ES2768772T3 - Footwear with removable soles - Google Patents

Abstract

Footwear (1) adaptable in height such that it comprises: - a flexible sole (2) comprising a means of fixing in the front part (4) of the flexible sole and a means of fixing in the back part (6) of the sole flexible, as well as a reed (10); - at least one first rigid base sole (3 ') interchangeable with a second rigid base sole (3), the second rigid base sole having a heel (11) of a different height from that of the first rigid base sole (3 ), each rigid base sole (3.3 ') extending in use along the entire length of the foot and comprising a fixing means in the front part (7) of the rigid sole complementary to the fixing means in the front part of the flexible sole (4) and a fixing means at the back (9) of the rigid sole complementary to the fixing means at the back (6) of the flexible sole, at least one of the rigid base soles comprising a heel at least 3 cm high.

Description

DESCRIPTION

Footwear with removable soles

Object of the invention

The present invention relates to low-heeled footwear that can be quickly converted into high-heeled footwear and vice versa, through a system of removable soles.

State of the art

In the field of footwear, there are a large number of patents that refer to footwear with interchangeable heels in order to convert low-heeled shoes into high-heeled shoes.

US patent 5,675,916 describes a shoe with interchangeable heels in which the heel is threaded at the rear of the shoe.

However, in these previous patents, the end of the shoe heel is provided with mounting means on which heels of different heights can be fixed.

Apart from the lack of aesthetics of footwear due to the presence of these fixing means, said device presents the following functional problem. When changing from a low heel to a high heel (or vice versa), the change in the curvature of the shoe that must adapt to the curvature of the foot is not taken into account. This is particularly problematic for closed, rigid footwear.

Indeed, when going from a low heel where the grip on the ground is optimal to a high heel, the shoe will lean forward, the grip on the ground at the front of the shoe is no longer optimal. Conversely, when going from a high heel where grip on the ground is optimal to a low heel, the shoe will tilt up, lifting the front of the shoe, curving it. In the two cases represented, the adherence to the ground is not optimal for at least one heel position either high or low.

US patent 5,347,730 has proposed a solution to this problem. Refers to a device suitable for converting low-heeled footwear into high-heeled footwear. In this device, the low heel is permanently attached to the shoe and comprises means for attaching a removable high heel. This document describes an extensible band built into the sole of the shoe that, when the shoe is changed between a high and low heel, can be manually adjusted by flexing the sole at a low or high heel level so that the shaft maintains the shoe shape corresponding to the state of the heel either high or low.

Patent application US 2014/0215852 A1 proposes a comfortable low-heeled shoe whose flexible leather sole allows flexing of the shoe and comprises a reinforcement at the place of curvature in order to support the wearer's plantar vault. The heel comprises a hitch system complementary to that of a removable high heel. Patent application US2014 / 0137436 also proposes a high-heeled shoe with interchangeable base soles.

Finally, it is necessary to be able to adapt the shape of the shaft and sole in contact with the sole of the foot with the curvature, depending on the height of the heel, in the case of a high heel, it is also necessary to maintain significant rigidity of the sole to avoid rotation of the heel in relation to the vertical. The prior art does not allow these two imperatives to be resolved simultaneously.

Aims of the invention

The present invention tries to provide footwear that allows to go from a low heel to a high heel without presenting the drawbacks of the state of the art.

The footwear of the invention has the technical characteristics that allow the curvature of the footwear to be adapted to the curvature of the foot when going from a low heel to a high heel or vice versa, ensuring good adherence to the ground and respecting the morphology of the foot. whatever the height of the heel.

The footwear of the invention must also allow sufficient support for the plantar vault and avoid rotation of the heel.

Main characteristic elements of the invention

A first aspect of the present invention relates to height-adjustable footwear comprising:

- a flexible sole comprising a fixing means at the front of the flexible sole and a fixing means at the rear of the flexible sole as well as a shank; and

- at least a first interchangeable rigid base sole with a second rigid base sole, the second rigid base sole presenting a heel of a height different from that of the first base sole rigid, each rigid base sole extending the entire length of the foot and comprising a means of fixation at the front of the rigid sole complementary to the means of fixation at the front of the flexible sole and a means of fixation at the rear of the rigid sole complementary to the fastening means at the rear of the flexible sole, at least one of the rigid base soles comprising a heel of at least 3 cm high, preferably at least 5 cm high.

