Article Of Footwear And A Method For The Manufacture Of Said Article

Abstract

An article of footwear such as a sock, a pair of tights, combinations or any similar garment having at least one foot formed of knitted textile fabric and provided with a sole of flexible material having a fibrous structure, the sole being attached to the foot by means of a molded side portion of flexible plastic material which adheres to textiles and covers at least part of the periphery of the foot and of the sole.

Description

This invention relates to an article of footwear such as a sock, a pair of tights, combinations or any similar garment which has at least one foot of knitted textile fabric.

The invention is also concerned with a method for producing said article.

It has often been proposed to provide the lower portion of articles of the type referred-to above with a reinforcement for preventing premature wear of those regions of the foot which are the most exposed to friction. The reinforcement is usually obtained by means of pieces added by sewing, dipping or impregnation with plastic material or the like or alternatively by incorporating additional threads in the regions concerned.

However, these methods do not make it possible to obtain an article which has sufficient strength.

In another known design, the bottom portion of the foot of these articles has been provided with a molded sole of plastic material such as polyvinyl chloride.

A sole of this type enhances the strength and resistance of these articles to a considerable extent but the plastic material which forms said sole makes them uncomfortable to wear since it is conducive to perspiration of the foot. In addition, the plastic sole is liable to leave streaks on floors, paintwork and the like.

The aim of the present invention is to overcome the disadvantages mentioned in the foregoing by providing an article of footwear which is both strong and pleasant to wear and constitutes both a sock and a bedroom slipper which is particularly comfortable and is in no way liable to cause damage to furniture and paintwork even when the article is worn by children.

A further aim of the invention is to provide a simple and economical method for the manufacture of the articles aforesaid.

In accordance with the invention, the article of footwear such as a sock, a pair of tights, combinations or any garment having at least one foot of knitted textile material, said foot being provided with a sole, the article being characterized in that said sole is of flexible material having a fibrous structure and that said sole is attached to said foot by means of a molded side portion of flexible plastic material which adheres to textiles and covers at least part of the periphery of the foot and of the sole.

Said article of footwear therefore constitutes an article of footwear at the same time since the sole is secured to the foot of the article by means of the side portion of plastic material.

The fact that the sole is of flexible fibrous material makes the article particularly comfortable at the time of use.

Moreover, the side portion of plastic material which ensures attachment of the sole to the foot of textile material provides a perfect support for the wearer's foot and at the same time protects this latter against the many shocks to which it is exposed.

In a preferred embodiment of the invention, the sole is so arranged as to project from the bottom portion of the foot.

In this manner, the plastic material which constitutes the side portion also covers the top edge of the sole, thereby increasing the area of sole which is covered by the plastic material and further strengthening the attachment of the side portion to the sole.

In another preferred embodiment of the invention, the material forming the sole is selected from the velvet-pile fabrics, the tagged carpeting and felt fabrics and the material forming the side portion is selected from polyvinyl chloride, polyurethane resin and rubber.

When in use, the article in accordance with the invention provides a remarkable degree of comfort as a result of the materials which are chosen for the sole as mentioned in the foregoing. These materials are in fact known for their softness and flexibility as well as for the pleasant feel which they afford as floor covering materials.

Soles formed of materials of this type offer a further advantage in that they do not produce streaks or scratches on floors, paintwork, furniture or any other household object. Such materials are also resistant to wear.

The plastic materials employed for the side portion have the advantages of being inexpensive and highly resistant as well as being flexible. Moreover, when simply molded in the hot state, said materials are strongly adherent to synthetic and natural textiles of the types which are in common use.

In one advantageous embodiment of the invention, the article of clothing further comprises an intercalary sole placed between the foot of knitted textile material and the sole of flexible material which has a fibrous structure.

It has been found that the comfort provided by the article is even further enhanced by the presence of said intercalary sole between the foot of knitted textile material and the sole of flexible material having a fibrous structure.

Said intercalary sole additionally makes the article even stronger in use by virtue of the fact that its presence limits any frictional contact between the foot of knitted textile material and the sole. Said intercalary sole makes it possible in addition to improve the insulation of the foot which is provided by the sole of fibrous material.

