U.S. patent application number 15/572650 was filed with the patent office on 2018-10-04 for diversionary device.
This patent application is currently assigned to AMTEC Less Lethal Systems, Inc.. The applicant listed for this patent is AMTEC LESS LETHAL SYSTEMS, INC.. Invention is credited to Duncan THOMAS.
Application Number | 20180283836 15/572650 |
Document ID | / |
Family ID | 53784818 |
Filed Date | 2018-10-04 |
United States Patent
Application |
20180283836 |
Kind Code |
A1 |
THOMAS; Duncan |
October 4, 2018 |
Diversionary Device
Abstract
In a multi-burst diversionary device (10) containing a number of
pyrotechnic cartridges (22) arranged in a series and a firing
arrangement (14), a first of the cartridges is ignited by the
firing arrangement, the remaining cartridges are each ignited
sequentially by the flash of pressure and heat (hot gasses)
produced when a previous cartridge in the series deflagrates. The
device has a housing (12) defining a number of compartments (20) in
which the cartridges are received. The housing defines flow paths
interconnecting the compartments in series and the first
compartment with the firing arrangement. Each compartment is also
fluidly connected with atmosphere.
Inventors: |
THOMAS; Duncan; (Birmingham,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AMTEC LESS LETHAL SYSTEMS, INC. |
Perry |
FL |
US |
|
|
Assignee: |
AMTEC Less Lethal Systems,
Inc.
Perry
FL
|
Family ID: |
53784818 |
Appl. No.: |
15/572650 |
Filed: |
June 14, 2016 |
PCT Filed: |
June 14, 2016 |
PCT NO: |
PCT/GB2016/051756 |
371 Date: |
November 8, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F42B 8/26 20130101; F42B
12/42 20130101; F42B 12/208 20130101; F42B 27/00 20130101 |
International
Class: |
F42B 12/20 20060101
F42B012/20; F42B 8/26 20060101 F42B008/26; F42B 12/42 20060101
F42B012/42; F42B 27/00 20060101 F42B027/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 16, 2015 |
GB |
1510556.2 |
Claims
1. A diversionary device comprising: a housing holding a plurality
pyrotechnic cartridges arranged in series, each cartridge having a
combustible fuze and a pyrotechnic charge; a firing arrangement
including a primer charge; and the housing defining a first flow
path configured to channel hot gasses (flash) given off by the
primer charge onto the fuze of a first cartridge in the series
only, the housing defining further flow paths configured to channel
a portion of the hot gas (flash) produced on deflagration of the
pyrotechnic charge in each of the cartridges upstream from a last
cartridge in the series onto the fuze of an adjacent downstream
cartridge.
2. A diversionary device as claimed in claim 1, wherein the housing
defines a plurality of compartments, each compartment for holding a
respective one of the pyrotechnic cartridges.
3. A diversionary device as claimed in claim 2, wherein each
compartment has a fuze end and a charge end, each cartridge being
located in its respective compartment with its fuze at the fuze end
of the compartment and the further flow paths being configured to
connect a fuze end of each compartment with the charge end of the
preceding upstream compartment in the series.
4. A diversionary device as claimed in claim 3, wherein each
compartment comprises a chamber defined within the housing, the
further flow paths connecting the chambers sequentially in series,
a fuze end region of each chamber in the series downstream from the
first chamber being connected by means of a flow path with a charge
end region of the preceding upstream chamber in the series.
5. A diversionary device as claimed in claim 1, wherein, for each
pair of adjacent chambers in the series, the housing defines a flow
path which interconnects the charge end region of the upstream
chamber in the pair to the fuze end region of the downstream
chamber in the pair and which also connects both end regions to
atmosphere.
6. A diversionary device as claimed in claim 3, wherein the housing
comprises a main body portion having a central axis with
compartments disposed in the main body portion about the axis, the
compartments arranged so that the charge end of each compartment is
located adjacent the fuze end of the next downstream chamber in the
series; the housing also comprising a first end cap and a second
end cap, the end caps being releasably mountable to opposite ends
of the main body portion, the end caps defining the further flow
paths interconnecting compartments sequentially in series.
7. A diversionary device as claimed in claim 6, wherein the first
end cap comprises a mounting for receiving a firing mechanism and
defines at least part of the first flow path for fluidly connecting
the primer charge with a fuze end of a first one of the
compartments in the series.
8. A diversionary device as claimed in claim 1, wherein the
compartments are disposed generally in a common plane.
9. A diversionary device as claimed in claim, wherein the housing
comprises a main body in which the compartments are located and a
firing mechanism releasably mountable to the main body, the main
body having two parts releasably attachable to one another, the
chambers and fluid flow paths being defined by corresponding
formations in mating faces of the two parts.
10. A diversionary device as claimed in claim 1, wherein the
compartments are arranged axially in-line.
11. A diversionary device as claimed in claim 10, wherein the
housing is elongate having an upstream end and a downstream end,
the firing arrangement being located at the upstream end.
12. A diversionary device as claimed in claim 11, wherein the
housing comprises at least two tubular housing members including a
first tubular housing member having an end cap at an upstream end
incorporating or to which is mounted the firing mechanism and a
final tubular housing member having a second end cap at a
downstream end; each pair of adjacent tubular housing members being
releasably interconnected by an adaptor.
13. A diversionary device as claimed in claim 12, wherein the first
end cap and each of the adaptors define at a downstream end a
recess which opens into the interior the adjacent downstream
tubular housing member, the recess being dimensioned to receive a
fuze end of a respective one of the pyrotechnic cartridges.
14. A diversionary device as claimed in claim 13, wherein each
adaptor defines at an upstream end a further recess which opens
into the interior of the adjacent upstream tubular housing member
for receiving a charge end of a respective one of the pyrotechnic
cartridges; each adaptor farther defining a flow path fluidly
connecting the recess at the downstream end and the further recess
at the upstream end.
15. A diversionary device as claimed in claim 14, wherein the
adaptor flow path comprises at least one flow passage which is
offset from the axial centreline of the recess.
16. A multi-burst diversionary device comprising: a housing holding
a plurality of pyrotechnic cartridges and a firing arrangement
operatively connected with a first one of the cartridges to ignite
said first one of the cartridges only, the device comprising
formations for directing on to each of the remaining cartridges a
portion of the hot gas given off on deflagration another of the
cartridges.
