JPH0784976B2 - Insulation door manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method of manufacturing a heat insulating door having a short shape that closes an opening of a heat insulating box.

(B) Prior art Japanese Utility Model Publication No. 54-45567 (70B22) discloses that a flat surface serving as a front surface, side surfaces obtained by vertically bending four sides of the flat surface, and end portions of each side surface are A heat-insulating door including a box-shaped metal outer plate having a square annular inward flange bent at a right angle to one side, an inner plate, and a foam insulating material filled between the inner and outer plates is shown. R at the first corner between the flat surface and each side surface and at the second corner between each side surface and the inward flange.
It has a face-to-face configuration.

(C) Problems to be Solved by the Invention In the above-mentioned conventional technique, the R-bend is applied to both the first and second corners, but such R-bend is 1 mm or less which is inevitably caused by the bender at a right angle. Is the minimum R of. By assembling such an R-bent outer plate and inner plate and making the outer plate the lower surface, and injecting the undiluted solution of the foamed heat insulating material such as hard polyurethane into the flat surface, the undiluted solution grows into creme, gel and bubbles and solidifies. However, when it changes its flow direction from the horizontal direction to the vertical direction in the cream or gel state during the growth, that is, when it passes through the first corner, it suddenly changes its flow direction. Due to the rising relationship, a swirl occurs at the first corner and a large amount of air is entrained, and when the direction changes from the vertical direction to the horizontal direction in the bubble state, that is, the flow direction changes rapidly even when passing through the second corner. In the upper and second corners as well, a large amount of air is entrained due to the swirling state, and as a result, bubbles larger than the bubbles normally formed in the foamed heat insulating material, that is, air pockets are formed and the boiler is There is a problem to be responsible for the development. In particular, this problem has a strong tendency to appear remarkably when the convection method with a high expansion ratio is adopted. In addition, since the first corner is almost a right angle, when an impact is applied to the vicinity of the first corner of the flat surface from the outside, the elasticity of the first corner is small and the flat surface is likely to be dented. There was also.

The present invention is intended to solve the above problems,
During the foaming process, the flow of the foamed heat insulating material at the first and second corners is improved.

(D) Means for Solving the Problem As a means for solving the above problems, the present invention provides a flat surface, side surfaces obtained by vertically bending four sides of the flat surface, and end portions of the side surfaces. A box-shaped metal outer plate having a square annular inward flange bent inwardly at a right angle, an inner plate, and a heat-insulating door comprising a foamed heat insulating material filled between the inner and outer plates, The first corner between the flat surface and each side surface and the second corner between each side surface and the inward flange are R surfaces, and the bend R of the second corner is set larger than the minimum bend R, In addition, the bend R at the first corner is formed larger than the bend R at the second corner, the stock solution of the foam heat insulating material is injected onto the flat surface with the flat surface of the outer plate as the lower surface, and the foam heat insulation between the inner and outer plates is performed. We adopted a manufacturing method of a heat-insulating door that is filled with material.

(E) Action According to the above means, the foamed heat insulating material that is injected into the flat surface of the outer plate and grows and changes into each state of cream, gel, and foam passes through the first corner in the cream or gel state having a fast growth rate. In this case, since the R surface of the first corner having a large bend R smoothly guides the foam heat insulating material upward, the growth rate does not extremely decrease as compared with the minimum bend R, and therefore the foam heat insulating material There is almost no overflow of air and air entrainment can be avoided. Similarly, when the foam insulation passes through the second corner in a foam state, the foam insulation can be smoothly moved laterally on the R surface of the second corner. Because of the guiding function, the growth rate does not extremely decrease even in the foam state, and it is possible to avoid generation of vortex and entrainment of air in the foamed heat insulating material.

(F) Embodiment An embodiment of the present invention will be described below with reference to the drawings.
(1) is a refrigerator body composed of a heat-insulating box body having a front opening (1A), and a heat-insulating door (2) for opening and closing the front opening (1A)
Is rotatably provided.

