SHOES
20210298416 · 2021-09-30
Inventors
Cpc classification
A43B7/144
HUMAN NECESSITIES
A43B13/186
HUMAN NECESSITIES
A43B7/143
HUMAN NECESSITIES
International classification
Abstract
A sole of a shoe includes a sole body and a plurality of lower protrusions and a plurality of upper protrusions arranged at least in positions each corresponding to a forefoot in the sole body. The sole body is configured such that hardness of a portion corresponding to a midfoot is higher than hardness of a portion corresponding to the forefoot.
Claims
1. A sole for shoes, comprising: a sole body; a plurality of lower protrusions arranged at least in a position corresponding to a forefoot of a foot of a wearer in the sole body, each protruding downward from the sole body; and a plurality of upper protrusions arranged at least in a position corresponding to the forefoot of the foot of the wearer in the sole body, each protruding upward from the sole body, each overlapping with an associated one of the plurality of lower protrusions to make a pair of upper and lower protrusions with the lower protrusion in a cross-sectional view, wherein the sole body is configured such that a hardness of a portion corresponding to a midfoot of the foot of the wearer is higher than a hardness of a portion corresponding to the forefoot of the foot of the wearer.
2. The sole of claim 1, wherein the sole body is configured such that a value of bending hardness in the portion corresponding to the midfoot of the foot of the wearer is 0.258 Nm/deg or more.
3. The sole of claim 1, wherein an upper surface of the sole body in the position corresponding to the midfoot of the foot of the wearer is formed to be substantially flat.
4. The sole of claim 1, wherein the sole body has an outsole and a midsole arranged on the outsole, and the midsole is configured such that a Young's modulus of a portion corresponding to the midfoot of the foot of the wearer is 0.75 MPa or more.
5. The sole of claim 1, wherein a reinforcement body made of a material having higher hardness than the hardness of the sole body is provided in the position corresponding to the midfoot of the foot of the wearer in the sole body, and the reinforcement body extends from a position corresponding to a Lisfranc joint of the foot of the wearer to a position corresponding to a Chopart joint of the foot of the wearer in a foot length direction in the sole body.
6. A sole for shoes, comprising: a sole body; a plurality of lower protrusions arranged at least in a position corresponding to a forefoot of a foot of a wearer in the sole body, each protruding downward from the sole body; and a plurality of upper protrusions arranged at least in a position corresponding to the forefoot of the foot of the wearer in the sole body, each protruding upward from the sole body, each overlapping with an associated one of the plurality of lower protrusions to make a pair of upper and lower protrusions with the lower protrusion in a cross-sectional view, wherein the sole body is configured such that a thickness of a portion corresponding to a hindfoot of the foot of the wearer is larger than a thickness of a portion corresponding to the forefoot of the foot of the wearer.
7. The sole of claim 6, wherein the sole body is configured such that a difference between the thickness of the portion corresponding to the hindfoot of the foot of the wearer and the thickness of the portion corresponding to the forefoot of the foot of the wearer is 8 mm or more.
8. A shoe comprising: the sole of claim 1.
9. A shoe comprising: the sole of claim 2
10. A shoe comprising: the sole of claim 3.
11. A shoe comprising: the sole of claim 4.
12. A shoe comprising: the sole of claim 5.
13. A shoe comprising: the sole of claim 6.
14. A shoe comprising: the sole of claim 7.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
DETAILED DESCRIPTION
[0049] Embodiments of the present disclosure will now be described in detail with reference to the drawings. The following description of the embodiments are mere examples by nature, and are not intended to limit the scope, application, or uses of the present disclosure.
First Embodiment
[0050]
[0051] The drawings illustrate only a left shoe S as an example. Since a right shoe is symmetrical to the left shoe, only the left shoe will be described in the following description, and the description of the right shoe will be omitted herein.
