PROCESS AND APPARATUS FOR JOINING THE SOLE OF A SHOE TO ITS UPPER

摘要

1488214 Folding and seaming edges KOFLACH SPORTGERATE GmbH 27 Feb 1975 [27 Feb 1974] 8207/75 Heading B5K [Also in Division A3] The sole 12 of a shoe is joined to an upper 4, the sole and the upper consisting at least partially of thermoplastic synthetic resin, by positioning the upper 4 on a form 1 which has a face 6 of a shape corresponding to the shape of the sole 12 so that an edge 5 of the upper protrudes over the face 6 and so that the upper is stretched in the longitudinal direction of the form, bending the protruding edge 5 over the face 6, pressing the sole 12 against the face 6, and welding the sole 12 to the bent-over edge 5 by radio-frequency energy. As shown, the form 1 is divided along an oblique plane 2 into two parts 1a, 1b of which the part 1b is movable to a position 1b1 by a rod 3 operated by a pneumatic cylinder. The soleshaped face 6 may be planar or shaped to apply bent soles to the uppers of boots with heels. With the part 1b in position 1b1, the upper 4 is positioned around the form 1 with the edge 5 protruding above the face 6. The part 1b is lowered to increase the length of the face 6 so that the edge 5 is drawn inwardly at the toe and heel ends (51), Fig. 2 (not shown), of the upper to reduce the formation of undulations at these areas. Two jaws 7a, 7b, Figs. 4 and 6, of electrically insulating material, are moved inwardly by pneumatic cylinders 9 so that edges 10 thereon bend the edge 5 inwardly and surfaces 11 thereon press the upper 4 against the side surface of the form 1. The sole 12 is pressed downwardly against the edge 5 by a ram 13. The form 1 and the ram 13 are connected to the terminals of a high-frequency generator and form electrodes for the dielectric welding of the sole to the upper. The sole 12 may have a cover layer 14 and the ram 13 may be provided with an electrically insulating layer 15 for applying downward pressure to the centre of the sole 12 and for limiting the stroke of the ram 13. The sole 12 may consist at least partially of foamed synthetic plastics material having a greater thickness than the material of the upper 4. The upper and the sole may be made of thermoplastic synthetic material or may be made of leather or textile material provided with a layer of thermoplastic synthetic material. Specified thermoplastic synthetic materials are polyvinyl chloride, polyamide, polyurethane or polyolefin. In a modification, Fig. 8, the two jaws 7a, 7b of Fig. 4 are replaced by four jaws 7c, 7d, 7e, 7f.