Abstract:
A pneumatic inflation device disposed within the sole of a shoe and comprising a pump which is entirely within the sole, a pump actuator which is entirely within the sole when not in use, and an inflatable bladder which is entirely within the sole and is operatively connected to the pump. Such a device can include a mechanism to lock the pump actuator within the sole such that the mechanism&#39;s cap is flush with the outer wall of the sole and finger-operable to allow the shoe-wearer to easily operate the inflation device.

Description:
RELATED APPLICATIONS  
       [0001]    This application is a continuation-in-part of co-pending U.S. patent application Ser. No. 09/424,938 filed Feb. 3, 1999, now U.S. Pat. No. 6,305,102, which claims priority from International Application No. PCT/US98/11307 filed Jun. 3, 1998, which in turn claims priority based on U.S. Provisional Patent Application Ser. No. 60/048,689 filed Jun. 3, 1997 now abandoned. The content of such applications is hereby incorporated herein by reference. 
     
    
     
       BACKGROUND OF INVENTION  
         [0002]    This invention is related generally to shoes and, more particularly, to pneumatic cushioning therein.  
           [0003]    1. Field of the Invention  
           [0004]    Prior art shoes have involved a variety of inflation devices disposed at different locations. For instance, previous shoe arrangements have included soles that can be inflated at the arch to provide support. Other shoes contain soles which have sealed inflated chambers disposed within the soles in order to increase vertical bounce. These previous chambers are soft-sided bladders which distort into a more convex or spherical shape upon inflation. If the walls of the bladder are not constrained, for instance, by the structure of the sole of the shoe, the distortion occurs in every direction.  
           [0005]    Others have addressed this problem by placing a foam core inside the bladder and adhering the entire surface of the interior bladder walls to the entire exterior surface of the foam core as is taught in U.S. Pat. No. 5,235,715 to Donzis. This arrangement of adhering all of the surface of the foam core limits the shape of the bladder to the shape of the foam core and does not allow for differential distortions of the bladder as the bladder is inflated. Such prior art shoes also have not allowed for selective adjustment of the pressure in the bladder chambers and may result in uneven air distribution in the sole of the shoe.  
           [0006]    Pumps in prior art shoes have typically been either externally connectable to the shoe&#39;s air chambers or positioned in low stress areas on the upper portion of the shoe such as in the tongue or on the back of the heel. Such prior art shoes encounter different problems in use. For externally connectable pumps, the pump must be retrieved whenever inflation is desired. Pumps positioned on the upper portion add bulk to the shoe and limit agility. Such pumps also inhibit aesthetic choices in shoe design. Aesthetics may be particularly vital for golf shoes or non-athletic shoes.  
           [0007]    In addition, the typical prior art shoe arrangements have either utilized pump actuators which were nonintegral with the shoe and required connection before inflation and disconnection before normal shoe use, or pump actuators which were connected to the external surface of the shoe, such as on the heel as in U.S. Pat. No. 5,222,312 to Doyle. Nonintegral pump actuators require that the shoe wearer retrieve the actuator every time inflation is needed. External pump actuators impose aesthetic limitations on footwear and add bulk to the “footprint” of the footwear.  
           [0008]    Prior art shoes which have incorporated adjustable pneumatic cushioning have typically provided several air chambers in different areas of the sole which are interconnected via tubing. Eliminating the use of several distinct chambers would further reduce the weight of the shoe and simplify shoe construction. In addition, a complementary configuration between the pump, pump actuator and the air chamber or bladder could significantly reduce the bulk of the shoe.  
           [0009]    It is, therefore, desirable to provide for improved pneumatic cushioning in footwear while including all necessary components for such cushioning within shoe and minimizing shoe bulk and aesthetic limitations. A shoe sole which addresses the problems of known footwear would be an important advance in the art.  
         OBJECTS OF THE INVENTION  
         [0010]    It is an object of the invention to provide an improved pneumatic cushioning system entirely within the confines of a shoe sole.  
           [0011]    Another object of the invention is to provide a pneumatic inflation device which is fully recessed in a shoe sole.  
