Note: Descriptions are shown in the official language in which they were submitted.
CA 02211967 2000-11-09
DESCRIPTION
This invention relates generally to novel and advantageous improve-
meats in campfire pits. It is common, in devices for generating warmth and
providing cooking heat found at most campgrounds, to consist of an elevated
metallic box mounted onto a post into which firewood is burnt. A tilting
grille
is normally provided for cooking purposes. Another type commonly found is
an open earthen dug-out, surrounded with rocks which contains the campfire to
prevent its spread. Sometimes, these rocks are substituted with a metallic
ring,
10 such as a used farm tractor's or truck's rim. Yet another type is the
classical
open-faced fireplace constructed of rocks or bricks and mortar.
Installations of these types are, however, inefficient because:
1) Their permanent setting may interfere with the movements of the
campsite user and the site's setting. This is owing to the diversity in the
camping layout which is dependent on the mode of transportation and type of
camper utilized, or type and number of tents pitched onto the site;
20 2) Most do not offer warmth at the foot level due to their elevation
from the ground;
3) All are permanent fixtures which cannot be relocated with changing
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CA 02211967 2000-11-09
winds, yielding smoke discomfort especially why directed towards the
camper/trailers, tents, or picnic tables;
4) Most do no oiler cleanliness, as ashes may be blown in and around
the campsite by gusts of wind;
5) Most do not oiler an efficient and clean burn due to the lack of
combustion air;
10 6) Most do not offer wind protection from any direction, which may
create hazards with ambers and sparks being blown away;
7) All make it difficult and messy to clean out the ashes;
8) None are portable, capable of storing and transporting kindling, or
be removed from the site without leaving a heap of unsightly ashes;
9) Nee may be used as an ulterior application out-of season.
20 We have found that these disadvantages may be overcome by
providing a portable cylindrical metallic tub, open at the top, with
perforations
along its circumference. The purpose of these holes is to provide natural
draft
openings for combustion air. This tub may be fitted with either a lip at the
top,
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or one or more handles securely fastened onto its side. This lip, or the
handles,
make it easier to grasp and transport the tub, especially if filled with
kindling.
A vertical center post may be fastened at the bottom of the tub and provide a
leaning medium for fire logs when arranged in a teepee fashion. This post,
coupled with the combustion air holes, significantly improve the burning
effici~cy, offer a hotter and cleaner burn, and minimize smoke. This open top
circular tub, with its side perforations limiting the amount of combustion
air,
serves as an ideal shield against wind from any direction, and minimizes carry-
over of sparks. There is no need for openings at the bottom of the tub, thus
10 ambers and ashes are contained within the tub. Ashes are conveniently
disposed by inverting the tub into a respective container.
Because this tub rests on the ground, the radiant heat is generated at
foot level, where it is sometimes most needed. Sitting or standing close-by is
also comfortable, due to the cleaner and more efficient burn; thus less smoke.
This portable tub may be rendered semi-permanernt if an annulus is
fastened onto the tub, with one end of a chain or steel cable hooked into said
annulus, the other end fastened to a tree, or to a sunken post. This is for
the
20 sole purpose of theft prevention. If the sunken post is the original
support of
the now decommissioned metallic box campground fireplace, this box may now
be conveniently used to store firewood. A tarp wrapped around this box with
bungee cords may assure readily available dry wood.
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Even in a semi-permanent arrangement, the tub can be relocated within
the radius of its restraints. If the wind does create a problem with some
smoke,
the tub can be relocated, eliminating downwind discomforts or hazards. The
tub may also be moved to prevent occasional sparks from damaging camping
gear.
This natural-draft portable campfire pit may also be moved about the
site to accommodate versatility in the camping layouts.
10
A more permanent arrangement would consist of a sunken metal post,
with the tub's hollow centre column inserted over said post. This would allow
fastening the tub onto the sunken post, as well as elevating the fireplace if
solely used for cooking purposes, such as in day-use campgrounds.
Additionally, a removable grille may be fitted onto the top of the tub
for cooking purposes, such as boiling water in a kettle, cooking with a cast
ire
skillet, and other uses.
