Method and mechanism for automatic regulation of gas flow when mounting a suppressor to a firearm

A gas system includes a gas block having a gas port for directing propellant gases received from a gas port of a barrel of a firearm into the gas system to cycle an auto loading feature of the firearm. A spring-loaded plunger assembly positioned within the gas block includes a plunger component having a plurality of gas ports and a plunger cap at a forward end, wherein the position of the plunger component within the gas block automatically controls an amount of gas that is allowed to enter the gas system. Mounting a suppressor to the muzzle of the barrel depresses the plunger cap and drives it linearly rearward causing the plunger component to rotate to automatically restrict the volume of propellant gases directed into the gas system through a restricted flow gas port in the plunger component.

TECHNICAL FIELD

The embodiments of the invention generally relate to gas operating systems for firearms and, more particularly, to automatic gas regulation systems for firearms.

BACKGROUND OF THE INVENTION

Semi-automatic firearms, such as rifles and shotguns, are designed to fire a round of ammunition, such as a cartridge or shotshell, in response to each squeeze of the trigger of the firearm, and thereafter automatically load the next shell or cartridge from the firearm magazine into the chamber of the firearm. During firing, the primer of the round of ammunition ignites the propellant (powder) inside the round, producing an expanding column of high pressure gases within the chamber and barrel of the firearm. The force of this expanding gas propels the bullet/shot of the cartridge or shell down the barrel.

In semi-automatic and automatic rifles and shotguns that rely on such gases from firing to drive operation of the firearm, gas from a fired cartridge is directed to a gas piston or the bolt carrier to cycle the action of the firearm. For example, upon firing a cartridge in a firearm having a direct gas impingement system, high-temperature, high-pressure gas follows the exiting projectile down the barrel; and a portion of the gas from the fired cartridge travels into a port and along a gas tube, rearwardly to a gas key that is coupled to the bolt carrier and includes an internal port to allow the high-pressure gas to flow against the bolt carrier. As the gas expands, the pressure from the gas drives the bolt carrier and bolt apart. The bolt carrier and bolt continue to be driven apart until the bolt rotates following the cam path and unlocks from the barrel extension. The bolt carrier and bolt then translate rearwardly against the return spring located in the buttstock, extracting the empty cartridge. Thereafter, forward movement of the bolt and bolt carrier by the return spring loads a next cartridge from the ammunition magazine and returns the bolt. The bolt returns to a locked position for firing.

In standard auto loading rifles, the addition of a suppressor to the muzzle of the firearm can generate an increase in bore pressure, causing the rifle to cycle faster than it would normally cycle if the suppressor were not installed. In known systems, the operator manually switches a gas regulating device to modify the operating characteristics of the firearm to compensate for this increased bore pressure. This manual switch will typically have a lever or rotational plug that requires the operator to manually switch the system from one setting to the other. In a manually switched gas system, gases are either diverted (bled off) or restricted in order to reduce the overall energy available to operate the firearm.

SUMMARY

The embodiments disclosed are directed to a system and method in which the action of installing a suppressor on the firearm directly actuates a regulating mechanism to reduce the initial energy available to a gas operating system and to match operating speeds between suppressed and unsuppressed operation of the firearm.

In an autoloading firearm, installing a suppressor on the firearm will typically cause the cyclic operation of the firearm to speed up due to residual pressures in the suppressor and bore of the firearm. Commonly available systems require the manual activation of a regulator to reduce the initial energy available to the operating system to balance the extra energy imparted by the residual bore pressure.

In one embodiment, an auto regulating gas system is provided for an auto loading firearm wherein the firearm includes a barrel having a bore, at least one gas port, and a muzzle. The gas system includes a gas block attached to the barrel to redirect a volume of propellant gases to cycle the auto loading firearm, the gas block including at least one gas port for directing propellant gases received from the at least one gas port of the barrel into the gas system to cycle the auto loading firearm. A spring-loaded plunger assembly is at least partially positioned within the gas block. The plunger assembly includes a plunger component having a plurality of gas ports and a plunger cap at a forward end, the plunger cap having at least one of a cam pin and a cam path, wherein the position of the plunger component within the gas block automatically controls an amount of gas that is allowed to enter the gas system. Mounting a suppressor to the muzzle depresses the plunger cap and drives it linearly rearward causing the plunger component to rotate as the cam pin travels along the cam path to automatically restrict the volume of propellant gases directed into the gas system through a restricted flow gas port in the plunger component.

