U.S. patent application number 14/288970 was filed with the patent office on 2015-12-03 for asymmetrically fed stability chamber for a gas burner.
This patent application is currently assigned to General Electric Company. The applicant listed for this patent is General Electric Company. Invention is credited to Paul Bryan Cadima, John Thurl Pottenger.
Application Number | 20150345799 14/288970 |
Document ID | / |
Family ID | 54701302 |
Filed Date | 2015-12-03 |
United States Patent
Application |
20150345799 |
Kind Code |
A1 |
Cadima; Paul Bryan ; et
al. |
December 3, 2015 |
ASYMMETRICALLY FED STABILITY CHAMBER FOR A GAS BURNER
Abstract
A gas burner assembly for an appliance has a gas stability
chamber with a simmer flame port for providing a re-ignition source
to primary burner ports positioned around the burner. The gas
stability chamber has at least one primary stability chamber gas
inlet and at least one secondary stability chamber gas inlet. The
secondary stability chamber gas inlet is configured to provide a
gas flow in the stability chamber with a velocity component that is
offset from a radial direction of the gas burner assembly. This
offset causes a flame at the simmer flame port to drift in the
direction of an opposing side of the stability chamber from the
secondary stability chamber gas inlet. As a result, the flamelet at
the simmer flame port can more readily ignite the fuel exiting
adjacent primary burner ports.
Inventors: |
Cadima; Paul Bryan;
(Prospect, KY) ; Pottenger; John Thurl; (Mount
Washington, KY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
General Electric Company |
Schenectady |
NY |
US |
|
|
Assignee: |
General Electric Company
Schenectady
NY
|
Family ID: |
54701302 |
Appl. No.: |
14/288970 |
Filed: |
May 28, 2014 |
Current U.S.
Class: |
126/39E |
Current CPC
Class: |
F24C 3/085 20130101;
F24C 3/126 20130101 |
International
Class: |
F24C 3/08 20060101
F24C003/08 |
Claims
1. A gas burner assembly for a cooktop of an appliance, comprising:
a burner body comprising an annular sidewall surrounding a main gas
conduit having a gas inlet and a gas outlet, the burner body
defining circumferential, axial, and radial directions, the burner
body having an upper surface; a plurality of primary burner ports
disposed within the annular sidewall of the burner body,
surrounding the gas outlet, and in fluid communication with the
main gas conduit through the gas outlet; a cap received onto the
burner body; a simmer flame port disposed within the annular
sidewall, spaced along a circumferential direction from the primary
burner ports, and configured to provide a reignition source for the
primary burner ports; a stability chamber located adjacent to, and
radially inward of, the simmer flame port, the stability chamber
defined at least in part by a pair of baffles extending along the
radial direction, positioned in an opposing manner from each other
along the circumferential direction, and projecting from the upper
surface along the axial direction; an end wall positioned radially
inward of the pair of baffles; the upper surface of the burner
body; and the cap; at least one primary stability chamber gas inlet
configured for providing gaseous fuel flow from the gas outlet into
the stability chamber, and a secondary stability chamber gas inlet
positioned along one of the baffles at a location that is radially
outward of the at least one primary stability chamber gas inlet and
configured for providing gaseous fuel flow from the gas outlet into
the stability chamber, the secondary gas inlet oriented to provide
gas flow into the stability chamber with a velocity component that
is offset from the radial direction so as to cause a flame at the
simmer flame port to drift in a direction towards an opposing side
of the stability chamber from the secondary stability chamber gas
inlet.
2. The gas burner assembly of claim 1, wherein the secondary
stability chamber gas inlet comprises a channel formed along one of
the baffles.
3. The gas burner assembly of claim 2, wherein the channel defines
a channel axis that forms an acute, non-zero angle .alpha. to the
radial direction.
4. The gas burner assembly of claim 3, wherein angle .alpha. is in
the range of 0 degrees<.alpha..ltoreq.60 degrees.
5. The gas burner assembly of claim 3, wherein angle .alpha. is in
the range of 0 degrees<.alpha..ltoreq.45 degrees.
6. The gas burner assembly of claim 2, wherein the channel is
located along a top edge of one of the baffles.
7. The gas burner assembly of claim 2, wherein the channel is
located away from the end wall along one of the baffles at a
distance that is more than half the length of the baffle.
