Low velocity projectile marker

Abstract

A low pressure, low velocity projectile marker for youth shooting sports as an acceptable alternative to the traditional sport of paintball. The marker includes an onboard, hand activated pressure system to charge an air reservoir up to a maximum pressure of 150 psi (11 kg/cm 2 ) as limited by a pressure relief valve. A removable barrel/magazine assembly stores and visibly displays a plurality of projectiles. The barrel/magazine assembly is inserted and sealably locked into a pressure deliver conduit of the marker. A trigger mechanism operates a fire control valve to precisely release a controlled, momentary pulse of compressed air in order to discharge a single projectile through the barrel of the marker.

Having thus described our invention, we claim:  
     
         1 . A low velocity projectile marker for seriatim firing a quantity of projectiles having a uniform cross sectional outer diameter, said marker comprising: 
 a marker body frame;    a compressed air reservoir connected to said marker body frame for containing a supply of compressed air at a pressure less than about 150 psi (11 kg/cm 2 );    a self-contained air compressor mounted on said marker body frame and connected to said reservoir in order to charge said reservoir with a supply of compressed air;    a barrel connected to said frame body and having a cylindrical barrel bore substantially equal to the cross sectional outer diameter of projectiles to be fired;    a firing chamber connected to one end of said barrel and having a firing chamber bore slightly less than the cross sectional outer diameter of a projectile to be fired whereby a projectile engaging said firing chamber bore creates a pressure seal therewith;    a projectile storage magazine connected to said firing chamber for storing a quantity of projectiles to be fired and to deliver projectiles seriatim to said firing chamber; and    a trigger mechanism carried on said body frame and interconnecting said compressed air reservoir with said firing chamber, said trigger mechanism operable to deliver a momentary pulse of compressed air from said reservoir to said firing chamber in order to discharge a projectile from said firing chamber through said barrel.    
     
     
         2 . The marker as in  claim 1 , said air compressor comprising an air pump and a check valve interconnecting said air pump to said reservoir so as to admit air flow from said air pump to said reservoir and to block air flow from said reservoir back to said air pump.  
     
     
         3 . The marker as in  claim 2 , said air pump including a pressure relief valve to prevent said air pump from compressing air greater than 150 psi (11 kg/cm 2 ).  
     
     
         4 . The marker as in  claim 3 , said air pump including a piston fitted within a cylinder in order to compress air, a check valve interconnecting said cylinder to said reservoir, and a manually operable hand lever pivotally connected at one end thereof to said marker body frame for limited arcuate intake and compression strokes, and connected intermediate the ends thereof to said piston whereby intake and compression strokes of said hand lever translate to linear movement of said piston within said cylinder to deliver compressed air through said check valve to said reservoir.  
     
     
         5 . The marker as in  claim 4 , said hand lever pivotally connected at one end thereof to said marker body frame above said barrel to achieve mechanical leverage advantage for said compression stroke.  
     
     
         6 . The marker as in  claim 5  further including a sighting aperture through said body frame and said hand lever to provide a line of sight substantially parallel with and above the cylindrical bore of said barrel.  
     
     
         7 . The marker as in  claim 4 , said piston having a piston head moveably sealed against the interior wall of said cylinder and said pressure relief valve comprising a spring biased valve body mounted on said piston head with a spring received within said piston and biasing said valve body to a sealed position with respect to said piston head when compressed air within said cylinder is less than or equal to approximately 150 psi (11 kg/cm 2 ), and wherein compressed air within said cylinder greater than 150 psi (11 kg/cm 2 ) operates against said valve body and spring to unseal said valve body from said piston head to bleed compressed air from said cylinder rather than deliver excessive pressure to said reservoir.  
     
     
         8 . The marker as in  claim 4 , said hand lever including a manually depressible catch to lock said hand lever to said marker body frame to prevent pivot movement of said hand lever with respect to said marker body frame.  
     
     
         9 . The marker as in  claim 1 , said barrel extending from said firing chamber to an outer, muzzle end and having a plurality of opening extending through the barrel near the muzzle end thereof in order to permit the escape of compressed air in the event of blockage of the muzzle end.  
     