17. A method of operating a multi-burst diversionary device
comprising a plurality of pyrotechnic cartridges each cartridge
having a combustible fuze and a pyrotechnic charge, the method
comprising: (a) using a primer charge to ignite the fuze of a first
one of the cartridges; and (b) sequentially igniting the fuzes of
the remaining pyrotechnic cartridges in series by directing a
portion of the hot gas produced when each cartridge deflagrates
onto the fuze of another of the cartridges.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This is a U.S. National Stage filing made pursuant to 35
U.S.C. .sctn. 371. This U.S. application claims the benefit of a
prior Patent Cooperation Treaty filing that was assigned
Application No. PCT/GB2016/051756. The earliest priority date in
the parent application is Jun. 16, 2015
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
MICROFICHE APPENDIX
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The present invention relates to a multi-burst diversionary
device and to a method of igniting the fuzes of a plurality of
pyrotechnic cartridges in a multi-burst diversionary device.
[0006] 2. Description of the Related Art
[0007] Diversionary devices, sometimes also referred to as stun
grenades or distraction devices, are generally intended for use by
law enforcement and military personnel to physiologically and
psychologically stun an intended victim or victims in high-risk
situations. Known diversionary devices generally comprise a housing
containing an energetic pyrotechnic charge and a firing arrangement
with a small time delay. When activated, the known diversionary
devices emit a loud noise, a pressure wave and a flash of light to
stun the intended victim but without expelling matter that might
cause physical injury. More recently, diversionary devices have
been developed which emit multiple bursts of noise, pressure and
light rather than a single burst. It is believed that this is more
disorientating; especially if the bursts become louder and more
intense giving the impression the device is getting closer to the
victim.
[0008] It is known to use a pyrotechnic charge housed in a
replaceable cartridge in a diversionary device. The known
cartridges are similar to the so called "flash-bang" cartridges
that are commercially available and used typically for scaring
birds and often comprise a cylindrical housing containing a
combustible fuze and a pyrotechnic charge. The length and
composition of the fuze determines the time delay between ignition
of the fuze and deflagration of the pyrotechnic charge. Such
cartridges are sometime referred to as "sound units."
[0009] In WO 2011086388 A1 the present inventor disclosed a
multi-burst diversionary device housing a number of replaceable
pyrotechnic cartridges. The device has a firing arrangement
incorporating a percussive ignition cap containing a primer charge.
When the cap is fired, a proportion of the heat and pressure given
off is directed onto the fuze of each of the cartridges so that the
fuzes of all the cartridges are ignited at the same time. To
provide a multi-burst effect, the cartridges have fuzes with a
different time delay arranged so that the pyrotechnic charges are
deflagrated sequentially. Whilst this arrangement is highly
effective, there are drawbacks. Generally speaking, in order to
obtain a longer delay it is necessary to increase the physical
length of the fuze resulting in a corresponding decrease in the
volume of pyrotechnic charge that can be included in a cartridge of
any given size. As a result, there is a limit on the number
cartridges that can be incorporated in a device before the length
of fuze required to provide a suitable delay for the later bursts
means that there is insufficient room for an effective amount of
the pyrotechnic charge. A further drawback is that each of the
cartridges in the device must have a different delay to produce
sequential firing. This requires that a range of cartridges with
different fuze delays be provided and that each device must be
loaded with a correct set of cartridges.
[0010] It is an object of the present invention to provide a
multi-burst diversionary device which overcomes or at least
mitigates the drawbacks of the known diversionary devices.
[0011] It is a further object of the invention to provide a
multi-burst diversionary device which is simpler in design and so
cheaper and easier to manufacture than known multi-burst
diversionary devices.
[0012] It is also an object of the invention to provide an
alternative method of igniting the fuzes of a plurality of
cartridges in a multi-burst diversionary device.
BRIEF SUMMARY OF THE PRESENT INVENTION
[0013] In accordance with a first aspect of the invention, there is
provided a diversionary device comprising a housing holding a
plurality of pyrotechnic cartridges arranged in series, each
cartridge having a combustible fuze and a pyrotechnic charge; and a
firing arrangement including a primer charge; the housing defining
a first flow path configured to channel hot gases from the primer
charge onto the fuze of a first cartridge in the series only, the
housing defining further flow paths configured to channel a portion
of the hot gasses given off on deflagration of the pyrotechnic
charge in each of the cartridges onto the fuze of an adjacent
downstream cartridge.
[0014] In a device in accordance with the first aspect of the
invention, only the fuze of a cartridge in the first compartment in
the series is ignited by the printer charge, the fuzes in
subsequent cartridges are ignited sequentially utilizing a portion
of the hot gases produced when the pyrotechnic charge of a
cartridge in the preceding compartment deflagrates. Sequentially
igniting successive cartridges in series gives rise to a
multi-burst effect without the need for the cartridges to have
fuzes with different time delays and so enables a multi-burst
device to be constructed to hold any desired number cartridges.
Indeed, all the cartridges may have a fuze with the same time delay
and the device could be loaded with a plurality of identical
cartridges. This significantly simplifies the manufacture and
supply of cartridges and the loading of the device. That said, it
will be appreciated that the cartridges need not all be the same.
For example, it may be desirable to use cartridges with different
pyrotechnic compositions to create a particular effect over the
series of bursts.
[0015] The further flow paths might be configured to channel a
portion of the hot gasses given off on deflagration of the
pyrotechnic charge in at least one of the cartridges onto the fuze
of at least two adjacent downstream cartridges.
[0016] The device may hold more than one series of cartridges, the
housing defining a first flow path configured to channel hot gases
from the primer charge onto the fuze of the first cartridge in each
series, the housing defining further flow paths configured to
channel a portion of the hot gasses given off on deflagration of
the pyrotechnic charge in each of the cartridges in each series
onto the fuze of an adjacent downstream cartridge in the
series.
[0017] Each cartridge may be held in a compartment defined in the
housing.
[0018] Each compartment may have a fuze end and a charge end, the
further flow paths being configured to fluidly connect a fuze end
of each compartment with the charge end of the preceding upstream
compartment in the series.
