Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TITLE
GAS BURNER ASSEMBLY WITH GAS COLLECTOR AND IGNITER
FIELD OF THE INVENTIONS
The embodiments described and claimed herein relate generally to ignition
systems for
gas-fired barbecue grills. More specifically, some embodiments relate to
corrosion resistant gas
collector for a gas burner igniter.
BACKGROUND OF THE INVENTIONS
Electronic igniters for barbecue grills are well known in the art. Many prior
art igniters,
such as those described in U.S. Patents 4,1241,817 ("the `817 patent") and
6,749,424 ("the `424
patent), use an electric potential to create a ignition spark which travels
between an electrode and
a ground surface. The specific devices described in the `817 and `424 patents
utilize gas
collector boxes, which are disposed in close proximity to a gas burner, for
capturing a
combustible gas/air mixture for an igniter. The igniters of the `817 patent
and `424 patents
generally comprise a gas collector box, an insulated electrode and a ground
wire which is
attached to the collector box, whereby the ignition spark is intended to
travel between the
electrode and the collector box. The electrodes of the `817 and `424 patents
are insulated with a
ceramic sleeve which prevents sparks from occurring at unintended locations.
The collector
boxes of the `817 and `424 patents are constructed from thin-walled sheet
metals.
While the prior art ignitions systems, such as those briefly described above,
provide an
adequate means for igniting barbecue grills, the prior art systems suffer from
previously
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unresolved problems. For example, the prior art collector boxes tend to
quickly degrade or rust,
as they are subjected to extremely harsh conditions in use. By design, the
prior art collector
boxes serve as a ground for the igniter and are disposed in close proximity to
the burners. As
such, the prior art collector boxes are repeatedly subjected to sparks from
the electrode and
extreme heat from the burner tube.
SUMMARY OF THE INVENTIONS
The various embodiments shown and described herein solve at least some of the
above-
mentioned problems of the prior art. For example, one embodiment of a gas
burner assembly
comprises a gas burner, an igniter, an ignition device, and a bracket. The
igniter has a ceramic
body and electrode. The ignition device is configured to generate a spark
between the electrode
and a ground. The gas burner includes at least one port for providing a
combustible gas. The
bracket is configured to position the gas collector portion of the igniter in
close proximity to the
burner port. The ceramic body of the igniter includes a gas collection portion
which is
configured to capture at least some of the combustible gas from the burner
port.
A second embodiment of a gas burner assembly also includes a gas burner, an
igniter, an
ignition device, and a bracket. The gas burner provides a combustible gas
through at least one
port. The igniter includes a body and an electrode. The igniter body is made
from a non-
conductive and heat and corrosion resistant material and has an insulating
sleeve portion and a
hood portion, which are integral. The sleeve portion has a first end and a
second end and the
hood portion depends from the second end of the sleeve portion. The electrode
extends through
the sleeve portion from the first end to the second end, where the electrode
extends outside of the
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sleeve portion into a partially enclosed volume defined by the hood portion.
The insulating
portion of the igniter body is configured to prevent sparks at undesired
locations and the hood
portion is configured to capture at least some of the combustible gas
emanating from the burner.
The ignition device is configured to generate a spark between the electrode
and a ground. The
bracket is configured to position the gas collector portion of the igniter in
close proximity to the
burner port.
A third embodiment of a gas burner assembly comprises a gas burner, an
electrode, a
ground, a hood, and an ignition device. The gas burner provides a combustible
gas through at
least one port. The electrode is positioned above the gas burner and is in
close proximity to the
ground. The hood is disposed at least partially above the electrode and is
made from a ceramic
material. The hood has at least one wall which at least partially encloses a
volume for capturing
at least some of the combustible gas. The ignition device generates a spark
between the
electrode and the ground.