In another embodiment, an auto regulating gas system for an auto loading firearm is provided, including a gas block attached to the barrel and configured to redirect a volume of propellant gases to cycle the operation of the firearm, the gas block having at least one gas port for directing propellant gases received from at least one gas port of the barrel into the gas system; a flow regulator at least partially positioned in the gas block, the flow regulator comprising a regulator body rotatably positioned in a passageway connected to the at least one gas port of the gas block, wherein a position of the regulator body in the passageway controls an amount of gas that is allowed to enter the gas system; and a linkage comprising a plunger part configured to extend forwardly from the gas block for being engaged and moved rearwardly by a suppressor mounted to the muzzle end of the firearm barrel. The linkage further generally will be configured to rotate the regulator body in the passageway by an amount as needed to control an amount of gas that is allowed to enter the gas system in response to the plunger part being engaged and moved rearwardly by the suppressor mounted to the muzzle.

Another aspect of this disclosure is the provision of a method of regulating a gas system for an auto loading firearm. Such a method will include mounting a suppressor to a muzzle of a barrel of the firearm wherein a linkage is engaged by the suppressor in response to the mounting of the suppressor to the muzzle of the barrel of the firearm. The linkage is operable to rotate a flow regulator in response to the linkage being engaged by the suppressor mounted to the muzzle. The flow regulator is operable to adjust an amount of gas that is allowed to enter the gas system in response to the rotation of the flow regulator.

DETAILED DESCRIPTION

The following description is provided as an enabling teaching of embodiments of the invention including the best, currently known embodiment. Those skilled in the relevant art will recognize that many changes can be made to the embodiments described, while still obtaining the beneficial results. It will also be apparent that some of the desired benefits of the embodiments described can be obtained by selecting some of the features of the embodiments without utilizing other features. Accordingly, those who work in the art will recognize that many modifications and adaptations to the embodiments described are possible and may even be desirable in certain circumstances. Thus, the following description is provided as illustrative of the principles of the invention and not in limitation thereof, since the scope of the invention is defined by the claims.

As described in the embodiments herein, the use of a cam path to transfer linear or translatory motion of the plunger cap or part into rotational motion of the plunger component or flow regulator body is a unique feature that regulates the amount of propellant gas being allowed to enter the gas tube when a suppressor is attached to the end of the firearm muzzle. The disclosed embodiments improve the reliability and durability of the firearm when operating in a suppressed condition or mode. This provides the further advantage of the firearm being less prone to carbon fouling which causes the mechanism to become stuck in one position.

FIG. 1Aillustrates an isometric view of the auto regulating gas system and linkage in one embodiment.FIGS. 1B-1Gdepict various elevation views of the auto regulating gas system and linkage in an exemplary embodiment. Specifically, relative to the orientation of the isometric view ofFIG. 1A,FIG. 1Bshows a front side view;FIG. 1Cshows a right side view;FIG. 1Dshows a back side view;FIG. 1Eshows a top view;FIG. 1Fshows a left side view; andFIG. 1Gshows a bottom view of the firearm. The gas-operated mechanism of an auto loading firearm F can be adjusted automatically using a flow regulating mechanism or plunger assembly10when an accessory is attached to the muzzle14of the firearm. The flow regulator or plunger assembly10includes a plunger part or cap18that is mounted for reciprocating movement, and a plunger component36. The plunger component36is capable of rotation and includes at least two orifices, ports or other guideways or passages that control the flow of propellant gas into the gas tube44during operation of the firearm. The barrel30of the firearm comprises a chamber to accept a cartridge, a bore29(FIGS. 1F and 2), one or more gas orifices or ports31(FIG. 2), and the muzzle14.

