US3800445A - Method and apparatus for making scuff slippers and the like - Google Patents

Abstract

An article of footwear is disclosed including an upper assembly having a midsole member with a laterally protruding peripheral ledge portion. The article is provided with a unitary outersole having an integral upwardly extending peripheral side wall portion overlying the outer periphery of the ledge and having at its outer end a peripheral inwardly projecting bead substantially surrounding the ledge on three sides. An injection molding method and apparatus for making the article are further disclosed. The apparatus includes a mold plate and preferably a pair of laterally movable rings each having an inwardly directed peripheral lip piece overhanging and engageable with the upper lateral surface of the ledge.

Description

United States Patent [1 1 Greenblatt et al.

[ METHOD AND APPARATUS FOR MAKING SCUFF SLIPPERS AND THE LIKE [76] Inventors: David Greenblatt, 135 Redwood Dr., Roslyn, N.Y. 11576; Allan Greenblatt, 5 Hickory Dr., Great Neck, N.Y. 11021 [22] Filed: June 1, 1971 [21] Appl. No.: 148,652

[ Apr. 2, 1974 Primary Examiner-Patrick D. Lawson Attorney, Agent, or FirmDarby & Darby [5 7 1 ABSTRACT An article of footwear is disclosed including an upper assembly having a midsole member with a laterally protruding peripheral ledge portion. The article is provided with a unitary outersole having an integral upwardly extending peripheral side wall portion overlying the outer periphery of the ledge and having at its outer end a peripheral inwardly projecting bead substantially surrounding the ledge on three sides. An injection molding method and apparatus for making the article are further disclosed. The apparatus includes a mold plate and preferably a pair of laterally movable rings each having an inwardly directed peripheral lip piece overhanging and engageable with the upper lateral surface of the ledge.

3 Claims, 5 Drawing Figures PATENTEHAPR 2mm 3.800.445

sum 1 or 2 VA W INVENTORS I A ID GREENBLATT AN GREENBLATT ATTORNEYS PATENTEDMR 2:914

SHEET 2 0F 2 INVENTOR. DAVID GREENBLATT ALLAN GREENBLATT ATTORNEYS METHOD AND APPARATUS FOR MAKING SCUFF SLIPPERS AND THE LIKE The invention relates to an article of footwear and to a method and apparatus for applying soles to articles of footwear, amd more particularly to footwear having an integral sole heel unit molded to scuff slippers and the like which may be used for indoor and outdoor casual wear, and to a method and apparatus for producing such footwear.

BACKGROUND OF THE INVENTION Scuff slippers are generally provided with a resilient sole portion of sufficient thickness to cushion the foot, and a fabric or fleece-like upper portion comfortably confining the foot above the sole portion and having an opening for the reception of the foot. Frequently, scuff slippers are of the open toe and open back type, although the present invention is not limited to any particular style.

It is customary that the fabric upper portion be assembled by sewing the lower edges of the fabric to the outer edges of a sole liner by means of a conventional overedge seaming operation. The fabric upper portion and sole liner is then secured to the outer sole portion by sewing or stitching to prevent their separation. Traditionally, the fabric upper portion is attached to an adjacent outer peripheral edge of the outer sole member by a row of sewn stitches extending around the periphery of the latter. Such stitching generally penetrates a protruding peripheral ledge of the outer sole. The resulting seam is normally somewhat unsightly and unaesthetic, and for a salable product must be'hidden. The prior type of scuff slipper therefore has been provided with a binding tape, frequently an elastic tape or band or the like, which is folded and attached over the overedge seam by yet another row of stitches.

Alternatively, the binding tape may be placed over the peripheral edge of the seam between the upper and the sole liner. In this arrangement, the assembled upper and its peripheral band is then stitched to the outer sole member.

These prior methods for producing slipper-type footwear have had certain attendant disadvantages which have been overcome by the present invention. For example, the prior methods employed a plurality of stitching operations, which required highly skilled and consequently costly labor. Such work is furthermore time-consuming, and significantly reduces productivity.

