U.S. patent application number 13/376085 was filed with the patent office on 2012-06-14 for incendiary capsule.
Invention is credited to Vincenzo Foti, Robert Andrew Stevenson.
Application Number | 20120145830 13/376085 |
Document ID | / |
Family ID | 43298222 |
Filed Date | 2012-06-14 |
United States Patent
Application |
20120145830 |
Kind Code |
A1 |
Stevenson; Robert Andrew ;
et al. |
June 14, 2012 |
INCENDIARY CAPSULE
Abstract
An incendiary capsule has a body forming a single compartment
containing a first part of a two part ignition system and a
quantity of a pyrotechnic heat source (PHS). The capsule is
initiated by injecting, when ready for use, a quantity of a second
part of the two part ignition system. The ignition system generates
sufficient heat to initiate the PHS, which burns at a substantially
higher temperature than the ignition system.
Inventors: |
Stevenson; Robert Andrew;
(Jandakot, AU) ; Foti; Vincenzo; (Cecil Park,
AU) |
Family ID: |
43298222 |
Appl. No.: |
13/376085 |
Filed: |
June 4, 2010 |
PCT Filed: |
June 4, 2010 |
PCT NO: |
PCT/AU10/00694 |
371 Date: |
February 22, 2012 |
Current U.S.
Class: |
244/137.1 ;
102/364 |
Current CPC
Class: |
F42B 12/44 20130101;
A62C 3/0285 20130101 |
Class at
Publication: |
244/137.1 ;
102/364 |
International
Class: |
B64D 1/04 20060101
B64D001/04; F42B 12/44 20060101 F42B012/44 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 4, 2009 |
AU |
2009902574 |
Claims
1-30. (canceled)
31. An incendiary capsule comprising: a capsule body; a quantity of
a pyrotechnic heat source (PHS) disposed in the capsule body; and,
a quantity of a first part of a two part ignition system disposed
in the capsule body, the first part being reactive with a second
part of the ignition system which when contacted by the first part
in the capsule body causes an exothermic reaction which generates
sufficient heat to ignite the PHS.
32. The incendiary capsule according to claim 31 wherein the PHS
comprises a liquid impervious coating or covering.
33. The incendiary capsule according to claim 32 wherein the liquid
impervious coating or covering comprises a liquid which dries or
sets on the thermite to form liquid impervious layer on the
PHS.
34. The incendiary capsule according to claim 32 wherein the liquid
impervious covering or coating comprises an adhesive tape
comprising a layer of adhesive for adhering onto the PHS, the layer
of adhesive provided on a liquid impervious backing strip.
35. The incendiary capsule according to claim 32 wherein the liquid
impervious coating or covering is a coating of a plastics film.
36. The incendiary capsule according to claim 32 wherein the liquid
impervious coating or covering is a container made of a material
that ignites at or below the temperature generated by the
exothermic reaction.
37. An incendiary capsule according to claim 32 wherein the PHS is
in the form of a pellet.
38. The incendiary capsule according to claim 37 wherein the PHS
comprises thermite.
39. The incendiary capsule according to claim 31 wherein the PHS is
a compound comprising, by weight: 40-50% barium nitrate 15-20%
potassium nitrate 10-15% sulphur 15-20% aluminium 1-5% gum
arabic
40. The incendiary capsule according to claim 32 wherein the liquid
impervious coating comprises a solvent or solvent mixture applied
as a liquid on the PHS and subsequently allowed to dry to form the
coating.
41. The incendiary capsule according to claim 40 wherein the
solvent mixture comprises a mixture of shellac and methylated
spirits.
42. The incendiary capsule according to claim 31 wherein the
capsule body consists of a single sealed compartment containing the
first part of the two part ignition system and the PHS.
43. The incendiary capsule according to claim 31 wherein the
capsule body has an opening through which the thermite and first
part of the ignition system are deposited into the capsule, and a
seal that extends across and seals the opening.
44. A belt of incendiary capsules comprising: a plurality of
capsules according to claim 31; and, respective couplings between
adjacent capsules, the couplings joining the capsule bodies in a
side by side arrangement to form a belt.
45. The belt according to claim 44 wherein the couplings are formed
integrally with the capsule bodies.
46. The belt according to claim 45 wherein the couplings are made
of the same material as the capsule bodies.
47. The incendiary capsules according to claim 32 wherein the first
part of the ignition system is potassium permanganate.
48. The incendiary capsules according to claim 47 wherein the
second part of the ignition system is glycol.