20 Further, when transporting this container to and from campsites, and
for the purpose of storing dry kindling, a tarp may be draped over and
fastened
onto the tub, with one end of one or more bungee cords attached to the tarp,
and the other end hooked into the combustion air holes.
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Finally, and especially in northern climates, ice the camping seas
comes to a close, this tub can still be used as an interior container for
storing,
and disposing of, ashes. Simply by inserting a bladder inside the tub, thus
covering the combustion holes, this comainer may store, without seepage, ashes
from wood burning facilities which provide heat and comfort inside the home.
The conveniently located handles, much the same as for campsite use, render
the transporting of these ashes quite easy, and the disposing very clean, by
means of inverting the said tub.
10
It is an overall aim of the present invention to provide a campfire pit
having an improved design over existing facilities or devices.
It is also an aspect of this invention to provide a more efficient, and
cleaner burning, device over present-day installations, using sound
engineering
practices and knowledge.
Yet another object of the present invention is to procure a portable
campfire unit which may offer protection from blowing smoke and sparks,
20 without rearranging the campsite layout.
Still another aim of the present invention is to supply a container for
storing the combustion by-products, mainly ash, and a safe and easy means of
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disposing same.
Another advantage of this invention is to offer a portable means of
storing and transporting firewood, burning firewood, and storing, transporting
and disposing of ashes, all within the same container.
Finally, one last objective of this invention is to offer a product which
can be easily and inexpensively manufactured.
Other objects and advantages of the present invention may present
themselves from the following description when considered with the
accompanying drawings, in which:
Figure 1 is an elevation view of one embodiment;
Figure 2 is a top plan view partly in secti~ of another embodiment,
having two carrying handles and a centre post;
Figure 3 is an elevation partly in section showing another embodiment,
having two carrying handles and a tipping handle, as well as a centre post,
illustrating how kindling can be stored inside the embodiment;
Figure 4 illustrates the natural draft principle of this embodiment;
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Figure 5 shows an annulus fastened onto the side of the embodim~t,
from which a chain or a steel cable may be attached, and strung to an adjacent
sunken post, ~to which it is fastened as an anti theft measure;
Figure 6 demonstrates how the fire can be stoked with the fire pit in
use, by means of a hinged grille, also fitted with handles, which may be swung
open on either side, with cookware still in place;
10 Figure 7 depicts an elevati~ partly in secti~ of a typical site
arrangement, with the embodiment mounted onto a long sunken post, and the
tub's hollow centre column fastened rigidly onto said post, affording a higher
elevation of the cooking surfaces;
Figure 8 shows yet another typical site arrangement with an existing
elevated metallic box campground fireplace, with the embodiment fastened to
the fireplace's upright post;
Figure 9 illustrates how ashes are removed from the embodiment;
20
Figure 10 is an elevation view of the embodiment, with a protective
tarp draped over the tub, for the storage of dry kindling, and;
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Figure 11 illustrates the embodimecit fitted with an internal bladder to
contain ashes.
Referring now in more detail and by reference characters to the
drawings which designate id~tical or corresponding practical embodim~ts of
the invention throughout the several views, Fig. 1 illustrates a cylindrical
metallic tub or container 10, open at the top, with perforations 11 arranged
in
random or selectively positioned along the tub's circumference. At or near the
top of the tub 10, is formed a neck or constriction 12, which then extends
10 radially in an outwardly and upwardly fashion to the very top of the tub,
thus
forming a ridge, or a lip 13. This lip offers a grasping medium for which the
tub may be manually carried. The bottom 25 of the tub is totally free of
openings. The top of the tub is fitted with a removable grille 14, which
purpose will be disclosed later in this description.
