Efficient high-velocity compressed gas-powered gun

Abstract

A lower receiver has a trigger assembly. An upper receiver is coupled to the lower receiver. The lower receiver has a bolt assembly and an L-shaped slot. The L-shaped slot has a long leg, a junction, and a short leg. The bolt assembly interacts with the L-shaped slot. The upper receiver has a rear end to which a compressed gas power source can be coupled. The upper receiver has a gas path from the compressed gas power source for firing a projectile through a barrel and for cocking the bolt assembly. The gas path is entirely contained by the upper receiver.

What is claimed is: 
     
         1 . An apparatus comprising:
 a lower receiver means having a trigger assembly means;   an upper receiver means, coupled to the lower receiver means, having a bolt assembly means and an L-shaped slot means, wherein the L-shaped slot means has a long leg, a junction, and a short leg, and wherein the bolt assembly interacts with the L-shaped slot means;   the upper receiver means having a rear end means for coupling with a compressed gas power source means; and   a gas path means, coupled to the compressed gas power source means, for firing a projectile through a barrel and for cocking the bolt assembly, wherein the gas path means is entirely contained within the upper receiver.   
     
     
         2 . The apparatus of  claim 1  wherein the gas path means comprises:
 a first segment means for providing a path for gas through the upper receiver past the bolt assembly means toward a front end of the upper receiver, wherein the front end and rear end are on opposite ends of the upper receiver means, 
 a second segment means, coupled to the first segment means, for providing a path for gas toward the rear end of the upper receiver to an input side of a valve means that is actuatable by the trigger assembly, and 
 a third segment means, coupled to an output side of the valve means, for providing a path for gas into a barrel coupled to the upper receiver and into the bolt assembly. 
 
     
     
         3 . The apparatus of  claim 2  wherein:
 the first segment means of the gas path means has:
 an air source adapter means, to which the compressed gas power source means can be coupled, the air source adapter having a boss to release gas from the compressed gas power source means coupled to the air source adapter and an outlet port through which the released gas can flow, and 
 a transfer tube means coupled to the outlet port of the air source adapter, the transfer tube means extending through the upper receiver means toward the front end of the upper receiver means. 
 
 
     
     
         4 . The apparatus of  claim 3  wherein:
 the second segment means of the gas path means has:
 a transfer block means for providing a path for gas from an inlet port coupled to the transfer tube, through a transfer groove around a transfer bushing, which is coupled to the barrel, and out an outlet port toward the rear end of the lower receiver; and 
 a connection from the outlet port of the transfer block to the input side of the valve. 
 
 
     
     
         5 . The apparatus of  claim 4  wherein the valve has:
 a valve body having an inside diameter, a striker-proximate end, and an inlet end; 
 a valve stem having a striker end protruding from the striker-proximate end of the valve body and having a mushroom-shaped element coupled adjacent an inlet end of the valve stem, a curved surface of the mushroom-shaped element facing the striker end of the valve stem; 
 a valve seal slidably coupled to the valve stem between the mushroom-shaped element and the striker end of the valve stem, wherein the valve seal seals against the inside diameter of the valve body; 
 a valve spring engaged with and urging the mushroom-shaped element against the valve seal; and 
 an outlet port through the valve body, wherein a path for gas through the valve from the inlet end to the outlet port is created when pressure is exerted on the striker end of the valve stem of sufficient force to overcome the force of the valve spring holding the mushroom-shaped element against the valve seal. 
 
     
     
         6 . The apparatus of  claim 1  wherein the trigger assembly means is select-fire striker based and fits within select-fire hammer based trigger constraints. 
     
     
         7 . The apparatus of  claim 1  wherein the trigger assembly means comprises:
 an intermediate striker having:
 a longitudinal body having a front end and a rear end; 
 a cocking cap screw projecting from and adjacent to the rear end of the longitudinal body, 
 a longitudinal spring guide orifice partially through the longitudinal body, 
 a main spring compression cavity coaxial with, and having a larger diameter than, the longitudinal spring guide orifice, and extending a main spring compression depth into the rear end of the longitudinal body, 
 a lock face in the longitudinal body, wherein the lock face faces the front end of the longitudinal body, is transverse to the longitudinal spring guide orifice, and is set back from the rear end of the longitudinal body; 
 
 a cylindrical spring guide inserted into the longitudinal spring guide orifice; 
 a helical main spring mounted on the spring guide and constrained on one end by an intermediate striker stop and contained on the other end by the main spring compression cavity; and 
 a striker positioned between the intermediate striker and a valve stem on the valve. 
 
