MULTI-CHAMBER SUPPRESSOR FOR MULTI-BARREL ROTARY MACHINE GUN

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates generally to suppressors for minimizing the sound and burning gun powder flash signatures of multi-barrel machine guns having an array of gun barrels mounted for power driven rotation about a central axis. More particularly, this invention concerns a suppressor device having multiple cartridge gas receiving blast chambers, each receiving the cartridge gas and burning gun powder flash from a single gun barrel and each being isolated from the cartridge gas and burning gun powder flash from other gun barrels of the multi-barrel array. Even more specifically this invention concerns a multi-chamber suppressor system for multi-barrel rotary machine guns that employs modular supported attachment of the suppressor to a clamp mechanism for releasably mounting a suppressor system to the multi-barrel array of a machine gun, to facilitate simple and efficient installation and removal of the suppressor system from the gun barrel array of a multi-barrel machine gun. This invention also provides for efficient sealing of the barrel entrance into the individual blast chambers of the suppressor body, for containing the cartridge gas blast and preventing cartridge gas escape from the muzzle/suppressor interface of each gun barrel with the suppressor body.

Description of the Prior Art

The term “gatling gun”, from the standpoint of this specification, concerns a rapid-firing multiple-barrel firearm which was invented in 1861 by Richard Jordan Gatling during the American Civil War. It is an early machine gun and is the forerunner of the modern rotary motor driven rotary cannon. Its operation is centered on a cyclic rotary multi-barrel design which facilitates cooling and synchronizes the firing-reloading sequence. The barrels, are mounted for powered rotation about a central axis, with each barrel firing a single time during each revolution of the barrels. Beginning in the 1960's gatling style rotary motor powered machine guns were developed and have found wide use, especially by the American military. Gatling style machine guns have been mounted on vehicles, helicopters, boats and airplanes and have been provided in the form of ground based firing platforms. One gatling style machine gun in use at the present time is identified as the “M-134 Minigun”, and has a firing rate of up to 6,000 rounds “rpm” or more per minute.

In a gatling style machine gun “dwell time” is of significant importance. Dwell time is the amount of time that each bolt is locked in battery. While locked in battery the bolt and gun are able to contain and withstand the pressure involved with a firing cartridge and all pressure is directed through the firing barrel. This cartridge gas pressure in a 7.62 NATO specification gun with a 22 inch barrel is completely dissipated and returns to atmospheric pressure in no longer than 4 milliseconds. The bolt remains locked in battery, after the firing pin strikes a cartridge in a cartridge chamber of a barrel, for a specific dwell time.

When an excessively large contained volume of space is added to the Minigun, such as that added with the suppressor set forth in U.S. Pat. No. 11,604,042 B1, the total volume of the suppressor is not evacuated during the allotted dwell time. Thus this type of suppressor is not in tune with or specifically designed to work within the design limitations of a gatling style machine gun such as the M-134 Minigun, which fires 7.62 mm NATO rounds, or for example the XM214 Microgun, which fires 5.56 mm NATO rounds. This suppressor designs presents higher than atmospheric pressures in the chambers that remain even as the bolt is unlocking. This allows higher pressure gas to escape into the breech area of the gun, thus compounding with the gas that is already escaping the silencer through the empty barrels; all caused by the shared volume of the entire suppressor chamber. It is desirable, therefore, to provide a suppressor wherein the cartridge gas of a firing barrel is totally isolated from the non-firing barrels of the rotary multi-barrel array of a gatling style machine gun.

Other suppressor designs for use in sound and flash suppression of multi-barrel rotary machine guns, such as the M-134 Minigun, rely specifically on sharing the volume of the suppressor with the cartridge gas being discharged from all of the barrels of the weapon. The silencer set forth is U.S. Pat. No. 11,604,042 B1 of Paulson is an example of conventional suppressor design, since the cartridge exhaust gas from each of the barrels of a multi-barrel rotary machine gun is discharged into a single blast chamber of the suppressor and is then vented through other chambers, i.e., shared volume, before being discharged from projectile openings and exhaust ports located at the forward end of the suppressor body.