The periphery of said intercalary sole is preferably attached to the side portion of plastic material which covers the periphery of the foot and of the sole of flexible material of fibrous structure.

Since the periphery of the intercalary sole is securely attached to the side portion of plastic material, any sliding of the intercalary sole relatively to the sole of fibrous material is thus prevented.

In accordance with the invention, the method for the manufacture of the article of clothing aforementioned is characterized in that the foot of the article is fitted over a rigid forming-block, the sole is placed at the bottom of a mold, the end of the forming-block which carries the foot is engaged in the mold, the bottom portion of the foot is maintained applied against the sole and a substance which adheres to textiles such as polyvinyl chloride, polyurethane resin and rubber is injected into the mold in order to form the side portion.

The injected plastic material thus fills the unoccupied lateral space between the mold and the forming-block which carries the foot.

In the case of socks, the method is advantageously employed in a machine for the manufacture of shoes by injection molding

Further properties and advantages of the invention will become apparent from the following description, reference being made to the accompanying drawings which are given by way of non-limitative example, and in which:

--FIG. 1 illustrates a sock which constitutes an article of footwear in accordance with a first embodiment of the invention;

--FIG. 2 is a transverse sectional view taken along line II--II of FIG. 1;

--FIG. 3 is a sectional view of a sock which constitutes an article of footwear in accordance with a preferred embodiment of the invention;

--FIG. 4 is a view to a larger scale showing the front portion of FIG. 3;

--FIG. 5 is a view in sectional elevation showing the forming-block carrying the foot of a sock which is engaged in the mold as contemplated by the method according to the invention;

--FIG. 6 is a sectional view taken along line VI--VI of FIG. 5;

--FIG. 7 is a longitudinal sectional view of an article of footwear comprising an intercalary sole;

--FIG. 8 is a transverse sectional view taken along line VIII--VIII of FIG. 7;

--FIG. 9 is a longitudinal sectional view of an article of footwear comprising an alternative design of intercalary sole;

-- FIG. 10 is a longitudinal sectional view of an article of footwear comprising a further alternative design of intercalary sole;

-- FIG. 11 is a transverse sectional view taken along line XI--XI of FIG. 10;

-- FIG. 12 is a partial longitudinal sectional view of another alternative design.

In the embodiment which is illustrated in FIGS. 1 and 2, the article of footwear in accordance with the invention comprises a conventional sock 1 of knitted textile material which may be either natural, artificial or synthetic, the foot 2 of said sock being provided with a sole 3 of velvet-pile fabric. That face of said fabric which is in contact with the bottom portion of the foot comprises a layer 4 of plastic material in which the fibers of synthetic or natural textile material are embedded. The sole 3 is attached to the foot 2 by means of a molded side portion 5 of polyvinyl chloride which covers the periphery of the foot 2 of the sock over a small part of its height as well as the top edge of the sole 3.

As indicated in FIG. 2, the sole 3 is preferably arranged so as to project with respect to the bottom portion of the foot in order to increase the area of the sole 3 which is covered with polyvinyl chloride and thus to strengthen the attachment of the foot 2 of the sock to the sole 3.

A material of fibrous structure other than velvet-pile fabric can be employed for the sole 3 and can consist, for example, of felt and tagged carpeting which are also both flexible, soft and wear-resistant.

The side portion 5 can also be of plastic material other than polyvinyl chloride and can consist, for example, of polyurethane foam and rubber which also have excellent properties of adhesion with respect to textiles and make it possible to ensure excellent attachment of the sole 3 to the sock 1.

The sock 1 which is thus provided with the sole 3 constitutes at the same time an article of footwear which can be employed in particular as a bedroom slipper, especially by reason of the high degree of comfort afforded by the sole of velvet-pile fabric, felt or tagged carpeting material.

In one of the preferred embodiments which is illustrated in FIGS. 3 and 4, the side portion 5 is provided with extensions in the form of reinforcement coverings 6a, 6b over part of the end portion of the foot and of the heel. The coverings 6a, 6b serve to reinforce the ends of the foot and of the heel which are the most exposed to shocks.

