[0001] The present invention relates to a portable collapsible stove.
[0002] Portable collapsible stoves are well known and many different types have been proposed.
Such stoves can be easily carried in a backpack or the like, and may be known as 'single'
stoves in that they are arranged to heat food or liquid in a single container. Some
of the prior art stoves comprise some sort of collapsible metal frame arranged to
provide a fuel locating region, and supports to support a container above the fuel.
It has been previously proposed to provide a portable collapsible stove formed from
rigid metal sheets hinged together to form an outer windshield and an inner fuel support
platform. Such prior proposals are typically relatively heavy, noisy and dirty to
use, and provide inefficient, uncontrolled combustion.
[0003] We have provided an early solution to the above problems with the portable collapsible
solid fuel stove described in our European patent application
EP 1957870 of 18 July 2006.
[0004] The present invention stems from significant developments of our above stove, and
from work in providing an improved solution to the above problems.
[0005] According to a first aspect of the invention there is provided a portable collapsible
stove, the stove being formed from sheet laminate material, the laminate material
comprising at least one planar sheet of a metal material adhered to at least one planar
non-metallic substrate, the stove comprising a plurality of side walls formed from
the sheet laminate material, adjacent side walls being joined together such that the
side walls together define a tube one end of which comprises a base which rests in
use on the ground and an opposed end of which comprises a mouth to at least partially
receive, and support, in use a container or the like, the stove further comprising
a fuel support platform also formed from the sheet laminate material, the fuel support
platform being located inside the tube at a position spaced from the base of the tube,
with the outer periphery of the fuel support platform being fastened to the side walls,
at least one air inlet aperture being provided in a side wall below the fuel support
platform, at least one exhaust aperture being provided in a side wall above the fuel
support platform, the stove being collapsible from an operational condition in which
the side walls define the tube and the fuel support platform extends across the tube,
to a collapsed, substantially flat condition in which the side walls and fuel support
platform are substantially parallel. The stove may further comprise at least one aperture
shield arranged to extend across each inlet and exhaust aperture to block light emitted
through each aperture in use. The or each aperture shield may comprise a vent spaced
from the aperture and operative to allow gas flow through the aperture.Preferably
all of the apertures are covered by at least one of the shields. Each of the shields
may cover only one, or more than one, of the apertures.
[0006] Preferably each aperture shield comprises an oblong flap fixed to the respective
wall of the stove below the inlet or exhaust aperture in question. The upper part
of the flap may not be fastened to the respective wall, and so may define a vent in
communication with the inlet or exhaust aperture in question.
[0007] Preferably the or each flap is movably mounted on the respective wall so as to be
movable from an operational condition in which the upper end of the flap is distal
from the respective wall, to a partially collapsed condition in which the upper end
of the flap is adjacent the respective wall.
[0008] Preferably the side margins of the flap are fastened to the respective wall by way
of pleated sides which allow the flap to be moveable between the operational and collapsed
conditions.
[0009] Preferably the sheet laminate material further comprises an anti-reflecting coating.
The coating may be provided on a surface of the material which forms an outer surface
of the stove in use. The surface may be formed by the metal foil, or may be formed
by the non-metallic substrate. The anti-reflecting coating may comprise matt black
paint, or it may comprise PTFE, or it may comprise graphite.
[0010] Preferably the walls are fastened together using stitching. The stitching may incorporate
a fire retardant thread. The fire retardant thread may comprise a glass fibre thread.
The fire retardant thread may be impregnated and/or coated with PTFE and/or graphite.
The graphite renders the thread black and therefore of low visibility. Preferably
the fuel support platform is fastened to the tube using a fire survivable fastening
means.
[0011] Preferably the fire survivable fastening means comprises stitching incorporating
a fire retardant thread.
[0012] The fire survivable fastening means may comprise a metallic or non-metallic material.
The fire survivable fastening means may comprise a staple or rivet for example, or
may comprise adhesive. Combinations of any of stitching, rivets, staples and adhesive
are envisaged as may be required to meet structural, manufacturing or cost based objectives.
