JPH01134194A - Manufacture of heat-insulating wall - Google Patents

Abstract

PURPOSE: To increase the rigidity of a shell and form a rugged surface on a heat insulator by providing a flexible and open cell formed sealing sheet impregnated with a foamable resin injected and foamed in the shell; the sheet being stretched over an open face of the shell. CONSTITUTION: A door outer shell 11 is like a shallow rectangular vessel open at the top face, the back side. A flexible and open cell formed paper 13 having numberless small vent holes over one side is pasted to a sheet for sealing the open back side of the shell 11. A foamable resin in injected and foamed in the shell 11 to fill up its interior while the resin comes into contact with the sheet 12 and is forced to impregnate therewith. This impregnating of the foamable resin increases the rigidity of the shell 11 and forms a rugged surface on the to heat insulator.

Description

[Detailed description of the invention] [Object of the invention] (Industrial field of application) The present invention relates to the manufacture of a heat insulating wall that is manufactured by filling a heat insulating material made of a foamed resin into an outer shell that is open on one side. The present invention relates to a method, and particularly to an improved method in which rigidity can be increased by utilizing a member for sealing the open surface of an outer shell.

(Prior Art) For example, a heat insulating door for a refrigerator has conventionally been constructed by filling a door shell mainly made of a metal plate with a heat insulating material made of foamed resin, such as foamed urethane. Since a plastic door inner plate is attached to the back side of the door outer membrane after filling with a heat insulating material, the back side of the door outer membrane is open.

When filling a foamed resin into such a door shell with an open back surface, in order to prevent the resin from leaking from the open back surface, conventionally, as shown in FIG.
A paper sheet 2 is placed on the back surface of the door to seal the open back surface, and in this state, the foamable resin stock solution 4 injected into the door outer membrane 1 is foamed. In addition, since the back side of the door outer membrane 1 is open, the rigidity of the back side is relatively low, and even though the door inner plate will be attached later, the door inner plate is made of plastic and has low rigidity. You can't expect that much increase in rigidity. Therefore, conventionally, in order to increase the rigidity of the back side of the door outer membrane 1, a reinforcing plate 3 was attached to the paper sheet 2.

(Problems to be Solved by the Invention) However, in the above conventional configuration, the TJI of the reinforced tM3
Since m is relatively large, the paper sheet 2 becomes dish-shaped and slips into the door outer membrane 1, as shown by the two-dot chain line in FIG. 3, and this causes large "wrinkles" on the paper sheet 2. The sealing effect on the back surface of the door outer membrane 1 will be impaired due to such a situation. In addition, since the inner door plate has an uneven shape due to the formation of pockets for storing bottles, etc., even if you try to form the back side of the heat insulating material into an uneven shape to match the shape of the inner door plate, the reinforcing plate 3 will not work properly. Therefore, there was a problem that such molding was difficult.

Therefore, an object of the present invention is to be able to increase the rigidity of the outer shell without impairing the sealing properties of the open surface of the outer shell, and to
To provide a method for manufacturing a heat insulating wall, which also allows for forming unevenness on the surface of a heat insulating material.

[Structure of the Invention] (Means for Solving the Problems) The method for manufacturing a heat insulating wall of the present invention includes providing a sealing sheet made of a soft open cell on the open surface of an outer shell, and adding a foamed resin undiluted solution. The sheet is characterized in that the sheet is impregnated with a foamable resin by foaming.

(Function) The foamable resin impregnated into the sheet consisting of open cells is
Because it is dense and the density of the resin is high, the rigidity of the outer shell is high. Furthermore, since the sheet is soft, the heat insulating material can be molded into an uneven shape by pressing it with a molding jig.

(Example) An example in which the present invention is applied to a heat insulating door of a refrigerator will be described below with reference to FIGS. 1 and 2.

Reference numeral 11 denotes a door outer membrane formed of, for example, a metal plate, which has the shape of a rectangular container with a shallow bottom, and its rear surface, which is the upper surface in the figure, is open. Reference numeral 12 denotes a sheet for sealing the open back surface of the door outer membrane 11, which is made of a soft open-cell material such as urethane foam, and has numerous small holes (not shown) for degassing on one side. Paper 13 is pasted.

Now, in order to fill the door outer membrane 11 with a heat insulating material, first install the door outer membrane 11 with the back side facing up, as shown in FIG. Then, the sheet 12 is pressed against the flange lla on the back side of the door outer membrane 11 using a pressing jig (not shown).

In this state, a foamable resin stock solution 14 is injected into the door outer membrane 11 from an injection hole (not shown), and is foamed. Due to the foaming of the stock solution 14, the door outer membrane 11 is filled with foamable resin as shown in FIG. 1, and is filled as a heat insulating material 15.

By the way, the foamable resin comes into contact with the sheet 12 in the process of filling the door outer membrane 11 due to its foaming. Then, the sheet 12 becomes urethane foam (open cell).
Since the sheet 12 is made of aluminum, the foamable resin is impregnated into the sheet 12. In this case, the sheet 12 absorbs only the resin content of the foamable resin, or the large bubbles in the foamable resin break in the process of penetrating into the open cells of the sheet 12. The impregnated foamable resin becomes dense and has a high resin content, and becomes hard and highly rigid in the solidified state, and there is a risk that it will peel off together with the foamable resin (insulation material 15) in the door outer membrane 11. Nor. Therefore, the rigidity of the door outer membrane 11 can be increased by the foamable resin A impregnated into the sheet 12. Moreover, since the sheet 12 is light, when it is placed on the flange llH of the door outer membrane 11, it does not hang down significantly into the door outer membrane 11, and the sealing performance against the back side of the door outer membrane 11 is not impaired. .

Furthermore, since the sheet 12 is soft, if the holding jig is provided with unevenness, the sheet 12 will be deformed freely by the foaming pressure of the foaming resin to follow the uneven surface of the holding jig (molding jig). Therefore, it is possible to form irregularities on the surface of the heat insulating material 15.

Note that the sheet 12 is not limited to being made of urethane foam, but may be any soft open-cell material. Also, paper 1 of sheet 12
3 is not necessary.

[Effects of the Invention] As explained above, according to the present invention, a sheet made of soft open cell foam is used as a member for sealing the open surface of the outer shell, and the foamable resin is expanded into the sheet by foaming the foamable resin. The foamed resin impregnated into the sheet does not impair the sealing performance of the outer shell against the open surface, and the rigidity of the outer shell can be increased by the foamed resin impregnated into the sheet. This has an excellent effect in that it can be formed into an uneven shape.

[Brief explanation of the drawing]

Figures 1 and 2 show an embodiment of the present invention; Figure 1 is a vertical cross-sectional view of the heat insulating door in its completed form, and Figure 2 is a vertical cross-sectional view of the same when the undiluted solution is foamed. FIG. 3 is a diagram corresponding to FIG. 2 showing a conventional example. In the figure, 11 is the door shell, 12 is the sheet, 14 is the undiluted solution, and 15
is an insulating material. Applicant Toshiba Corporation Figure 1 Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A heat insulating material made of a foamable resin is injected into an outer shell that is open on one side, and the heat insulating material is filled into the outer shell by foaming the solution, and the open surface of the outer shell is filled with the heat insulating material. 1. A method for manufacturing a heat insulating wall, comprising: providing a sealing sheet made of soft open cell foam, and impregnating the sheet with a foamable resin by foaming the raw solution.