JP3258625B2 - Midsole and insole - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shoe sole, particularly to a midsole and an insole.

[0002]

2. Description of the Related Art A midsole is arranged on an outer sole (ground bottom) to absorb a shock at the time of landing. Therefore, for the midsole, for example, a material having excellent impact buffering properties and rebound resilience, such as EVA (ethylene-vinyl acetate copolymer) sponge (EVA foam), is used. In order to obtain the characteristics of the EVA, the hardness of the EVA sponge is generally set to a relatively small value of 40 ° to 60 °. Therefore, there is a problem that the increase of the pronation is promoted.

In view of the above, there has been conventionally known an invention in which a high hardness pronation suppressing member made of sponge rubber or the like is provided on the inner edge of the heel of the midsole (for example, Japanese Patent Publication No. 61-7801). According to this prior art, pronation can be suppressed.

[0004]

However, in this prior art, pronation can be suppressed at the start of traveling,
There was a problem that the pronation gradually increased during running. Such a problem occurs not only in the midsole but also in the insole.

[0005] The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to prevent pronation which increases during traveling.

[0006]

Prior to describing the configuration of the present invention for achieving the above object, the principle of the present invention will be described. Various studies have shown that pronation gradually increases during running. This is considered to be because the height of the arch portion A of the foot in FIG. 2 gradually decreases during running due to the fatigue of the body such as the leg, and therefore the pronation increases. On the other hand, the temperature of the shoes increases during running. The inventor of the present invention has found that the hardness of the foam of the midsole decreases as the temperature rises.
As described above, the present inventors have discovered that the degree of decrease in hardness, that is, the temperature dependence of hardness differs depending on the material, and completed the present invention.

[0007]

That is, the first aspect of the present invention relates to a midsole shown in FIG.
Is provided with a pronation suppressing member 2 having a lower temperature dependency on hardness than the midsole body 1. The pronation suppressing member 2 and the midsole body 1 are connected at 5 ° C. to 2
Temperature T at which hardness is the same in a temperature range of 5 ° C.
And the hardness of the pronation suppressing member 2 is set to be higher than the hardness of the midsole body 1 when the temperature rises above the temperature T ° C.

When training or the like is performed by wearing shoes having the midsole of the present invention, when the running is started at a low temperature (5 ° C. to 25 ° C.), the midsole body 1 and the pronation suppressing member 2 have the same hardness. Therefore, there is no fear that the inner part 3 will feel uncomfortable. On the other hand, after the start of running, the temperature of the shoe starts to rise, but the pronation suppressing member 2 that hardly decreases in hardness is provided in the inner step portion 3, so that FIG.
Can be prevented from decreasing the height of the arch portion A, so that an increase in pronation during running can be suppressed.

In the first aspect of the present invention, the "inner step portion" means a portion inside the foot (inside the step portion) in the range from the metatarsal bone B1 to the cubic bone B2 in FIG. Also,
"Hardness" refers to a value measured by a JISC type hardness meter,
"Temperature dependence on hardness" refers to the degree of change in hardness with respect to temperature change.

In the first aspect of the present invention, the material constituting the "midsole body 1" of FIG. 1 is most preferably an EVA foam, but a foam using EVA as a main polymer, an RB in addition to the EVA, For example, a foamed resin such as a resin can be used. On the other hand, as the pronation suppressing member 2,
Natural rubber, which is a member with lower temperature dependence than EVA,
Foams or non-foams of diene rubbers such as SBR (styrene butadiene rubber), BR (butadiene rubber), neoprene rubber, urethane rubber, etc., alone or blended, or those rubbers blended with resins such as EVA and RB Although a foam can be used, it is generally preferable to use a foam or a non-foam using rubber such as diene rubber as a main polymer. In addition,
In the present specification, the “main polymer” refers to the polymer having the largest weight among the contained polymers.

In the first invention, the midsole body 1
The pronation suppressing member 2 needs to have a temperature T ° C. at which the hardness is the same in a temperature range of 5 ° C. to 25 ° C. as shown in an example in the graph of FIG. The reason is that if the hardness of the midsole main body 1 and the pronation suppressing member 2 are not substantially the same at the start of running, the inner step 3 will feel uncomfortable. The setting of T ° C. depends on the region and the season, but it is generally preferable to set the temperature after mounting and immediately before the start of running (immediately after warming up). For example, in the autumn climate of Japan (climate suitable for sports), it is preferable to set T ° C to an arbitrary temperature of 10 ° C to 25 ° C, and 15 ° C to 25 ° C.
It is more preferable to set the temperature to an arbitrary value.

The hardness of the midsole body 1 and the pronation suppressing member 2 at 23 ° C. (JIS standard hardness) is preferably set to 40 ° to 65 °.