Referring now to Fig. 2, which shows a top view of the embodiment,
the tub 10 is now fitted with two carrying handles 20 on each side. The
handles 20 each comprise of a wooden dowel 21 or metallic spring 21-a
fastened to two metallic side rails 22 by means of screws 23, rivets, or other
20 like fasteners. The purpose of the wooden or metallic spring handles 21 is
not
to store any radiant heat which may be damaging to the bare hands. The
metallic side rails 22 are in turn radially and rigidly attached to either the
side
of the tub 10, near the top, or under the lip 13, i.e to the neck 12. Fasting
of
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the rails 22 to the side of the tub 10 are also by fasteners 23, or by fusion
welding. The removable metallic grille 14 is also partially shown resting on
top of the tub 10. A m~allic centre post 24 may also be extending in an
upright fashion from the bottom 25 of the tub, also rigidly fastened. Finally,
Fig. 2 illustrates how the cylindrical side of the tub 10 assists in
redirecting a
wind pattern 28 around the tub, thus yielding an aerodynamic profile 29 to the
tub.
Referring further to Fig. 3, which illustrates an elevation view partly in
section of yet another embodiment, whereby kindling 30 is stored within the
container 10. Said kindling 30 is neatly stacked against the centre post 24
for
carrying purposes. This embodiment is also fitted with two carrying handles
located at or near the top of the tub 10, and an additional tihing handle 26
comprising the same components as handles 20, i.e. a wooden or metallic
spring handle 21, attached onto side rails 22 by means of fasteners 23. The
side rails 22 are in turn attached to the side of the tub 10 with screws 23 or
other like devices, or by means of fusion welding. The purpose of the tilting
handle 26 is to invert the container to quickly remove the kindling 30, among
other uses, which shall be disclosed later in this description.
20
Figure 4 illustrates the conceptual principle of the natural draft theory,
as applicable to this embodiment. For illustrative proposes, a partial cut-
away
view is presented for clarity. The kindling 30, arranged in a teepee fashion
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against the central post 24, offers ample air movement between the individual
pieces of kindling. Once the kindling 30 is ignited, the flame 31 heats up the
surrounding air 32 inside the tub 10. This warm air 32, being less dense than
the external or ambient air 33, thus rises due to buoyancy. The displaced air
32 rising from the combustion process needs to be replaced by the outside air
33, thus creating an air velocity, also known as an air current 34. This
combustion process is regulated by the amount of external air 33 which may
pass through the perforations, or combustion air holes 11, as the air velocity
34
is dependealt on the size of the holes. Therefore, the wind velocity 28 as
shown
10 in Fig. 2 is not only deflected from the curvature of the tub 10, but
penetration
through the combustion air holes 11 is also limited. The end results are that
even with a wind velocity 28 higher than the displaced air velocity 34, the
area
of the combustion air holes 11 is negligible compared to the overall area of
one
side of the tub. Therefore, the velocity of the hot air 32 exiting the tub
remains
relatively constant, with ash and spark entrainment 35 being minimized. This
results in a more controlled and cleaner combustion of the firewood 30, with
relatively little smoke 36.
With fireuvood burning inside the tub, the grille 14 d~icted in Figures
20 1 and 2, when mounted onto the top of the tub 10, offers a means of
reposing a
kettle for boiling water, barbecuing meat or poultry, cooking with a cast iron
skillet, or other purposes. Although Figures 1 and 2 illustrate a grille
covering
the whole of the top surface of the tub, a partial grille may also be
utilized,
CA 02211967 2000-11-09
enabling stoking of the fire while cooking.
Even if smoke, ashes, or sparks do create a hazard, or discomfort, the
tub 10 can be moved to a safer locale by means of one of the handles 20 which,
if they are wooden or fashioned from a metallic spring 21, may be safely
touched if the person wears protective gloves.
Figure 5 illustrates an annulus 15 rigidly fastened to the side of the tub
10. A chain 16, or any other like device, having one end hooked into this
annulus 15, and the other end of said chain 16 also hooked to a second annulus
15, serves as an anti-theft device for securing the tub 10 onto the campsite
when attached to a sunken post 17.
Figure 6 demonstrates another embodiment with a split grille 14
fastened to the tub 10 by means of hinges 38. The purpose of the hinges is to
permit a user to stoke the fire with wood 30 simply be swinging part of the
grille 14. The grille 14 is fitted with like handles 37 as described
previously,
fastened by means of side rails 22. Stoking of the fuel can be done without
disturbing the cookware 39, which makes no part of this embodiment.
