JPS6210641B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to soles for sports shoes such as running shoes, basketball shoes, and soccer shoes.

(Prior Art) It is generally known that athletic shoes such as running shoes have intermediate soles made of elastic foam from the viewpoint of cushioning properties during running.

The weight load that is applied to the sole of the foot during running generally begins when the heel hits the ground on the rear outer side of the heel, and is applied to the heel a, the outer side of the non-stepping area b, the ball of the fifth toe c, and the ball of the first toe. After the part d makes contact with the ground, the first finger part e and the second to fifth finger parts f move sequentially in response to the kicking motion, but Japanese people tend to have a valgus foot compared to Westerners. In many cases, when the ball c of the fifth toe touches the ground, the ball c of the fifth toe begins to touch the ground with the foot largely supinated outward, and the ball c of the fifth toe starts to touch the ball of the first toe. During the ground contact process at part d, the foot rapidly pronates inward and returns to its normal position. In this state, excessive impact pressure is applied to the ball portion d of the first toe in order to maintain the foot in its normal position. This, combined with the rebound elasticity of the midsole, places an excessive load on the knee joint, causing injury to the knee joint and ligaments on the outside of the leg, such as the iliotibial band.

(Object of the Invention) This invention eliminates these drawbacks by imparting shock absorption properties to the portion of the intermediate sole that corresponds to the ball portion of the first finger. , second
This is an object of the present invention to provide an athletic shoe sole that allows smooth kicking of five fingers.

(Structure and Examples of the Invention) This invention will be described below with reference to the drawings.
In this invention, a part of the cushioned intermediate sole 1 corresponding to the ball part d of the first finger is partially hollowed out,
The gist of the invention is a sole of an athletic shoe characterized by having a shock-absorbing foam 2 inserted into the hollowed out part 11.

In this invention, the ball portion d of the first finger is the first finger.
It refers to the area from the head of the metatarsal bone to the bottom of the first proximal phalanx, and is generally referred to as the hallux.

In this invention, the shock-absorbing foam 2
It has viscoelastic properties, and its low impact resilience due to its viscoelasticity converts the impact force into thermal energy, and compared to a perfectly elastic body, it self-absorbs the impact force and has a lower impact resilience. Say what is done.
Specifically, such materials include rubber and EVA.
Foaming and crosslinking by adding a larger amount of adhesive than usual to an elastic material such as the above, and incompletely crosslinked urethane foam are known. In this invention, the hardness of the shock-absorbing foam 2 is 50 according to SRIS-0101 (hardness according to the compression hardness test according to the Japan Rubber Association standard for physical test method of expanded rubber).
Preferably, the angle is between 80° and 80°. If the hardness is less than that, it will be too soft and will easily be compressed and deformed by a small impact, resulting in incomplete shock absorption.If the hardness is higher than that, it will be too hard and the compressive deformation will be small. , shock absorption properties tend to decrease.

In this invention, the hollowed out portion 1 of the cushioned intermediate sole 1 corresponds to the first finger ball portion d.
1 is formed gradually deeper from the inner side 111 to the outer side 112, and correspondingly, the hollowed out part 1
If the foam 2 to be inserted into the foam 2 is made gradually thicker from the inner side 21 to the outer side 22,
Since the shock absorption of the foam 2 can be maximized in the portion corresponding to the outer side of the ball portion d of the first finger, the shock absorption when the ball portion d of the first finger touches the ground is even greater. Become complete. Further, the hollowed out part 11 is hollowed out so that its cross section is half-moon-shaped from the front end side 113 to the rear end side 114. If the cross section from the to the rear end side 24 is formed in a half-moon shape, the shock absorbing property of the foam 2 gradually decreases from the ball part d of the first finger to the first finger part e, and vice versa. The impact resilience can be gradually increased by gradually increasing the thickness of the cushioned intermediate sole 1.
The kicking motion of the finger part e and the second to fifth finger parts f can be performed even more smoothly.

(Actions and Effects of the Invention) Since this invention is configured as described above,
When touching the ground from the ball part c of the fifth finger to the ball part d of the first finger in the running process, even if the foot is greatly supinated when the ball part c of the fifth finger touches the ground,
The ball part c of the finger begins to touch the ground, and during the ground contact process to the ball part d of the first toe, the foot rapidly pronates inward, and the foot returns to its normal position, and the foot touches the ball part d of the first toe. Even if excessive impact pressure is applied, the impact-absorbing foam 2 is inserted into the portion of the intermediate sole 1 that corresponds to the ball portion d of the first finger, so that even if excessive impact pressure is applied, the impact pressure will not be applied to the ball portion d of the first finger. The excessive impact pressure is completely absorbed by the impact-absorbing foam 2. Therefore, when the ball part d of the first toe touches the ground, the foot can be easily held in the normal position, so that excessive stress is not applied to the outer ligaments of the leg such as the knee joint and iliotibial band as in the conventional method. These injuries are avoided without loading. In addition, during the running process, when the ball part d of the first finger touches the ground, the foot is easily held in the normal position.
Following the grounding step of the ball portion d of the first finger, the kicking motion of the first finger e and the second to fifth fingers f can be performed extremely smoothly. In the drawings, numeral 3 indicates the outer sole, and numeral 4 indicates the wet sole.

[Brief explanation of the drawing]

The drawings show embodiments, and FIG. 1 is a sketch of the sole of the sports shoe of the present invention, FIG. 2 is a sketch showing the assembled state of the sole of the sports shoe of FIG. 1, and FIG. FIG. 1 is a sectional view taken along line AA, and FIG. 4 is a plan view of the foot. Explanation of symbols, 1... Middle bottom, 11... Hollowed out part, 111... Inner side, 112... Outer side, 11
3...Tip side, 114...Rear end side, 2...Shock absorbing foam, 21...Inner side, 22...Outer side, 23...Tip side, 24...Rear end side, 3... ...outer sole, 4...wet sole, a...heel of foot, b
...outer side of the non-stepping part of the foot, c...ball part of the fifth toe, d...ball part of the first toe, e...first toe part, f...the first toe of the foot 2-5 fingers.

Claims (1)

[Claims] 1. An athletic shoe sole characterized in that a portion of a cushioned intermediate sole 1 corresponding to the ball portion d of the first toe is partially hollowed out, and a shock-absorbing foam 2 is inserted into the hollowed out portion 11.