CS216499B1 - the method of knocking the edges of the shoe upper parts - Google Patents

Abstract

The invention relates to a method of tapping the edges of upper parts of footwear by thermal activation of a reinforcing and connecting component fed into the folded edge of the part during its gradual movement by a tapping device. The essence of the invention lies in the fact that a textile edging is fed into the folded edge of the part, which consists of reinforcing yarns and thermoplastic yarns, the fibers of which are plasticized to a sticky state at the temperature of the thermal activation environment. The invention can be used in the production of footwear and haberdashery products.

Description

BACKGROUND OF THE INVENTION The present invention relates to a method of knocking the edges of an upper part of a shoe by thermally activating the reinforcing and connecting component fed to the folded edge of the part as it is progressively coated by the knocking device.

By tapping, the edge of the upper part of the shoe is both visually modified and reinforced. The requirements for reinforcing the knocked edge of a part are different. In the case of those edges of the parts which, after being knocked, are joined by β with another part, eg by stitching, sufficient reinforcement is usually achieved by the actual folding of the material of the vice. Greater demands are placed on reinforcing the knocked edge of the part, which then forms the top edge of the finished shoe upper. The problem of reinforcing the upper edge of the upper of the shoe arises especially in the case of women's boat shoes, where it is necessary that the edge itself, without the help of laces, buckles or other means, sufficiently and at the same time flexibly and comfortably abut the entire circumference.

There is known a method of knocking the edges of the upper parts of a shoe, in which the bevelled edge of the part is pre-coated with glue and subsequent folding and knocking as it passes through the knocking device and the folded edge is completely glued. This method is laborious and costly because it requires a preliminary adhesive coating. At the same time, especially in the case of softer upper materials, sufficient knocking edge reinforcement was not achieved in this way. Therefore, in these cases, it was necessary to insert a reinforcing bead into the folded edge, which also had to be pre-coated with an adhesive. This caused a further increase in labor and production costs.

There is further known a method of knocking the edges of the upper parts of the shoe, in which the thermally activates the surface of the thermoplastic layer of the upper part, the lining part or the reinforcing trim to the adhesive state. This method is very productive since it does not require laborious glue application. However, the vast majority of materials used to produce shoe uppers do not have a surface layer that can be thermally activated to a sufficiently tacky state. The required thermoplasticity of the surface of the upper materials tends to be in contradiction with the required rigidity of the material. Therefore, the edges of the upper parts knocked in this manner were usually not sufficiently reinforced.

Is the method of knocking the edges of the upper parts of the shoe by thermal activation also known? a thermoplastic resin applied to the reinforcing yarn, which is fed to the folded edge of the part as it is progressively moved through the knocking device. In this method, it is also necessary to laboriously pre-coat the thermoplastic resin on the reinforcing yarn.

Such deposition of thermoplastic resin is generally formed in the form of a circular cross-section. In order to get enough thermoplastic resin into the folded edge of the workpiece, this circular cross-section had to be quite large, which, however, caused difficulties in thermal activation. In fact, it has been difficult to sufficiently plasticize the circular circular cross-section so as to be able to evenly distribute evenly over the width of the folded part when it is knocked in a relatively rapid passage through the thermal activation environment. Moreover, even in this method, it was difficult to produce the necessary combination of reinforcing yarn and quantity

216,499 of thermoplastic resin applied thereto. In softer Upper Materials, the reinforcing yarn usually did not provide sufficient reinforcement to the knocked edge of the part.

These disadvantages are eliminated by the method of knocking the edges of the shoe upper parts,

The principle of this invention is to provide a textile bead, which consists of reinforcing yarns and thermoplastic yarns, the fibers of which are plasticized to a sticky state at the temperature of the thermal activation environment.

A higher effect of the method according to the invention is that by selecting the type and ratio of the number of reinforcing yarns and the thermoplastic yarns and their mutual bonding, the reinforcing and adhesive properties of the edging can be very advantageously adjusted according to the needs of the topsheet materials used. The individual fibers of the thermoplastic yarns are relatively thin, which advantageously creates a large surface. By passing through the thermal activation environment, these thermoplastic fibers easily plasticize. In this way, the individual reinforcing yarns are glued together and as a whole a component is formed which, if necessary, reinforces and sufficiently connects the folded and knocked edge of the upper part.

In the verification tests, the textile knitting bead was used, whose reinforcing yarns were cotton, while the thermoplastic yarns were of polyamide or polyester fibers. The choice of thermoplastic yarn type was governed by the type of knocked uppers. For example, polyamide fibers have a chemically related composition to the collagen fibers that make up natural leather. Therefore, when knocking off the edges of natural leather parts, the best strength of the glued joint with the textile hem, whose thermoplastic yarns were polyamide. Conversely, when knocking parts of some synthetic leather containing polyester components, it was preferable to use a textile trim with thermoplastic polyester fiber yarns.

Example of method implementation.

The edge of the upper part of the shoe, cut from natural leather, is bevelled and then guided through the knocking device, where it gradually folds inwards with the reverse side. At the same time, the folded edge of the workpiece is fed with a textile seam consisting of cotton reinforcing yarns and polyamide yarns. Immediately at the entrance to the folded edge of the fabric portion, the textile seam passes through a thermal activation environment, which is generated by a stream of hot air exiting the heated nozzle. The fibers of the polyamide yarns are activated into the sticky state by hot air, thereby bonding the individual cotton yarns together. As a whole, the textile seam creates a component which forms a glued joint in the folded edge of the part as it is gradually moved by the knocking device.

The knocked edge of the part sufficiently reinforces the cotton fibers.

Of course, other than knitted weaves, such as woven fabrics, can be used for the production of textile trimmings. The reinforcing yarns may be of various vegetable, animal or synthetic fibers which do not plaetify at the temperature of the thermal activation environment.

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Fibers of other copolymers, or mixtures thereof, can be used for thermoplastic yarns that sufficiently provide a tacky state at the temperature of the thermal activation environment.

The method of knocking the edges of the upper parts according to the invention can be used in particular in the manufacture of shoe clamps, but also in the haberdashery production.

Claims (1)

SUBJECT OF THE INVENTION A method of knocking the edges of an upper part of a shoe by thermally activating the reinforcing and fastening component supplied to the folded edge of the part as it is progressively moved through the knocking device, characterized in that at ambient temperature, thermal activation plasticizes to a sticky state.