EP4403869A1

EP4403869A1 - Sound suppressor

Info

Publication number: EP4403869A1
Application number: EP24152257.2A
Authority: EP
Inventors: Michael Graham Bourchier
Original assignee: Bourchier Pty Ltd
Current assignee: Bourchier Pty Ltd
Priority date: 2023-01-20
Filing date: 2024-01-16
Publication date: 2024-07-24
Also published as: US20240247901A1; AU2024200245A1

Abstract

A suppressor for a firearm, comprising a tubular body couplable to a barrel of the firearm, the body including: a bore that provides a pathway for a projectile to travel through the suppressor, the bore including an inlet section disposed at a proximal end of the body, a central section and an outlet section disposed at a distal end of the body; and a first passageway that extends axially along a length of the body and is disposed externally of the bore and is in fluid communication with the inlet section, wherein, when the suppressor is coupled to the firearm, expansion gases enter the bore through the inlet section and propel the projectile along the central section and through the outlet section, with a first flow of expansion gases passing from the inlet section into the first passageway before being expelled from the body, with energy from the first flow of expansion gases being dissipated along the first passageway to thereby reduce sound levels associated with the firing of the projectile.

Description

TECHNICAL FIELD

The present invention relates to a sound suppressor device. More particularly, the invention relates to a sound suppressor device particularly but non-exclusively suitable for use with a firearm.

BACKGROUND

During the firing of a projectile from a firearm, the combustion and subsequent expansion of propellant within a chamber of the firearm are transferred to the projectile, propelling it out through a barrel of the firearm at high speed.
The generation and expansion of the gases arising from the firing of the projectile creates significant noise, with the expulsion of the expanding gases from an end of the barrel generating a sonic wave that may cause harm to an operator of the firearm or other individuals in the vicinity. Depending on the propellant used, ingestion of the fumes and heat produced from the expulsion of the expanding gases may also be harmful. Similar issues exist in the fields of industrial steam and combustion engines where the expulsion of the expanding gases to atmosphere results in the generation of sonic waves.
Suppressors, silencers, or mufflers are known devices which aim to reduce the sound levels associated with the use of firearms. Conventional suppressors serve as pipe-like body that are screwed onto the barrel of a firearm and act as an extension thereof, either partially of fully. Such suppressors typically include internal structures such as baffles and galleries that aim to capture and direct the expanding gases along a labyrinthine path that dissipates energy associated therewith along the way, thereby reducing the sound levels or signature of the gases as they are expelled from the end of the suppressor barrel. Such internal geometries are often complex and difficult to machine, resulting in costly manufacture methods. Furthermore, such geometries can hinder the rate at which the expanding gases are expelled from the firearm, which in turn can reduce the exit velocity of the projectile and/or create back-pressure directed towards the operator and effect the firing rate of a firearm.
Whilst existing suppressors can mitigate sound levels to some extent, the performance of commercially available suppressors is a compromise between sound mitigation and usability, with existing methods of increasing sound deadening performance being limited to increasing the length (and hence weight) of the suppressor body, often resulting in a cumbersome or unwieldly device when fitted to the firearm.
As such, most suppressors commercially available reduce sound levels by between 25dB and 38dB. Given that many modern firearms produce outward sound readings of over 150dB, the sound levels resulting from use of typical suppressors is still outside of the understood medically acceptable range and capable of causing temporary or permanent hearing damage. Accordingly, it would be advantageous to have a suppressor with improved sound suppressing performance and a compact footprint. It would be beneficial for the suppressor to be simple to manufacture. It would be desirable if the suppressor enabled expanding gases arising from the use of a firearm to be expelled in a controlled manner away from an operator.
The present invention was conceived with these shortcomings in mind.

