US2433135A

US2433135A - Rubber footwear with front pull tab

Info

Publication number: US2433135A
Application number: US570614A
Authority: US
Inventors: Malm Henry
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-12-30
Filing date: 1944-12-30
Publication date: 1947-12-23
Anticipated expiration: 1964-12-23

Description

ec, 23, 1947. H. MALM 'j 2,433,135

. RUBBER FOOTWEAR WITH FRONT PULLv TAB Filed Dec. 50, 1944 M 40 20 wij/9 2 @Z4 25 5 55 INVENTOR ATToR Patented Dec. 23, 1947 RUBBER FOOTWEAR WITH FRONT PULL TAB gHenryiMalm, New YYork, N. Y,

ApplieationDecemherS, 1944, SerialNo. 570,614

2 Claims. (Cl. 36-74) This invention relates to rubber footwear in` the form of a back strap rubber comprising a main body portion engaging a front portion, sole and instep of the wearer with a strap member extending from the sides of the front portion around the back of a shoe to aid in supporting the rubber in position.

More particularly, the invention deals with a novel rubber of the kind deiined from a single molded all rubber body so that the resulting rubber will be adapted to fit variations in sizes and shapes of footwear and, further, in providing a pair of rubbers which can be compactly folded together to occupy a minimum amount of space in carrying the same about when not in use.

The novel features of the invention will be best understood from the following description when taken together with the accompanying drawing, in which certain embodiments of the invention are disclosed and, in which, the separate parts are designated by suitable reference characters in each of the views and in which:

Fig. 1 is a longitudinal sectional View through a mold indicating the method of forming a rubber therein.

Fig. 2 is a section on the line 2--2 of Fig. l.

F'ig. 3 is a section on the line 3 3 of Fig. 1.

Fig. Liis a perspective view of the core member of the mold detached', showing the rubber there. on; and

Fig. 5 is a plan view of the front toe portion of a rubber made according to my invention.

In Figs. 1-3 inclusive, I have shown at lil a bottorn mold part, at Il` a top mold part and, at I2, a core part. The core part I2 has, at the heel portion thereof, a transverse recess I3. The mold part Il] has corresponding recesses I4 and I5 in registering alinement with the recess i3. and all' adapted to receive a key member I6 on the top mold part II for alining said parts one upon the other.

fihemoldparts I il and I-I, aside from the recesses I 4, I5 and key member t6, have a parting' line defined by an inclined portion H arranged at one end'of the mold parts and shown at the left of Fig. 1. A center curved line I8 extends from the inclinedline Il to a straight and horizontally flat partingline i3 at the other end of the mold parts and shown at the right of Fig. 1.

rihe mold vpart ill has an impressionorcavity 20 which receives the major portion of the, coreA I2. 'Ivhe core I2 is'in the form of a last and has a toe portion 2i arch 22 and heel portion 23.

The last- 2i has a iiat surfacer extending from the upper part of the toe portion of the last to the 2 heel portion and bounded by side walls 25 which define the contour o the sides of the rubber including` the back or strap portion thereof, as later described. The walls 25 extend to a heel defining line 26, note Fig. 1, formed by enlargement of the heel portion 23 and arch portion 22. The last 2l also includes a fiat sole portion 21 which forms the inner surface of the sole in the resulting rubber.

The flat surface 24 of the last or core 2l is adapted to seat on a surface 28 of the cavity 22 in such manner as to space the core or last 2l from` the walls of the cavity 23, as well as from the wall portion 29 of the cavity 30 formed in the mold I I, the Wall portion 29 forming the bottom or outer surface of thel sole in the resulting rubber and having a roughened contour to provide on the resultingv rubber a roughV tread surface, as clearly seen on the sole 3l of the molded rubber, as illustrated in Figs. 1, 2 and 3 of the drawing.

The cavity 3U of the mold II also includes a curved wall portion 32 which forms the lower portionandthe sides of theshank orfarch portion 33 of the resulting rubber. The cavity 32, in alinement with the edge 26 of the core ZI, has a recess to form at the edge of the sole portion of the rubber an enlargement or bead 34. In this connection, the cavity 20 isalso similarly formed to extend this bead onto the strap portion 35 of the rubber, as seen at 36. The cavity 20 is also recessed around the surface 2B to form a corresponding enlarged or beaded edge 31 around the top of the rubber including the upper edge of the strap 35. The cavity 29 also includes a deep recess `centrally with respect to one end of the wall 28, as seen at 38, to form on the resulting rubber a ngerpiece or pull-tab 33.

It is also preferred that the cavity 2&1, or that part thereof which forms the upper and side surfaces of the toe portion 4I) of the resulting rubber, be recessed sufficiently to form thickened laterally extending wing portions 4I extending from the toe to the wide side portions of the rubber, as clearly indicated in Figj of the drawing to give to the rubber added body and wearing surface. The cavity 23 is also fashioned to form a slightly thicker and substantially arrow-shaped upper central'toe portion 42, note Fig. 5, which extends from the pull-tab 39 to the `wings tl.

The pull-tab 39 is employed to assist in drawing the rubber onto the toe portion of a shoe and, in this operation, the strain will be taken up through the reinforcement l2 and the thickened reinforcing or guard portion 4 I, while, at the same time, leaving a relatively thin body portion 43 on` the remainder of the toe and shank and in the strap 35.

It will appear from a consideration of Fig. 1 of the drawing that the thickest portion of the rubber is in the sole 3l which constitutes the only tread of the rubber, as the rubber does not include a heel portion or any other surface which will directly contact the ground in walking thereover.

