Patent ID: 12207698

DETAILED DESCRIPTION

FIG.1shows a first example of a knitted tubular component10made as a single piece15, including a first knitted tubular part20and a second knitted tubular part30, each one of which is elbow-bent. The knitted tubular component10thus has a substantial U-shape. The first and second knitted tubular parts20,30are of unitary knitted construction with the knitted tubular component10. The first knitted tubular part20may include an open distal end22, which may be closed by sewing before disposition on the preform50, an open proximal end24delimiting an area of insertion of the foot26, as well as a volume28for housing the foot. The second knitted tubular part30may include a distal end32closed during the knitting of the tubular component10, and an open proximal end34delimiting an area of insertion of the foot36as well as a volume38for housing the foot. In an example, the first and second knitted tubular parts20,30may include respective heel areas25,35intended to receive the heel of the foot of the user. During the programming of the knitting machine to knit the knitted tubular component10, the zoning of the first and second knitted tubular parts20,20is determined according to different knit schemes (reverse jersey, straight jersey, ribbing etc.) and different types of yarn (differing by their nature and/or their color and/or their transparency and/or their titer (dtex)). It is thus possible to vary the relief, thickness, appearance, and functionality of the determined area or areas, and this for the first knitted tubular part20and the second knitted tubular part30, independently of one another.

Alternatively, a single one of the first and second tubular parts20and30may include an elbow-bent portion such that the tubular component10has a general L-shape.

The first knitted tubular part20may include at least partly fusible yarns disposed in one or more portions. The second knitted tubular part30may also include one or more fusible portions formed of at least partly fusible yarns. The at least partly fusible yarns for example account for at least 30% in weight, and at the most 60% in weight, of the total weight of the first knitted tubular part, and are distributed over the entirety of the latter. Alternatively, the first knitted envelope20may be essentially composed of fusible yarns.

The at least partly fusible yarns account, for example, for at least 50% in weight, and at the most 80% in weight, of the total weight of the second knitted tubular part, and are distributed over the entirety of the latter. This disposition can of course vary according to the stability and flexibility desired.

FIG.2shows the first knitted tubular part20in bottom view, the sole part27of which may include a longitudinal flattening opening29disposed between the front27aand back27bedges. The longitudinal opening29is a through opening, i.e. it opens both on the outer face21and the inner face23of the first knitted tubular part20. The opening29is formed of a single substantially straight segment. The longitudinal opening29is delimited by a medial edge29aand a lateral edge29b, and has a length l1between 50% and 90% of the length p of the sole part27, including between 60% and 80% of the length p.

FIG.3shows a second example of a knitted tubular component100also made as a single piece150, including first and second knitted tubular parts200and300. The knitted tubular component100is substantially straight, the first and second tubular portions200and300not including any elbow portions. The sole part270may include a longitudinal opening290similar to the longitudinal opening29.

The longitudinal opening29of the knitted tubular component10makes it possible to flatten the first tubular part20on a support S as shown inFIG.4in top view for its functionalizing, here of the outer face21of the forefoot, medial and lateral parts of the first knitted tubular part20.FIG.4thus shows an upper planar portion42of the first knitted tubular part20, opposite a planar lower portion44shown inFIG.5. The open distal end22can be closed before or after the functionalizing step (iii) to form the tip of the foot receiving the toes of the first knitted tubular part20. Advantageously, the flattening longitudinal opening29is formed during the knitting of the first knitted tubular part20, and therefore of the knitting of the knitted tubular component10. The medial and lateral edges29aand29bmay not include any cut threads. They can for example be formed by stitch transfer, such that they do not risk unraveling. This is because the unraveling of the edges could alter the structure of the sole part27and propagate to the other parts of the first knitted tubular part20. The longitudinal opening29formed by knitting makes it possible to dispense with a cutting-out step, to form an opening, the position and size of which are reproducible but also to improve the stability of the structure during the functionalizing when flat.

Four functional components75are secured to the outer face21, for example by a seam, or a weld (particularly heat welding, for example ultrasonic) or using an adhesive agent. The functional components75are cited by way of non-limiting example for illustrative purposes; other functional components could be implemented, and according to different regions on the outer face21and/or the inner face23of the first knitted tubular part20. The size and location retained for the functional components are however limited to the available planar surface shown inFIG.4. The second knitted tubular part30is not shown for simplicity's sake inFIGS.4and5. Here the outer face21is available to be functionalized but the first knitted tubular part20could be turned over and flattened to functionalize its inner face23. As can be seen inFIG.7, the footwear assembly40also may include a functional component60which is a heel reinforcement and a functional component70which is a shock-absorbing instep. The functional components60and70are disposed between the first and second knitted tubular parts20and30, respectively between the instep parts and the hindfoot parts at the level of the heel. The functional component60extends vertically to the longitudinal axis L. These components70and60are not shown inFIGS.4and5for simplicity's sake, but may be secured to the inner face23of the upper planar portion42of the first knitted tubular part20.

The longitudinal opening29is then closed, particularly using a seam35in order to restore volume to the footwear assembly40, then the footwear assembly40is placed on a preform50as shown inFIG.7to undergo a transforming step (iv) during which the preform50covered in the footwear assembly40is placed in a molding volume80. The molding volume80is delimited between, on the one hand, the preform50covered in the footwear assembly40and on the other hand, the volume formed by a mold90made of two parts95and96. The inner volume of the mold90substantially corresponding to the footprint of the foot-shaped preform50. Alternatively, the molding volume can also be delimited between the outer surface of the preform50and a flexible airtight membrane, comprising a hollow form substantially in the foot shape to fit the footwear assembly disposed on the preform50.

Heat, particularly combined with water vapor, is then applied to the footwear assembly40in order to thermoform the footwear assembly40to the foot shape of the preform50. The fusible portion(s) may include the first knitted tubular part20and eventually include the second knitted tubular part30, is/are melted/softened during the transforming step (iv). The footwear assembly40is also compressed against the outer surface of the preform50. The footwear assembly40, still on the preform50, is then cooled, particularly at ambient temperature, and then keeps the shape of the outer surface of the preform50. This transforming step (iv) further allows the thermoforming to secure to one another the first and second knitted tubular parts20and30particularly at least partially according to their respective inner23and outer31faces.

The knitted tubular component10may alternatively include solely the first knitted tubular part20. In this case, the transforming step allows only the thermoforming of the first knitted tubular part without securing.

Alternatively again, the first knitted tubular part20can be disposed in the inner volume38of the second knitted tubular part30. The second knitted tubular part then forms the outer layer of the footwear assembly and the first knitted tubular part forms the inner layer.

The preform may also include perforations, in particular having a diameter of 5 mm to 10 mm approximately, opening onto an inner volume of the preform such that the perforations and the inner volume of the preform are in fluid connection. The perforations make it possible to inject water vapor over the footwear assembly starting from the inner volume. This disposition makes the obtained upper more flexible.

The transforming step (iv) allows the formation of an upper400, the sole part450of which is then secured to a sole element500for the obtaining of the footwear article1shown inFIG.9. The upper400may thus include different knitted areas401to406for the first knitted tubular part20. The areas401to406differ by their knit schemes, their colors, their elasticity or their stiffness. The areas406thus correspond to knitted unidirectional reinforcement elements reinforcing the medial and lateral parts of the upper400.

The flattening opening shown in the figures is a longitudinal opening. Of course, the opening can have the shape of a cross or another shape as long as the shape of this opening allows the flattening of the knitted tubular part include therein.