Patent Publication Number: US-11033072-B2

Title: Sole structure and shoe including the sole structure

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to Japanese Patent Application No. 2018-176353 filed on Sep. 20, 2018, the entire disclosure of which is incorporated by reference herein. 
     BACKGROUND 
     The present disclosure relates to a sole structure and a shoe including the sole structure. 
     Conventionally, for example, a sole structure descried in Japanese Translation of PCT International Application No. 2008-517699 has been proposed as a sole structure that supports a foot of a person (which will be hereinafter referred to as a “wearer”) who wears shoes. 
     In Japanese Translation of PCT International Application No. 2008-517699, a sole structure including at least one shoe bottom layer including a toe portion, a heel portion, and an intermediate portion is disclosed. The intermediate portion has a plurality of opening portions that have been formed so as to vertically pass therethrough. The intermediate portion is elastically flexible such that, due to the plurality of opening portions, a thickness of the layer does not change and a length of the layer changes in the intermediate portion. Each of the toe portion and the feel portion is relatively displaceable with respect to the intermediate portion in a longitudinal direction (that is, a foot length direction). 
     SUMMARY 
     In the sole structure of Japanese Translation of PCT International Application No. 2008-517699, each of the toe portion and the heel portion is relatively displaceable with respect to the intermediate portion in the foot length direction due to the intermediate portion including the plurality of opening portions. Thus, it is possible to appropriately change the length in the foot length direction in the sole structure in accordance with a size of the foot of the wearer. However, in the above described sole structure, a foreign matter, water, or the like easily enters the sole structure through the plurality of opening portions from a road surface or a ground. As a result, a problem arises in which the wearer cannot safely and comfortably wear shoes having the above described sole structure. 
     In view of the foregoing, the present disclosure has been devised and it is therefore an object of the present disclosure to make it possible to appropriately change a length of a sole structure at least in a foot length direction mainly in accordance with a size of a foot of a wearer while preventing entry of a foreign matter or the like. 
     To achieve the above described object, according to a first aspect of the present disclosure, provided is a sole structure for shoes, including a first sole portion, and a second sole portion arranged behind the first sole portion. The first sole portion includes a first sole body and a first connection portion provided in a rear portion of the first sole body. The second sole portion includes a second sole body and a second connection portion that is provided in a front portion of the second sole body and is connected to the first connection portion so as to overlap the first connection portion in a vertical direction. Each of the first sole portion and the second sole portion is configured such that the first sole body and the second sole body come close to each other and are separated from each other at least in the foot length direction while maintaining a state in which the first connection portion and the second connection portion overlap each other in the vertical direction. 
     In the first aspect, the first sole body and the second sole body come close to each other and are separated from each other at least in the foot length direction, and therefore, a length of the sole structure at least in the foot length direction can be appropriately changed mainly in accordance with a size of a foot of a wearer. Also, the state in which the first connection portion and the second connection portion overlap each other in the vertical direction is maintained, and therefore, in particular, even when the first sole body and the second sole body are separated from each other in the foot length direction, a gap between the first sole body and the second sole body hardly occurs. Therefore, a foreign matter, water, or the like hardly enters the sole structure from the road surface or the ground. Accordingly, in the first aspect, entry of a foreign matter or the like can be prevented and also the length of the sole structure at least in the foot length direction can be appropriately changed mainly in accordance with the size of the foot of the wearer. 
     According to a second aspect, in the first aspect, at least one connection shaft that protrudes in the vertical direction is provided in one of the first connection portion and the second connection portion, and the first connection portion and the second connection portion are connected to each other via the connection shaft so as to overlap each other in the vertical direction and are configured to relatively move with respect to each other at least in the foot length direction. 
     In the second aspect, the first connection portion and the second connection portion are connected to each other via the connection shaft so as to overlap each other in the vertical direction and are configured to relatively move with respect to each other at least in the foot length direction, and therefore, it is easy to achieve a configuration in which the first sole body and the second sole body come close to each other and are separated from each other at least in the foot length direction while maintaining the state in which the first connection portion and the second connection portion overlap each other in the vertical direction. With the above described simple configuration, similar working effects to those of the first aspect can be achieved. 
