US3032861A - Method of manufacturing a flatiron - Google Patents

Description

y 8, 1962 H. s. FOSTER 3,032,861

METHOD OF MANUFACTURING A FLATIRON Filed May 27. 1957 fr) Vernier-.- Hare/a 5. Foster,

,6 Mr? /As A6651" g United States I Patent Ofifice 3,032,851 Patented May 8, 1962 3 032,861 METHQD OF MANUFACTURING A FLATIRON Harold S. Foster, Ontario, Calif, assignor to General Electric Company, a corporation of New York Filed May 27, 1957, Ser. No. 661,974 4 Claims. (Cl. 29-1555 This invention relates to flatirons, and more particularly to a construction and method of manufacture of an improved flatiron.

Electrically heated flatirons typically have included a sheathed type electrical heating element embedded in a cast iron or cast aluminum soleplate. Casting techniques have been employed for manufacture of electrically heated soleplates for several reasons. In the first place, a relatively even heat distribution pattern is achieved at the ironing surface of the soleplate; and a relatively thick soleplate, inevitably resulting from casting techniques, is advantageous, since the completed iron does not then present any sharp or thin edges which might tear or damage fabrics being ironed.

While flatirons have been proposed previously formed with relatively thin sheet metal soleplates, the results have not been altogether satisfactory for several reasons. Non-uniform heat distribution pattern has always presented a diflicult problem. In my co-pending application Serial Number 661,973, filed May 27, 1957, assigned to the General Electric Company, assignee of this application, a practical construction is disclosed and claimed for securing the heating elements to such a thin soleplate with an excess quantity of heat conducting brazing metal, thus to overcome the problems of heat distribution. In accordance with this invention, a construction and method of manufacture is provided, directed toward the edge construction of the soleplate, and the cover which cooperates with the soleplate assembly to define the body of the iron.

It is, therefore, one object of my invention to provide an improved iron, which although includes a thin sheet metal soleplate, has the operating characteristics of a cast soleplate type iron. A further object of this invention is to provide a flatiron soleplate fabricated from relatively thin sheet metals, presenting, however, the advantages and appearance of an iron having a relatively thick cast soleplate.

Still another object of this invention is directed to the method of manufacture of a flatiron soleplate and cover therefor, to reduce manufacturing cost by greatly reducing the quantity of metallic material which is required.

In accordance with an illustrated embodiment of my invention, a relatively thin sheet metal soleplate is provided with an edge member extending angularly upwardly and inwardly from the soleplate. This edge memher, when bonded to the soleplate, presents the characteristics of a relatively thick cast soleplate. The upper portion of the edge member is formed to define a shoulder or seat to receive the iron cover, which extends over the entire soleplate and defines with the soleplate the body of the iron.

In accordance with another aspect of this invention, a method of manufacture is provided by which the soleplate and body of the iron are constructed with a minimum of materials. A soleplate blank of a size slightly larger than the finished iron is provided. An edge member and cover are drawn from a single sheet of metal, after which the edge member is sheared from the cover, with deformation of the sheared edges to define a mating seat and edge for the cover and the upper portion of the edge member. The edge member, having an over-all size approximately commensurate with the soleplate blank, is secured to the blank, for example, by brazing.

Thereafter, the outermost edges of the soleplate and edge member are simultaneously trimmed to size.

The subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. The invention, itself, however, both as to organization and method of manufacture, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawing in which:

FIG. 1 is a plan view of a soleplate assembly embodyin g this invention;

FIG. 2 is a partial cross-sectional elevation view of a flatiron embodying this invention;

FIG. 3 is an enlarged cross-sectional elevation view of components of this improved iron in an intermediate stage of manufacture;

FIG. 4 is an enlarged cross-sectional elevation view of a portion of this improved flatiron, illustrating a further stage of assembly and manufacture;

FIG. 5 is an enlarged cross-sectional elevation view illustrating still another step in the assembly and manufacture;

And FIG. 6 is an enlarged partial sectional elevation view to illustrate the final manufacturing step in providing this improved iron.

Referring now to the drawings, in FIGS. 1 and 2, I have shown an electrically heated soleplate assembly and a portion of the enclosing cover therefor. Soleplate 1 is formed of relatively thin sheet metal, for example, steel or stainless steel. A steel soleplate is preferred, since the material is readily available at relatively low cost, and it presents a hard ironing surface which can be polished to a high degree. If stainless steel is not employed,

a corrosion-resistant ironing surface can be provided byelectroplating in a well-known manner. Soleplate 1, being relatively thin, presents a relatively thin edge around the perimeter of the iron, which edge may tend to damage fabrics being ironed if great care is not used. To obviate this difficulty, an edge member 2 is secured to soleplate 1, extending upwardly from the soleplate and angularly inwardly, thus providing an edge contour similar in appearance and function to the relatively thick edge presented by a cast soleplate. In other words, the addition of edge member 2 provides an appearance of thickness to the soleplate, and eliminates the relatively thin peripheral edge, thus providing increased safety and efficiency in iron performance. As clearly shown by FIG. 2, edge member 2 is formed to define a seat or shoulder 3 to receive a cover 4. In a conventional manner, cover '4 extends over substantially the entire soleplate, and with the soleplate assembly defines the body of the iron.