[0052] In the following description, the expressions “upper side” and “lower side” represent the vertical positional relationship between respective portions of the shoe S, the expressions “front (fore)” and “rear (hind)” represent the positional relationship between respective portions of the shoe S in the foot length direction (a longitudinal direction), and the expressions “inner instep side” and “outer instep side” represent the positional relationship between respective portions of the shoe S in a foot width direction. Herein, a “plantar arch” includes both a plantar arch in an inner instep side of a foot f of the wearer and a plantar arch in an outer instep side of the foot f. Furthermore, a “midfoot M” means a region extending from a position of a Lisfranc joint LF of the foot f of the wearer to a position of a Chopart joint CP of the foot in the foot length direction (see
(Upper)
[0053] As illustrated in
[0054] A foot insertion portion 11 in which the foot f of the wearer is inserted is provided in an upper side of the upper 10. An opening portion 12 communicating with the foot insertion portion 11 and extending in the longitudinal direction is formed in an upper side of the upper 10. An eyelet adornment 13 is provided in the opening portion 12. A tongue-piece portion 15 that puts the opening portion 12 in an open state or a close state is provided in a front edge portion of the opening portion 12.
[0055] The eyelet adornment 13 is made of, for example, an artificial leather. The eyelet adornment 13 is arranged in a position corresponding to an instep part of the foot f of the wearer in the upper 10. The eyelet adornment 13 is firmly fixed to the upper 10 by sewing. In left and right edge portions of the eyelet adornment 1, eyelet holes 14 are formed so as to be spaced apart from one another in the foot length direction 3.
[0056] The upper 10 is provided with a shoe lace 16. The shoe lace 16 can be inserted through the eyelet holes 14 located in the left and right edge portions of the eyelet adornment 13. The upper 10 can be made to fit the instep part of the wearer by fastening both end portions of the shoe lace 16 located in the foot insertion portion 11.
(Sole)
[0057] As illustrated in
[0058] The out sole 3 is made of a hard elastic material with higher hardness than that of the midsole 4. Specifically, as a material of the outsole 3, for example, thermoplastic synthetic resins, such as ethylene-vinyl acetate copolymer (EVA) or the like, thermosetting resins, such as polyurethane (PU) or the like, or rubber materials, such as butadiene rubber, chloroprene rubber, or the like are suitable. Note that the hardness of the outsole 3 is preferably set to, for example, 50 A to 80 A in the Asker A scale.
[0059] As illustrated in
[0060] As illustrated in
[0061] As illustrated in
(Lower Protrusions and Upper Protrusions)
[0062] As illustrated in
[0063] As illustrated in
[0064] As illustrated in
[0065] As illustrated in
(Hardness of Sole Body)
[0066] As a feature structure of this embodiment, the sole body 2 is configured such that hardness of a portion thereof corresponding to a midfoot M of the foot of the wearer is higher than hardness of a portion thereof corresponding to the forefoot F.
[0067] Specifically, the sole body 2 is preferably configured such that a value of bending hardness in the portion corresponding to the midfoot M is 0.258 Nm/deg or more. Note that the above-described hardness value is a numerical value that can be obtained in a case where a bending test is performed on the sole body 2 in which a reinforcement body 9 which will be described later is not provided.
[0068] Herein, to check whether the sole body 2 has the above-described hardness value, for example, the following measurement method (bending test) is suitable. That is, using an unillustrated general-purpose bending test machine (for example, “Shoe Flexer”, a product manufactured by Exeter Research), a pressing sensor of the test machine is fixed to be pressed against the sole body 2 in a position of the sole body 2 corresponding to the midfoot M of the sole body 2 in which the reinforcement body 9 which will be described later is not provided and, in this fixed state, a rear end portion of the sole body 2 is raised by a predetermined angle (for example, 40 deg) from a horizontal position. At this time, the hardness value output from the bending test machine may be 0.258 Nm/deg or more.
