The invention relates to a shoe, especially to a sports shoe, with a shoe upper and a sole connected with the shoe upper, wherein the shoe comprises a central fastener for lacing the shoe at the foot of a wearer, wherein the central fastener comprises at least one tensioning element which is arranged on or in a region of the shoe upper by which a lacing force can be exerted onto the region of the shoe upper and at least one gear element driven by at least one electric motor, wherein a section of the tensioning element can be pulled against a fixed location of the shoe by means of the gear element to create a tensioning force for lacing the shoe at the foot of the wearer.

A shoe of the generic kind, i. e. with an electric motor operated central fastener is known from DE 298 17 003 Ul. Here, a tensioning roller is electric motor operated for winding of a tensioning element being a cable so that the shoe can be laced and de-laced automatically and electrically respectively. Detrimentally, the pre-known central fastener (or central closure system) requires a certain space which is not always available at a shoe, especially at a sports shoe. Thus it is an o b j e c t of the present invention to propose a shoe with a central fastener which has a very low demand with respect to the required space. Thus, it is aimed that the central closure system is very compact. The s o l u t i o n of this object according to the invention is characterized in that the section of the tensioning element is a strap which comprises a gearing or a profile, wherein the gear element comprises a worm which engages into the gearing or profile to pull the strap in a translational direction at the rotation of the worm.

The gearing is preferably realized by a plurality of parallel grooves which are machined, especially punched, into the strap.

The tensioning element comprises preferably at least one laminar part which is arranged in the plane of the surface of the shoe upper, wherein the laminar part has a thickness measured perpendicular to the surface of the shoe upper and a width measured in the plane of the surface of the shoe upper, wherein the width is at least 10 times as big as the thickness, specifically preferred at least 25 times as big as the thickness. That is, the tensioning element is at least partially made of a quite thick material.

The laminar part comprises in this case preferably a central section which is arranged in the instep region of the shoe. The central section is preferably connected with at least one lateral section and at least one medial section, wherein the at least one lateral section and the at least one medial section run down from the central section to the sole.

A preferred embodiment of the invention proposes that two lateral sections and two medial sections are arranged, wherein a part of the central section and the two lateral sections and a part of the central section and the two medial sections form a triangular structure on the surface of the shoe upper.

The at least one lateral section and the at least one medial section merge preferably into each one strap. In this case it can be provided that two worms are arranged which each engage into one gearing or profile of the strap.

The tensioning element is preferably made of a thin panel sheet made of metal. The thickness of the panel sheet is preferably less than 2.0 mm, specifically preferred less than 1.0 mm. The panel sheet is preferably made of light metal, especially of aluminium or magnesium.

A switch for controlling the central fastener can be arranged in the central section. Preferably, the switch is made of unitary design with the tensioning element (i. e. as a one-piece element). The switch is preferably a contact sensor which is sensitive to a wipe movement of a finger of the user of the shoe onto an actuation surface of the contact sensor.

The control of the system can alternatively also be carried out by means of a mobile phone in which a respective app is loaded. In this case the user of the shoe can activate the lacing and de-lacing process by using his or her mobile phone.

The gear element and the electric motor are preferably arranged in the sole of the shoe.

As the section of the tensioning element is a strap which comprises a gearing or a profile, in which the worm of the gear element engages (i. e. meshes) it is possible to create a very compact design for the central fastener. In the drawings embodiments of the invention are shown.

Fig. 1 shows a perspective view of a shoe which is provided with a central fastener according to a first embodiment of the invention,

Fig. 2 shows an explosion view of a part of the central fastener, namely of a gear element with a worm and an electric motor and a strap with a gearing in which the worm meshes during intended use,

Fig. 3 shows a section through the shoe perpendicular to its longitudinal axis showing the central fastener (without electric motors),

Fig. 4 shows the side view of the shoe according to a second embodiment of the invention,

Fig. 5 shows the side view of the shoe according to a third embodiment of the invention,

Fig. 6 shows a perspective view of the shoe according to a fourth embodiment of the invention,

Fig. 7 shows a perspective view of the shoe according to a fifth embodiment of the invention,

Fig. 8 shows the side view of the shoe according to a sixth embodiment of the invention, Fig. 9 shows the side view of the shoe according to a seventh embodiment of the invention,

Fig. 10 shows the side view of the shoe according to an eighth embodiment of the invention, and

Fig. 11 shows the side view of the shoe according to a ninth embodiment of the invention. In figures 1 to 3 a first embodiment of the invention is shown. A shoe 1 has a shoe upper 2 and a sole 3 connected with the shoe upper 2. The lacing of the shoe at the foot of a wearer is carried out by a central fastener 4.

The central fastener 4 tensions a tensioning element 5 so that a tensioning force can be exerted to the shoe upper 2 and thus to the foot of the wearer.

The tensioning of the tensioning element 5 takes place by means of a gear element 6 (and more specifically by two gear elements 6 in the present embodiment). The gear element 6 is shown in figure 2 in an explosion view. It comprises an electric motor 7 which drives a worm 11. A section 8 of the tensioning element 5 is designed as a strap in which a gearing or profile 10 is machined. In the present case according to figure 2 the gearing 10 is established by a plurality of parallel grooves which are punched into the strap 8.

Worms 11 of the mentioned kind are well known in the art. Reference is made to common worm gears consisting of a driving worm and a driven worm wheel. Such a worm which can mesh with the grooves in the strap 8 is suitable for the present solution. The electric motor 7 as well as the worm 11 are arranged at a fixed location 9 of the shoe and more specifically within the sole 3. Accordingly, when the electric motor 7 rotates the worm 11 and when the worm 11 meshes with the gearing 10 in the strap 8, the end of the strap 8 is moved in a translational direction T (see figure 2 and 3).

