U.S. patent application number 13/839977 was filed with the patent office on 2014-09-18 for combination flash and acoustic suppression system and method.
The applicant listed for this patent is Andrew T. Anderson, William C. Moss. Invention is credited to Andrew T. Anderson, William C. Moss.
Application Number | 20140262602 13/839977 |
Document ID | / |
Family ID | 51522502 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140262602 |
Kind Code |
A1 |
Moss; William C. ; et
al. |
September 18, 2014 |
COMBINATION FLASH AND ACOUSTIC SUPPRESSION SYSTEM AND METHOD
Abstract
A combination acoustic and flash suppression system and method
for use with a weapon that fires a bullet. A noise suppressor
module or section of the system is adapted to be connected to a
distal end of a barrel of the weapon, and a flash suppressor module
or section of the system is adapted to be connected to the outlet
end of the noise suppressor module, so that the downstream position
of the flash suppressor module relative to the noise suppressor
module helps to disrupt a Mach disk from forming at a downstream
location from the discharge port when a bullet fired from the
barrel exits from the discharge port so as to suppress both flash
and noise.
Inventors: |
Moss; William C.; (San
Mateo, CA) ; Anderson; Andrew T.; (Livermore,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Moss; William C.
Anderson; Andrew T. |
San Mateo
Livermore |
CA
CA |
US
US |
|
|
Family ID: |
51522502 |
Appl. No.: |
13/839977 |
Filed: |
March 15, 2013 |
Current U.S.
Class: |
181/211 ;
181/296 |
Current CPC
Class: |
F41A 21/30 20130101;
F41A 21/34 20130101 |
Class at
Publication: |
181/211 ;
181/296 |
International
Class: |
F41A 21/30 20060101
F41A021/30; F41A 21/34 20060101 F41A021/34 |
Goverment Interests
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] The United States Government has rights in this invention
pursuant to Contract No. DE-AC52-07NA27344 between the United
States Department of Energy and Lawrence Livermore National
Security, LLC for the operation of Lawrence Livermore National
Laboratory.
Claims
1. A combination acoustic and flash suppression system for use with
a weapon that fires a bullet, the system comprising: a noise
suppressor module having a body portion with an inlet end adapted
to be connected to a distal end of a barrel of the weapon, an
outlet end, and a bore extending between the inlet and outlet ends
concentric with a bore axis of the barrel when the noise suppressor
module is connected to the distal end of the barrel; and a flash
suppressor module having a body portion with an inlet end adapted
to be connected to the outlet end of the noise suppressor module,
an outlet end with a discharge port, a bore in communication with
the discharge port extending between the inlet and outlet ends of
the flash suppressor module concentric with the bore axis of the
barrel when connected to the outlet end of the noise suppressor
module, and sidewall openings communicating with the bore, whereby
the downstream position of the flash suppressor module relative to
the noise suppressor module helps to disrupt a Mach disk from
forming at a downstream location from the discharge port when a
bullet fired from the barrel exits from the discharge port.
2. A noise and flash suppressor for use with a weapon that fires a
bullet, the suppressor comprising a body having: a noise suppressor
section including an inlet end adapted to be connected to a distal
end of a barrel of the weapon; a flash suppressor section including
sidewall openings and an outlet end with a discharge port, and
located downstream of the noise suppressor section when the inlet
end is connected to the distal end of the barrel; and a bore
extending between the inlet and outlet ends concentric with a bore
axis of the barrel when the inlet end is connected to the distal
end of the barrel, and in communication with the discharge port and
the sidewall openings of the flash suppressor section, whereby the
downstream position of the flash suppressor section relative to the
noise suppressor section helps to disrupt a Mach disk from forming
at a downstream location from the discharge port when a bullet
fired from the barrel exits from the discharge port.