     
         10 . The marker as in  claim 1 , said firing chamber including a truncated spherical seat having a maximum diameter substantially equal to the uniform outer diameter of the projectiles to be fired and a minimum diameter less than the uniform outer diameter of the projectiles to be fired whereby a projectile engages said truncated spherical seat in a gas tight relationship.  
     
     
         11 . The marker as in  claim 10 , said minimum diameter of said truncated spherical seat being sized to permit a projectile to pass therethrough when a momentary pulse of compressed air is delivered to said firing chamber  
     
     
         12 . The marker as in  claim 10 , said minimum diameter of said truncated spherical seat being sized to equal approximately 80 to 90 percent of the uniform outer diameter of the projectiles to be fired.  
     
     
         13 . The marker as in  claim 1 , said projectile storage magazine comprising an elongate cylindrical tube having first and second ends and a diameter slightly larger than the projectiles to be fired for storage of a quantity of projectiles between said first and second ends, said first end being connected to said firing chamber for seriatim delivery of projectiles thereto.  
     
     
         14 . The marker as in  claim 13 , said projectile storage magazine including openings adjacent said firing chamber to deliver a momentary pulse of compressed air from said compressed air reservoir behind a projectile biased against said truncated spherical seat of said firing chamber in order to propel the projectile past said truncated spherical seat and into said barrel.  
     
     
         15 . The marker as in  claim 13 , said projectile storage magazine having a flexible retainer near said second end thereof to permit projectiles to be loaded into said magazine from said second end and to prevent projectiles within said magazine from falling out of said second end of said magazine.  
     
     
         16 . The marker as in  claim 13 , said projectile storage magazine including a substantially transparent window therein for visual determination of the number of projectiles in said magazine and firing chamber.  
     
     
         17 . The marker as in  claim 13 , said marker further including a projectile plunger mounted to said marker body frame and extended into said magazine tube, and a biasing spring associated with said plunger to urge any projectiles within said magazine tube to engagement with said firing chamber.  
     
     
         18 . The marker as in  claim 13 , said marker further including a cylindrical, pressure delivery conduit connected to said marker body frame and having an internal diameter larger than the outside diameter of said magazine tube; and a normally closed, fire control valve interconnecting said delivery conduit to said compressed air reservoir.  
     
     
         19 . The marker as in  claim 18 , said barrel, firing chamber and magazine tube being integrally formed as a removable assemblage whereby at least said firing chamber and magazine tube may be removably insertable into said pressure deliver conduit to form an annulus therewith, and including a first pressure seal adjacent said firing chamber and a second pressure seal adjacent said second end of said magazine tube whereby a momentary pulse of compressed air from said reservoir may be delivered to said conduit to travel through said annulus formed by said deliver conduit and said magazine tube, through said openings in the first end of said magazine tube to said firing chamber in order to propel the projectile past said truncated spherical seat and into said barrel.  
     
     
         20 . The marker as in  claim 19 , said assemblage and said pressure deliver conduit including substantially transparent windows therein for visual determination of the number of projectiles in said magazine and firing chamber.  
     
     
         21 . The marker as in  claim 19 , said delivery conduit further including a twist lock connection between said deliver conduit and said removable assemblage to prevent said assemblage from being propelled from said marker body frame.  
     
     
         22 . The marker as in  claim 21 , said deliver conduit including a safety port therethrough between said first and second pressure seals in order to vent compressed air in the event the twist lock connection between said deliver conduit and said removable assemblage is not in a locked position to prevent said assemblage from being propelled from said marker body frame, and said magazine tube including a seal pad to register with and seal said safety port of said deliver conduit when said deliver conduit and said removable assemblage are locked in position to prevent said assemblage from being propelled from said marker body frame.  
     
     
         23 . The marker as in  claim 1 , said trigger mechanism including a manually depressible trigger and fire control valve interconnecting said compressed air reservoir with said firing chamber and being spring biased to a normally closed position to prevent compressed air flow from said reservoir to said firing chamber, whereby fully depressing said trigger trips said fire control valve to momentarily open and causes a brief pulse of compressed air to flow from said reservoir, through said fire control valve to said firing chamber in order to discharge a projectile from said firing chamber through said barrel.  
     
