GB2063054A - Non-slip material, in particular for shoe soles - Google Patents

Abstract

A material having non-slip characteristics is formed by moulding an elastomeric material around at least one layer of metal fabric knitted from at least one strand of metal, such as steel wool. Such material is particularly suitable for shoe soles, which soles may contain a plurality of layers of knitted metal fabric (9), and optionally have studs (4, 5, 6, 7, 8) containing rolls of knitted metal fabric (10). <IMAGE>

Description

SPECIFICATION Non-slip material, in particular for shoe soles The present invention relates to a non-slip material in particular for shoe soles of elastomeric material, and to soles and shoes made therefrom.

Various non-slip sole structures have been suggested in a number of patents, the non-slip quality of the said soles being obtained by incorporating a variety of inserts during moulding. Thus, a French Patent No. 725,274 (Duchemin) discloses that it is possible to combine metal sheets, fibres, strands or plates with the rubber of a sole in order to form anchoring points which prevent slipping. As a further example, French Patent No.691,569 (Dan Den Abelle) discloses that the metal component can be formed of bearded needles which are directed perpendicularly to the plane of the sole and are incorporated therein during moulding. According to Swiss Patent 170,065 (Trafelet) the insert can be a steel netting; according to U.S. Patent 2,557,946 (Crooker) the insert is a raised metal wire on the sole.

Other patents disclose that the insert can be a filling of metal shavings confined in the sole at the time of moulding.

It has now surprisingly been discovered that another type of insert to those previously proposed has great advantages in that it has proved particularly effective as a means of preventing slipping, that it can be obtained at an economic price due to the fact that it is already being produced industrially on a relatively large scale for a different purpose and that it avoids certain problems that exist when prior art inserts are to be moulded in.

According to one aspect of the present invention there is provided material having non-slip characteristics formed by moulding an elastomeric material around at least one layer of metal fabric knitted from at least one strand of metal.

According to a second aspect of the present invention there is provided a sole comprising a portion having non-slip characteristics formed by moulding an elastomeric material around at least one layer of a metal fabric knitted from at least one strand of metal.

Such a knitted metal fabric made from steel, is well known to housewives under the name of "steel wool" and is intended for scrubbing wooden floors.

This knitted structure of the insert of the invention, certain characteristics of which will be seen further on, is distinguished clearly from the inserts proposed in the prior art; it is distinguished, for example, from the netting, in which the metal strands or wires extend only in two directions, at right angles to one another; it is also distinguished from the shavings, which undoubtedly could extend in all directions, but which have the disadvantage of being displaced during injection of the flexible material into the mould. The knitted insert of the invention is more closely comparable to this latter type of insert in terms of non-slip performance, but it has the advantage over thins type of insert in that it better retains its 3-dimensional structure and position when in the mould and so is not displaced during injection of the elastomer.Such displacement is liable to lead to poorer non-slip performance, or else requires expensive precautions to avoid it.

Preferably, the metal strand forming the said knitted structure has a rectangular section; it will be noted that, owing to the "knitted" structure and contrary to what would happen in the case of a woven structure ofthe mesh type, each strand has, by and large, the larger dimension of its cross-section per pendicularto the plane of the knitted structure and hence to the plane of the sole, the result of which is to increase considerably the non-slip effect; it will be noted that this arrangement is the reason for the abrasive qualities which are well known in the aforementioned customary application of steel wool.

Still with a view to improving the non-slip qualities of a sole embodying the invention, a knitted structure comprising two or more juxtaposed strands is preferably chosen; this juxtaposition of strands is instrumental in keeping each of them on edge relativeto the plane of the knitted structure.

Metal knitted structures of this type are generally and advantageously obtained by circumferential or circular knitting; the Applicant has observed that by cutting short sections out of the cylinders of knitted structure thus obtained, and by pulling the cut-out sections transversely, a ring or elongated coil of mesh is formed; in this coil of mesh, the strands of rectangular section have their larger sectional dimension perpendicular to the annular surface. The Applicant has made use of this observed result to impart the non-slip quality to soles which are provided with wide projecting studs on their lower surfaces; thus in accordance with a preferred embodiment of the invention, these projecting studs incorporate a roll of the metal knitted structure, the roll being moulded in at the same time as the elastomer forming the sole is moulded.The rolls are produced by cutting of the aforementioned knitted cylinders into sections.

In accordance with another embodiment of the invention, relating to a flat sole or a sole without studs, the knitted metal fabric is exposed at least in the central part of the sole. This result is obtained when, by arranging in the mould the number of layers of knitted structure which are necessary for filling the mould completely, a piece of cloth with a surface area smaller than that of the sole is placed against the wall of the mould corresponding to the lower surface of the sole. When the mould is closed, the knitted metal fabric is embedded in the said piece of cloth, which cloth thus forms a space from which elastomer is excluded on injection; when the mould is opened, it will be sufficient to detach the piece of cloth in order to reveal below it the exposed section of the knitted metal fabric.