[0019] Each compartment may comprise a chamber defined within the
housing, the further flow paths connecting the chambers
sequentially in series, a fuze end region of each chamber in the
series downstream from the first chamber being connected by means
of a flow path with a charge end region of the preceding upstream
chamber in the series. The chambers may each have a substantially
cylindrical region in which at least part of a respective cartridge
is a close sliding fit.
[0020] The housing may also define flow paths for connecting each
chamber with atmosphere. For each pair of adjacent chambers in the
series, the housing may define a flow path which interconnects the
charge end region of the upstream chamber in the pair to the fuze
end region of the downstream chamber in the pair and which also
connects both end regions to atmosphere.
[0021] The primer charge may be provided in percussion cap, the
first flow path connecting the percussion cap with the fuze end of
the first compartment in the series. The device may further
comprise a firing mechanism for selectively activating the
percussion cap. The firing mechanism may comprise a firing pin
which is resiliency biased to a firing position in which it
contacts the cap to activate the primer charge, the pin being
movable from the firing position to a non-firing position in which
it is spaced from the primer charge against the bias force. The
firing mechanism may also comprise a release lever, the lever being
movable between a non-release position in which it holds the firing
pin in the non-firing position and a released position in which the
firing pin is able to move to the firing position under the bias
force. The firing mechanism may also comprise a removable safety
pin for holding the lever in the non-release position. The firing
pin may be provided on a striker plate.
[0022] At least some of the compartments in the series may be
arranged in an array, longitudinally overlapping one another. The
compartments could be disposed about a central axis generally
parallel to one another. The housing may comprise a main body
portion having a central axis with at least some of the
compartments disposed in the main body portion about the axis. The
main body portion may be generally cylindrical. The compartments
may be arranged so that the charge end of each compartment is
located adjacent the fuze end of the next downstream chamber in the
series. The housing may comprise a first end cap and a second end
cap, the end caps being releasably mountable to opposite ends of
the main body portion, the end caps defining the further flow paths
interconnecting compartments sequentially in series. The first end
cap may also comprise a mounting for receiving a firing mechanism
and define at least part of the first flow path for fluidly
connecting the primer charge with a fuze end of a first one of the
compartments in the series. The compartments may be arranged in two
or more rows about a central axis.
[0023] The compartments in the series may be arranged axially
in-line. In this case, the housing may be elongate having an
upstream end and a downstream end, the firing arrangement being
located at the upstream end. The housing may comprise a plurality
of housing sections releasably mountable to one another. The
housing may comprise at least two tabular housing members including
a first tubular housing member having an end cap at an upstream end
incorporating, or to which is mounted, the firing mechanism and a
final tubular housing member having a second end cap at a
downstream end; each pair of adjacent tubular housing members being
releasably interconnected by an adaptor. The first end closure and
each of the adaptors may define at a downstream end a recess which
opens into the interior of the adjacent downstream tubular housing
member, the recess being dimensioned to receive and hold a fuze end
of respective one of the pyrotechnic cartridges. Each of the
adaptors may also define a further recess at an upstream end which
opens into the interior of the adjacent upstream tubular housing
member for receiving a charge end of a respective one of the
pyrotechnical cartridges, the adaptor also defining a flow path
fluidly connecting the recess at the downstream end with the
further recess at the upstream end. The adaptor flow path may
comprise at least one flow passage which is offset from the axial
centreline of the recess. The tubular housing members may each have
one or more vent openings therethrough. In accordance with a second
aspect of the invention, there is provided a multi-burst
diversionary device comprising: a housing holding a plurality of
pyrotechnic cartridges and a firing arrangement operatively
connected with a first one of the cartridges to ignite said first
one of the cartridges only, the device comprising formations for
directing on to each of the remaining cartridges a portion of the
hot gas given off on deflagration another of the cartridges.
[0024] In accordance with a third aspect of the invention, there is
provided a method of operating a multi-burst diversionary device
comprising a plurality of pyrotechnic cartridges each cartridge
having a combustible fuze and a pyrotechnic charge, the method
comprising: a. using a primer charge to ignite the fuze of a first
one of the cartridges; b. sequentially igniting the fuzes of the
remaining pyrotechnic cartridges in series by directing a portion
of the hot gasses given off by an upstream cartridge in the series
when it deflagrates onto the fuze of the next adjacent downstream
cartridge.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0025] FIG. 1 is a perspective view of a first part of the main
body of a diversionary device in accordance with a first embodiment
of the invention;
[0026] FIG. 2 is similar to FIG. 1 but includes arrows indicating
the direction flow of fluid along the various fluid
passageways;
[0027] FIG. 3 is a longitudinal cross sectional view on an enlarged
scale through a typical pyrotechnic cartridge for use in a
diversionary device in accordance with the invention;
[0028] FIG. 4 is a side view of a main body member forming part of
a housing of a diversionary device in accordance with a second
embodiment of the invention;
[0029] FIG. 5 is an end view of the main body member of FIG. 4;
[0030] FIG. 6 is a cross sectional view taken on line A-A of FIG. 7
of a first end cap forming part of the housing of the diversionary
device in accordance with the second embodiment of the invention
for use with the main body member of FIGS. 4 and 5;
[0031] FIG. 7 is an end view of the first end cap of FIG. 6;
[0032] FIG. 8 is a side view showing hidden detail of second end
cap forming part of the housing of the diversionary device in
accordance with the second embodiment of the invention for use with
the main body member of FIGS. 4 and 5 and the first end cap of
FIGS. 6 and 7;
[0033] FIG. 9 is an end view of the second end cap of FIG. 8;
[0034] FIG. 10 is a schematic side view of the diversionary device
in accordance with the second embodiment;
[0035] FIG. 11 is a longitudinal cross-sectional view through a
diversionary device in accordance with a third embodiment of the
invention;
[0036] FIG. 12 is a side view of an adaptor forming part of the
device of FIG. 11;
[0037] FIG. 13 is an end view of the adaptor of FIG. 12;
[0038] FIG. 14 is a side view of a diversionary similar to that
shown in FIG. 11 but expanded to include three pyrotechnic
cartridges, with certain parts shown ghosted to enable internal
details to be seen;
[0039] FIG. 15 is schematic representation of an alternative
configuration of pyrotechnic cartridges which could be adopted in
diversionary device similar to that of the first embodiment of the
invention as illustrated in FIGS. 1 and 2; and,
[0040] FIG. 16 is a view similar to that of FIG. 10 illustrating an
alternative arrangement of pyrotechnic cartridges in a diversionary
device similar to that of the second embodiment of the invention as
illustrated in FIGS. 4 to 10.