     
         24 . The marker as in  claim 18 , said trigger mechanism further including a spring biased rotatable cam wheel connectively interposed between said depressible trigger and said fire control valve, whereby said trigger engages said cam wheel upon being depressed and rotates said cam wheel against its spring bias until said trigger fully depressed releases said cam wheel which rotates under influence of its spring force to impact a trip anvil associated with the fire control valve, whereby the impact of said trip anvil instantaneously opens the fire control valve against its spring bias to cause a brief pulse of compressed air to flow from said reservoir, through said fire control valve to said firing chamber in order to discharge a projectile from said firing chamber through said barrel.  
     
     
         25 . The removable barrel, firing chamber and magazine tube assemblage for a projectile firing marker having a marker body frame; a compressed air reservoir connected to said marker body frame for containing a supply of compressed air at a pressure less than about 150 psi (11 kg/cm 2 ); a self-contained air compressor mounted on said marker body frame and connected to said reservoir in order to charge said reservoir with a supply of compressed air; a tubular pressure delivery conduit connected to said marker body frame; a normally closed, fire control valve interconnecting said delivery conduit to said compressed air reservoir; and a trigger mechanism carried on said body frame and operable to deliver a momentary pulse of compressed air from said reservoir to said pressure delivery conduit; said assemblage comprising: 
 a barrel having a cylindrical barrel bore substantially equal to the cross sectional outer diameter of a projectile to be fired;    a firing chamber connected to one end of said barrel and having a firing chamber bore slightly less than the cross sectional outer diameter of a projectile to be fired whereby a projectile engaging said firing chamber bore creates a pressure seal therewith; and    a tubular projectile storage magazine connected to said firing chamber for storing a quantity of projectiles to be fired, said magazine having an outside diameter less than the inside diameter of said tubular pressure delivery conduit to form an annulus therewith;    whereby a momentary pulse of compressed air from said reservoir released by said trigger mechanism travels through said annulus to said firing chamber in order to discharge a projectile from said firing chamber through said barrel.    
     
     
         26 . The assemblage as in  claim 25 , said projectile storage magazine comprising an elongate cylindrical tube having first and second ends and a diameter slightly larger than the projectiles to be fired for storage of a quantity of projectiles between said first and second ends, said first end being connected to said firing chamber for seriatim delivery of projectiles thereto.  
     
     
         27 . The assemblage as in  claim 26 , said projectile storage magazine including openings adjacent said firing chamber to deliver a momentary pulse of compressed air from said compressed air reservoir behind a projectile biased against said firing chamber bore in order to propel the projectile past said firing chamber bore and into said barrel.  
     
     
         28 . The assemblage as in  claim 26 , said projectile storage magazine having a flexible retainer near said second end thereof to permit projectiles to be loaded into said magazine from said second end and to prevent projectiles within said magazine from falling out of said second end of said magazine.  
     
     
         29 . The assemblage as in  claim 26 , said projectile storage magazine including a substantially transparent window therein for visual determination of the number of projectiles in said magazine and firing chamber.  
     
     
         30 . The assemblage as in  claim 27  being integrally formed as a removable assemblage whereby at least said firing chamber and magazine tube may be removably insertable into said pressure deliver conduit to form said annulus, and including a first pressure seal adjacent said firing chamber and a second pressure seal adjacent said second end of said magazine tube whereby a momentary pulse of compressed air from said reservoir may be delivered to said conduit to travel through said annulus formed by said deliver conduit and said magazine tube, through said openings in the first end of said magazine tube to said firing chamber in order to propel the projectile past said firing chamber and into said barrel.  
     
     
         31 . The assemblage as in  claim 30 , said delivery conduit further including a twist lock connection between said deliver conduit and said removable assemblage to prevent said assemblage from being propelled from said marker body frame.  
     
     
         32 . The assemblage as in  claim 31 , said deliver conduit including a safety port therethrough between said first and second pressure seals in order to vent compressed air in the event the twist lock connection between said deliver conduit and said removable assemblage is not in a locked position to prevent said assemblage from being propelled from said marker body frame, and said magazine tube including a seal pad to register with and seal said safety port of said deliver conduit when said deliver conduit and said removable assemblage are locked in position to prevent said assemblage from being propelled from said marker body frame.