Fixed location 9 means in the above context that this is a location in the shoe against which the strap 8 is pulled at the actuation of the gear element 6. That is, while the strap 8 can be moved in translational direction T relatively to the shoe and specifically in the sole 3, the worm 11 together with the electric motor 7 is arranged stationary in the shoe 1 and specifically in the sole 3.

The strap 8 is a part of the tensioning element 5 which is made of a thin sheet metal plate which is machined according to the shape as becomes apparent from figure 1, i. e. the tensioning element 5 consists substantially of a laminar part 12.

The tensioning element 5 is thus produced from a thin material with a thickness t which is preferably below 1.0 mm. Compared with the thickness t the width w of the different sections of the tensioning element 5 (see figure 1) is substantially bigger, e. g. at least 10 times of the thickness t. Accordingly, the tensioning element 5 comprises certain strip-like sections which are arranged in the surface of the shoe upper 2 (with the width w) which have a small extension perpendicular to the surface of the shoe upper 2 (with the thickness t).

As can be seen specifically from figure 3 the laminar part 12 of the tensioning element 5 merges in the lateral and medial side of the shoe upper 2 in a lateral section 14 and a medial section 15. In the case of the depicted embodiment two strip-like lateral sections 14 and two medial sections 15 merge into the strap 8 which in turn carries the profile 10. Preferably a section of the laminar part 12 and the two strip-like lateral sections 14 as well as a section of the laminar part 12 and the two medial sections 15 form a triangular structure as becomes a parent from figure 1 (for the lateral sides of the shoe). In figure 3 it can be seen that two gear element 6 are arranged in the sole 3 of the shoe 1, wherein each gear element 6 cooperates with a strap 8 of the tensioning element 5. It should be noted that in figure 3 the two gear elements 6 are offset in a direction perpendicular to the drawing plane of figure 3. When the two electric motors 7 (not shown in figure 3) are operated simultaneously the two straps 8 are moved toward another or away from another (depending on the rotation direction of the electric motors 7) to lace or to de-lace the shoe 1.

As can be seen from figure 1 the laminar part 12 of the tensioning element 5 has a central section 13. A switch 16 is arranged in the centre of the central section 13 by which the lacing and the de-lacing of the shoe can be carried out by the wearer of the shoe by a wipe movement of a finger across the surface of the switch 16. Thus, when the two electric motors 7 (not shown) of the two gear elements 6 in figure 3 are activated the two straps 8 are pulled by the two worms 11 in the translational direction T and thus the shoe is laced at the foot of the wearer. Coming now to figures 4 to 11 different alternative embodiments of the present invention and more specifically of the tensioning element 5 are shown. As a common feature the design of the central fastener is always as described in connection with figures 1 to 3. Thus, the different embodiments of figures 4 to 11 concern the design of the tensioning element 5 only.

In figure 4 the tensioning element 5 has basically two strip-like sections which merge at the location of the strap 8 and which form a V-shaped design at the medial and at the lateral side of the shoe.

In figure 5 additionally a strip-like section is provided which runs around the heel section of the shoe to improve the lacing effect.

The embodiment according to figure 6 is similar to that one of figure 4. Additionally, some cables 17 are arranged which are connected with the tensioning element 5 and the sole 3 and which provides an additional lacing when the tensioning elements 5 is put under tension by a movement of the strap 8 by means of the central fastener 4. In figure 7 additional strip-like part of the tensioning element 5 are provided in the forefoot and the rearfoot region. Also here cables 17 are provided which span over the instep region of the shoe.

In figure 8 the tensioning element 5 is basically formed by only one strip-like section (one in the lateral side and one in the medial side of the shoe) which are connected with cables 17 which are guided in the instep region of the shoe as well as in the forefoot and in the heel region of the shoe. In figure 9 the tensioning element 5 consists basically of a single section which merges in the lateral and in the medial side of the shoe into the strap 8.

In figure 10 the single elements of the tensioning element 5 are quite thin and designed as cables which run across the instep region of the shoe and around the heel section of the same.

Finally, in figure 11 the tensioning element 5 is designed as a net-like structure made of different cables which finally are tensioned by the strap 8.

The cables 17 (being finally a part of the tensioning element 5) can be connected with another part of the tensioning element 5 for example by soldering. As a preferred manufacturing method of the whole tensioning element 5 (with straps 8 but without cables 17) it is suggested to cut out the required shape of the tensioning element 5 from a thin (e. g. rectangular) metal plate by punching, laser cutting, electron beam cutting or the like. By this method also the grooves 10 can be cut out efficiently. This allows an economic production of the tensioning element 5.

It is also possible to produce the tensioning element 5 by connecting several parts together. So, for example the straps 8 can be produced separately and then fixed to the rest of the structure of the tensioning element 5.

Not shown in the figures are a battery and wires which are of course necessary for the operation of the electric motors 7. Reference Numerals:

1 Shoe

2 Shoe upper

3 Sole

4 Central fastener

5 Tensioning element

6 Gear element

7 Electric motor

8 Section of the tensioning element (strap)

9 Fixed location of the shoe

10 Gearing / profile

11 Worm

12 Laminar part of the tensioning element

13 Central section

14 Lateral section

15 Medial section

16 Switch

17 Cable

T Translational direction

t Thickness

w Width