The preferred embodiments of the invention further comprise in combination one or more of the following features:

- at least one of the rigid base soles comprises a lining, preferably comprising a material selected from the group consisting of metal, wood and thermosetting resin, preferably fiber-reinforced, preferably glass or carbon;

- the first rigid base sole has a different curvature from that of the second rigid base sole; - the flexible sole further comprises an attachment means essentially in the center of the sole and the rigid base sole comprises an attachment means essentially in the center of the rigid sole complementary to the attachment means essentially in the center of the flexible sole. Preferably, these fastening means essentially in the center of the sole are, interchangeably, a male fastener capable of sliding within a complementary channel. Furthermore, they extend over 5 to 80% of the sole length, preferably over 10 to 50%;

- the flexible sole fixing means and the rigid base sole fixing means further comprise a connecting element suitable for joining the corresponding fixing means to each other;

- the fixing means at the front of the flexible sole is a male flange on the periphery of the flexible sole capable of sliding in a female notch of the fixing means at the front of the rigid sole. Preferably, the male bead and its female notch insert extend over at least 5 cm from the front of the sole;

- the fastening means at the back of the flexible sole and the fastening means at the back of the rigid sole are a complementary elastic clip fitting system;

- the thickness of the flexible sole is between 1 and 10 mm;

- the thickness of the rigid base sole is between 1 and 150 mm;

- the flexible sole is an orthopedic sole;

- the shoe further comprises a protective sole or an orthopedic sole;

the shoe is closed and the upper preferably comprises an expandable element at a pivot point between the part of the rigid sole that adheres to the ground and the part that comes off of it;

- the rigid base soles preferably comprise partial shank elements, preferably at the back, in order to provide greater support for the heel, and possibly the ankle. Brief description of the figures

Figure 1 represents profile views of open footwear according to the invention in which a flexible sole comprising the upper is combined with a sole with a rigid base that alternately comprises a high heel (figure 1A) or a low heel (figure 1B).

Figure 2A represents an elevation view of a shoe of the invention in which the upper is not shown. The soles are fixed to each other by means of complementary fixing means located at the front of the sole and at the rear. A sectional view along the axis A-A is represented in figure 2B. Figure 3A represents an elevation view of a flexible sole according to the invention comprising fixing means at the front and at the rear of the sole. A sectional view along the axis B-B is represented in figure 3B.

Figure 4A represents an elevation view of a rigid base sole according to the invention, comprising fixing means at the front and at the rear of the sole. A sectional view along the C-C axis is shown in figure 4B.

Figure 5A represents an elevation view of a shoe of the invention in which the upper is not shown. The soles are fixed to each other by means of fixing means at the front, center and rear of the sole. A sectional view along the D-D axis is shown in Figure 5B and a sectional view along the D'-D 'axis is shown in Figure 5A.

Figure 6A represents an elevation view of a flexible sole according to the invention, which includes fixing means at the front, center and rear of the sole. A sectional view along the E-E axis is represented in figure 6B.

Figure 7A represents an elevation view of a rigid base sole according to the invention, comprising fixing means at the front, center and rear of the sole. A sectional view along the FF axis is shown in figure 7B.

Figure 8 represents profile views of closed footwear type according to the invention. The shank comprises an elastic element at the level of the curvature of the shoe. The flexible sole that includes the upper is combined with a rigid base sole that alternatively includes a high heel (upper figure) or a low heel (lower figure).

Detailed description of the invention

Definitions

The sole comprises the different elements that are between the foot and the ground.

By "essentially in the center" is meant in the present invention a central area, comprised within the arch of the shoe, in the area normally out of contact with the ground, located between the heel at the back and the front contact area with the ground.

