Abstract:
Disclosed is a boot shape keeper capable of holding a boot in a fixed shape, removing malodor from the insole of the boot by allowing the insole of the boot to be opened to outside air while the boot is held. The boot shape keeper  1 , which is inserted into a shaft part  21  of a boot to keep a shape of the shaft part  21  of a boot, includes a cylindrical body part  30  made by forming a plastic sheet  10  having a gas pre-encapsulated into a cylindrical shape, and a through hole  42   b  provided at a lower portion of a side wall surface of the body part  30 , or a groove portion formed at a lower end of the side wall of the body part  30 , wherein the body part  30  has a fixed shape provided by the encapsulated gas.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a boot shape keeper for holding boots in a fixed shape. 
         [0003]    2. Description of the Related Art 
         [0004]    With long boots or the like put off and left at a main entrance or the like, the shaft part of the boot bends easily. If the boots are left in this state for a long time, a crease is formed at the bent part of the shaft part, and, further, shape off-set may occur. It is therefore necessary to maintain boots in such a way that the shaft part is not bent when the boots are not used for a long time. 
         [0005]    In the past, in order to prevent such bending at the shaft part of a boot, a boot keeper is proposed (for example, refer to Japanese Patent Application Laid-Open No. 2005-6915 (Patent Document 1)). This boot keeper fits in the shaft part of a boot to hold the shape of the shaft part, and has a crease-smoothing member for smoothing a crease formed near the ankle joint of the shaft part. Further, Japanese Patent Application Laid-Open No. 2002-223813 (Patent Document 2) discloses a technique on a shape holder formed by a transparent plastic bag having an outer shape which can expand inside the shaft part of the boot as air is fed from a compressed air feeding/discharging valve. According to the technique disclosed in Patent Document 2 can expand the bag by filling compressed air therein, so that with the shape holder fitted in the shaft part of the boot, the boot is not bent and stands upright, thus significantly contributing in holding the shape of the boot. 
         [0006]    By the way, the insole part of the boot from the heel to the tiptoe where the leg is to be fitted absorbs the sweat from the sole. If a person keeps walking on the boots, friction is added to raise the temperature in the boots, making the environment where sweat-oriented germs are easy to breed. In order to prevent breeding of such germs, the humidity of the insole part must be discharged. 
         [0007]    However, the boot keeper according to the technique disclosed in Patent Document 1 is configured as a column in which a cloth bag longer than the shaft part is enclosed. When the boot keeper with the above configuration is fitted in the shaft part of the boot, the insole part is sealed from the outside air. Because the technique disclosed in Patent Document 2 is also configured to expand the cloth bag in the shaft part of the boot, the insole part of the boot is likewise sealed from the outside air. 
         [0008]    As a result, humidity in the insole part of the boot cannot be discharged, causing breeding of germs and releasing an offensive odor. 
       SUMMARY OF THE INVENTION 
       [0009]    Accordingly, the present invention has been devised in view of the foregoing problems, and it is an object of the invention to provide a boot shape keeper capable of holding a boot in a fixed shape, removing malodor from the insole part of the boot by allowing the insole part of the boot to be opened to outside air while the boot is held. 
         [0010]    A boot shape keeper according to a first aspect of the invention is a boot shape keeper to be inserted into a shaft part of a boot to keep a shape of the shaft part of a boot, the boot shape keeper comprising a cylindrical body part made by forming a plastic sheet having a gas pre-encapsulated into a cylindrical shape; and a through hole provided at a lower portion of a side wall surface of the body part, or a groove portion formed at a lower end of the side wall of the body part, wherein the body part has a fixed shape provided by the encapsulated gas. 
         [0011]    The boot shape keeper according to a second aspect of the invention is characterized in that at least one small through hole is further formed in a side surface of the body part according to the first aspect of the invention. 
         [0012]    Since the invention with the above-described configuration ensures a fixed shape, the shaft part does not bend but stands still, making it possible to keep the upright shape of the boot keeper. With the boot keeper being formed cylindrical and the presence of the groove portion and through hole, an offensive odor can be removed from the insole part of the boot by making the insole part communicatable with the outside air. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of a boot shape keeper according to a first embodiment to which the invention is applied; 
           [0014]      FIG. 2  is a diagram for explaining air chambers arranged on a plastic sheet; 
           [0015]      FIG. 3  is a diagram showing an example in which the boot shape keeper formed cylindrical is actually fitted in the shaft part of a boot; 
           [0016]      FIG. 4  is a horizontal cross-sectional view of the boot shape keeper; 
           [0017]      FIG. 5  is a perspective view of a boot shape keeper according to a second embodiment to which the invention is applied; 
           [0018]      FIG. 6  is a diagram showing another example of the second embodiment; 
           [0019]      FIG. 7  is a diagram showing an example of a boot shape keeper which reflects the technical ideas of both of the first embodiment and the second embodiment; 
           [0020]      FIG. 8  is a perspective view of a boot shape keeper according to a third embodiment to which the invention is applied; and 
           [0021]      FIG. 9  is a diagram showing an example in which the boot shape keeper according to the third embodiment is actually fitted in the shaft part. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    A boot shape keeper for holding boots in a fixed shape will be explained in detail below as the best mode for carrying out the invention, referring to the accompanying drawings. 
