WO1995027416A1

WO1995027416A1 - Reinforced sole, particularly for sports shoes

Info

Publication number: WO1995027416A1
Application number: PCT/EP1995/001265
Authority: WO
Inventors: Massimo Foffano; Cecilia Pamio
Original assignee: Nordica S.P.A.
Priority date: 1994-04-12
Filing date: 1995-04-06
Publication date: 1995-10-19
Also published as: ITTV940038A0; ITTV940038A1; IT1274345B

Abstract

A reinforced sole, particularly for sports shoes includes essentially a reinforcement frame (4) that can be embedded within the sole (3) and a plurality of holes (8) provided where the sole of the foot rests. These regions are the resting points of the heel and of the first and fifth metatarsal bones. Advantageously, the reinforcement frame also has strengthening ribs that connect the resting regions.

Description

REINFORCED SOLE, PARTICULARLY FOR SPORTS SHOES Technical Field

The present invention relates to a reinforced sole, particularly for sports shoes. Background Art

Sports shoes with internal reinforcements are known. Austrian patent No. 6127/74, for example, discloses a ski boot composed of two parts and having an articulation between a lower part of the upper and a cuff that surrounds the foot in the region above the malleolus and optionally in the malleolar region. Said articulation can be turned over in the longitudinal direction of the boot and consists of a leaf spring that reaches at least beyond the rear region of the heel. The leaf spring connects the cuff to the lower part of the upper and is surrounded by a second leaf spring at the rear.

However, this solution has drawbacks: the leaf springs must in fact be connected to the sole, to the upper, and to the cuff, and accordingly require additional operations to form the shoe.

Furthermore, the first leaf spring makes the sole even more rigid, and therefore all impacts are transmitted to the foot and to the user's leg, leading to fatigue during sports practice.

European patent No. 0030839 discloses a safety shoe at the sole whereof a protective plate is embedded; said plate is not flat and is connected, at the front, to a rigid toe unit and to a curved rigid element located so as to protect the metatarsal region. This solution is essentially meant for special uses, such as for example in mines, that require both overall protection of the foot, in the sense of protecting it by surrounding it in the instep region, in the toe region, and in the sole region, and good flexibility; however, the size of the plate, and its consequent weight, increases fatigue during use and also worsens fit.

Furthermore, this solution is constructively complicated and expensive.

Furthermore still, the rigid element in the sole causes ground impacts to be mostly transmitted directly to the foot, with consequent additional fatigue during use of the shoe.

European patents Nos. 0373336 and 0044549 disclose soles in which variously shaped reinforcements, such as blades or plates, are embedded; however, even these solutions have the above-mentioned drawbacks, especially transmission of the ground impacts of the sole to the foot, causing consequent fatigue for the user. Disclosure of the Invention

The aim of the present invention is to solve the described technical problems by eliminating the drawbacks of the prior art by providing a sole that has optimum reinforcement characteristics and, at the same time, allows optimal cushioning of ground impacts, so as to limit fatigue for the foot and the leg.

Within the scope of this aim, an important object is to provide a sole that is reliable and safe in use and has low manufacturing costs.

This aim, these objects, and others which will become apparent hereinafter are achieved by a reinforced sole, particularly for sports shoes, characterized in that it comprises a reinforced frame embedded in said sole and having a plurality of holes. Brief Description of the Drawings

Further characteristics and advantages of the invention will become apparent from the detailed description of a particular but not exclusive embodiment, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a partially sectional side view of a sports shoe having a sole according to the invention; figure 2 is a cross-sectional view, taken along the plane II-II of figure 1; figure 3 is a schematic view of the shape of the foot resting on the sole; figure 4 is a top view of the reinforcement frame; figure 5 is a sectional view, taken along the plane V-V of figure 4; figure 6 is a sectional view, taken along the plane VI- VI of figure 4; figure 7 is a sectional partial view, taken along the plane VII-VII of figure 4; figure 8 is a sectional partial view, taken along the plane VIII-VIII of figure 4; figure 9 is a sectional view, taken along the plane IX- IX of figure 4; figure 10 is a top view, similar to figure 4, of a reinforcement frame according to a further embodiment of the invention. Ways of carrying out the Invention

With reference to the figures, the reference numeral 1 designates a sports shoe constituted by an upper 2 associated with a sole 3.