The suppressor system of the present invention however, specifically isolates each firing event from another, thus enhancing operation of the machine gun by completely preventing any cartridge gases generated by a firing barrel from entering the machine gun via any of the other non-firing barrels. The volume of each individual suppressor chamber is specifically derived and determined to provide the maximum sound suppression possible without adding so much volume that residual pressure will exist in a barrel while the breech bolt begins to unlock. The suppressor system of the present invention will not compromise the established/or predetermined dwell time that is allotted to each individual firing event.

SUMMARY OF THE INVENTION

It is a principal feature of the present invention to provide a novel sound and burning gun power flash suppressor technology for multi-barrel rotary machine guns, providing a suppressor unit that does not share cartridge gas volume between the barrels and the blast chambers of the suppressor unit, but rather isolates them. This feature of the invention prevents any cartridge gas pressure from a firing event of a gun barrel from entering the non-live gun barrels, which otherwise would lead to excessive fouling, heat transfer and bolts unlocking while cartridge gas pressure remains in the barrel, thus significantly compromising the component life of a weapons system.

It is another feature of the present invention to provide a novel sound and flash suppressor system for a multi-barrel rotary machine gun in the form of a multi-piece assembly that allows for a variety of other barrel/muzzle device options to be attached in addition to the suppressor system. This feature also allows the use of different materials in both the upper and lower sections of the assembly to best fit weight, strength and material requirements that may vary depending on intended use. This feature accommodates air vs. ground handling and shipment, barrel length, overall length requirements or limitations for clearance concerns and to facilitate ease of ingress and egress.

It can also be a feature of this invention to incorporate a pressure exhaust system in the suppressor to allow for excessive pressure to more rapidly evacuate from the suppressor and permits suppressor pressure to return to ambient conditions more quickly. The pressure exhaust system can be used to maintain a preferred bleed-off time even when larger silencer chamber volumes are employed for quieter operation and more sound suppression.

It is a feature of this invention, aside from the internal form of the suppressor system, to apply these features to a multitude of different diameter, shape and length combinations to best fit the caliber and overall noise reduction requirement of the prospective weapon system.

Briefly, the various objects and features of the present invention are realized through the provision of a suppressor system having a clamp section that is adapted to be removably secured to a rotatable array of machine gun barrels and a suppressor member that is removably mounted to the clamp section by means of a threaded connection. The threaded connection has threads that are tightened by rotation and vibration of the barrel array during operation of the machine gun rather than becoming loosened.

The suppressor member of the suppressor system has a body structure that is divided into a plurality of suppressor blast chambers that are completely isolated from any of the other blast chambers of the suppressor. Each of the gun barrels of the rotatable multi-barrel array has its muzzle end engaged within a muzzle entry port of one of the blast chambers of the suppressor body and uniquely sealed to prevent cartridge gas pressure from back-flowing past the muzzle entry port to the atmosphere or to another of the isolated blast chambers.

Centrally of the suppressor body a cooling passage is defined, and is isolated from the blast chambers. In some cases a fixed turbine fan blade is present within the cooling passage and is rotated along with rotation of the suppressor member to cause movement of air from the atmosphere through the cooling passage for cooling the suppressor during operation of the machine gun.

The suppressor member of this invention may be adapted to the manner the machine gun is intended to be used. The suppressor body may be shortened or lengthened and its size may be enlarged or reduced with regard to the character of the ammunition being used and the number of internal baffles that are present within each of the multiple blast chambers of the suppressor body for designed control of the sound and flash signatures of the suppressor. It is intended that the suppressor body section have no relatively moveable parts, thus it is not capable of being assembled or disassembled. Though it may be possible to manufacture the suppressor system by means of another process, tests have indicated that the additive manufacturing process, i.e. 3-D Printing from a metal powder of high nickel content according to a computer program provides excellent results. Since the clamp member and the suppressor body are joined by a threaded connection and the clamp member is typically not subject to cartridge gas pressure, the clamp member may be manufactured in any suitable manner, though the suppressor body is best produced by additive manufacture such as 3-D Printing.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the preferred embodiment thereof which is illustrated in the appended drawings, which drawings are incorporated as a part hereof.