[0013] Preferably a pull tab is provided on the underside of the fuel support platform,
whereby a user can pull the pull tab to assist with moving the stove from the collapsed
condition to the operational condition.
[0014] The side walls may comprise side margins. Preferably the side margins of each wall
are bent outwardly from the plane of the wall to define a side wall fin, adjacent
side wall fins being fastened together.
[0015] The non-metallic substrate of the sheet of laminate material may comprise a glass
fibre mat. The non metallic substrate may be impregnated and/or coated with PTFE.
[0016] According to a second aspect of the invention there is provided a portable collapsible
stove, the stove being formed from sheet laminate material comprising a planar non-metallic
substrate and two planar sheets of a metal foil material adhered to opposite sides
of the substrate, , the stove comprising a plurality of oblong walls formed from the
sheet laminate material, each wall comprising a pair of side margins, the side margins
of adjacent walls being joined together such that the walls together define a tube
one end of which comprises a base which rests in use on the ground and an opposed
end of which comprises a mouth to at least partially receive, and support, in use
a container or the like, the stove further comprising a fuel support platform also
formed from the sheet laminate material, the fuel support platform being located inside
the tube at a position spaced from the base of the tube, with the outer periphery
of the fuel support platform being joined to the side walls inside the tube, at least
one air inlet aperture being provided in a side wall below the fuel support platform,
at least one exhaust aperture being provided in a side wall above the fuel support
platform, the structure of the sheet of laminate material, the fastening of the side
margins of adjacent side walls and the fastening of the outer periphery of the fuel
support platform being arranged such that the stove can be collapsed from an operational
condition in which the sidewalls define the tube and fuel support platform, to a collapsed,
substantially flat condition in which the walls and fuel support platform are substantially
parallel.
[0017] According to a third aspect of the invention there is provided a portable collapsible
solid fuel stove, the stove being formed from sheet laminate material comprising a
planar non-metallic substrate and at least one planar sheets of a metal foil material
adhered to the substrate, , the stove comprising a plurality of oblong walls formed
from the sheet laminate material, each wall comprising a pair of side margins, the
side margins of adjacent walls being stitched together such that the walls together
define a tube one end of which comprises a base which rests in use on the ground and
an opposed end of which comprises a mouth to at least partially receive, and support,
in use a container or the like, the stove further comprising a fuel support platform
also formed from the sheet laminate material, the fuel support platform being located
inside the tube at a position spaced from the base of the tube, with the outer periphery
of the fuel support platform being stitched to the side walls inside the tube, at
least one air inlet aperture being provided in a side wall below the fuel support
platform, at least one exhaust aperture being provided in a side wall above the fuel
support platform, the structure of the sheet of laminate material, the stove being
collapsible from an operational condition in which the sidewalls define the tube and
fuel support platform, to a collapsed, substantially flat condition in which the walls
and fuel support platform are substantially parallel.
[0018] According to a fourth aspect of the invention there is provided a sheet of laminate
material comprising at least one planar sheets of a metal foil material adhered, using
fire retardant adhesive, to at least one planar non-metallic substrate, the resulting
laminate sheet being fireproof such that the structural integrity of the resulting
laminate sheet is stable when subject to flame temperatures of up to 1000°C, the resulting
laminate sheet also being flame retardant such that the integrity of the resulting
laminate sheet is stable when subject to repeated exposure to flames.
[0019] Other aspects of the present invention may include any combination of the features
or limitations referred to herein.