SUMMARY

In a first aspect, the invention provides a suppressor for a firearm, comprising a tubular body couplable to a barrel of the firearm, the body including: a bore that provides a pathway for a projectile to travel through the suppressor, the bore including an inlet section disposed at a proximal end of the body, a central section and an outlet section disposed at a distal end of the body; and a first passageway that extends axially along a length of the body and is disposed externally of the bore and is in fluid communication with the inlet section, wherein, when the suppressor is coupled to the firearm, expansion gases enter the bore through the inlet section and propel the projectile along the central section and through the outlet section, with a first flow of expansion gases passing from the inlet section into the first passageway before being expelled from the body, with energy from the first flow of expansion gases being dissipated along the first passageway to thereby reduce sound levels associated with the firing of the projectile.
The first passageway may extend between the inlet section and the outlet section such that the first flow of expansion gases bypasses the central section of the bore. The outlet section may include an end wall having a central orifice for the projectile to exit the bore and at least one perimeter orifice for the first flow of expansion gases to exit the suppressor. The inlet section may include an end wall having a valve providing fluid communication of the first flow of expansion gases between the inlet section and into the first passageway.
The first passageway provides an escape route for at least some of expansion gases arising from the firing of the projectile to exit the suppressor. This enables energy from the expansion gases to be dissipated along the first passageway before exiting the suppressor, thereby reducing sound levels. Further, because it is separate from the pathway of the projectile, is the first passageway serves as a bypass such that the first flow of expansion gases is diverted away from the path taken by the projectile itself and thus does not hinder the path of the projectile.
In some embodiments, the body may further include: a second passageway that extends axially along a length of the body that is disposed externally of the bore and separate from the first passageway and is in fluid communication with the inlet section or central section of the bore; wherein, when the suppressor is coupled to the firearm, a second flow expansion gases pass from the central section and into the second passageway before being expelled from the body, with energy from the second flow of expansion gases being dissipated along the second passageway to thereby reduce sound levels associated with the firing of the projectile.
The second passageway may extend to a supplementary orifice, the supplementary orifice providing a direct exit for the second flow of expansion gases from the suppressor such that the second flow of expansion gases bypasses the outlet section. The second pathway provides a second bypass along which the second flow of expansion gases arising from the firing of the projectile travels to exit the suppressor. Further, the provision of a secondary orifice enables the second flow of expansion gases to be exhausted in a direction that is different to the path of the projectile. This can be useful in dissociating the sound signature of the firearm from the location from which it is fired.
In some embodiments, the body may further include a baffle that divides the central section of the bore into a plurality of sub chambers, with the baffle having an opening permitting passage of the projectile therethrough.
The baffle may be frusto-conically shaped and oriented towards the proximal end of the tubular body. The baffle may include a tapered tip having a radius that defines the opening. The baffles are designed to capture the expansion gases arising from the detonation of the propellant, scavenging the gases off the projectile as it travels along the chamber.
The baffle may include an aperture that provides direct fluid communication between adjacent sub chambers defined thereby, such that, when the suppressor is coupled to the firearm, a third flow of expansion gases passes between adjacent sub chambers via the aperture. The aperture or apertures may be tear shaped. The aperture may be one of a plurality of apertures disposed equidistantly about a circumference of the baffle. The apertures provide a means for the third flow of expansion gases travels to travel along the central section of the bore, between adjacent sub chambers.
In some embodiments, the baffle may be one of a plurality of baffles disposed along a length of the central section of the bore, with each of the baffles having at least one aperture. The apertures of each of the baffles may be offset from the apertures of adjacent baffles, such that the third flow of expansion gases passing between sub chambers of the central bore must follow a non-linear path thereby dissipating energy and sound levels associated therewith.
The body may further include a fluid reservoir located between the inlet section and the first passageway. The fluid reservoir provides a means for rapidly expelling the expanding gases from the bore. Rapid expulsion of the expanding gases is important, for hindering the rate of expulsion can negatively affect the speed at which the projectile is released from the firearm. The tubular body may be a 3D-printed body. 3D printing provides a simple, cost-effective manufacturing method that does not require complex machining setups or machinery such as CNC lathes and the like. Further, 3D printing allows for complex geometries of, for example, the passageway(s) and baffles that would simply not be possible using conventional machining methods. For example, in some embodiments, the suppressor may further comprise a lattice-like infill that is disposed within the tubular body and dissipates energy from the expansion gasses entering into the suppressor.
The suppressor may further comprise a locking mechanism for coupling the body to the barrel of the firearm.
In some embodiments, the locking mechanism may include a first part that is integrally formed with the tubular body and configured to engage with a separate second part, the second part being configured to directly interface with the barrel of the firearm. Alternatively, the locking mechanism may include a first part that is configured to directly interface with the tubular body and configured to engage with a separate second part, the second part being configured to directly interface with the barrel of the firearm.
The first and second parts may each comprise complimentary locking elements to rotationally secure the second part to the first part. The complimentary locking elements may provide a quick release mechanism enabling the second part to be secured to the first part via a quarter turn motion.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are illustrated by way of example, and not by way of limitation, with reference to the accompanying drawings, of which:

Figure 1 is a sectional perspective view of a suppressor for a firearm according to one embodiment of the invention, illustrating a central bore providing a pathway for a projectile and a first passageway extending separately therefrom for exhausting expansion gasses arising from the firing of said projectile in a first flow;
Figure 2 is another sectional perspective view of the suppressor of Figure 1, illustrating a second passageway extending separately from the first passageway for exhausting expansion gasses therefrom in a second flow;
Figure 3 is a top view of the suppressor of Figure 1, illustrating a plurality of second passageways protruding from a perimeter of a tubular body of the suppressor;
Figure 4 is a bottom view of the suppressor of Figure 1, illustrating an orifice of the suppressor for a projectile and first flow of expansion gases to exit therethrough and a plurality of secondary orifices associated with the plurality of second passageways;
Figure 5 is a side sectional view of the suppressor of Figure 1 coupled to a barrel of a firearm, illustrating the flow paths of exhaust gases through the inlet section and into the central section of the bore of the suppressor body;
Figure 6 is an enlarged view of the central section of the suppressor of Figure 1, illustrating a projectile travelling therethrough;
Figure 7 is a cutaway perspective view of an upper region of the suppressor of Figure 1, illustrating a lattice member disposed within the tubular body;
Figure 8 is an exploded view illustrating a locking mechanism by which the suppressor is coupled to a firearm;
Figures 9A-9C are cutaway top views sequentially illustrating first and second parts of the locking mechanism being connected together; and
Figures 10 and 11 is a sectional perspective views of a suppressor according to an alternate embodiment of the invention.

Embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which various embodiments, although not the only possible embodiments, of the invention are shown.

DETAILED DESCRIPTION

In general terms, embodiments of the invention as illustrated in the Figures relate to a suppressor 10 for use with a firearm 12.
With reference to Figures 1 to 4, the suppressor 10 comprises a tubular body 14 that extends between a proximal end 16 and a distal end 18. The proximal end 16 of the body 14 is configured to facilitate coupling of the suppressor 10 to a barrel of the firearm 12. A central bore 20 extends along the body 14, providing a pathway for a projectile to travel through the suppressor 10. The central bore 20 includes an inlet section 22, located at the proximal end 16 of the body 14, and an outlet section 24, located at the distal end 18 of the body 14. A central section 25 extends between the inlet section 22 and the outlet section 24. A first passageway 26 extends axially along a length of the body 14 and is in fluid communication with the inlet section 22 via a valve 17 disposed towards the proximal end of the bore 20 and the outlet section 24 via a port 19 disposed towards the distal end of the chamber 20. The first passageway 26 provides an escape route for a first flow of expansion gases arising from the firing of the projectile to exit the suppressor 10 whilst bypassing the central section 25 of the bore 20.
In use, with the suppressor 10 coupled to the firearm 12, activation of the firearm 12 results in the projectile entering the bore 20 via the inlet section 22 and travelling linearly along the central section 25 and exiting through the outlet section 24. Meanwhile, expansion gases arising from the firing of the projectile also enter the inlet section 22 of the central bore 20. The first flow of said expansion gases pass from the inlet section 22 to the outlet section 24 via the first passageway 26, with a further flow of the expansion gases forward behind the projectile and flowing along the pathway thereof.
The first passageway 26 has an internal geometry configured to dissipate energy of the first flow of expansion gases. The volume of the sonic boom produced by the expulsion of the expansion gases to atmosphere is directly proportional to the energy of the expansion gases. Accordingly, by reducing the energy level of the combined flow of expansion gases exiting through the outlet section 24, the first passageway 26 serves to reduce the sound levels associated with the firing of the projectile from the firearm.
The expansion gases thus have at least two escape routes from the chamber, that is (i) via the first passageway 26; and (ii) through the central section 25 of the bore 20, in the wake of the projectile. By "splitting" the flow of the expansion gases in this way, the level of sound deadening performance of the suppressor is increased without requiring increased size or length of the suppressor itself. Furthermore, because the first passageway 26 is separate from the pathway of the projectile through the central section 25, the travel of the projectile through the suppressor is not inhibited or limited by the geometry of the first passageway 26.
This dual-flow approach (i.e. the expansion gases have more than one escape route to flow through the suppressor 10) helps to reduce back-pressure that is a common drawback of existing suppressor designs.
In this description, the term "firearm" refers to a device that uses the expansion of a gas to propel a projectile at high velocity towards a target. The gas may be created through a chemical process, for example ignition of a combustible material such as gun powder. The expansion of such gas may occur because of increasing temperature thereof, causing the gas to expand rapidly to an area of lower pressure (i.e. along the barrel of the firearm towards atmosphere). Alternatively, the gas may be a compressed gas such as compressed air, with the expansion of such gas being activated via mechanical means such as opening of valves and the like. Whilst the description refers, in main, to use of the suppressor 10 for reducing the sound associated with firing of a firearm, it is understood that the suppressor 10 is not limited to use with firearms. For example, the broad inventive concept of the suppressor 10 is equally applicable for use in other industries where it is desirable to control the expulsion of expanding gases from an outlet of devices. For example, the suppressor 10 can be modified for use in controlling the release of water vapor from a pressure relief valve of a steam engine and/or controlling the exhaust of chemical gases from a combustion engine.
Turning now to Figure 1, an exemplary embodiment of the suppressor 10 is shown. The inlet section 22 is located at the proximal end 16 of the bore 20. The inlet section 22 includes an end wall 30, with the valve 17 being located within the end wall 30 to provide fluid communication between the inlet section 22 and the passageway 26, with the valve 17 serving as an exit point for the first flow of gases to pass out of the inlet section 22 and into the first passageway 26. The outlet section 24 is located at the proximal end 18 of the bore 20. The outlet section includes a port 19 being located within a sidewall thereof, the port 19 providing fluid communication between the first passageway 26 and the outlet section 24, with the port 19 serving as a re-entry point for the first gas flow into the chamber 20. The outlet section 24 includes an end wall 32 disposed at the proximal end 18 of the body 14. The end wall 32 includes at least one orifice 33 providing means for the projectile and for the first flow of expansion gases to exit the outlet section 24. With reference to the illustrated embodiment best shown in Figure 4, the outlet section 24 includes a central orifice 33a for the projectile and a plurality of perimeter orifices 33b through which the expansion gases exit the suppressor 10.