A gas block34can be attached to the barrel30to redirect the propellant gases to cycle the action of the firearm F through the use of a gas tube44that redirects the gases into the bolt carrier (not shown). Pins62,64or one or more other suitable fasteners retain the gas block34to the barrel30.FIGS. 1B-1Gschematically illustrate the body of the gas block34, with portions of the body of the gas block being shown as being transparent or see through, and/or with portions of the body of the gas block being omitted, such as for illustrating features of the auto regulating gas system and linkage that may be normally hidden from view within the gas block.

The barrel30of the auto loading firearm F may have a suppressor40attached to its muzzle end14. Attaching the suppressor40to the muzzle14forces the plunger part or cap18to move linearly rearward which rotates the plunger component36in order to restrict the amount of gas entering the gas tube44, thereby reducing the amount of energy used to cycle the firearm.

FIG. 2illustrates a side view of the auto regulating gas system and linkage in an unsuppressed setting or condition in one embodiment.FIG. 3illustrates a side view of the auto regulating gas system and linkage in a suppressed setting or condition. As shown inFIG. 3, a rear end41of the suppressor40is engaged against a front end19of the plunger part or cap18, so that the plunger part or cap is pressed farther into the gas block inFIG. 3as compared toFIG. 2. The plunger part or cap18can be depressed or moved rearwardly in response to the suppressor40being mounted to the muzzle14, because this mounting can cause the rear end41of the suppressor40to be engaged against the front end19of the plunger part or cap18.

As shown inFIGS. 2-3, gas block34is mounted to the barrel30of a semi-automatic or fully automatic firearm F. InFIG. 2, a muzzle device20(e.g., flash hider) is attached to the muzzle end14of the barrel30of the firearm F. For example, the muzzle device20may be attached to the muzzle14by way of a threaded or other releasable connection, and which can comprise a cooperative, direct engagement between at least one internal helical thread of the muzzle device and at least one external helical thread of the muzzle. Such an attachment alternatively may be provided in any other suitable manner.

Gas from at least one port31(FIG. 2) in the barrel30will enter the gas block34through at least one gas port32and is routed through a gas tube44back to the bolt carrier (not shown). The spring-loaded plunger assembly10includes the plunger part or cap18which protrudes from the front of the gas block34. A cross pin26extends at least partially through the gas block34and into an outer annular groove37in a shaft of the plunger component36to at least partially retain the plunger component36inside of the gas block in a manner that allows rotation of the plunger component inside of the gas block but restricts translational movement of the plunger component36. The rearward end section of the plunger component36may be referred to as a flow regulator body38that is in communication with the gas port32such that gas flow from the barrel30into the gas block34must pass by or through the regulator body38of the plunger component36before entering the gas tube44. The plunger assembly10is designed so that rotation of the plunger component36, and/or the rotation of the flow regulator body38thereof, will cause an expansion or constriction of the area through which the gas can pass on its way to the gas tube44. The plunger cap18of the plunger assembly10at least partially includes a cam-type mechanism (shown inFIG. 6) that transitions linear motion of the plunger cap18into rotational motion of the plunger component36.

A suppressor40may be mounted to the muzzle14of the barrel30in any suitable manner, such as by being mounted directly to the muzzle by way of a threaded connection comprising cooperative, direct engagement between at least one internal helical thread of the suppressor and at least one external helical thread of the muzzle, or the suppressor may be indirectly mounted to the muzzle. For example,FIGS. 1B, 1D, 1E, 1F, 1G and 3show the suppressor40mounted to a flash hider or suppressor or similar device20that is already mounted on the muzzle end14of the barrel30, such as by way of a threaded connection comprising cooperative, direct engagement between at least one internal helical thread of the suppressor and at least one external helical thread22of the muzzle device, wherein these threads are cooperatively configured for causing relative axial movement between the suppressor40and the muzzle14of the barrel30in response to relative rotation therebetween. Alternatively, the suppressor40may be mounted to the muzzle14of the barrel30in any other suitable manner. Additionally, other suppressor designs or configurations also can be used.