Within the body of the iron, electrical heating elements, such as 5 and 6, are provided. As shown, two such heating elements are preferred in this type of fiatiron to assure relatively uniform heat distribution over the entire ironing surface. For safety and reliability, sheathed type heating elements are preferred, comprising an electrical resistance element 7, extending centrally through an outer protective sheath 8, with the heating element separated from the sheath by a mass 9 of electrical insulating material which is resistant to heat generated within the element. Such material 9 may be, for example, highly compressed granulated magnesium oxide. As shown, properly shaped heating elements may be secured initially in position on the soleplate by a plurality of clips, such clips 10, 11, and 12 being applied to outer heating element 6; While clips 13, 14, and 15 are similarly disposed with respect to heating element 5. As shown, these clips are spot-welded orotherwise suitably secured to soleplate 1. The soleplate is also provided with a boss 16 in a generally central position on the upper surface of the soleplate, to provide a mounting point for a thermally responsive switch assembly which controls energization of the heating elements. Additionally, a U-shaped bracket 17 with outwardly extending ears may be spot-welded to the soleplate to provide a securement point for cover 4 and for a handle (not shown).

In the series of views 3 through 6, the sequence of operations in manufacture of this improved flatiron is illustrated. Referring particularly to FIG. 3, a partial view of a formed blank 18 is shown, this blank being drawn or otherwise suitably formed from a single piece of sheet metal, to provide both the edge member 2 and cover 4. More particularly, the original blank 18 is of a size and shape generally commensurate with the blank for soleplate 1. Bottom flange 19 of this blank is intended to be placed in contact with the outer edge portions of the soleplate blank. To form edge member 2, an angular portion extending generally upwardly as at 20 is formed, with a seat or shoulder 3 depending inwardly from the upper end of portion 2d. The upper portion 21 of this blank is contoured to the desired shape for cover 4. In other words, blank 18 is so formed as to provide both the edge member and the cover of the iron. After it has been drawn or otherwise formed, the blank is placed in a trimming die, for example, of the type known as a Brehm die. This device accurately shears the edge member from the cover member, for example, along the line 2-2 shown in FIG. 3. Thereafter, that portion of blank 1% defining the edge member is deflected inwardly, as shown in dotted lines, thus completing formation of edge member 2. This inward deformation of the edge member also allows the lowermost edge of cover 4 to rest on flange 3 of the edge member in the manner shown by FIG. 2. Obviously, it would be equally feasible to deflect the cover portion 4 outwardly in order that its lowermost edge could rest on shoulder 3.

Following the completion of edge member 2, it is placed in position on soleplate blank 1, with the flange 19 in contact with the soleplate blank. With the components held in an appropriate jig for proper alignment, edge member 2 may be spot-welded or otherwise secured to the soleplate blank, such as indicated at weld mark 23 in FIG. 4. Typically, this spot-welding operation is performed at approximately the same time as the spotwelding of the various clips for the heating elements.

As disclosed and claimed in my aforementioned application Serial Number 6-6 1,973, the upper surface of soleplate 1 receives either an appropriate surface treatment, or is covered With a wire screen as shown at 24 in FIG. 1. While the use of a wire screen is shown in the drawing, it may also be feasible to score the upper surface of the soleplate in a pattern generally resembling that of the wire screen as shown. With all of the components spotwelded or otherwise temporarily secured in position as shown in FIG. 1, and as further shown in FIG. 4, brazing metal is applied to the upper surface of the soleplate. Since it is desirable to increase as much as possible heat transfer between heating elements and the soleplate, I prefer to employ a brazing metal which is a good heat transfer agent. Among the materials usable for this purpose, it has been found that electrolytically pure copper is quite satisfactory, since such material has a high co-eflicient of heat transfer. Typically, a measured quantity, for example, by weight, of copper globules are placed on the upper surface of the soleplate distributed over the screen or surface matrix 24. The entire assembly is then placed in a furnace and heated in a reducing atmosphere somewhat in excess of the melting temperature of the brazing metal. Thereupon, the brazing metal, supplied in excess quantity beyond that needed to secure the various components in assembled relation, melts and distributes in a layer of appreciable thickness over the entire upper surface of the soleplate. In addition, the

brazing metal flows into the angle of junction between edge member 2 and soleplate 1, as indicated at 25 in FIG. 5. As a practical matter, it is found that when using substantially pure copper, the molten copper quickly wets all exposed metallic surfaces, and by capillarity tends to rise along the walls of the edge member. The presence of the surface deformation on screen 24 becomes quite important in order to retain, also by capillarity, a substantial quantity of the brazing metal on the upper surface of the soleplate. The brazing metal securely bonds the edge member 2 to the soleplate in a manner as clearly illustrated by FIGS. 5 and 6.