A plurality of baffles 28 divide the central section 25 into a plurality of sub-chambers 31. Depending on the number of baffles 28, any number of sub chambers 31 may be distributed between the inlet section 22 and the outlet section 24. In the illustrated embodiment, there are six intermediate sub chambers 31A-31F disposed between the inlet section and outlet section 22, 24. It is contemplated that one or both of the inlet section 122 and outlet section 124 can also include one or more baffles 28.
Each baffle 28 includes an opening 34 to allow passage of the projectile therethrough. The baffles 28 a frustoconically shaped, being directed towards the proximal end 16 of the body 14. The shape of the baffles 28 facilitates the scavenging of expansion gases from the projectile as it travels along the central section 25. In this way, the energy of a third flow of expansion gases, being the expansion gases travelling through the central section in the wake of the projectile, is also reduced. The number of baffles 28 is dependent on the level of sound reduction required, and the calibre of firearm being used. The higher the number of baffles, the higher the dampening effect produced, with the sound waves bouncing off more surfaces thereof. The shape and geometry of the baffles 28 will be described in more detail later, in reference to Figures 5 and 6.
In use, when a projectile is fired from a firearm 12 to which the suppressor 10 is coupled, expansion gases arising from the firing enter the bore 20 and into the inlet section 22. It is these expansion gases that propel the projectile through the bore 20 of the suppressor 10. It is necessary to expel these gases as quickly and possible so as not to impede the escape velocity and/or direction of the projectile, and to reduce any back pressure to the piston action of the firearm 12 that would be felt by the operator. As described above, suppressor 10 facilitates this by way of providing multiple escape routes for the expansion gases to travel through and exit from the body 14, with the first flow of expansion gases exiting via first passageway 26 and a second flow of expansion gases existing via second passageway 36.
The first passageway 26 is provided as a capillary tube that extends axially along a perimeter of the tubular body 14, linking together the inlet section 22 and outlet section 24 and providing fluid communication therebetween. In this manner, the first passageway 26 provides an escape route or path for the first flow of expansion gases to travel between the inlet 22 and outlet 24 section of the suppressor 10, bypassing the central section 25 that provides part of the pathway taken by the projectile (and the third flow of expansion gases). Put differently, the first passageway 26 provides means for the first flow of expansion gases to bypass the intermediate sub chambers 31 and baffles 28 disposed between the inlet section 22 and outlet section 24 of the bore 20. It is understood that the first passageway 26 may be one of several first passageways 26 disposed around a circumference of the body 14 (see, for example, Figures 3 and 4).
Turning now to Figure 2, the suppressor 10 also includes a second passageway 36. The second passageway 36 is separate from the first passageway 26. In the illustrated embodiment, the second passageway 36 branches off from the inlet section 22, and thus is in fluid communication therewith. It is understood, however, that in alternate embodiments the second passageway may be in fluid communication with any of the sub-chambers 31 disposed along the central section 25. The second passageway 36 extends axially along a perimeter of the tubular body 14 to a secondary orifice 38. The secondary orifice 38 is disposed at the distal end 18 of the body 14 and is separate from the orifice 33 of the outlet section 24 through which the projectile and first and second exhaust flows exit the suppressor 10. Put differently, the secondary orifice 38 is fluidly isolated from the outlet section 24. Accordingly, the second passageway 36 provides an escape route or path for the second flow of expansion gases to travel through the suppressor 10 that bypasses the outlet section 24. In this way, the second flow of expansion gases does not mix or otherwise combine with the first or third flows of expansion gases exiting the suppressor 10 or interfere with the travel of the projectile through the outlet section 24.
The position of the secondary orifice 38 at the distal end 18 of the body 14 is such that the second flow of gases is directed away from the operator and thereby lessens the gassing effect that rapid fire has in the field by overloading the air space around the operator. This is to be contrasted with standard muzzle brakes and suppressors where exhaust gases are blown sideways and may quickly returns to the operator's face and breathing intake. Furthermore, by angling the secondary orifice or orifices 36 outwardly, the sound signature of the suppressor 10 can be disguised, making it difficult to isolate or locate the position from which the firearm 12 was fired. It is understood that the second passageway 34 may be one of several second passageways 36 disposed around a circumference of the body 14 (see, for example, Figures 3 and 4). Another benefit of the secondary orifice or orifices 38 is that chemicals and/or fumes associated with the firing of the projectile (i.e. from the propellant) are exhausted in a direction away from the operator. This is advantageous, for it enables multiple rounds to be discharged by the operator from a single, stationary position, without needing to move away from their current position for cleaner air.
The first passageway(s) 26 and/or second passageway(s) 36 may protrude from the outside of the tubular body 14. This is most clearly shown in Figures 3 and 4. An advantage of the passageways 26, 36 protruding from the side of the otherwise tubular suppressor body 14 is increased grip in the field for wet hands reducing slippage, and to more easily facilitate fast removal of the suppressor 10 from the firearm 12.