     According to a third aspect, in the second aspect, only one said connection shaft is provided, and each of the first connection portion and the second connection portion is configured to turn in a foot width direction about the connection shaft as a turning shaft. 
     In the third aspect, each of the first connection portion and the second connection portion is configured to turn in a foot width direction about the connection shaft as a turning shaft, and therefore, one of the first sole body and the second sole body relatively moves with respect to the other one of the first sole body and the second sole body also in the foot width direction. Thus, a relative positional relationship between the first sole body and the second sole body is not limited by a size of foot of wearer and can be adapted to various operations of the foot of the wearer. 
     According to a fourth aspect, in the first aspect, an upper surface of the first sole body, an upper surface of the second sole body, and an upper surface of one of the first connection portion and the second connection portion are formed as a foot sole support surface that supports a sole of a foot of a wearer. The upper surface of one of the first connection portion and the second connection portion is flush with the upper surface of each of the first sole body and the second sole body. 
     In the fourth aspect, the foot sole support surface formed of the upper surface of the first sole body, the upper surface of the second sole body, and the upper surface of one of the first connection portion and the second connection portion can be entirely made smooth. As a result, the wearer does not feel discomfort in the sole of the foot and also the sole of the foot of the wearer can be stably supported. 
     According to a fifth aspect, in the first aspect, the first connection portion is arranged under the second connection portion, and an outsole is stacked on a lower side of the first connection portion. 
     In the fifth aspect, with the outsole stacked on the lower side of the first connection portion, entry of a foreign matter, water, or the like in the sole structure through the first connection portion from the road surface or the ground can be prevented. 
     According to a sixth aspect, in the first aspect, the second connection portion is arranged under the first connection portion, and an outsole is stacked on a lower side of the second connection portion. 
     In the sixth aspect, with the outsole stacked on the lower side of the second connection portion, entry of a foreign matter, water, or the like in the sole structure through the second connection portion from the road surface or the ground can be prevented. 
     According to a seventh aspect, a shoe including the sole structure of the first aspect is provided. 
     In the seventh aspect, a pair of shoes that exhibit similar working effects to those of the first aspect can be achieved. The wearer can safely and comfortably wear the shoes. 
     According to an eighth aspect, in the seventh aspect, the shoe further includes an upper attached to the sole structure. The upper includes an extensible and contractible elastic portion arranged in a position that corresponds to a position in which the first connection portion and the second connection portion overlap each other in the vertical direction, a first fixed portion arranged in front of the first connection portion and firmly fixed to the first sole body, and a second fixed portion arranged behind the second connection portion and firmly fixed to the second sole body. 
     In the eighth aspect, when the wearer wears the shoes, the elastic portion of the upper extends and contracts in accordance with the size of the foot of the wearer and at least one of the first fixed portion and the second fixed portion moves in the foot length direction. Due to this movement, at least one of the first sole body and the second sole body moves in the foot length direction and the first connection portion and the second connection portion relatively move with respect to each other in the foot length direction. As described above, the length of the sole structure at least in the foot length direction can be adapted to change of a shape of the upper. As a result, the entire shoe can be made to fit mainly the size of the foot of the wearer. 
     As described above, according to the present disclosure, entry of a foreign matter or the like can be prevented and also a length of a sole structure at least in the foot length direction can be appropriately changed mainly in accordance with a size of a foot of a wearer. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an overall perspective view of an entire shoe including a sole structure according to an embodiment. 
         FIG. 2  is a side view of the shoe including the sole structure according to the embodiment when viewed from a medial side. 
         FIG. 3  is a plan view of the sole structure according to the embodiment. 
         FIG. 4  is a cross-sectional view taken along the line IV-IV in  FIG. 3 . 
         FIG. 5  is a bottom view of a first sole portion. 
         FIG. 6  a bottom view of a second sole portion. 
         FIG. 7  is a view that corresponds to  FIG. 2  and illustrates a state of the sole structure when the first sole portion and the second sole portion relatively move with respect to each other in the foot length direction. 
         FIG. 8  is a view that corresponds to  FIG. 4  and illustrates a state of the sole structure illustrated in  FIG. 7 . 
