Abstract:
Footwear having a vacuum pump for removing fluid from its interior. The footwear can have a rigid outer shell, a flexible material bonded to the rigid outer shell, a thin sheath within the flexible material, a heelstrike-actuated vacuum pump in the heel, and a vacuum hose connecting the vacuum pump to the interior. The pump can be configured to reduce or increase pressure within the footwear to provide different results.

Description:
[0001]    This application claims priority to U.S. Provisional Patent Application Serial No. 60/422,963, filed on Nov. 1, 2002 and entitled VACUUM-SUSPENDED SHOE, which is herein incorporated by reference in its entirety. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates to an apparatus for suspending footwear, such as a shoe, from the human body by means of vacuum.  
         SUMMARY OF THE INVENTION  
         [0003]    One embodiment of the present invention relates to an apparatus for use on a foot that includes a support portion, a first material within the support portion and enclosing a space in which a foot may be placed, a pump embedded in the heel, and a conduit connecting the pump to the space.  
           [0004]    Another embodiment relates to a method for removing fluid from within footwear. The steps of this embodiment can include providing a first material within the interior of the footwear that forms a space into which a foot can be placed and drawing a vacuum against the space after a user&#39;s foot is inserted into the footwear.  
           [0005]    Another embodiment of the present invention relates to a method for changing the fluid pressure from within footwear. One step could be to provide a first material within the interior of the footwear. Another step could be to provide a fluid conduit that enables fluid to flow at least one of in and out of the interior. Still another step could be to control fluid flow in or out of the interior through the fluid conduit after a user&#39;s foot is inserted into the footwear to change the fluid pressure within the interior.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 is a schematic cross-section of one embodiment of the invention in place on the foot. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0007]    In one embodiment the apparatus  10  comprises a support portion such as an outer portions such as a shoe shell  12 , with a flexible material  14  therein, wherein the material  14  is preferably urethane. The flexible material  14  can be bonded to the shoe shell  12 . The flexible material  14  can cover the entire foot and provide a air seal at, for example, the patient&#39;s ankle A.  
         [0008]    The patient can don a sock  16  or another lining material. Preferably, the sock  16  should not extend above the flexible material  14 . The sock  16  can act as an air wick between foot F and the flexible material  14 . The sock can absorb, hold, or wick away perspiration.  
         [0009]    The apparatus  10  can further include a vacuum pump  18  or other means for reducing pressure. In the preferred embodiment, the vacuum pump  18  is in the heel  20  of the shoe shell  12 . A conduit, such as a hose or tube  22 , connects the vacuum pump  18  to the inside of the flexible material  14 , between the flexible material  14  and the foot F. As the patient walks, the heel-resident vacuum pump  18  is compressed during stance phase and fluid (e.g., air, water vapor, etc.) can be expelled to atmosphere. During the swing phase of walking the heel-resident vacuum pump  18  returns to its normal shape, pulling fluid from between the flexible material  14  and the foot F (and through the sock  16 , if one is used), thus creating a vacuum, i.e., lowered pressure, to hold the foot to the inside of the flexible material  14 .  
         [0010]    The apparatus  10  can further include a one-way valve  24  between the vacuum pump  18  and the hose  22 , and a second one-way valve  26  between the vacuum pump  18  and atmosphere. Any suitable one-way valve may be used for the valves  24 ,  26 , such as a duckbill valve or a ball valve with a seat and spring. The valves  24 ,  26  control the flow of air and substantially stops air from being pumped into the space between the flexible material  14  and the foot F.  
         [0011]    Preferably, the shoe shell  12  is composed of a substantially rigid material that stops the shoe shell from collapsing on the foot as vacuum is drawn.  
         [0012]    The apparatus may have a mid-dorsal opening  30  with a closure means such as Velcro or shoelaces to allow the patient to don the shoe.  
         [0013]    When used to create a lower pressure environment (than ambient) for a foot, the apparatus has application in the removal of moisture (liquid or gas) from the foot or between the foot and shoe. It can also be useful for providing a close fit of a shoe, boot, or the like on the foot, as in downhill ski boots, which could involve the use of conformable shoes, boots, and the like. Still further, the apparatus could also be used to increase or maintain blood flow to the foot, if such flow is desired.  
         [0014]    Or, the apparatus could be reconfigured to increase the pressure upon the foot, i.e., to provide a higher pressure environment (than ambient) for a foot. This could be a way of maintaining or reducing fluid volume in the foot. E.g., forcing air between the material  14  and the foot could prevent pooling of fluid in the foot or even drive fluid out of the foot. Preferably, the material  14  would be substantially incompressible or inelastic such that the increased pressure between the material  14  and the foot would result in at least a certain amount of pressure being applied to the foot rather than resulting entirely in the compression or stretching of the material  14 . Or, the higher pressure environment could be create outside the material  14 , for example, between it and another layer of material  14 .  
         [0015]    The apparatus could be operated such that pressure is changed, for example, periodically. That is, it could be changed back and forth between higher pressure and neutral (or ambient) pressure, higher pressure and lower pressure, neutral pressure and lower pressure, or some combination of higher, lower, and neutral pressures.  
         [0016]    Further, though the apparatus is shown in terms of a shoe configuration, it could also be useful configured as a boot that goes to or above the user&#39;s ankle. This boot could include material  14  such that the pressure chamber created therein either ends where shown in FIG. 1 or extends further up the boot.  
         [0017]    The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive. For example, components or portions of the apparatus  10  described above could, in themselves, be provided separately but still provide some or all of the benefits noted above.