Abstract:
A compressed air firing shell for a toy gun includes a firing chamber for receiving a soft projectile and a pressure chamber to store a high-pressure charge of air. A release port delimits the pressure chamber from the firing chamber. A piston within the pressure chamber seals the release port and unseals the release port upon triggered activation of the activation member to allow the charge to pass from the pressure chamber to the firing chamber to effect firing of the soft projectile.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to toy guns capable of shooting soft projectiles upon the release of stored compressed air. The invention more particularly, although not exclusively, relates to firing shells which can store a charge of compressed air for use, or integrated with such toy guns. 
     Toy guns capable of firing soft projectiles upon release of compressed air are known. These comprise pump-action or other mechanisms for forcing a jet of air against a projectile to cause it to be fired from the toy gun. The various known firing mechanisms are complex and costly to manufacture and can be unreliable in use. Furthermore, rapid-firing toy machine guns cannot generally exploit compressed air firing due to complexities associated with recharging a store of compressed air. 
     A compressed air firing shell for a toy gun overcomes or substantially ameliorates at least one of the above disadvantages and/or more generally provides an improved means of storing and releasing a charge of compressed air to fire soft projectiles from toy guns. 
     SUMMARY 
     There is disclosed herein a compressed air firing shell for a toy gun, comprising: 
     a firing chamber for receiving a soft projectile; 
     a pressure chamber adapted to store a high-pressure charge of air therein; 
     a release port from the pressure chamber to the firing chamber; 
     an activation member; and 
     a piston within the pressure chamber and sealing the release port and adapted upon triggered activation of the activation member to unseal the release port thereby allowing the charge to pass from the pressure chamber to the firing chamber to effect firing of the soft projectile therefrom. 
     Preferably, the firing shell further comprises an inlet valve via which pressurised air can enter the pressure chamber to provide said charge of air. 
     Preferably, said inlet valve is incorporated into the activation member. 
     Preferably, the activation member comprises a pin biased by a spring into a sealed position, the pin adapted to move against the spring and away from the sealed position upon application of external air pressure thereto to enable charging of the pressure chamber. 
     Preferably, the activation member comprises a cylindrical housing within which the spring is located, the piston sliding upon the cylindrical housing. 
     Alternatively, the piston can slide upon an inner surface of the pressure chamber. 
     Preferably, the firing shell further comprises protection means for preventing the firing of items other than a soft projectile having an elongate cavity from the firing chamber. 
     Preferably, the firing shell further comprises an elongate firing tube extending into the firing chamber and through which air passes from the release port, the elongate tube adapted to fit within an elongate cavity of the soft projectile. 
     Preferably, the elongate firing tube comprises a bleeder opening nearby the release port, and protection means comprise a sliding disc surrounding the elongate firing tube and movable between a first use position whereat air exiting the bleeder opening enters the elongate cavity of the soft projectile causing it to be fired, and a second non-use position whereat air exiting the bleeder opening is trapped behind the sliding disc. 
     Preferably, the firing shell further comprises a light spring biasing the sliding disc into the second position, the sliding disc adapted to compress the light spring upon interaction with the soft projectile. 
     Alternatively, the protection means comprises vents in the firing chamber adapted to surround the soft projectile. 
     Alternatively, the protection means comprises a base cylinder adjacent to the release port and adapted to surround a portion of the soft projectile. 
     There is further disclosed herein a charging mechanism when used with the above-disclosed firing shell, the charging mechanism comprising a charging cylinder containing a volume of air, the charging cylinder comprising a seal for sealing the volume of air against the exterior of the firing shell, reduction of said volume upon interaction with the firing shell pressurising the volume to thereby open the inlet valve so that air from the volume enters the pressure chamber to charge the pressure chamber. 
     Preferably, the volume is adapted to at least partially receive the firing shell to cause said reduction in volume. 
     Preferably, the seal is adapted to allow air to flow into the volume upon extraction of the firing shell from the volume. 
     The charging mechanism can further comprise a check valve adapted to allow air to flow into the volume upon extraction of the firing shell from the volume. 