         FIG. 9  is a view that corresponds to  FIG. 4  and illustrates a first modified example of the shoe according to the embodiment. 
         FIG. 10  is a view that corresponds to  FIG. 4  and illustrates a second modified example of the shoe according to the embodiment. 
         FIG. 11  is a view that corresponds to  FIG. 4  and illustrates a third modified example of the shoe according to the embodiment. 
         FIG. 12  is a view that corresponds to  FIG. 4  and illustrates a fourth modified example of the shoe according to the embodiment. 
         FIG. 13  is a view that corresponds to  FIG. 4  and illustrates a fifth modified example of the shoe according to the embodiment. 
         FIG. 14  is a view that corresponds to  FIG. 4  and illustrates a sixth modified example of the shoe according to the embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     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. 
       FIGS. 1 to 3  illustrate a sole structure  2  according to an embodiment of the present disclosure and a shoe  1  including the sole structure  2 . A pair of the shoes  1  can be used, for example, as athletic shoes for running and various sports, sneakers for daily use, or rehabilitation shoes. 
     Only right shoe of the pair of shoes  1  is described herein as an example. Since a left shoe is symmetrical to the right shoe, only the right shoe will be described in the following description, and the description of the left shoe will be omitted herein. 
     In the following description, the expressions “upper side” and “lower side” represent the vertical positional relationship between respective portions of the shoe  1 , the expressions “front (fore)” and “rear (hind)” represent the positional relationship between respective portions of the shoe  1  in the foot length direction (a longitudinal direction), and the expressions “medial side” and “lateral side” represent the positional relationship between respective portions of the shoe  1  in a foot width direction of the shoe  1 . 
     As illustrated in  FIGS. 1 to 4 , in this embodiment, the sole structure  2  is divided into two portions in the foot length direction. Specifically, the sole structure  2  includes a first sole portion  10  and a second sole portion  20 . 
     (First Sole Portion) 
     The first sole portion  10  is arranged, for example, so as to correspond to a range from a forefoot to a midfoot of a foot of a person (which will be herein after referred to as a “wearer”) who wears the shoe  1 . 
     The first sole portion  10  includes a first outsole portion  11 . The first outsole portion  11  is made of a hard elastic member having a higher hardness than those of a first sole body  12  and a first connection portion  13 , which will be described later. Specifically, for the first outsole portion  11 , for example, thermoplastic resin, such as ethylene-vinyl acetate copolymer (EVA) or the like, thermosetting resin, such as polyurethane (PU) or the like, or a rubber material, such as butadiene rubber, chloroprene rubber, or the like, is suitable. 
     As illustrated in  FIG. 5 , the first sole portion  10  includes the first sole body  12 . The first sole body  12  is stacked on an upper side of the foot sole support surface  11 . The first sole body  12  is made of a soft elastic material. Specifically, for the first sole body  12 , thermoplastic synthetic resin, such as ethylene-vinyl acetate copolymer (EVA) or the like, foam thereof, thermosetting resin, such as polyurethane (PU) or the like, foam thereof, a rubber material, such as butadiene rubber, chloroprene rubber, or the like, foam thereof, or the like is suitable. 
     An upper surface of the first sole body  12  is formed as a portion of a foot sole support surface that supports a range from the forefoot to the midfoot in the sole of the foot of the wearer. 
     As illustrated in  FIGS. 1 to 5 , the first sole portion  10  includes a first connection portion  13 . The first connection portion  13  is made of the same material as that of the first sole body  12 . The first connection portion  13  is provided in a rear portion of the first sole body  12 . The first connection portion  13  is integrally formed with the first sole body  12 . The first connection portion  13  is arranged under a second connection portion  23 , which will be described later. Similar to the first sole body  12 , the first connection portion  13  is stacked on an upper side of the first outsole portion  11 . 
     The first connection portion  13  is formed so as to have a smaller thickness than that of the first sole body  12 . The first connection portion  13  is formed in a stepped shape with respect to the upper surface of the first sole body  12  in a side view. Specifically, an upper surface of the first connection portion  13  is located below the upper surface of the first sole body  12 . A lower surface of the first connection portion  13  is flush with a lower surface of the first sole body  12 . 