In one embodiment shown in the drawings, the gas block34can be located and/or configured so that when a suppressor40, as shown inFIG. 3, is mounted over a flash hider or other device20that is already mounted on the muzzle end14of the barrel30, the suppressor40depresses the plunger part or cap18, which causes the plunger component36to rotate, thereby constricting the amount of gas reaching the gas tube44. Alternatively, the gas block34and/or other features may be located or configured so that when a suppressor40is mounted directly to the muzzle14of the barrel, the suppressor40depresses the plunger cap18, which causes the plunger component36to rotate, thereby constricting the amount of gas reaching the gas tube44.

FIG. 4illustrates a side view of the plunger component36in an unsuppressed setting, condition or state, in one embodiment. As best understood with reference toFIG. 4, a relatively large gas port42that extends through the sidewall of the regulator body38is aligned with and open to an end of the gas block's gas port31, the regulator body's large gas port42is open to a rearwardly open cavity39of the regulator body38, and the regulator body's cavity39is open to the interior of the gas tube44by way of an internal passage35defined in the gas block34. The regulator body38may be positioned in the passage35or in a bore, cavity or other passageway that is open to the passageway35. The plunger component36also can be configured so that it does not restrict flow of gas within the gas block34from the gas port32to the gas tube44. The regulator or plunger assembly10may be positioned in and protrude forwardly out of a longitudinally extending main passageway or bore55in the gas block34, wherein this longitudinally extending main bore55extends forward from the internal passage35, and the internal passage35may be a rear portion of the longitudinally extending main bore55of the gas block.

FIG. 5illustrates a side view of the plunger component36in a suppressed setting or state. As compared toFIG. 4, in the configuration shown inFIG. 5the plunger component36including the regulator body38has rotated to a position where gas traveling from the gas port32to the gas tube44is regulated/constricted by relatively small gas port43in the regulator body38of the plunger component36. The small gas port43can be smaller than both the gas port32in the gas block34and the relatively large gas port42of the regulator body38, thus reducing the amount of gas allowed to drive the system. Opening43is also referred to herein as restricted flow gas port43. As shown inFIG. 5, the relatively small gas port43that extends through the sidewall of the regulator body38is aligned with and open to an end of the gas block's gas port31, the regulator body's small gas port43is open to the rearwardly open cavity39of the regulator body38, and the regulator body's cavity39is open to the interior of the gas tube44by way of the internal passage35defined in the gas block34. In a suppressed setting or state, the regulator body's large gas port42is obstructed or closed relative to the gas block's gas port31. In the unsuppressed setting or state, the regulator body's small gas port43is obstructed or closed relative to the gas block's gas port31.

FIG. 6illustrates an interface for the cam pin-plunger-plunger cap in an exemplary embodiment. As shown inFIG. 6, a cam follower or pin50fixedly connected to and extending outwardly from a forward portion of the plunger component36extends into and is guided by the cam or cam path52that is machined into the plunger cap18, wherein the cam pin and path50,52are cooperative for controlling relative axial and rotational movement between the plunger cap18and the plunger component36. This demonstrates an example of how a linkage that may comprise the plunger cap18, plunger component36, cam pin50and cam path52can convert linear translation of the plunger cap18into rotational movement of the regulator body38of the plunger component36.

As best understood with reference toFIG. 7, a substantially cylindrical forward shaft56of the plunger component36extends through a substantially cylindrical opening58in the rear end of the plunger cap18, with the outer diameter of the shaft56being slightly smaller than the diameter of the opening58for allowing both relative axial and rotational movement between the plunger cap18and the plunger component36. The cam pin50and cam path52are cooperative for restricting yet allowing predetermined relative axial and rotational movement between the plunger cap18and the plunger component36.FIG. 7illustrates at least one plunger spring54positioned within an internal chamber or cavity within the plunger cap18. The plunger spring54provides constant tension between the plunger cap18and the plunger component36so that the plunger component36does not move under normal operation of the firearm. The spring54presses the plunger cap18and the plunger component36away from one another, but the cam pin50and cam path52prevent the plunger cap18from traveling off the end of the shaft56of the plunger component36.