     The charging mechanism can further comprise a base upon which the charging cylinder is mounted, a lever mounted to the base and adapted to bear down upon the firing shell for insertion thereof into the volume. 
     Alternatively, the charging mechanism can comprise a charging piston adapted to slide into the charging cylinder to cause said volume reduction. 
     There is further disclosed herein a toy gun incorporating the above-disclosed firing shell. 
     Preferably, the toy gun comprises a trigger-activated firing pin adapted to strike the activation member to effect said triggered firing activation. 
     Preferably, the firing shell is formed integrally with the toy gun. 
     Alternatively, the toy gun is adapted to receive the firing shell in removable fashion. 
     There is further disclosed herein a toy gun adapted to receive, or having integrally formed therein a multitude of the above-disclosed firing shells. 
     The toy gun might comprise an integral charging cylinder from which pressurised air is charged into each firing shell. 
     The toy gun might further comprise an advancing mechanism for aligning each charging shell with the charging cylinder. 
     There is further disclosed herein a toy bullet chain comprising a plurality of articulated links, at least one of the links housing the above-disclosed firing shell. 
     There is further disclosed herein a combination of the above toy bullet chain and the above-disclosed charging mechanism, the charging mechanism comprising a cradle configured to support a link of the chain as the charging piston slides into the charging cylinder. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: 
         FIG. 1  is a schematic cross-sectional elevation of a firing shell with a soft projectile loaded therein prior to pressure-charging of the pressure chamber; 
         FIG. 2  is a schematic cross-sectional elevation of the firing shell and soft projectile with the pressure chamber charged; 
         FIG. 3  is a schematic cross-sectional elevation of the charged firing shell and soft projectile just about to be fired; 
         FIG. 4  is a schematic cross-sectional elevation of the firing shell with the soft projectile being fired; 
         FIG. 5  is a schematic cross-sectional elevation of a portion of a pressure-charging device with the firing shell being withdrawn therefrom; 
         FIGS. 6 ,  7  and  8  are schematic cross-sectional elevations of a firing shell being loaded into a pressure-charging device; 
         FIG. 9  is a schematic cross-sectional elevation of a charged firing shell withdrawn from the pressure-charging device; 
         FIG. 10  is a schematic cross-sectional elevation of a firing shell about to be inserted into a pressure-charging device; 
         FIG. 11  is a schematic cross-sectional elevation of a pressure-charging device having a lever for providing a mechanical advantage to the user; 
         FIG. 12  is a schematic cross-sectional elevation showing the firing shell being withdrawn from the pressure-charging device; 
         FIG. 13  is a schematic cross-sectional elevation of a charged firing shell withdrawn from the pressure-charging device; 
         FIGS. 14 and 15  fundamentally repeat  FIGS. 3 and 4  for convenience; 
         FIG. 16  is a schematic cross-sectional elevation of a toy gun incorporating a loaded firing shell prior to firing; 
         FIG. 17  is a schematic cross-sectional elevation of the toy gun and firing shell with a soft projectile being fired therefrom; 
         FIGS. 18 and 19  show pre- and post-firing configurations of a firing shell and soft projectile, the firing shell having no protection means against firing of incorrect and potentially dangerous substitute projectiles; 
         FIGS. 20 and 21  show pre- and post-firing configurations of a firing shell and soft projectile, the firing shell having a sliding protection disc for preventing the firing of incorrect projectiles; 
         FIGS. 22 and 23  show pre- and post-firing configurations of a firing shell and soft projectile, the firing shell having a base cylinder in the firing chamber and air vents to prevent firing of incorrect projectiles therefrom; 
         FIGS. 24 and 25  show pre- and post-firing configurations of a similar firing shell to that shown in  FIGS. 22 and 23  together with a soft projectile, the firing shell in this embodiment having no elongate firing tube; 
         FIGS. 26 and 27  are schematic cross-sectional elevations of a firing shell having an inlet valve formed separately to the activation member before and during priming respectively; 
         FIGS. 28 and 29  are schematic cross-sectional elevations of the firing shell having a different separately formed inlet valve before and during priming respectively; 
         FIGS. 30 to 33  are schematic cross-sectional elevations of a firing shell having an alternative piston configurations at various stages of operation; 
         FIG. 34  is a schematic elevation of a toy gun adapted to fire a multitude of soft projectiles from a plurality of firing shells; 
         FIGS. 35 and 36  are schematic cross-sectional elevations of a toy gun of  FIG. 34  at different stages of operation; 
         FIG. 37 . is a schematic elevation of a toy bullet chain having charging shells loaded within each link of the chain and a stand-alone charging cylinder being used to charge one of the shells; and 
         FIG. 38  is a schematic elevation of a stand-alone charging station incorporating the charging cylinder shown in  FIG. 37 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In  FIGS. 1 to 3  of the accompanying drawings there is depicted schematically a firing shell  10  which would typically be formed of moulded plastics material. The shell is substantially cylindrical and has at its forward end a firing chamber  18  into which a soft projectile  16  is partially received. At the back of the shell  10 , there is provided a pressure chamber  12  which receives a charge of compressed air which upon release by the user causes the soft projectile  16  to be ejected from the firing chamber  18 . A release port  14  from the pressure chamber  12  communicates with an elongate firing tube  15  which extends into an elongate cavity  17  provided within the soft projectile. 