49. A method of producing a burning heat source on the ground
comprising: providing one or more capsules according to claim 31;
carrying the one or more capsules on an aircraft; holding a supply
of a second part of the two part ignition system on the aircraft;
flying the aircraft over the ground; while flying the aircraft
depositing a quantity of the second part of the ignition system
into one or more selected capsules; and, dropping the or each
selected capsules with the second part of the ignition system from
the aircraft.
50. The method according to claim 49 wherein the aircraft is flown
at a height and the first and second parts of the ignition system
are provided in respective quantities such that the dropped
capsules reach the group prior to ignition of the PHS.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an incendiary capsule
particularly, although not exclusively, for use in airborne fire
control and forestry management procedures such as back
burning.
BACKGROUND OF THE INVENTION
[0002] It is known to drop incendiaries from air craft such as
helicopters and light fixed wing aircraft for the purposes of
forestry management and back burning. One known incendiary is in
the form of a small sphere of approximately 32 mm diameter of a
plastics material filled with a quantity of potassium permanganate
granules or powder. The sphere is injection moulded from extruded
plastic. A small hole is formed in the sphere to allow it to be
filled with potassium permanganate. The hole is then sealed with
wax or glue. The spheres are placed in a hopper which feeds the
sphere sequentially to a chute where they are injected with a small
volume of glycol. The potassium permanganate and glycol react
exothermically generating a flame.
[0003] The inventor developed an alternate form of incendiary
described in U.S. Pat. No. 6,877,433 in which the incendiary
comprises a plurality of containers containing a volume of
potassium permanganate which is subsequently injected with a volume
of glycol. The containers are coupled together to form a belt which
is fed through a dispensing machine that sequentially injects the
capsules with glycol and separates capsules from the belt for
subsequent dispensing.
SUMMARY OF THE INVENTION
[0004] One aspect of the invention provides an incendiary capsule
comprising: [0005] a capsule body; [0006] a quantity of a
pyrotechnic heat source (PHS) disposed in the capsule body; and,
[0007] a quantity of a first part of a two part ignition system
disposed in the capsule body, the first part being reactive with a
second part of the ignition system which when contacted by the
first part in the capsule body causes an exothermic reaction which
generates sufficient heat to ignite the PHS.
[0008] The PHS may comprise a liquid impervious coating or
covering.
[0009] The liquid impervious coating or covering may comprise a
liquid which dries or sets on the PHS to form liquid impervious
layer on the PHS.
[0010] The liquid impervious covering or coating may comprise an
adhesive tape comprising a layer of adhesive for adhering onto the
PHS, the layer of adhesive provided on a liquid impervious backing
strip.
[0011] The liquid impervious coating or covering may comprise a
coating of a plastics film.
[0012] The liquid impervious coating or covering may comprise a
container made of a material that ignites at or below the
temperature generated by the exothermic reaction.
[0013] The PHS may be provided in the form of a pellet.
[0014] The capsule body may comprise has an opening through which
the PHS and first part of the ignition system are deposited into
the capsule, and a seal that extends across and seals the
opening.
[0015] The capsule body may be made of a plastics material and be
provided with a flat bottom wall and a frusto-conical side wall
wherein the side wall reduces in diameter from the opening to the
bottom wall.
[0016] The capsule body may be provided with a lip extending about
the opening and lying on a plane substantially parallel to a plane
containing the bottom wall.
[0017] The seal may comprise a layer of plastics material.
[0018] The seal may comprise a layer of transparent or translucent
plastics material.
[0019] The PHS may comprise thermite or may be based on a thermite
like composition.
[0020] In one embodiment the PHS comprises by weight: [0021] 40-50%
barium nitrate [0022] 15-20% potassium nitrate [0023] 10-15%
sulphur [0024] 15-20% aluminium [0025] 1-5% gum arabic
[0026] When the PHS is in the form of a pellet the liquid
impervious coating may be a water proof coating and may comprise a
solvent or a solvent mixture. For example in one embodiment the
water proof coating comprises a mixture of shellac and methylated
spirits. The PHS pellet can be dipped in a bath of such a mixture
and subsequently removed to allow drying of the mixture on the
pellet thereby forming the coating on the pellet. In this example
the mixture may comprise between ten to thirty parts methylated
spirits to one part shellac. In another example the mixture
comprises about twenty parts methylated spirits to one part
shellac.
[0027] A second aspect of the invention may provide a belt of
incendiary capsules comprising: [0028] a plurality of capsules
according to the first aspect; and, [0029] respective couplings
between adjacent capsules, the couplings joining the capsule bodies
in a side by side arrangement to form a belt.
[0030] The couplings may be formed integrally with the capsule
bodies.
[0031] The couplings may be made of the same material as the
capsule bodies.