8. The gas burner assembly of claim 1, wherein the burner body
defines a toroidal projection around the gas outlet, and wherein
the annular sidewall and the toroidal projection define a main fuel
chamber for the receipt of gas from the gas outlet.
9. The gas burner assembly of claim 1, wherein the at least one
primary stability chamber gas inlet comprises a pair of primary
stability chamber gas inlets positioned in an opposing manner about
the stability chamber.
10. A cooktop appliance comprising the gas burner assembly of claim
1.
11. A gas burner assembly for a cooktop of an appliance,
comprising: a burner body comprising an annular sidewall
surrounding a main gas conduit, the burner body defining
circumferential, axial, and radial directions, the burner body
having an upper surface; a plurality of primary burner ports
disposed within the annular sidewall of the burner body,
surrounding the gas outlet, and in fluid communication with the
main gas conduit; a cap received onto the burner body; a simmer
flame port disposed within the annular sidewall, spaced along a
circumferential direction from the primary burner ports, and
configured to provide a reignition source for the primary burner
ports; a stability chamber located adjacent to, and radially inward
of, the simmer flame port, the stability chamber defined at least
in part by a pair of baffles extending along the radial direction;
an end wall positioned radially inward of the pair of baffles; the
upper surface of the burner body; and the cap; a pair of primary
stability chamber gas inlets configured for providing gaseous fuel
flow from the gas outlet into the stability chamber, and a
secondary stability chamber gas inlet positioned along one of the
baffles at a location that is radially outward of the primary
stability chamber gas inlets and configured for providing gaseous
fuel flow from the gas outlet into the stability chamber, the
secondary gas inlet oriented to provide gas flow into the stability
chamber with a velocity component that is offset from the radial
direction so as to cause a flame at the simmer flame port to drift
towards one of the primary burner ports.
12. The gas burner assembly of claim 11, wherein the secondary
stability chamber gas inlet comprises a channel formed along one of
the baffles.
13. The gas burner assembly of claim 12, wherein the channel
defines a channel axis that forms an acute, non-zero angle .alpha.
to the radial direction.
14. The gas burner assembly of claim 13, wherein angle .alpha. is
in the range of 0 degrees<.alpha..ltoreq.60 degrees.
15. The gas burner assembly of claim 14, wherein angle .alpha. is
in the range of 0 degrees<.alpha..ltoreq.60 degrees.
16. The gas burner assembly of claim 14, wherein angle .alpha. is
in the range of 0 degrees<.alpha..ltoreq.45 degrees.
17. The gas burner assembly of claim 12, wherein the channel is
located along a top edge of one of the baffles.
18. The gas burner assembly of claim 12, wherein the channel is
located away from the end wall along one of the baffles at a
distance that is more than half the length of the baffle.
19. The gas burner assembly of claim 11, wherein the burner body
defines a toroidal projection around the gas outlet, and wherein
the annular sidewall and the toroidal projection define a main fuel
chamber for the receipt of gas from the gas outlet.
Description
FIELD OF THE INVENTION
[0001] The subject matter of the present disclosure relates
generally to a gas burner for the cooktop of an appliance.
BACKGROUND OF THE INVENTION
[0002] Gas burners are commonly used on the cooktops of household
gas cooking appliances including e.g., range ovens and cooktops
built into cabinetry. A significant factor in the performance of
gas burners is their ability to withstand airflow disturbances in
the surroundings, such as room drafts, rapid movement of cabinet
doors, and most commonly rapid oven door manipulation. For
appliances which comprise both an oven and cooktop, manipulation of
the oven door can be particularly troublesome because rapid
openings and closings of the oven door can produce respective
under-pressure and over-pressure conditions within the oven cavity.
These pressure changes may cause rapid expansion and/or
contractions in the structures. As a result, a large amount of air
passes through or around the gas burners with e.g., rapid opening
or closing of the oven doors. Similarly for built in cooktops,
pressure changes due to rapid manipulation of surrounding cabinets
may result in large amounts of airflow through or around the gas
burners.
[0003] Such surges of air around the gas burners, due to pressure
disturbances in the surroundings, are detrimental to the flame
stability of the burners and may cause extinction of the flames.