     
     
         8 . The apparatus of  claim 7  wherein the trigger assembly means comprises:
 a trigger element having:
 a trigger body, 
 a trigger slot to engage a trigger pin coupled to the lower receiver about which the trigger element rotates, 
 a shelf-sear engagement arm extending from the trigger slot, 
 an adjustment screw extending from the shelf-sear engagement arm, and 
 an auto-sear-linkage engagement pin coupled to the trigger body frontward of the trigger slot; 
 
 a trigger spring engaged with the trigger body urging the trigger into a before-firing position; 
 a shelf sear having:
 an elongated body that rotates around an auto-sear-linkage pin coupled to the lower receiver, 
 a main-sear-supporting arm adjacent to a front end of the shelf sear elongated body, 
 an L-shaped element adjacent to a rear end of the shelf sear elongated body; 
 
 a shelf sear spring coupled to the front end of the shelf sear elongated body that urges the shelf sear to rotate about the auto-sear-linkage pin; 
 a main sear having:
 a main sear front end and a main sear rear end, 
 a hook-shaped cutout adjacent the main sear front end, 
 a slot engaged with a main sear pin coupled to the lower receiver, 
 a tab having:
 a rearward facing flat face that engages the lock face of the intermediate striker when the main sear is in a before-firing position, and 
 a forward facing ramped face, and 
 
 a main-sear shelf that engages the main-sear-supporting arm of the shelf sear when the main sear is in the before-firing position; 
 
 a main sear spring coupled adjacent to the main sear rear end that urges the main sear to move and rotate about the main sear pin as constrained by the slot in the main sear; 
 an auto sear having:
 a lower-case-h-shaped auto-sear body having a main body, a cross piece extending from the main body, and an end piece extending from the cross piece, 
 a shelf in an area between the main body and the cross piece, and 
 an auto-sear pin coupled to the end piece; 
 
 a trigger-to-auto-sear linkage coupled to and rotatable around the auto-sear-linkage pin, the trigger-to-auto-sear linkage having:
 a pusher arm extending from the auto-sear-linkage pin into an area between the main body and the end piece of the auto sear; 
 a pinned arm from the auto-sear-linkage pin at an obtuse angle from the pusher arm, the pinned arm having a trigger-to-auto-sear-linkage slot that engages with the auto-sear-linkage engagement pin; 
 
 wherein:
 moving the trigger body from a before-firing position to an after-firing position causes:
 the adjustment screw extending from the shelf-sear engagement arm to engage the shelf sear and cause the shelf sear to rotate about the auto-sear-linkage engagement pin so that the main-sear-supporting arm no longer supports the main sear, and 
 the trigger-to-auto-sear linkage to rotate around the auto-sear-linkage pin as constrained by the trigger-to-auto-sear-linkage slot such that the pusher arm of the trigger-to-auto-sear linkage pushes the auto sear from a before-firing position to an after-firing position; 
 
 as a result of the main-sear-supporting arm no longer supporting the main sear, the intermediate striker causes the main sear to rotate such that the tab on the main sear no longer engages the lock face of the intermediate striker, allowing the intermediate striker to move to cause the striker to engage the valve stem to open the valve; 
 after the intermediate striker moves, the main sear spring causes the main sear to return to its before-firing position; 
 the intermediate striker, upon being urged rearward by the bolt assembly in a cocking action, engages the forward facing ramped face of the main sear tab, causing the main sear to deflect out of the path of the intermediate striker; 
 the intermediate striker compresses the main spring; 
 the intermediate striker moves in a forward direction causing the lock face of the intermediate striker to engage the rearward facing flat face of the main sear tab, causing the main sear to move forwardly, causing the hook-shaped cutout of the main sear to engage with the shelf of the auto sear; 
 releasing the trigger causes the trigger body to move from the after-firing position to the before-firing position, causing the trigger-to-auto-sear linkage to rotate and push the auto sear from the after-firing position to the before-firing position, which allows the main sear to drop until the main sear engages the main sear supporting arm of the shelf sear. 
 
 
     
     
         9 . The apparatus of  claim 8  further comprising:
 a selector switch having a lever element coupled to a barrel element, the barrel element having a shelf-sear detent and a selector-switch-to-auto-sear-linkage detent, the selector switch having three selectable positions:
 a safety position in which the shelf-sear detent does not face the shelf sear, preventing the shelf sear from moving in response to movement of the trigger body, 
 a semi-automatic position in which the shelf-sear detent faces the shelf sear and in which the selector-switch-to-auto-sear-linkage detent faces a selector-switch-to-auto-sear linkage, and 
 an automatic position in which the shelf-sear detent faces the shelf sear and in which the selector-switch-to-auto-sear-linkage detent does not face the selector-switch-to-auto-sear linkage; 
 