[0032] The couplings may be formed with the same thickness as the
side walls of the capsule bodies.
[0033] The first part of the ignition system may comprise potassium
permanganate.
[0034] The second part of the ignition system may comprise
glycol.
[0035] A third aspect of the invention may provide an incendiary
system comprising: [0036] one or more incendiary capsules according
to the first aspect or a belt of incendiary capsules according to
the second aspect; and, [0037] a dispensing apparatus comprising a
volume of the second part of the ignition system and a mechanism
for injecting a quantity of the second part of the ignition system
into each incendiary capsule.
[0038] The apparatus may inject the volume of the second part of
the ignition system through the seal of each incendiary
capsule.
[0039] The invention also provides a method of producing a burning
heat source on the ground comprising: [0040] providing one or more
capsules according to the first aspect; [0041] carrying the one or
more capsules on an aircraft; [0042] holding a supply of a second
part of the two part ignition system on the aircraft; [0043] flying
the aircraft over the ground; [0044] while flying the aircraft
depositing a quantity of the second part of the ignition system
into one or more selected capsules; and, [0045] dropping the or
each selected capsules with the second part of the ignition system
from the aircraft.
[0046] In one embodiment the aircraft is flown at height and the
first and second parts of the ignition system are provided in
respective quantities wherein the or each dropped capsule reaches
the group prior to ignition of the PHS.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] Embodiments of the present invention will now be described
by way of example only with reference to the accompanying drawings
in which:
[0048] FIG. 1A is a top view of a belt of the incendiary capsules
in accordance with an embodiment of the present invention;
[0049] FIG. 1B is a section view of an incendiary capsule shown in
FIG. 1A;
[0050] FIG. 2 is a top view of the incendiary capsule belt shown in
FIG. 1A showing empty incendiary capsules, except for the right
most capsule in which is disposed a quantity of PHS in the form of
a pellet;
[0051] FIG. 3 is a side view of the incendiary capsule belt shown
in FIG. 1A;
[0052] FIG. 4 is a bottom view of the incendiary capsule belt shown
in FIG. 1A;
[0053] FIG. 5 is a plan view of the PHS pellet shown in FIG. 2;
[0054] FIG. 6 is a side view of the PHS pellet shown in FIG. 5.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0055] FIGS. 1A and 1B illustrate an embodiment of an incendiary
capsule 10 in accordance with the present invention. FIG. 1A
illustrates a plurality of incendiary capsules 10 joined together
in the side by side arrangement to form a flexible incendiary
capsule belt 12. FIG. 1B depicts a section view through an
incendiary capsule 10. Each incendiary capsule 10 comprises a
capsule body 14 which contains a quantity of PHS 16 and a first
part 18 of a two part ignition system. The second part of the
ignition system (not shown) is injected into a capsule 10 when the
capsule 10 is ready for use, and reacts with the first part 18 to
cause an exothermic reaction which generates sufficient heat to
ignite the PHS 16.
[0056] In the present embodiment, the first part 18 of the ignition
system comprises potassium permanganate granules. PHS 16 is
provided in the form of a pellet although it is not essential that
the PHS be provided in this form. For example the PHS may also be
provided in the form of granules or powder.
[0057] The PHS may comprise thermite or a thermite like compound or
is otherwise based on thermite or a thermite like compound.
[0058] In general terms, thermite comprises a composition of a
metal powder and metal oxide which deflagrates at extremely high
temperatures typically in the order of 2,500-3,500.degree. C. The
metal powder in the thermite may comprise one or more of aluminium,
magnesium, calcium, titanium, zinc, silicon, or boron. The metal
oxide may comprise one or more of boron (III) oxide, silicon (IV)
oxide, chromium (III) oxide, magnesium (IV) oxide, iron (III)
oxide, iron (II, III) oxide, copper (II) oxide, and lead (II, IV)
oxide.
[0059] In one example the PHS comprises a compound, by weight of:
[0060] 40-50% barium nitrate [0061] 15-20% potassium nitrate [0062]
10-15% sulphur [0063] 15-20% aluminium [0064] 1-5% gum arabic
[0065] The PHS is pressed to form pellets, with the gum arabic
acting as a binder.
[0066] FIG. 2 illustrates the belt 12 of empty incendiary capsules
10 save for the right most capsule 10 in which is disposed a PHS
pellet 16. The PHS pellet 16 occupies a relatively small volume of
the capsule body 14 which is, for example less than 25% of the
volume. FIGS. 5 and 6 depict a PHS pellet 16. The pellet has a
diameter of approximately 11 mm and a thickness which reduces from
a maximum of about 4 mm along a central axis to about 2 mm at its
edge.
