US2403950A

US2403950A - Shank stiffener

Info

Publication number: US2403950A
Application number: US580191A
Authority: US
Inventors: Rosenthal Nathan
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-02-28
Filing date: 1945-02-28
Publication date: 1946-07-16
Anticipated expiration: 1963-07-16

Description

July 16,'1946. N. Rosi-:NTHAL sHANK 'STIFFENER Filed Feb. 28, 1945 Patented July 16, 1946 UNITED STATES PATENT oFI-ICE 2 Claims.

My present invention is a novel and improved shank stiffener for use in the manufacture of boots and shoes, and is directed particularly to provide a shank stiffening and arch-supporting feature with special reinforcements in the archsupporting portion of the shoe.

Heretofore, it has been customary to make shank stiffeners of metal which would be tted between the insole and outsole and Would give a stiffening and reinforcing effect in the arch of the shoe between the heel and the tread portion of the forepart. Such metal stiffeners were usually .secured to the heel and extended forwardly in a preformed curve to a sliding engagement at the ball or forward portion of the outsole.

`It has also been customary to have one or more longitudinal corrugations or ribs formed in a part of the shank stiffener to aid in holding the arch of the shoe in predetermined arc-shape.

My present improved arch stiffener constitutes a double reinforcing structure wherein a :part of the arch stiifener comprises a strengthening and reinforcing element longitudinally from the heel to the ball of the shoe, and a second preformed portion with a distinct disaligned arc structure in the shank stiffener which will automatically effect a supporting and lifting of the lateral or side portion of the arch of the shoe and, hence, constitute a support for the side arch portion of the foot of the wearer.

Furthermore, I so arrange and construct my present improved shank stiffener as to provide a reinforcing rib member in a curved formation, defining the area lbetweenthe fore and aft arch and the lateral supporting feature. In order to secure additional rigidity in the lateral supporting feature, I provide one or more ribs therein, which ribs may be and preferably are of curved contour and may be either longitudinally or crosswise of the length of the stiffener. In either case, the side or lateral arc portion of the shank stiffener gives a vastly greater and increased lateral arch support to the sole of the shoe in which the stiffener is fitted, as well as to the foot of the wearer, giving a firm support and brace to the lateral arch of the shoe.

Thus, my present stiifener comprises a double reinforcing shoe shank stiffener, having one arc formation for the longitudinal or fore and aft structure of the shoe, and a divergent and different lateral arched contour with reinforcements therein for the side or lateral arch of the shoe and foot. Thus, my shank stiffener constitutes a reinforcing element from the heel to the forepart, and also a side or lateral arch-supporting element at a dierent and much sharper angle, predetermining the contour and form of the shoe and insole at this lateral arch part and, hence, affording support to the foot of the wearer. Thus, my improved shank stiffener has inherent and added streng-th by reason of the divergent arched areas of the longitudinal and the lateral portions, the line of juncture between the lateral and the longitudinal differing arc formations constituting i-tself a truss-like effect or rib which, furthermore, will preferably have a distinct rib formation to predetermine the line of demarcation between the lateral and lengthwise arch and thus constitute a common supporting element for both the longitudinal and lateral arch portions.

Furthermore, by having the lateral arch of less length than that of the lengthwise arch portion, I secure the benefit of a full support at the heel and on the ball of the forepart of the shoe for the lengthwise strengthening part, these being fully equivalent to standard arch supports as at present in use.-

Furthermore, by having one or more reinforcing rib structures in the lateral arch itself, greater strength is added and the predetermined contour of the shoe itself is permanently maintained.

Referring to 'the drawings illustrating preferred embodiments:

Fig. 1 is a plan View of my improved shank stiffener Vwith the longitudinal and transverse arc-supporting structure;

Fig. 2 is a corresponding plan view illustrating reinforcing and stiffening convolutions;

Fig. 3 is a plan view illustrating a modification of reinforcing convolutions;

Fig. 4 is a side View of the shank stiffener of Fig. 1 showing the longitudinal arc contour, and

Fig. 5 is a diagrammatic view on the line 5-5 of Fig. 1 illustrating the shank stiffener as applied to the insole on a last illustrating the transverse arc feature.

My shank stiifener may be and preferably is made of metal stamped into longitudinal and transverse arccurves, which may be varied for the particular style, design, and size of shoe to which my shank stiffeners are to be fitted. The shank stiffeners as shoWn in the drawings are illustrative of a moderate arc contour both longitudinally and transversely, which arcs can be greatly increased where desired.