On the other hand, according to the second aspect of the present invention, at least the inner step 3 of the insole shown in FIG.
Is provided. The pronation suppressing member 2 and the cushion body 1A have a temperature T ° C at which the hardness is the same in a temperature range of 5 ° C to 35 ° C, and when the temperature rises above the temperature T ° C, Suppression member 2
Is set to be higher than the hardness of the cushion body 1A.

When training or the like is performed by wearing shoes having the insole according to the second aspect of the present invention, at the start of running at a low temperature (5 ° C. to 35 ° C.), the cushion body 1A and the pronation suppressing member 2 are substantially the same. Because of the hardness, there is no fear that the inner part 3 will feel uncomfortable. On the other hand, after the start of running, the temperature of the shoe starts to rise, but since the pronation suppressing member 2 that does not easily decrease in hardness is provided in the inner step portion 3, the height of the arch portion A in FIG. Can be prevented, so that an increase in pronation during running can be suppressed.

In the second aspect of the present invention, the "inner step portion" means a portion inside the foot (inside the step portion) in the range from the metatarsal bone B1 to the cubic bone B2 in FIG.

In the second aspect of the present invention, the "pronation suppressing member 2 and the cushion main body 1A" refer to FIG.
(C) A portion of the insole except the surface fabric member 4 having a water absorbing property, such as a woven fabric, a nonwoven fabric, a knitted fabric, a woven fabric, or artificial leather. In FIG. 6A, the surface cloth member 4 is omitted for convenience of drawing.

The term "hardness" refers to a value measured by a JISC type hardness meter, and the term "temperature dependence on hardness" refers to
The degree of change in hardness with respect to temperature change. Also,
As the “hardness of the pronation suppressing member 2 and the cushion member 1A”, the hardness is measured from the back surface 5 of the insole because the surface cloth member 4 affects the measured value of the hardness. In general, since the insole is thin, a plurality of insoles are stacked and the hardness is measured from the back surface 5.

In the second aspect of the present invention, the member constituting the "cushion body 1A" of FIG. 6 is most preferably an EVA foam, but a foam using EVA as a main polymer, RB or the like in addition to the EVA. Can be employed. On the other hand, as the pronation suppressing member 2,
Natural rubber, which is a member with lower temperature dependence than EVA,
Foams or non-foams of diene rubbers such as SBR (styrene butadiene rubber), BR (butadiene rubber), neoprene rubber, urethane rubber, etc., alone or blended, or those rubbers blended with resins such as EVA and RB Although a foam can be used, it is generally preferable to use a foam or a non-foam using rubber such as diene rubber as a main polymer.

In the second invention, the cushion body 1A
The pronation suppressing member 2 needs to have a temperature T ° C. at which the hardness is the same in a temperature range of 5 ° C. to 35 ° C., as shown in an example in the graph of FIG. The reason is that if the hardness of the cushion body 1A and that of the pronation suppressing member 2 are not substantially the same at the time of starting traveling, the inner step 3 will feel uncomfortable. The setting of T ° C. depends on the region and the season, but it is generally preferable to set the temperature after mounting and immediately before the start of running (immediately after warming up). For example, in the autumn climate of Japan (climate suitable for sports), it is preferable to set T ° C to an arbitrary temperature of 20 ° C to 35 ° C, and 25 ° C to 35 ° C.
It is more preferable to set the temperature to an arbitrary value. The reason why the temperature of the insole is higher than that of the midsole is that the temperature of the insole rises immediately after mounting.

The hardness of the cushion body 1A and the pronation suppressing member 2 at 23 ° C. (JIS standard hardness) is preferably set to about 35 ° to 45 °.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 (a) and 1 (b), the midsole body 1 and the pronation suppressing member 2 may be joined by abutment.
As shown in (d), the layers may be stacked in the thickness direction at the inner step portion. In FIGS. 1, 4 and 5, the portion of the pronation suppressing member 2 is shaded.

Further, it is not necessary to provide the pronation suppressing member 2 on the whole of the inner step portion 3, and FIGS. 4 (a) to 4 (c)
As shown in FIG. 2, the inner sole portion 3 may be provided on a part of the inner sole portion 3. For example, an island-shaped portion 10 made of the same material as the midsole body 1 is provided in the pronation suppressing member 2 of the inner foot portion 3. Is also good. That is, the island portion 10 surrounded by the pronation suppressing member 2 may be provided in the portion 3 without stepping on the inner side. On the other hand, FIG.
As shown in (a) to (c), the EVA is also applied to the inner step portion 3.
And the pronation suppressing member 2 may be provided in an island shape on the inner step portion 3.

In the present invention, the pronation suppressing member 2 may be provided mainly on the inner step portion 3, and the pronation suppressing member 2 may be added to a portion other than the inner step portion 3, for example, the rear portion of the heel. . In addition, the midsole body 1
And the pronation suppressing member 2 may be bonded,
The heat press molding may be performed integrally.