       First Embodiment 
       [0023]      FIG. 1  shows a perspective view of a boot shape keeper  1  according to a first embodiment to which the invention is applied. This boot shape keeper  1  is formed mainly by rolling a plastic sheet  10  into a coupled cylindrical shape. 
         [0024]    The plastic sheet  10  is a thermoplastic resin sheet, such as non-permeable polyethylene. The thermoplastic resin may be adequately selected from polypropylene, polyethylene terephthalate, nylon, vinyl chloride, polycarbonate, etc. in addition to polyethylene. 
         [0025]    The plastic sheet  10  has strip air chambers  11  elongated in an up-down direction y and arranged in columns in a widthwise direction x as shown in  FIG. 2 . A gas is sealed in the air chambers  11  beforehand. The air chambers  11  are formed by placing two rectangular sheets constituting the plastic sheet  10  one on the other and press-bonding the rectangular sheets in the up-down direction, which is not restrictive, and may be realized by any well-known method. In the example of  FIG. 2 , the air chambers  11  are formed at a surface  10   b  of the plastic sheet  10 . That is, the air chamber  11  is formed into a projecting shape on the surface as seen from a cross section. 
         [0026]    After producing such a plastic sheet  10 , the plastic sheet  10  is rolled in the widthwise direction x. At this time, as shown in  FIG. 1 , the plastic sheet  10  is rolled in the widthwise direction x in such a way that a top surface  10   b  of the plastic sheet  10  where the air chambers  11  are formed are rolled in the widthwise direction x. The ends in the widthwise direction x are coupled together to form a cylinder, thereby forming a through hole  13  penetrating in the up-down direction y. 
         [0027]    At this time, the air chambers  11  have not been formed at a rear surface  10   a  of the plastic sheet  10  yet, and the rear surface  10   a  is a smooth surface. Accordingly, the plastic sheet  10  can be easily rolled into a cylinder form so that the rear surface  10   a  becomes outside, and the top surface  10   b  becomes inside. 
         [0028]    At the time of actually using the boot shape keeper  1  formed into a cylindrical shape, the boot shape keeper  1  is fitted in a shaft part  21  of the boot  2  as shown, for example, in  FIG. 3 . As a result, each of the air chambers  11  which constitute the boot shape keeper  1  is pressed between the adjoining air chambers  11 , as shown in the horizontal sectional view in  FIG. 4 . The pressure among these air chambers  11  applies an expansion force f which urges the air chambers  11  outward. Although the outside of the boot shape keeper  1  circumscribes the internal surface of the fitted shaft part  21 , the expansion force f based on the pressure between the air chambers  11  is applied to the shaft part  21 . As a result, since the force to urge the air chambers  11  outward is normally applied to the shaft part  21 , the shaft part  21  of the boot  2  does not bend but stands upright, thus contributing to keeping the shape. Particularly, according to the invention, the boot shape keeper  1  can be fitted without projecting from the shaft part  21 , thus making it possible to give a customer an image of standing upright at the time the boots are displayed as an exhibit. 
         [0029]    The volumes, sizes, positions, pitches, quantity, shapes, etc. of the air chambers  11  are adjusted beforehand so that the desired expansion force f is applied by the pressure among the air chambers  11 . It is desirable that the individual dimensions, such as the sizes and volumes, should be uniform in order to exert stable expansion force f. The air chambers  11  may be formed as mutually-independent spaces, or may be formed as mutually continuous spaces. In case of making the air chambers  11  continuous, a bypass or the like may be provided to interconnect the air chambers  11 . 
         [0030]    As shown in  FIG. 3B , there may be a case where the shaft part  21  of the boot  2  has a streamline shape. When the boot shape keeper  1  is fitted in the shaft part  21  with such a shape, as shown in  FIG. 3B , the gas in the air chambers  11  is distributed into a swelling portion of the shaft part  21  from a recessed portion thereof. Particularly, the air chambers  11  are formed like strips in the up-down direction, so that the gas enclosed in the air chambers  11  easily moves in the up-down direction to be distributable. The provision of the air chambers  11  allows the gas to be distributed along the streamline of the shaft part  21 , exerting the expansion force. As a result, excessive expansion force is not locally applied to the leather that constitutes the shaft part  21 , making it possible to achieve shape maintenance friendly to the leather constituting the shaft part  21 . 
