JPS6029580A - Manufacture of heat-insulating wall body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a heat insulating wall made of a foamable heat insulating material such as rigid urethane foam.

Conventionally, the heat insulating door 2 of the vending machine 1 is made of a heat insulating wall, as shown in FIGS. A back plate 4 made of a synthetic resin material and having a thickness of approximately 1 to 2 m11 is fixed to the face plate 3 and the open back side of the face plate 3, and a foaming solution of hard urethane is injected into a mold to harden the foam. It is composed of

However, the conventional heat insulating door 2 described above has the disadvantage that wrinkles are formed on the flat back plate 4 due to the expansion and propagation of the foam, reaction heat, and foaming pressure when the foam hardens in the mold, resulting in poor appearance. was.

The present invention eliminates the above-mentioned drawbacks, and provides a method for manufacturing an insulated door that is easy to manufacture, lightweight, and inexpensive, and does not cause wrinkles on the back plate even if a thin synthetic resin plate is used for the back plate of the insulated door. It is something to do.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a heat insulating door of a vending machine will be described below with reference to the drawings. Figure 3 shows the molding state, 5
The mold is composed of an upper mold 6 and a lower mold 7, and the bottom of the lower mold 7 is provided with an unevenness 9 consisting of a plurality of protrusions 8, and inside the lower mold 7, the periphery is formed on both sides in the open part of the back surface of the surface 1ii+3. Insert the insulating door box body 10 with the back plate 4 attached with adhesive tape, etc., and insert the lower mold 7.
After placing and fixing the upper mold 6 on the open upper surface of the mold, a foaming solution of hard urethane is injected from a plurality of locations as shown by the arrows, and after it hardens, it is taken out from the mold 5 as a heat insulating door 2'.

At this time, since the unevenness 9 of the back plate 4 and the lower mold 7 are formed facing each other, the unevenness 9 forms unevenness 11 along the protrusions 8 on the back plate 4 due to the reaction heat of the foaming stock solution and the foaming pressure. be done.

Since the unevenness 11 applies an appropriate tensile force to the back plate 4, it has the effect of preventing the generation of wrinkles on the surface of the back plate 4 due to reaction heat and foaming pressure during molding.

Note that 12 is a heat insulating material made of hard urethane foam that has been foamed and hardened.

In the above-described embodiment, a plurality of protrusions 8 were provided as unevenness 9 on the bottom surface of the lower mold 7, but the unevenness 9 may be shaped like a lattice, or
It has been confirmed through experiments that the same effect can be obtained by forming the structure into a net shape or by arranging flat triangular pyramids or quadrangular pyramids in series as shown in FIG.

As mentioned above, the unevenness 9 on the bottom of the lower mold 7 is caused by the unevenness 1 on the back plate 4.
1, it is not necessary to integrally form the unevenness 9 on the bottom surface of the lower mold 7. For example, a perforated plate 13 shown in FIG. 6 may be placed on the bottom surface of the lower mold 7. As shown in FIG. 7, a plurality of thin plates 14 may be placed in parallel at intervals. These perforated plates 13 and thin plates 14 may be fixed using double-sided adhesive tape or the like.

According to the present invention configured as described above, since the unevenness 11 is formed on the back plate 4 of the heat insulating door 2' due to the reaction heat and foaming pressure during foaming of the hard urethane foam stock solution, the heat insulation door 2 made of the hard urethane foam stock solution is formed. This has the effect of preventing the generation of wrinkles on the back plate 4 when forming the ``, and providing an insulated door that is easy to manufacture, lightweight, and inexpensive.Furthermore, the insulated door 2
The unevenness 11 formed on the back plate 4 of ' has a beautiful appearance as a pattern.

Although the above embodiment describes the insulating door of a vending machine, the present invention is not limited to this, and can be implemented by modifying it as appropriate without departing from the scope of the invention, for example, it can be applied as an insulating panel for a prefabricated refrigerator. Of course.

[Brief explanation of drawings]

Fig. 1 is an open perspective view of a vending machine showing an insulating door, which is a conventionally well-known insulating wall, Fig. 2 is a perspective view of the insulating door of Fig. 1, and Fig. 3 is an insulating example showing an embodiment of the present invention. Cross-sectional view of the door molding state,
FIG. 4 is a sectional view showing the heat insulating door after molding, FIG. 5 is a perspective view similarly showing the heat insulating door after molding, FIGS. 6 and 7 are perspective views showing the plate material for forming unevenness, FIG. 8 is a perspective view of the bottom of the lower die on which other irregularities are formed. 2''...Insulation 5i! 3...Front plate 4...Back plate 5...Molding mold 6...Upper mold゛7...Lower mold 8...
・Protrusion 9...Irregularities 11...Irregularities 5-s1 Figure 2 Figure 6, Figure 7, Figure 8

Claims (1)

[Claims] A box body is constituted by a front plate made of a metal plate forming a front surface and a peripheral end surface and an open back side, and a relatively thin back plate made of a synthetic resin material attached to the open back side of the front plate. A box body is inserted into a mold, an unevenness is formed on the inner surface of the mold facing the back plate, a synthetic resin foaming solution is injected into the box body, and the foam is cured to form a heat insulating material. Method for manufacturing a heat insulating wall body with