REFERENCE NUMERALS USED IN THE DRAWINGS
[0041] 10 diversionary device [0042] 12 body member [0043] 12b end
cap [0044] 12c end cap [0045] 14 firing mechanism [0046] 16 mating
face [0047] 18 recess [0048] 20 chamber [0049] 22 pyrotechnic
cartridge [0050] 24 housing [0051] 26 end closure [0052] 28
pyrotechnic charge [0053] 30 fuze [0054] 32 extended region [0055]
40 fluid passageway [0056] 42 fluid passageway [0057] 44 fluid
passageway [0058] 46 further flow passageway [0059] 48 Y shaped
passageway [0060] 50 outlet [0061] 52 arrow [0062] 54 arrow [0063]
56 passageway [0064] 60 arrow [0065] 68 arrow [0066] 70 through
bore [0067] 72 end face [0068] 74 end face [0069] 76 spigot [0070]
78 end face [0071] 80 external thread [0072] 82 central bore [0073]
82a internal thread [0074] 83 percussion cap [0075] 84 end face
[0076] 85 firing mechanism [0077] 85a release lever [0078] 85b
safety pin [0079] 86 end face [0080] 88 central bore [0081] 88a
recessed region [0082] 90 bore [0083] 92 recess [0084] 94 bore
[0085] 96 recess [0086] 98 recess [0087] 100 vent hole [0088] 102
vent hole [0089] 104 recess [0090] 106 recess [0091] 108 recess
[0092] 110 vent hole [0093] 112 row [0094] 114 row [0095] 115
divider [0096] 116 flow path [0097] 118 flow path [0098] 120 vent
hole [0099] 122 main body section [0100] 124 threaded spigot [0101]
126 threaded spigot [0102] 128 recess [0103] 132 main body portion
[0104] 134 threaded spigot [0105] 136 recess [0106] 138 recess
[0107] 140 bore [0108] 142 main body section [0109] 144 threaded
spigot [0110] 145 recess
DETAILED DESCRIPTION OF THE INVENTION
[0111] Several embodiments of a diversionary device in accordance
with the present invention will now be described, by way of
non-limiting example only, with reference to the accompanying
drawings.
[0112] With reference to FIGS. 1 to 3, a diversionary device in
accordance with a first embodiment of the present invention is
indicated generally at 10. The device 10 has a housing with a main
body to which is mounted a firing mechanism, indicated
schematically at 14. The main body is formed in two parts, only one
of which 12 is illustrated, the other part being substantially a
mirror image of the part 12 shown. The part 12 is a generally
rectangular block of material having a mating face 16. The part 12
can be made of any suitable material such as a metallic material
including steel or aluminum/aluminum alloy. Formed within the
material are recesses 18 which one open on to the mating face 16.
The second part has a corresponding mating face and corresponding
recesses. The two parts 12 are connected together mating face to
mating face to form the main body and held together by a number of
releasable fastenings, such as screws (not shown). When connected
together, the opposed recesses 18 in the mating faces 16 of the two
parts define a number of cylindrical chambers 20a-20h arranged in a
common plane, and a number of fluid passageways which interconnect
the chambers fluidly in series and connect each of the chambers
with atmosphere at the exterior of the main body 12. The recesses
also define a first fluid passageway which fluidly connects only a
first of the chambers with the firing arrangement.
[0113] In the present embodiment, there are eight chambers in the
main body but the number of chambers can be varied as desired. Each
of the chambers 20 has a cylindrical region configured to receive a
cylindrical pyrotechnic cartridge 22, an example of which is shown
in FIG. 3 on an enlarged scale.
[0114] Each cartridge 22 has a cylindrical housing 24 closed at one
end by an end closure 26. The housing contains a pyrotechnic charge
28 located towards the closed end of the housing and an ignitable
and combustible fuze 30 at the open end. Each chamber 20 has a fuze
end 20' and a charge end 20'', the cartridges 22 being inserted in
the chambers with the open fuze at the fuze end 20' of each chamber
as illustrated schematically in chambers 20a to 20c in FIG. 1 with
the cross hatching representing the fuze 30. At the charge end, the
chambers have an extended region 32 of reduced diameter in
comparison with the cylindrical region into which the end closure
26 of the cartridge is blown when the pyrotechnic charge is ignited
and deflagrates.
[0115] The cartridges 22 may be similar to so called "flash-bang"
cartridges that are commercially available and used typically for
scaring birds. The cylindrical housing 24 may be made of paper or
cardboard or the like but any suitable material can be used. The
pyrotechnic charge 28 may be any suitable composition which
produces the required combination of sound, light and pressure. A
differently composed pyrotechnic charge 28 may be used in some/all
of the cartridges 22 in the device 10 to create different effects.
For example, the cartridges 26 may have different pyrotechnic
charge compositions so that when ignited sequentially, each
successive cartridge produces a louder noise, more light and more
pressure. This gives the impression that the device 10 is moving
closer to the victim even though the device is substantially
stationary.
[0116] Whilst it is expected that the device in accordance with the
invention will use pyrotechnic cartridges with a combustible fuze
30 to provide a delay between each successive deflagration
("flash-bang"), at least some pyrotechnic cartridges with no fuze
could be used, though this would result in a series of closely
spaced bangs.
[0117] Seven of the chambers 20b-20h are arranged parallel to one
another in a closely spaced array whilst the first chamber 20a is
inclined at an angle to the others and is more widely spaced at its
fuze end 20'. This positions the fuze end 20' of the first chamber
20a so as to be more easily connected with the firing arrangement
14 by a first fluid passageway 40. The firing arrangement is
releasably mountable to the main body 12 and houses a percussive
ignition cap containing a primer charge which emits a flash of heat
and pressure (hot gasses) when the cap is struck with a sufficient
force. The firing arrangement also includes a firing mechanism to
fire the ignition cap. This can be any suitable arrangement such as
a conventional spring loaded striker plate and release leaver
assembly of the type described in WO 2011086388 A1. However, any
suitable firing mechanism could be used such as an inertia
activated toggle of the type disclosed in EP 1705454 B. For
convenience, the term "flash" will be used in this description to
refer collectively to the heat, pressure wave, light, sound and
material given off by the primer charge in the percussion cap when
it is set off and/or by a pyrotechnic charge in one of the
cartridges 22 when it deflagrates. It will be understood, however,
that it is the hot gas or gases given off or produced by the
pyrotechnic charges which is of primary importance for use in
igniting a fuze 30 of a subsequent cartridge 22.