[0069] In this embodiment, the upper surface of the midsole 4 in positions corresponding to the midfoot M and a hindfoot H is formed to be substantially flat. That is, in the midsole 4, the upper protrusions 8 are not provided at least in the position corresponding to the midfoot M. Thus, the hardness of a portion of the sole body 2 corresponding to the midfoot M can be relatively increased. It is preferable that a Young's modulus of the portion of the midsole 4 corresponding to the midfoot M is made to be 0.75 MPa or more by forming the upper portion of the midsole 4 in the position corresponding to the midfoot M substantially flat. Note that “substantially flat” as described above expresses not only “completely flat” but also “substantially flat” including “slightly rounded.”
(Reinforcement Body)
[0070] As illustrated in
[0071] Specific examples of the hard elastic material include thermoplastic resins, such as thermoplastic polyurethane (TPU), polyamide elastomer (PAE), ABS resin, or the like, and thermosetting resins, such as epoxy resin, unsaturated polyester resin, or the like. Note that fiber-reinforced plastic (FRP) containing carbon fiber, aramid fiber, glass fiber, or the like as fibers for reinforcement and a thermosetting resin or a thermoplastic resin as a matrix resin may be used.
[0072] The reinforcement body 9 has a substantially trapezoidal shape when viewed from the top. Specifically, an outer shape of the reinforcement body 9 has a substantially trapezoidal shape whose side located in the inner instep side has a larger length than a length of a side located in the outer instep side when viewed from the top. That is, the reinforcement body 9 is configured such that, in an arch portion of the foot of the wearer, the hardness is higher in a position corresponding to the arch portion of the inner instep side than in a position corresponding to the arch portion of the outer instep side.
[0073] As illustrated in
[0074] As illustrated in
Advantages of First Embodiment
[0075] As described above, each of the upper protrusions 8 overlaps with an associated one of the lower protrusions 7 to make a pair of upper and lower protrusions with the lower protrusion 7 in a cross-sectional view. Therefore, a reaction force from the ground acts on the lower protrusions 7 and is transferred from the lower protrusions 7 to the planta of the foot f via the upper protrusions 8. Thus, the wearer can recognize the differences of pressures transferred to various portions of the forefoot F.
[0076] In general, when a sole of a shoe contacts the ground during exercise, in a foot of a wearer, a load trajectory (so-called load path) of weight shift that passes from an outer instep side of a heel to a toe via substantially center portions of a hindfoot and a midfoot in a foot width direction and an inner instep side of a forefoot is generated. In the load path, when bending hardness of a portion of the sole corresponding to the midfoot is relatively low, a phenomenon (that is, “shank breaking”) that the portion of the sole corresponding to the midfoot is broken (bent) tends to occur. When this shank breaking occurs, in a course of the above-described load path, in particular, weight shift that passes from the midfoot to the toe is hindered. Thus, a timing of weight shift toward the forefoot of the foot of the wearer is delayed and a weight of the wearer is less likely to be applied to a portion of the sole corresponding to the forefoot. As a result, in a sole of a shoe of a related technology (for example, Japanese Patent Application No. 2019-63491), pressures from lower protrusions and upper protrusions are hardly transferred to the planta in the forefoot of the wearer appropriately.
[0077] In contrast, the sole body 2 of this embodiment is configured such that the hardness of the portion corresponding to the midfoot M is higher than the hardness of the portion corresponding to the forefoot F. In this configuration, the above-described shank breaking is less likely to occur. As a result, in particular, the timing of weight shift from the midfoot M to the forefoot F is not delayed in the load path and the weight of the wearer tends to be applied to a portion of the sole 1 corresponding to the forefoot F. Thus, pressures from the lower protrusions 7 and the upper protrusions 8 can be easily transferred to the planta of the wearer in the forefoot F. Accordingly, in the sole 1 according to the first embodiment and the shoe S including the sole 1, the physical feeling to the pressures transferred to the forefoot F of the wearer can be relatively increased.
[0078] The sole body 2 is configured such that the value of bending hardness in the portion corresponding to the midfoot M is 0.258 Nm/deg or more. As described above, a lower limit of the bending hardness in the portion of the sole body 2 corresponding to the midfoot M is preset, and thus, the sole body 2 in which shank breaking is not likely to occur can be easily achieved.
