Abstract:
An inflatable sport ball, such as a basketball, a football, a soccer ball, a volleyball or a playground ball, is provided with a self-contained inflation mechanism, or multiple self-contained inflation mechanisms, for inflating or adding pressure to the ball. The mechanism is a pump which is positioned and retained inside of the ball and which is operable from outside of the ball to pump ambient air into the ball. The pump is a dual action pump allowing air to be added to the ball on both a forward stroke and a reverse stroke.

Description:
The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/435,222 filed on Dec. 20, 2002, and is a continuation-in-part of U.S. application Ser. No. 10/726,950, which was filed on Dec. 3, 2003. 

   FIELD OF THE INVENTION 
   The present invention relates to sport or game balls that contain integral mechanisms for inflating or adding pressure to the balls. The inflation mechanisms are double action pumps instead of the single action pumps currently available in certain inflatable sport balls. 
   BACKGROUND OF THE INVENTION 
   Conventional inflatable sport balls, such as basketballs, footballs, soccer balls, volleyballs and playground balls, are inflated through a traditional inflation valve using a separate inflation needle that is inserted into and through a self-sealing inflation valve on the ball. A separate pump, such as a traditional bicycle pump, is connected to the inflation needle and the ball is inflated using the pump. The inflation needle is then withdrawn from the inflation valve which then self-seals to maintain the air pressure within the ball. This system works fine until the ball needs inflation or a pressure increase and a needle and/or pump are not readily available. 
   More recently, inflatable sport balls have been developed that have integral pumps. But these pumps are only single action pumps. If a relatively large pressure increase is needed, it can be quite time consuming to add air and increase the ball&#39;s pressure. This is because the pumps are small and do not add a large volume of air with each stroke. 
   SUMMARY OF THE INVENTION 
   An object of the present invention is to inflate or add pressure to a sport ball without the need for separate inflation equipment such as a separate inflation needle and pump, and to be able to add the air more quickly by reducing the number of strokes otherwise needed. 
   The present invention provides a sport ball having a self-contained dual action inflation mechanism. The invention also provides a ball having multiple self-contained inflation mechanisms, in which at least one of the inflation mechanisms is of the dual action type. As used herein, a “dual action” or “double action” pump or inflation mechanism refers to a pump that adds air on both the in (or down) stroke and the out (or up) stroke. Restated, the dual action pump introduces air to the ball in both directions of the pumping action. 
   More specifically, the invention relates to a sport ball that has at least one self-contained pump device which is operable from outside the ball and which pumps ambient air into the ball to achieve a desired pressure. Additionally, the pump is a double action or dual action pump. The dual action of the pump allows air to be introduced into the interior of the inflatable sport ball on both the forward stroke and the reverse stroke by drawing air into separate chambers on each stroke. The dual action pump will be described in more detail below. The pump mechanism may also have a pressure relief mechanism and/or a pressure indication device. 
   In a first aspect, the present invention provides a sport ball having an integral pump. The ball comprises a flexible ball body adapted to retain pressurized air. The body defines an aperture. The ball also comprises a pump disposed in the aperture and retained within the ball body. The pump includes a cylinder defining a hollow interior. The pump also includes a piston disposed in the hollow interior of the cylinder. The piston defines a passage for air flow into the cylinder. The piston is movable between an extended position and an inserted position. The pump also includes a valve assembly which includes a first valve disposed in the passage defined in the piston. The first valve is configured to restrict air flow such that air may only enter the piston upon moving the piston toward an extended position. 
   In another aspect, the present invention provides an inflatable ball having an integral dual-action pump assembly for changing air pressure within the ball. The ball comprises a rubber bladder defining an interior region adapted for retaining pressurized air. The ball also comprises an outer layer disposed about the rubber bladder. Additionally, the ball comprises a pump assembly disposed in the interior region of the rubber bladder. The pump assembly includes a movable plunger sealingly disposed within a cylinder secured to the rubber bladder. The plunger is movable in both a forward stroke and a reverse stroke. The pump assembly is adapted to transfer air to the interior region of the rubber bladder by moving the plunger in either the forward stroke or the reverse stroke directions. The plunger defines a hollow passage along at least a portion of the length of the plunger. The plunger also includes a one-way valve disposed in the hollow passage. The one-way valve is configured to only permit air flow through the plunger and into the rubber bladder during movement of the plunger in the direction of a reverse stroke. 