Figure 7 depicts yet another view of a typical site arrangement, shown
in a partly sectional elevation. The campfire pit 10 is now mourned in an
elevated position by inserting the hollow centre column 24 over a longer
sunken
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post 17 than shown in Figure 5. This affords a higher elevation of the cooking
surfaces. This embodiment illustrates a single lifting handle 20, and a
tilting
handle 26. A chain 16 attached to the tub's annulus 15 and another ring 15
secures the tub to the post 17. Additionally, the tub 10 can be secured to the
post by means of a faster 18 at the top of the center column 14. Removing
the fastener 18 allows the caretakers to remove the tub from the post, and to
tilt
the ashes as subsequently shown in Figure 9. The length of the chain 16 is
sui~cier~t for this purpose.
10 Figure 8 shows a typical campground setting and how the tub 10 may
be attached to an existing post 17 by means of fasting one end of a chain 16
and the annulus 15. In this case, the post happens to be the support for a
previous metallic-box campfire pit 41 on the campsite. This box 41, which
makes no part of this invention, is now utilized to store kindling and
firewood
30. Figure 8 also shows a variation in the embodiment's side perforations,
these being shown as a wire meshing 19.
The superior burning efficiency of the firewood results in a cleaner
burn, whereby all that remains in the tub are essentially ashes. Figure 9
20 illustrates how the ashes 45 may be effectively removed by inverting the
tub 10
by means of grasping one of the top carrying handles 20, and the lower tipping
handle 26 (as shown in Figures 7 and 8). These ashes 45 may the be
confined to a proper disposal containment 4Z, which makes no part of the
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embodiment. The chain 16 which acts as a constraint in Figure 8 may be
substituted with a wire rope 16-a, also double-ended with annuli 15. The
kindling 30 stored in the metallic box 41 may be further protected from the
elements if draped with a tarp 43.
Figure 10 shows how a tarp 43 may be draped over the tub 10 for
storing dry kindling against the elements of nature. Bungee cords 48 which
have one end fastened to grommets 44 in the tarp, are strung down along the
side of the tub and attached to the tub by means of hooks 49 inserted into the
tub's combustion air holes 11.
Figure 11 illustrates how an internal bladder 46 may be fitted into the
tub 10 and held in place by means of a sewn elastic 47 str~ched around the
constriction 12 of the tub. This bladder effectively seals the combustion air
holes 11 such that ashes 45 may be cleanly stored inside the tub. This is most
convenient for long term storage of ashes which are removed from conven-
tional wood-fired furnaces nonrnally found in the colder climate homes.
Cleaning of these furnaces and/or fireplaces must be undertaken at regular
intervals, and the storage capacity of the tub is su~cient for a number of
successive clean-outs. Carrying and disposing of these ashes are done in a
similar fashion as previously outlined in this disclosure.
Thus it has beg described and illustrated a novel and unique campfire
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pit burner which fulfills all of the associated objectives and advantages
sought
thereof.
It must be understood, although it is not shown, that other appendages
may be incorporated to this embodiment with no deviations from the stated
embodiment's intended purposes, these appurtenances serving either useful or
cosmetic means:
a) Legs may be rigidly fastened to the bottom of the embodiment to
10 provide an air space serving as a heat shield to the ground;
b) The same purpose may be achieved if the embodiment is laid flat
directly onto a heat-resistant surface, such as a concrete patio pad;
c) Yet another heat-shielding medium may be in the form of
interlocking bricks stacked radially along the perimeter of the
embodiment, with allowance for combustion air holes;
d) And the overlying grille may be substituted or overlaid with a wire
mesh screen to further prevent spark carry-over.
It should also be understood that any changes, modifications,
20 variations, or other applications or uses will become apparent to those
skilled
in the art upon consideration of this disclosure and its associated drawings.
It
should further be understood that all such changes, modifications, variations,
or any other applications which do not depart from the scope and spirit of the
14