A further disadvantage of the prior method resides in the difficulty in achieving a consistent appearance from one shoe to another, owing to inadvertent irregularities in alignment of the shoe with the stitching machine. For example, the stitching in any one particular shoe may not be particularly straight, or the binding tape which is conventionally used to hide the overedge seaming operation may not" sufficiently cover such seam. Such occurrences may give rise toa high rejection percent age at quality control stations, thereby decreasing the manufacturers ability to meet commercial demands.

Still another disadvantage of the prior method, resides in the unavoidablewear and tear on the individual st'icheswhich secure the upper to the outer sole member. These stitches traditionally extend completely through the edges of the outer solememb'er so as to be exposed to contact of the bottom surface of the sole withabrasiveenvironmental surfaces. It has been found that such stitches are subject to being worn away and breaking, thereby releasing the upper from the sole member and rendering the shoe unusable before it is otherwise worn out.

In accordance with the present invention, a scuff slipper is provided having an insole or midsole which is both adhered to the outer sole, and locked to it by being surrounded at the edge on three sides by the outer sole. This provides a finished appearance without stitches and also serves to retain the insole and attached upper to the outsole.

This is accomplished by a special mold having a soleplate and preferably split side rings which move laterally into abutment with the edge of the soleplate to form a molding cavity which partially surrounds the insole to which the upper is secured. The mold ring has an inwardly turning hooked lip whose inner edge engages the top part of the insole near the latters peripheral edge, to provide means for molding the outer sole material not only beneath but also at the side and above the periphery of the insole. The pressure of subsequently injected bottom-forming composition forces the insole against this hooked lip to seal the mold cavity to the insole of the shoe at the upper side of the insole. A bead is thereby molded around the shoe at the top surface of the insole, as well as around the side of the insole, and covering the full bottom of the insole.

It is one object of the present invention to provide an open shoe scuff slipper having an outer sole molded thereon.

Another object of the present invention is to provide an open shoe scuff slipper in which the insole is locked to the outer sole by being surrounded at its peripheral edge on three sides by the latter.

Still another object of the present invention is to provide a method and apparatus for forming and attaching an outer sole to an open-shoe scuff slipper or the like without the need of stitching.

A further object of the present invention is to provide a method and apparatus for injection molding an outer sole to the insole of an open-shoe scuff slipper or the like.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention, reference may be had to the accompanying drawings, in which;

FIG. 1 is a perspective exploded view of a molding apparatus according to the present invention;

FIG. 2 is a cross sectional view taken along the line 2-2 of FIG. 1';

FIG. 3 is a fragmentary sectional view similar to the view of FIG. 2 showing the injection step completed;

FIG. 4 is aperspective view of an open-toe scuff slipper having an outer sole molded on in accordance with the present invention, and showing the outer sole partially cut away.

FIG. 5 is an elevation view taken in section along line 5-5 in FIG. 4.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, and in particular to FIG. 1, there is shown a mold assembly, generally indicated by referencenumeral 10, which consists of a soleplate 11 mounted on a suitable base member 12,

and ring means 13 which, together with soleplate 11, form a mold cavity for shaping an injected bottomforming composition. The ring means 13 is preferably longitudinally split along a median extending from the toe to the heel of the soleplate 11, to form cooperating substantially mirror halves or side molds 14 and 16. These split halves are actuated by conventional means (not shown) for movement toward one another and the sole plate to form the cavity, and movement apart to free the shoe after the outer sole is molded. It should be noted that, while the ring mold apparatus illustrated consists of the mirror halves 14 and 16, it is obvious that such ring mold could be made in additional parts or even could be one piece, as desired. The embodiment illustrated is merely the preferred form.

The soleplate 11 of the bottom mold component 12 is preferably a continuous surface for forming the tread face and shank portions of the sole, and that surface may be embossed, knurled, corrugated or otherwise fashioned to impart an ornamental or tread-like texture to the injected plastic material. The rear end of the soleplate l 1 may be shaped, as desired, to mold the sole with an integral heel of any desired height or shape, or to create a wedge sole. In the present illustrative embodiment, the soleplate 1 l is substantially flat throughout its entire length, thereby to mold a bottom sole member suitable for an open-shoe scuff slipper.

