JPH026434B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for manufacturing a heat insulating box for a refrigerator, a low-temperature case, etc.

(b) Prior art Japanese Patent Publication No. 47-4233 (JPC, 70A221.2) discloses a method for forming a heat insulating layer by foaming in a gap formed between double walls, in which the foamed part of the foamed heat insulating material is made flexible. A method for forming a heat insulating layer is disclosed in which the heat insulating material is foamed after inserting a heat insulating material for adjustment that exhibits properties of at least one of air permeability and air permeability.
According to this method, when the amount of raw materials or injection amount is slightly small, there is a regulating insulation material, so no cavities are created, and when the amount of injection is larger than the above, the foamed excess of the raw material is absorbed by the regulating insulation material. This prevents the internal pressure from becoming excessive by compressing the adjusting insulation material, eliminating the need to inject extra raw materials and reducing waste. It is said to have the advantage that it not only prevents deformation of the lower parts, but also significantly reduces the strength and precision of the jig.

That is, in this method, a so-called honeycomb portion with insufficient foaming is intentionally formed in the foam concentration portion by utilizing the volume change of the adjusting heat insulating material.

However, in this method, the air in the void is removed from the injection port where the raw material for the foam insulation material is injected, so the injection port, which is the upstream area of the foam insulation material when viewed from the foam concentration area, is the final point of foaming, and the adjustment Even if a heat insulating material is used, the flow of the foamed heat insulating material to the foam condensation part is poor, resulting in poor foaming, that is, a honeycomb portion is formed around the adjusting heat insulating material, and the outer wall is deformed due to shrinkage and voids.

(c) Object of the Invention In addition to solving the drawbacks of the prior art, it is an object of the present invention to smoothly vent air from the exhaust hole and eliminate air pockets near the exhaust hole.

(d) Structure of the invention Both the inner and outer boxes are connected to form a space between the two boxes to be filled with foam insulation material, and during the foaming process, the undiluted solution of the foam insulation material is injected into the space from the injection hole of the outer box. In the method of manufacturing a heat insulating box body, the air in the space is discharged to the outside from an exhaust hole in a wall that is the upper surface of the outer box, and a foamed heat insulating material is foamed in the vicinity of the exhaust hole when viewed from the exhaust hole. A weir is disposed in the space that is an upstream area in the flow direction of the foam insulation material, and blocks a part of the space to obstruct the flow of the foam insulation material toward the exhaust hole, and by this weir, the foam insulation material By bypassing the material and guiding it to the exhaust hole, the part of the space that was upstream in the flow direction of the foam insulation material as seen from the exhaust hole is filled with foam insulation material before the area near the side of the weir exhaust hole. A method for manufacturing a heat insulating box that avoids foaming defects.

(E) Embodiments of the Invention Figures 4 to 6 show embodiments of the present invention. In the figures, 1 is an insulating box such as a low-temperature show case used for selling ice cream, etc. The main body is composed of a heat insulating box 4 equipped with a window 2 and two left and right transparent doors 3A, 3B on the front half of the top surface, which can be slid in the front and rear directions, a machine room 5 below the main body, and a machine room 5 above the second half of the top surface. A storage chamber 6 is formed.