[0118] The firing arrangement includes a fluid passageway which
connects with the first fluid passageway 40 in the main body to
form a flow path along which at least a portion of the hot gasses
given off by the primer charge is able to flow into the fuze end
20' of the first chamber 20a. Fluid passageways 42, 44 defined in
the main body connect the fuze end and the charge end respectively
of the first chamber 20a to atmosphere at the exterior of the main
body. A further flow passageway 46 fluidly connects the charge end
of the first chamber 20a to the fuze end of the second chamber 20b.
The chambers are all positioned top to toe so that the fuze end of
one chamber is located next to the charge end of the adjacent
chamber or chambers. Adjacent pairs of the second to eighth
chambers 20b to 2h are each interconnected by a generally "Y"
shaped fluid passageway 48. The "Y" shaped passageway 48
interconnecting the second chamber 20b and the third chamber 20c
will be described in detail. This "Y" shaped passageway 48 includes
a first fluid passageway portion 48a extending coaxially from the
fuze end of the downstream chamber 20c to an outlet 50 at the edge
of the main body 12 where it opens into the atmosphere. A second
passageway portion 48b extends from the extended region 32 at the
charge end of the upstream chamber 20b to the first passageway
portion 48a approximately midway between the outlet 50 and the
chamber 20c. The second passageway portion 48b extends from a
position approximately midway along the extended region 32 so that
it is not blocked by the cartridge end closure 26 which is blown
into the end of the extend region when the cartridge is fired. The
second passageway is angled relative to the axis of the upstream
chamber 20b so that fluid flowing thought it is directed into the
first passageway portion 48a primarily in an outward direction
towards the outlet end 50 such that when the pyrotechnic charge in
chamber 20b deflagrates, most of the flash given off will pass out
of the main body through first passageway portion outlet 50 as
indicated by arrow 52 in FIG. 2. However, some of the flash,
including hot gases, will flow along the first passageway portion
48a into the fuze end of the downstream chamber 20c, as indicated
by arrow 54. The remaining pairs of chambers 20c and 20d, 2d and
20e, 20e and 20f, 20f and 20g, 20g and 20h are each interconnected
by a similar "Y" shaped passage way 48 and the charge end of the
final chamber 20h is connected to atmosphere by a passageway 56
which extends from the extended region 32 to an outlet 58 at the
edge of the main body.
[0119] In use, the device 10 is loaded with a cartridge 22 in each
of the chambers 20, the main body is assembled and the firing
arrangement with the primer charge mounted to the main body. When
the firing arrangement is activated, the primer charge gives off a
flash of pressure and heat and material including hot gasses which
passes through the first fluid flow passageway 40 into the fuze end
of the first chamber 20a, as indicated by arrow 60 and ignites the
fuze 30 of the cartridge in the first chamber 20a. After a short
delay determined by the fuze 30 of the first cartridge, the main
pyrotechnic charge 28b is ignited and deflagrates giving off a
larger flash of light, heat, pressure wave and sound. The majority
of the flash passes through the fluid passageways 42, 44 to
atmosphere as indicated by arrows 62 and 64 to produce a burst of
sound, light and pressure. However, as indicated by arrow 66, a
portion of the flash, including hot gas, passes along the fluid
flow passageway 46 to enter the fuze end of the second chamber 20b
where it ignites the fuze 30 of the cartridge in the second
chamber. After a further short delay, determined by the fuze 30 in
the second cartridge, the main pyrotechnic charge 28 in the second
cartridge deflagrates. The bulk of the flash given off by the
second cartridge passes out of the device through the first and
second fluid passage way portions 48a, 48b and outlet 50 of the "Y"
shaped passageway 48 interconnecting the second and third chambers
20b, 20c as indicated by arrows 52, though some will pass out of
the main body through the fluid passageway 46, the extended region
32 of first chamber 20a and fluid flow passageway 44. A proportion
of the flash of heat and pressure including hot gasses given off by
the pyrotechnic charge of the cartridge in the second chamber 10b
though passes along the first passage portion 48a into the fuze end
of the third chamber 20c, as indicated by arrow 54, where it
ignites the fuze 30 of the cartridge in the third chamber. The
process continues in a chain-like reaction, with all the remaining
cartridges 22 in the device being sequentially ignited from the
flash given off by the previous, upstream cartridge in the series.
Connecting the cartridges together sequentially in series in the
manner of a daisy chain enables the cartridges to he fired
sequentially without the need to use different length fuzes. This
means that virtually any number of cartridges could be included in
the device without unduly limiting the amount of pyrotechnic charge
that can be incorporated in those cartridges that are fired later
in the sequence and allows the device to be loaded with a plurality
of identical cartridges if desired.
[0120] FIG. 15 illustrates schematically an alternative
configuration of cartridges 22 in a planar array that could be
adopted in a device 10 as described above. In this configuration,
the cartridges are arranged in two rows and the arrows 68 indicate
the flow of hot gases from one cartridge to next in the series in
order that, with the exception of the first cartridge which is
ignited from a primer charge, each of the remaining cartridges are
ignited in turn by the hot gasses given off when the previous
cartridge ignites. It will be appreciated than many other
configurations could be adopted by suitable design of the cartridge
chambers and interconnecting flow paths.
[0121] It will be appreciated that the concept of sequentially
igniting subsequent cartridges in a multi-burst diversionary device
is not limited to devices where the chambers are arranged in a
common plane but can be adapted for use in devices with a range of
different designs, provided that fluid flow paths for directing or
channeling a proportion of the flash, and in particular the hot
gas, given off or generated by each cartridge as it deflagrates
onto the fuze an adjacent cartridge downstream in the series are
defined. For example, the chambers could be aligned co-axially
in-line with one another or they could be arranged about a common
axis in a cylindrical housing as described in the following
embodiments.