The heat-insulating door (2) is formed by bending four sides of a flat surface (3A), which is the front surface of the door, vertically, and bending the ends of each side (3B) inward. A box-shaped stainless steel outer plate (3) having an inward flange (3C), a door inner plate (4) made of ABS resin, and an extrusion molded product of resin such as vinyl chloride, both plates (3), It is composed of an elastic hard frame (5) annularly arranged between (4) and a foamed heat insulating material (6) filled in the space between both plates (3) and (4).

The outer plate (3) has an annular first corner (C1) formed between the flat surface (3A) and each side surface (3B) and each side surface (3B).
Second ring formed between the and the inward flange (3C)
The corner (C2) is the R side. The second corner (C2) has a bending radius of, for example, 3 mm, which is larger than 1 mm or less, which is usually said to have the smallest bending radius, and the first corner (C1) has a larger bending radius than the second corner (C2). The bend radius is 6mm.

The frame (5) extends on the inward flange (3B) of the outer plate (3), and the arrow-shaped snap (8) of the gasket (8) defines a dovetail groove (7) having an opening facing outward. 8A) and a base portion (11) that defines a groove (10) that is spaced from the holding portion (9) and that protrudes forward from the holding portion (9) and is inserted into the inward flange (3C). ) And a mounting portion (12) that extends in the opposite direction to the base portion (11) and on which the peripheral end surface of the inner plate (4) is mounted.

As shown in detail in FIG. 8, the frame (5) has two elongated frame sides (5-1) (5-2) before assembly.
Both ends are cut perpendicularly to the sides in the longitudinal direction, and a small connecting portion (13) that can be bent and broken at a proper position of the base portion (11) corresponding to the corner portion of the inward flange (3C). ) Is left to form two cut portions (14) which are cut substantially at right angles.

Therefore, when each frame side (5-1) (5-2) is bent in a U shape so that each connecting portion (13) is on the outside, a corner portion has a right-angled annular shape as shown by a chain double-dashed line. The frame (5) will be constructed. In addition, the frame (5) is replaced with the frame sides (5-1) (5
-Twisting of the side (5B), which is a linear part, is reduced due to the two parts.

This frame (5) is inserted into the inward flange (3C) of the outer plate (3) whose perspective view is shown in FIG. First, as one assembling procedure, the side (5A) of the frame (5-1) to be inserted into the upper and lower sides of the flange (3C) of the door (2) is inwardly or outwardly utilized by utilizing its elasticity. Bend it slightly in the direction and insert it into the flange (3C), and then insert both sides (5B) into the door (2).
Insert into the sides of the flanges (3C) on the left and right of to complete the assembly. At this time, since the base portion (11) projects forward from the holding portion (9), the upper surface of the base portion (11) serves as a guide surface,
The insertion work into the flange (3C) can be done easily.

In addition, as other assembly procedures, (5-1) (5-2)
Even if one of the connecting parts (13) is cut off, it is inserted into the inward flange (3C) of the outer plate (3) in an L-shaped state, and then the separated side (5B) is inserted to complete the assembly. Good. In this case, since the side (5A) and the side (5B) are connected only by the connecting portion (13) at the tip of the base portion (11), they can be easily separated without using any tool or the like.

As another assembly procedure, as shown in FIG. 7, the frame side (5
-1) Make one of the cut parts (14) of (5-2) an obtuse angle and fold the obtuse cut part (14) side (5B) at an obtuse angle with respect to the side (5A) as shown by the chain line. After bending, return it to the position shown by the chain double-dashed line and insert it into the groove (10) into the inward flange (3C) so that both frame sides (5-1) (5-2) are inward flange (3C). Mounted on.

(15) shown in FIG. 1 and FIG. 8 is both frame sides (5-1)
A tape-shaped sealing member that covers a slight gap formed between the abutting portions of (5-2), and has both frame sides (5-1) (5
-2) is provided across the adjacent side (5B) which is a straight line portion. The gap is about 1 mm and each frame side (5-1) (5
-2) It is set in consideration of the dimensional error due to bending.

After the frame (5) is attached to the inward flange (3C), the door outer plate (3) is set on the box-shaped lower jig (16) shown in FIG. Immediately after injecting the foaming undiluted solution (6A) of the foam insulation material (6) onto the flat surface (3A) of the door outer plate (3), the door inner plate (4) is placed on the mounting portion (12) of the frame (5). Place it and fix the door inner plate (4) with the upper jig (17).
The foaming undiluted solution (6A) becomes a foam insulation material (6) through a cream, gel, and foam state, and during this, air between the door outer plate (3) and the door inner plate (4) is pushed out from the exhaust hole (18). .

