US1963396A - Shoe shank stiffener - Google Patents

Description

June 19, 1934.

R. B. BARTELS SHOE SHANK STIFFENER Original Filed May 8, 1929 Patented June 19, 1934 UNITED STATES PATENT OFFICE SHOE SHANK Reinhard B. Bartels,

STIFFENER Marblehead, Mass.

1931, Serial No. 539,499

5 Claims.

Heretofore it has been customary to make metallic shank stiffeners for shoes, when the stiffeners are provided with integral attaching prongs, by cutting them from strip stock of the width oi" 5 the stiffeners. The attaching prongs, more particularly those of substantial length which must be bent to securely clinch when they are driven into the sole member as at the forward ends of stiifeners for welt or McKay shoes, are cut lengthwise of the strip so that they bend crosswise of the grain of the metal which is produced when it is rolled into sheet form. The narrow width stock is, however, more expensive weight for Weight than wider lstrip stock, since more operations are required to reduce it to a narrow condition. If, however, it be attempted to out this same form of stiffener widthwise from a relatively wide strip, not only is there considerable waste at the edge or edges where the prongs are formed, but these prongs extend across the grain of the metal and are much less able to withstand bending in the clinching operation without breaking. If, in order to overcome this liability to breakage of the prongs, a relatively soft metal is use, this is considerably more expensive than the harder metal, as it must be subjected to annealing, and further, a greater weight of such softer metal is necessary for the saine degree of stiffness of the stiifener. If these relatively long prongs are cut from the body of the stiffener widthwise so that they may be bent across the metal grain, so much of the metal is cut away that the stiffener is liable to break off at the prongs. These drawbacks to the use of Wide stock have therefore heretofore prevented its use for the manufacture of integral pronged stiffeners.

This invention has for an object the production of a pronged stiflener which is particularly suitable for cutting widthwise from wide strip stock and wherein the long prongs bend across the grain when being clinched, but which are so constructed that the stiifener is not unduly weakened where the prongs are formed. To this end, each prong is cut from the stock of two adjacent r side by side stiifener portions of the strip so that each prong may be of a length equal to onehalf the Width of the stiffener and yet leave onehalf of the width of the stifener at the prongs uncut. Not only does this construction make possible the cutting of the stiffeners widthwise, but in the case of a stiffener provided with a central longitudinal stiflening rib formed by a lateral bending of the stiffener, it makes possible the successful use of stock harder and less expensive than heretofore required for lengthwise cut stiffeners, since in the lengthwise cut stiffeners the rib is formed by bending the metal with the grain, which is likely to cause cracking if the harder stock is used, while in the cross cut stifl'enersthis l. rib is formed by bending across the grain.

The present application covers `the stiffener per se, the method by which it is formed being claimed in my Letters Patent No. 1,829,496 for Method of manufacturing shoe shank stiffener's, issued October 27, 1931, and from which the subject matter of this application has been divided.

For a more complete understanding of thisinvention, reference may be had to the accompanying drawing in which l Figure 1 is a side elevation of a finished stiffener.

Figure 2 is a cross section on line 2-2 of Figure l.

Figure 3 is a perspective of the wide sheet showing successive stages of the cutting and forming of stiffeners therefrom.

Figure 4 is a fragmentary plan of one portion of a strip showing one arrangement of the prongs.

Figure 5 is a detail section on line 5-5 of Figure 4. v i l Figure 6 is a fragmentary plan showing a different arrangement of the prongs.

Figures 'l and 8 are detail sections on lines 7-7 and 8 8, respectively, of Figure 5.

Referring to the drawing, at 1 is indicated a strip of sheet metal from which the stiffeners are to be cut. This strip is passed between suitable dies, as shown in my parent application hereinbefore mentioned, by which various cutting and l bending operations are successively performed 9o thereon. In the rst operation, prongs 11 are struck from one edge portion of the stock Aof the strip extending lengthwise thereof. At the same time prongs such as 12 may be struck inwardly near the opposite edge of the stock strip opposite 9 to the spaces between the prongs 11. .Next prongs 15 from stock lapping the stock cut to form the prongs 11, but extending in the opposite direction, are cut and the stock for the severalA stiffeners may be partially severed as by the slits 17. The prongs 11 and 15 are thus formed at the extreme end of each completed stifener. 'Ihe slits 17 are made opposite to the central portions of the side lapping lengths of material from which the prongs 11 and 15 are formed. The'1'05 partly severed stiffeners may then have stiffening ribs 18 molded therein and thereafter they may be molded to lateral curvature and then individually completely severed from the strip in com-.1 pleted condition. 110