Each of the cooperating side molds l4 and 16 is provided with an overhanging lip 17 extending around its periphery, seen best in FIGS. 2 and 3. The lip 17 is preferably integral with its corresponding side mold, and may be substantially inwardly chamfered or beveled to terminate in a relatively sharp edge 25 (FIGS. 2 and 3). As illustrated in FIGS. 2 and 3, the lip 17 extends not only laterally inward relative to its side mold, but is curved somewhat back on itself and downwardly at its terminal edge, to form a hook-like or substantially inverted J-shaped cross-section.

The first step of the present process consists in securing a preformed upper assembly to a foot form or otherwise conventional type of last (not shown). In the present embodiment, this upper assembly preferably consists of a fleece-like upper portion secured to an inner sole or midsole 20, having a laterally protruding peripheral edge or ledge portion 20a, seen best in FIG. 3. The next step is to move the upper assembly relative to the mold apparatus such that the midsole 20 is positioned or placed upon or adjacent the soleplate ll of the bottom mold 12. It should be noted, that in accordance with the present invention, it is not essential, in connection with the open-shoe type of footwear, to apply the pre-formed upper assembly to a conventional last. It is sufficient that the upper assembly simply be' placed upon the soleplate 11.

In the next step of the process, the cooperating side molds l4 and are moved laterally inwardly to the position shown in broken lines in FIG. 2. In this position, lateral side wall portions 15 of .the side molds l4 and 16 are engaging corresponding sidewall portions 15a of the base member or bottom mold component 12.

The contraction of the cooperating side molds l4 and 16 against the bottom mold component 12 and around the edge a of the inner sole, serves to form the mold cavity. In the preferred embodiment, the downwardly curved lip 17 overhangs the peripheral ledge 20a of the inner sole 20, as shown in FIG. 3. It should be noted that the sole plate 1 l is wider than the inner sole 20 so as to leave space for the molding composition to flow as explained below.

Having thus prepared the mold cavity, th plastic bottom-forming composition is injected under pressure through an inlet 23 in the sole plate 11. As it flows into the mold cavity from beneath the inner sole 20, the bottom-forming composition presses upwardly against the underside of the inner sole, thereby forcing the upper lateral surface 22 of the inner sole against the terminal edge 24 of the lip 17 to form a suitable molding seal. The bottom-forming composition continues to flow into the mold cavity and is forced upwardly around the inner sole 20 under the lip 17 and consequently over the top of the inner sole ledge portion 20a. In this manner, a bead is molded around and adheres to the shoe at the top surface 22 of the insole, as well as around the side of the insole, and covering the full bottom of the insole to form an outsole 30. It will be understood, therefore, that the insole is not merely adhered to the plastic outer sole 30, but is locked into it by being surrounded at its peripheral edge on three sides by the plastic composition.

The injection step continues until the mold cavity is solidly filled. The injected compound is then held under appropriate known conditions of heat and pressure until fully cured. In this step, a bond is formed between all the assembled parts that normally will outlast the usual life of the shoe.

Several alternative techniques may be employed for removing the completed scuff slipper from the mold, without obstruction from the overhanging lip 17. One such suitable technique is merely to provide that the bottom mold 12 be movable downwardly so that the peripheral bead portion of the outer sole may be moved correspondingly downwardly away from the terminal edge of the lip 17. The cooperating side molds l4 and 16 may then be moved apart laterally to the positions shown in FIG. 2. The slipper is then removed from the last and may be trimmed where necessary to remove any mold flash or spew which may be produced in molds consisting of a base plate and separate cooperating side molds.