 the selector-switch-to-auto-sear linkage rotatably coupled to the auto-sear pin and having a bolt-engaging arm and a selector-switch arm that engages with the barrel element of the selector switch; 
 a selector-switch-to-auto-sear-linkage spring that urges the selector-switch-to-auto-sear linkage into engagement with the barrel element of the selector switch; 
 wherein:
 moving the selector switch to the automatic position prevents the selector-switch-to-auto-sear-linkage detent from engaging the selector-switch-to-auto-sear linkage so that the bolt-engaging arm is in a bolt-engaging position; 
 moving the selector switch to the semi-automatic position causes the selector-switch-to-auto-sear-linkage detent to engage the selector-switch-to-auto-sear linkage so that bolt-engaging arm is in a non-bolt-engaging position; and 
 the bolt assembly engaging the bolt-engaging arm of the selector-switch-to-auto-sear linkage after the bolt assembly achieves a bolt lock condition causes the auto sear to move from the after-firing-position to the before-firing position. 
 
 
     
     
         10 . The apparatus of  claim 7  wherein the trigger assembly means comprises:
 a trigger element having:
 a trigger body, 
 a trigger slot to engage a trigger pin coupled to the lower receiver about which the trigger element rotates, 
 a shelf-sear engagement arm extending from the trigger slot, 
 an adjustment screw extending from the shelf-sear engagement arm, and 
 an actuator engagement pin coupled to the trigger body frontward of the trigger slot; 
 
 a trigger spring engaged with the trigger body urging the trigger body into a before-firing position; 
 a shelf sear having:
 an elongated body that rotates around a shelf sear pivot pin coupled to the lower receiver, 
 a main-sear-supporting arm adjacent to a front end of the shelf sear elongated body, 
 an L-shaped element adjacent to a rear end of the shelf sear elongated body; 
 
 a shelf sear spring coupled to the front end of the shelf sear elongated body that urges the shelf sear to rotate about the shelf sear pivot pin; 
 a main sear having:
 a main sear front end and a main sear rear end, 
 a slot engaged with a main sear pin coupled to the lower receiver, 
 a tab having:
 a rearward facing flat face that engages the lock face of the intermediate striker when the main sear is in a before-firing position, and 
 a forward facing ramped face, and 
 
 a main-sear shelf that engages the main-sear-supporting arm of the shelf sear when the main sear is in the before-firing position; 
 
 a lift spring coupled adjacent to the main sear front end that urges the main sear to rotate about the main sear pin as constrained by the slot in the main sear; 
 an actuator having:
 a curved crossbar, 
 a first bent arm coupled to a first end of the curved crossbar, wherein the first bent arm has a first bent arm narrow section, 
 a second bent arm coupled to a second end of the curved crossbar, wherein the second bent arm has a second bent arm narrow section, and 
 the actuator being rotatably coupled to the shelf sear by the shelf sear pivot pin passing through a first bent arm pivot hole on the first bent arm and a second bent arm pivot hole on the second bent arm; 
 
 an auto link connector (ALC) having:
 a pinned arm coupled to an ALC pin hole on the first bent arm of the actuator, 
 a selector switch engagement arm, and 
 a bolt engagement arm; 
 
 wherein:
 moving the trigger body from a before-firing position to an after-firing position causes:
 the adjustment screw extending from the shelf-sear engagement arm to engage the shelf sear and cause the shelf sear to rotate about the shelf sear pivot pin so that the main-sear-supporting arm no longer supports the main sear, and 
 the actuator to rotate around the shelf sear pivot pin as constrained by interaction between the actuator engagement pin and the narrow portion of the first bent arm from a before-firing position to an after-firing position; 
 
 as a result of the main-sear-supporting arm no longer supporting the main sear, the intermediate striker causes the main sear to rotate such that the tab on the main sear no longer engages the lock face of the intermediate striker, allowing the intermediate striker to move to cause the striker to engage the valve stem to open the valve; 
 after the intermediate striker moves, the lift spring causes the main sear to move into a position to intercept the intermediate striker; 
 the intermediate striker, upon being urged rearward by the bolt assembly in a cocking action, engages the forward facing ramped face of the main sear tab, causing the main sear to deflect out of the path of the intermediate striker; 
 the intermediate striker compresses the main spring; 
 the intermediate striker moves in a forward direction causing the lock face of the intermediate striker to engage the rearward facing flat face of the main sear tab, causing the main sear to move forwardly, causing the main sear to engage with the curved crossbar on the actuator; 
 releasing the trigger causes the trigger body to move from the after-firing position to the before-firing position, causing the actuator to rotate from the after-firing position to the before-firing position, which allows the main sear to drop until the main sear engages the main sear supporting arm of the shelf sear. 
 
