Abstract:
A housing has an upper end, a lower end, and an opening extending between the upper and lower ends, the housing being sealingly attachable to an inflatable device. A check valve has a body member with an upper end, a lower end, an outer surface sized and shaped to be selectively matingly received in the opening of the housing, and an inner surface defining a passageway. The check valve is coupled to the housing by a first tether. A cap has an upper end, a lower end, and an outer surface sized and shaped to be selectively matingly received in the passageway of the check valve. The cap is coupled to the housing by a second tether.

Description:
FIELD OF THE INVENTION 
       [0001]    The apparatus described herein is generally directed to the field of valves; and, more directly, to the field of air valves for inflatable devices. 
       BACKGROUND OF THE INVENTION 
       [0002]    The use of inflatable devices has long been associated with water sports and recreational activities involving water. For the most part, this has been the case because inflatable devices are generally capable of floating on water. With the explosion of the availability of inexpensive plastic products, recreational devices such as beach balls and water wings became increasingly common at pools and beaches during the latter half of the 20 th  century. 
         [0003]    Inflatable devices have also been used for more sophisticated recreational purposes. For example, inner tubes have traditionally been used as a simple watercraft. Inner tubes float in water, even with a rider in place, and provide a relatively ergonomic shape to secure the rider comfortably. They are also sufficiently durable for this use. Inner tubes can be used to float in a calm body of water, or they can be used as passive vehicles in a flowing body of water, such as a river. Inner tubes can also be towed behind powered watercraft. These activities are known as “tubing.” 
         [0004]    Inner tubes are well suited for water recreation, especially given that they were not designed for this use. However, they have several drawbacks, which in part result from being used outside of their design specifications. One major drawback is that they are designed to be inflated at a high pressure. This means that a high pressure pump must be used to inflate them. This also means that it takes a relatively long time to inflate and deflate inner tubes. There is also a risk of violent rupture because of the high potential energy of a high pressure reservoir. Such an event could cause human injury or property damage. 
         [0005]    As a result, there has been a move to produce simple watercraft and other water recreation devices from PVC instead of rubber, as in an inner tube. Watercraft and devices in this newer wave tend to be low pressure inflatables. They also incorporate design improvements in ergonomics and maneuverability for recreational use. 
         [0006]    Despite being inflated to a low pressure, these devices often have a substantial volume of inflatable space. This makes fast and easy inflation and deflation an engineering challenge. Most of the design work that goes in to addressing this challenge is focused on the air valves for these devices. The valves must be able to accommodate a large flow volume for both inflation and deflation. They must be air tight when closed, even during hard use or stressful conditions. Furthermore, they must accommodate inflation from sources not capable of producing high inflation pressures. Thus, there remains a need in the art for air valves for inflatable devices that meet these design requirements. 
       SUMMARY OF THE INVENTION 
       [0007]    A housing has an upper end, a lower end, and an opening extending between the upper and lower ends, the housing being sealingly attachable to an inflatable device. A check valve has a body member with an upper end, a lower end, an outer surface sized and shaped to be selectively matingly received in the opening of the housing, and an inner surface defining a passageway. The check valve is coupled to the housing by a first tether. A cap has an upper end, a lower end, and an outer surface sized and shaped to be selectively matingly received in the passageway of the check valve. The cap is coupled to the housing by a second tether. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is an inflatable device incorporating one embodiment of the air valve. 
           [0009]      FIG. 2  is blown-up view of the air valve shown in  FIG. 1 . 
           [0010]      FIG. 3  is a perspective view of the embodiment of the air valve shown in  FIG. 2  in a fully opened position. 
           [0011]      FIG. 4  is a cross-section of the embodiment shown in  FIG. 2  in a fully opened position. 
           [0012]      FIG. 5  is a perspective view of the embodiment shown in  FIG. 2  in a partially opened position. 
           [0013]      FIG. 6  is a cross-section of the embodiment shown in  FIG. 2  in a partially opened position. 
           [0014]      FIG. 7  is a perspective view of the embodiment shown in  FIG. 2  in a closed position. 
           [0015]      FIG. 8  is a cross-section of the embodiment shown in  FIG. 2  in a closed position. 
           [0016]      FIG. 9   a  is a perspective view of a second embodiment of the air valve in a fully opened position. 
           [0017]      FIG. 9   b  is a perspective view of the embodiment shown in  FIG. 9   a  in a partially opened position. 
           [0018]      FIG. 9   c  is a perspective view of the embodiment shown in  FIG. 9   a  in a closed position. 
           [0019]      FIG. 10   a  is a perspective view of a third embodiment of the air valve in a fully opened position. 