     As illustrated in  FIGS. 4 and 5 , a guide  31  is provided in the first connection portion  13 . The guide  31  movably guides a connecting shaft  34 , which will be described later, in the foot length direction. The guide  31  is formed so as to be recessed in a groove shape upwardly from the lower surface of the first connection portion  13 . The guide  31  is formed so as to be longer in the foot length direction than in the foot width direction. The guide  31  is arranged substantially in a center in the foot width direction in the first connection portion  13 . The guide  31  is covered by the first outsole portion  11  from below such that an inner space is sealed (see  FIG. 4 ). 
     The guide  31  has a through hole  32  that passes through in a vertical direction in a bottom portion of the guide  31 . The through hole  32  is provided such that a shaft portion  34   a  of the connecting shaft  34 , which will be described later, passes through the through hole  32  in the vertical direction. The through hole  32  is arranged substantially in a center in the foot width direction in the guide  31 . The through hole  32  is formed so as to be longer in the foot length direction than in the foot width direction. The through hole  32  is formed such that a width of the through hole  32  in the foot width direction is larger than a diameter of the shaft portion  34   a  of the connecting shaft  34 . The through hole  32  is also formed such that the width of the through hole  32  in the foot width direction is smaller than a diameter of a stopper  34   b  of the connecting shaft  34 , which will be described later. 
     (Second Sole Portion) 
     As illustrated in  FIGS. 1 to 4 , the second sole portion  20  is arranged behind the first sole portion  10 . The second sole portion  20  is arranged, for example, so as to correspond to a range from the midfoot of the foot of the wearer to a hindfoot of the foot. 
     The second sole portion  20  includes a second outsole portion  21 . Similar to the first outsole portion  11 , the second outsole portion  21  is made of a hard elastic member having a high hardness. Note that the second outsole portion  21  may be made of the same material as a material of the first outsole portion  11 . As another option, the second outsole portion  21  may be made of a different material from the material of the first outsole portion  11 . 
     As illustrated in  FIG. 6 , the second sole portion  20  includes a second sole body  22 . Similar to the first sole body  12 , the second sole body  22  is made of a soft elastic material. Note that the second sole body  22  may be made of the same material as a material of the first sole body  12 . As another option, the second sole body  22  is made of a different material from the material of the first sole body  12 . 
     The second sole body  22  is stacked on an upper side of the second outsole portion  21 . The upper side of the second sole body  22  is formed as a portion of the foot sole support surface that supports a range from the midfoot to the hindfoot in the sole of the foot of the wearer. 
     The second sole portion  20  includes the second connection portion  23 . The second connection portion  23  is provided in a front portion of the second sole body  22 . The second connection portion  23  is integrally formed with the second sole body  22 . Note that the second connection portion  23  may be made of the same material as a material of the first connection portion  13 . As another option, the second connection portion  23  is made of a different material from the material of the first connection portion  13 . 
     The second connection portion  23  is formed so as to have a smaller thickness than a thickness of the second sole body  22 . The second connection portion  23  is formed in a stepped shape with respect to the lower surface of the second sole body  22  in a side view. Specifically, a lower surface of the second connection portion  23  is located above the lower surface of the second sole body  22 . An upper surface of the second connection portion  23  is flush with the upper surface of the first sole body  12  and an upper surface of the second sole body  22 . That is, the upper surface of the second connection portion  23  is formed as a portion of the foot sole support surface that supports a portion of the sole of the foot of the wearer. 
     As illustrated in  FIG. 6 , a fixing hole  33  is provided in the second connection portion  23 . The fixing hole  33  is formed upward from the lower surface of the second connection portion  23  so as to be a bottomed hole. The fixing hole  33  is formed so as to have a circular shape in a bottom view. The fixing hole  33  is arranged close to a front edge of the second connection portion  23 . The fixing hole  33  is arranged substantially in a center in the foot width direction in the second connection portion  23 . 