A fourth embodiment of a gas burner assembly is for a barbecue grill. The gas
burner
assembly includes a gas burner tube, an igniter, an ignition device, a
bracket, and a grounded
lead wire. The gas burner tube has a plurality of spaced apart ports for
providing a combustible
gas. The igniter includes a body and an electrode, wherein the body is made
from a ceramic
material and has an insulating sleeve portion and a hood portion. The hood
portion having at
least one wall which at least partially encloses a volume. The sleeve portion
has a first end and a
second end and the hood portion depends from the second end of the sleeve
portion. The
electrode extends through the sleeve portion from the first end to the second
end, where the
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electrode extends outside of the sleeve portion into the volume defined by the
hood portion. The
insulating portion of the igniter body is configured to prevent sparks at
undesired locations and
the hood portion is configured to capture at least some of the combustible gas
emanating from
the burner. The ignition device is configured to generate a spark between the
electrode and a
ground. The bracket is configured to position the gas collector portion of the
igniter in close
proximity to the burner port and includes a first portion for engaging with
the igniter and a
second portion for engaging with the burner tube. The grounded lead wire is
functionally
interconnected with the burner tube, whereby the burner tube is the ground.
Some of the embodiments described above include an insulating sleeve and a gas
collector which are integrally cast from a ceramic or other non-conductive and
heat and
corrosion resistant material. Such a construction provides significant
advantages as compared to
the sheet metal gas collectors of the prior art. For example, the non-
conductive and heat and
corrosion resistant material provides the gas collector with a much longer
life than the metal gas
collector boxes of the prior art. Moreover, because at least some igniter
assembly designs
require a ceramic material for insulating the electrode anyway, the additional
cost for integrally
molding the gas collector is minimal.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, objects, and advantages of the inventions
described and
claimed herein will become better understood upon consideration of the
following detailed
description, appended claims, and accompanying drawings where:
Figure 1 is a perspective view of a first burner tube ignition assembly which
includes a
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first embodiment of a ceramic igniter and a first embodiment of a bracket for
holding the igniter;
Figure 2 is a side view of the same;
Figure 3 is a bottom view of the first embodiment of the ceramic igniter;
Figure 4 is a sectional view of the same;
Figure 5 is a perspective view of a second embodiment of a bracket for holding
an
igniter;
Figure 6 is a perspective view of a second burner tube ignition assembly which
includes a
first embodiment of a ceramic igniter and a third embodiment of a bracket for
holding the
igniter;
Figure 7 is a close up perspective view of the third embodiment of the
bracket;
Figure 8 is a perspective view of a third burner tube ignition assembly which
includes a
first embodiment of a ceramic igniter and a fourth embodiment of a bracket for
holding the
igniter;
Figure 9 is a sectional view of the third burner tube ignition assembly;
Figure 10 is a first close-up perspective view from the front of the fourth
embodiment of
the bracket; and,
Figure 11 is a second close-up perspective view from the rear of the fourth
embodiment
of the bracket.
It should be understood that the drawings are not necessarily to scale and
that the
embodiments are sometimes illustrated by graphic symbols, phantom lines,
diagrammatic
representations and fragmentary views. In certain instances, details which are
not necessary for
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an understanding of the embodiments described and claimed herein or which
render other details
difficult to perceive may have been omitted. It should be understood, of
course, that the
inventions described herein are not necessarily limited to the particular
embodiments illustrated.
Indeed, it is expected that persons of ordinary skill in the art of grill
design may devise a number
of alternative configurations that are similar and equivalent to the
embodiments shown and
described herein without departing from the spirit and scope of the claims.
Like reference numerals will be used to refer to like or similar parts from
figure to figure in
the following description of the drawings.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring first to Figures 1-4, an embodiment of an igniter 30 is shown. The
igniter 30 is
comprised of a body 31 into which an electrode 38 is inserted. The body 31 of
the igniter is
made from a ceramic, such as aluminum oxide (alumina) that has a purity of
approximately 92%-
94% by weight, which is a readily available material. It is contemplated that
other alternative
materials could be used, such as materials which are non-conductive and are
heat and corrosion
resistant.