The "base sole" is the part in contact with the ground. It is classically fixed according to the case with the first mounting (welded), the intercalation sole or directly to the shank (moccasin mounting). In the framework of the invention, the base sole corresponds to the rigid base sole. It is removably fixed in the first assembly. By "rigid" is meant that the sole is made of a material that gives it a certain stiffness as opposed to a flexible type sole. The stiffness of a material depends on its Young's modulus. Young's modulus (MY) is the mechanical stress that would produce an elongation of 100% of the initial extension of a material (would therefore double the length), if it could actually be applied. In its embodiment, the material would permanently deform, or break, before this value was reached. A material whose Young's modulus is very high is called rigid. Steel (MY = 200 Gpa or gigapascal), diamond (MY = 1000 Gpa), are very rigid materials, wood (MY of oak = 12 Gpa) is less. Plastic and organic materials, foams are generally not very rigid, they are said to be flexible, elastic or flexible (for a bending force). The rigid base sole is preferably made of a rigid plastic or composite material possibly enriched with carbon fiber in order to thereby increase stiffness (Young's modulus for high strength carbon fiber = 240 Gpa). The base sole may also be made of wood. The "main mount" is the part on which the pole is mounted. In the framework of the invention, the main mounting corresponds to the flexible sole. The flexible sole is preferably made up of a flexible material such as natural or synthetic rubber (MY between 0.007 and 0.004 Gpa), polyethylene (MY between 0.2 and 0.7 Gpa), polyurethane (MY between 0.002 and 0.02 Gpa).

Within the framework of the invention, a material can be considered as rigid if its Young's modulus is greater than 1 Gpa and flexible if its Young's modulus is less than 1 Gpa. Preferably, the Young's modulus of the rigid sole is greater than 5 Gpa. In particular, the lining preferably has a modulus greater than 5 GPa, while the rest of the base sole has a more flexible modulus (for example, between 1 and 5 GPa).

The "main property" is a thin sheet of leather that is glued onto the main mount and is quick to finish. It is in direct contact with the foot. The manufacturer's or dealer's name and size are often engraved on it. A thin layer of foam can be inserted underneath to improve comfort. When it only covers the back of the shoe, it is called the heel.

The "vira" is a small leather band that is sewn or glued on the contour of the shoe and that covers the lower part of the shaft with a few millimeters. It can be decorative with a fantasy trimmed edge. In dress shoes, when it only forms a relief to hide the junction of the shaft and sole, it is called a shoulder brace.

The «enfranque» is a cane made of wood (so that it does not rust), metal or resin that maintains the curve of the arch towards the front of the heel. On some very tall models this can be very dense. It has a very important role in the comfort of footwear.

In particular, the rigid sole of the invention must allow the high heel to be kept perfectly vertical, in order to avoid twisting of the ankle, or, more generally, a fall by the user. The rigid sole must therefore simultaneously prevent twisting movements and bending movements. For this, the rigid sole of the invention preferably comprises a lining.

The "heel" provides the height at the back of the shoe.

The "cap" is the thin layer of rubber or plastic that is under the heel (for women) or for the back of the heel (for men) and is meant to be changed when worn.

The "shank" is the outer part of the shoe that covers the foot. It is made up of several parts.

The "instep" or galosh is the piece of skin or tissue that is on the front of the foot.

The "buttresses" are the inner and outer parts of the shoe.

The «flashing» is the narrow leather band that hides, if necessary, the seam that joins the two buttresses.

The "closing means" adorn the upper to allow you to pass your foot into the shoe and then keep it in place. They therefore have a function of comfort, but also aesthetics because they provide each shoe with a different style.

Figure 1 shows profile views of open shoes 1 according to the invention in which a flexible sole 2 comprising a shank 10 (consisting of an instep 17 and a buttress 18) is alternatively combined with a rigid base sole 3.3 'comprising a high heel 11 (figure 1 A) or low (figure 1B). The 3.3 'rigid sole is removable and covers the entire length of the foot. It adapts perfectly to the curvature of the foot and the grip at ground level is optimal.