[0122] FIGS. 4 to 10 illustrate a further embodiment of a
diversionary device 10' in accordance with the invention in which
the housing is generally cylindrical and the compartments 20 are
arranged in a circular array about a central longitudinal axis.
[0123] The housing 12 of the device 10' comprises three main parts,
a main cylindrical body member 12a, a first end cap 12b and a
second end cap 12c. Extending through the main body 12a is a small
diameter central through bore 70 aligned with a central
longitudinal axis of the main body. Disposed in and about the
central through bore and longitudinal axis is an array of 6 larger
diameter through bores 20a to 20f which define compartments or
chambers for receiving pyrotechnic cartridges 22, such as those
shown in FIG. 3. The compartments 20 are not equi-spaced about the
central axis but arranged into adjacent pairs.
[0124] The end caps 12b and 12c are releasably mounted to opposite
ends of the main body to hold the cartridges 22 in their respective
compartments and serve to define flow paths that connect the
compartments in series for sequential, serial ignition of the
cartridges.
[0125] A first end cap 12a comprises a cylindrical disc portion
having an outer diameter which is substantially the same as that of
the main body 12a and which has a planar end face 72 which abuts an
end face 74 of the main body when the housing is assembled. A
spigot 76 projects axially out from the other end face 78 of the
disc. The spigot 76 has an external thread 80 on to which can be
mounted a firing pin arrangement. A central bore 82 extends through
the first end cap. An inner end region 82a of the bore has an
internal thread whilst an outer end region is 82b is recessed to
hold a percussive ignition cap 83 containing a primer charge.
[0126] The second end cap 12c is also in the form a cylindrical
disc having an outer diameter which is substantially the same as
that of the main body 12a and which has a planar end face 84 which
abuts the other end face 86 of the main body when the housing is
assembled. A central bore 88 extends through the centre of the
disc, the bore having a wider diameter recessed region 88a at its
outer end. When the housing 12 is assembled, the end caps 12b, 12c
are clamped firmly to the ends of the main body 12a by means of an
elongate screw (not shown) which is inserted though the central
bore 88 in the second end cap and the central bore 70 in the main
body to engage with the internal thread 82a in the central bore of
the first end cap. The elongate screw having a head which is
received in the recess 88a of the central bore 88 in the second end
cap.
[0127] The cartridges 22 in the compartments 20a-20f are arranged
head to toe, with the fuzes 30 of the cartridges in the first,
third, and fifth compartment 20a, 20c, 20e being located adjacent
the first end cap 12b and the fuzes 30 of the cartridges in the
second, fourth and sixth compartments 20b, 20d, 20f being located
adjacent the second end cap.
[0128] A bore 90 extends through the disc portion of the first end
cap 12b in registration with the fuze end of the first compartment
20a. A radially extending recess 92 is provided in the inner face
of the disc which merges with the bore 90 and extends radially
inwardly. An angled bore 94 connects the interior of the recess
with an outer end region of the central through bore 82. The
central through bore 82, the angled bore 94 and the recess 92
together define a first flow path along which the hot gasses given
off by the primer charge in the ignition cap 83 in the outer
recessed end of the bore 82 can flow to enter the fuze end of the
first compartment 20a. The bore 90 forms an exhaust vent through
which a portion of the flash given off when the pyrotechnic charge
of the cartridge in the first compartment deflagrates can escape to
atmosphere.
[0129] Two arcuate recesses 96, 98 are formed in the inner face 72
of the first end cap 12a, each recess being connected to atmosphere
by an exhaust vent hole 100 extending through the remainder of the
end cap to the outer end face 78 of the disc portion. A first of
the recesses 96 partially overlaps the ends of the second and third
compartments 20b, 20c in the main body to define a flow path
fluidly interconnecting the charge end of the second compartment
20b with the fuze end of the third compartment 20c. The recess 96
and the vent hole 100 also fluidly connect the two chambers with
atmosphere. The second of the recesses 98 partially overlaps the
ends of the fourth and fifth compartments 20d, 20e in the main body
to define a flow path fluidly interconnecting the charge end of the
fourth compartment 20d with the fuze end of the fifth compartment
20d. The recess 98 and the vent hole 100 also connect the two
chambers 20d, 20e with atmosphere. A further exhaust vent hole 102
is formed through the disc portion of the first end cap in line
with the sixth compartment 20f to connect the compartment with
atmosphere.
[0130] Three circular recesses 104, 106, 108 are formed in the
inner mating surface 84 of the second end cap 12c equi-spaced about
its centre. A smaller diameter exhaust vent hole 110 is formed
through the remainder of the disc portion at the base of each of
the recesses to connect each recess with atmosphere. The recesses
104, 106, 108 are positioned so that each one aligns with a
respective pair of the compartments 20a-20f. The circular recesses
104, 106, 108 are dimensioned so that they only partially overlap
the ends of the adjacent compartments so as to fluidly connect them
whilst the second end cap 12c holds the cartridges in the
compartments. The exhaust vent holes 1 10 fluidly connected the two
respective compartments to atmosphere. In this embodiment, a first
circular recess 104 aligns with the ends of the first and second
compartments 20a, 20b in the main body so as to fluidly connect the
charge end of the first compartment 20a with the fuze end of the
second compartment 20b, the vent hole 110 fluidly connecting the
compartments 20a, 20b with atmosphere. A second circular of the
recesses 106 aligns with the ends of the third and fourth
compartments 20c, 20d in the main body so as to fluidly connect the
charge end of the third compartment 20c with the fuze end of the
fourth compartment 20 d, the vent hole 110 fluidly connecting the
compartments 20c, 20d with atmosphere. A third of the circular
recesses 108 aligns with the ends of the fifth and sixth
compartments 20e, 20f in the main body so as to fluidly connect the
charge end of the fifth compartment 20e with the fuze end of the
sixth compartment 20f, the vent hole 110 fluidly connecting both
compartments 20e, 20f with atmosphere.
[0131] In the assembled device 10', the recesses and vent holes in
the end caps 12b, 12c form flow paths which connect all the
compartments 20a-20f sequentially in series. In other words, they
form a chain of flow paths which allow each cartridge downstream
from the first to be ignited by the hot gasses from the preceding
cartridge in the series when it deflagrates.