A reinforcement frame 4 is embedded within said sole and can be made of plastics filled with fibers, plastics, aluminum, or other appropriate material.

The reinforcement frame 4 has a plurality of longitudinal reinforcement ribs 5 and also has through holes formed at the regions where the sole 6 of the foot 7 rests.

In the particular embodiment shown in figure 4, three holes, designated by the reference numerals 8a, 8b, and 8c, have been considered; said holes are respectively provided at the region 9 where the heel 10 rests, at the region 11 where the first metatarsal bones 12 that form the little toe rest, and at the region 13 where the fifth metatarsal bones 14 that form the big toe rest.

The holes preferably approximately affect the points that connect the respective metatarsal bones and the phalanxes 15.

Advantageously, each hole 8a, 8b, and 8c, is mutually connected by adapted ribs 16a, 16b, and 16c that further increase the torsional and flexural strength of the reinforcement frame 4.

A region for absorbing impacts during walking is formed at the holes 8a, 8b, and 8c during the manufacture of the sole, for example by means of processes that vulcanize the rubber part and subsequently pour polyurethane or other thermoplastic material around the reinforcement frame.

Other processes that can be used to manufacture the sole may include injection-molding. The rubber or plastic material of said sole will thus fill and pass through the holes provided in the reinforcement frame, which is placed beforehand in the mold of the sole. Accordingly, a sole reinforcement is obtained that simultaneously allows to cushion all the shocks caused by impacts with the ground during walking by means of the holes 8a, 8b, and 8c at the heel resting region 9, at the first metatarsal bone resting region 10, and at the fifth metatarsal bone resting region 13.

The continuity of the reinforcement frame, and therefore its rigidity, are in fact interrupted at the very points where the contact pressure of the sole of the foot on the ground is highest, since in these points the softer material that constitutes the sole has a continuity in a vertical direction and therefore along the shock transmission directrix, allowing to effectively cushion the impact.

The holes may of course have the desired size and shape according to the specific resting point of the user's foot.

Said holes can thus be preferably provided within the area 17 where the sole of the foot rests on the ground during walking.

It has thus been observed that the invention has achieved the intended aim and objects, a shoe having been obtained that comprises a sole reinforcement which in addition to protecting the sole of the foot allows most of all to cushion the forces applied to the sole while walking at the points of contact of the foot inside said sole.

In any case, the shoe thus obtained also has optimum torsional strength by virtue of the ribs. The optional vulcanization of the reinforcement frame inside the sole, or its injection-in-place together with the plastic material that constitutes the sole, allows to obtain said sole in its final configuration with low costs and also allows to replace the reinforcement frame if it is necessary to resole the shoe, thus regenerating the technical characteristics of said shoe.

The number of holes and their position can of course also be the most convenient according to the specific requirements. For example, figure 10 shows a reinforcement frame 104, according to a further embodiment of the invention, having ribs 116 and a plurality of holes 108 of different diameters.

Claims

1. Reinforced sole, particularly for sports shoes, characterized in that it comprises a reinforced frame embedded in said sole and having a plurality of holes.

2. Reinforced sole according to claim 1, characterized in that said holes are formed at the heel resting region and at the region where the first and fifth metatarsal bones rest.

3. Reinforced sole according to claim 2, characterized in that said reinforcement frame has ribs connecting at least two of resting regions of the heel, of the first metatarsal bones, and of the fifth metatarsal bones.

4. Reinforced sole according to one or more of the preceding claims, characterized in that said holes are formed approximately at the regions that connect said first and fifth metatarsal bones and the respective phalanxes.

5. Reinforced sole according to one or more of the preceding claims, characterized in that said holes are formed at the region where the sole of the foot rests during walking.

6. Reinforced sole according to claim 1, characterized in that said reinforcement frame has ribs.