[0079] The upper surface of the midsole 4 in the position corresponding to the midfoot M is formed to be substantially flat. That is, the lower protrusions 7 are not provided in the upper surface of the midsole 4 in the position corresponding to the midfoot M. Accordingly, stresses are less likely to concentrate in the upper surface. Thus, the bending hardness of the portion of the sole 1 corresponding to the midfoot M can be made higher than the bending hardness of the portion of the sole 1 corresponding to the forefoot F. As a result, shank breaking can be restrained.
[0080] The midsole 4 is configured such that the Young's modulus of the portion corresponding to the midfoot M is 0.75 MPa or more. In this configuration, the bending hardness of the portion of the sole 1 corresponding to the midfoot M can be ensured at a level at which shank breaking can be restrained. Accordingly, the physical feeling to the pressures transferred to the forefoot F of the wearer can be relatively increased.
[0081] Furthermore, with the reinforcement body 9 provided in the portion of the sole body 2 corresponding to the midfoot M, the hardness of the portion of the sole body 2 corresponding to the midfoot M can be easily made higher than the hardness of the portion of the sole body 2 corresponding to the forefoot F. As a result, shank breaking can be restrained.
First Variation of First Embodiment
[0082] In the first embodiment, an embodiment in which the reinforcement body 9 is provided in the sole body 2 is described, but the present disclosure is not limited to this embodiment. For example, as in a variation illustrated in
[0083] Even in this variation, the value of bending hardness in the portion of the sole body 2 corresponding to the midfoot M may be 0.258 Nm/deg or more. As another option, the upper surface of the midsole 4 in the position corresponding to the midfoot M may be formed to be substantially flat. As still another option, the Young's modulus of the portion of the midsole 4 corresponding to the midfoot M may be 0.75 MPa or more. That is, in the sole body 2, as long as the hardness of the portion corresponding to the midfoot M is made higher than the hardness of the portion corresponding to the forefoot F, similar to the first embodiment, the physical feeling to the pressures transferred to the forefoot F of the wearer can be relatively increased.
Second Embodiment
[0084]
[0085] In this embodiment, a sole body 2 is configured such that a thickness of a portion corresponding to a hindfoot H is larger than a thickness of a portion corresponding to a forefoot F. Specifically, in the sole body 2, a difference between the thickness of the portion corresponding to the hindfoot H and the thickness of the portion corresponding to the forefoot F is preferably set to 8 mm or more. Note that, in the sole body 2 of this embodiment, the reinforcement body 9 described in the first embodiment is not provided.
[0086] Specifically, a heel support portion 20 is provided in a position in the sole body 2 corresponding to the hindfoot H which is described in the first embodiment. The heel support portion 20 is made of, for example, the same material as that of a midsole 4. The heel support portion 20 is formed to have a substantially plate shape in a cross-sectional view. The heel support portion 20 preferably has a thickness of 8 mm. A lower surface of the heel support portion 20 is firmly fixed to an upper surface of the midsole 4, for example, with an adhesive.
[0087] In this embodiment, in the sole body 2, a difference between the thickness of the portion corresponding to the hindfoot H and the thickness of the portion corresponding to the forefoot F is made, and thus, a foot f of a wearer can easily tilt forward. As a result, in a load path, a timing of weight shift from the hindfoot H to the forefoot F is not delayed and a weight of the wearer tends to be applied to a portion of the sole 1 corresponding to the forefoot F. Thus, pressures from the lower protrusions 7 and the upper protrusions 8 can be easily transferred to the planta of the wearer in the forefoot F, as appropriate. Accordingly, even in this embodiment, the physical feeling to the pressures transferred to the forefoot F of the wearer can be relatively increased.
[0088] The sole body 2 is configured such that the difference between the thickness of the portion corresponding to the hindfoot H and the thickness of the portion corresponding to the forefoot F is 8 mm or more. With this configuration, the foot f of the wearer can be easily maintained in a tilt forward state. As a result, the physical feeling to the pressures transferred to the forefoot F of the wearer can be relatively increased.