[0132] The fuze end of the first chamber 20a is fluidly connected
with the primer charge in the firing arrangement via the recess 92,
the angled bore 94 and the axial bore 82 in the first end cap which
collectively form a first fluid passageway. The charge end of the
first compartment 20a is connected with the fuze end of the second
compartment 20b by the first circular recess 104 in the second end
cap. The charge end of the second compartment 20b is connected with
the fuze end of the third compartment 20c by the first arcuate
recess 96 in the first end cap. The charge end of the third
compartment 20c is connected with the fuze end of the fourth
compartment 20d by the second circular recess 106 in the second end
cap. The charge end of the fourth compartment 20d is connected with
the fuze end of the fifth compartment 20e by the second arcuate
recess 98 in the first end cap. Finally, the charge end of the
filth compartment 20e is connected with the fuze end of the sixth
compartment 20f by the third circular recess 108 in the second end
cap.
[0133] In use, a pyrotechnic cartridge 22 is loaded into each of
the compartments 20a-20f in the main body 12a in the appropriate
orientation. The end caps 12b, 12c are mounted to the ends of the
main body and secured in position. A percussion cap 83 including a
primer charge is loaded into the recessed end 82b of the axial bore
in the first end cap 12b and a firing mechanism 85 is mounted to
the first end cap 12b. The firing mechanism 85 is a conventional
firing mechanism of the type disclosed in WO 2011086388 A1 and
comprises a release lever 85a for controlling the release of a
spring loaded striker plate which when released is urged to strike
the percussion cap in order to set off the primer charge and a
removable safety pin 85b. However, other types of firing mechanism
can be adopted. When the device 10 is activated and the primer
charge set off, the flash of heat, pressure and material given off
by the primer charge passes through the first fluid passageway
comprising the axial bore 82, the angled bore 94, and the recess 92
in the first end cap and enters the fuze end of the first
compartment 20a to ignite the fuze 30 of the cartridge in the first
compartment. After a short delay, the pyrotechnic charge 28 in the
first cartridge is ignited and deflagrates giving off a large flash
of light, heat, pressure wave, and sound. The majority of this
flash passes out through the vent hole 90 and the vent hole 110 in
the first circular recess 104. However, a portion of the flash
including hot gas is guided by the first circular recess to enter
the fuze end of the second compartment 20b where it ignites the
fuze of the second cartridge in the second compartment 20b. When
the second cartridge deflagrates, the majority of the flash given
off passes out though the vent hole 110 in the first circular
recess 104 and the vent hole 100 in the first arcuate recess 96 in
the first end cap 12b. A portion of the hot gasses though is guided
by the first arcuate recess 96 to enter the fuze end of the third
compartment 20c to ignite the fuze of the third cartridge in the
third compartment. This process continues with each cartridge being
ignited by a portion of the hot gasses (flash) given off by the
cartridge in the previous upstream compartment by means of the flow
paths as described above. FIG. 10 is a somewhat schematic side view
of the assembled device 10' which is ghosted to show the positions
of the cartridges 22 in main body member 12a, though details of the
compartments 20a-20f themselves are omitted for clarity. Arrows 54
indicate the flow of hot gas from one cartridge when it deflagrates
onto the fuze of the next adjacent downstream cartridge to ignite
the fuze of the downstream cartridge. The arrows 52 indicate the
movement of flash to atmosphere through the exhaust vent holes when
each cartridge deflagrates.
[0134] It will be appreciated various changes can be made to the
device 10' without departing from the inventive concept. For
example the number of compartments in the main body 12a can be
changed with an appropriate change to design of the end caps 12b,
12c to ensure that the compartments are connected in series. Other
changes can also be made. For example, elongate actuate holes could
be provided through the disc part of the first end cap 12b rather
than the recesses 96, 98 and vent holes 100. Similarly, the
circular recesses 104, 106, 108 in the second end cap 12c could be
replaced by simple through holes. These changes would allow the
compartments to vent more easily ensuring that a sufficiently large
flash is emitted whilst the shroud effect of the end cap
surrounding the holes constrains sufficient heat and pressure (hot
gas) given off by one cartridge when it deflagrates to pass though
to the fuze end of the next compartment. The disc portion may need
to be of sufficient thickness to ensure that it channels sufficient
of the hot gasses onto the fuze of the downstream cartridge but
this can be established for each application relatively easily by
means of trial and error if necessary. With the benefit of the
teaching in this patent specification, those skilled in the art
will have no difficulty in configuring the housing so as to deflect
part of the hot gasses given off by each cartridge onto the fuze of
an adjacent downstream cartridge.
[0135] FIG. 16 illustrates a modified version of the device 10'a in
which the cartridges are arranged in two rows 112, 114 stacked one
above the other (as shown) in modified main body portion 12a' and
separated by a divider 115. The main body portion defines flow
paths 116, 118 which direct hot gases between pyrotechnic
cartridges 22 vertically adjacent one another in the two rows so
that all the cartridges can be ignited sequentially in series. The
flow paths are arranged so that a first cartridge 22a in the row
112 adjacent the first end cap 12b is ignited from the primer
charge. A proportion of the flash given off when the first
cartridge 22a deflagrates is directed by means of flow passage 116
on to the fuze of a second cartridge 22b immediately below the
first cartridge in the row 114 adjacent the second end cap 12b.
Flash from the second cartridge 22b is directed by a suitable flow
path defined in the second end cap 12c on to the fuze of a third
cartridge in the same row 114, whilst flow passage 118 directs a
proportion of the flash from the third cartridge 22c on to the fuze
of a fourth cartridge 22d in the first row 112 immediately above
the third cartridge. Similar arrangements interconnect all the
remaining pyrotechnic cartridges 22 in the device. It will be
appreciated that various different configurations of cartridges can
be adopted by suitable design of the chambers and interconnecting
flow paths.
[0136] FIGS. 11 to 14 illustrate a still further embodiment of a
diversionary device 10'' in accordance with the invention. In the
device 10'' according to this embodiment, the compartments and
cartridges are aligned axially in-line with one another. In the
embodiment as shown in FIG. 12, there are two compartments 20a, 20b
each housing a corresponding cartridge 22a, 22b. However, the
device is modular in nature and any number of additional
compartments/cartridges can be added and FIG. 14 illustrates the
device 10'' having three compartments 20a, 20b, 20c.