     As illustrated in  FIGS. 2 and 3 , the connecting shaft  34  is provided in the second connection portion  23 . As illustrated in  FIG. 4 , the connecting shaft  34  includes the shaft portion  34   a  and the stopper  34   b.    
     The shaft portion  34   a  is formed so as to have a columnar shape that extends in the vertical direction. In this embodiment, the shaft portion  34   a  is formed to have a cylindrical shape. A lower portion of the shaft portion  34   a  is inserted in the through hole  32  of the first connection portion  13 . An upper portion of the shaft portion  34   a  is firmly fixed in the fixing hole  33  of the second connection portion  23 , for example, with an adhesive. 
     The stopper  34   b  is formed so as to have, for example, a substantially disk shape. The stopper  34   b  is formed so as to have a larger diameter than a diameter of the shaft portion  34   a . The stopper  34   b  is integrally formed with the shaft portion  34   a . The stopper  34   b  is housed in the guide  31  of the first connection portion  13  in a state in which the shaft portion  34   a  is inserted in the through hole  32  of the first connection portion  13 . Also, the upper surface of the stopper  34   b  abuts on the guide  31 . 
     The first connection portion  13  and the second connection portion  23  are connected to each other so as to overlap each other in the vertical direction via the guide  31  and the connecting shaft  34 . Specifically, the first connection portion  13  and the second connection portion  23  are connected to each other such that a state in which the upper surface of the first connection portion  13  and the lower surface of the second connection portion  23  face each other in the vertical direction is established. Each of the first connection portion  13  and the second connection portion  23  is relatively movable in the foot length direction. Furthermore, as illustrated in  FIG. 7 , each of the first connection portion  13  and the second connection portion  23  is configured to turn in the foot width direction about the shaft portion  34   a  of the connecting shaft  34  as a turning shaft (see a virtual line in  FIG. 7 ). 
     Note that the upper surface of the first connection portion  13  and the lower surface of the second connection portion  23  may contact each other. In this contact state, a lubricant oil or the like is preferably applied between the upper surface of the first connection portion  13  and the lower surface of the second connection portion  23 . The lubricant oil can reduce occurrence of excessive friction between the upper surface of the first connection portion  13  and the lower surface of the second connection portion  23 . 
     (Upper) 
     As illustrated in  FIG. 1 , the shoe  1  includes an upper  3  that covers the foot of the wearer. The upper  3  is attached to the sole structure  2 . The upper  3  is made of, for example, a knit fabric, a woven fabric, a nonwoven fabric, a synthetic leather, an artificial leather, a natural leather, or the like. A foot insertion portion  3   a  in which the foot of the wearer is inserted is provided in an upper portion of the upper  3 . As illustrated in  FIG. 2 , the upper  3  includes an extensible and contractible elastic portion  3   b , a first fixed portion  3   c , and a second fixed portion  3   d.    
     In the upper  3 , the elastic portion  3   b  is arranged in a position that corresponds to a position in which the first connection portion  13  and the second connection portion  23  overlap each other in the vertical direction. 
     In the upper  3 , the first fixed portion  3   c  is arranged in front of a position that corresponds to the first connection portion  13 . The first fixed portion  3   c  is firmly fixed to a peripheral portion of the first sole body  12 , for example, with a fastening member, such as a string material or the like, or an adhesive. 
     In the upper  3 , the second fixed portion  3   d  is arranged behind a position that corresponds to the second connection portion  23 . The second fixed portion  3   d  is firmly fixed to a peripheral portion of the second sole body  22 , for example, with a fastening member, such as a string material or the like, or an adhesive. 
     (Respective Operations of Sole Structure and Upper) 
     Next, respective operations of the sole structure  2  and the upper  3  according to this embodiment will be described. 
     As illustrated in  FIG. 4 , in a state in which the first sole body  12  and the second sole body  22  are close to each other in the foot length direction, a substantially entire portion of the first connection portion  13  and a substantially entire portion of the second connection portion  23  overlap each other in the vertical direction. 