     At the back of the pressure chamber  12 , there is an activation member  11  which comprises a pin  22  located within a cylindrical housing  21 . The pin  22  is biased to the left by a captured coil spring  23  which surrounds it. At the right end of the cylindrical housing  21 , the pin  22  passes through an aperture which is slightly larger than its own diameter. Air can pass around the pin through this aperture. However, spring force applied by spring  23  causes the pinhead (not numbered) at the right-most end of the pin to seal against the aperture. At the left-most end of the pin  22 , there is another pinhead (again not numbered) which slides freely within the cylindrical housing  21  and air can pass around it. 
     Surrounding and sliding upon the outer surface of the cylindrical housing  21  is a piston  13 . The flat right hand surface of the piston  13  can bear against the release port  14  to seal the pressure chamber  12 . A small O-ring can be provided around the release port to maintain a good seal with the piston  13 . 
     In order to charge the pressure chamber  12  with compressed air, it is necessary to increase air pressure behind (to the left of) the valve  11 . When the pressure differential across the valve  11  is sufficient to overcome the force of spring  23 , the pin  22  will move to the right and air will flow past it into the pressure chamber  12 . When the pressure differential has equalised with the spring force, the valve  11  will seal. Air can leak around the outer surface of the cylinder  21  from within the piston  13  to pressurise the pressure chamber  12 . Increased pressure within the chamber  12  forces the piston  13  to seal against the release port  14 . 
     When a firing force F is applied to the left end of the pin  22 , the right pinhead will lift from the aperture around the pin at the right end of the cylinder  21  and pressurised air within the piston  13  will escape to atmosphere past the pin toward the left. This rapid reduction of pressure within the piston  13  results in a pressure differential across its flat (right) face causing the piston to move to the left and break the seal at the release port  14 . As a result, the charge of compressed air within the pressure chamber  12  escapes rapidly through the release port  14  and into the elongate firing tube  15  to cause the projectile  16  to fire from the shell  10 . 
     The pressure chamber  12  can be charged by pushing the firing shell  10  into a charging cylinder  24 . Such a charging cylinder is shown in  FIGS. 5 to 11 . As mentioned above, it is only necessary to increase air pressure behind the activation member  11  sufficiently to overcome the force of spring  23  to effect charging of the pressure chamber  12 . A typical charging cylinder  24  has a ring cap  30  which locates a seal  31 . Seal  31  bears against the outside surface of the firing shell  10  as the firing shell takes up a volume  32  within the charging cylinder  24 . Some mechanical advantage might be desirable and to this end, a jig is shown in  FIG. 11 . This jig includes a base  33  upon which the charging cylinder  24  is mounted. A lever  34  is also mounted upon the base  33 . A cup  35  attached to the lever  34  bears down upon the firing shell  10  so as to force it into the charging cylinder to take up the volume Air within the volume  32  compresses and passes the activation member  11  to charge the pressure chamber  12 . In order to release the charged firing shell  10  from the charging cylinder the seal  31  may be tapered as depicted in  FIG. 5  so that air can enter the volume  32  as indicated by arrows A. Alternatively, a one-way check valve  36  can be provided in the bottom of the charging cylinder  24  so that replenishing air can enter the volume  32  upon withdrawal of the charged firing shell  10 . 