It is to be noted however, that the appended drawings illustrate only a typical embodiment of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

In the Drawings:

FIG. 1 is an isometric illustration showing a mounting base and support and positioning stem for supporting and positioning a suppressor member relative to the rotary multi-barrel array of a machine gun;

FIG. 2 is a side elevation view showing further details of the mounting base and support and positioning stem of FIG. 1;

FIG. 3 is a transverse section view of the base portion of the clamp and suppressor positioning stem member of FIGS. 1 and 2, taken along line 3-3 of FIG. 3;

FIG. 4 is an isometric illustration showing a multi-chamber suppressor device having an internally threaded connector, being designed for modular attachment to an externally threaded forward end of the clamp and suppressor positioning stem member of FIGS. 1 and 2;

FIG. 5 is a side elevation view of the suppressor member of FIG. 4;

FIG. 6 is an end view of the suppressor member of FIGS. 4 and 5, showing the connection end thereof;

FIG. 7 is a section view of the suppressor member, taken along line 7-7 of FIG. 6;

FIG. 8 is an isometric illustration showing a suppressor member for a multi-barrel rotary machine gun, and represent an alternative embodiment of the present invention;

FIG. 9 is a side elevation view of the suppressor member of FIG. 8;

FIG. 10 is a section view taken along line 10-10 of FIG. 9;

FIG. 11 is an end view showing the rear portion of the suppressor member of FIGS. 8-10 and showing the internal turbine style fan blade and pressure relief sectional divider of the section view of FIG. 10;

FIG. 12 is an isometric illustration showing a suppressor member for a multi-barrel rotary machine gun and emphasizing the rear connection end portion thereof, the isometric illustration representing another alternative embodiment of the present invention;

FIG. 13 is a side elevation view showing the suppressor member of FIG. 12;

FIG. 14 is a transverse section view taken along line 14-14 of FIG. 13;

FIG. 15 is an end view of the suppressor member of FIGS. 12 and 13;

FIG. 16 is a longitudinal section view taken along line 16-16 of FIG. 15;

FIG. 17 is a side elevation view showing a forward portion of muzzle portion of a gun barrel being positioned within a nozzle receiving port structure of the suppressor body of FIGS. 4, 8 and 12;

FIG. 18 is a section view taken along line 18-18 of FIG. 17 and showing a nozzle port structure of the suppressor body in relation with the rear end panel portion of the suppressor and with a gun barrel and a nozzle sealing mechanism; and

FIG. 19 is an isometric illustration showing a nozzle port in the rear end panel of the suppressor body of FIGS. 4, 8 and 12.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring now to the drawings and first to FIG. 1, a clamp member is shown generally at 10, having a clamp base shown generally at 12 that is composed of an annular rim 14 defining opposed fastener openings (e.g., bolt openings 16) that are surrounded by a bolt head receptacle 18. The opposed bolt openings receive a cross-bolt 20 having a bolt head 22, typically of hexagonal configuration, which is prevented from rotation when seated within the bolt head receptacle 18. After the suppressor system has been properly positioned within the multi-barrel array during suppressor installation, a castellated nut 24 is threaded to the cross-bolt and tightened to releasably secure the suppressor system to the multi-barrel array and secured with a cotter pin.