3. A method of suppressing noise and flash from a weapon that fires
a bullet, the flash and noise being generated by expanding
propellant gasses exiting from a distal end of a barrel of the
weapon as the bullet is fired from the weapon, the method
comprising: providing a noise suppressor module having a body
portion with an inlet end adapted to be connected to a distal end
of a barrel of the weapon, an outlet end, and a bore extending
between the inlet and outlet ends concentric with a bore axis of
the barrel when the noise suppressor module is connected to the
distal end of the barrel; providing a flash suppressor module
having a body portion with an inlet end adapted to be connected to
the outlet end of the noise suppressor module, an outlet end with a
discharge port, a bore in communication with the discharge port
extending between the inlet and outlet ends of the flash suppressor
module concentric with the bore axis of the barrel when connected
to the outlet end of the noise suppressor module, and sidewall
openings communicating with the bore; securing the inlet end of the
noise suppressor module to the distal end of the barrel; and
securing the inlet end of flash suppressor module to the outlet end
of the noise suppressor, whereby the downstream position of the
flash suppressor module relative to the noise suppressor module
helps to disrupt a Mach disk from forming at a downstream location
from the discharge port when a bullet fired from the barrel exits
from the discharge port.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to U.S. patent application Ser.
No. 13/764,380, filed Feb. 11, 2013, entitled "SYSTEM AND METHOD
FOR MULTI-STAGE BYPASS, LOW OPERATING TEMPERATURE SUPPRESSOR FOR
AUTOMATIC WEAPONS" which is incorporated herein by reference in its
entirety.
FIELD OF THE INVENTION
[0003] The present disclosure relates to noise and flash
suppressors, and more particularly to a combined noise and flash
suppression system and method for suppressing both acoustic and
flash signatures from the muzzle of a weapon by Mach disk
disruption.
BACKGROUND
[0004] The statements in this section merely provide background
information related to the present disclosure and may not
constitute prior art.
[0005] Firearms typically produce noise and flash. Flash is
typically reduced by attaching a flash suppressor (aka "flash
hider") on the end of the muzzle, and many weapons are routinely
used with such flash suppressors. For example, most military
firearms (excluding pistols) are equipped with roughly cylindrical
devices that attach to the end of the muzzle that have slots, holes
or other form of vent openings to partially vent the escaping
gases, and which provide flash reduction relative to a bare muzzle.
However, the physics of flash generation and reduction has not been
well understood, and the merits of variations in design between
competing manufacturers is not clear. Furthermore, when it is
desirable and/or required to also lessen the noise from a weapon,
an acoustic or noise suppressor (aka "silencer", and typically
large substantially cylindrically-shaped can) is attached to the
end of the weapon, usually attaching over the entirety of the
existing flash suppressor if the weapon has a flash suppressor
already attached.
[0006] Conventional noise suppressors typically perform acoustic
suppression using internal baffles and chambers that both trap and
delay the propellant gasses from exiting the barrel of the weapon.
Such previous noise suppressor designs generally operate by
expanding and cooling the hot expanding propellant gasses in the
internal chambers of the suppressor, then delaying the release of
the expanding propellant gasses, which transfers heat to the
suppressor. The additional time that the propellant spends in the
suppressor before being discharged to the ambient atmosphere
results in a reduced acoustic signature. Other methods for
suppressing/reducing noise may include, for example, using sinuous
flow paths to delay the exit of propellant gases from the discharge
port and reduce exit pressures, using sound insulating material in
the sidewalls, etc. In any case, while such noise suppressors do
operate to reduce noise levels, they do not silence the weapon
completely. For example, noise reduction is at best .about.35 db,
at a few meters from the muzzle, compared to an unsuppressed noise
level that can be as high as .about.180 db. Moreover, attaching a
noise suppressor completely over the flash suppressor can defeat
the functioning of the flash suppressor so that flash re-appears at
the discharge port of the noise suppressor.
SUMMARY
[0007] One aspect of the present invention includes a combination
acoustic and flash suppression system for use with a weapon that
fires a bullet, the system comprising: a noise suppressor module
having a body portion with an inlet end adapted to be connected to
a distal end of a barrel of the weapon, an outlet end, and a bore
extending between the inlet and outlet ends concentric with a bore
axis of the barrel when the noise suppressor module is connected to
the distal end of the barrel; and a flash suppressor module having
a body portion with an inlet end adapted to be connected to the
outlet end of the noise suppressor module, an outlet end with a
discharge port, a bore in communication with the discharge port
extending between the inlet and outlet ends of the flash suppressor
module concentric with the bore axis of the barrel when connected
to the outlet end of the noise suppressor module, and sidewall
openings communicating with the bore, whereby the downstream
position of the flash suppressor module relative to the noise
suppressor module helps to disrupt a Mach disk from forming at a
downstream location from the discharge port when a bullet fired
from the barrel exits from the discharge port.