According to such a manufacturing method, the foamed heat insulating material (6), which is injected into the flat surface (3A) of the outer plate (3) and changes its growth state into cream, gel, or foam, is a cream with a high growth rate or When passing through the first corner (C1) in the gel state, bend R
Since the R surface of the first corner (C1), which has a large radius, smoothly guides the foamed heat insulating material (6) upward, the growth rate does not extremely decrease as compared with the minimum bending R, and thus foamed heat insulating There is almost no overflow of the material (6), air entrapment can be avoided, and similarly, when the foam insulation material (6) passes through the second corner (C2) in a foam state, the second corner (C2)
Since the R surface smoothly guides the foamed heat insulating material (6) in the lateral direction, the growth rate does not extremely decrease even in the foam state, and the overflow of the foamed heat insulating material (6) occurs. Also, air entrapment can be avoided.

In addition, since the first and second corners (C1) and (C2) are set to a bend R that is larger than the minimum bend R, the elasticity at the corners, that is, the elastic restoring force is large compared to the corner of the minimum bend R, It is less likely to be deformed by an impact from one side, and the strength of the flat surface edge before and after the foaming step can be increased.

(G) Effects of the Invention According to the present invention described above, the effects listed below occur.

In the foaming process, when the cream or gel having a high growth rate is passed through the first corner, the first bend R is large.
Since the R surface of the corner smoothly guides the foamed heat insulating material upward, the growth rate does not extremely decrease as compared with the minimum bending R, and therefore the vortex flow of the foamed heat insulating material is hardly generated and In order to avoid the entrainment, and similarly, when the foam end heat material passes through the second corner in a foamed state, the R surface of the second corner smoothly guides the foam heat insulating material in the lateral direction. Even in the foam state, the growth rate does not extremely decrease, and it is possible to avoid generation of vortex and entrainment of air in the foamed heat insulating material. As a result, it is possible to manufacture a heat-insulating door that does not cause voids, that is, does not cause defective foaming.

Since the first and second corners have a bend R that is larger than the minimum bend R, the elasticity at the corners, that is, the elastic return force, is larger than that of the corner with the minimum bend R, and it is deformed by an impact from the outside. It becomes difficult to increase the strength of the edge of the flat surface before and after the foaming process.

[Brief description of drawings]

FIG. 1 is a vertical view of the heat insulation door of the present invention when foaming, FIG.
The figure is a perspective view of a refrigerator provided with the heat insulating door of the present invention, FIG. 3 is a sectional view taken along the line AA of FIG. 2, FIG. 4 is a perspective view of a door outer plate, and FIG.
The figure is a plan view showing a state where the sash is attached to the door outer plate,
FIG. 6 is a sectional view taken along the line BB of FIG. 5, FIG. 7 is a plan view of a main portion of another embodiment, and FIG. 8 is a plan view of a frame. (3) …… Outdoor plate, (3A) …… Flat surface, (3B) …… Side surface, (3C) …… Inward flange, (4) …… Door inner plate,
(6) …… Foam insulation, (6A) …… Undiluted solution, (C1) …… First corner, (C2) …… Second corner.

Claims (1)

[Claims] 1. A flat surface, four side surfaces formed by bending four sides of the flat surface vertically, and a square annular inward flange formed by bending the ends of the side surfaces inward at right angles. In a heat-insulating door comprising a box-shaped metal outer plate, an inner plate, and a foamed heat insulating material filled between the inner and outer plates, a first corner between the flat surface and each side and each side Each of the second corners with the facing flange is an R surface, and the second corner bends R
Is larger than the minimum bend R, and the bend R at the first corner is made larger than the bend R at the second corner,
A method of manufacturing a heat-insulating door, which comprises injecting a stock solution of a foamed heat insulating material into the flat surface with the flat surface of the outer plate as a lower surface and filling the foamed heat insulating material between the inner and outer plates.