Figure 2A represents an elevation view of a shoe of the invention according to a first embodiment. The reed is not shown so that the fixing means are visible. The soles 2, 3 are fixed to each other by means of complementary fixing means located at the front of the sole 4, 7 and at the rear 6, 9. A sectional view along the AA axis is represented in the figure 2B.

The flexible sole 2 shown in FIG. 3A comprises a first fixing means at the front of the sole 4 and a first fixing means at the rear of the sole 6. A sectional view along the BB axis is shown in the figure 3B.

The rigid base sole 3 shown in FIG. 4A comprises a first fixing means at the front of the sole 7 and a second fixing means at the rear of the sole 9. A sectional view along the CC axis is shown in figure 4B.

The fixing means 4 located at the front of the flexible sole 2 consists, for example, of a male flange 14 that covers the contour of the sole capable of sliding in a female notch 15, second complementary fixing means 7 of the sole rigid 3.

The complementary fixing means 6, 9 located at the rear of the soles 2, 3 correspond, for example, to an elastic clip-on system. This is the case, for example, of a rounded element that is located on the flexible sole 2 that is suitable for fastening in a complementary notch that is on the rigid base sole 3. The fixing means 6, 9 can also comprise an element of junction 19 that joins them together. An example of connecting element 19 is represented in Figures 4A and 4B. Its lower part slides into a notch in the rigid sole 3 and its upper part is fastened in a complementary notch located in the flexible sole 2.

Figure 5A represents a top view of a shoe of the invention according to a second embodiment. The reed is not shown so that the fixing means are visible. The soles 2, 3 are fixed to each other by means of complementary fixing means located at the front of the sole 4, 7, essentially in the center 5, 8 and at the rear 6, 9. A sectional view along the axis D'-D 'shows that the first fixing means 5 located essentially in the center of the flexible sole 2 is, for example, a male fixation 12 able to slide in a channel 13, second complementary fixing means 8 of the sole rigid 3. A sectional view along the DD axis is shown in figure 5B.

The flexible sole 2 shown in FIG. 6A comprises a first fixing means at the front of the sole 4, a first fixing means at the center of the sole 5 and a first fixing means at the rear of the sole 6 A sectional view along the axis EE is represented in figure 6B.

The rigid base sole 3 shown in FIG. 7A comprises a first fixing means at the front of the sole 7, a second fixing element at the center of the sole 8 and a second fixing means at the rear of the sole. sole 9. A sectional view along the FF axis is shown in figure 7B.

Figure 8 represents profile views of closed shoes 1 according to the invention. The shank 10 comprises an expandable element 16 at the pivot point between the part of the rigid sole 3 that adheres to the ground and the part that detaches from it. This expandable element, composed of a polymer that has elastic properties such as an elastomer, allows the shank to be adjusted to the curvature of the foot, avoiding an excess of shank material (fold) in the presence of a high heel or a stretch that makes it brittle. presence of a low heel. The flexible sole 2 comprising the shank 10 is combined with a rigid base sole 3 alternatively comprising a high heel 11 (figure above) or a low heel (figure below).

Main advantages of the invention

The fact that the entire rigid sole is removable and not only the heel provides several advantages that are summarized below:

- The fact of having a rigid sole that covers the entire foot allows to have the hitch systems in three different places and thus improve the stability of the shoe in relation to a single heel;

- The fact of having a rigid sole that covers the entire foot allows modifying the sole design to be chosen in order to respond to functional or aesthetic demands. For example, the sole could comprise a non-slip coating in winter and a smooth coating in summer. In addition, the sole could present various colors and textures (including a compensated heel for example) in order to meet the fashion criteria of the moment.

- The invention also makes it possible to train to wear a heel for people who are not used to it and to easily move to a flat heel.

- This allows maintaining a homogeneous style despite a variation in sole height both at the heel level and throughout the sole, since the shaft is the same.