[0008] Another aspect of the present invention includes a noise and
flash suppressor for use with a weapon that fires a bullet, the
suppressor comprising a body having: a noise suppressor section
including an inlet end adapted to be connected to a distal end of a
barrel of the weapon; a flash suppressor section including sidewall
openings and an outlet end with a discharge port, and located
downstream of the noise suppressor section when the inlet end is
connected to the distal end of the barrel; and a bore extending
between the inlet and outlet ends concentric with a bore axis of
the barrel when the inlet end is connected to the distal end of the
barrel, and in communication with the discharge port and the
sidewall openings of the flash suppressor section, whereby the
downstream position of the flash suppressor section relative to the
noise suppressor section helps to disrupt a Mach disk from forming
at a downstream location from the discharge port when a bullet
fired from the barrel exits from the discharge port.
[0009] Another aspect of the present invention includes a method of
suppressing noise and flash from a weapon that fires a bullet, the
flash and noise being generated by expanding propellant gasses
exiting from a distal end of a barrel of the weapon as the bullet
is fired from the weapon, the method comprising: providing a noise
suppressor module having a body portion with an inlet end adapted
to be connected to a distal end of a barrel of the weapon, an
outlet end, and a bore extending between the inlet and outlet ends
concentric with a bore axis of the barrel when the noise suppressor
module is connected to the distal end of the barrel; providing a
flash suppressor module having a body portion with an inlet end
adapted to be connected to the outlet end of the noise suppressor
module, an outlet end with a discharge port, a bore in
communication with the discharge port extending between the inlet
and outlet ends of the flash suppressor module concentric with the
bore axis of the barrel when connected to the outlet end of the
noise suppressor module, and sidewall openings communicating with
the bore; securing the inlet end of the noise suppressor module to
the distal end of the barrel; and securing the inlet end of flash
suppressor module to the outlet end of the noise suppressor,
whereby the downstream position of the flash suppressor module
relative to the noise suppressor module helps to disrupt a Mach
disk from forming at a downstream location from the discharge port
when a bullet fired from the barrel exits from the discharge
port.
[0010] Generally, the present invention involves a combination
noise and flash suppression system configured to provide both
acoustic and flash suppression by relatively positioning a flash
suppressor module or section of the system downstream of a noise
suppressor module or section of the system so as to be adjacent a
discharge port where a bullet (or other projectile) exits the
weapon. In one example embodiment, a noise suppressor module or
component of the system is adapted to be attachable to a muzzle
(i.e. a distal end of a barrel) of a weapon, and a separate flash
suppressor module or component of the system is adapted to be
attachable to an exit end of the noise suppressor component. In an
alternative embodiment, a noise suppressor section and an adjacent
flash suppression section may be integrated together and provided
as part of a single-bodied suppressor unit, with the unit
suppressor being connectable to the muzzle so that the flash
suppression section is positioned downstream of the noise
suppression section.
[0011] The advantage of positioning the flash suppressor module or
section downstream of the noise suppressor module or section and
adjacent the discharge port is that the vent ports of the flash
hider can operate to cause disruption of the shock front, also
known as "Mach disk," that forms when the supersonic flow of the
expanding propellant gases exits the muzzle at supersonic
velocities, and which is often observed when shooting a bare muzzle
weapon (i.e., with no suppressor or flash hider attached). It is
appreciated that the "Mach disk" defines the location where the
supersonic flow slows abruptly due to its interaction with the
surrounding pressure field, and can be characterized as a "shock"
normal to the flow direction (which tends to form at about 10-15
bore diameters from the bare muzzle, or at about 9 cm for a 7.62 mm
caliber weapon). Such an abrupt decrease in flow velocity at the
Mach disk creates a large compression and a very large increase in
temperature of the hot propellant gases, such that the gases are
hot enough to emit light and cause a "flash." Thus, by positioning
the flash suppressor module or section downstream of the noise
suppressor module or section to disrupt the Mach disk, there cannot
be a large temperature rise in the downstream flow, and both noise
and flash can be mitigated. Disruption of the Mach disk may be
caused by the weakening of the flow due to gas venting through the
ports of the flash hider or by physical disruption of the Mach disk
due to the end of the flash hider being located in the region where
the Mach disk would otherwise form.