The same structure as that of the midsole can be adopted for the insole shown in FIG.

[0025]

Next, in order to clarify the effects of the present invention,
Examples and comparative examples are shown. Example: As shown in FIGS. 1 (a) and 1 (b), a pronation suppressing member 2 made of a foam of diene rubber is provided on an inner step portion 3 and a midsole having other portions as EVA is provided. Marathon shoes were prepared. Comparative Example: A marathon shoe having a midsole made of ordinary EVA was prepared. The shoes of the example and the comparative example were worn on one subject, and the temperature of the midsole of the inner foot portion after warming-up was measured. After running for 20 minutes, the temperature of the midsole of the inner step was measured.
° C. The height of the arch portion A during the ground contact gradually decreased during running, but the shoe of the example had a smaller degree of decrease in the height of the arch portion A. Thereby, the effect of the present invention capable of suppressing the increase of the pronation was confirmed.

[0026]

As described above, according to the first aspect of the present invention, the pronation suppressing member having a small temperature dependency, that is, a member whose hardness is unlikely to be reduced even when the temperature is raised, is provided on the inner step portion of the mid sole. , The suppression of the lowering of the arch portion during running can suppress the increase of the pronation, and the temperature T ° C at which the hardness of the midsole body and the pronation suppressing member becomes the same is 5 ° C to 25 ° C. Since the temperature is set in the temperature range of ° C., there is no fear that the inner step portion will feel uncomfortable at the time of warming up before traveling or immediately after starting traveling.

According to the second aspect of the present invention, since the pronation suppressing member having a small temperature dependency, that is, a member whose hardness is unlikely to decrease even when the temperature is raised, is provided in the inner step of the insole, A temperature T ° C. at which the hardness of the cushion body and the hardness of the pronation suppressing member are equal to each other can be suppressed by suppressing the lowering of the middle arch portion, thereby suppressing the increase of the pronation.
Is set in the temperature range of 5 ° C. to 35 ° C., so that there is no fear that the inner step portion feels uncomfortable at the time of warming up before running or immediately after starting running.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view and a sectional view taken along line AA ′ showing a first embodiment of a midsole of the present invention.

FIG. 2 is a schematic side view showing a structure of a foot bone.

FIG. 3 is a graph showing the temperature dependence of a member.

FIG. 4 is a perspective view and a plan view showing a second embodiment.

FIG. 5 is a plan view showing a third embodiment.

FIG. 6 is a perspective view, a plan view, and a cross-sectional view taken along line CC of an insole showing a fourth embodiment.

[Explanation of symbols]

 1: Midsole body 1A: Cushion body 2: Pronation restraint member 3: Inner step

Continuation of the front page (72) Inventor Osamu Murakami 7-1-1, Minatojima-Nakamachi, Chuo-ku, Kobe Asics Co., Ltd. (56) References JP-A-59-2 (JP, A) JP-A-5-329005 ( JP, A) JP-A-63-294803 (JP, A) JP-A-62-75703 (JP, U) JP-A-60-128506 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , (DB name) A43B 1/00-23/30

Claims (6)

(57) [Claims] At least a part of or the entire inner foot portion of a midsole is provided with a pronation suppressing member having a lower temperature dependency with respect to hardness than the midsole main body. 5 ℃
In the temperature range of ２５25 ° C., the hardness has the same temperature T ° C., and when the temperature rises above the temperature T ° C., the hardness of the pronation suppressing member is larger than the hardness of the midsole body. Midsole set to be. 2. A foam according to claim 1, wherein said midsole body is formed of a foam having ethylene-vinyl acetate copolymer as a main polymer, and said pronation suppressing member is foam or non-foam having rubber as a main polymer. Midsole made of body. 3. The midsole according to claim 1, wherein the hardness of the midsole body and the pronation suppressing member at 23 ° C. is set to 40 ° to 65 °. 4. A pronation suppressing member having a lower temperature dependency with respect to hardness than the cushion body is provided on at least a part or the whole of the inner step portion of the insole, and the pronation suppressing member and the cushion body are 5 ° C. It has a temperature T ° C at which the hardness is the same in a temperature range of up to 35 ° C, and when the temperature rises above the temperature T ° C, the hardness of the pronation suppressing member becomes larger than the hardness of the cushion body. Insole that is set to be. 5. The foam according to claim 4, wherein the cushion body is formed of a foam having an ethylene-vinyl acetate copolymer as a main polymer, and the pronation suppressing member is a foam or a non-foam having rubber as a main polymer. An insole consisting of: 6. The insole according to claim 4, wherein the hardness at 23 ° C. of the cushion body and the pronation suppressing member is set to 35 ° to 45 °.