Method of making a panel corner

Abstract

A method of making a corner for a panel from a piece of sheet-metal by cutting said metal to provide a panel surface having a pair of edges disposed at an angle to each other with a cut-out formed in the corner thereof. The metal is then bent to form a pair of skirts extending downwardly from said edges with the adjacent ends of the skirts in spaced relation. An adhesive filler is applied to the inner skirt faces and fills the space between the adjacent skirt ends.

Description

BACKGROUND OF THE INVENTION

In forming a right angled corner for a sheet-metal panel having a depending skirt, it has been the common practice to make a simple right angled cut-out at the corner of a sheet of metal. The sheet is then bent along a pair of angularly disposed bend lines to form the skirts at the panel corner. Because of the right angled cut-out at the corner at the sheet, the adjacent edges of the skirts will be disposed in abutting relation at the corner of the panel.

Lack of precision in such bending operations and in making the cut, however, frequently results in misalignment of the adjacent edges of the skirts. This results in sharp edges and raw metal being present at the corner. To correct this, the corners have been formed, then welded, then ground down, and finally painted. This is a laborious and expensive procedure.

It is an object of this invention, to provide a method of making a corner for a panel which will overcome these difficulties and disadvantages. More specifically, it is an object of the invention to provide a method of making such a corner in which the metal is cut in a manner to provide a predetermined spacing between certain of the corner components of the panel which can be filled with a decorative material.

SUMMARY OF THE INVENTION

In accordance with one form of the invention, as it is employed to form a right angled panel corner having underlying stiffening flanges, a piece of sheet-metal is cut to define a pair of first edges normal to each other. At points spaced equal distances from what would otherwise be the juncture of the first edges, a second pair of edges are cut which extend inwardly at a 45.degree. angle from said first edges. A third pair of edges normal to each other are cut to extend inwardly from points adjacent the inner edges of the second edges. Each of said third edges is offset from the adjacent second edge longitudinally away from the corner to be formed.

After the cutting operation, the metal is bent along a pair of first bend lines parallel with said first edges and spaced inwardly therefrom so as to terminate at the offsets between said second and third edges. The metal is then bent along a pair of second bend lines parallel with said first bend lines and spaced inwardly therefrom so as to terminate at the juncture of said third edges. Each of said bending operations bends the metal through a 90.degree. angle so that the edges of the panel surface are defined by the second bend lines, a pair of skirts extend downwardly from the panel surface between the first and second bend lines, and inwardly projecting flanges extend under the panel surface from the first bend lines. Because of the configuration of the second and third edges, the ends of the flanges will abut each other, but the ends of the skirts will be disposed in spaced relation to one another.

After the corner has been cut and bent, it is placed in a mold, and a thermoplastic adhesive filler is injected against the inwardly presented faces of the skirts and flanges. The adhesive filler is allowed to cure into a rigid state to bind the ends of the skirts and flanges together and form a decorative bead filling the space between the ends of the skirts.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the invention. In such drawings:

FIG. 1 is a perspective of a panel corner made according to the invention, but with portions thereof being broken away;

FIG. 2 is a metal blank cut to form the corner shown in FIG. 1;

FIG. 3 is a perspective view of the blank shown in FIG. 2 bent to form the corner shown in FIG. 1;

FIG. 4 is a horizontal section through a mold showing the addition of the adhesive filler to the corner;

FIG. 5 is a perspective view of a modified form of the panel corner shown in FIG. 1 and made according to the invention;

FIG. 6 is a metal blank cut to form the corner shown in FIG. 5; and

FIG. 7 is a perspective view of the blank shown in FIG. 6 bent to form the corner shown in FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in FIG. 1, a panel having a right angled corner made according to the invention comprises a supporting surface 10 having a pair of skirts 11 and 12 extending downwardly therefrom. Flanges 14 and 15 project inwardly from the lower ends of skirts 11 and 12, respectively, in parallelism with the surface 10. The apex of the corner is defined by a decorative plastic bead 16 extending between the adjacent ends of the skirts.

The panel is formed from a sheet-metal blank which, as shown in FIG. 2, is cut to define a pair of edges 18 and 19 normal to each other, said edges constituting the inner edges of flanges 14 and 15 in the finished corner. During the cutting operation, a second pair of edges 21 and 22 are formed which project inwardly at 45.degree. angles from points equally spaced from what would otherwise be the juncture of the edges 18 and 19. The adjacent ends of the edges 21 and 22 are offset, as at 24 and 25, longitudinally away from the inner ends of edges 21 and 22. The cutting operation also forms a third pair of edges 27 and 28 which extend inwardly from the offsets 24 and 25 and define the ends of the skirts 11 and 12, respectively, in the finished corner. As shown, the edges 27 and 28 are at an angle of 90.degree. with respect to each other, and the included angle between each of said third edges and its associated second edge is 135.degree..

After the blank has been cut, it is bent along two pairs of bend lines 30 and 31 and 32 and 33. The lines 30 and 31 are parallel with the edges 18 and 19 and extend longitudinally from the offsets 24 and 25. The bend lines 32 and 33 are parallel with the bend lines 30 and 31, respectively, and extend longitudinally from the edges 27 and 28 adjacent their juncture. During such bending, the metal is bent 90.degree. about the axis of each bend line so that bend lines 30 and 31 define the junctures of the skirts and flanges, and the lines 32 and 33 define the junctures between the skirts and the panel surface 10.