[0020] The present invention may be carried into practice in various ways, but embodiments
will now be described by way of example only with reference to the accompanying drawings
in which:
Figures 1a and 1b are perspective views of two examples of a sheet of laminate material used to form
a portable collapsible stove in accordance with the present invention;
Figure 2 is a perspective view from the top, front and one side of a portable collapsible
stove in accordance with the present invention;
Figure 3 is a plan view of the stove of Figure 2;
Figure 4 is a perspective view of the stove of Figures 2 and 3 in a collapsed condition;
Figure 5 is a perspective sectional view of the stove of Figures 2 to 4, taken on line A-A
of Figure 2, illustrating the inlet and exhaust gas flow paths;
Figure 6 is a perspective view from the top, front and one side of another portable collapsible
stove in accordance with the present invention;
Figure 7 is a plan view of the stove of Figure 6;
Figure 8 is a perspective view of the stove of Figures 6 and 7 in a partially collapsed condition;
Figure 9 is a plan view corresponding to Figure 8;
Figure 10 is a perspective view from one side of the stove of Figures 6 to 9 in a fully collapsed
condition;
Figure 11 is a perspective from the other side of the stove of Figures 6 to 10 in a fully collapsed
condition;
Figure 12 is a perspective sectional view of the stove of Figures 6 to 11 taken on line B-B
of Figure 6, illustrating the inlet and exhaust gas flow paths;
Figure 13 is a perspective sectional view of the stove of Figures 6 to 12 taken on line C-C
of Figure 6, illustrating the inlet and exhaust gas flow paths;
Figure 14 is a perspective sectional view of a modified stove in accordance with the present
invention;
Figure 15 is a perspective sectional view of the modified stove of Figure 14 in use with a
gas burner;
Figure 16 is a perspective sectional view of the modified stove of Figure 14 in use with a
liquid fuel burner; and
Figure 17 is a perspective sectional view of the modified stove of Figure 14 in use with a
gel fuel container.
[0021] Referring initially to Figure 1a a first example sheet of laminate material 1a comprises
a non-metallic substrate 3 sandwiched between two sheets of metal foil, which in this
case are aluminium foil material 5, 7, though other metal materials can be used. The
aluminium foil sheets 5, 7 are glued to the substrate 3 by respective adhesive layers
9, 11.
[0022] In a preferred example, the non-metallic substrate 3 comprises a plastic covered
glass fibre mat. The substrate 3 may be impregnated and/or coated with PTFE.
[0023] The adhesive layers 9, 11 are formed from a single or a composite material including
a fire retardant adhesive.
[0024] The laminate sheet 1 is thus five-ply in this example.
[0025] Referring to Figure 1b, another example laminate sheet 1b has similar features to
the sheet 1a described but is three-ply in this example. The sheet 1b comprises a
substrate 3 to which a single aluminium foil sheet 5 is glued by adhesive layer 9.
[0026] It will be appreciated that the laminate sheet can comprise any number of plies as
required to provide the desired flame retardant and structural properties.
[0027] In a preferred embodiment, the total thickness of the laminate sheet 1a, 1b is in
the range 10 to 500 µm. The thickness of the substrate 3 is in the range 5 to 200
µm. The thickness of the or each aluminium foil sheet 5, 7 is in the range 5 to 200
µm.
[0028] The resulting laminate sheet 1a, 1b displays flame retardant properties and will
withstand persistent flame temperatures of up to 1000°C for, for example, 20 to 40
minutes, and still maintain its structural integrity. In the example portable stove
described below the exhaust gas temperatures are approximately in the range 200°C
to 400°C.
[0029] The resulting laminate sheet 1a, 1b exhibits sufficient rigidity that a container
of liquid can be supported by the sheet 1a, 1b without the sheet 1a, 1b deforming,
bending or collapsing, when in the form of the expanded stove described below, but
is sufficiently flexible that the sheet 1a, 1b can be bent or folded without distorting
or deforming as a sheet of aluminium foil would normally do. The sheet 1a, 1b retains
these properties under very high operating temperatures as described above.
[0030] The introduction of a non-metallic substrate of plastic coated mat 3, and adhesive
layers 9, 11, allows the resulting laminate sheet 1a, 1b to be both structural and
articulate in a manner not possible with a metal foil. Thin metal foils normally permanently
deform and fatigue when bending occurs, taking the material beyond its ultimate tensile
strength by simple deformation pressures and movements. These changes are typically
irreversible. The use of the substrate 3 allows the conformal shape of the sheet 1a,
1b to be maintained, and the properties of the metal in a high temperature environment
to be exploited.
[0031] The laminate material 1a, 1b is therefore flexible, beyond the natural capability
of the metal foil on its own. We have used the flexible nature of the resulting laminate
material 1a, 1b as part of the advantageous stoves described below.