This flame stability problem is particularly evident in sealed gas
burner arrangements, which lack an opening in the cooktop surface
around the base of the burner so as to prevent spills from entering
the area beneath the cooktop.
[0004] The inherent cause of this flame instability is the low
pressure drop of the fuel/air mixture passing through the burner
ports of a typical burner used on the cooktop of an appliance.
Although there is ample pressure available in the fuel, the
pressure energy is used to accelerate the fuel to the high
injection velocity required for primary air entrainment. Relatively
little of this pressure is available at the burner ports. A low
pressure drop across the ports allows pressure disturbances
propagating through the ambient to easily pass through the ports,
momentarily drawing the flame towards the burner head and leading
to thermal quenching and extinction.
[0005] An additional problem is that rapid adjustments of the fuel
supply to a gas burner from a high burner input rate to a low
burner input rate often will cause flame extinction when the
momentum of the entrained air flow continues into the burner even
though fuel has been cut back, resulting in a momentary drop in the
fuel/air ratio, and causing extinction.
[0006] A solution to the above-described problem is the use of a
stability chamber as described e.g., in U.S. Pat. No. 5,800,159,
commonly owned by the assignee of the present invention. In one
embodiment, the stability chamber is formed from baffles extending
radially outward from a burner throat and in a widening manner
towards a simmer flame port. Primary burner ports are positioned
proximate the simmer flame port. Fuel inlets to the stability
chamber are positioned proximate the burner throat. The burner is
able to maintain the simmer flame at both low and high settings so
that the simmer flame can relight the flame at the primary burner
ports when needed.
[0007] One challenge with stability chambers is the inherently slow
velocity of the fuel mixture exiting the chamber. The slow velocity
is necessary to make a stability chamber robust to disturbances but
also reduces the flame's kinetic energy and associated ability to
entrain secondary air. Drafts, whether induced by the local gas
flow of the burner itself or by external influences, can push or
pull the resulting lazy plume exiting the stability chamber into a
flame from an adjacent burner port. When this occurs, the two
flames tend to coalesce and become starved for air locally at the
relatively higher flow rate of the coalesced plume. This in turn
causes this plume of flame to further extend upwardly for more air
and impinge on cool surrounding surfaces such as the cookware above
the burner. The cool surfaces quench the flame, preventing complete
combustion, and causing carbon or soot formation. Increasing the
distance between the chamber and adjacent ports is often done to
reduce this tendency to coalesce. Yet in doing so, the ability of
the chamber to ignite the adjacent ports at low flow rates becomes
increasingly unlikely.
[0008] Accordingly, an improved gas burner for an appliance would
be useful. More particularly, a gas burner having an improved
ability to relight while preventing or minimizing soot formation
associated with a stability chamber would be beneficial.
BRIEF DESCRIPTION OF THE INVENTION
[0009] The present invention provides a gas burner assembly for an
appliance that has a gas stability chamber with a simmer flame port
for providing a reignition source to primary burner ports
positioned around the burner. The gas stability chamber has at
least one primary stability chamber gas inlet and at least one
secondary stability chamber gas inlet. The secondary stability
chamber gas inlet is configured to provide a gas flow in the
stability chamber with a velocity component that is offset from a
radial direction of the gas burner assembly. This offset causes, at
lower firing rates, a flame at the simmer flame port to drift in
the direction of an opposing side of the stability chamber from the
secondary stability chamber gas inlet. As a result, the flamelet at
the simmer flame port can more readily ignite the fuel exiting
adjacent primary burner ports. This offset component becomes less
and less influential at higher firing rates where coalescence and
soot formation is more likely. Additional aspects and advantages of
the invention will be set forth in part in the following
description, or may be apparent from the description, or may be
learned through practice of the invention.
[0010] In one exemplary embodiment, the present invention provides
a gas burner assembly for a cooktop of an appliance that includes a
burner body having an annular sidewall surrounding a main gas
conduit having a gas inlet and a gas outlet. The burner body
defines circumferential, axial, and radial directions; and the
burner body has an upper surface. A plurality of primary burner
ports are disposed within the annular sidewall of the burner body,
surround the gas outlet, and are in fluid communication with the
main gas conduit through the gas outlet. A cap is received onto the
burner body. A simmer flame port is disposed within the annular
sidewall, spaced along a circumferential direction from the primary
burner ports, and is configured to provide a reignition source for
the primary burner ports. A stability chamber is located adjacent
to, and radially inward of, the simmer flame port. The stability
chamber is defined at least in part by a pair of baffles extending
along the radial direction, positioned in an opposing manner from
each other along the circumferential direction, and projecting from
the upper surface along the axial direction. The stability chamber
is also defined by an end wall positioned radially inward of the
pair of baffles, the upper surface of the burner body, and the cap.