   In yet another aspect, the present invention provides a dual action pump adapted for incorporation in an inflatable sport ball. 
   These and other objects and features of the invention will become apparent from the specification, drawings and claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The following is a brief description of the drawings, which are presented for the purposes of illustrating the invention and not for the purposes of limiting the same. 
       FIG. 1  is a partial cross-sectional view of a basketball utilizing a preferred embodiment dual action pump in accordance with the present invention. 
       FIG. 2  is a partial cross-sectional view of a football utilizing the preferred embodiment dual action pump in accordance with the present invention. 
       FIG. 3  is a detailed cross-sectional view of a portion of the basketball depicted in  FIG. 1  illustrating a preferred mounting configuration for the dual action pump of the present invention. 
       FIG. 4  is a detailed cross-sectional view of a plunger component of the preferred embodiment dual action pump. 
       FIG. 5  is a detailed cross-sectional view of a pump cylinder component of the preferred embodiment dual action pump. 
       FIG. 6  is a cross section of a preferred dual action pump according to the present invention illustrating air flow during a reverse stroke. 
       FIG. 7  is a cross section of the preferred dual action pump illustrating air flow during a forward stroke. 
       FIG. 8  is a perspective view of a preferred cylinder collar used for securing the dual action pump within a game ball. 
       FIG. 9  is a partial cross section of a game ball illustrating the mounting configuration between the dual action pump, the cylinder collar, and a boot. 
       FIG. 10  is a cross section of a preferred nozzle component for use in the dual action pump of the present invention. 
       FIG. 11  is a cross section of a preferred duckbill valve used in the nozzle component illustrated in  FIG. 10 . 
       FIG. 12  is another preferred embodiment of a game ball according to the present invention. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention relates to a sport or game ball having an integral dual action pump. The pump is retained within the ball and may be easily used to introduce air into the ball and thereby inflate the ball. 
   The pump preferably comprises three components, a cylinder, a piston disposed in the cylinder, and a valve assembly. The piston is movable within the cylinder between an extended position and an inserted position. The valve assembly includes a plurality of valves, described in greater detail herein, that enable air to be admitted into the ball during each direction of movement of the piston. That is, air is introduced into the ball during movement of the piston from an extended position to an inserted position. And, air is introduced into the ball during movement of the piston from the inserted position to the extended position. Furthermore, it is not necessary that the piston be displaced along the entire stroke length, i.e. between a fully extended position and a fully inserted position or vice versa. The unique pump of the present invention delivers air to the ball during movement in either direction of the piston. It will be appreciated however that some minimum or threshold degree of piston travel in either direction may be necessary to achieve a sufficient pressure to cause air to enter the ball. 
   Referring to  FIG. 1  of the drawings, a sport ball  10  is illustrated incorporating a preferred embodiment inflation pump  5  of the invention. The ball which is illustrated is one typical basketball construction comprising a carcass having a rubber bladder  12  for air retention, a layer  14  composed of layers of nylon or polyester yarn windings wrapped around the bladder  12  and an outer rubber layer  16 . As will be understood, “carcass” refers to the flexible body of the ball. For a laminated ball, an additional outer layer  18  of leather or a synthetic material may be used which preferably comprises panels that are applied by adhesive and set by cold molding to the rubber layer  16 . The windings  14  are randomly oriented and two or three layers thick, and they form a layer that cannot be extended to any significant degree. The layer formed by the windings  14  also restricts the ball  10  from expanding to any significant extent beyond its regulation size when inflated beyond its normal playing pressure. This layer  14  for footballs, volleyballs and soccer balls is referred to as a lining layer and is usually composed of cotton or polyester cloth that is impregnated with a flexible binder resin such as vinyl or latex rubber. The outer layer  18  may be stitched for some sport balls, such as a soccer ball or a volleyball. The outer layer may optionally have a foam layer backing or a separate foam layer. 
     FIG. 2  illustrates a football  110  incorporating an inflation pump  5  according to the present invention. The football  110  comprises a carcass having a rubber bladder  112  for air retention, and an outer layer  118  of leather or synthetic material. As will be appreciated, the carcass of the football  110  may include one or more additional layers such as a winding layer or reinforcement layer, a foam or backing layer, and a secondary rubber lining layer. 