The thickness of each covering 6a, 6b is preferably smaller than that of the side portion 5 in order to ensure that a high degree of suppleness is retained in the corresponding portions of the sock.

By way of example, the thickness of the side portion 5 can be of the order of a few millimeters whereas the thickness of the reinforcement coverings 6a, 6b is preferably smaller than or equal to approximately one millimeter.

It is also an advantage to ensure that the portion 7 of the foot 2 of the sock which is covered by the side portion 5 of plastic material is knitted in close stitches as shown in FIG. 4. This prevents the penetration of the plastic material into the sock at the time of molding of the side portion 5. This portion 7 in closely-knitted stitches can be obtained at the time of knitting of the sock by incorporation of additional threads in the portion concerned.

In order to form socks of this type which are provided with a sole, it is an advantage to make use of an automatic machine for the manufacture of shoes by injecton molding, for example of the type constructed by Etablissements Lucas at Bordeaux under reference C 400.

A machine of this type comprises a number of molding stations, an injection device which is supplied with polyvinyl chloride or like plastic material being moved in front of said stations.

Each station comprises in particular a mold 10 formed in two sections and having an injection passage 11 which opens into the mold cavity 12 as shown in FIGS. 5 and 6.

In the method according to the invention, the foot 2 of the sock 1 is fitted over the rigid forming-block 13 which has the general shape of a foot, the sole 3 is placed at the bottom of the cavity 12 of the mold 10, the end of the forming-block 13 which carries the foot 2 is engaged within the mold 10, the bottom portion of the foot is maintained applied against the sole 3 and the plastic material in the form of paste in the hot state is injected into the mold 10 through the injection passage 11.

The plastic material thus fills the space 14 which is delimited by the walls of the cavity 12, the portion of the foot 2 which is engaged in the mold 10 and the top edge of the sole 3.

The space 14 corresponds exactly to the external shape of the side portion 5 and can also have extensions (not shown in the drawings) for molding the reinforcement covering 6 over the end of the foot and of the heel as shown in FIGS. 3 and 4.

The bottom 15 of the cavity 12 must be adapted to the shape of the sole 3 in order to ensure that there is a permanent contact between the periphery of the sole 3 and the mold in order to prevent the injected plastic material from passing between these latter.

For the same reason, the top edge 16 of the cavity 12 must have a contour which is perfectly adapted to the shape of the foot 2 in order to ensure permanent contact between the foot 2 and the mold.

Moreover, the plastic material is prevented from passing between the bottom portion of the foot 2 and the sole 2 by maintaining the forming-block 13 applied against the sole during the injection process.

When the time required for cooling the injected plastic material has elapsed, the mold 10 is opened by separating its two sections. When the sock 1 has thus been joined to the sole 3, a bead of plastic material corresponding to the passage 11 remains attached to the side portion 5 and only requires to be broken off at the level of this latter.

There is thus obtained an article of footwear of the type described with reference to FIGS. 1 to 4 and comprising a sole 3 which is securely attached to the foot 2 of the sock by means of the side portion 5.

The articles of footwear which are thus obtained have excellent resistance to wear; they provide a highly satisfactory degree of comfort, especially by virtue of the sole of velvet-pile fabric, felt or tagged carpet material and the cost of manufacture of such articles is remarkably moderate.

In yet another embodiment which is even more advantageous than the previous designs and is illustrated in FIGS. 7 and 8, the article of footwear further comprises an intercalary sole 24 between the foot 21 and the sole 22 of fibrous material. In the embodiment of FIGS. 7 and 8, said intercalary sole 24 is of constant thickness, has a perimeter which corresponds substantially to that of the sole 24 and is attached along its periphery to the side portion 23.

Accordingly, the foot 21, the intercalary sole 24 and the sole 22 are secured to each other by means of the side portion 23, no means of attachment such as gluing being provided between the different contacting surfaces.

By way of example, the intercalary sole 24 can be formed by comfortable insulating material such as cork or wool.

In the embodiment of FIGS. 9 to 11, the intercalary sole is of greater thickness in the vicinity of the heel of the foot 21.

