JPS63194602A - Shoe sole of sports shoes - Google Patents

Abstract

1. A shoe bottom, in particular for sports shoes, which in the shank (5) has weak locations (6, 7) for reducing the torsional stiffness about an axis extending substantially in the longitudinal direction of the shoe, in order to permit twisting, which is adapted to the natural movement of the foot, of the front sole portion (3) relative to the rear sole portion (4), about said axis, characterised in that the shank (5) of the shoe bottom (1, 2) is stiffened against bending about an axis extending transversely with respect to the longitudinal direction of the shoe by a striplike or rod-like stiffening element (9) which is directed in the longitudinal direction of the shoe.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention accommodates the natural movement of the foot by providing a weakened section in the shank to reduce torsional stiffness about the generally longitudinal axis of the shoe. It relates in particular to a sole of a sports shoe, in which the front sole part is twisted relative to the rear sole part about said axis.

(Conventional technology and its problems) The area near the cuneiform bone, that is, the upper part of the shank of the sole of the shoe, between the front of the foot and the heel, is an axis that exists approximately in the longitudinal direction of the foot during natural lateral sway of the foot. A twisting action occurs at the center. Taking this torsional movement into account, it is biomechanically advantageous to intentionally create a weakened section in the shank of the shoe's sole, allowing the front sole to twist relative to the rear around an axis that runs approximately in the longitudinal direction of the shoe. It is known (German Patent Specification No. 804.901). Such a weakened section is achieved by reducing the thickness of the sole or the shank of the sole, but it is preferable to leave a central protrusion extending approximately in the longitudinal direction of the shoe (German Publication). Specification DE
-AS 1485804) or four parts extending inwardly from the side edges of the sole and filled with a less rigid filler material.

A weakened section to reduce the torsional stiffness of the shank of the sole also necessarily results in a reduction in the bending resistance of the sole about the transverse axis. This also uses the above-mentioned idea to create a wedge-shaped longitudinal sole to prevent the sole from wearing out at the shank of the shoe with the heel member, and this design provides a solid support surface for the shank of the foot. It was proposed that it be established. However, especially in the case of sports shoes, the fundamentally desirable torsional performance of the front sole part relative to the rear sole part does not allow the sole to flex due to the torsion of the shank part, but can easily bend in this part. It has been found that this results in inadequate guidance and retention of the foot. The reason is that the foot has excessive free movement in the metatarsal region. This is especially important when walking or hiking, running wildly, jogging, etc., and when the runner's foot hits unavoidable bumps, the lateral stability is particularly important. It becomes noticeable when it is lacking.

The invention therefore seeks to provide a sole of the aforementioned type that is able to guide and hold the foot well without adversely affecting the desired torsion relief between the front and rear sole sections. The purpose is

(Means for Solving the Problems) The above object is achieved according to the invention by strengthening the shank of the shoe sole by means of a reinforcing device so that it does not bend around an axis extending transversely to the longitudinal direction of the shoe.

According to the invention, therefore, the shank of the sole is reinforced by a reinforcing device so that it does not bend about an axis transverse to the longitudinal direction of the shoe, the increase in bending resistance in this case being particularly pronounced at the convex sole. It is related to the bending movement that occurs when the shoe sole bends downward, that is, toward the ground contact side of the sole.

It is particularly advantageous to keep the reinforcement device, which should have torsion resistance and extend in the longitudinal direction of the shoe, close to the ground side of the sole. This element need not have any bending strength. The reason for this is that the reinforcing effect of the sole is obtained by the inextensibility or only slight extensibility of the tensile resistance element and by its placement under the "neutral bending fibers" of the sole. It is a significant advantage that the tensile resistant and, for example, strip-shaped element has no torsional rigidity of its own and therefore does not have an equally negative effect on the desired torsional performance of the front bottom part as compared to the rear bottom part. Therefore, by using such a tensile resistance member, the bending strength of the shank of the sole can be controlled within a wide range without affecting the torsional rigidity of the shank of the sole. Another important effect is that the reinforcing device (which has its own bending strength)
Compared to steel shank springs, for example), the reinforcement effect of the tension resistance device can be considerably reduced, which is important in sports shoes. There are tensile strength and almost inextensible, high-strength and very light materials such as metal wires, carbon and glass fibers, plastic wires and strip-like elements made of such materials.

In a particular embodiment of the invention, the zone of weakness that reduces the torsional stiffness in the shank of the sole extends laterally or diagonally (sloping forward or backward) medially from the edge of the sole in the longitudinal direction of the shoe. It is a recessed part extending to a protruding part. The protrusion extends approximately centrally between the side edges of the sole.

Its shape is such that the tensile resistant element extends along the projection. According to this configuration, when the shoe sole is made of plastic material, as is customary, the tensile resistance element is embedded in the projection on its underside. The element can also be provided along the free lower surface of the protrusion, in which case abrasion soles fixed to the front sole part and the rear sole part do not bring the tensile resistance element into direct contact with the ground. In this way, the tensile resistance element is placed very close to the ground side of the sole.

Even if the reinforcing device is made by the above-mentioned tensile resistance element, it is embedded in the sole of the shoe over its entire length, thus transmitting forces over its entire length and providing a reinforcing effect. However, this is not always necessary in the case of reinforcements that are both resistant to bending as well as reinforcements that are slightly resistant to tension, and it is important that their ends are suitably and securely fixed to the sole of the shoe. It becomes a point. For this purpose, it is advantageous to fix the anchoring insert at the end of the reinforcing device, for example by embedding it directly in the sole of the shoe. The anchoring insert is shaped to resist movement in the longitudinal direction of the shoe in response to forces acting on it as the sole rolls.

Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

(Example of implementation) The illustrated outer sole, which together with an inner sole (not shown) forms the sole of the shoe, essentially consists of an intermediate sole 1 made of a foamed plastic material, such as polyurethane, which contacts the ground. It has a contoured wear sole 2. The outsole is subdivided into a front sole part 3 and a rear sole part 4 of the arch part or shank 5. The sole is subdivided into two recesses 6 and 7 extending inward from the outer edge and the inner edge, respectively, and inclined diagonally forward.

As shown in FIG. 3, the recesses 6, 7 extend within the sole to more than half of its height. Between the mutually facing ends of the recesses 6, 7, said midsole 1 remains constant in its thickness, thus providing a projecting portion 8 passing approximately through the longitudinal center of the sole.

Due to the presence of said recesses 6, 7, the front bottom part 3 is torsionally "uncoupled" with respect to the rear bottom part 4. In other words, the front sole part 3 can be twisted relative to the rear sole part 4 about the substantially longitudinal axis of the projecting part 8, and this torsion is similar to that of a human foot when it is swaying from side to side. corresponds to the natural movement of the vehicle and therefore assists in this rolling.

A reinforcing element 9 is embedded in the midsole 1. The reinforcing element 9 is made of a plastic wire 91 which is strong in tension and has low elongation (for example made of nylon) and is connected in parallel to form a flat strip, and a mooring insert fixed to the end of the wire 91. It has 92.93. A plastic wire 91 having a diameter of, for example, 1.5 mm is fixed to a mooring insert 92, 93, preferably made of plastic material, for example by being implanted directly therein. Furthermore, the plastic wires 91 are connected to each other along their entire length.

The mooring inserts 92,93 are plate-shaped (FIG. 2) and have transverse legs 94. The anchoring inserts 92,93 are provided with holes 95 through which the material of the midsole 1 can flow during the molding or shaping operation to embed the anchoring inserts in the sole.

As shown in FIG. 2, the underside of the protruding portion 8 along which the plastic wire 91 extends is located above the ground side of the wear sole 2. In the illustrated embodiment, the wear sole 2
has an exposed interruption or hole IO of plastic wire 91 in both parts of the sole, i.e. in both the front sole part 3 and the rear sole part 4. This ensures that when the front bottom part 3 is twisted relative to the rear bottom part 4, said strip formed by the plastic wire 91 is bent. However, the hole 10 is not necessary;
The reinforcing element 9 and in particular the plastic wire 91 are
In order to protect the wire 91 from damage, it can be completely covered by the wear sole 2.

From the above explanation, the following becomes clear. The bending strength of the outsole about a transverse axis extending perpendicular to the protrusion 8 can be controlled by the stretch resistance of the reinforcing element 9. If it is desired to increase the bending strength of the sole, the number of plastic wires 91 and the width of the strips formed by them can be increased. Also, in principle,
The thickness of the plastic wire can be increased, but care should be taken to avoid increasing the torsional stiffness of the sole in the shank area.

Instead of the plastic wire 91 described in the illustrated embodiment, other reinforcement devices with tensile strength can also be used. That is, a strip of glass or carbon fiber mesh, rope, or cloth may be embedded in the sole using the mooring inserts 92 and 93 in the same manner as described above. By choosing the width of the strip formed by such a fabric, the tensile strength and therefore the bending strength can be controlled within a wide range without significantly influencing the weight of the sole. However, it is also within the scope of the invention to arrange a flat metal strip with a correspondingly lower bending strength but with a significantly higher tensile strength due to its reduced thickness.

[Brief explanation of the drawing]

Fig. 1 is an exploded bottom view of a part of the sole of the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is an outside view of Fig. FIG. 3 is a side view of a portion of the bottom. 1... Middle bottom 2... Worn bottom 3... Front bottom part 4... Back bottom part 5... Shank 6.7... Four parts 8... Protruding part 9... Reinforcement Element lO... Hole 91... Plastic wire 92... Mooring insert 93... Mooring insert 94... Lateral leg portion 95... Hole

Claims (8)

[Claims] (1) The shank (5) is provided with weakened sections (6, 7) to reduce torsional stiffness about the axis extending approximately in the longitudinal direction of the shoe, and the front sole portion ( 3) is twisted relative to the rear sole portion (4) about the axis.
, 2), the shank (5) of the sole (1, 2)
) is reinforced by a reinforcing device (9) to prevent it from bending about an axis extending transversely to the longitudinal direction of the shoe. (2) The reinforcing device is a tensile-resistant element (91) extending in the longitudinal direction of the shoe and anchored to the sole (1, 2) near its ground contact side. 1. The sole of the shoe according to 1. (3) The tensile-resistant element (91) is in the form of a strip, and the ends of the element (91) are fixed to the sole by means of mooring inserts (92, 93). The sole of the shoe according to item 2. (4) The weakened sections for reducing torsional rigidity are recesses (6, 7) extending laterally or diagonally inward from the edge, and the recesses (6, 7) extend in the longitudinal direction of the shoe in the sole. 4. Shoe sole according to claim 2 or 3, characterized in that the tensile-resistant element (91) reaching the projecting part (8) is extended by the projecting part (8). (5) The element (91) extends along the free lower surface of the protrusion (8).
The sole of the shoe as described. (6) The shoe sole according to any one of claims 2 to 5, wherein the tensile-resistant element is formed of a rod or wire made of metal, plastic material, carbon fiber, glass fiber, or the like. (7) The shoe sole according to claim 6, characterized in that the rods or wires are arranged parallel to each other and connected to each other, for example, by adhesive or welding. (8) The shoe sole according to any one of claims 2 to 5, wherein the tensile-resistant element is a cloth or mesh made of fibers that are strong against tensile force and have little elongation.