   Other sport ball constructions, such as sport balls produced by a molding process, such as blow molding, may also be used in the invention. For an example of a process for molding sport balls, see, for example, U.S. Pat. No. 6,261,400, incorporated herein by reference. 
   Materials suitable for use as the bladder include, but are not limited to, butyl, latex, urethane, and other rubber materials generally known in the art. Examples of materials suitable for the winding layer include, but are not limited to, nylon, polyester and the like. Examples of materials suitable for use as the outer layer, or cover, include, but are not limited to, polyurethanes, including thermoplastic polyurethanes; polyvinylchloride (PVC); leather; synthetic leather; and composite leather. Materials suitable for use as the optional foam layer include, but are not limited to, neoprene, SBR, TPE, EVA, or any foam capable of high or low energy absorption. Examples of commercially available high or low energy absorbing foams include the CONFOR™ open-celled polyurethane foams available from Aearo EAR Specialty composites, Inc., and NEOPRENE™ (polychloroprene) foams available from Dupont Dow Elastomers. 
   Referring to  FIG. 3 , incorporated into the carcass of the ball  10  of the invention during its formation is a rubber pump boot or housing  20  that defines a central opening and an outwardly extending flange  22  which is preferably bonded to the bladder  12  using a rubber adhesive. The boot  20  is preferably located between the rubber bladder  12  and the layer of windings  14 . The boot  20  may be constructed of any suitable material, such as butyl rubber, natural rubber, urethane rubber, or any suitable elastomer or rubber material known in the art, or combinations thereof. A molding plug (not shown) is inserted into the boot opening during the molding and winding process to maintain the proper shape of the central opening and to allow the bladder  12  to be inflated during the manufacturing process. The molding plug is preferably aluminum, composite or rubber, and most preferably aluminum. The central opening defined through the boot  20  is configured with a groove  24  to retain a flange extending from the upper end of a pump cylinder described and illustrated later herein. The pump cylinder can optionally be bonded to the boot  20  using any suitable flexible adhesive (epoxy, urethane, cyanoacrylate, or any other flexible adhesive known in the art). 
   Referring to  FIGS. 4 and 5 , a preferred embodiment dual action pump according to the present invention comprises a plunger or piston  210  and a pump cylinder  240 . The pump cylinder  240  shown is a right cylinder, but other cylinders that are not right cylinders, such as a cylinder having a non-circular cross-section, may be used. Specifically, referring to  FIG. 4 , the plunger  210  includes a plunger body  220  having a cap  212  defined or formed on one end, a sealing end  232  opposite from the cap  212 , and a tubular wall  230  extending between the sealing end  232  and the cap  212 . The cap  212  defines an outer face  214 . The sealing end  232  defines an annular recess  234  along its outer surface. The tubular wall  230  defines a hollow interior defined by a circumferential interior surface  236  extending along the length of the plunger  210 , or at least substantially so. The hollow interior of the plunger  210  is accessible from both the sealing end  232  and the cap end  212 . As described in greater detail herein, a one-way valve  286  is disposed within the hollow interior of the plunger  210  and permits air flow through that interior in only one direction. 
   The pump cylinder  240  is generally in the shape of a right cylinder having two open ends and a unique sidewall configuration. Specifically, the cylinder  240  includes a head end  242 , a nozzle end  270 , and a generally cylindrical sidewall  246  extending therebetween. Defined along the head end  242  is a lip or flange  244 . The cylinder  240  also includes a base  272  proximate the nozzle end  270 . The inside of the cylinder  240  is generally hollow and is defined by an interior circumferential surface  290  which is the inner surface of the sidewall  246 . The sidewall  246  also defines an exterior surface, opposite from the interior surface  290 . The hollow interior of the cylinder  240  is also defined by an end wall  292  proximate the base  272 . 
   The base  272  of the cylinder  240  defines a discharge passage  274 . The passage  274  generally extends from the hollow interior of the cylinder  240  to the nozzle end  270  of the cylinder  240 . And so, upon incorporation of the pump into a ball, the discharge passage  274  provides communication between the interior of the cylinder  240  and the interior of the ball. 