As is shown in FIG. 2, the edges 27 and 28 are cut such that their juncture 35 is the arc of a circle. The center of the circle of which the juncture 35 is a segment is the juncture of projections of the bend lines 32 and 33 and is indicated in FIG. 2 at point A. The junctures of the offsets 24 and 25 with edges 27 and 28 also constitute the arcs of circles which have the same radii as the arc juncture 35. Thus, when the blank is bent into the corner configuration shown in FIG. 3, the edges 21 and 22 will abut each other, but the edges 27 and 28 will be spaced apart throughout their lengths by a distance equal to the length of a chord extending across the arc juncture 35.

After the blank has been bent into the corner configuration shown in FIG. 3, it is placed in a mold 40, as shown in FIG. 4, with the surface 10, skirts 11 and 12, and flanges 14 and 15 abutting the mold faces. An adhesive filler material 42 is then injected as by a nozzle 43, into the mold against the inner faces of the skirts 11 and 12, flanges 14 and 15 and bottom face of the panel surface 10. The material 42 fills the space between the skirts 11 and 12 and bridges across said skirts as well as the flanges 14 and 15. As shown in FIG. 1, after the material 42 has been cured, the panel is removed from the mold, with said material forming the bead 16 closing the space between the skirt edges.

The adhesive filler material 42 is a thermoplastic material which can be injected into the mold in a fluid state and then will cure into a rigid state to form the bead 16. Examples of such materials are resins of the polyolefins, polyesters, polyamides, and vinyl copolymers. As will be understood, the adhesive filler material can be color treated and the mold cavity can be contoured to give the bead 16 and desired appearance and configuration.

The panel corner illustrated in FIG. 5 is like that illustrated in FIG. 1 except that it does not have the flange 14 and 15. Thus, it is provided with a panel surface 10' having skirts 11' and 12' depending from the edges thereof.

The panel is formed from a sheet-metal blank which, as shown in FIG. 6, is cut to define a pair of edges 18' and 19' normal to each other, said edges constituting the bottom edges of the skirts in the finished corner. During the cutting operation, a second pair of edges 27' and 28' are formed which project inwardly at 90.degree. angles from the edges 18' and 19'. As with the embodiment shown in FIGS. 1-4, the edges 27' and 28' are cut such that their juncture 35' is on the arc of a circle. The center of that circle, indicated at A' in FIG. 6, is the juncture of projections of bend lines 32' and 33' which are parallel to the edges 18' and 19' and define the interconnections of the skirts with the panel surface 10'.

After the blank has been cut, it is bent through an arc of 90.degree. around the bend lines 32' and 33' so that the skirts 11' and 12' project downwardly from the edges of the panel surface 10', as shown in FIG. 7. As shown, the edges 27' and 28' of the skirt are disposed in spaced parallel relation, the spacing being equal to the length of a chord across the arc segment 35'.

After the bending operation, the panel is placed in a mold, and an adhesive filler is injected therein between the edges 27' and 28' to fill the space therebetween and bridge across the adjacent skirt edges in the manner previously described in connection with FIG. 4. This forms the bead 16' between the skirt ends.

While each of the embodiments has been shown and described in connection with the manufacture of a panel having a right angled corner, it is to be understood, of course, that the corner may have any desired angle.

Claims

We claim:

1. A method of making a corner for a panel, comprising the steps of cutting a sheet of metal to form a pair of first edges at an angle to each other, a pair of second edges extending inwardly from said first edges at points equally spaced from what would otherwise be the juncture of said first edges, a pair of their edges extending inwardly from points adjacent the inner ends of said second edges, said third edges being offset from said second edges and having their inner ends interconnected by an arc segment; bending said sheet along a pair of first bend lines parallel to said first edges and extending longitudinally from the offsets between said second and third edges, and along a pair of second bend lines parallel with said first bend lines and extending longitudinally from the ends of said arc segment whereby the metal between said first and second bend lines defines a pair of skirts whose adjacent ends defined by said third edges are in spaced relation, and the metal between said first bend lines and first edges defines a pair of flanges whose adjacent ends defined by said second edges are in abutting relation; placing said metal in a mold; injecting an adhesive filler into said mold to fill the space between said skirts and bridge across the adjacent ends of said skirts and flanges, and curing said adhesive filler into a rigid state.

2. A method of making a corner as set forth in claim 1 in which said third edges are joined to said offsets on arcs having the same radii of curvature as said arc segment.

3. A method of making a corner as set forth in claim 1 in which said arc segment is the center of a circle whose center is defined by the intersection of projections of said second bend lines, and said third edges are joined to said offsets on arcs having the same radii of curvature as said arc segment.

4. A method of making a corner as set forth in clam 1 in which the included angles between adjacent ones of said first and second edges and between adjacent ones of said second and third edges are 135.degree. and the included angle between said first edges is 90.degree., and said metal is bent 90.degree. about the axis of each of said first and second bend lines.

5. A method of making a corner for a panel, comprising the steps of cutting a sheet of metal to form a pair of first edges at an angle to each other and a pair of second edges extending inwardly from said first edges at points equally spaced from what would otherwise be the juncture of said first edges whereby said second edges define a cut-out portion at the corner of said sheet, said cutting operation defining an arcuate segment in said sheet interconnecting the adjacent ends of said second edges; bending said sheet along a pair of bend lines parallel to said first edges and extending longitudinally from the ends of said arc segment whereby the metal between said bend lines and first edges forms a pair of skirts whose adjacent ends are in spaced relation and are defined by said second edges; placing said metal in a mold; injecting an adhesive filler into said mold to fill the space between said second edges and bridge across the adjacent ends of said skirts; and curing said adhesive filler into a rigid state.

6. A method of making a corner as set forth in claim 5 in which said arc segment is the segment of a center whose center is defined by the intersection of projections of said bend lines.

7. A method of making a corner as set forth in claim 5 in which the included angles between said first edges, between said second edges and between said first and second edges are 90.degree., and said metal is bent 90.degree. about the axes of said bend lines.