Other Embodiments
[0089] In each of the above-described embodiments, the sole 1 includes the sole body 2 formed of the outsole 3 and the midsole 4, but the present disclosure is not limited thereto. For example, the sole body 2 may be formed of the outsole 3.
[0090] In each of the above-described embodiments, the upper protrusions 8 are arranged only in the position of the midsole 4 corresponding to the forefoot F, but the present disclosure is not limited thereto. For example, in the first embodiment and the variation thereof, the upper protrusions 8 may be arranged in both the position of the sole body 2 corresponding to the forefoot F and the position of the sole body 2 corresponding to the hindfoot H. In contrast, in the second embodiment, the upper protrusions 8 may be arranged in the position of the sole body 2 corresponding to the forefoot F and the position of the sole body 2 corresponding to the midfoot M and/or the hindfoot H.
[0091] In each of the above-described embodiments, the lower protrusions 7 are arranged substantially in the entire portion of the lower surface of the outsole 3, but the present disclosure is not limited thereto. That is, each of the upper protrusions 8 may overlap with an associated one of the lower protrusions 7 to make a pair of upper and lower protrusions with the lower protrusion 7 in a cross-sectional view, and the lower protrusions 7 may not be arranged substantially in the entire portion of the lower surface of the outsole 3.
[0092] In each of the above-described embodiments, the lower protrusions 7 are formed to have different thicknesses and different lengths from one another, but the present disclosure is not limited thereto. That is, the lower protrusions 7 may be formed to have the same thickness and the same length. Similar applies to the upper protrusions 8.
[0093] In the first embodiment and the variation thereof, the upper surface of the sole body 2 in the position corresponding to the midfoot M is formed to be substantially flat, but the present disclosure is not limited thereto. That is, when the value of bending hardness in the portion of the sole body 2 corresponding to the midfoot M is 0.258 Nm/deg or more, the upper surface of the sole body 2 in the position corresponding to the midfoot M may not be formed to be substantially flat.
[0094] In the first embodiment, the reinforcement body 9 has a substantially trapezoidal shape when viewed from the top, but the present disclosure is not limited thereto. That is, the reinforcement body 9 may have various shapes, such as a circular shape, a triangular shape, a pentagonal shape, or the like when viewed from the top.
[0095] In the first embodiment, the reinforcement body 9 is provided between the outsole 3 and the midsole 4 in a stacked arrangement, but the present disclosure is not limited thereto. For example, the reinforcement body 9 may be embedded in the outsole 3 or in the midsole 4. As another option, the upper surface of the reinforcement body 9 may be stacked on the lower surface of the outsole 3. As still another option, the lower surface of the reinforcement body 9 may be stacked on the upper surface of the midsole 4.
[0096] In the second embodiment, the reinforcement body 9 described in the first embodiment is not provided in the sole body 2, but the present disclosure is not limited thereto. That is, even in the second embodiment, the reinforcement body 9 can be provided in the sole body 2.
[0097] In the second embodiment, the heel support portion 20 formed as one member is provided in the position in the sole body 2 corresponding to the hindfoot H, but the present disclosure is not limited thereto. For example, a member (not illustrated) in which the heel support portion 20 is integrally formed with the sole body 2 may be used. That is, in the second embodiment, as long as a difference between the thickness of the portion corresponding to the hindfoot H and the thickness of the portion corresponding to the forefoot F is made in the sole body 2, whether the heel support portion 20 is formed as a separate member from the sole body 2 does not matter.
[0098] Embodiments of the present disclosure have been described above, the present disclosure is not limited to the embodiments described above, and various changes and modifications may be made without departing from the scope of the present disclosure.
Examples
[0099] Examples of a sole according to the second embodiment described above and a shoe including the sole will be described below. Specifically, a test subject wore four shoe test bodies and the test subject's foot pressure when the test subject wore each of the four shoe test bodies was measured. A load ratio of a portion of the sole corresponding to a forefoot (which will be hereinafter referred to merely as a “load ratio”) was calculated from results of the measurement, and then, calculated load ratios were compared and examined. Note that the present disclosure it not limited to the examples.