[0032] The laminate material 1a, 1b is capable of significant cycling without fatigue failure.
Additionally, because of the cycling through the high temperatures endured during
use, we have determined that the heat cycling adds a stress relieving aspect to the
sheet 1a, 1b, preventing work hardening by normalising the aluminium material each
time the stove is used. The sheet 1a, 1b therefore remains more flexible than would
be expected from a cold worked metal material when repeatedly folded.
[0033] Referring additionally to Figures 2 and 3, a portable collapsible stove 13 has its
primary components and structure formed/defined entirely from laminate sheet, such
as, for example, the laminate sheets 1a or 1b described above.
[0034] The stove 13, in this example, comprises six planar oblong side walls 15 of the laminate
sheet. The side margins of each side walls 15 are bent beyond 90° relative to the
plane of each side wall 15, and each side margin is fastened to the adjacent side
margin of the adjacent side wall 15 to form radially outwardly projecting fins 18.
The side margins are fastened together using fire retardant stitching 19. Stitching
19 uses, in this example, a high temperature resistant PTFE coated thread formed from
glass fibre. The thread may also be impregnated or coated with Graphite to render
the thread low visibility.
[0035] The top and base margins 21, 23 of each side wall 15 are also stitched 25, 27 respectively
to resist delamination of the laminate sheet in use.
[0036] When so fastened, the side walls 15 together define an upstanding fire resistant,
high temperature resistant tube 29 one end of which functions as a base 31 which rests
in use on the ground, and the opposite end of which defines a mouth 33 into which
a container (not shown) is placed in use of the stove 1. One of the side walls 15A
is provided with an oblong cut-out 35 to receive a handle of the container. Because
the side walls 15 are formed from the laminate sheet, the side walls 15 can to some
extent flex around, and conform to, the shape of the container such that the side
walls 15 snugly engage the container to resist air flow between the side walls 15
and the container. The structure of the laminate sheet, and the resulting tube structure,
provides sufficient strength and rigidity in compression, and resistance to bending
and folding, to support the container when filled with liquid.
[0037] The stove 13 further comprises a fuel support platform 41 formed from the laminate
sheet and being of generally hexagonal shape when viewed in plan, to match the generally
hexagonal cross section of the tube 29, as defined by the six side walls 15. The periphery
of the fuel support platform 41 is fastened to the side walls 15 inside the tube 29
by fire retardant stitching 43 as described above. The fuel support platform 41 is
inclined inside the tube 29 such that the part of the platform 41 beneath the cut-out
35 is higher up the tube 29 than the opposed part of the platform 41 fastened to side
wall 15B.
[0038] The fuel support platform 41 is spaced from the base 31 of the tube 29 and in this
example is located about a quarter of the way up the tube 29. An air inlet manifold
51 is therefore defined between the ground on which the tube 29 rests in use, and
the underside of the fuel support platform 41. The air inlet manifold 51 is provided
with two external air inlet apertures 53 formed in opposed side walls 15C, 15D. The
fuel support platform is itself provided with two internal air inlet apertures 55.
The air inlet apertures 53, 55 form a controlled air inlet path to the region above
the fuel support platform 41, that is, the region in which the fuel is placed in use.
[0039] The stove 13 is further provided with four exhaust gas outlet apertures 57, located
above the fuel support platform 41. When the container is sealingly located in the
mouth 33 of the tube 29, a fixed volume combustion chamber is defined between the
underside of the container and the top of the fuel support platform 41 from which
exhaust gas can only exit via the exhaust gas outlet apertures 57.
[0040] An access aperture 60 with closing tab 61 is provided on side wall 15b and this is
used to allow a suitable ignition source, such as a match or lighter, access to the
combustion chamber 59.
[0041] A tab 63 is provided on the underside of the fuel support platform 41 and this can
be pulled to help expand the stove 13 from the collapsed condition described below.
With particular reference to Figure 4, the stove 13 can be stored/carried in a collapsed
condition wherein the side walls 15 and fuel support platform 41 are folded together
so as to be substantially parallel, the collapsed stove 13 thus being substantially
flat.