[0012] FIGS. 2-4 show a progressive time sequence at approximately
0.25 ms intervals of a comparative computer simulation of a 25 mm
bullet 71 shot from both a bare muzzle 70 without a flash hider,
and a muzzle 70' with a flash hider 80 (scaled from a 50 caliber
Vortex M2E2 flash eliminator) attached to it. Only hot air with
temperature in excess of 800K is shown. Beginning at FIG. 2, hot
propellant (not shown) is contained behind the bullet 71 which is
shown positioned still within the muzzle. As shown by hot air 81,
82, and 83 in FIGS. 2-4, at progressively further downstream
positions from the bare muzzle 70, there is an increase in
temperature observed (due to creation of Mach disk) when a flash
hider is not utilized. In contrast, the muzzle 70' with flash hider
80 shows hot air only at the flash hider but not otherwise observed
at downstream positions from the flash hider. This simulation shows
that the flash suppressor disrupts the Mach disk, so that there is
no hot air present to initiate combustion of the propellant
gases.
[0013] FIGS. 5A and 5B show normal and enlarged views,
respectively, of two simulations of a bullet shot from a bare
muzzle (shown at bottom half of figures) and a muzzle with a flash
hider (shown at top half of figures). Disruption of the Mach disk
can be readily seen in the enlarged view of FIG. 5B, with a
substantial temperature difference. It is notable that inaccurate
heat capacities (which have no effect on the simulation, only on
the temperature scale of the visualization) underpredict the actual
temperatures. FIG. 6 shows the same image as FIG. 5 but .about.1.5
ms later in time. There is no Mach disk present (hence no
temperature rise) in the top half of the figure associated with the
muzzle with flash hider, but a pronounced one in the bottom half of
the figure associated with the bare muzzle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The drawings described herein are for illustration purposes
only and are not intended to limit the scope of the present
disclosure in any way
[0015] FIG. 1 is a longitudinal cross-sectional view of an example
embodiment of the combination flash and acoustic suppression system
of the present invention.
[0016] FIGS. 2-4 show a progressive time sequence in approximately
0.25 ms intervals, of two simulations of a bullet shot from a bare
muzzle and a muzzle with a flash hider.
[0017] FIGS. 5A and 5B show normal and enlarged cross-sectional
views, respectively, of two simulations of a bullet shot from a
bare muzzle (shown at bottom half of figures) and a muzzle with a
flash hider (shown at top half of figures).
[0018] FIG. 6 is a cross sectional view of the two simulations
following FIGS. 5A and 5B at .about.1.5 ms later in time.
DETAILED DESCRIPTION
[0019] The following description is merely exemplary in nature and
is not intended to limit the present disclosure, application, or
uses. It should be understood that throughout the drawings,
corresponding reference numerals indicate like or corresponding
parts and features.
[0020] Turning now to the drawings, FIG. 1 shows a combination
flash and acoustic suppression system in accordance with one
embodiment of the present disclosure, generally indicated at 40,
and attached to a distal end 11 of a barrel 10 of a weapon. The
weapon may be various types of firearms having a barrel for
shooting a projectile (e.g. bullet) therefrom, such as for example,
handguns, machine guns, semi-automatic weapons, etc. And the system
40 may be made from any material that is suitable for withstanding
the high temperatures that are encountered from firing ammunition
from a weapon. In one embodiment the suppressor is made from steel,
but other materials, for example, titanium, Inconel or any other
suitable high strength material could be used as well.
