METHOD OF MANUFACTURING AN ITEM OF FOOTWEAR AND FOOTWEAR ITEM MANUFACTURED THEREBY

Abstract: Item of footwear and its method of making wherein an inner sole (2) is assembled within an outer sole (1) having upturned peripheral edges (1a) receiving the inner sole (2) with peripheral portions of an upper portion (3) fitting between the upturned peripheral edge (1a) and the inner sole (2). The outer sole (1), inner sole (2), and upper portion (3) are each formed at least partially of a thermoplastic material at adjoining surfaces and these adjoining surfaces are sealed together to unify the shoe in a heat-sealing step.

Description: I METH O D OF MANUFACTURING AN ITEM OF FOOTWEAR AND FOOTWEAR ITEM MANUFACTURED THEREBY The present invention relates to the manufacture of items of footwear such as slippers, shoes, sneakers, boots, and the like by techniques which may be easily automated, and the items of footwear manufactured by such techniques. The manufacture of footwear typically requires a large number of steps, and many of these steps must often be carried out by hand. Accordingly, the labor costs associated with manufacturing various items of footwear can often be considerable. Additionally, manufacturing steps carried out by hand are always subject to human errors which can degrade the product. Further, the costs per unit of footwear depend largely on the number of steps in the manufacturing process, and the number of items of footwear that can be produced during a production run. It is, therefore, an object of the present invention to reduce the labor costs and increase the quality for the manufacture of footwear by providing a manufacturing technique which can be automated to an extent greater then conventional techniques for manufacturing footwear. It is a further object of the present invention to provide a process for the manufacture of footwear which has a minimal number of steps to not only simplify the manufacturing process, but also to provide a process that can produce more items of. footwear per unit time than conventional processes. In the method according to the present invention an item of footwear is assembled by placing an inner sole within an outer sole having an upturned peripheral edge receiving the inner sole, with peripheral portions of an upper portion fitting between the upturned peripheral edge of the outer sole and the inner sole. The outer sole, inner sole, and upper edge portion are each formed at least partially of a thermoplastic material at their adjoining surfaces and the inner sole, outer sole, and upper sole may then be sealed together by heating the adjoining surfaces. In this way, the three elements of the inner sole, outer sole, and upper portion can be secured together without the need for. the stitching, tacking or cementing typically performed by hand in conventional techniques for manufacturing items of footwear. Preferably, the inner sole is formed with downturned edges which are adapted to fit within the upturned peripheral edges of the outer sole, and the inner sole may advantageously be formed of a composite of a thermoplastic material with a outer covering of a fabric material. In this way, the exposed surfaces of the inner sole within the footwear item can be formed of such fabric materials as canvas or terrycloth to provide a high- quality surface for the foot of the users. Additionally, the thermoplastic portion of the inner sole may be a foamed thermoplastic shaped by thermoforming techniques. Additionally, the outer sole may also be formed by thermoforming techniques, and the upper portion of the footwear item may also be formed as a composite of a thermoplastic material with the outer layer of a fabric material to enhance the appearance of the footwear item. These and other objects, features and advantages of the present invention will be more readily apparent from the detailed descriptions of a preferred embodiment taken in conjunction with the following drawings, in which: Fig. 1 is a perspective view of a representative item of footwear manufactured according to the present invention; Fig. 2 is a cross section through II-II of Fig. 1. Fig. 1 illustrates a slipper or sandal that may be produced by the method of the present invention. It is, however, understood that the present invention can be applied equally to most any item of footwear, including recreational footwear such as sneakers and jogging shoes as well as boots, casual or dress shoes and the like. According to the present invention, an outer sole 1 is formed with its peripheral edge la turned upwardly to form a peripheral side wall. The outer sole includes a thermoplastic material on at least the inner surface of its side wall and preferably the entire outer sole is formed of a vinyl material such as PBC. The outer sole is shaped by thermoforming techniques to enable a large number of outer soles to be produced at a time. The inner sole 2 fits within the outer sole 1 and is formed with side walls adapted to lie along the side walls of the outer sole. The inner sole is formed with a thermoplastic material at least along the outer • surfaces of its side walls, and perferably the inner sole is formed from a foamed thermoplastic material such as a vinyl shaped by thermoforming techniques. If desired, the inner sole may be formed as a composite of a thermoplastic material such as PVC foamed with a high density and having a fabric material 2a such as canvas or terrycloth laminated over the outer surface of the thermoplastic backing in order to provide a more luxurious surface for the foot of the wearer. When a fabric material is laminated to the surface of the inner sole, a thermoplastic powder material may be embedded within those portions of the fabric material lying along the side wall portion of the inner sole, or the fabric material may be laminated only across the top surface of the inner sole without extending along the side wall portions. The upper portion 3 of the footwear item may be formed in any desired shape according to the item of footwear actually desired. As illustrated for representative purposes in the figures, the upper portion 3 is a band of material extending across the forward portion of the footwear so as to form an item such as a sandal or a slipper. The end portions of the upper portion 3 is fitted down between the side wall portions of the outer sole 1 and inner sole 2. As would be well understood in the art, the upper portion 3 may be in the form of a sneaker top or a top of a jogging shoe, casual shoe, boot or any other item of footwear. The peripheral portions of the upper portion 3 ' to be secured to the outer and inner soles are fitted down between the overlapping side walls of the inner and outer soles. At least those portions of the upper portions 3 fitting between the side walls of the inner and outer soles are formed of a thermoplastic material, and in one form of the present invention the upper portion is formed of a composite of a foamed thermoplastic material such as PVC overlaid with a fabric material such as terrycloth in the case of forming a slipper. If the terrycloth or other fabric is not sufficiently porous, a thermoplastic resin material may be embedded in edges of the fabric to be placed between the sidewalls of the inner and outer soles. Alternatively, of course, the upper portion could be formed of a foamed thermoplastic material suitably embossed or treated so as to simulate a fabric or leather material as is well understood in the art. With the peripheral edges of the upper portions sandwiched between the side walls of the inner and outer soles as illustrated schematically in Fig. 2, the entire peripheral edge of the item of footwear is subjected to a heating process to- seal adjoining surfaces of the side wall la of the outer sole, the depending side wall of the inner sole and the peripheral edge portion of the upper portion 3 therebetween to fuse them together into a unified assembly. In this way, the footwear item can be manufactured by placing the assembly of three pieces in position and then heat sealing them together without the need for extensive stitching, tacking or cementing, to provide a process that can be automated easily with a minimum of hand labor and production of steps. While the important features of the present invention has been illustrated above for the manufacture of a sandal or slipper type item of footwear, it would be well understood by those skilled in the art that the techniques described above could also be applied to the manufacture of almost any item of footwear. The present invention, therefore, is not limited to any particular type of footwear item, but to any item of footwear falling within scope of the present invention as defined in the appended claims.