         [0031]    The through hole  13  is formed by rolling the boot shape keeper  1  in the widthwise direction x into a cylindrical shape. As shown in  FIG. 3 , therefore, an insole part  23  as space including the insole of the boot  2  is released to the outside air via the through hole  13 . It is desirable to raise the boot shape keeper  1  to the height which does not reach a heel part  24  at the time of fitting the boot shape keeper  1  in the shaft part  21 . This makes it possible to enhance the openness of the insole part  23  to the outside air. 
         [0032]    This allows the humidity in the insole part  23  of the boot  2  to be discharged to prevent breeding of germs, thus suppressing an offensive odor. 
         [0033]    The foregoing description of the embodiment has been given of the case where the air chambers  11  explained are formed at the top surface  10   b  of the plastic sheet  10 . As the plastic sheet  10  is formed into a cylindrical shape so that the top surfaces  10   b  of the air chambers  11  form the inner wall, it is possible to enhance the degree of pressure between the air chambers  11  which project inward. This makes it possible to exert the expansion force f. 
         [0034]    However, the air chambers  11  should not necessarily be formed at the top surface  10   b  of the plastic sheet  10 . For example, regardless of whether or not the air chambers  11  are formed at the top surface  10   b,  the air chambers  11  may simply be formed in a string. 
       Second Embodiment 
       [0035]      FIG. 5A  shows a perspective view of a boot shape keeper  3  according to a second embodiment to which the invention is applied. This boot shape keeper  3  has a body part  30  formed by rolling a plastic sheet with a gas enclosed therein beforehand into a cylindrical shape, and at least one projecting part  32  projecting downward from the lower end of the body part  30 . A through hole  31  is formed in the cylindrically formed body part  30 . Although the following description will be given of a case where two projecting parts  32  are formed, which is not restrictive, the projecting parts  32  may be formed in any quantity, any volume and any shape. 
         [0036]    The plastic sheet is a thermoplastic resin sheet, such as non-permeable polyethylene. The thermoplastic resin may be adequately selected from polypropylene, polyethylene terephthalate, nylon, vinyl chloride, polycarbonate, etc. in addition to polyethylene. 
         [0037]    The body part  30  can maintain the fixed shape with the air enclosed therein. The projecting part  32  has a gas enclosed therein beforehand, and is configured so as to feed the gas at least between the body part  30  and the projecting part  32  or discharge the gas therefrom. That is, the internal spaces of the projecting parts  32  and the internal space of the body part  30  are connected mutually. 
         [0038]    The projecting part  32  can be elastically contracted up and down. Since the internal spaces of the projecting parts  32  are connected to the internal space of the body part  30 , pressing the projecting part  32  from the bottom causes the projecting parts  32  to elastically contract as shown in  FIG. 5B . As a result, the height of the boot shape keeper  3  can be set low. In the meantime, the gases in the projecting parts  32  are fed into the body part  30 . The projecting parts  32  may be pressed in to be contracted by adjusting the quantity of the gases to be enclosed in the body part  30  and the projecting parts  32 , so that the gas fed into the body part  30  causes to act as the expansion force f. 
         [0039]    According to the invention, particularly, the provision of the projecting parts  32  smaller in volume than the body part  30  can allow the projecting parts  32  to be easily and elastically contracted. 
         [0040]    The body part  30  and the projecting part  32  may be made of an elastic material with a fixed form, such as urethane. As the projecting parts  32  are formed with a smaller area than the body part  30 , the projecting parts  32 , when pressed, can easily and elastically be contracted. 
         [0041]    At the time of actually using the boot shape keeper  3  formed into a cylindrical shape, the boot shape keeper  3  is fitted in the shaft part  21  of the boot  2  as shown, for example, in  FIG. 6A . Since the body part  30  has air enclosed therein to keep a fixed shape, the shaft part  21  does not bend but stands upright, so that the shaft part  21  can hold the upright shape. If the boot  2  like a half boot, etc. has a short shaft part  21 , as shown in  FIG. 6B , the boot shape keeper  3  is fitted in the shaft part  21 , and then pressed downward to contract the projecting parts  32 . This makes it possible to lower the height of the boot shape keeper  3  to match with the length of the shaft part  21 . 