           [0020]      FIG. 10   b  is a perspective view of the embodiment shown in  FIG. 10   a  in a partially opened position. 
           [0021]      FIG. 10   c  is a perspective view of the embodiment shown in  FIG. 10   a  in a closed position. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]      FIG. 1  is an inflatable device  100  incorporating one embodiment of the air valve  110 . Inflatable device  100  may be a watercraft, floating lounge, air mattress, inflatable pool, or a variety of other devices. Inflatable device  100  comprises an air reservoir  120 , which typically must be filled with air at or above the pressure in the surrounding environment to perform some intended function. Air valve  110  is the device that enables inflation and deflation of inflatable device  100 . Air is transferred to and from air reservoir  120  through air valve  110 . Air valve  110  must provide a passageway for delivery of air, but must also be capable of retaining air within air reservoir  120  at pressure when inflation is complete. One advantage of an inflatable device having an air valve over an inflated device not having an air valve (such as a balloon) is that an inflatable device can be “topped off” or re-inflated to the maximum pressure if the relative pressure subsides due to leakage, distention of the air reservoir, or a decrease in atmospheric pressure (due to weather or altitude changes, for example). Another advantage is that inflatable device  100  is also capable of being deflated for easy transport and storage. The presence of air valve  110  on inflatable device  100  makes inflatable device  100  capable of being re-inflated or “topped off” and deflated.  FIG. 2  is blown-up view of air valve  110  shown in  FIG. 1 . 
         [0023]      FIG. 3  is a perspective view of the embodiment of air valve  110  shown in  FIG. 2  in a fully opened position. Air valve  110  comprises housing  300 . Housing  300  comprises opening  410 . A check valve  340  is coupled to housing  300  via a first tether  310 . A cap  350  is coupled to housing  300  via a second tether  320 . In this embodiment, second tether  320  is coupled to housing  300  at a 90 degree angle with respect to first tether  310 . In other embodiments, second tether  320  is coupled to housing  300  at any angle with respect to first tether  310 . 
         [0024]    First pull tab  330  is on an outward end of first tether  310 , with check valve  340  intermediate first pull tab  330  and housing  300 . First pull tab  330  and first tether  310  are one continuous piece having a first hole  392 . First hole  392  couples check valve  340  to first tether  310 . First tether  310  is coupled to an inward end of check valve  340  and first pull tab  330  is coupled to an outward end of check valve  340 . In one embodiment, check valve  340  has a first annular groove on its upper end. The first annular groove in that embodiment is arranged to couple check valve  340  to first tether  310 . The first annular groove has an inner diameter that is the same as the diameter of first hole  392 . In that embodiment, first hole  392  has a smaller diameter than the outer surface of check valve  340 . This allows a secure coupling of check valve  340  to first tether  310 . Second pull tab  380  is on an outward end of second tether  320 , with cap  350  intermediate second pull tab  380  and housing  300 . Second pull tab  380 , second tether  320 , and cap  350  are made from a single continuous piece. 
         [0025]      FIG. 4  is a cross-section of the embodiment shown in  FIG. 2  in a fully opened position. In the illustrated embodiments, check valve  340  is a boston valve. A boston valve comprises a perforated plate  400  with an abutting flexible disc  370 . Flexible disc  370  is on the reservoir side and the perforated plate  400  is on the atmospheric or external side. During inflation, the pressure is greater on the outer side than the reservoir side. The pressure differential induces a flow through perforated plate  400 . This flow is only resisted by the rigidity of flexible disc  370 , which is small. Therefore, the air flow easily deforms flexible disc  370  such that it no longer obstructs the perforations in perforated plate  400 . Air then flows from the high pressure outer side to the low pressure reservoir  120  with relatively little resistance. When an external pressure source is removed, reservoir  120  will be at a higher pressure than the atmosphere or the outside of check valve  340 . In this condition, the flow is reversed and flexible disc  370  is deformed, however it is deformed towards the perforations instead of away from them. Therefore, the high pressure air forces flexible disc  370  to cover the perforations, preventing the flow of air. Thus the boston valve is a one-directional valve comprising flexible disc  370  which is arranged to selective engage perforated plate  400  when pressure within inflatable device  100  exceeds pressure on the outside of inflatable device  100 . Other embodiments may not use a boston valve, and may use some other type of valve. 
         [0026]    Check valve  340  includes annular rim  390  which is adapted to mate with a second annular groove  430  when check valve  340  is inserted into opening  410 . This ensures that the fit between check valve  340  and opening  410  is secure and air-tight. Housing  300  comprises an upper end  440  and a lower end  450 . In one embodiment, lower end  450  is sealingly attached to inflatable device  100 . 
