of, for example, an outer box, which faces the wall surface on which the component is attached. This air pocket gradually contracts due to the temperature drop after foaming, for example, the temperature drop until the insulation material returns to room temperature immediately after foaming, or the temperature drop that occurs during operation of the refrigeration cycle, resulting in a small volume and negative pressure, and the outer box wall surface was attracted to the insulation material side and partially deformed, which not only damaged the product value but also reduced the insulation effect of the foam insulation material. This drawback was most apparent in vacuum-formed inner or outer boxes that had roughened sides made of heat-insulating materials such as fluorocarbon-resistant ABS resin.

The present invention has been made based on these drawbacks.

Examples of the present invention will be described below with reference to the drawings.
1 shown in Fig. 1 is an insulated box body such as a storage warehouse, which is composed of a storage section A with an opening for storing and taking out products on the top surface, and a mechanical section B in which a compressor, condenser, etc. (not shown) are installed. As shown in Fig. 2, the storage section has an inner box 2 made of metal, an outer box 3 with a wide mouth made of metal or a synthetic resin resistant to chlorofluorocarbons such as ABS, and the upper ends of both the inner and outer boxes are connected. The outer surface of the inner box 2, that is, the side surface of the insulation material The inside of the refrigerator 8 is cooled by a meandering cooler 7 which is arranged in a plurality of branches. Reference numeral 9 denotes a refrigeration component such as a header for collecting the refrigerant returned from the cooler, which is attached to one side wall surface 2a of the inner box and buried in the foam insulation material 6 together with the cooler.

Next, a method of manufacturing the storage section A having such a structure will be explained with reference to FIG.

An inner box 2 has a cooler 7 attached to an outer circumferential wall in advance, a component 9 is attached to one side wall surface 2a of the circumferential wall, and a foamed heat insulating material 6 is growing on a wall surface 3a opposite to the wall surface 2a on which the component is attached. After connecting the outer box 3 coated with a surface treatment agent 10 to make it slippery with a decorative frame 4 so as to form a space 5, a heated male jig 11 is first used so that the decorative frame 4 faces downward. After the inner box 2 is fixed, a foaming stock solution is injected into the space 5 through injection holes 13 at both ends of the bottom wall of the outer box 3. After injection, the injection hole 13 is closed with a plug 15 and the outer box 3 is closed with a heated female jig 12.
to be fixed. In addition, for injection of the stock solution, insert the outer box 3 into the female jig 1.
It may be done after fixing in step 2. The foaming solution injected into the space 5 gradually foams and grows due to chemical changes, and the air and fluorocarbon gas in the space 5 are pushed out from the plurality of small holes 14 in the center of the bottom wall of the outer box 3 as shown by the arrows. As a result, the space 5 is filled with foam and solidified to form the foam heat insulating material 6, completing the production of the storage section A.

During the foaming process, the component 9 acts as a flow path resistance for the growing foamed heat insulating material 6, but due to the surface treatment agent 10 formed on the wall surface 3a of the outer box 3, the heat insulating material in the component side area of the space 5 is reduced by the surface treatment agent 10. The insulation material on the other side grows at approximately the same rate as the insulation material on the other side. Therefore, space 5
The state of air discharge from the component side area is also good, and no air pockets, so-called voids, are formed between the wall surface 3a and the foamed heat insulating material 6. It should be noted that since the wall surface 3a is coated with the surface treatment agent 10 and does not adhere to the foamed heat insulating material 6, warping due to shrinkage of this heat insulating material does not occur.

FIG. 3 shows another embodiment of the present invention, in which a wall surface 3a
By attaching a plate 16, such as a metal plate, which has a surface on which the growing foamed heat insulating material 6 can easily slip, to the wall surface 3a, the growth rate of the heat insulating material in the component side area of the space 5 can be accelerated. The plate itself can also be used as a reinforcing plate for the wall surface 3a. Incidentally, the same effect can be obtained when a sheet 17 having a surface on which the foamed heat insulating material 6 is more slippery than the wall surface 3a is attached as shown in FIG. 4. Further, the present invention produces similar effects even when the parts 9 are attached to the outer box 3 and the inner box 2 is subjected to surface treatment.

As described above, in the present invention, during the growth process of the foam insulation material, a component that acts as a flow path resistance of the insulation material is attached to one wall surface of both the inner and outer boxes, and the foam insulation material that is being grown is attached to the wall surface opposite to this wall surface. Either apply a surface treatment to make the material slippery, or provide a plate or sheet material that makes the side of the insulation material more slippery than the wall surface, and then inject the foaming solution into the space between the inner and outer boxes and allow the foam to solidify. Because it is made by manufacturing an insulated box,
To speed up the growth of a heat insulating material in a part-side area of a space, to achieve good air exhaust conditions, to equalize the growth of the foamed heat insulating material, and to prevent the generation of air pockets that impair product value and reduce the heat insulating effect. Can be done.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, with FIG. 1 being a perspective view of a heat insulating box, and FIG. 2 being a longitudinal sectional view showing the foaming process.
3 and 4 are longitudinal sectional views of main parts showing other embodiments of the present invention. 2...Inner box, 3...Outer box, 6...Foam insulation material,
9... Parts, 10... Surface treatment agent, 16... Plate, 17... Sheet material.

Claims (1)

[Claims] 1. During the growth process of the foam insulation material, a component that acts as a flow path resistance for this insulation material is attached to one wall of both the inner and outer boxes, and the growing foam insulation material is placed on the opposite wall to prevent it from slipping. Thermal insulation is obtained by subjecting the surface to a surface treatment such as Method of manufacturing the box.