Whilst not shown in the illustrated embodiments, it is to be understood that the suppressor 10 can include additional supplementary passageways extending between respective sub-chambers 31 of the central section 25. Such supplementary passageways can provide additional escape routes/flow paths for additional, separate, flows of the expanding gases to pass through the suppressor body 14 whilst bypassing at least one of the baffles 28 and/or outlet section 24.
The flow of expansion gases through the suppressor 10 will now be described in detail with particular reference to Figures 5 and 6. As a projectile is fired from the barrel of firearm 12, it is propelled by the flow of expanding gasses, with both the projectile and trailing flow of gases entering the inlet section 22 of the bore 20. The expanding gas then has three escape routes, with the first flow passing through the first passageway 26 and bypassing the central section 25, the second flow passing through the second passageway and bypassing the outlet section 24, and a remaining flow advancing along the central section 20, trailing behind the projectile. Dealing initially with the first flow of expansion gases. As the expansion gases enter through the inlet section 22, a first portion of the gases are directed through valve or valves 17 within end wall 30 of the inlet section 22. It is this portion of expansion gases which form the first flow of expansion gases. disposed at the proximal end of the tubular body 14. The end wall 30 is disposed at the proximal end of the tubular body 14 and is tapered to function as a guide to ensure alignment of the suppressor 10 with the barrel 12 of the firearm.
The valve or valves 17 are holes that have a teardrop shape that is configured to create a suction or vacuum effect, to draw a portion of the expansion gases entering the sub chamber 30 therethrough. The orifice size or diameter thereof is a further tunable parameter selected by the manufacturer to regulate the comparative flow rate of the first flow of expanding gases with respect to the second and/or third flows. Whilst not illustrated, it is also contemplated that valves 17 may be selectably controllable valves, enabling a manufacturer and/or user of the suppressor to alter the orifice size in-situ depending on the type of projectile and/or firearm 12 being used.
As the first flow of expansion gases passes through valves 17 it is received within a reservoir 44. The reservoir 44 serves as an expansion chamber for the first flow of expansion gases to dissipate energy therefrom. The reservoir 44 enables rapid evacuation of the expansion gases from the chamber 20, reducing back pressure on the firearm. Gases within the reservoir 44 are then transported along the first passageway 26 towards the front or distal end of the suppressor 10, with the first flow re-entering the bore 20 into the outlet section 24 thereof via ports 19. In this way, the first flow of gases is said to bypass the intermediate sub chambers 31 of the central section 25, and the labyrinthine path defined between the baffles 28 and apertures 52 disposed there along.
The size/diameter and number of first passageway(s) 26 is a tunable parameter that is based on the projectile size and escape velocity from the firearm 12. By tunable, what is meant is that the suppressor 10 can be customized to provide improved suppression performance by selecting the size of the first passageway 26 based on the projectile and firearm type it is to be used with. Accordingly, it is understood that a benefit of the present suppressor design is the ability to "tune" the internal geometry to suit a specific caliber and type of projectile.
Moving now to the second flows of expansion gases. As the expansion gases enter the inlet section 22, a second portion thereof are directed through vents 46 within side walls 48 of the bore 20 and into second passageways 36. In the illustrated embodiment the vents 46 are disposed within the inlet section 22 of the bore 20. It is understood, however, that the vents 46 may instead be disposed within any of the sub chambers 31, such that the second passageway 36 instead branches from the central section 25 of the bore 20. It is this portion of expansion gases which form the second flow of expansion gases. Like valves 17, the vents 46 have a teardrop shape that is configured to create a suction or vacuum effect, to draw a portion of the expansion gases within the inlet section 22 therethrough. It is also contemplated that vents 46 may have a different shape. For example, vents 46 may be formed as substantially circular holes. The size/diameter and number of second passageways 36 is a further tunable parameter that is selected based on the projectile and firearm type the suppressor 10 is to be used with. Next to the third flow of expansion gases. Best shown in Figure 6, each of the baffles 28 includes a circular opening 34 that allows passage of the projectile therethrough. The size of the opening 34 is another tunable parameter that is selected based on the size or caliber of the projectile and the rate at which the projectile is fired (i.e. the type of propellant being used). This is because depending on the speed at which the projectile is fired, different levels of clearance are required between the baffles 28 and the projectile passing therethrough.
The openings 34 are defined by upstanding lips or lands 50. The lips 50 have a radius that creates a vacuum or negative pressure region as the projectile passes through the respective opening 34. As such, gases forward behind the projectile are scavenged from the skin of the projectile, the lips 50 generating sufficient slip without interfering with the forward velocity of the projectile through the suppressor. The third flow of expansion gases comprises the gases that are scavenged from the projectile during its passage along the central chamber 20.
Each of the baffles 28 also includes at least one aperture 52. The apertures provide a means for expansion gases to pass between adjacent sub chambers. The size of the apertures 52 is calculated to enable sufficient flow rate of the flow of expansion gases through the central section 25 whilst minimizing the effect on the cycle rate of an automatic firearm. In the illustrated embodiment, the apertures 52 are teardrop shaped. The teardrop shape of the apertures 52 creates a shearing action that forms a small vortex that aids in the dissipation of energy from the gas flow as the flow passes through the aperture. Furthermore, the teardrop shape of the apertures 52 enables the body to be formed through additive manufacturing methods such as 3D printing.