[0021] The system 40 is shown having two modules or components,
namely a noise suppressor module indicated at 50, and a flash
suppressor module indicated at 60. Dashed line 12 represents an
axial center of the bore of the barrel 10 (i.e., the "bore axis")
as well as the axial center of a bore 53 of the noise suppressor
module 50 and the bore 63 of the flash suppressor module 60. As
drawn in FIG. 1, during firing of a cartridge from the weapon, a
bullet from the cartridge will travel from left to right, first
through the noise suppressor module, component, or section 50, then
through the flash suppressor module, component, or section 60. The
two modules are shown as two separate units which may be connected
together into the system 40 of the present invention. It is
appreciated that the two units may in the alternative be integrally
formed as a single unit so long as the noise suppressor section of
the unit system is adapted to be connected to the barrel with the
flash suppressor section positioned downstream of the noise
suppressor section.
[0022] The noise suppressor component 50 has a body with an inlet
end 51, an opposite outlet end 52, and a bore 53 extending between
the inlet and outlet ends concentric with a bore axis 12 of the
barrel 10 when the noise suppressor module 50 is connected to the
distal end 11 of the barrel. In this regard, the inlet end 51 is
adapted to be connected to a distal end of a barrel of the weapon,
such as by a conventional threaded connection or by any other
suitable method or means of attachment, such as for example a quick
connect/disconnect mechanism. In particular, FIG. 1 shows the bore
53 at the inlet end 51 having internal threads adapted to receive
external threads on the distal end 11 of the barrel 10, as is well
known in the firearms industry. Furthermore, the noise suppressor
module may be particularly constructed with an internal
construction designed to attenuate noise, such as for example,
using baffles such as shown at 54 projecting orthogonal relative to
the dashed line 12. The baffles 54 may be spaced apart from one
another along a portion of the length of the noise suppressor
portion 50, but do not necessarily need to have the same radial
extent (i.e., dimension) as depicted in FIG. 1. The baffles 54
impede the flow of the expanding propellant gases out from the
noise suppressor module 50 and slow the buildup of pressure therein
and through the flash suppressor module 60, to reduce the peak
pressure, pressure gradients, and temperature of the expanding
propellant gasses when they initially exit the barrel 10. Other
alternatives for effecting noise reduction may include, for
example, using sinuous flow paths to delay the exit of propellant
gases from the discharge port and reduce exit pressures as
described in U.S. patent application Ser. No. 13/764,380, filed
Feb. 11, 2013, entitled "SYSTEM AND METHOD FOR MULTI-STAGE BYPASS,
LOW OPERATING TEMPERATURE SUPPRESSOR FOR AUTOMATIC WEAPONS" for
disrupting the Mach Disk, using sound insulating material in the
sidewalls, etc.
[0023] The flash suppressor module 60 is shown having a body with
an inlet end 61 adapted to be connected to the outlet end 52 of the
noise suppressor portion, an outlet end 62 with a discharge port
65, and a bore 63 in communication with the discharge port 65 and
extending between the inlet and outlet ends 61, 62 of the flash
suppressor module concentric with the bore axis 12 of the barrel 10
when connected to the outlet end 52 of the noise suppressor module
50. The flash suppressor module 60 is also shown having slots 64
(of a four prong flash hider device) communicating with the bore
63, and providing additional exit points for the propellant gases
to exit the flash suppressor prior to the discharge port 65, which
helps to reduce the quantity, pressure, and temperature of the
propellant gases exiting from the discharge port, to thereby reduce
the likelihood of flash production. It is appreciated that other
forms, shapes, sizes of sidewall openings may be used in the
alternative, such as for example vent holes, ports, etc. In this
manner, the downstream position of the flash suppressor module 60
relative to the noise suppressor module 50 helps to disrupt a Mach
disk from forming at a downstream location from the discharge port
65 when a bullet fired from the barrel 10 exits from the discharge
port, as described in the Summary.
[0024] While various embodiments have been described, those skilled
in the art will recognize modifications or variations which might
be made without departing from the present disclosure. The examples
illustrate the various embodiments and are not intended to limit
the present disclosure. Therefore, the description and claims
should be interpreted liberally with only such limitation as is
necessary in view of the pertinent prior art.
* * * * *