The body 31 includes an integrally cast gas collector (or hood) portion 32 and
sleeve
portion 34. The sleeve portion 34 is configured to mate with the apertures 45,
47 of the bracket
40, and includes a stop 36 which is configured to engage with the wing 44 to
locate the electrode
38 above the orifices 22, 24. Although the sleeve portion 34 and the apertures
45, 47 as shown
have a square cross section, it is contemplated that the sleeve 34 and
apertures 45, 47 could
comprise other shapes, such as round, square, or any other shape. The gas
collector (or hood)
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portion 32 is positioned directly above the orifices 22, 24 of the burner 20
and includes a single,
continuous, generally parabolic wall which at least partially encloses a
volume. The gas
collector (or hood) portion 32 captures the flammable gas and air thereby
forming a combustible
mixture for the igniter 30 and covers the electrode thereby protecting it from
the elements (gas
barbecue grills are intended to be ignited with the cover open; as such, the
hood protects the
electrode from wind and rain). It is contemplated that the gas collector 32
could comprise other
shapes and/or additional walls. For example, the collector portion 32 could
comprise a
continuous curvilinear wall or multiple planar walls which form a box-like or
other shaped gas
collector.
As better shown in Figures 3 and 4, the electrode 38 extends through the
length of the
sleeve portion 34 from a first end 33 of the sleeve portion 34 to a second end
35 of the sleeve
portion 34. In one embodiment, the sleeve portion 34 of the igniter 30 has at
least two desirable
properties. First, it insulates the electrode to prevent sparks from occurring
at undesirable
locations. Second, because it is heat resistant, it will not melt due to the
extreme heat that is
generated by the burner 20. The first end 33 of the sleeve portion is
sufficiently distanced from
the heat source of the burner 20 whereby the electrode 38 can be connected to
a lead wire 60
which is insulated with a material which has a lower melting temperature than
the sleeve portion
34. Although not shown, it is intended that the lead wire 60 interconnect the
electrode 38 with a
device which is capable of creating an electric potential which is required to
create a spark, such
as a piezoelectric ignition device or other electric ignition devices.
At the second end 35 of the sleeve 34, the electrode 38 extends outside of the
sleeve 34,
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whereby a tip 39 of the electrode 38 is disposed generally within a volume
defined by the gas
collector portion 32. The tip 39 is bent in the direction of the burner 20,
thereby reducing the
distance a spark must travel when the igniter 30 is activated. To facilitate a
spark, it is intended
that the electrode 38 be positioned approximately 3/16" (with a 1/32"
tolerance) from the burner
tube, although the device may still work if the spacing criteria is not met.
Referring now to Figure 1, a perspective view of a first embodiment of a gas
burner
igniter assembly 10 is provided. While the gas burner igniter assembly 10 is
shown attached to a
gas burner 20 of the type which is typically used for gas barbecue grills, it
is contemplated that a
person of ordinary skill in the art could easily configure the igniter
assembly for use with other
types of appliances, such as lamps, furnaces, cooktops, indoor and outdoor
fireplaces or any
other device which requires ignition of a flammable gas.
The particular burner 20 shown in Figure 1 (and 6) is an annular tube which
includes a
first set of orifices (or ports) 22 which are spaced apart along the length of
the burner tube for
distributing flammable gas along the length of the burner tube 20. The burner
tube 20 includes a
second set of orifices 24 near one end of the first set of orifices 22. The
second set of orifices 24
are aligned transverse to the first set 22, whereby the orifices 24 are spaced
apart around a
portion of the circumference of the tube 20. The igniter assembly 10 is
attached to the burner
tube 20 near a first end of the burner tube 20, generally above the first and
second set of orifices
22, 24. Two of the orifices from the first set of orifices 22 are directly
below the hood 32 of the
igniter 30 to provide sufficient combustible gas for ignition. Depending upon
the orientation and
size of the orifices, more or less orifices may be used. The second set of
orifices 24 serve to
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provide a source of combustible gas for manual ignition, if required.
The igniter assembly 10 generally comprises an igniter 30, a bracket 40 and
lead wires
60, 70. The bracket 40 serves to position the igniter 30 in close proximity to
the orifices 22, 24
of the gas burner 20. The first embodiment of the bracket 40, as shown in
Figures 1 and 2, has a
first portion which engages with the igniter 30 and a second portion which
engages with the
burner tube. The first portion of the bracket 40 includes a first set of
opposing wings 44, 46.