In FIG. 9, the intercalary sole 25 is provided with a flat surface on the side facing the sole 22 of velvet-pile fabric and has a thickness which varies progressively in the portion 25a which is located between the end of the foot and the heel. The consequence of this arrangement is that the comfort of the article of footwear is enhanced since the pressure exerted by the foot is more evenly distributed over the sole 22 of velvet-pile fabric.

In FIG. 10, the surface of the intercalary sole 26 is flat on the side facing the foot 21 and has a heel 26a on the other side. The side walls of said heel 26a are entirely covered by the molded side portion 23a of polyvinyl chloride, only the bottom portion of the heel 26a being in contact with the sole 22b of velvet-pile fabric. The heel 26a is thus wholly protected against lateral shocks.

In FIG. 12, the periphery of the intercalary sole 27 is not attached to the side portion 23 of plastic material. The perimeter of the sole 27 is slightly smaller than that of the sole 22 of velvet-pile fabric in order that the periphery of the foot 21 may thus be permitted to come directly into contact with the top edge of the sole 22. The foot 21 is thus attached directly to the sole 22 by means of the side portion 23.

The fabrication of articles of footwear fitted with a sole of fibrous material and with an intercalary sole such as the sole 24 shown in FIG. 7 can be carried out by adopting a method which is similar to that described with reference to FIGS. 5 and 6.

To this end, the foot 21 of knitted textile material is fitted over the rigid forming-block 13, the sole 22 of fibrous material is placed at the bottom of the mold 10, the intercalary sole 24 is placed on said sole 22, the end of the forming-block 13 which carries the foot 21 is engaged in the mold 10, the bottom portion of the foot 21 is maintained applied against the intercalary sole 24 and a plastic material such as polyvinyl chloride is injected into the mold 10 so as to mold the side portion 23.

The pressure developed in order to apply the foot 21 against the intercalary sole 24 which is placed on the sole 22 must be of sufficient value to ensure that there is a permanent contact between the knitted textile material of the foot 21, the intercalary sole 24 and the sole 22 of fibrous material with a view to preventing the injected plastic material from passing between these different parts.

It is readily apparent that the invention is not limited to the examples of construction which have been described in the foregoing.

In particular, the invention also applies to articles such as tights, combinations or any other garment which has at least one foot. Moreover, the colors employed both for the molded plastic material which forms the side portion and for the material which forms the sole can be selected as a function of the colors of the socks or other garments of the type in which a foot is provided.

The shape of the intercalary sole can also be modified with a view to adapting this latter to certain orthopaedic applications.

It will also be noted that cleaning of the articles described in the foregoing can be carried out by ordinary household washing and even in a washing-machine if the textiles are judiciously chosen.

Claims

What I claim is:

1. Article of footwear comprising a sock of knitted textile material, a sole of flexible material having a fibrous structure selected among the group consisting of velvet-pile fabrics, felt fabrics and tagged carpet fabrics, a molded side portion of plastic material selected among the group consisting of polyvinyl chloride, polyurethane resin and rubber which covers at least part of the periphery of the foot of the sock and the periphery of the sole and attaches the sole to the sock, said part of the periphery of the sock which is covered by the plastic material being knitted in sufficiently close stitches to prevent the penetration of the plastic material through the stitches.

2. A method for the manufacture of an article of footwear comprising:

a. fitting a sock of knitted textile material over a rigid forming-block having the general shape of a foot, at least part of the periphery of the foot of the sock being knitted in close stitches;

b. placing on the bottom of a mold a sole of flexible material having a fibrous structure selected among the group consisting of velvet-pile fabrics, felt fabrics and tagged carpet fabrics;

c. engaging in said mold the end of the forming-block which carries the foot of the sock;

d. maintaining the bottom portion of the foot of the sock applied against the sole;

e. injecting into the mold a hardenable plastic material selected among the group consisting of a polyvinyl chloride, polyurethane resin and rubber, in order to form on said part of the periphery of the foot of the sock which is knitted in close stitches and on the periphery of said sole of flexible material a molded side portion;

f. and after the plastic material has hardened removing the article of footwear from the mold.

3. A method as claimed in claim 2, and maintaining said sole applied against the bottom of the mold until said plastic material is hardened thereby to prevent the plastic material from passing between the sole and the mold.