         [0027]      FIG. 5  is a perspective view of the embodiment shown in  FIG. 2  in a partially opened position.  FIG. 6  is a cross-section of the embodiment shown in  FIG. 2  in a partially opened position.  FIG. 7  is a perspective view of the embodiment shown in  FIG. 2  in a closed position.  FIG. 8  is a cross-section of the embodiment shown in  FIG. 2  in a closed position. In this embodiment, second tether  320  is coupled to housing  300  at a 90 degree angle with respect to first tether  310  as viewed from above air valve  110  as if looking through air valve  110  into inflatable device  100 . 
         [0028]    To inflate reservoir  120 , a user folds first tether  310  and inserts check valve  340  into opening  410  in housing  300  as shown in  FIG. 5 . The user then inflates the reservoir through check valve  340  either using human lung power or a mechanical pump. When a user has inflated inflatable device  100  to desired volume or pressure, the user removes the source of pressurized air. As discussed above, check valve  340  prevents the escape of air from reservoir  120  in this condition. The user then folds second tether  320  and places cap  350  into passageway  420  in check valve  340  to fully close air valve  110  as shown in  FIG. 7 . This prevents debris or fluids from entering check valve  340 , or inadvertent opening of check valve  340 , or damage to check valve  340 . Cap  350  also provides an extra barrier to the escape of air from reservoir  120 . In this final position, air valve  110  is in a closed position and inflatable device  100  is ready for use. A user may top off the pressure in inflatable device  100  or access check valve  340  for some other reason by removing cap  350  from passageway  420  and leaving check valve  340  in place (i.e. the partially opened position) as shown in  FIG. 5 . It is easy for a user to remove or insert cap  350  without disturbing check valve  340  or inadvertently deflating air reservoir  120  because the two parts are independently tethered to housing  300 . 
         [0029]    In order to deflate air reservoir  120 , a user first removes cap  350  from passageway  420  by pulling second pull tab  380 . Second, the user removes check valve  340  from opening  410  by pulling first pull tab  330 . This allows air to escape through opening  410  in housing  300 , which is a relatively short passageway with a relatively large diameter. Thus, air encounters little resistance as it escapes from the reservoir. As a result, opening  410  facilitates rapid deflation of inflatable device  100 , which is advantageous to a user. 
         [0030]      FIG. 9   a  is a perspective view of a second embodiment of the air valve in a fully opened position.  FIG. 9   b  is a perspective view of the embodiment shown in  FIG. 9   a  in a partially opened position.  FIG. 9   c  is a perspective view of the embodiment shown in  FIG. 9   a  in a closed position. First tether  310  and second tether  320  may be coupled to opposite sides of housing  300 . When air valve  110  is in a closed position, first pull tab  330  is adapted to fit between, on one side, check valve  340  and, on the other side, second tether  320  and second pull tab  380 . First pull tab  330  is sufficiently thin to fit in between these parts in a closed position. First pull tab  330  is also shaped so as to fit into air valve  110  in a streamlined manner when air valve  110  is in a closed position. In this embodiment, first pull tab  330  is a flattened ring and surrounds cap  350  in a closed position of air valve  110 . First pull tab  330  can be any shape that is ergonomic to pull and can fit between cap  350  and check valve  340  in a closed position. 
         [0031]    First pull tab  330  has a second hole  900  which is shaped to allow cap  350  to be inserted through second hole  900  before being inserted into passageway  420 . In order to close this embodiment of air valve  110 , a user must fold over first pull tab  330 , insert cap  350  through second hole  900 , and insert cap  350  into passageway  420 . In one embodiment, second hole  900  is the same shape as the cross-section of cap  350  or sized and shaped to closely receive cap  350 . Once in a closed position, first pull tab  330  is held securely in place by second tether  320  and second pull tab  380 . 
         [0032]      FIG. 10   a  is a perspective view of a third embodiment of the air valve in a fully opened position.  FIG. 10   b  is a perspective view of the embodiment shown in  FIG. 10   a  in a partially opened position.  FIG. 10   c  is a perspective view of the embodiment shown in  FIG. 10   a  in a closed position. In this embodiment, first tether  310  and second tether  320  are coupled to opposite sides of housing  300 . In this embodiment, second tether  320  comprises orifice  1000  adjacent to housing  300 . Orifice  1000  provides clearance for first pull tab  330 , so that in a closed position of air valve  110 , first pull tab  330  protrudes from orifice  1000 . First pull tab  330  can be any shape that is ergonomic to pull and does not interfere with second tether  320  in a closed position. 
         [0033]    Although the invention has been described with reference to embodiments herein, those embodiments do not limit the scope of the invention. Modification to those embodiments or different embodiments may fall within the scope of the invention.