In the illustrated embodiment, each baffle 28 includes six apertures 52, equidistantly arranged around the circumference thereof. In other embodiments, there may be a greater or smaller number of apertures 52. The number of aperture 52 is a tunable parameter selected to enable a sufficient flow rate of expansion gases through the central section 25.
The apertures 52 of subsequent or adjacent baffles 28 are radially offset from one another. This radial offset is aided by having the apertures 52 arranged equidistantly around the circumference of each baffle 28. Alternatively, it is also contemplated that the apertures 52 may be randomly located or distributed around the baffle 28. This deliberate misalignment of apertures 52 creates a labyrinth effect such that the third flow of gases follows a spiral or helix like path along the central section 25, resulting in increased dissipation of energy. In addition, the offset of the apertures 52 results in the deflection the gas flow off many surfaces within the central section 25 providing a further dampening effect. As the third flow of expansion gases passes into the outlet section 24, it is combined with the first flow or flows re-entering the bore 20 via the ports 19, and then exhausted through the orifice 33, the energy of the expansion gases having been dissipated substantially by this point.
Returning briefly to Figure 4, it is understood that the orifice 33 provides an exit to atmosphere for the projectile and expansion gases from the outlet section 24. In the illustrated embodiments, the orifice 33 comprises central round orifice 33a through which the projectile passes, and a plurality of perimeter orifices 33b through which the expansion gases of the first and third gas flows may exit. These perimeter orifices 33b are tear-shaped, similar to apertures 52. The perimeter orifices 33b work to assist in the expulsion of the gases from the forward sub chamber 32 whilst minimising effects on the projectile itself. It is understood, however, that in other embodiments, the perimeter orifices 33b may not be includes such that all of the expansion gases of the first and third may pass through the central orifice 33a.
Turning briefly now to Figure 7, which shows an internal cross section of the body 14. The body includes a cellular lattice-like infill 54. The infill 54 is a 3D printed infill that extends along the interior of the bore 20. The infill 54 is used to aid in the dispersion of gas, flame and sound arising from the firing of the projectile. In particular, as the expansion gases enter into the inlet section 22, the gases are dispersed by the many internal walls and channels produced within the lattice 54. The lattice 54 is made possible by 3D printing, and would not be possible to produce using traditional, subtractive machining methods.
A method by which the suppressor 10 is coupled to the firearm 12 will now be described in reference to Figures 8 and 9A-9C.
As discussed briefly above, the preferred method of manufacture of suppressor 10 is via 3D metal printing. This method of manufacturing is also known as Powder Bed Fusion (PBF), Selective Laser Melt (SLM) and Direct Metal Print (DMP). Briefly, 3D metal printing involves the layering of an amount of metal powder mostly spherical in nature and melting via a laser to a shape and then adding a new layer to the top of this and repeating the process until the component is manufactured. The geometry of the baffles 28, including the shape of the apertures 52, the passageways 26, 36 as well as the lattice infill 54 is only made possible via this manufacturing method, and would not be possible to replicate via conventional subtractive machining methods. Furthermore, the ability to "tune" the performance of the suppressor 10 is dependent, at least in part, on the ability to customize the internal geometry to suit the projectile and firearm 12 being used. Such customization is far easier and more cost-effective using 3D printing than it is in conventional machining methods.
Best shown in Figure 8, the suppressor 10 is couplable to a firearm 12 via a connector mechanism 56. In the illustrated embodiments, the connector mechanism 56 is a two-part mechanism comprising a first component 58 and a second component 60.
The first component 58 is a ring-like member that is directly attached to the proximal end of the body 14. In the illustrated embodiment, the first component 58 is integrally formed with the body 14. It is contemplated, however, that the first component 58 can also be a separate component that is fixedly connectable to the body 14.
The second component 60 is a muzzle-brake that is configured to be attached to the barrel of the firearm 12. The attachment of the second component 60 to the firearm 12 may be via a standard threaded connection, enabling the second component 60 to be selectively fitted to standard firearm 12. The second component 60 includes a head 62 from which a stem 64 extends. The stem 64 has helix-like grooves or flutes 66 arranged therearound. In use, when the suppressor 10 is coupled to the firearm 12 via the connector 56, the grooves 64 impart spiral-like flow onto the expansion gases as the gases enter into the bore 20. It is this rotational flow that assists in directing the first flow of expansion gases through the valve or valves 17 and into the reservoir 44 and the second flow of expansion gasses through the vents 46. As previously described, the remainder of gas and sound will then be scraped or scavenged from the projectile by subsequent baffles 28 along the central section 25. The direction of the helix is dependent on the spiral of rifling in the firearm barrel, so as to keep the projectile and expansion gases rotating in the same direction.