         [0042]    At the time of displaying the boots  2  as an exhibit, therefore, it is also possible to give the image that the boots  2  naturally stand still by making each boot shape keeper  3  not visible from the customer&#39;s field of view. Regardless of whether the boot  2  is a long boot with a long shaft parts  21  or a half boot, etc. with a short shaft part  21 , i.e., regardless of the length of the shaft part of the boot, the height can be adjusted with the boot shape keeper  3  whose projecting parts  32  are configured to be elastically contractable, so that the boot shape keeper  3  cannot be seen from the customer&#39;s field of view. 
         [0043]    The through hole  31  is formed by making the boot shape keeper  3  into a cylindrical shape. As shown in  FIG. 6 , therefore, the insole part  23  as the space including the insole of the boot  2  is released to the outside air via the through hole  13 . This makes it possible to discharge the humidity in the insole part  23  of the boot  2  to prevent breeding of germs, thus suppressing an offensive odor. 
         [0044]      FIGS. 7A and 7B  show a boot shape keeper  7  which reflects the technical ideas of both of the first embodiment and the second embodiment. 
         [0045]    The boot shape keeper  7  has strip air chambers  11  elongated in the up-down direction y and arranged in columns in the widthwise direction x with a gas sealed in the air chambers  11  beforehand. The air chambers  11  are formed by placing two rectangular sheets constituting the plastic sheet  10  one on the other and thermocompression bonding the rectangular sheets in the up-down direction. Some air chambers  11  are elongated by a length corresponding to the projecting part  32 . These air chambers  11  are continual to one another via the bypass (not shown), so that air can be fed to the entire boot via at least one air feeding inlet. 
         [0046]    The plastic sheet  10  with the flat shape is rolled in the widthwise direction x into a cylindrical shape, thus providing the boot shape keeper  7  with such a shape as shown in  FIG. 7B . 
         [0047]    In this boot shape keeper  7 , outward expansion force can be applied by the pressure from the adjacent air chambers  11 . In addition, as the projecting part  32  is provided to be elastically contractable, the height can be adjusted. Further, the expansion force f may be exerted by the gas fed into the body part  30  by contracting the projecting part  32  with pressure. 
       Third Embodiment 
       [0048]      FIGS. 8A and 8B  show perspective views of a boot shape keeper  4  according to a third embodiment to which the invention is applied. This boot shape keeper  4  has a body part  40  formed by rolling a plastic sheet with a gas enclosed therein beforehand into a cylindrical shape, and a through hole  42   b  provided in the lower portion of the side wall of the body part  40 , or a groove portion  42   a  formed in the lower end of the side wall of the body part  40 . The groove portion  42   a  and through hole  42   b  may have any shape or may be formed in any quantity. The through hole  42   b  is connected to the through hole  41  in the cylindrical body part  40 . Although the location at which the through hole  42   b  is formed is adjusted beforehand in connection with at least the position of the insole part  23  of the boot  2 , it is desirable that the through hole  42   b  should be formed at any position at least at the lower half. The body part  40  can maintain the fixed shape with the air enclosed therein. 
         [0049]    At the time of actually using the boot shape keeper  4  formed into a cylindrical shape, the boot shape keeper  4  is fitted in the shaft part  21  of the boot  2  as shown, for example, in  FIGS. 9A and 9B . Since the body part  40  has air enclosed therein to keep a fixed shape, the shaft part  21  does not bend but stands upright, thus significantly contributing to maintaining the upright shape. 
         [0050]    As shown in  FIG. 9A , the insole part  23  as the space including the insole of the boot  2  is released to the outside air via the groove portion  42   a  and the through hole  41 . This makes it possible to discharge the humidity in the insole part  23  of the boot  2  to prevent breeding of germs, thus suppressing an offensive odor. From the viewpoint of easier production, it is desirable that the groove portion  42   a  should have a rectangular shape or a rectangular shape with rounded corners. 
         [0051]    As shown in  FIG. 9B , the insole part  23  as the space including the insole of the boot  2  is released to the outside air via the through hole  42   b  and the through hole  41 . This makes it possible to discharge the humidity in the insole part  23  of the boot  2  to prevent breeding of germs, thus suppressing an offensive odor. 
         [0052]    Of course, at least two groove portions  42   a  may be provided to demonstrate a function similar to that of the projecting parts  32  in the second embodiment. 
         [0053]    Furthermore, according to this embodiment, at least one small through hole may be further formed in the side surface of the body part  40 . Multiple small through holes may be formed in the side surface of the body part  40  which faces the inner wall of the shaft part  21 , thereby improving the permeability and ventilatory. 
         [0054]    According to the third embodiment, of course, the body part  30  may be formed of an elastic material with a fixed shape, such as urethane, in place of a plastic sheet.