JPS634114B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a metal box that constitutes an outer box of a refrigerator or the like by bending a pre-painted steel plate.

(B) Conventional technology As disclosed in Japanese Utility Model Publication No. 46-12755, this type of box body is conventionally made by bending a steel plate and then spot welding the overlapping parts of the corners of the front flange to form a box body. had been completed. This was not a problem because the painting was done after the box was completed, so any traces of spot welding would be hidden by the painting, but in recent years there has been a trend to use pre-painted steel plates as materials, and in this case it is It was not possible to perform spot welding after forming the curve. Therefore, when using a pre-painted steel plate, as shown in FIGS. 4 and 5, a notch 2 is provided in the front flange 1 of the box, and a stepped portion 3 is formed around the notch, By inserting a synthetic resin corner piece 4 flush with the front flange 1 between the stepped portion and the notch 2, the notch 2 and the cut surface 5 were concealed (in practice). (Refer to Publication No. 1987-90752).

However, in the conventional structure using the corner piece 4 described above, the number of parts increases by the provision of the corner piece 4, which increases the number of man-hours and increases the cost. There were disadvantages such as giving a strange feeling and spoiling the aesthetic appearance of the corners.

(c) Problems to be Solved by the Invention The present invention solves the above-mentioned drawbacks, and hides the cut surface of a painted steel plate and makes the front flange of the corner flush with the other one without using a corner piece. This is what we aim to do.

(d) Means for solving the problem The present invention involves bending a pre-painted steel plate to form a box body from a top wall, side walls, etc., and bending the opening edge of the box body inward. A bent flange is formed by bending at a substantially right angle, and adjacent bent flanges are brought into contact and overlapped with each other at a corner of the opening edge, and the upper bent flange of the overlapping portion is tilted. A folded piece is formed by bending inward at an appropriate curvature along the folding line, and a step piece is formed on the lower bending flange along the folding line of the upper bending flange, and the step piece is By abutting and superimposing the folded pieces, adjacent bent flanges at the corner portions are made substantially flush with each other.

(E) Function According to the present invention, the upper bent flange of the overlapping portion is folded inward, and the lower bent flange is overlapped with the back side of the upper bent flange, so that the cut surfaces of both bent flanges are Not exposed together. Furthermore, even if the upper bent flange moves forward by an appropriate amount of curvature based on the point where the double bent flanges contact and overlap, the lower bent flange also moves forward by a paragraph, so that the outer surface of the double bent flange is Aligned flush. Further, in the overlapping portion, both the upper bent flange and the lower bent flange are bent with appropriate curvatures, so that no cracks occur in the coating film.

(F) Embodiment Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

Reference numeral 6 denotes a box body composed of a top wall 7, both side walls 8, 8, and a bottom wall 9 formed by bending or bonding pre-painted steel plates.
The opening edge of each predetermined wall such as 8 is bent inward at a substantially right angle to form bent flanges 10, 11, 11, respectively. The bent flanges 10, 11, 11 abut and overlap each other at adjacent corner portions. Of the overlapping bending flanges 10 and 11, the overlapping end of the upper bending flange 11 located above tilts the bending line in a substantially diagonal direction, and the coating film is cracked without coming into close contact with the back. The folded piece 12 is bent to have a substantially ⊃-shaped cross section with an appropriate curvature that is not too much, and is spaced apart from the upper bent flange 11, and the overlapping end of the lower bent flange 10 located below is A step piece 14 is formed by bending the upper bending flange 11 backward in steps by the amount of curvature along the bending slope line 13, and this step piece 14 is attached to the back surface of the folded piece 12 directly or through a sealing material. Contact polymerization is carried out.
Therefore, the level of the stepped pieces 14 is approximately equal to the distance from the outer surface of the upper bent flange 11 to the back surface of the folded piece 12. Incidentally, it is effective to spot weld the overlapping portions of the folded pieces 12 and the stepped pieces 14 as needed, but this is not always necessary.
Furthermore, after the box body 6 is completed, a predetermined inner box (not shown) is housed and arranged, and a heat insulating material (not shown) is foamed and filled between the box body 6 and the inner box, so that the paragraph piece 14 can be attached to the back surface of the box body 6. By receiving the foaming pressure from the side and coming into close contact with the folded piece 12, the surface angle between the upper folded flange 11 and the lower folded flange 10 becomes more accurate, and in this state, the folded piece 12 and the stepped piece 14 are The polymerized portion is embedded in the insulation material.

(G) Effects of the Invention Since the present invention is constructed as described above, the overlapping end of the upper bending flange of the overlapping portion is inclined and folded back, but the so-called proper folding is not performed. It can be folded back with a certain curvature, the coating on the folded line can be maintained in good condition without cracking the coating film, the design effect can be maintained well, and there is almost no need for repair work after formation. Furthermore, the lower bent flange of the overlapping portion can be formed into a step with an appropriate curvature as the upper bent flange is folded back, and like the upper bent flange, no cracks will occur in the coating film. In addition, the overlapping portions of the upper and lower bent flanges do not have a large step difference, and can be located substantially on the same plane. In addition, most of the bent ends exposed on the outer surface are curved surfaces, and the cut end surface of the flange is not exposed, so even if the user touches it, there is no chance of injury. The corner piece for concealment can be omitted, and therefore, the number of parts and the associated work man-hours can be reduced by the amount of the omission, and manufacturing costs can be reduced.

Furthermore, when the overlapping portion of the folded piece and the stepped piece is buried in the foamed heat insulating material, the bond between the two pieces becomes strong, and the same effect as spot welding can be expected.

[Brief explanation of the drawing]

Fig. 1 is a schematic perspective view of the metal box of the present invention, Fig. 2 is an enlarged perspective view of circle A in Fig. 1, Fig. 3 is a sectional view taken along line B-B in Fig. 2, and Fig. 4 is a conventional example. The explanatory drawing, FIG. 5, is a sectional view taken along line CC in FIG. 6...Box body, 7...Top wall, 8...Side wall, 10...Lower side bending flange, 11...Upper side bending flange, 12...
Folding piece, 13... Folding line, 14... Paragraph piece.

Claims (1)

[Claims] 1. A box body is formed from the top wall, side walls, etc. by bending a pre-painted steel plate, and the opening edge of this box body is bent inward at a substantially right angle to form a bent flange. , the adjacent bent flanges are brought into contact and overlapped with each other at the corner of the opening edge, and the upper bent flange of the overlapping portion is further bent inward at an appropriate curvature along the inclined folding line. to form a folded piece, and form a stepped piece on the lower bent flange along the folding line of the upper bent flange, and then contact and superpose the folded piece on the stepped piece, thereby forming a corner part. A metal box body characterized by adjacent bent flanges being substantially flush.