   As noted, the sidewall  246  of the cylinder  240  features a unique passageway configuration. An intake  248 , is provided by a sidewall passage  252  extending between the intake  248  and a sidewall exit aperture  254 . The sidewall exit aperture  254  is defined near the base  272  of the cylinder  240 . A one-way valve  255  is fitted over the aperture  254  that only allows air to flow out of the interior of the pump cylinder  240 . It will be appreciated that although the valve  255  is depicted schematically in  FIG. 5 , preferably that valve is a one-way valve as described in greater detail herein. The cylinder  240  also defines a second passage  260  defined within a portion of the sidewall  246 . The passage  260  extends between an aperture  262  defined along the head end  242  of the cylinder  240  and an aperture  266  defined along the circumferential interior wall  290  of the cylinder  240 . A one-way valve  267  is disposed within the passage  260  and preferably near the aperture  266 . The function and configuration of the valve  267  is described in greater detail herein. 
   Upon assembly of the preferred embodiment dual action pump according to the present invention, the plunger  210  is inserted in the hollow interior of the cylinder  240 . Specifically, the plunger  210  is disposed within the hollow interior region defined within the cylinder  240 . The plunger  210  is inserted in the cylinder  240  such that the sealing end  232  of the plunger  210  is urged toward the end wall  292  of the cylinder  240 . Additional seals, described herein, are utilized between the plunger  210  and the cylinder  240 . 
   As shown in  FIGS. 6 and 7 , the dual action pump  5  of the present invention comprises two seals referred to herein as a primary seal  300  and a secondary seal  320 . The primary and secondary seals,  300  and  320  respectively, function in conjunction with the one-way valves  255 ,  267 , and  286 , to form two pumping chambers designated herein as Chamber A and Chamber B. Chamber A is generally defined as the interior cylindrical region below the primary seal  300  and Chamber B is generally defined as the interior annular region between the primary seal  300  and the secondary seal  320  and between the exterior surface of the plunger  210  and the interior surface  290  of the cylinder  240 . Before further describing Chambers A and B, it is instructive to consider the primary and secondary seals  300  and  320 . 
   The primary seal  300  is preferably provided by an O-ring  302  disposed within the annular recess  234  defined along the sealing end  232  of the plunger  210 . The O-ring  302  is disposed within the annular region between the sealing end  232  of the plunger  210  and the interior circumferential surface  290  of the pump cylinder  240 . As will be appreciated, as the plunger  210  is moved relative to the pump cylinder  240 , as described in greater detail herein, the primary seal  300  and specifically, the O-ring  302 , provides an air-tight seal between Chamber A below the seal  300  and Chamber B above the seal  300 . As the plunger  210  is moved along the length of the pump cylinder  240 , the O-ring  302  is carried along with the sealing end  232  of the plunger while maintaining sealing contact with the interior circumferential surface  290  of the pump cylinder  240 . The primary seal  300  is a two-way seal, and so prevents airflow past the seal  300  in either direction. It will also be appreciated that the primary seal  300  moves along the length of the cylinder  240  as the plunger  210  is displaced or moved therein. That is, the primary seal  300  is not stationary or fixed relative to the cylinder  240 . 
   Although the embodiments described herein refer to an O-ring such as O-ring  302  for certain seals, it will be appreciated that other types of seals may be utilized. For example, a seal having a non-circular cross-section may be used. Of these, representative examples include, but are not limited to, loaded lip seals and U-cup type seals. 
   The secondary seal  320  is preferably provided by one or more seals, such as an assembly of sealing members, that extend within the annular region between the exterior of the plunger  210  and the interior circumferential surface  290  of the pump cylinder  240 . The secondary seal  320  is preferably a one-way valve which only allows air flow within the annular region defined between the exterior surface of the plunger  210  and the circumferential interior surface  290  of the cylinder  240 , in a direction from the sealing end  232  of the plunger  210  toward the intake  248  defined in the cylinder  240 . It will also be appreciated that the secondary seal  320  is stationary or fixed relative to the cylinder  240 . That is, the secondary seal  320  is not moved along the length of the cylinder  240  as the plunger  210  is displaced. 
   The preferred dual action pump  5  according to the present invention also includes additional sealing members such as an inner annular seal  330 . Preferably, the seal  330  is in the form of one or more O-rings. The inner annular seal  330  is disposed at the head end of the cylinder  240 . The inner annular seal  330  is generally seated around the perimeter of the plunger  210  and extends between the outer surface of the plunger  210  and the circumferential interior surface  290  of the cylinder  240 . The inner annular seal  330  prevents passage of air between the regions above and below the seal  330 . As the plunger  210  is moved relative to the cylinder  240 , the inner annular seal  330  generally maintains its position at the head end of the cylinder  240 . 