[0042] To expand the stove 13, opposed side walls 15, or opposed fins 18 can be gripped
and pulled apart to expand the stove 1 from the collapsed, substantially flat, condition,
to the expanded, substantially tubular condition. The tab 63 on the underside of the
fuel support platform 41 may also be pulled downwardly to pull the fuel support platform
41 from a folded condition, to a planar condition. When in the expanded condition,
the stove 13 is self supporting with the base 31 of the tube 29 resting on the ground,
and the fuel support platform 41 acting as a brace across the tube 29to resist bending
or folding of sidewalls 15.
[0043] When in the expanded condition, and with reference also to Figure 5, fuel, such as
a piece of solid fuel 70, is supplied to the fuel support platform 41 and ignited
using a suitable ignition source. In this example, solid fuel 70 is simply placed
on the due support platform 41. Combustion air, as referenced by arrows C, is drawn
into the combustion chamber 59 via the air inlet apertures 53, 55 and the air inlet
manifold 51. The size, number and location of the air inlet apertures 53, 55, and
the volume of the air inlet manifold 51, may be calculated to provide the volumetric
air flow required for the desired fuel.
[0044] Once the fuel is ignited, or before the fuel is ignited, the container is placed
into the mouth 33 of the tube 39 and this defines the fixed volume combustion chamber
59. Exhaust from the combustion process, as indicated by arrow E, exits the combustion
chamber 59 in a controlled manner via exhaust outlet apertures 57. Again, the volume
of the combustion chamber 59, and the size, shape, location and number of exhaust
outlet apertures 57 may be calculated to provide the required burn characteristics.
Heat rises onto the container as per arrow H.
[0045] Referring additionally to Figures 6 to 9, a modified stove 63 comprises similar features
to the stove 13 described above, like features being given like references.
[0046] Modified stove 63 further comprises low visibility features which render the stove
63 more difficult to see both during transit, and in use. Being of low visibility
is a useful feature particular in military applications where the user of the stove
may not wish to give away their position. Ordinarily the flames and glow from the
burning fuel may be visible through the exhaust apertures 57. Furthermore, the aluminium
foil of the sheets 1 of laminate material 1 would reflect any ambient or directed
light.
[0047] Thus, the sheet of laminate material 1 of stove 63 comprises an additional anti-reflective
coating on the external surfaces of the aluminium foil sheets 5, 7. The anti-reflective
coating may comprise a matt black coating for example. The modified laminate sheet
is thus seven-ply in this example.
[0048] Additionally, the stove 63 comprise aperture shields 65 each of which extends from
the base 31 of the tube 29 towards the mouth 33 of the tube 29. Each aperture shield
65 comprises a flow channel 66 defined by an outer, oblong flap 67 having pleated
sides 69 which extend between the side margins of the flap 67 and a respective side
wall 15 of the stove 63. The bottom of each flap 67 is fastened adjacent the base
31 of tube 29. The top of each flap 67 is not fastened to the side walls 15 and is
provided with a pull tab 71 to enable the top of each flap 67 to be pulled away from
the respective side wall 15. When so pulled, with reference to Figures 6 and 7, each
aperture shield 65 defines a respective flow channel 66 to allow inlet air into the
exterior air inlet apertures 53, and to allow exhaust gas from the exhaust gas outlet
apertures 57. The flap 67 and pleated sides 69 shield the light from the combustion
process from being seen as the flap 67 and pleated sides 69 cover the respective inlet
or exhaust aperture 53, 57.
[0049] With particular reference to Figures 8 to 11, the stove 63 may be collapsed by first
pushing the flap 67 of each aperture shield 65 towards the respective side wall 15.
This collapses each flow channel 66. Opposed side walls 15 can then be pushed together,
and the fuel support platform 41 folded, such that the side walls 15 and platform
41 are substantially parallel with the stove 63 in a substantially flat condition
and the tube 29 is collapsed.
[0050] With reference to Figures 12 and 13, the inlet combustion air and exhaust air flow
paths C, E are as described above with reference to stove 13 except that the exhaust
flows from the exhaust outlet apertures 57, up the channels 66, each channel 66 functioning
as an exhaust flue. The channels 66 also function as inlet ducts to allow inlet combustion
air to flow down the channels 66 and into the inlet manifold via the external inlet
apertures 53.