The prongs l1 and 15 can be cut as shown in Figures 4 or 5, all the diagonal lines of severance 30 between the portions struck out extending in parallel relation. When the stiffeners are so cut the points of the prongs are offset from each other lengthwise of the stiffener, as shown in Figure 5, each stiffener having its prongs 11 and 15 arranged in the same relation theretofas all the others. Instead of so cutting the prongs, the diagonal cuts may be alternately reversely positioned as shown at 30 and 31 in Figure 6. In this case both prongs of each stiffener come opposite to each other lengthwise of the stifener, but those of one stiffener have their diagonal edges facing outwardly toward the adjacent end of the stiifen-` ers as shown at 32 in Figure 7 and the stiffeners cut from the strip portions next adjacent thereto have the diagonal sides of the prongs inwardly facing as at 33 in Figure 8. In both cases, however, it will be noted that one-half thelength of each prong is cut from the stock of the next adjacent strip portion thereto, so that these prongs maybe made each of a length of one-half the width of the strip portion and yet between the opposed prongs of each strip portion there is left an uncut space equal in width to the length of each of the long prongs and so equal in length to one-half the width of the completed stiffener. The combined lengths of the prongs and the body portion therebetween is thus substantially one and one-half times the maximum width of the Abody portion of the stiffener, the length of each prong being substantially one-half of this maxi.

mum width and the prongs being spaced apart one-half of this width. Moreover, as the grain of the metal runs lengthwise of the strip i, the line of bending of each of these prongs is transverse to theline of this grain so that the prongs can be bent, when the stifener is fixed to the sole member by clinching the prongs over, without danger vof breakage. These relatively long prongs should be placed at the forward ends of the stiffeners which are to be used for welt or McKay shoes. The rear end fastening means for the stiffeners is not required to be so secure, since this portion comes over the heel and is securely xed by the neighboring portions of Vthe shoe. v A relatively short prong which it is not necessary to clinch in the material istherefore allthat is necessary. These short prongsV may be formedl in 'various ways, therefore, Figures 6 and 'I' showing a Adifferent formfrom that illustrated in Figure 1. Referring to these Figures, it will be seen that the material of the stiffener is struck out at 35 in opposite directions to form pairs of short prongs 36.

I Each of the completed stiffener members, it will be seen, comprises a laterally extending strip section 51 cut from the relatively wide strip l,

' and has a centrally depressed reinforcing rib '18,

a pair of spaced relatively long integral attaching prongs 11 and 15 at one end bent from portions of greater width than the body portion of the stiiener and relatively short integral attaching prongs as 12 adjacent to its opposite end. If it were attempted to strike the long prongs from the material of the width of one individual strip portion there would be insuicient material to make these prongs of the necessary length. As the strip material 1 as commercially made varies slightly in width. it should be fed into the die pressed 'against the left hand edge as viewed in Figure 3, so that the prongs l1 and l5 may all be of full size. The prongs atthe opposite end of the stiffener being formed slightly inward from the end of the stiffener andl inwardly from the edge of the strip 1 are therefore not affected by the slight commercial variations in width of the strip 1.

From the foregoing description of certain embodiments of the stiffener together with a method and means by which such stiifeners may be formed, it should be evident to those skilled in the art that various changes and modifications might be made therein without Ydepartingv from the spirit or scope of this invention as defined by the appended claims. Y

I claim:

l. A shank stiffener having a body portion,

and opposed pairs of attaching prongs integral with said body portion and spaced apart substantially one-half the width of said body portion, each of said prongs being of'a length substantiaily one-half the width of said body portion and at the extreme end of said stiffener.

2. A sheet metal shank stiffener havingY the grain of the metal extending laterally thereof, and provided with` integral attaching prongs 'extending lengthwise of said grain at one extreme i end.

3. A shank stiifener having a body portion arranged with the grain of the metal extending laterally thereof, and having attaching prongs extending from the sidesv Vof said body portion at one end, the 4Vcombined lengths of said prongs and the body portion therebetween being greater than the width of said body portion.

4. A shank stiflener having a body portion arranged with the grain of the metal extending laterally thereof, and having attaching prongs extending from the sides of said body portion at one end, the combined lengths ofr said prongs and the body portion therebetween being greater than the width of said body portion, said stiifener also having attaching prongs inwardly of its opposite end. y f

5. A shank stifener having a body portion arranged with the grain of the metaly extending Ylaterally thereof, and having attaching prongsVVVV

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