   The primary seal  300 , the secondary seal  320 , and the inner seal  330 , in addition to performing the noted sealing functions, also serve to maintain alignment of the plunger  210  with respect to the pump cylinder  240 . That is, the seals  300 ,  320 , and  330  promote alignment between the plunger  210  and the cylinder  240 , and preferably, ensure that the longitudinal axis of the plunger  210  is not only parallel with the longitudinal axis of the cylinder  240 , but also that these two axes are co-linear with each other. Furthermore, the seals  300 ,  320 ,  330  not only promote the noted alignment between the plunger  210  and the cylinder  240 , but also ensure that this alignment is maintained during movement of the plunger  210  relative to the cylinder  240 . 
   In a preferred embodiment of the pump, a spring (not shown) is provided within the pump to urge the plunger  210  up and away from the nozzle end  270  of the cylinder  240 . The plunger may optionally contain a pressure-indicating device (not shown), such as a ball or slide, and pressure indication lines, and/or a pressure relief mechanism to reduce the pressure of the ball. 
   Referring further to  FIG. 6 , generally, the operation of the preferred dual action pump  5  is as follows. When the plunger  210  is pulled up or out (reverse stroke) from the cylinder  240 , the Chamber A increases in volume, thereby causing an initial decrease in pressure therein. Air then flows into the hollow passage defined in the plunger  210 , past the one-way valve  286 , and into Chamber A. Air within Chamber A is restricted from entry into annular-shaped Chamber B due to the primary seal  300 . Concurrently with the increase in volume of Chamber A during a reverse stroke of the plunger  210 , Chamber B undergoes a decrease in volume. This decrease in volume results in an increase in pressure of air within Chamber B and thus causes air to flow past the one-way valve  320  toward the intake  248  defined along the circumferential interior surface  290  of the cylinder  240 . It will be appreciated that air is restricted from flowing out of Chamber B past the seal  330 . Air is also prevented from flowing out of Chamber B via passage  260  by the one-way valve  267 . The valve  267  only permits air flow into chamber B, and not out of Chamber B. Air then enters the intake  248  and flows into the sidewall passage  252 , and eventually past the one-way valve  255  at the sidewall exit aperture  254 . The exiting air flows into the interior of the sport ball. 
   Referring to  FIG. 7 , when the plunger  210  is pushed in or down (forward stroke) with respect to the cylinder  240 , the volume in Chamber A decreases, thereby causing a pressure increase therein. Air within Chamber A cannot flow past the primary seal  300  nor the one-way valve  286 , and so, is urged out of the cylinder through the nozzle end  270  and into the interior of the sport ball. Concurrently with the volume in Chamber A decreasing, the volume in Chamber B is increasing. Accordingly, the pressure of air within Chamber B decreases. Air is drawn into inlet  262  through the passage  260  past the one-way valve  267  and into chamber B. The seal  320  prevents passage of air into Chamber B from the region above seal  320 . 
   This process is repeated until the desired amount of air has been added to the ball. With each stroke, both in and out, air is forced into the ball. 
   Unlike a typical single action pump where the seal between plunger and cylinder only forms a seal in one direction, the primary seal  300  of the preferred dual action pump  5  seals the Chambers A and B in both stroke directions. This allows the air in Chamber A to be forced into the ball during the down or forward stroke while preventing the air from escaping. The seal provided by seal  300  also allows the air that is drawn into Chamber B to be forced into the passage  252  and then into the ball during the up or reverse stroke while the Chamber A refills with air through the inlet in the plunger  210 . 
   As best shown in  FIGS. 4 and 9 , preferably, disposed near the distal end of the plunger  210  are two outwardly extending flanges  224  and  226  that cooperate with a cylinder collar  350  to hold the plunger  210  within the sidewall  246  of the cylinder  240 , and to release the plunger  210  for pumping. The cylinder collar  350  is also depicted in  FIG. 8 . The cylinder collar  350  is secured to the distal end of the cylinder  240 . The plunger  210  extends through the center of the cylinder collar  350 . The collar  350  is preferably cemented into the cylinder  240  using a suitable adhesive, such as a UV cured adhesive.  FIG. 8  shows an isometric view of the bottom of the cylinder collar  350  and illustrates open areas  352  on opposite sides of the central opening through which the two flanges  224  and  226  of the plunger  210  can pass in an unlocked position. In a locked position, the plunger  210  is pushed down and rotated such that the two flanges  224  and  226  pass under projections  354  and are rotated into locking recesses  356 .  FIG. 9  also illustrates that the cylinder  240  is retained within the ball by engagement between the flange  244  of the cylinder  240  and the groove  24  defined within the boot  20 . 