The heat insulating box includes an inner box 8 made of metal with an open top that defines the interior 7 of the refrigerator, and an outer box made of metal with an open top that stores this inner box and forms a space between the inner box and the inner box. 9 and a foamed heat insulating material 10 such as hard polyurethane which is foamed and filled into the space between the inner and outer boxes, and has an opening 11 on one side for loading and unloading products.
and a projecting wall 12 extending in the opening direction. The inner box consists of front, back, left, right, and bottom walls 8A to 8E, and a main cooler 13 consisting of a meandering low-temperature refrigerant pipe provided on the outer peripheral surface thereof, and a main cooler 13 arranged in the rear half of the upper surface, A plate-shaped auxiliary cooler 14 formed by a so-called roll bonding method and serving as an inner wall of the projecting wall.
The interior 7 of the refrigerator is cooled by this. Further, the outer box has a front wall 9A, a back wall 9B, and both left and right walls 9C and 9D,
A bottom wall 9E that slopes gently upward to the rear and has an injection hole 16 for the foam insulation material on the rear edge and an appropriate number of exhaust holes 17 on the front edge, and a bottom wall 9E that is gently sloped upward and has an injection hole 16 for the foam insulation material on the rear edge and an appropriate number of exhaust holes 17 on the front edge; It consists of an upper wall 18 that slopes backwards downward and serves as an outer wall of the projecting wall. Further, inside the foamed heat insulating material 10, there is a prismatic weir 19A made of a heat insulating molded material such as foamed polystyrene and arranged near the exhaust hole 17.
, a cylindrical heat insulating block 19B, and a partition member 20 made of a heat insulating molded material such as expanded polystyrene are buried. The weir and block are arranged in both the inner and outer boxes 8 and 9 so that they are located behind the exhaust hole 17.
The partition member 20 is interposed between the auxiliary cooler 14 and the upper wall 18 in its longitudinal direction. Note that both the inner and outer boxes are connected to each other by breakers 21 and 22 made of resin.

The machine room 5 includes a lower part of the front wall 9A of the outer box, lower parts of both left and right walls 9C and 9D, a bottom wall 9E, an exhaust passage 23A opening vertically at the upper edge, and a lower part of the exhaust passage. Exhaust passage 23 that opens in the front-rear direction
A removable cover 24 that forms a part B and covers the rear opening, and a front wall 9A of the outer box that is located at the rear of the lower surface.
A refrigerant compressor 27, which forms a refrigeration cycle together with the main and auxiliary coolers, is connected to the base 26 and the base 26, which forms an intake passage 25 between the base 26 and the lower end.
6. A pair of supports 29A in which wire finch tube condensers 28 are provided on both front and rear edges of the intake passage;
They are each attached to 29B.

Next, manufacturing of the heat insulating box will be explained with reference to FIGS. 1 to 3.

First, glue the weir 19A and block 19B.
The inner box 8, which is attached to the outer surface of the bottom wall 8E, and the outer box 9 are connected by breakers 21 and 22, and the weir, block, and partition material 20 are interposed in the space 30, and the weir 19A is connected to the spacer. At the same time, a gap 31 is formed between the heat insulating block and the bottom wall 9E of the outer box 9, and an opening 11 and a projecting wall 1 are formed on one side.
Assemble the box 4' in which 2 was formed. Next, the opening 11
And after installing the box 4' with the projecting wall 12 as the top surface,
After inserting the nest 32 into the inner box 8 through the opening 11 and placing it on the front half of the bottom wall 8E, the nest 32 is slid backward and placed directly under the projecting wall 12 as shown in FIG. Due to this nested arrangement, the bottom wall 8E of the inner box 8
receives the weight of the nest 32 and swells and bends toward the space 30, but due to this bending, the insulation block 19B
hits the bottom wall 9E of the outer box 9, and the gap 31 is eliminated. After placing the nest, place the nest in the inner box 8.
While the box 4' is in the box, the box 4' is turned over so that the opening 11 and the projecting wall 12 are on the bottom side and the bottom wall 9E is on the top side, and the box 4' is held down with both the inner and outer jigs 33 and 34 as shown in FIG.
Due to the above-mentioned inversion, the weight of the nest 32 is applied to the auxiliary cooler 14, which is the inner wall of the projecting wall 12.
As a result, the bending of the bottom wall 8E of the inner box 8 is eliminated, and the insulation block 19 is removed from the bottom wall 8E of the outer box.
After separating from E, the gap 31 is formed again. In such a state, the foaming stock solution 10' is poured into the space 3 from the injection hole 16.
By injecting the foam into the foamed heat insulating material 10, the raw solution 10' foams and grows as shown by the arrow in FIG.
The above-mentioned insulation box 4 is obtained.

