Patent Publication Number: US-7213353-B1

Title: Footwear cushioning attachment

Description:
FIELD OF THE INVENTION 
   The invention herein pertains to absorbing impact and particularly pertains to a footwear attachment for use by parachutists to reduce injuries during landing. 
   DESCRIPTION OF THE PRIOR ART AND OBJECTIVES OF THE INVENTION 
   The feet, ankles, legs, knees, back and other areas of the body of parachutists are sometimes injured as they often strike the ground at a high velocity. Multiple, partial and total disability claims are paid each year by the Federal Government as the result of these injures to paratroopers, burdening medical facilities, tax payers and driving up the national debt. Previous attempts have been conceived to minimize such injuries such as set forth in U.S. Pat. No. 5,675,915. Use of high density urethane foam soles as described to absorb impact is beneficial under certain circumstances, however the present invention provides a different structure and advantages over those known to be old. 
   Thus, the present invention was conceived and one of its objectives is to protect the lower extremities and back of a parachutist when impacting the ground upon landing. 
   It is another objective of the present invention to provide an attachment for the parachutists&#39; footwear which can be readily donned or removed within seconds. 
   It is also an objective of the present invention to provide an attachment for footwear which can be used multiple times without decreasing in effectiveness. 
   It is still another objective of the present invention to provide an attachment for parachutist&#39;s footwear which includes a reservoir having a fluid filled cavity whereby the fluid is dispelled therefrom proportional to the rate of impact. 
   Various other objectives and advantages of the present invention will becomes apparent to those skilled in the art as a more detailed description is set forth below. 
   SUMMARY OF THE INVENTION 
   The aforesaid and other objectives are realized by providing a polymeric footwear attachment for parachutists to cushion the impact upon landing for injury elimination and reduction. The attachment includes a reservoir formed from a somewhat flexible material such as polyvinyl chloride with a fluid cavity therein. The devices are shaped similarly to the soles of the left and right parachutists&#39; boots and may include a top ridge around the perimeter for stabilization of the attachment during wear. The reservoir includes a pair of adjustable straps which are affixed along the sides and each strap includes a top section of hook and loop fastener material. By placing the boot on the top of the attachment the straps or handles can be brought together and affixed by the hook and loop fasteners to secure the attachment on the boot. At the rear of each reservoir is a port which is in communication with the internal fluid cavity. The port is used for filling and refilling the cavity with a fluid such as water and a conically shaped blowout plug is then inserted to maintain the water therein. The fluid cavity extends substantially the entire length of the reservoir and has a depth of 0.625–1.25 cm. The blowout plug is frictionally engaged within the port so the parachutist can walk as normal without dispelling the blowout plug and fluid, such as prior to jumping from a plans. 
   Once the parachutist exits the plane and impacts the ground, the reservoirs flex to drive the blowout plugs and fluid from the reservoirs. The rate of fluid release from the reservoir cavity is dependent upon the force of impact and diameter of the exit apertures, thereby cushioning the lower extremities and reducing the chances of bodily injury. Once the parachutist has landed the straps on the attachments can be quickly, manually released and the attachments removed from the parachutist&#39;s boots and later refilled with fluid and replugged for reuse when the parachute is replaced. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a typical parachutist&#39;s right boot with the cushioning attachment of the invention affixed thereto; 
       FIG. 2  demonstrates schematically the cushioning attachment without straps as removed from the footwear with the blowout plug as seen on initial impact with the ground; 
       FIG. 3  schematically illustrates the attachment as seen in  FIG. 2  at a slightly later time during impact with the attachment in a compressed state during fluid dissipation; 
       FIG. 4  depicts a top view of the attachment as seen in  FIG. 1  with the footwear removed therefrom; 
       FIG. 5  pictures a top view of the footwear and attachment as shown in  FIG. 1  along line  5 — 5 ; and 
       FIG. 6  demonstrates a front view of the footwear and attachment as shown in  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT AND OPERATION OF THE INVENTION 
   For a better understanding of the invention and its operation, turning now to the drawings,  FIG. 1  illustrates the preferred form of footwear cushioning attachment  10  having reservoir  11  ( FIG. 2 ) therewithin formed from a somewhat flexible polymeric material, such as a durable polyvinyl chloride through other suitable materials may be used. Reservoir  11  preferably has an overall height of approximately 2.54 cm and includes inner fluid cavity  12  as shown in  FIG. 2  which is in fluid communication with rear port  13  shown with conically shaped blowout plug  14 . Multiple blowout plugs  14  may be used as desired and each blowout plug  14  could include a tether (not shown) which is attached to reservoir  11  to prevent loss. Cavity  12  preferably has a height of about 0.625–1.25 cm and extends substantially the entire length of reservoir  11 . Other cavity volumes may be necessary, depending on the users and materials selected for the manufacture of reservoir  11 . As would be understood, reservoir  11  would be made in various shapes and sizes to accommodate different shapes and footwear sizes for particular uses. 
   Adjustable straps  15 ,  15 ′ are attached to the sides of reservoir  11  as by integrally forming during manufacturing or by ultrasonic welding or other conventional methods as selected by skilled manufacturing personal. Straps  15 ,  15 ′ are also formed of polyvinyl chloride and can be releasably joined to each other by hook and loop fasteners  16 ,  16 ′ thereon as shown in  FIG. 4 . Buckles  18 ,  18 ′ are used to adjust the length of straps  15 ,  15 ′ respectively. 
   As schematically illustrated in  FIG. 2 , as attachment  10  initially strikes the ground or other surface to strongly impact the same, blowout plug  14  exits port  13  and fluid such as water  20  therein is beginning release to cushion or absorb the impact.  FIG. 3  demonstrates footwear cushioning attachment  10  in schematic form at a slightly later time after full impact, with reservoir  11  and cavity  12  collapsed and with water  20  dispelled therefrom. Water  20  is the preferred fluid for use, though other fluids, liquids and the like may be used for specific conditions and environments. 
   Lip  17  surrounds the top of attachment  10  to maintain boot  30  in a stable posture when positioned on attachment  10 . Lip  17  is approximately 0.3–0.6 cm in height and cap be integrally formed with reservoir  11  during molding or other manufacturing technique. U-shaped adjustable straps  15 ,  15 ′ are adjustable by conventional buckles  18 ,  18 ′ as shown in  FIG. 4 . Straps  15 ,  15 ′ may be formed from a thin, flexible polyvinyl chloride and directly molded to reservoir  11 . As seen in  FIGS. 4 and 5 , straps  15 ,  15 ′ are releasably affixed across the top of boot  30 . 
   While only the right boot is shown in  FIGS. 1–6 , as would be understood an identical attachment in mirror image form would be provided for the parachutist&#39;s left boot or other footwear. 
   In use, a parachutist would affix right footwear cushioning attachment  10  and a left footwear cushioning attachment (not shown) to the bottom of hit boots as shown in  FIG. 1  during flight. Attachment  10  is designed for normal walking so blowout plug  14  remains in place as shown in  FIG. 1 . Upon jumping from the plane and impacting the ground below, high pressure derived from striking the ground causes water  20  within cavity  12  to force blowout plug  14  from rear port  13  thereby allowing water  20  to quickly exit. Exiting of water  20  allows reservoir  11  to controllably collapse, thus softening the impact on the lower extremities, back and other body areas. 
   The footwear cushioning attachments described herein may be used for other activities, other than for parachuting as desired. Thus, changes are anticipated by those skilled in the art for specific conditions, functions and activity needs and the illustrations and examples provided herein are for explanatory purposes only and are not intended to limit the scope of the appended claims.