Each of the wings 44, 46 includes an aperture 45, 47 which are aligned for
receiving and holding
the igniter 30 therein. The wing 46 is at a slight angle with respect to the
other wing 44 and
holds the igniter 30 is place by a friction fit. Although the wing 46 is
tilted towards the wing 44,
it is contemplated that the wing 44 could also be parallel with or titled away
from the wing 46.
The second portion of the bracket 40 comprises a second pair of wings 42a, 42b
which are
welded to the burner tube. The bracket 40 also includes a ground terminal 48
which is adapted
to engage with a grounded lead wire 70. In the shown embodiment, the ground
terminal 48 is a
male ground terminal. While the ground terminal 48 depends from the wing 42a,
it is
contemplated that the ground terminal 48 could depend from any other portion
of the bracket 40.
A second embodiment of the bracket 140 is shown in Figure 5. The second
embodiment
of the bracket 140, like the first embodiment 40, includes a first portion
which engages with the
burner tube 20, a second portion which engages with the igniter 30, and a
ground terminal 148.
In contrast to the first embodiment of the burner tube, however, the second
portion of the bracket
140 is not permanently attached to the burner tube 20 by welding. Instead, the
first portion of
the bracket 140 includes resilient gripping members or spring members 142a,
142b which grip
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the burner tube 20 and can be attached and removed from the burner tube
without the use of
tools. In that regard, the bracket 140 is suitable for use in retrofit
applications to replace earlier-
generation igniters and gas collector boxes which have deteriorated. The snap-
fit connection
142a, 142b makes it simple for consumers to change out the deteriorated
igniter assemblies. To
install a new igniter 30 on an existing barbecue grill, the consumer simply
snaps the bracket 140
into place on the burner tube 20, inserts the igniter 30 into the first
portion of the bracket 140,
and connects the lead wires 60, 70 to the igniter 30 and the bracket 140.
A third embodiment of a bracket 240 is shown in Figures 6 and 7. The third
embodiment
of the bracket 240 comprises two members 240a, 240b that can be disassembled
to allow the
burner tube and the first member 240a of the bracket 240 to be separately
shipped from the
supplier(s). As compared to the first embodiment, this configuration allows
the burner tubes 20
to be more compactly boxed for shipment and prevents bending of the wings 244,
246 during
shipping. The first member 240a of the bracket 240 engages with the igniter 30
and the second
member 240b engages with the burner tube. The first member 240a includes a
first set of
opposing wings 244, 246, which are identical in nearly all respects to the
wings 44, 46 of the
first embodiment, and a ground terminal 248 which is adapted to engage with a
grounded lead
wire 70. The underside of the second member 240b is welded to the burner tube
20.
The first and second members 240a, 240b are configured for mating engagement.
In the
shown embodiment, the first and second members 240a, 240b are configured for
sliding
engagement. In particular, the second member 240b includes upturned wing
members 242a,
242b which form slots for receiving corresponding wing members 243a, 243b of
the first
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member 240a. The first and second members 240a, 240b include locking members
245a, 245b
which engage to firmly hold the first and second members 240a, 240b together.
In the shown
embodiment, the locking members 245a, 245b provide a snap-fit. The locking
member 245a is
an aperture (as shown) or recessed dimple (not shown) and the locking member
245b is a raised
portion or raised dimple which is received by the locking member 245a. The
first member 240a
includes a stop 247 which abuts the upturned wing member 243b when the first
member 240a is
properly positioned in mating engagement with the second member 240b.
In Figures 8-11, another embodiment of an igniter assembly 310 is shown which
includes
a fourth embodiment of a bracket 340. Figures 8-9 show the igniter assembly
310, along with e
burner 120, in a barbecue grill firebowl 80. Figures 10-11 show close-up
perspective views of
the igniter assembly 310. As a means of improving assembly time and reducing
the labor
required to assemble the barbecue grill, the igniter assembly 310 is
configured to be installed
concurrently with the burner 120 in the firebox 80 of a barbecue grill.