Due to the large amount of carbon and combustion by-product build-up that can occur in gas blocks, this embodiment is superior to prior plunger devices that rely solely on linear motion of a plunger to constrict flow from the gas block. As fouling and carbon build-up occurs in the gas block, prior plunger devices can prevent a linear plunger from translating properly. As disclosed herein, linear motion of the plunger cap18causes rotational motion of the plunger component36via a cam pin50and cam path52. It only takes a very slight rotational motion of the plunger component36to change the gas setting, reducing the likelihood that the plunger assembly10will get stuck. In one embodiment, the amount of rotation of the plunger component36is around 60°.

In operation, a gas block34with a spring loaded plunger assembly10, having one end protruding from the muzzle side of the gas block34, are attached to firearm F so that when a suppressor40is mounted to the muzzle device20, the suppressor40depresses the plunger cap18. The plunger cap18interfaces with the plunger component36via a cam pin50and cam path52that causes the plunger component36to be rotated when the cap18is translated linearly. When the suppressor40is fully attached, the plunger component36will have rotated so that the plunger component36partially obstructs the flow of gas between the gas port32in the gas block34and the gas tube44via the restricted flow gas port43in the plunger component36. The spring54can be located between the plunger component36and the plunger cap18so that when the suppressor40is not mounted to the muzzle device20, the spring force causes the cap18and plunger component36to return to their original positions. The plunger assembly10is retained within the gas block via a cross pin26. In one embodiment, the cross pin26is retained to the gas block34via a spring plunger and has a detent at the open and closed position.

It is known that the addition of a suppressor40to a semi-automatic firearm F can have adverse effects on the reliability and durability of the firearm due to the suppressor. As illustrated inFIG. 8, the disclosed embodiments improve firearm reliability by allowing the firearm to maintain the same bolt velocity in both the unsuppressed and suppressed settings.

In one embodiment, the regulator or plunger assembly10can be disassembled only when the plunger assembly10is removed from the gas block34. The plunger assembly10may be removed from the gas block34by at least partially withdrawing the cross pin26and then pulling the plunger assembly out of the front of the gas block. Then, the plunger assembly10can be disassembled by removing the cam pin50from the front shaft56of the plunger component36, so that the plunger cap18may be removed from the plunger component36. More specifically, the plunger cap18may be removed from the plunger component36by depressing the plunger cap18to the bottom of its stroke, and then rotating the plunger component36so that an end of the cam pin50aligns with a hole in the plunger cap18, wherein the hole in the plunger cap may be located at the opposite side of the plunger cap from the cam path52. Once the subject end of the cam pin50is aligned with the subject hole, the camp pin can be pushed out from the opposite side via a punch or bullet tip. The cam pin50has a shoulder on one end (not shown) to prevent the cam pin50from becoming disassembled during operation.

In some embodiments, the gas block34could have one or more slot cuts that interface with the plunger cap18so as to prevent rotation of the plunger cap18during operation. For example, the plunger cap18can include one or more wings or lateral protrusions60extending outwardly from the body of the plunger cap, wherein the protrusions60respectively extend outwardly through forwardly and laterally open slots62in the gas block34.

The plunger cap18includes a feature or features that allow the operator to pull the plunger assembly10out of the front of the gas block34using a bullet tip, fingers, spent cartridge, or other tool. For example and reiterating from above, in one example the plunger assembly10may be removed from the gas block34by at least partially withdrawing the cross pin26and then pulling the plunger assembly out of the front of the gas block.

The corresponding structures, materials, acts, and equivalents of all means plus function elements in any claims below are intended to include any structure, material, or acts for performing the function in combination with other claim elements as specifically claimed.

Those skilled in the art will appreciate that many modifications to the exemplary embodiments are possible without departing from the scope of the present invention. In addition, it is possible to use some of the features of the embodiments disclosed without the corresponding use of the other features. Accordingly, the foregoing description of the exemplary embodiments is provided for the purpose of illustrating the principles of the invention, and not in limitation thereof, since the scope of the invention is defined solely by the appended claims.