   As shown in  FIGS. 4 and 9 , attached to the upper end of the plunger  210  is the cap  212  that is designed to essentially completely fill the hole or aperture in the carcass. In some embodiments, such as a basketball or football, the button or cap  212  is preferably flush or essentially flush with the surface of the ball. In other embodiments, such as a soccer ball, the button or cap  212  is preferably positioned below the surface of the ball. This button  212  may be of any desired material. Examples of materials suitable for use as the button or cap  212  include urethane rubber, butyl rubber, natural rubber or any other material known in the art. A preferred rubber for use as the button or cap is a thermoplastic vulcanizate such as SANTOPRENE™ rubber, available from Advanced Elastomer Systems, Akron, Ohio. The button or cap should match the texture or feel of the outer surface of the ball. The surface of the button or cap may be textured to increase gripping characteristics if desired, such as for a basketball. For a soccer ball, the surface may be smooth. 
   In a preferred embodiment, fibers or other reinforcing materials for the cap may be incorporated into the rubber compound or thermoplastic material during mixing. Examples of fibers materials suitable for use include, but are not limited to, polyester, polyamide, polypropylene, Kevlar, cellulistic, glass and combinations thereof. Incorporation of fibers or other reinforcing materials into the button or cap improves the durability of the button and improves the union of the button or cap and the piston rod, thus preventing the button or cap from shearing off during use. Although the pump would still function without the button, it becomes very difficult to use. 
   Preferably, the button or cap  212  is co-injected with the plunger  210  as one part. Alternatively, the button or cap  212  may be co-injected with a connecting piece, and the button or cap  212  and connecting piece may then be attached to the upper end of the plunger  210  using an adhesive suitable for bonding the two pieces together. Co-injecting the button  212  and the plunger  210  as one part, or alternatively, the button  212  and the connecting piece as one part that is mounted to the plunger  210 , provides a more durable part that is less likely to break or come apart during routine use of the ball. The button or cap material and the plunger material need to be selected such that the two materials will adhere when co-injected. Testing of various combinations has shown that co-injecting or extruding a soft rubber button, such as a button comprising SANTOPRENE™, and a harder plunger, such as polycarbonate or polypropylene and the like, provides a durable bond without the need for adhesives. 
   The plunger  210  and the connecting piece may be formed of any suitable material, such as, but not limited to, polycarbonate (PC), polystyrene (PS), acrylic (PMMA), acrylonitrile-styrene acrylate (ASA), polyethylene terephthalate (PET), acrylonitrile-butadiene styrene (ABS) copolymer, ABS;/PC blends, polypropylene (preferably high impact polypropylene), polyphenylene oxide, nylon, combinations thereof, or any suitable material known in the art. Materials with high impact strength are preferred. The material used for the plunger is preferably clear or transparent, especially if a pressure-indicating device is used so that the user can view it. 
   Referring further to  FIG. 9 , mounted on the upper surface of the cylinder collar  350  is a pad  360  that is engaged by the cap  212  when the plunger  210  is pushed down to lock or unlock the plunger  210 . The pad  360  provides cushioning to the pump. The outer face  214  of the cap  212  may be textured or smooth to match the feel of the ball, as desired. Additionally, as shown in  FIG. 9 , the outer face  214  can define a slot  216  to assist or promote rotation of the plunger  210 . For basketballs, it is preferable that the top of the cap is textured, while for other sport balls, such as soccer balls and footballs, the top of the cap is preferably smooth. 