In the shown embodiment, the burner 120 is a tube having a curvilinear, loop
configuration, a series of orifices 122 oriented in an upward direction about
the entire loop, and a
series of three orifices 122a, 122b, 122c. The three orifices 122a, 122b, and
122c are aligned
transverse to orifices 122 about a portion of the circumference of the burner
120. It is
contemplated, that other sizes, types, and configurations of burners 120 can
be used.
The firebowl 80 includes a mounting ledge 82 which extends into a socket 84
for holding
and securing the burner 120 and igniter assembly 310. The mounting ledge 82 is
configured to
receive a common fastener (not shown), such as a nut and bolt, for securing
the burner 120 and
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igniter assembly 310 in place. As shown, the mounting ledge includes an
aperture 86, or through
hole, for receiving the fastener and is provided with a recessed socket 88 on
the underside of the
aperture 86. The socket 88 has a shape which corresponds to a nut (not shown)
whereby the
socket 88 receives and holds the nut to prevent rotation thereof. The nut may
be welded in the
socket 88. Both the burner 120 and the bracket 340 include flange portions
124, 342,
respectively. The flange portions 124, 342 each include apertures or slots
126, 344 that are
configured to align with the aperture 86 in an assembled configuration. In the
shown
embodiment, the burner 120 has a slot to allow the assembler to adjust the
position of the burner
120 relative to the igniter assembly 310.
In the assembled position, the hood portion 32 of the igniter 30 is positioned
generally
above orifices 122a, 122b, 122c, which provide combustion gas to the igniter
assembly 310. The
hood portion 32 of the igniter extends outward from the bracket 340 to
mitigate or prevent the
flames from directly impinging upon the bracket 340. Like the previous
embodiments, the
bracket 340 includes a ground terminal 348. The ground terminal 348 of the
fourth embodiment
340, however, is spring loaded to retain the igniter 30 in place.
The brackets 40, 140, 240, 340 are fabricated from a conductive material, such
as sheet
metal which is stamped and/or formed into shape. As discussed in more detail
above, the
brackets 40, 140, 240, 340 include push-on type ground terminals 48, 148, 248,
348 which are
configured for attachment to a grounded lead wire 70 to ground the bracket.
The connections
between the burner 20, 120 and the bracket 40, 140, 240, 340 serve to pass the
ground from the
bracket to the burner 20, 120 . In this manner, when the igniter 30 is
activated, a spark passes
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between the igniter 30 and the grounded burner 20 thereby igniting the
flammable gas.
Although the inventions described and claimed herein have been described in
considerable detail with reference to certain embodiments, one skilled in the
art will appreciate
that the inventions described and claimed herein can be practiced by other
than those
embodiments, which have been presented for purposes of illustration and not of
limitation.
Therefore, the spirit and scope of the appended claims should not be limited
to the description of
the embodiments contained herein.
Indeed, it is expected that persons of ordinary skill in the art of grill
design may devise a
number of alternative configurations for the brackets and igniter that are
similar and equivalent
to the embodiments shown and described herein. For example, the brackets need
not be formed
from a conductive material. In such a case, the grounded lead wire could be
directly connected
to the burner tube. Also, the bracket need not be attached to the burner tube.
It is contemplated
that the bracket could be attached to other components, whereby the bracket
could be configured
to position the igniter in close proximity to the gas source. Even further,
while the embodiments
above describe the bracket and igniter as separate components, it is
contemplated that the bracket
and the igniter could be integrated into a single component. Even further yet,
while the
embodiments above describe the burner tube as being grounded whereby the
ignition spark
travels between the electrode and the burner, it is contemplated that a ground
wire could also be
embedded in the igniter body. In such a case, a portion of the ground wire (or
an extension
thereof, such as a plate) would be exposed near the wall of the collection
portion of the igniter,
whereby the ignition spark would travel between the wall of the collector
portion and the
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electrode. Even further, while the embodiments of the ceramic igniter describe
the sleeve
portion and collector portion to be integrally cast, it is contemplated that
the igniter need not be
integrally cast. In fact, the sleeve portion and the collector portion need
not be a single
component.
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