           [0012]    Another object of the invention is to provide a pneumatic inflation device with a locking mechanism to secure the pump actuator entirely within the sole and flush with the sole&#39;s outer wall when not in use.  
           [0013]    Another object of the invention is to provide a locking mechanism which is easily finger-operated to facilitate inflation by a shoe wearer.  
           [0014]    Another object of the invention is to provide a recess for storing the pump actuator to prevent damage thereto.  
           [0015]    Another object of the invention is to provide a pneumatic inflation device in which the bladder and pump are complementary configured so as to minimize shoe bulk.  
           [0016]    Still another object of the invention is to provide a pneumatic inflation device entirely within a shoe sole, in which the pump is positioned to avoid excessive stress.  
           [0017]    Still another object of the invention is to provide a pneumatic inflation device entirely within a shoe sole, which includes a pressure-release valve to permit adjustment of bladder pressure.  
           [0018]    These and other objects of the invention will be apparent from the following descriptions and from the drawings.  
         SUMMARY OF THE INVENTION  
         [0019]    This invention is an improved device for providing pneumatic cushioning within a shoe sole. The invention represents a significant advance over the state of the art by providing a shoe sole which encompasses every necessary component for adjustable pneumatic cushioning.  
           [0020]    The device includes a pump which is entirely within the sole, a pump actuator which is entirely within the sole when not in use, and an inflatable bladder which is entirely within the sole and is operatively connected to the pump.  
           [0021]    The inventive device can further include a locking mechanism which secures the pump actuator within the sole. It is preferred that the pump actuator can be locked only when the pump-actuator cap is flush with the outer wall of the sole. Such an arrangement facilitates use of the locking mechanism by the shoe wearer. The locking mechanism is finger-operated to further facilitate use by the shoe wearer.  
           [0022]    The pump actuator preferably includes a piston rod having a distal end which is attached to the pump-actuator cap. The cap is rotatably movable between locked and unlocked positions only when the cap is flush with the sole. The cap is movable in this position due to the structure of the piston rod. The piston rod includes at least one radially extending portion which also extends axially from the piston towards the cap. However, the radially extending portion does not reach the cap, rather, there exists a gap adjacent the cap.  
           [0023]    The pump-cylinder top includes a slot which is sized to accept the piston rod and the radially extending portion. The piston rod can be moved in and out of the pump-cylinder freely. However, if the piston rod is inserted so that the radially extending portion moves completely past the pump-cylinder top, the rod can be rotated so that the radially extending portion is not positioned in-line with the slot. Thus, the pump actuator is locked in position within the pump cylinder.  
           [0024]    The device is preferably positioned such that the pump is between the forefoot-pressure portion and the heel-pressure portion which strikes the ground first during walking or running by a typical shoe-wearer. This positioning prevents the pump from being damaged during the lifetime of the shoe.  
           [0025]    The device is also preferably positioned such that the pump is oriented transverse to the longitudinal axis which passes from the heel to the toes. The device is more preferably oriented substantially perpendicular to that longitudinal axis.  
           [0026]    The device is further preferably positioned in the midsole of the sole. The midsole being located between the outer sole which contacts external surfaces and the in sole which can typically be removed by the shoe-wearer.  
           [0027]    The preferred bladder includes a bladder membrane which has an interior and exterior side, a foam core contained within the bladder and having a plurality of sides, and adhesive disposed on only one side of the foam core, and a portion of the interior side of the bladder membrane adhering to the adhesive.  
           [0028]    The inflation device preferably further comprises an inlet conduit within the sole and connecting the pump to the bladder, a unidirectional flow valve between the inlet conduit and the bladder, a pressure-release valve within the sole and operatively connected to the bladder to permit the release of air from the bladder, and an exit conduit connecting the pressure-release valve to the bladder.  
           [0029]    In order to minimize the bulk of the shoe, it is most preferred that the pump be positioned at least partially within the bladder. More preferably, the pump is positioned entirely within the bladder. In such a preferred embodiment, first and second inlet conduits have distal ends connected to the first and second bladders and proximal ends connected to a flow switching device, first and second unidirectional flow valves are disposed, respectively, within the first and second conduits and between the flow switching device and the first and second bladders, respectively, and first and second pressure release valves are operatively connected, respectively, to the first and second bladders.  