     The firing shell  10  is intended to fire safe soft projectiles  16 . In order to prevent children from firing other dangerous objects such as pen caps, marbles, pencils and batteries for example various protection means are provided. Examples of these are illustrated in  FIGS. 20 to 25 .  FIGS. 18 and 19  show an embodiment incorporating no protection means and are included alongside these figures for comparative illustration purposes only. 
     In  FIGS. 20 and 21 , the protection means comprises a sliding disc  19  located just forward of the release port  14 . The sliding disc  19  is biased to the right by a light spring  20  to bear against a step  25  which is formed on the inside cylindrical surface of the firing shell  10 . The sliding disc  19  surrounds the elongate tube  15 . There is a lateral bleeder hole  26  through the elongate tube  15  via which air within the elongate tube  15  can escape. This bleeder hole  26  is located behind the sliding disc  19  in the rest position. If a pen cap for example were inserted over the elongate tube  15  into the firing shell  10 , the sliding disc  19  would remain in position so that a released charge of air from the pressure chamber  12  would escape behind the sliding disc  19  and be captured by it, rather than ejecting the pen cap in dangerous fashion. When the correct soft projectile is inserted over the elongate tube  15 , it will push the sliding disc  19  to the left against the light spring  20  and slight frictional engagement between the elongate tube  15  and the internal surface of the elongate cavity  17  will retain the projectile in position until firing. Now when the charge of compressed air is released, it will pass through the bleeder hole of the elongate tube  15  to fire the soft projectile. 
     An alternative embodiment is depicted in  FIGS. 22 and 23 . In this embodiment, a short base cylinder  28  is provided around the bleeder hole  26 . Again, if a pen cap or other dangerous object were to be inserted, the base cylinder  28  would prevent it from covering the bleeder hole  26 . Even if say a pencil were received closely within the opening of the firing shell  10 , vent holes  27  would cause the released charge of air to escape therethrough, rather than firing the pencil. If a proper soft projectile as depicted in the drawings is inserted however, its tail end would be received within the short base cylinder  28  to cover the bleeder hole  26  and air would pass through the elongate cylinder via bleeder hole  26  to fill the space within base cylinder  28  to cause firing of the soft projectile. The vent holes  27  would not then impinge upon firing efficiency. 
     A similar embodiment is depicted in  FIGS. 24 and 25 . However, in this embodiment, no elongate tube  15  is provided. In this case, the short base cylinder  28  in combination with the vents  27  will be sufficient to prevent firing of the majority of dangerous objects likely to be found and used by children. 
     A simple toy gun  29  embodying the invention is depicted in  FIGS. 16 and 17 . A firing shell  10  could be inserted into the barrel  40 , or its features could be formed integrally with the toy gun  29 . The trigger  37  pulls against a spring  42  to release a firing lever  38 . A strong spring  41  pivots the firing lever  38  to the right so that the firing pin  39  impacts against the activation member  11 . This causes firing of the soft projectiles  16  as described above. 
     Although not depicted, a rapid-fire toy machine gun for example, could include a magazine loaded with a plurality of pre-charged firing shells  10 . Alternatively, a bullet chain loaded with pre-charged firing shells  10  could be machine-fed into a firing bay of a toy machine gun. 
     In the above examples, the activation member  11  also functions as an inlet valve via which the pressure chamber  12  is charged. However, separately formed inlet valves are also envisaged.  FIGS. 26 and 27  depict an example of this. 
     A resilient flap  43  surrounding the activation member  11  can cover one or more inlet apertures  44 . Upon increased external pressure, air is allowed to flow through the inlet apertures  44  as indicated by the arrow in  FIG. 27 . After the pressure chamber  12  is primed, the flap  43  will seal the inlet apertures. 