The annular rim 14 is connected with an anchor panel 26 having a plurality of barrel receptacle openings 28 within which the multiple barrels of the rotary machine gun are positioned when the suppressor system is mounted to the multi-barrel array. A tubular suppressor support and positioning stem 30 has its rear end portion 31 connected with the anchor panel 26 and has a forward externally threaded end 32. The tubular suppressor support and positioning stem 30 defines an internal cooling passage has multiple cut-outs 34 in its tubular wall to minimize its weight and to facilitate cooling. Likewise, multiple cut-outs 33 are provided at the juncture of the circular anchor rim 14 with the generally planar base panel 26 to minimize weight. The anchor base 12 and the suppressor support and positioning stem 30 provide for support and proper positioning of a suppressor member 40 having a suppressor body 44 shown in FIGS. 4-7. The forward externally threaded section 32 of the suppressor support and positioning stem 30 is threaded into an internally threaded rearwardly projecting section 43 of a suppressor connector 42 of the suppressor body 44. The threaded connectors 32 and 42 as shown in FIGS. 4, 8 and 12 have left-handed threads to ensure a thread tightening effect on the suppressor unit as opposed to a loosening effect when the machine gun is operated and the multi-barrel array and the suppressor system are spinning during firing activity. The suppressor unit resists loosening when located into position by the multi-barrel array. Even if the suppressor unit 40 were to try to loosen, such as due to vibration during firing activity, it cannot become loosened when installed on the multi-barrel array of the machine gun. As depicted, in some embodiments, the suppressor connector 42 can define fastener hole(s) s through which fastener(s) can be inserted to secure the suppressor connector 42 to the positioning stem 30. As depicted, thru-holes 41, 45 can be defined in the suppressor connector 42 and a fastener can be inserted through one or more of the thru-holes 41, 45. In an example, a cotter-pin can be inserted through the thru-holes 41, 45, thereby preventing rotation of the suppressor connector 42 in relation to the positioning stem 30.

The suppressor unit of FIGS. 4 and 5 has external wall structure and internal baffle structure that are immoveable relative to one another, being preferably formed by additive manufacturing, i.e., 3-D Printing from a metal alloy powder having a temperature tolerant high nickel content. The additive manufacturing process establishes an individual blast chamber within the suppressor body 44 for each of the multiple barrels of the rotary barrel array of the machine plurality of barrel muzzle ports 48 that each receive the muzzle end 52 of a machine gun barrel 54 as best shown in the longitudinal section view of FIG. 18. Barrel 54 defines a generally cylindrical sealing section 56 near its forward end and defines a muzzle entry section 58 of smaller dimension than the cylindrical sealing section 56 that extends from the sealing section 56 to the forward end 60 of the gun barrel as shown in the section view of FIG. 7. The rear wall panel 46 of the suppressor body 44 defines a barrel muzzle port 48 for each of the multiple gun barrels that make up the multi-barrel array of the machine gun. At each of these barrel muzzle ports a barrel entry projection 62 extends from the rear suppressor panel 46 into the blast chamber 50 of the suppressor as shown best in FIG. 18. As shown in FIGS. 17-19, each of the muzzle port mechanisms 48 establishes uniquely sealed barrel muzzle entrance to one of the blast chambers 50 of the suppressor member 40. Each barrel entry projection 62 is of slightly curved tubular configuration terminating at a rather sharp circular edge 64 that has close fitting engagement with the forward end 60 of the muzzle entry section 58 of the gun barrel 54.

In order to ensure a positive seal between the gun barrel and the rear wall structure 46 of the suppressor body 44 and prevent cartridge gas pressure from a blast chamber 50 of the suppressor member, a circular seal retainer groove 66 is formed in the wall structure 46 of the suppressor body within each muzzle entry port 48. A split gasket ring/s 68, preferably composed of a metal such as spring steel, is positioned within the seal retainer groove 66 and establishes sealing engagement with the cylindrical sealing surface 56 of the barrel 54. The split gasket ring/s 68 has a rectangular cross-sectional configuration so that a cylindrical sealing surface 70 of the split ring sealing gasket has metal-to-metal sealing engagement with the sealing surface 56 of the gun barrel 54. Upon firing of the gun barrel 54, cartridge gas travels through the barrel bore 55 and enters and pressurizes the blast chamber 50. This cartridge gas pressure acts on the barrel entry projection 62, tending to force it inwardly and enhancing the seal at 66 with the forward end 60 of the barrel. Any cartridge gas pressure that might manage to pass the edge seal 66 will enter the annular space 72 between the barrel entry projection 62 and the external annular surface of the barrel, where it will then act on the split ring seal 68.

The split ring seal functions in much the same manner as a piston seal in an automotive vehicle engine. Ignition of a fuel and air mixture within a piston chamber of a vehicle engine applies pressure induced force to move a piston member within a cylinder. Typically a plurality of split ring piston seals, located within circular seal grooves of the pistons, prevents leakage of pressure past the piston seals, so that virtually all of the pressure is employed as energy to drive the piston and thus provide the power for operation of the engine.