           [0030]    The preferred device may also include a third bladder connected to the flow switching device by a third conduit; a third unidirectional flow valve between the flow switching device and the third bladder; and a third pressure release valve connected to the third bladder.  
           [0031]    The invention also includes a pneumatically cushioned shoe having a sole and comprising a pump which is entirely within the sole, a pump actuator which is entirely within the sole when not in use, and an inflatable bladder which is entirely within the sole and is operatively connected to the pump. The pump actuator preferably includes a locking mechanism securing the pump actuator within the sole. The pump actuator more preferably includes a piston rod having a distal end with the locking mechanism including a finger-operated cap which is attached to the distal end. The cap is movable between locked and unlocked positions only when the cap is flush with the sole as discussed above.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0032]    [0032]FIG. 1 is a general schematic of the inflating arrangement utilized in the shoe.  
         [0033]    [0033]FIG. 2 is a horizontal cross section of the shoe sole, revealing the inflation bladders and conduits.  
         [0034]    [0034]FIG. 3 is a side view of the shoe showing transparent conduits and the flow switching device.  
         [0035]    [0035]FIG. 4 shows a side bellows air pressurization unit coupled with an air release valve and a flow switching device.  
         [0036]    [0036]FIG. 5 shows the air pressurization unit in the closed position.  
         [0037]    [0037]FIG. 6 shows the air pressurization unit in the open position.  
         [0038]    [0038]FIG. 7 is a sectional view of a switching input device.  
         [0039]    [0039]FIG. 8 is a sectional view of the switching input device in a second position.  
         [0040]    [0040]FIG. 9 is a sectional view of the switching device in a closed position.  
         [0041]    [0041]FIG. 10 is a sectional view of a bladder with a foam core.  
         [0042]    [0042]FIG. 11 is a horizontal cross section of the shoe sole, revealing the inflation bladder and conduits.  
         [0043]    [0043]FIGS. 12A is prospective view of a side of the inventive shoe.  
         [0044]    [0044]FIGS. 12B is a prospective view of the back of the inventive shoe.  
         [0045]    [0045]FIGS. 13A is a side view of the piston rod and cap disconnected.  
         [0046]    [0046]FIGS. 13B is a prospective view of the pump actuator and pump cylinder.  
         [0047]    [0047]FIGS. 13C is a side view of the pump cylinder and pump-cylinder top disconnected. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0048]    The present invention is directed to a shoe with a pneumatic inflating device disposed therein. The general schematic of the shoe inflating arrangement is shown in FIG. 1 and includes three bladder sets. However, it will be apparent that the arrangement is adaptable to any plurality of bladder sets. The arrangement includes a pump  12  with an inlet  14  and an outlet  16 . Outlet  16  is connected to a flow switching device  18  at a flow switching input  20 . Flow switching device  18  operates as a selective valve which allows air flow into at least two outlets, the preferred embodiment having a first outlet  22 , a second outlet  24 , and a third outlet  26 . Each outlet  22 ,  24 , and  26  is connected to a corresponding conduit  28 ,  30 , and  32 . Each conduit  28 ,  30 , and  32  is associated with corresponding unidirectional flow valves  34 ,  36 , and  38 . Each unidirectional flow valve  34 ,  36 , and  38  is connected to corresponding conduit  40 ,  42 , and  44 . Each conduit  40 ,  42 , and  44  is further associated with corresponding pressure release valves  46 ,  48 , and  50 . Conduits  52 ,  54 , and  56  are connected to release valves  46 ,  48 , and  50  and each conduit is connected to corresponding bladder sets  58 ,  60 , and  62 .  
         [0049]    [0049]FIG. 2 shows one arrangement of separate bladder sets  58 ,  60  and  62  in the sole of shoe  100  in which forefoot bladder  62  is comprised of mid-forefoot bladder  64  and toe forefoot bladder  66 . Bladders  64  and  66  are interconnected by conduits  68  and  70 . This multiple bladder configuration may also be implemented on the other bladder sets.  