[0051] A thermally insulated tab or the like may be provided on each flap 67 to enable the
flap 67 to be gripped once the stove 63 has been used, to enable the flap 67 to be
pushed to the collapsed condition. This may be advantageous should the stove 63 need
to be packed away relatively quickly after use, without burning the user's hands or
fingers. The tab may be provided at the top margin of each flap 67.
[0052] A tab or clasp or other retainer may be provided at the top of each flap 67 to engage
with the top of the respective side wall 15 to prevent the flap 67 opening inadvertently
when in the collapsed condition.
[0053] It will be appreciated that any number of side walls 15, inlet apertures 53, 55 and
exhaust apertures 57 may be provided as required.
[0054] Each fin 18 may be provided with a reinforcing element or elements to provide additional
structural strength to each fin 18. The reinforcing element may comprise a strip of
reinforcing material received within a pocket defined by the fin 18. The reinforcing
material may comprise a fold of material folded around the fin 18 or over the top
of the fin 18. The reinforcing material may comprise a metal material such as a tempered
aluminium material for example.
[0055] It is preferred that the stove 13, 63 uses a solid fuel. An example of a solid fuel
used historically is Hexamine although other fuel types are envisaged.
[0056] The stove 13, 63 may also or alternatively be used with gel fuels, ie jelly like
fuels which are typically ethanol based, or liquid fuel stored in a container which
can be placed on the fuel support platform 41. The stove 13, 63 may also or alternatively
use gas or vaporised fuels (such as petrol, paraffin, butane or propane).
[0057] With reference to Figure 14, a modified stove 13, 63 comprises the fuel support platform
41 as above but provided with a burner aperture 72 in which a fuel container or gas/vaporised
fuel burner can be located.
[0058] With reference to Figure 15, a gas burner 73 is located in the burner aperture 72
with the inlet pipe 75 of the gas burner 73 passing into the inlet manifold underneath
the fuel support platform 41 of the stove 13, 63, out through one of the side walls
15 of the stove 13, 63 and is connected to a suitable container (not shown) of gas/vaporised
fuel.
[0059] With reference to Figure 16, a liquid fuel burner 77, such as a meth burner, is located
in the burner aperture 72.
[0060] With reference to Figure 17, a fuel container 79 is located in the burner aperture
71 and may be filled with gel type fuel for example.
1. A portable collapsible stove, the stove being formed from sheet laminate material,
the laminate material comprising at least one planar sheet of a metal material adhered
to at least one planar non-metallic substrate, the stove comprising a plurality of
side walls formed from the sheet laminate material, the side walls being joined together
such that the side walls together define a tube one end of which comprises a base
which rests in use on the ground and an opposed end of which comprises a mouth to
at least partially receive, and support, in use a container or the like, the stove
further comprising a fuel support platform also formed from the sheet laminate material,
the fuel support platform being located inside the tube at a position spaced from
the base of the tube, with the outer periphery of the fuel support platform being
fastened to the side walls, at least one air inlet aperture being provided in a side
wall below the fuel support platform, at least one exhaust aperture being provided
in a side wall above the fuel support platform, the combination of the structure of
the sheet of laminate material, the joining of the adjacent side walls and the fastening
of the outer periphery of the fuel support platform being such that the stove can
be collapsed from an operational condition in which the side walls define the tube
and the fuel support platform extends across the tube, to a collapsed, substantially
flat condition in which the side walls and fuel support platform are substantially
parallel, the stove further comprising at least one aperture shield arranged to extend
across each inlet and exhaust aperture to block light emitted through each aperture
in use, the aperture shield comprising a vent spaced from the aperture and operative
to allow gas flow through the aperture.
2. The stove of claim 1 wherein each aperture shield comprises an oblong flap fixed to
the respective wall of the stove below the inlet or exhaust aperture in question,
the upper part of the flap not being fastened to the respective wall, and so defining
a vent in communication with the inlet or exhaust aperture in question.