The present invention can be used to provide soles for all kinds of footwear such as boots, safety shoes, sports shoes, moulded overshoes and all other types where the sole forms an integral part of a moulded shoe. The present invention can also be used in the production of a sole which is to be fixed temporarily to the bottom of a shoe with the aid of appropriate fixing means; it can also be used in the production of sheets of semi-finished materials for making or repairing shoes. Also, material according to the invention can be used in the production of remoulded or original treads for pneumatic tyres for vehicles, and other uses are possible too.

Particular embodiments of the present invention will now be described by way of example, with reference to the accompanying drawings, in which: Fig. 1 shows a view to scale of a knitted fabric of metal strands (or steel wool) which is particularly well suited for application in embodiments of the invention; Fig. 2 shows an enlarged detail of the knitted fabric of 1; Fig. 3 is a view, in cut-away perspective, of the metal strands of the steel wool of the previous figures; Fig. 4 is a view from below of a boot sole; Fig. 5 is a section along a line A-A of the sole of Fig.

4; Fig. 6 is a view from below of a sole which comprises an exposed metal insert according to the invention; and Fig. 7 shows a non-slip sole which can be detachably fitted to the bottom of a shoe.

In Figs. 1,2 and 3, a metal insert, which is intended for moulding at the same time as an elastomer to form a non-slip sole is composed of a knitted fabric of two juxtaposed metal strands or wires 2 and 3; what is meant by a knitted structure is a twodimensional juxtaposition of loops which are interwoven in one another; a texture of this type is produced, in contrastto weaving, by means of a single thread (which can be composed of one or more strands). The fabric shown in Figs. 1 and 2 is one of the simplest and is obtained by circular knitting.

However, it should be understood that other types of knitting may be used, which may be more complex, such as "crochet" loop or other loop. One important feature of such knitted fabrics lies in the fact that any flattened strand used is set on its edge as a consequence of the knitting.

In Figs. 4 and 5 there is shown a shoe sole comprising, on its lower face, raised chevrons 4, 5, 6 which form studs. The same applies to the heel which has the chevrons 7 and 8. When a sole of this type is moulded from an elastomeric material, pieces of knitted metal fabric, which have been previously cut to correspond to the shape of the sole, are arranged in a plurality of layers in the mould. These layers appear in the area 9 of the section in Fig. 5. Thin rolls of knitted metal fabric 10, which are obtained, as stated above, from a cut cylindrical knitted metal fabric, are also arranged in those hollow parts of the mould which are intended for forming the chevronshaped studs.

Fig. 6 shows a shoe sole which has simply been moulded from an elastomeric material to provide lower surface without projections; like the sole in the Fig. 5, this sole has incorporated in it during moulding knitted metal fabric layers which are placed in the central part of the front of the sole. In accordance with a preferred embodiment of the invention the sole is moulded with a cloth in the bottom ofthe mould engaging the lowest layer of knitted metal fabric. After moulding the cloth can be stripped off which will expose the lowest knitted metal layer as can be seen at 11 in the central part of the sole. The resulting advantage is that the sole has a non-slip quality immediately without the necessity for preliminary wearing ofthe elastomer. Alternatively it is possible to rub down the sole until the metal mesh appears and, therefore, to dispense with the cloth.

In Fig. 7 a sole 12, which incorporates a plurality of knitted metal layers and which can be advantageously shaped on its inner face to correspond to the style of the sole in Fig. 6, is intended for fixing temporarily to the bottom of a shoe with the aid of a front strap 13 and a heel strap 14 and instep strap 15.

Claims (11)

1. Sole comprising a portion having non-slip characteristics formed by moulding an elastomeric material around at least one layer of a metal fabric knitted from at least one strand of metal.

2. Sole according to claim 1 wherein the metal strand has a rectangular cross-section.

3. Sole according to claim 1 or 2, wherein the meal fabric is knitted from two juxtaposed metal strands.

4. Sole according to any one of the preceding claims, wherein said portion comprises several studs on the bottom of the sole.

5. Sole according to claim 4, wherein said studs incorporate a roll of said metal fabric.

6. Sole according to any one of claims 1 to 4, wherein the portion extends over the central portion of the front of the sole.

7. A sole according to any preceding claim further comprising means for fixing it to a shoetem- porarily.

8. A sole substantially as hereinbefore described with reference to the embodiment of Figs. 1, 2 and 3, or Figs. 4 and 5, or Fig. 6.

9. A shoe comprising a sole as claimed in any of claims 1 to 6 or 9 integral therewith.

10. A sole substantially as hereinbefore described with reference to the embodiment of Fig.

7.

11. Material having non-slip characteristics formed by moulding an elastomeric material around at least one layer of metal fabric knitted from at least one strand of metal.