Typically, the high rate of fire of a suppressed multi-barrel machine gun, such as the M134 Minigun, causes high frequency pressure loading on the internal walls of a typical suppressor unit for a multi-barrel machine gun, which can lead to fatigue cracking and ultimate failure of the wall structure of some suppressor units that have been developed. The use of varying wall thicknesses and exhaust ports in the suppressor unit of this invention clearly address this potential problem and minimizes the potential for cartridge gas pressure stress induced failure of the body 44 of the suppressor member 40. The rear end view of FIG. 6 and the longitudinal section view of FIG. 7 emphasize the construction features of the suppressor member 40. The tubular suppressor connector 42 and an internal tubular wall 74 define a cooling passage 75 having a central opening 76 at the front end of the suppressor. This cooling passage and the cooling capability that is provided by the internal cooling passage 35 of the tubular support and positioning stem 30 assist in preventing excessive heat build-up of the suppressor member 40 during operation of the multi-barrel machine gun.

Within the body 44 of the suppressor member 40, a plurality of cartridge gas processing baffle members 78 and 80 project inwardly and rearwardly from the suppressor body 44 and from the internal tubular wall 74 and have baffle ends 82 and 84 that are disposed in spaced relation and define a projectile path shown in broken line at 86. When a projectile, such as a bullet is discharged from the bore 55 of a gun barrel of the multi-barrel array, its passage toward a distant target will be along the projectile path 86 between the baffle ends 82 and 84 and between the spaced ends 88 and 90 of outlet cartridge gas processing baffles 92 and 94. Cartridge gas, burning gun powder flash and projectiles that are fired from the gun barrel travel along the projectile path 86 and exit the suppressor member 40 from an outlet port 96 of each blast chamber that is located at the forward end panel 46.

With reference to FIGS. 8-11, a suppressor unit is shown generally at 100, that has a body structure 102 that is virtually the same, externally, as shown in FIG. 4. Its like components are indicated by like reference numerals as compared with FIGS. 4-7. As mentioned above, firing of a multi-barrel rotary machine gun, such as the M-134 Minigun, with the sound and flash suppressor of this invention mounted to its rotary multi-barrel array, causes hot cartridge gas and burning gun power to be discharged from one of the gun barrels into one of the blast chambers 50 of the suppressor 100 during each revolution of the rotary multi-barrel array. As the multi-barrel array is rotated by the drive mechanism of the machine gun each of the barrels is sequentially loaded with a round of ammunition that is in battery when it is located and locked within a cartridge chamber of one of the barrels.

With reference to FIG. 10, a tubular section 104 of the suppressor connector 42 merges with a smaller dimensioned central tubular member 106 having a forward tapered ends 108 that cooperate with the baffle members 80 to define a pressure relief port 110 for each of the blast chambers 112 of the suppressor. When a cartridge gas pulse occurs in one of the isolated blast chambers 112, a projectile being fired from the barrel that is associated with that particular blast chamber travels along the projectile path 86, moving between the baffle ends 122 and 123 and exits the suppressor at the projectile port 96 in the forward end panel 120 along with a substantial volume of the cartridge gas that is vented through the restricted opening 125 that is defined by the baffle ends 82 and 84. A substantial volume of the cartridge gas is vented from the blast chamber 112 to the atmosphere via the pressure relief port 110. Venting of the cartridge gas via the exit port 96 and the pressure relief port 110 of each of the blast chambers ensures minimal sound and flash presence when the processed cartridge gas is discharged from the suppressor.

A turbine style end is located coincident with a generally planar forward end panel 120 of the suppressor body 102. The fan blade 114 is located within the cooling passage 116 that is defined by the central tubular member 106 and is connected to the interior of the central tubular member 106 preferably by means of integral connection such as by additive manufacturing, i.e., 3-D Printing. A pressure relief sectional divider 118 extends forward from the turbine fan blade 114 and has its forward end in substantial alignment with the plane of the forward end panel 120 of the suppressor 100. It should be borne in mind that the turbine fan blade 114 is fixed with respect to the tubular cooling passage 106 and only rotates as the suppressor member is rotated by the barrel array of the machine gun.