Where it is desirable to provide scuff-slipper-type footwear having a sole and heel made from a reasonably soft and easily deformable bottom-forming composition, the cooperating side molds l4 and 16 may be moved laterally without first lowering the bottom mold 12. Under such circumstances, the bottom composition will undergo a small degree of compression by the terminal edge of the lip 17. However, the footwear may be easily withdrawn from the mold without resultant damage. It should be noted that the curve of the overhanging welt portion 17 has been exaggerated in the illustrations, in order that a readily distinguishable edge may be seen, but it is to be understood that the radius of curvature of the lip must be determined with respect to the material chosen to form the outer sole. For example, if the material were too hard, any attempt to extract the completed footwear without first lowering the bottom mold 12 would result in the outer sole being damaged, if not torn completely away from the inner sole 20.

A plastic compound well suited for the described process is polyvinyl chloride, often referred to as PVC, and this may be plasticized to a desired degree to develop a more or less rubbery texture. The present process is not, however, limited to use of PVC, but may be carried out with other vinyl or synthetic compounds having equivalent or similar properties.

In FIG. 4 is illustrated a scuff slipper according to this invention, having an injected molded bottom 30. In accordance with the present invention, the bottom 30 is provided with a tread surface 24 and an integral peripheral bead portion 26 extending upwardly around the edge of the inner sole and sealed to the latter on its lateral upper surface 22. The molded outer sole is illustratively shown secured to an open-shoe scuff slipper having an open-toe fleece portion 27 which is connected to the inner sole 20. The injected molded shoe bottom 30 of the present invention is particularly suitable for this type of footwear, in that the inner sole 20 has an exposed lateral portion or ledge 20a which may be engaged by the surrounding bead 26 of the molded outer sole.

It should be noted however that the molded sole of the present invention is not to be limited in its application to open-shoe scuff-slippers as depicted in FIG. 4. It is the outer ledge 20a of the inner sole 20 which is gripped by the bead portion 26, and accordingly the invention may be practised upon any form of shoe upper having a suitable outer or peripheral ledge. Open-shoe scuff slippers are particularly suitable, but are intended to be merely illustrative.

What is claimed is:

1. An article of footwear comprising:

an upper piece;

a substantially planar insole piece connected to said upper piece at points inwardly of the edge of the insole to define a peripheral bonding ledge on said insole; and

a one-piece bottom bonded to said insole piece, said bottom having an outsole portion integral with an upwardly extending peripheral side wall portion overlying the outer periphery of said ledge and having at its outer end a peripheral inwardly projecting bead overlying and bonded solely to the surfaces of said ledge, to substantially surround said ledge on three sides, thereby to lock said bottom to said insole.

2. An article as in claim 1 wherein said bottom is of substantially uniform thickness.

3. In combination, an upper piece for a shoe, a substantially planar midsole piece having a peripheral ledge portion, a one-piece injected molded shoe bottom attached to said midsole piece and comprising a sole portion forming the entire tread surface of the shoe bottom and being of substantially uniform thickness, said bottom having an upwardly extending peripheral sidewall portion overlying and bonded solely to substantially three surfaces of said ledge portion.

Claims (3)

1. An article of footwear comprising: an upper piece; a substantially planar insole piece connected to said upper piece at points inwardly of the edge of the insole to define a peripheral bonding ledge on said insole; and a one-piece bottom bonded to said insole piece, said bottom having an outsole portion integral with an upwardly extending peripheral side wall portion overlying the outer periphery of said ledge and having at its outer end a peripheral inwardly projecting bead overlying and bonded solely to the surfaces of said ledge, to substantially surround said ledge on three sides, thereby to lock said bottom to said insole.

2. An article as in claim 1 wherein said bottom is of substantially uniform thickness.

3. In combination, an upper piece for a shoe, a substantially planar midsole piece having a peripheral ledge portion, a one-piece injected molded shoe bottom attached to said midsole piece and comprising a sole portion forming the entire tread surface of the shoe bottom and being of substantially uniform thickness, said bottom having an upwardly extending peripheral sidewall portion overlying and bonded solely to substantially three surfaces of said ledge portion.

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