The connector 56 facilitates quick release and attachment of the suppressor 10 to the firearm 12. Specifically, with the second component 58 pre-fitted to the barrel of a selected firearm, the suppressor 10 (to which the first component 58 is fixedly attached) can be quickly and easily installed onto the firearm 12 by way of fitting the first component 58 over the stem 62 of the second component 60, and locking the components together in a simple twisting motion. As such, the connector 56 provides a quick and simple "twist and release" method of installing and uninstalling the suppressor 10 from the firearm 12.
This quick release arrangement is facilitated by way of complimentary locking elements 68 and 70, shown best in Figures 9A-9C. For clarity, the first component 58 is shown separated from the suppressor 10. It is understood, however, that in use the first component 58 is either integrally formed with or fixedly attached to the suppressor body 14. Locking elements 68 are protrusions or fingers that project inwardly into the central bore of the first component 56. Meanwhile, complimentary locking elements 70 are protrusions or fingers that project outwardly from the head of an upper portion of the second component 58. In the illustrated embodiments, there are four locking elements 68 and four locking elements 70, arranged equidistantly around the respective components.
In use, when installing the suppressor 10 onto the firearm 12, the locking elements 68, 70 are aligned in an offset arrangement, shown in Figure 9A. This enables the first component 56 to be slid over the stem 64 of the second component 60, until the first component 56 surrounds the head 62 of the second component 60. At this point, the suppressor body 14 is then rotated, as shown in Figure 10B, such that the locking elements 68,70 are engaged in a partly overlapping arrangement. Further relative rotation between the components 56,58 leads to full engagement as shown in Figure 10C, where the locking elements 68,70 completely overlap one another. As shown, a quarter rotation (i.e. 90 degrees) is all that is required to achieve full engagement.
In other embodiments (not shown), it is contemplated that the suppressor 10 may be directly couplable to the barrel of the firearm 12. In such embodiments, the connector mechanism 56 is provided as a threaded surface, disposed at the proximal end 16 of the suppressor 10. The threaded surface being adapted to engage directly with the barrel of the firearm 12. Such an embodiment may be preferred by certain users such as when fitting the suppressor 10 to sniper rifles.
Turning now to Figures 10 and 11, and alternate embodiment of the invention in the form of suppressor 110 is shown. In this embodiment, the first passageway 126 extends from the first inlet section 122 directly to a secondary orifice 138, whilst the second passageway 136 extends from the inlet section 122 to the outlet section 124. Accordingly, the bypass routes of the first and second flows of expansion gases are effectively reversed when compared to the embodiment shown in Figure 1.
Specifically, the first flow of expanding gasses and sound waves passes from the barrel of the firearm coupled thereto and into the inlet section 122 and expands through valve or valves 117 and into the reservoir 144. The first flow of expanding gases is then transported along the first passageway 126 where energy is dissipated, runs to the front or distal end of the suppressor 110 and is exhausted through secondary orifice 138. Meanwhile, the second passageway 138 takes the second flow of expanding gas from the inlet section 122 and transfers this to the outlet section 138 where it mixes with the third flow of expanding gas and sound waves that trails behind the projectile, having been scavenged by the baffles 128 distributed along the central section 125. The combined second and third flows of expanding gas are then exhausted from the outlet section 124 through the orifice 133, the energy of the expansion gases having been dissipated substantially by this point.
This embodiment is particularly well suited for semi-automatic firearms or rapid-repeat firing of projectiles where there is an increased need for rapid expulsion of expansion gases from the suppressor 110. This is because the first flow of expansion gases is directly exhausted via the secondary outlet 138 and does not follow or affect subsequent projectiles travelling through the outlet section 124. Like suppressor 10, suppressor 110 can be tuned by adjusting the orifice or inside diameter of the first and second passageways 126, 136 to carry different volumes of gas to the secondary orifice 138 and outlet section 124 respectively.
Summarily, it is understood that the suppressor device as described herein provides a simple, and efficient device for reducing the levels of sound associated with the firing of a projectile from a firearm. The multi-flow design facilitated by the passageways provides strong sound suppression performance without affecting the travel of the projectile along its own, separate, pathway. Furthermore, the ability to "tune" the suppressor to suit particular firearms and projectiles provides significant performance advantages over existing designs, such tuning being made possible the passageway design, and assisted by the 3D printing manufacturing method enabling customisation that would otherwise not be possible. The simple twist-lock connection mechanism provides a quick and reliable installation method for installing the suppressor to a firearm.
It will be appreciated by persons skilled in the art that numerous variations and modifications may be made to the above-described embodiments, without departing from the scope of the following claims. The present embodiments are, therefore, to be considered in all respects as illustrative of the scope of protection, and not restrictively.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the example methods and materials are described herein.
It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.
In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