3. The stove of claim 2 wherein the or each flap is movably mounted on the respective
wall so as to be movable from an operational condition in which the upper end of the
flap is spaced from the respective wall, to a partially collapsed condition in which
the upper end of the flap is adjacent the respective wall.
4. The stove of claim 3 wherein the side margins of the flap are fastened to the respective
wall by way of pleated sides which allow the flap to be moveable between the operational
and collapsed conditions.
5. The stove of any one of the preceding claims wherein the sheet laminate material further
comprises an anti-reflecting coating.
6. The stove of claim 5 wherein the sheet laminate material is coated with matt black
paint, or PTFE, or graphite.
7. The stove of any one of the preceding claims wherein the walls are fastened together
using stitching.
8. The stove of any one of the preceding claims wherein the fuel support platform is
fastened to the tube using stitching incorporating a fire retardant thread.
9. The stove of claim 7 or claim 8 wherein the stitching incorporates fire retardant
thread comprises a glass fibre thread coated with PTFE or graphite
10. The stove of any one of the preceding claims wherein a pull tab is provided on the
underside of the fuel support platform, whereby a user can pull the pull tab to assist
with moving the stove from the collapsed condition to the operational condition.
11. The stove of any one of the preceding claims wherein each wall has side margins which
are bent outwardly from the plane of the wall to define a side wall fin that projects
radially outwardly from the tube, adjacent side wall fins being fastened together.
12. The stove of any one of the preceding claims wherein the non-metallic substrate of
the sheet of laminate material comprises a glass fibre mat impregnated and/or coated
with PTFE or graphite.
13. A portable collapsible stove, the stove being formed from sheet laminate material
comprising a planar non-metallic substrate and two planar sheets of a metal foil material
adhered to opposite sides of the substrate, the stove comprising a plurality of oblong
walls formed from the sheet laminate material, adjacent walls being joined together
such that the walls together define a tube one end of which comprises a base which
rests in use on the ground and an opposed end of which comprises a mouth to at least
partially receive, and support, in use a container or the like, the stove further
comprising a fuel support platform also formed from the sheet laminate material, the
fuel support platform being located inside the tube at a position spaced from the
base of the tube, with the outer periphery of the fuel support platform being joined
to the side walls inside the tube, at least one air inlet aperture being provided
in a side wall below the fuel support platform, at least one exhaust aperture being
provided in a side wall above the fuel support platform, the stove being collapsible
from an operational condition in which the sidewalls define the tube and the fuel
support platform is supported inside the tube, to a collapsed, substantially flat
condition in which the walls and fuel support platform are substantially parallel.
14. A portable collapsible solid fuel stove, the stove being formed from sheet laminate
material comprising a planar non-metallic substrate and at least one planar sheets
of a metal foil material adhered to the substrate, , the stove comprising a plurality
of oblong walls formed from the sheet laminate material, each wall comprising a pair
of side margins, the side margins of adjacent walls being stitched together such that
the walls together define a tube one end of which comprises a base which rests in
use on the ground and an opposed end of which comprises a mouth to at least partially
receive, and support, in use a container or the like, the stove further comprising
a fuel support platform also formed from the sheet laminate material, the fuel support
platform being located inside the tube at a position spaced from the base of the tube,
with the outer periphery of the fuel support platform being stitched to the side walls
inside the tube, at least one air inlet aperture being provided in a side wall below
the fuel support platform, at least one exhaust aperture being provided in a side
wall above the fuel support platform, the structure of the sheet of laminate material,
the stove being collapsible from an operational condition in which the sidewalls define
the tube and fuel support platform, to a collapsed, substantially flat condition in
which the walls and fuel support platform are substantially parallel.
15. A sheet of laminate material comprising at least one planar sheet of a metal foil
material adhered, using fire retardant adhesive, to at least one planar non-metallic
substrate, the resulting laminate sheet being fireproof such that the structural integrity
of the resulting laminate sheet is stable when subject to flame temperatures of up
to 1000°C, the resulting laminate sheet also being flame retardant such that the integrity
of the resulting laminate sheet is stable when subject to repeated exposure to flames.