         [0050]    To pressurize the pneumatic system, the wearer preferably engages outlet  16  of pump  12  with switching input  20 . Pump  12  is mounted on a base portion  74  in which inlet  14  comprises an orifice  76  having an unidirectional inlet valve  78 . As the bellows  82  is lifted, the change in volume of air chamber  80  causes a corresponding reduction in pressure, thus causing air to flow through orifice  76  and valve  78  into chamber  80 . Bellows  82  is operatively connected with cover  84  pivotally connected at hinge portion  86 . Cover  84  is latchable to lock  88  through means of flange  90  engaging lock  88 . Cover  84  is releasable through use of a semi-rigid material in its construction which will enable flexing and thereby cause disengagement of flange  90  from latch  88 . The wearer then compresses bellows  82  which allows air flow into switching input  20 . This in turn allows air to fill the selected bladder set via flow switching device  18  in which the wearer can selectively control the air input to bladder sets  58 ,  60 , and  62 . The wearer may also adjust the pressure in each bladder set via the respective pressure release valve.  
         [0051]    The invention can be adapted to utilize a number of different combinations of elements to effectuate the goals of the invention. Thus, in FIG. 3, pump  12  could utilize an integral heel mounted plunger-type pump, as taught in U.S. Pat. No. 5,222,312, which is incorporated by reference herein. The plunger type pump could also be disposed in the sole of the shoe, or for that matter, located at any convenient place on the shoe. As an alternative to the plunger-type pump  12 , the bellows-type pump of FIGS. 4, 5, and  6  could also be used.  
         [0052]    Another variation is in the use, in the alternative, of different arrangements for flow switching device  18 . A first embodiment could utilize a simple “lie” type flow switching device in which pressure at input  20  is applied equally at each of conduits  52 ,  54 , and  56  applying equilibrium pressure at  20  using pump  12  and valves  34 ,  36 , and  38  would result in equal pressurization of each bladder arrangement  58 ,  60 , and  62 . Customization of pressures could be accomplished by the simple expedient of bleeding off high pressure to reduce pressure in one or more of the selected bladder arrangements  58 ,  60 , and  62 . Well known valves of the Schrader type could be utilized with push button release or variations such as the Presta type which is effectively lockable for the tightening of a threaded collar on the valve needle.  
         [0053]    A second alternative is to use a specially designed flow switching device having both flow directional control and valving control. Thus, switching device  118  in FIGS. 7, 8, and  9  uses rotor  122  contained within circumferential wall  124  of body  126  of device  118 . Body  126  also has a floor  128  and a top (not shown) to completely define an enclosed plenum  130 . Rotor  122  is sealed against wall  126  in such manner that rotor  122  may be turned in a plurality of positions. In FIG. 7, inlet chamber  132  is aligned with inlet  20  and in communication with passageway  134  that, in FIG. 7, further communicates to outlet  24 . By comparison, in FIG. 8, rotor  122  has been turned so that conduit  134  is now in communication with outlet  22  while chamber  132  owing to its elongated configuration. In FIG. 9, rotor  122  has been further turned so that both chamber  132  and conduit  134  abut wall  126 , thereby restricting passage of air between inlet  20  and any of outlets  22 ,  24 , or  26 . In like manner, of course, the rotor could be aligned with outlet  26  and inlet  20 . It is also possible to adapt flow switching device  118  to a greater or lesser number of outlets, as desired. In the preferred embodiment, outlets  22 ,  24 , and  26  would be associated with valves  34 ,  36 , and  38 , respectively. As described above, these could be of the Schrader or other improved Schrader types. Use of this approach in addition to the positional adjustment of rotor  122  to the closed position as shown in FIG. 9 would minimize pressure loss from bladders  58 ,  60 , and  62 .  
         [0054]    Nevertheless, with the use of suitable sealing materials, and an integral pump, the user could dispense with all valves save the flow switching device  118 . Use of a resilient, air impervious rotor  122  could provide self-sealing while appropriate coatings or seals, in the nature of gaskets or O-rings, could also be utilized.  
         [0055]    An additional variation would be to use a separable pump. This would save the user the bulk of having an attached pump, further enabling the use of a larger capacity pump obviating bulk or weight concerns and enabling the use of higher strength or more economical materials than would be desirable with an integral, attached pump. Use of a separable pump would be more likely to take advantage of the use of a valve  72  associated with inlet  20 , in the manner shown in FIG. 5.  