 
     
     
         11 . The apparatus of  claim 10  further comprising:
 a selector switch having a lever element coupled to a barrel element, the barrel element having a shelf-sear detent and an ALC detent, the selector switch having three selectable positions:
 a safety position in which the shelf-sear detent does not face the shelf sear, preventing the shelf sear from moving in response to movement of the trigger body, 
 a semi-automatic position in which the shelf-sear detent faces the shelf sear and in which the ALC detent does not face the ALC, and 
 an automatic position in which the shelf-sear detent faces the shelf sear and in which the ALC detent faces the ALC; 
 
 wherein:
 moving the selector switch to the automatic position allows the ALC detent to engage the ALC so that the bolt engagement arm is in a bolt-engaging position; 
 moving the selector switch to the semi-automatic position prevents the ALC detent from engaging the ALC so that bolt engagement arm is in a non-bolt-engaging position; and 
 the bolt assembly engaging the bolt engagement arm of the ALC after the bolt assembly achieves a bolt lock condition causes the actuator to move from the after-firing-position to the before-firing position. 
 
 
     
     
         12 . The apparatus of  claim 1  wherein the bolt assembly means comprises:
 a first part and a second part that:
 are separated by a small gap just prior to actuation of the trigger assembly, and 
 become separated by a large gap, larger than the small gap, over a projectile-firing period of time immediately after the trigger assembly is actuated, the increase in the gap size being caused by movement of the second part in response to gas entering the small gap from the output side of the valve; and 
 
 wherein the first part and the second part move together in a cocking action once they are separated by the large gap. 
 
     
     
         13 . The apparatus of  claim 12  wherein the second part comprises:
 a bolt probe; 
 a bolt lock regulator body coaxial to and fixedly coupled to the bolt probe; 
 a bolt lock bushing coaxial to the bolt probe, laterally fixed to the bolt probe, and rotatable about the bolt probe; 
 a cam pin fixedly coupled to the bolt lock bushing; and 
 a torsion spring coupled between the bolt lock regulator body and the bolt lock bushing that biases the bolt lock bushing to rotate about the bolt probe. 
 
     
     
         14 . The apparatus of  claim 13  wherein the bolt assembly means further comprises a cylindrical bolt carrier fixedly coupled to the bolt lock piston, wherein the cylindrical bolt carrier has a cam slot, wherein the cam pin extends through the cam slot and the L-shaped slot, and wherein the cylindrical bolt carrier contains the bolt lock regulator body, the bolt lock bushing, and the bolt probe. 
     
     
         15 . The apparatus of  claim 14  wherein the torsion spring biases the cam pin within cam slot and the L-shaped slot along the long leg of the L-shaped slot, toward the junction, and, guided by the cam slot, into the short leg. 
     
     
         16 . The apparatus of  claim 13  wherein the bolt probe is coupled to a source of pressurized gas at one end and to a poppet valve within the bolt lock regulator body at the other end, the poppet valve separating a pressurized chamber in the bolt lock regulator body from a pressurizable chamber between the bolt lock regulator body and the bolt lock piston. 
     
     
         17 . The apparatus of  claim 16  wherein the poppet valve comprises a spring and a hollow set screw, wherein rotation of the hollow set screw adjusts a tension in the spring and a pressure required to open the poppet valve so that the pressurized chamber communicates with the unpressurized chamber. 
     
     
         18 . The apparatus of  claim 17  wherein the hollow set screw provides gaseous communication from the pressurizable chamber to the gap between the bolt lock regulator body and the bolt lock piston. 
     
     
         19 . An apparatus comprising:
 a lower receiver means having a trigger assembly means wherein the trigger assembly means is select-fire striker based and fits within select-fire hammer based trigger constraints;   an upper receiver, coupled to the lower receiver, having a bolt assembly means and an L-shaped slot means, wherein the L-shaped slot means has a long leg, a junction, and a short leg, and wherein the bolt assembly interacts with the L-shaped slot means;   the upper receiver means having a rear end for coupling with a compressed gas power source; and   a gas path means coupled to the compress gas power source for firing a projectile through a barrel and for cocking the bolt assembly.   
     
     
         20 . An apparatus comprising:
 a lower receiver having a trigger assembly means;   an upper receiver, coupled to the lower receiver, having a bolt assembly means and an L-shaped slot means, wherein the L-shaped slot means has a long leg, a junction, and a short leg, and wherein the bolt assembly means interacts with the L-shaped slot means;   the upper receiver having a rear end to which a compressed gas power source can be coupled; and   a gas path means coupled to the compress gas power source for firing a projectile through a barrel and for cocking the bolt assembly means;   wherein the bolt assembly means comprises:
 a first part and a second part that:
 are separated by a small gap just prior to actuation of the trigger assembly, and 
 become separated by a large gap, larger than the small gap, over a projectile-firing period of time immediately after the trigger assembly is actuated, the increase in the gap size being caused by movement of the second part in response to gas entering the small gap from the output side of the valve; and 
 
 wherein the first part and the second part move together in a cocking action once they are separated by the large gap.