       FIGS. 28 and 29  show an alternative arrangement in which a separate inlet valve  43 ′ is provided. This can be in the form of a simple check valve for example. Again, pressurised air can enter the pressure chamber  12  via this check valve. In each of the embodiments of  FIGS. 26 to 29 , the spring provided in the activation member  11  would be sufficiently strong to maintain a seal at the activation member during priming. 
     In each of the above embodiments, the piston  13  is mounted upon the activation member  11 . An alternative, the piston might be adapted to slide upon the inner surface of the pressure chamber  12 . Such an example is shown in  FIGS. 30 to 33 . Whilst this example may not be as efficient as those previously described, it is nonetheless a viable alternative. 
     In this embodiment, a broader piston  13 ′ slides within the pressure chamber  12  and is adapted to bear and seal against a projecting release port  14 ′. This ensures that a volume of air remains to the right of the piston within the pressure chamber  12  at all times. The piston functions in exactly the same manner as does the piston  13  of the previous examples, but there is some loss of efficiency due to the increased surface area of the piston upon which the pressure differential across it takes effect. 
     As a further alternative, a toy gun could be provided with an inbuilt charging facility similar to charging cylinder  24  and activated upon pump action for example. 
     A toy gun  45  for firing a multitude of soft projectiles is depicted in  FIGS. 34 to 36 . A rotating barrel  40 ′ provides a multitude of firing shells  10 ′ in a circular array. The firing shells rotate about a longitudinal axis at the centre of the barrel  40 ′. Provided upon the body of a toy gun  45  is an integral charging cylinder  24 ′ having a priming handle  46  extending rearward therefrom. The shells  10 ′ come into alignment with the charging cylinder  24 ′ as the barrel  40 ′ is rotated during play. A player can reciprocate the priming handle  46  to charge each firing shell  10 ′ in turn between firing shots. Retraction of the priming handle  46  will fill the charging cylinder  24 ′ with air. Pushing forward on the priming handle  46  will charge air from the priming cylinder  24 ′ into the pressure chamber of each of the firing shells  10 ′. The priming handle  46  can be linked to a barrel-advancing mechanism so that the barrel  40 ′ will advance to the next firing shell after each priming action. Alternatively, the barrel  40 ′ could be adapted for manual hand-turning. This would enable all of the firing shells  10 ′ to be primed prior to firing of any one of the shells in play. Moreover, after all of the shells  10 ′ are charged, the player can pull the trigger to strike the activation member and fiery dart. If the trigger is linked to a barrel-advancing system, each activation of the trigger will shoot a dart. This can provide a rapid shooting response—working somewhat like a machine gun. 
     Rather than forming a charging mechanism integrally with a toy gun (single shot or multi-projectile), a further style of stand-alone charging mechanism is envisaged. An example is illustrated in  FIGS. 37 and 38  and this is designed for use with a bullet chain comprising a plurality of articulated links  47  which may be fed into a toy machine gun. 
     Each of the links  47  is configured to receive a firing shell  10 . Each firing shell  10  may be pre-loaded with projectiles  16 . 
     The charging cylinder  24 ′ is formed into a cradle  50  across which the chain can be draped with one link  47  supported by the cradle at a time. The cradle  50  might be supported by legs  49  to a base  33 ′ as shown in  FIG. 38 . 
     The cradle  50  houses a charging cylinder  24 ′. Rather than inserting the firing shells  10  into the charging cylinder, the shells press against a seal  48  at the left end of the charging cylinder  24 ′. A charging piston  46  slides into the charging cylinder  24 ′ to reduce its internal volume  32  as indicated by the dotted lines in  FIG. 37 . The compressed air passes through the inlet valve as described earlier. 
     The figures depict a cap ring  30  locating a seal  31  which seals against the external surface of the charging piston  46  to maintain pressure. The charging piston  46  may incorporate a check valve (not shown) to ease its extraction from the charging cylinder  24 ′. 
     The internal structure of the charging piston  46 , charging cylinder  24 ′ and seals  3  and  48  are typically the same as those incorporated into the toy gun of  FIGS. 34 to 36  in which some of these details are not shown.