         [0056]    The bladders  58 ,  60 , and  62  can be any plastic envelope. The bladder membranes forming the envelope are resistant to the passage of gas molecules but need not be totally impermeable. The gas within the bladder should not escape so rapidly that re-inflation of the bladder will be needed more often than every thirty minutes of use. The bladder may also contain a foam core  61  where the foam may be any foam such as ethyl vinyl acetate, polyurethane, a composite using these materials, or any other resilient sponge material known or that may become known in the footwear industry. One face of the foam core is secured to one interior wall or surface of the bladder. In the preferred embodiment shown in cross section in FIG. 10, the top surface of the foam core  61  is secured by an adhesive  63  to the interior surface of the top membrane  55  of the inflatable bladder  57 . The adhesive  63  may be contact cement, heat activated cement, or solvent based cement. Alternatively, the bladder membrane may be attached to the foam core  61  by heat or radio welding.  
         [0057]    Alternative embodiments are the attachment of the bladder membrane to the sides of the foam core or attachment of the lower membrane in the lower surface of the foam element.  
         [0058]    [0058]FIGS. 11, 12A and  12 B, and  13 A,  13 B and  13 C depict the preferred inflation device disposed completely within the shoe sole.  
         [0059]    [0059]FIG. 11 is a horizontal cross section of the shoe sole, revealing the inflation bladder and conduits. The embodiment shown includes only one inflatable bladder  58 .  
         [0060]    Pump  12  is received within the recess occupied by bladder  58  so that the space necessary for pump  12  is minimized. Pump  12  is positioned substantially perpendicular to the axis passing from the heel to the toes. Pump  12  is positioned between heel-pressure portion  250  and forefoot-pressure portion  260  so that pump  12  is not damaged through normal shoe use.  
         [0061]    Pump actuator  210  is positioned within pump  12  (and is shown in phantom withdrawn from pump  12 ). Actuator  210  comprises a piston rod  230  with at least one radially extending side  234 . Radially extending side  234  fits within slot  280  on cylinder top  242  so that piston rod  230  may be moved in and out of pump cylinder  240 . Piston rod  230  includes gap  236  which is positioned between cap  200  and radially extending side  234 . When pump actuator  210  is inserted completely within the shoe sole, slot  260  and gap  236  are juxtaposed, thus allowing pump actuator  210  to be rotated. When radially extending side  234  is moved to a position not in-line with slot  236 , pump actuator  210  cannot be withdrawn from pump cylinder  240  and is locked in position. As shown in FIG. 12A, cap  200  can be moved in the direction of the arrows to either lock or unlock pump actuator  210 . Cap  200  is flush with the outer wall  220  of the sole when pump actuator  210  is locked in position.  
         [0062]    As shown in FIG. 13C, cylinder top  242  is removable from pump cylinder  240  to allow for the insertion of pump actuator  210  therein. Cylinder  242  is thereafter sufficiently secured to cylinder  240  to prevent non-intentional removal thereof.  
         [0063]    [0063]FIG. 13A depicts cap  200  disengaged from distal end  232  of piston rod  230 . In use cap  200  is sufficiently secured to rod  230  so that separation does not occur. Piston  238  is sized such that movement into cylinder  240  causes air to be force out of the pump chamber into the bladder.  
         [0064]    Pump  12  is connected to bladder  58  via inlet conduit  28  and unidirectional valve  34 . Unidirectional valve  34  prevents air from escaping bladder  58  back into inlet conduit  28 . Bladder  58  is connected to pressure-release valve  46  via exit conduit  52 .  
         [0065]    Although the configuration depicting the inflating device being positioned entirely within the sole has only one set of bladder, inlet and exit conduit, and pressure-release valve, it is understood that such a inflating device could be used with each of the above-described configurations which utilize more than one such set.  
         [0066]    Thus, it should be apparent that there has been provided, in accordance with the present invention, a shoe and inflation device for easily providing pneumatic cushioning in the shoe sole that fully satisfy the objectives and advantages set forth above.  
         [0067]    Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.