As the foamed insulation material grows, it grows into the space 30 between the bottom walls 8E and 9E, which is the final area of foaming, and when viewed from the exhaust hole 17, the foamed insulation material 10 reaches the upstream area in the flow direction (flow from the rear). The flow is obstructed by the weir 19A located in the opposite side of the river, and the flow is divided into left and right directions as shown by the dashed-dotted line arrows in Fig. 3.
It passes outside both ends of the weir 19A, and flows along the front wall 9A of the outer box 9, which is the upstream region in the flow direction of the foam insulation material 10 (with respect to the flow from the front) when viewed from the exhaust hole 17, and flows to both front walls 8A, 9A. It merges with the foamed heat insulating material 10 that has risen from the gap and heads toward the exhaust hole 17. That is, the foamed heat insulating material 10 loses its straightness due to the weir 19A, and ends up bypassing this weir and heading toward the exhaust hole 17. As a result, the front wall 9A, which was the upstream area of the exhaust hole 17, The foamed heat insulating material 10 is filled in the vicinity of the weir 19A before the vicinity of the side of the exhaust hole, and the exhaust hole 17 can be the final point of foaming.

Therefore, it is possible to prevent air pockets in the space 30, which is the upstream region of the exhaust hole 17, and to prevent foaming failure due to the air pockets.

Note that if the amount of foaming solution 10' injected into the foam insulation material 10 is slightly less than the predetermined amount, there is a possibility that a small amount of air bubbles may remain on the surface near the exhaust hole 17 of the weir 19A. Since the weir 19A acts as a reinforcing material, the bottom wall 9E is strengthened by shrinkage and voids.
It will not cause any deformation.

In addition, in Fig. 7, there are two exhaust holes 17 and two weirs 19A.
Another example using this example will be shown.

(f) Effects of the invention The effects of the present invention are listed below.

The foam insulation material heading toward the exhaust hole is detoured by the weir, and the foam insulation material is placed in a part of the space that should be upstream in the flow direction of the foam insulation material as seen from the exhaust hole before the area near the side of the exhaust hole of the weir. , it is possible to prevent foaming defects in the space that should become the upstream region.

lying in the space near the exhaust hole and upstream in the flow direction of the foam insulation material when viewed from the exhaust hole;
A weir is placed to block a part of the space and obstruct the flow of the foam insulation material toward the exhaust hole, and the flow of the foam insulation material is divided into two directions and detoured. Since they can be merged near the exhaust hole, air can be vented well near the exhaust hole, and defective foaming on the side surface of the exhaust hole of the weir can be prevented.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of the foaming process showing an embodiment of the method for manufacturing a heat insulating box according to the present invention, Fig. 2 is a longitudinal cross-sectional view of the box in the preparation stage of the foaming process, and Fig. 3 is Fig. 1A-
A′ sectional view, FIG. 4 is an overall front perspective view of the heat insulating box obtained by the present invention, and FIG. 5 is FIG. 4 B-
6 is a sectional view taken along line C-C' in FIG. 4, and FIG. 7 is a plan view of a main part of another embodiment of the present invention. 8...Inner box, 9...Outer box, 10...Foam insulation material, 17...Exhaust hole, 19A...Weir.

Claims (1)

[Scope of Claims] 1. Connect both the inner and outer boxes to form a space between the two boxes to be filled with foam insulation material, and during the foaming process, inject the stock solution of foam insulation material into the space from the injection hole of the outer box. In the method for manufacturing a heat insulating box body, the air in the space is discharged to the outside from an exhaust hole in a wall that is the upper surface of the outer box, and the foam insulation box is foamed in the vicinity of the exhaust hole when viewed from the exhaust hole. A weir is disposed that lies within the space that is the upstream area in the flow direction of the material, blocks a part of the space, and obstructs the flow of the foamed insulation material toward the exhaust hole, and the weir allows the foamed insulation material to A method for manufacturing a heat insulating box body that bypasses heat insulating material and leads it to an exhaust hole. 2. The method for manufacturing a heat insulating box according to claim 1, wherein the weir is made of a heat insulating material.