     In the state illustrated in  FIG. 4 , for example, in a case in which, when the wearer wears the shoe  1 , the elastic portion  3   b  of the upper  3  extends in accordance with the size of the foot of the wearer and the first fixed portion  3   c  moves toward a front of the shoe  1 , an external force toward the front of the shoe  1  is transferred to the first sole body  12  via the first fixed portion  3   c . Then, due to the external force, the first sole body  12  is separated from the second sole body  22  in the foot length direction and the through hole  32  in the guide  31  slides with respect to the shaft portion  34   a  of the connecting shaft  34  in the foot length direction (see  FIG. 8 ). 
     As another option, in the state illustrated in  FIG. 4 , for example, in a case in which, when the wearer wears the shoe  1 , the elastic portion  3   b  of the upper  3  extends in accordance with the size of the foot of the wearer and the second fixed portion  3   d  moves toward a rear of the shoe  1 , an external force toward the rear of the shoe  1  is transferred to the second sole body  22  via the second fixed portion  3   d . Then, due to the external force, the second sole body  22  is separated from the first sole body  12  in the foot length direction and the shaft portion  34   a  of the connecting shaft  34  slides with respect to the through hole  32  in the guide  31  in the foot length direction (see  FIG. 8 ). 
     As illustrated in  FIG. 8 , in the sole structure  2 , even in a state in which one of the first sole body  12  and the second sole body  22  is separated from the other one of the first sole body  12  and the second sole body  22  in the foot length direction, a rear portion of the first connection portion  13  and a front portion of the second connection portion  23  overlap each other in the vertical direction. As described above, each of the first sole portion  10  and the second sole portion  20  is configured such that the first sole body  12  and the second sole body  22  come closer to each other and are separated from each other at least in the foot length direction while a state in which the first connection portion  13  and the second connection portion  23  overlap each other in the vertical direction is maintained. 
     Working Effects of Embodiments 
     As described above, in the sole structure  2  according to the embodiment, the first sole body  12  and the second sole body  22  are configured so as to come close to each other and be separated from each other at least in the foot length direction. Therefore, a length of the sole structure  2  at least in the foot length direction can be appropriately changed mainly in accordance with the size of the foot of the wearer. A state in which the first connection portion  13  and the second connection portion  23  overlap each other in the vertical direction is maintained, and therefore, in particular, even in a state in which the first sole body  12  and the second sole body  22  are separated from each other in the foot length direction, a gap is hardly generated between the first sole body  12  and the second sole body  22 . Therefore, a foreign matter, water, or the like hardly enters the sole structure  2  from the road surface or the ground. Accordingly, in the sole structure  2  according to the embodiment, at least the length of the sole structure  2  in the foot length direction can be appropriately changed mainly in accordance with the size of the foot of the wearer while the entry of the foreign matter or the like can be prevented. Thus, the wearer can safely and comfortably wear the shoe  1  including the sole structure  2 . 
     Also, the first connection portion  13  and the second connection portion  23  are connected to each other via the connecting shaft  34  so as to overlap each other in the vertical direction and are configured so as to be relatively move with respect to each other at least in the foot length direction. In the above described configuration, it is easy to achieve a configuration in which the first sole body  12  and the second sole body  22  come close to each other and are separated from each other at least in the foot length direction while a state in which the first connection portion  13  and the second connection portion  23  overlap each other in the vertical direction. With the above described simple configuration, similar working effects to the above described working effects can be achieved. 
     Also, only one connecting shaft  34  is provided and each of the first connection portion  13  and the second connection portion  23  is configured to turn in the foot width direction about the connecting shaft  34  as the turning shaft. Therefore, one of the first sole body  12  and the second sole body  22  relatively moves with respect to the other one of the first sole body  12  and the second sole body  22  also in the foot width direction. Thus, a relative positional relationship between the first sole body  12  and the second sole body  22  is not limited by the size of the foot of the wearer and can be adapted to various operations of the foot of the wearer. 
     Also, the upper surface of the first sole body  12 , the upper surface of the second sole body  22 , and the upper surface of the second connection portion  23  are formed as the foot sole support surface that supports the sole of the foot of the wearer and the upper surface of the second connection portion  23  is flush with the upper surface of the first sole body  12  and the upper surface of the second sole body  22 . Therefore, the foot sole support surface formed of the upper surface of the first sole body  12 , the upper surface of the second sole body  22 , and the upper surface of the second connection portion  23  can be entirely made smooth. As a result, the wearer does not feel discomfort in the sole of the foot and the sole of the foot of the wearer can be stably supported. 