[0137] The device 10'' comprises a housing 12 including a first end
cap 12b at an upstream end of the device and a second end cap 12c
at a downstream end. At least two tubular housing members 12d, 12e,
12f are arranged between the first and second end caps with
adjacent tubular housing members being interconnected by an adaptor
12g. The components of the housing can be made of any suitable
materials such as metallic materials including steel or
aluminum/aluminum alloy.
[0138] The tubular housing members 12d, 12e, 12f are identical and
interchangeable. They each have an internal thread at either end
for connection with an end cap 12b, 12c or adaptor 12g and a number
of exhaust vent holes 120.
[0139] The first end cap 12b is located at the upstream end of the
device 10''. It includes a main body section 122 with a first
threaded spigot 124 which projects from the inner end of the main
body section for engagement with the thread at one end of a first
tubular housing member 12d to secure them together. A second
threaded spigot 126 projects from the outer end of the main body
section 122. The second spigot 126 is smaller in diameter than the
first and has an external thread on to which can be mounted a
firing mechanism 85 similar to that of the previous embodiment, as
is shown in FIG. 14. A circular recess 128 is formed coaxially in
the inner end of the first threaded spigot. The recess 128 is
dimensioned to receive and hold the fuze end of a pyrotechnic
cartridge 22a. The recess may have tapered side walls for ease of
inserting the cartridge. An axial bore 82 extends through the
second spigot 126 and opens into the recess 128. The bore has a
stepped larger diameter portion 82a at its outer end in which a
percussion cap 83 containing a primer charge can be mounted. The
firing mechanism 85 includes a striker plate and/or a firing pin
which is urged to strike the percussion cap 83 when the device 10''
is activated so as to produce a flash of heat and pressure (hot
gasses) and material which travels down the axial bore 82 to ignite
the fee of the first cartridge 22a. The axial bore 82 in this
embodiment comprises a first flow path whilst the downstream recess
128 in the first end cap 12b and the corresponding tubular housing
member 12d together define the first compartment 20a for receiving
the first pyrotechnic cartridge 22a.
[0140] Each adaptor 12g has a main body portion 132 with a threaded
spigot 134 projecting from either end. The spigots 134 are similar
to the first spigot 124 on the first end cap 12b and are configured
to engage with the threads at the ends of two adjacent tabular
housing members 12d & 12e or 12e & 12f to join them
together. A circular and tapered recess 136 is formed at the
downstream end of each adaptor for holding the fuze end of a
cartridge 22b, 22c in a manner similar to the recess 128 in the
first end cap 12b. A further circular recess 138 is formed in the
upstream end of each adaptor to hold the charge end of the upstream
cartridge 22a, 22b. The two recesses are fluidly connected by means
of four bores 140 equi-spaced about a longitudinal axis of the
device. The downstream recess 136 in the adaptor and the adjacent
downstream tubular housing member 12e, 12fd together define a
compartment 20b, 20c for receiving the respective pyrotechnic
cartridge 22b, 22c. The downstream end of the last tubular housing
member, 12e, 12f is closed by the second end cap 12c. The second
end cap 12c comprises a main body section 142 with a threaded
spigot 144 projecting from the upstream end of the main body
section for engagement with the thread at the end of the last
tubular housing member 12e, 12f. A circular recess 145 is formed in
the upstream end of the second end cap to hold the charge end of
the upstream cartridge 22b, 22c.
[0141] When the device is activated, a flash of heat and pressure
and material produced when the primer charge in the percussion cap
83 is set off travels down the axial bore 82 in the first end cap
12b and ignites the fuze of the first cartridge 22a. After a delay
determined by the fuze, the first cartridge deflagrates giving off
a larger flash of heat, pressure wave, sound and light. The bulk of
this flash passes out through the vent holes 120 in the first
tubular housing member but a portion of the hot gas in particular
passes through the recess 138 in the upstream end of the adaptor
and the four bores 140 to ignite the fuze of the second cartridge
22b. After a further delay, the pyrotechnic charge in the second
cartridge deflagrates giving of a flash of heat, pressure, sound
and light, most of which passes out through the vent holes 120 in
the second tubular housing member 12e. Where the device 10'' has
more than two cartridges, the process continues with each cartridge
in the chain being ignited by the deflagration of the charge in the
preceding upstream cartridge. In FIG. 14, the arrows 52
schematically illustrate the flow paths of the flash passing out
through the vent holes from each cartridge as it deflagrates and
the arrows 54 indicate the flow path for hot gasses from one
chamber to the next to cause sequential firing of the cartridges.
It will be appreciated that the carriages are set off sequentially
and not simultaneously.
[0142] It has been found that it is advantageous to offset the flow
path through the adaptor 12g from the central axis of the
cartridges hence the use of the offset bores 140. However, it will
be appreciated that the design of the flow path could be varied in
a number of ways and is not limited the arrangements shown.
[0143] The main body portions 122, 132, 142 of the end caps and the
adaptor have a hexagonal outer profile so that the device 10'' will
tend to come to a rest more quickly on a surface when thrown as
compared with a device which is wholly cylindrical. Nevertheless,
this feature is not essential to the main inventive concept.
[0144] If more "bangs" are required, the device 10'' can be
extended by using an additional adaptor 12g and tubular housing
member 12d, 12e, 2f for each additional cartridge. In each device
10'' the first end cap 12b is mounted at the upstream end of the
first tubular housing member and the second end cap 12c mounted to
the downstream end of the last tubular housing member, with each
adjacent pair of tubular housing members being interconnected by an
adaptor 12g.
[0145] The above embodiments are described by way of example only.
Many variations are possible without departing from the scope of
the invention as defined in the appended claims. For example,
generally it is expected that a diversionary device in accordance
with the invention, all the pyrotechnic cartridges will be
interconnected in a single series so as to be ignited sequentially.
However, the cartridges could be arranged in more than one series,
with a first cartridge in each series being ignited from a primer
charge and the remaining cartridges in each series being ignited by
the hot gas given off when the previous cartridge in the series
deflagrates. In a further alterative, the cartridges may be
arranged in a series which splits into two or more paths. For
example, two cartridges might both be ignited from the hot gas
given off by a single previous cartridge in a series. This
arrangement could be used to produce a loud bang at the end of a
series by setting off two cartridges at the same time.
* * * * *