     FIGS. 5–7  of the drawings show the nozzle end  270  of the pump  5 .  FIG. 10  is a detailed cross section of that component. Shown in  FIG. 10  is one preferred embodiment of a one-way valve assembly of the duckbill-type that is disposed in the nozzle  270 . This assembly comprises an inlet end piece  269 , an outlet end piece  271  and an elastomeric duckbill valve  370  captured between the two end pieces. The end pieces  269  and  271  are preferably plastic, such as a polycarbonate, polypropylene, nylon, polyethylene, or combinations thereof, but may be any material suitable for use. The end pieces may be ultrasonically welded together. Although any desired one-way valve can be used on the exit nozzle  270  and although duckbill valves are a common type of one-way valves, a specific duckbill configuration is shown in  FIG. 11 . The duckbill valve  370  is preferably formed of an elastomeric silicone material and is molded with a cylindrical barrel  372  having a flange  374 . Inside of the barrel  372  is the duckbill  376  which has an upper inlet end  378  molded around the inside circumference into the barrel  372 . The walls or sides  380  of the duckbill  376  taper down to form the straight-line lower end with a duckbill slit  382 . The duckbill functions wherein inlet air pressure forces the duckbill slit  382  open to admit air while the air pressure inside of the ball squeezes the duckbill slit closed to prevent the leakage of air. Such a duckbill structure is commercially available from Vernay Laboratories, Inc. of Yellow Springs, Ohio. Any type of one-way valve or other valve capable of sealing known in the art may be used, as long as it prevents air from flowing out of the interior of the ball when not desired. 
   A pump assembly of the type described and illustrated herein is preferably made primarily from plastics such as polystyrene, polyethylene, nylon, polycarbonate and combinations thereof, but it can be made of any appropriate material known in the art. Although the assembly is small and light weight, perhaps only about 5 to about 25 grams, a weight may optionally be added to the ball structure to counterbalance the weight of the pump mechanism. In such an application, the weight, i.e. the counterweight, is positioned on or within the ball, and has a suitable mass, such that the resulting center of mass of the ball coincides with the geometric center of the ball. In lighter weight or smaller balls, such as a soccer ball, the pump assembly may weigh less and/or be smaller (shorter) than a corresponding pump assembly for a heavier ball, such as a basketball.  FIG. 12  illustrates such a counterbalance arrangement wherein a pump mechanism generally designated as  405  is on one side of a ball  400  and a standard needle valve  410  is on the opposite side of the ball  400 . In this case, the material  412  forming the needle valve  410  is weighted. Additional material can be added to the needle valve housing or the region surrounding the valve. Alternatively, a dense metal powder such as tungsten could be added to the rubber compound. The use of another pump or inflation valve is referred to herein as a secondary pump or secondary inflation valve. The additional pump is preferably an integral dual action pump as described herein. 
   The description thus far and the referenced drawings disclose a particular and preferred pump configuration. However, other pump arrangements can be used within the scope of the invention, as long as they utilize at least two chambers to provide for dual action. Examples of other pump arrangements that may be used with the invention are shown in co-pending application Ser. No. 09/594,980, filed Jun. 15, 2000; Ser. No. 09/594,547, filed Jun. 14, 2000; Ser. No. 09/594,180, filed Jun. 14, 2000; and Ser. No. 09/560,768, filed Apr. 28, 2000, incorporated herein by reference. Additional details and features that may be implemented in conjunction with the balls and pumps described herein are provided in U.S. Application publication No. US 2002/0187866, filed as Ser. No. 10/183,337 on Jun. 25, 2002; U.S. Pat. No. 6,491,595, filed as Ser. No. 09/712,116 on Nov. 14, 2000; and U.S. Pat. No. 6,287,225 filed as Ser. No. 09/478,225 on Jan. 6, 2000, all of which are hereby incorporated by reference. 
   Since the pressure in a sport ball can be too high through overinflation or a temperature increase, or too low through underinflation or air loss, it can be beneficial to have a pressure relief device and/or a pressure-indicating device that is integral to the pump. If the pressure is too low, additional air may be added using the self-contained pump of the invention. If the pressure is too high, the pressure may be relieved by bleeding pressure from the ball with the conventional inflating needle or other implement that will open the conventional inflation valve to release air. Alternatively, the pump may have a mechanism that allows the pressure to be relieved, either through action of the pump, or through the use of a relief mechanism built into the pump, such as a mechanism to open the one-way valve if desired to allow air to flow out of the interior of the ball. The pressure-indicating device of the present invention may then be used to determine if the ball is correctly inflated. If too much air is removed, additional air may be added using the pump. 
   The foregoing description is, at present, considered to be the preferred embodiments of the present invention. However, it is contemplated that various changes and modifications apparent to those skilled in the art may be made without departing from the present invention. Therefore, the foregoing description is intended to cover all such changes and modifications encompassed within the spirit and scope of the present invention, including all equivalent aspects.