Referring to Fig. 1, the arch stiifener comprises a metal plate l of appropriate length and contour and, preferably, stamped from sheet material having a heel-engaging portion 2 and an opposite edge portion 3 to engage the ball of the shoe sole, which portion 3 may beand preferably is somewhat larger than the heel part, with a predetermined longitudinal curve from the heel part 2 lengthwise throughout a substantial widthwise area of the shank stiiener to the forepart 3. Holes 5 to enable the shank stiffener to be nailed rmly to the heel of the shoe are provided, and the forepart 3 is preferably unattached and is allowed to slide slightly to adjust itself to the contour of the sole and insole during use and to aid in the flexibility of the shoe at the ball portion. The transverse or widthwise arc is preferably formed on the blank during the original stamping-out action, or it may be shaped and curved afterwards, and consists in the transverse arc-shaped area I!) throughout a substantial extent of the length of the shank stiffener.

As shown in Fig. l, this transverse area IU may be stamped from where the heel part of the shank stiffener extends over the heel breast of the shoe, as indicated approximately at I2, Fig. 1, extending to the extreme forepart of the edge 3, as shown at I3, and merging into the longitudinal arc portion of the shank stiifener I on a curved line, as approximately indicated at I5, which curved line may be also formed as a stiiening convolution or rib.

This rib I5 thus acts jointly to hold both the longitudinal arc of the main part of the stiffener I in its preformed position as well as serving to stiffen and hold the transverse arc portion IIJ in its preformed position.

My improved shank stiffeners are made for rights and lefts with the transverse arc portion ID adapted to lift the insole and, hence, support the foot of the wearer on the inner transverse arch portion of the shoe and foot, thereby affording a snugger fitting and hugging of the foot, which also facilitates the lasting operation, enabling the shoe upper materials to be drawn down smoother and firmer during lasting,

In Fig. 2 I have shown a plurality of reinforce ing ribs or convolutions to still further hold and maintain both the longitudinal and transverse a;

arc-shaped portions of the shank stiffener in their predetermined curved position The longitudinal rib 20 aids in holding the longitudinal arc while one or more transverse ribs 2`I, 22, and 23 hold the transverse arc portion IU in reinforced preformed contour.

Additional ribs

23 and 24 may be also stamped or otherwise formed in the blank during the manufacturing operations.

In Fig. 3 I have illustrated a single lengthwise curved reinforced convolution or rib 25, and various modifications of such reinforcing element will readily occur to those skilled in this art, the important characteristic of my longitudinal transverse arch formation being thus maintained to hold the shoe in exactly the shape and supporting contour for which it is designed.

As shown in Fig. 5, my shank stiifener is illustrated as applied to an insole 30 between the sewing ribs 3I and 32, which insole is illustrated as positioned on a last 35, the last having a complemental cut-away portion 36 to cooperate with the lateral arc-shaped edge I0 of my improved shank stiiener. This construction enables the foot-supporting portion of the insole to be precurved widthwise and to aid in merging the corresponding part of the insole with the uplifting adjacent part of the upper materials (not shown).

My shank stiffener may be applied to the insole before it is fitted to the last or may be applied afterward but before lasting so as to thus impart to the insole the initial foot-supporting feature at the arch of the shoe and, hence, of the foot of the wearer.

My improved shank stiffener is entirely within the inner side of the sewing ribs of the insole and shoe and, hence, takes the place of the ordinary metal shank stiffener; but in my present improved construction, I provide one or more stiiening elements, such as ribbed convolutions in the laterally curved part of the shank stiifener, as distinguished from the longitudinally curved portion and any longitudinal ribbed strengthening elements. I believe it to be a distinct novelty in this art to have stiiening elements in the laterally curved or concavo-convex side portion, whether such ribbed strengthening elements are longitudinally curved or crosswise.

I claim:

l. A metal shank stiifener of the kind described, comprising a longitudinally curved portion and a laterally extending concavo-convex side portion, said side portion being formed in a divergent line or curve from the longitudinal curve, the side portion being reinforced.

2. A metal shank stiiener of the kind described, comprising a longitudinally curved portion and a laterally extending concavo-convex side portion, said side portion being formed in a divergent line or curve from the longitudinal curve, the side portion being reinforced by ribbed convolutions extending crosswise of the said side portion.

NATHAN ROSENTHAL.