LEGEND

# No.	Name	# No.
10	Suppressor	60	Second Connector Component
12	Firearm	62	Head of Second Connector
14	Suppressor body	64	Stem of Second Connector
16	Proximal End	66	Flutes
17	Valve	68	Locking Elements (1^st Connector)
18	Distal End	70	Locking Elements (2^nd connector)
19	Port
20	Bore
22	Inlet Section of Bore
24	Outlet Section of Bore
25	Central Section of Bore
26	First Passageway(s)
28	Baffle(s)
30	End wall of Inlet Section
31	Intermediate Sub Chamber(s)
32	End wall of Outlet Section
34	Baffle Opening(s)
36	Second Passageway(s)
38	Secondary Orifice(s)
44	Reservoir
46	Vent(s)
48	Side wall
50	Baffle lips
52	Baffle Aperture(s)
54	Lattice infill
56	Connector Mechanism
58	First Connector Component

Claims

A suppressor (10) for a firearm (12), comprising a tubular body (14) couplable to a barrel of the firearm, characterised in that the body includes:
a bore (20) that provides a pathway for a projectile to travel through the suppressor, the bore including an inlet section (22) disposed at a proximal end of the body, a central section (25) and an outlet section (24) disposed at a distal end of the body; and

a first passageway (26) that extends axially along a length of the body and is disposed

externally of the bore and is in fluid communication with the inlet section,
wherein, when the suppressor is coupled to the firearm, expansion gases enter the bore through the inlet section and propel the projectile along the central section and through the outlet section, with a first flow of expansion gases passing from the inlet section into the first passageway before being expelled from the body, with energy from the first flow of expansion gases being dissipated along the first passageway to thereby reduce sound levels associated with the firing of the projectile.
The suppressor of claim 1, characterised in that the first passageway (26) extends between the inlet section (22) and the outlet section (24) such that the first flow of expansion gases bypasses the central section of the bore.
The suppressor of claim 1 or claim 2, characterised in that the outlet section (24) includes an end wall (32) having a central orifice (32a) for the projectile to exit the bore and at least one perimeter orifice (32b) for the first flow of expansion gases to exit the suppressor.
The suppressor of any one of claims 1 to 3, characterised in that the inlet section includes an end wall (30) having a valve (17) providing fluid communication of the first flow of expansion gases between the inlet section and into the first passageway.
The suppressor of any one of claims 1 to 4, characterised in that the body further includes:
a second passageway (36) that extends axially along a length of the body (14) that is disposed externally of the bore (20) and separate from the first passageway (26) and is in fluid communication with the inlet section (22) or the central section (25) of the bore;

wherein, when the suppressor is coupled to the firearm, a second flow of expansion gases pass from the central section and into the second passageway before being expelled from the body, with energy from the second flow of expansion gases being dissipated along the second passageway to thereby reduce sound levels associated with the firing of the projectile.
The suppressor of claim 5, characterised in that the second passageway (36) extends to a secondary orifice (38), the secondary orifice providing a direct exit for the second flow of expansion gases from the suppressor such that the second flow of expansion gases bypasses the outlet section (24).
The suppressor of any one of claims 1 to 6, characterised in that the body (14) further includes a baffle (28) that divides the central section of the bore into a plurality of intermediate sub chambers (31), with the baffle having an opening permitting passage of the projectile therethrough.
The suppressor of claim 7, characterised in that the baffle (28) is frusto-conically shaped and oriented towards the proximal end of the body (14).
The suppressor of claim 7 or 8, characterised in that the baffle (28) includes at least an aperture (52) that provides fluid communication between adjacent sub chambers defined thereby, such that, when the suppressor is coupled to the firearm, a third flow of expansion gases pass between adjacent sub chambers of the central section via the aperture.
The suppressor of any one of claims 7 to 9, characterised in that the baffle (28) is one of a plurality of baffles disposed along a length of the central section of the bore (20), with each of the baffles having at least one aperture (52).
The suppressor of claim 10, characterised in that the one or more apertures (52) of each of the baffles (28) are offset from the apertures of adjacent baffles, such that the third flow of expansion gases passing along the central section must follow a non-linear path thereby dissipating energy and sound levels associated therewith.
The suppressor of any one of claims 1 to 11, characterised in that the body (14) further includes a fluid reservoir (44) located between the inlet section (22) and the first passageway (26).
The suppressor of any one of claims 1 to 12, characterised in that it further comprises a connector mechanism (56) for coupling the body (14) to the barrel of the firearm, wherein the connector mechanism comprises a first component (58) that is integrally formed with, or configured to directly interface with, the tubular body (14) and configured to engage with a separate second component (60), the second component being configured to directly interface with the barrel of the firearm.
The suppressor of claim 13, characterised in that the first and second components (58, 60) each comprise complimentary locking elements (68, 70) to rotationally secure said the body (14) to the barrel of the firearm.
The suppressor of any one of claims 1 to 14, characterised in that it further comprises a lattice-like (54) infill that is disposed within the tubular body (14) and dissipates energy from the expansion gasses entering into the suppressor.