The

beaded edges

34, 38 and 31 reinforces the peripheral edges of the rubber to prevent tearing and also to give strength to the elastic back strap portion 35. As previously stated, the footwear is entirely compo-sed of a molded all rubber body having no members retarding or checking free expansion of the footwear, thus it will be apparent that the footwear which is adapted primarily for use by women can be made up in two or three sizes and these sizes will fit practically all requirements in the ability of each size to expand itself sufficiently to take up intermediate sizes, as well as variations in the shape and contour of the shoe upon which the rubber is mounted.

Along the parting line of the molds, at the toe and shank portion thereof and outwardly ef the cavity is formed a groove 1M, note Figs. 1 and 2, the purpose of which is totake any overflow of material in the molding and vulcanization of the rubber. This forms a flare, which is afterwards trimmed off.

From the foregoing, it will be apparent that with my improved back strap rubbers, the entire upper portion of the toe and the major portion of the sides and the complete back strap is formed in the cavity of the die or mold I; whereas the sole and shank portion of the rubber is made in the cavity of the die or mold Il. It will thus be apparent that, after the rubber has been formed, upon removing the mold li, the core l2 with the rubber thereon can be lifted from the cavity of the mold Il by first raising upwardly on the toe portion and then pulling the core out of the cavity by movement slightly to the left, as seen in Fig. 1 of the drawing.

Considering Fig. 3 of the drawing, it will be apparentl that by forming the

side walls

45 and 46 of the cavity 2li tapered or flared outwardly to the back strap portion thereof, this removal of the core with the rubber thereon is facilitated. The cross-section of the mold is otherwise generally rounded, as will appear, for example, in Fig. 2 of the drawing.

The tapering of the walls 45 and i6 also produces a desirable result in the finished rubber in maintaining the upper beaded edge 31 in closer relationship than the lower beaded edges 35. This will produce a better iit of the strap upon the shoe and also keep the side portions of the rubber in firm engagement with the shoe.

From a consideration of Fig. 1 of the drawing, it will be apparent that the back strap of the resulting footwear is molded in an upwardly and rearwardly extended position with respect to the flat lower surface of the sole of the footwear or, in other words, in a form substantially the same as the footwear will be arranged upon a wcman's shoe. It will also be apparent from a consideration of Fig. 1 that the shank portion 33 is molded in close proximity to the toe portion All and in what might be termed e, high arch, the purpose of which is to adapt the rubber footwear for use on high heel shoes as well as lower heeled shoes, endeavoring to maintain, at all times, firm mounting between the top and sides of the toe portion and the shank by the freely flexing and 4 relatively high extensibility of the material molded in the rubber.

All rubber footwear of the kind under consideration is adapted for extension in all directions. In other words, the area of the sole 3l can be enlarged in all directions. The height of the toe with respect to the sole can be increased or decreased. These increases are all within practical limits to care for three or four sizes. While extensive stretching of a rubber of this kind is possible, this is undersirable as it fatigues the rubber and, further, applies undesirable pressure upon the foot; of the wearer.

In carrying out my novel method, I employ a novel die structure wherein the core, in conjunction with the one mold part, completely forms the back strap 0f the rubber. This is accomplished by providing the heel portion 23 on the core which, for the most part, is arranged in the mold l0 and is slotted to receive the key .member I6. This novel mold structure, in addition to providing the desired contour to the molded product, also facilitates the removal of the core from the cavity of the mold l0.

Having fully described my invention, what I claim as new and desire to secure by Letters Pa"- ent is:

1. In footwear, a rubber for mounting upon the shoe of a wearer, said rubber comprising a unitary molded body composed only of freely flexing relatively extensible rubber throughout, said rubber body comprising a toe and sole portion, shank and side portions rearwardly of the toe and sole portion, a back strap loop extending from said side portions upwardly and angularly to the sole portion of the rubber, the toe having thickened front and sides extending to the wide part of the toe portion of the footwear and spaced with respect to the upper edge of the footwear, another thickened portion extending from the thickened toe to the upper edge of the footwear centrally of the front portion thereof, said last named thickened portion terminating in an upwardly and outwardly extending pull tab at said upper edge whereby a pull on said tab is reinforced to the toe portion of the shoe.

2. In footwear, a rubber for mounting upon the shoe of a wearer, said rubber comprising a unitary molded body composed only of freely flexing relatively extensible rubber throughout, said rubber body comprising a toe and sole portion, shank and side portions rearwardly of the toe and sole portion, a back strap loop extending from said side portions upwardly and angularly to the sole portion of the rubber, the toe having thickened front and sides extending to the wide part of the toe portion of the footwear and spaced with respect te the upper edge of the footwear, another thickened portion extending from the thickened toe to the upper edge of the footwear centrally of the front portion thereof, said last named thickened portion terminating in an upwardly and outwardly extending pull tab at said upper edge whereby a pull on said tab is reinforced to the toe portion of the shoe, said second named thickened portion where it joins the pull tab being of a width common to the pull tab, and the second named thickened portion joining the first named thickened portion in a wide part extending the reinforcemet to the side portions 0f the toe.

HENRY MALM.

(References on following page) REFERENCES CITED The following references are of record in the le of this patent:

Number UNITED STATES PATENTS Name Date Tufts Apr. 13, 1880 Goodyear Dec. 19, 1916 Braselton Nov. 4, 1919 Morrill Feb, 22, 1921 Guinzburg Apr. 22, 1924 Joseph May 13, 1926 Roberts Dec. 28, 1926 De NoronhaJ Sept. 6, 1927 Valentini Oct. 25, 1927 Number Number Name Date Binder Oct. 1, 1929 Howland Feb. 11, 1930 Marguls June 9, 1931 Walker Sept. 15, 1931 Holler Sept. 29, 1931 Malm Jan. 15, 1935 Malm Jan. 19, 1937 Malm J an. 19, 1937 De Noronha Oct. 7, 1941 FOREIGN PATENTS Country Date France Oct. 26, 1925