[Test Bodies and Measurement Conditions]
[0100] In Table 1 blow, major configurations of respective soles applied to the four shoe test bodies used in the measurement and a difference between a thickness of a portion of each of the soles corresponding to the forefoot and a thickness of a portion of the each of the soles corresponding to the hindfoot are illustrated. In Table 1 below, all conditions under which the measurement was performed are illustrated. Note that a member corresponding to the reinforcement body described in the first embodiment is not provided in the soles of the test bodies indicated in Table 1.
TABLE-US-00001 TABLE 1 Difference between Major Configurations of Soles Thicknesses of Portions Heel Support Corresponding to Load Ratio X Test Body (Shoes) Sole Body Portion Forefoot and Hindfoot (%) No. 1 Sample (1) None 4 mm 44.3% (Comparative Example) No. 2 Sample (1) Sample (2) 6 mm 44.5% (Comparative Example) (Thickness: 2 mm) No. 3 Sample (1) Sample (3) 8 mm 50.8% (Example) (Thickness: 4 mm) No. 4 Sample (1) Sample (4) 10 mm 54.1% (Example) (Thickness: 6 mm)
TABLE-US-00002 TABLE 2 Condition Items Contents Test Subject One Adult Mail (Height: 177.6 cm, Weight: 65.4 kg) Posture of Test Subject Static Standing Posture during Measurement Measurement Position Left Foot of Test Subject Used Device X4 Foot & Gait (Name of Manufacturer: XSENSOR) Measurement Time 5 seconds Sampling Frequency 100 Hz
[Method for Calculating Load Ratio]
[0101] Next, a method for calculating the load ratio will be described below.
[0102] First, based on foot pressure data obtained by the foot pressure measurement, a position (which will be hereinafter referred to as a “toe position”) in which a toe (a forefoot front end) of a foot of the test subject contacted a sole of each test body and a position (which will be hereinafter referred to as a “heel position”) in which a heel (a hindfoot rear end) of the foot of the test subject contacted the sole of the test body are specified. Thus, a distance (which will be hereinafter referred to as a “foot length distance”) in a foot length direction in the foot of the test subject contacting the sole of each test body is specified. Then, assuming that the foot length distance is 100%, a position separated from the heel position in a forward direction by a distance of 55.8% of the foot length distance is defined as a position of the forefoot rear end in the foot of the test subject. Thus, a region (which will be hereinafter referred to as a “forefoot region”) of the forefoot in the foot of the test subject contacting the sole of each test body is specified.
[0103] Second, a first total value A for the foot pressure applied to the forefoot region and a second total value B for the foot pressure applied to a region ranging from the toe position to the heel position are calculated. Then, a load ratio X (%) for the foot pressure applied to the forefoot region is calculated according to an expression X=(A/B)×100. Note that an average value obtained when the above-described measurement continued for five seconds is set as a representative value of the load ratio X (%) in the sole of each test body.
[Comparison and Examination]
[0104] The load ratio X (%) of each test body obtained by the above-described measurement is illustrated in Table 1 (see the right column in Table 1) and
[0105] According to the comparison and examination, it was found that the foot pressure on the forefoot region of the sole can be made relatively high by configuring the sole body such that the difference between the thickness of the portion corresponding to the hindfoot and the thickness of the portion corresponding to the forefoot in the sole is 8 mm or more. Thus, it was found that, in the shoes (the test bodies No. 3 and No. 4) of the examples, the foot of the test subject (wearer) can be easily maintained in a tilt forward state and the physical feeling to the pressure on the forefoot of the wearer can be relatively increased.
[0106] The present disclosure is industrially applicable to, for example, soles applied to sport shoes used in various kinds of sports such as running and ball games, sneakers for daily use, and shoes for rehabilitation, and shoes using the soles.