With reference to FIGS. 12-16, a suppressor member shown generally at 125 has a suppressor body 126 having a rear body portion 128 that is substantially the same as shown in FIGS. 4 and 8. Features that are substantially identical are identified by like reference numbers. It should be noted that the suppressor member 125 has no relatively moveable parts. Preferably the suppressor body 126 is created by additive manufacturing processes, such as by 3-D Printing from a metal powder. Centrally of the suppressor body 126 is provided a tubular structure 128 that defines a central passage 130 that permits air movement for cooling. As shown in the section view of FIG. 14 a plurality of chamber partitions 132 are joined with the central tubular structure 128 and radiate outwardly to define a plurality of blast chambers 134 for processing cartridge gas and burning gun powder that is discharged into the blast chambers 134 from the bores 55 of the gun barrels 54.

As discussed above in connection with FIGS. 17-19, the muzzle of each of the gun barrels of the rotatable multi-barrel array extend through the muzzle ports 48 and have sealing mechanisms that prevent the hot, high pressure cartridge gas from escaping rearwardly from the blast chambers through the muzzle ports. Rather, the suppressor member is designed to process the cartridge gas by venting it from an entry portion 136 of each blast chamber 134 through baffle openings 138, 140 and 142 of restricted dimension, reducing the gas pressure at each baffle opening. The suppressor body may have any suitable length and any desired number of spaced internal baffles that is determined by the expected entry gas pressure in the entry portions of the blast chambers and the intended gas pressure being vented from vent or discharge ports 144 that are located at the forward end panel 146 of the suppressor body.

As the multi-barrel machine gun operates the multi-barrel array is rotated about a longitudinal axis by the rotary drive mechanism of the machine gun, and the suppressor member 100, being releasably mounted to the multi-barrel array, will be rotated along with the machine gun barrels. As the barrels are rotated, ammunition cartridges are de-linked and then fed by bolt members moving within bolt tracks of a power-driven rotor and into cartridge chambers of the gun barrels. The bolt members become locked, securing the cartridges in battery within the cartridge chambers of the barrels. This cartridge loading procedure occurs sequentially during rotation of the multi-barrel array. As each of the rotating barrels reaches its firing position, the firing pin of the bolt member is released to strike the primer of the cartridge with sufficient force to ignite the primer, causing firing of the cartridge, followed by extraction and ejection of the spent cartridge case. Each of the machine gun barrels will be fired once during each revolution of the multi-barrel array, the firing taking place at a single position for each of the barrels.

The clamp member 10 and the suppressor member are assembled by threaded connection of the external thread 32 and internal thread 43. The suppressor member, whether 40 of FIG. 4, 100 of FIG. 8 or 125 of FIG. 12 is rotated counter-clockwise relative to the clamp member to establish left-handed threaded connection of the suppressor member to the clamp member. The left-handed threads cause the threaded connection to be tightened rather than loosened during rotation of the barrel array. The clamp/suppressor assembly is then moved rearwardly with respect to the multi-barrel array, positioning the intermediate portions of the gun barrels within the barrel receptacle openings 28 of the anchor panel 26. This rearward installation movement of the clamp and suppressor assembly continues until the muzzle ends of the gun barrels become engaged and sealed within the muzzle ports 48 and muzzle entry projections 62 of the rear wall 46 of the suppressor member. The clamp member 10 is then releasably secured to the multi-barrel array by tightening of the lock nut 24 of the cross-bolt 20. To remove the clamp and suppressor assembly from the multi-barrel array, the lock nut 24 is loosened or completely removed. The clamp and suppressor assembly are then moved forwardly until clear of the multi-barrel array of the machine gun.

In view of the foregoing it is evident that the present invention is one well adapted to attain all of the objects and features hereinabove set forth, together with other objects and features which are inherent in the apparatus disclosed herein.

As will be readily apparent to those skilled in the art, the present invention may easily be produced in other specific forms without departing from its spirit or essential characteristics. The present embodiment is, therefore, to be considered as merely illustrative and not restrictive, the scope of the invention being indicated by the claims rather than the foregoing description, and all changes which come within the meaning and range of equivalence of the claims are therefore intended to be embraced therein.