[0067] The PHS 16 is covered or coated with a liquid impervious and
more specifically water proof material. The type of liquid
impervious material used and its form may vary. When the PHS 16 is
in the form of a pellet, the liquid impervious material may be
provided initially as a liquid which is sprayed on the pellet or
into which the PHS pellet is dipped, where the liquid subsequently
dries or sets to create a liquid impervious layer or coating on the
PHS pellet 16. In an alternate form, the liquid impervious material
may be applied as adhesive tape which sandwiches the pellet 16. The
adhesive tape comprising a layer of adhesive material, that
contacts the pellet 16, provided on a liquid impervious backing
strip. Indeed, when the PHS is in the form of a powder or granules,
the powder or granules may be wrapped in an adhesive tape. In an
alternate form, the covering or coating may be in the form of a
thin film of plastics material such as cling wrap used for wrapping
of sandwiches and other foodstuffs. This type of covering or
coating is suitable for the PHS in pellet, and powder or granule
form. In a further alternate, the liquid impervious material may be
provided as a smaller capsule or container in which the PHS 16, in
pellet or powder or granule form is contained, the container being
made of material that ignites at a temperature at or below the
temperature generated by the exothermic reaction between the first
and second parts of the ignition system. Such containers or small
capsules may be in the form for example of capsules used for
medicines.
[0068] In one example a water proof coating is provided by dipping
pellets 16 into a liquid bath of a solvent or solvent mixture and
subsequently removed to allow drying of the liquid leaving a water
proof coating on the pellet. A solvent mixture of shellac and
methylated spirits has been found effective in forming the water
proof coating. The mixture is of ten to thirty parts methylated
spirits to one part shellac, with a mixture ratio of twenty (20)
parts methylated spirits to one part shellac being particularly
effective.
[0069] Present ignition system comprises potassium permanganate 18,
and glycol which, when mixed cause an exothermic reaction
generating heat sufficient to ignite the thermite. However
alternate two part chemical ignition systems may be used provided
they generate sufficient heat to ignite the PHS. It is believed
that the heat required for this is at least 600-700.degree. C.
[0070] The capsule bodies 14 comprise a substantially planar bottom
wall 20 and a frusto-conical side wall 22. The side wall 22
decreases in diameter in a direction from an opening 24 of the
capsule body 14 toward the bottom wall 20. Once the PHS 16 and
first part 18 of the ignition system have been deposited into the
capsule body 14 through the opening 24, a seal 26 is placed across
and sealed over the opening 24. The seal 26 is typically in the
form of a thin film of plastics material. The material may be clear
or translucent. Thus each capsule 10 comprises a single sealed
compartment containing one part of the two part ignition system and
a PHS 16. The second part of the two part ignition system is
complete separate from the capsule 10 and remains remote from the
capsule 10 until it is desired to initiate a capsule.
[0071] A circumferential lip 28 is formed about the opening 24 of
the capsule 10 and lies in a plane substantially parallel to a
plane containing the bottom wall 20. The seal 26 is adhered or
otherwise attached to the lip 28.
[0072] In order to form the flexible belt 12, adjacent capsules 10
are joined by coupling 30. The couplings 30 extend in a plane
containing a lip 28. The couplings 30 are formed integrally with
and of the same material as the capsule body 14 and have the same
thickness as the side wall 22 and the lip 28.
[0073] In use, the incendiaries 10 may be provided in the form of
flexible belts 12 wound into reels which may then be fed into a
dispenser to form an overall incendiary system. The incendiary
system feeds the capsules sequentially to the dispenser which
injects a quantity of the second part of the ignition system (e.g.
glycol) held in a storage vessel or tank into each capsule 10
through the seal 26 and severs or breaks the coupling 30 to enable
separate dispensing of the incendiaries 10. During this process a
needle may be used to inject the glycol into the capsules 10, where
the need is controlled to penetrate into the capsule to a depth
that does not reach the PHS 16. The first and second parts of the
ignition system chemically react to generate heat sufficient to
subsequently cause ignition of the PHS 16. When dispensing the
incendiaries 10 from an aircraft, the capsules are dispensed from a
height and contain quantities of the first and second parts of the
ignition system such that the capsules will reach the ground prior
to the ignition system generating sufficient heat to ignite the PHS
16 so that the PHS 16 ignites and burns or combusts when the
capsule 10 reaches the ground.
[0074] Modifications and variations to the described embodiments of
the present invention that would be obvious to a person of ordinary
skill in the art are deemed to be within the scope of the present
invention the nature of which is to be determined from the above
description and the appended claims.
* * * * *