Following completion of the brazing operation, the soleplate blank and attached edge member may be placed in a trimming die, whereupon the outer rough edges of both members 1 and 2 are sheared off, for example, along a line 226, as shown in FIG. 5. The remaining edge portion 27, shown in dotted lines in FIG. 6, is ground and polished in order to produce essentially the config uration illustrated in full lines in FIG. 6. Finally, the assembly is electroplated to produce the desired finish. Thus, in final appearance and in characteristics from an operating viewpoint, the finished soleplate and edge member assembly can hardly be distinguished, when cover 4 is in position, from an equivalent iron formed with a cast soleplate.

While this invention has been described by reference to a particular embodiment thereof, it is to be understood that numerous modifications may be made by those skilled in the art without actually departing from the invention. It is, therefore, the aim in the appended claims to cover all such equivalent variations as come within the true spirit and scope of the foregoing disclosure.

What I claim as new and desire to secure by Letters Patent of the United States is:

.1. The method of manufacturing a flatiron comprising forming a soleplate blank from a flat metallic sheet with the outer edges thereof extending beyond the edges of a finished soleplate, drawing a metal sheet to form a blank having sections forming an integral edge member and cover with said blank having an outer portion substantially co-extensive and contiguous with the outer edges of the upper surface of said soleplate blank, shearing said blank to separate the section forming said edge member from the section forming said cover and deforming relatively said sheared edges to form a seat on said edge member to receive said cover, securing temporarily said edge member and a heating element on said soleplate, brazing with an excess of metal to bond said edge member and said heating element to said soleplate, and thereafter trimming the outer edges of said soleplate blank and edge member to form the finished soleplate.

2. The method of manufacturing a flatiron comprising forming a soleplate. blank from a flat metallic sheet with the outer edges thereof extending beyond the edges of a finished soleplate, drawing a metal sheet to form a blank having sections forming an integral edge member and cover with said blank having an outer portion substantially co-extensive and contiguous with the outer edges of the upper surface of said soleplate blank, shearing said blank to separate the section forming said edge member from the section formingrsaid cover and deforming relatively said sheared edges to form a seat on said edge mem 7 her to receive said cover, securing temporarily said edge member on said soleplate, brazing with an excess of metal to bond said edge member to said soleplate, and thereafter trimming the outer edges of said soleplateblank and edge member to form the finished soleplate.

3. The method of manufacturing a flatiron comprising forming a soleplate blank from a flat metallic sheet with the outer edges thereof extending beyond the edges of a finished soleplate, drawing a metal sheet to form a blank having sections forming an integral edge member and cover member, saidblank having an outer portion subac, v

stantially co-extensive and contiguous with the outer edges of the upper surface of said soleplate blank, shearing said blank to separate the section forming said edge member from the section forming said cover member and deforming relatively said sheared edges to form a seat on one of said members to receive the edge of the other member, positioning said edge member temporarily on said soleplate, brazing said edge member to said soleplate, and thereafter trimming the outer edges of said soleplate blank and said edge member to form the finished soleplate.

4. The method of manufacturing a flatiron comprising forming a soleplate blank from a flat metallic sheet of a size slightly exceeding the size of the finished soleplate, drawing a metal sheet to form a blank having sections forming an integral edge member and cover member, said blank having an outer portion substantially co-extensive and contiguous with the outer edges of the upper surface of said soleplate blank, shearing said blank to separate the section thereof forming said edge member from the section thereof forming said cover member 6 and deforming relatively said sheared edges to form a seat on one of said members to receive the edge of the other of said members, securing said edge member to said soleplate continuously around the edge of said soleplate, and trimming the outer edges of said soleplate blank and edge member to form the finished soleplate.

References Cited in the file of this patent UNITED STATES PATENTS 1,009,390 Droitcour Nov. 21, 1911 1,130,077 Eldred Mar. 2, 1915 1,254,558 Zeitler Jan. 22, 1918 1,257,502 Leighton Feb. 26, 1918 2,005,234 McArdle June 18, 1935 2,049,089 Stackhouse July 28, 1936 2,257,451 Barnes Sept. 30, 1941 2,397,084 Bernhardt Mar. 26, 1946 2,706,766 Huffman Apr. 19, 1955 2,807,700 Jepson Sept. 24, 1957

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