- The invention can be combined with orthopedic soles that necessarily cover the entire length of the foot. The orthopedic sole could be combined with rigid base soles that present aesthetic or functional variants;

- The removable sole allows to respect the dimensions of the foot reducing the tensions exerted on it during a height change, but also thanks to its adaptation to the inclination of the foot and its compatibility with orthopedic soles. In summary, the invention allows to respect the morphology of the foot through each desired combination.

- The fact that the entire sole is removable allows to guarantee a very good adherence to the ground regardless of the heel height.

List of reference symbols

1. Footwear

2. Flexible sole

3. (3,3 ’) Rigid base sole

4. Fixing medium at the front of the flexible sole

5. Fixing medium essentially in the center of the flexible sole

6. Fixing medium at the back of the flexible sole

7. Fixing medium at the front of the rigid sole

8. Fixing medium essentially in the center of the rigid sole

9. Fixing medium on the back of the rigid sole

10. reed

11. Heel

12. Male fixation

13. Channel

14. Male flange

15. Female notch

16. Expandable element

17. Instep

18. Buttress

19. Connecting element

Claims (14)

1. Footwear (1) adaptable in height such that it comprises: - a flexible sole (2) comprising a fixing means at the front (4) of the flexible sole and a fixing means at the rear (6) of the flexible sole, as well as a shank (10); - at least a first rigid base sole (3 ') interchangeable with a second rigid base sole (3), the second rigid base sole presenting a heel (11) of a height different from that of the first rigid base sole (3 ), extending in use, each rigid base sole (3.3 ') along the entire length of the foot and comprising a fixing means in the front part (7) of the rigid sole complementing the fixing means in the front part of the flexible sole (4) and a fixing means at the rear (9) of the rigid sole complementary to the fixing means at the rear (6) of the flexible sole, at least one of the rigid base soles comprising a heel at least 3 cm high. 2. Footwear (1) according to claim 1, characterized in that the flexible sole (2) further comprises a fixing means essentially in the center of the sole (5) and in that the rigid base sole (3, 3 ') it comprises a fixing means essentially in the center of the rigid base sole (8) complementary to the fixing means essentially in the center of the flexible sole (5). Footwear (1) according to claim 2, characterized in that the fixing means essentially in the center of the flexible sole (5) and the second fixing means essentially in the center of the sole with a rigid base (8) are, interchangeably, a male fastener (12) suitable for sliding in a complementary channel (13). Footwear (1) according to claim 2 or 3, characterized in that the first fixing means essentially in the center of the flexible sole (5) extends by 5 to 80% of the extension of the sole. Footwear (1) according to any one of the preceding claims, characterized in that the fixing means (4, 5. 6) of the flexible sole and the fixing means (7, 8, 9) of the rigid base sole they further comprise a connecting element (19) suitable for connecting the two fixing means to each other. 6. Footwear (1) according to any one of the preceding claims, characterized in that the fixing means at the front of the flexible sole (4) is a male flange (14) on the periphery of the flexible sole (2) to slide into a female notch (15) of the fastening means at the front of the rigid sole (7). Footwear (1) according to claim 6, characterized in that the male flange (14) and its female notch complement (15) extend over at least 5 cm from the front part of the sole. Footwear (1) according to any one of the preceding claims, characterized in that the fixing means on the back of the flexible sole (6) and the fixing means on the back of the rigid sole (9) are a Complementary elastic clip system. 9. Footwear (1) according to any one of the preceding claims, characterized in that at least one of the rigid base soles comprises a lining. 10. Footwear (1) according to claim 9, characterized in that the adapter flange comprises a material selected from the group consisting of metal, wood and thermo-hardened resin, preferably reinforced by fibers. 11. Footwear (1) according to any one of the preceding claims, characterized in that the flexible sole (2) is an orthopedic sole. 12. Footwear (1) according to any one of the preceding claims, characterized in that it further comprises a protection sole or an orthopedic sole. 13. Footwear (1) according to any one of the preceding claims, characterized in that the footwear is closed. 14. Footwear (1) according to claim 13, characterized in that the upper (10) comprises an expandable element (16) with a pivot point between the part of the rigid sole (3) adherent to the ground and the part that comes off of the same.