     Also, the first connection portion  13  is arranged under the second connection portion  23  and the first outsole portion  11  (an outsole) is stacked on a lower side of the first connection portion  13 . With the first outsole portion  11 , entry of a foreign matter, water, or the like to the sole structure  2  through the first connection portion  13  (in particular, the through hole  32 ) from the road surface or the ground can be prevented. 
     Also, the upper  3  includes the elastic portion  3   b , the first fixed portion  3   c , and the second fixed portion  3   d . Therefore, when the wearer wears the shoe  1 , the elastic portion  3   b  of the upper  3  extends and contracts in accordance with the size of the foot of the wearer and at least one of the first fixed portion  3   c  and the second fixed portion  3   d  moves in the foot length direction. By this movement, at least one of the first sole body  12  and the second sole body  22  is caused to move in the foot length direction and the first connection portion  13  and the second connection portion  23  relatively move with respect to each other in the foot length direction. As described above, the length of the sole structure  2  at least in the foot length direction can be adapted to change of the shape of the upper  3 . As a result, the entire shoe  1  can be made fit mainly the size of the foot of the wearer. 
     First Modified Example of Embodiment 
     In the above described embodiment, a configuration in which the first connection portion  13  is arranged below the second connection portion  23  has been described, but the embodiment is not limited to the configuration. That is, as in a first modified example illustrated in  FIG. 9 , the first connection portion  13  may be arranged above the second connection portion  23 . Furthermore, in the first modified example, similar to the second sole body  22 , the second connection portion  23  may be stacked on an upper side of the second outsole portion  21 . 
     Second Modified Example and Third Modified Example of Embodiment 
     Also, in the above described embodiment, a configuration in which, while the guide  31  is provided in the first connection portion  13 , the connecting shaft  34  is provided in the second connection portion  23  has been descried, but the embodiment is not limited to the configuration. That is, as in a second modified example illustrated in  FIG. 10  and a third modified example illustrated in  FIG. 11 , while the guide  31  may be provided in the second connection portion  23 , the connecting shaft  34  may be provided in the first connection portion  13 . 
     Fourth Modified Example of Embodiment 
     Also, as in a fourth modified example illustrated in  FIG. 12 , a configuration in which the sole structure  2  further includes a first upper layer portion  41  and a second upper layer portion  42  may be employed. The first upper layer portion  41  is arranged on an upper side of the first sole body  12  and is integrally formed with the first sole body  12 . The first upper layer portion  41  is formed such that a rear portion of the first upper layer portion  41  is located over the second connection portion  23 . On the other hand, the second upper layer portion  42  is arranged on an upper side of the second sole body  22  and is integrally formed with the second sole body  22 . An upper surface of the first upper layer portion  41  is flush with an upper surface of the second upper layer portion  42 . 
     As described above, in the sole structure  2  of the fourth modified example, each of the first sole portion  10  and the second sole portion  20  is configured such that, while a state in which the first connection portion  13  and the rear portion of the first upper layer portion  41  overlap the second connection portion  23  in the vertical direction is maintained, the first sole body  12  and the second sole body  22  come close to each other and are separated from each other at least in the foot length direction. That is, in the fourth modified example, as compared to the above described embodiment, a configuration in which the rear portion of the first upper layer portion  41  and the second connection portion  23  overlap each other in the vertical direction is further added. Therefore, in the sole structure  2  of the fourth modified example, an advantageous effect of preventing entry of a foreign matter, water, and the like in the sole structure  2  can be further enhanced. 