Claims: What is claimed is: 1. A method of making items of footwear comprising the steps of assembling an inner sole within an outer sole having an upturned peripheral edge receiving said inner sole with peripheral portions of an upper portion fitting between said upturned peripheral edge and said inner sole, said outer sole, inner sole, and upper portion each being formed at least partially of a thermoplastic material at adjoining surfaces thereof, and sealing said inner sole, outer sole'and upper portion together by heating said adjoining surfaces. 2. A method according to claim 1, 'said inner sole having downturned edges*adapted to fit within the upturned peripheral edge of said outer sole. 3. A method according to claim 2, said thermoplastic material of said inner sole being foamed. 4. A method according to claim 2, said inner sole being formed as a composite of a thermoplastic material with an outer covering of a fabric material. 5. A method according to claim 1, said inner sole being formed as a composite of a thermoplastic material with an upper layer of fabric material. 6. A method according to claim 1, said inner sole being shaped by thermoforming techniques- 7. A method according to claim 2, said inner sole being shaped by thermoforming techniques. 8. A method according to claim 1, said outer sole being formed by thermoforming techniques. 9. A method according to claim 1, said upper portion being formed as a composite of a thermoplastic material with an outer layer of fabric. 10. An item of footwear comprising the steps of assembling an inner sole within an outer sole having an upturned peripheral edge receiving said inner sole with peripheral portions of an upper portion fitting between said upturned peripheral edge and said inner sole, said outer sole, inner sole, and upper portion each being formed at least partially-of a thermoplastic material at adjoining surfaces thereof, and sealing said inner sole, outer sole and upper portion being sealed together by heating said adjoining surfaces. 11. An item of footwear according to claim 10, said inner sole having downturned edges adapted to fit within the upturned peripheral edge of said outer sole. 12. An item of footwear according to claim 11, said thermoplastic material of said inner sole being foamed. 13. An item of footwear according to claim 11, said inner sole being formed as a composite of a thermoplastic material with an outer covering of a fabric material. 14. An item of footwear according to claim 10, said inner sole being formed as a composite of a thermoplastic material with an upper layer of fabric material. 15. An item of footwear according to claim 10, said inner sole being shaped by thermoforming techniques. 16. An item of footwear according to claim 11, said inner sole being shaped by thermoforming techniques. 17. An item of footwear according to claim 10, said outer sole being formed by thermoforming techniques. . . 18. An item of footwear according to claim 10, said upper portion being formed as a composite of a thermoplastic material with an outer layer of fabric.

Inventors: GREENBLATT DAVID H, GREENBLATT, DAVID, H.
Applicants: AMFESCO IND INC, GREENBLATT DAVID H, AMFESCO INDUSTRIES, INC., GREENBLATT, DAVID, H.
Application year: 1984
Main classification: A43B9
IPC codes: A43B3, B29D31