     Fifth Modified Example of Embodiment 
     A fifth modified example illustrated in  FIG. 13  is a further modified example in which the first upper layer portion  41  and the second upper layer portion  42  are provided in the sole structure  2  described in the third modified example. That is, in the sole structure  2  of the fifth modified example, each of the first sole portion  10  and the second sole portion  20  is configured such that the first sole body  12  and the second sole body  22  come close to each other and are separated from each other at least in the foot length direction while a state in which the respective front portions of the second connection portion  23  and the second upper layer portion  42  overlap the first connection portion  13  in the vertical direction is maintained. That is, in the fifth modified example, as compared to the above described embodiment, a configuration in which the front portion of the second upper layer portion  42  and the first connection portion  13  overlap each other in the vertical direction is further added. Therefore, even with the sole structure  2  of the fifth modified example, similar to the sole structure  2  of the fourth modified example, the advantageous effect of preventing entry of a foreign matter, water, or the like in the sole structure  2  can be further enhanced. 
     Sixth Modified Example of Embodiment 
     In the above described embodiment, a configuration in which the bottomed fixing hole  33  is formed in the second connection portion  23  and the upper portion of the shaft portion  34   a  is firmly fixed in the fixing hole  33  with an adhesive or the like has been described, but the embodiment is not limited to the configuration. For example, a configuration of a sixth modified example illustrated in  FIG. 14  may be employed. Even with the sixth modified example, the first connection portion  13  and the second connection portion  23  can be connected to each other via the connecting shaft  34 . 
     Specifically, as illustrated in  FIG. 14 , instead of the fixing hole  33  described in the above described embodiment, a hole portion  35  and a hole portion  36  are formed in the second connection portion  23 . The hole portion  35  upwardly passes through from a lower surface of the second connection portion  23 . The hole portion  36  is formed downwardly from an upper surface of the second connection portion  23  so as to be bottomed. The hole portion  36  is formed so as to have a larger inner diameter than an inner diameter of the hole portion  35 . A nut member  37  is buried in the hole portion  36 . 
     Also, male screw threading has been performed on the shaft portion  34   a  of the connecting shaft  34 . The lower portion of the shaft portion  34   a  is inserted through the through hole  32  and the first hole portion  35 . The upper portion of the shaft portion  34   a  is screwed to the nut member  37  buried in the hole portion  36 . With the above described configuration, the first connection portion  13  and the second connection portion  23  can be connected to each other. 
     Note that, even in the first to fifth modified examples, the configuration described in the modified example 6 can be applied. 
     Other Embodiments 
     In the above described embodiment, a configuration in which the sole structure  2  is divided into two in the foot length direction has been described, but the embodiment is not limited to the configuration. That is, the sole structure  2  may be configured so as to be divided at least two in the foot length direction. 
     In the above described embodiment, a configuration in which one guide  31 , one through hole  32 , one fixing hole  33 , and one connecting shaft  34  are provided has been described, but the embodiment is not limited to the configuration. That is, a configuration in which a plurality of guides  31 , a plurality of through holes  32 , a plurality of fixing holes  33 , and a plurality of connecting shafts  34  are provided may be employed. 
     In the above described embodiment, a configuration in which the lower surface of the first sole body  12  and the lower surface of the first connection portion  13  are flush with each other has been described, but the embodiment is not limited to the configuration. That is, the lower surface of the first sole body  12  and the lower surface of the first connection portion  13  may be configured not to be flush with each other. Similar applies to the second modified example and the fourth modified example. Furthermore, in the first modified example, the third modified example, and the fifth modified example, the lower surface of the second sole body  22  and the lower surface of the second connection portion  23  may be configured not to be flush with each other. 
     In the above described embodiment, a configuration in which the shaft portion  34   a  having a cylindrical shape is used has been described, but the embodiment is not limited to the configuration. For example, the shaft portion  34   a  may be formed to have various shapes, such as a triangular column shape, a quadrangular column shape, or the like. Similar applies to the first to fifth modified examples. Note that, as in the above described embodiment, as long as the shaft portion  34   a  is formed to have a columnar shape, it is easy to cause each of the first connection portion  13  and the second connection portion  23  to turn about the shaft portion  34   a  as a turning shaft in the foot width direction. 
     Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above described embodiments and various modifications and changes can be made to those embodiments within the scope of the present disclosure. 
     The present disclosure can be industrially applicable, for example, as a sole structure for athletic shoes for running and various sports, sneakers for daily use, or rehabilitation shoes and shoes using the sole structure.