At least one primary stability chamber gas inlet is configured for
providing gaseous fuel flow from the gas outlet into the stability
chamber. A secondary stability chamber gas inlet is positioned
along one of the baffles at a location that is radially outward of
the at least one primary stability chamber gas inlet and is
configured for providing gaseous fuel flow from the gas outlet into
the stability chamber. The secondary gas inlet oriented to provide
gas flow into the stability chamber with a velocity component that
is offset from the radial direction so as to cause a flame at the
simmer flame port to drift in a direction towards an opposing side
of the stability chamber from the secondary stability chamber gas
inlet.
[0011] In another exemplary embodiment, the present invention
provides a gas burner assembly for a cooktop of an appliance. The
gas burner assembly includes a burner body having an annular
sidewall surrounding a main gas conduit. The burner body defines
circumferential, axial, and radial directions. The burner body has
an upper surface. A plurality of primary burner ports are disposed
within the annular sidewall of the burner body, surround the gas
outlet, and are in fluid communication with the main gas conduit. A
cap is received onto the burner body. A simmer flame port is
disposed within the annular sidewall, spaced along a
circumferential direction from the primary burner ports, and is
configured to provide a reignition source for the primary burner
ports. A stability chamber is located adjacent to, and radially
inward of, the simmer flame port. The stability chamber defined at
least in part by i) a pair of baffles extending along the radial
direction; ii) an end wall positioned radially inward of the pair
of baffles; iii) the upper surface of the burner body; and iv) the
cap. A pair of primary stability chamber gas inlets are configured
for providing gaseous fuel flow from the gas outlet into the
stability chamber. A secondary stability chamber gas inlet is
positioned along one of the baffles at a location that is radially
outward of the primary stability chamber gas inlets and is
configured for providing gaseous fuel flow from the gas outlet into
the stability chamber. The secondary gas inlet is oriented to
provide gas flow into the stability chamber with a velocity
component that is offset from the radial direction so as to cause a
flame at the simmer flame port to drift towards one of the primary
burner ports.
[0012] These and other features, aspects and advantages of the
present invention will become better understood with reference to
the following description and appended claims. The accompanying
drawings, which are incorporated in and constitute a part of this
specification, illustrate embodiments of the invention and,
together with the description, serve to explain the principles of
the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] A full and enabling disclosure of the present invention,
including the best mode thereof, directed to one of ordinary skill
in the art, is set forth in the specification, which makes
reference to the appended figures, in which:
[0014] FIG. 1 is a perspective view of an exemplary embodiment of a
cooktop appliance of the present invention.
[0015] FIG. 2 is an exploded, perspective view of an exemplary
embodiment of a burner assembly of the present invention.
[0016] FIG. 3 is a top view of the exemplary embodiment of FIG.
2.
[0017] FIG. 4 is a top view of a portion of the exemplary burner
assembly of FIG. 2.
[0018] FIG. 5 is another top view of the exemplary embodiment of
FIG. 2 with a schematic depiction of certain flames as more fully
described below.
[0019] FIG. 6 is a top view of a burner assembly without a
secondary stability chamber gas inlet.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Reference now will be made in detail to embodiments of the
invention, one or more examples of which are illustrated in the
drawings. Each example is provided by way of explanation of the
invention, not limitation of the invention. In fact, it will be
apparent to those skilled in the art that various modifications and
variations can be made in the present invention without departing
from the scope or spirit of the invention. For instance, features
illustrated or described as part of one embodiment can be used with
another embodiment to yield a still further embodiment. Thus, it is
intended that the present invention covers such modifications and
variations as come within the scope of the appended claims and
their equivalents.
[0021] FIG. 1 illustrates an exemplary embodiment of a cooktop
appliance 100 as may be employed with the present subject matter.
Cooktop appliance 100 includes a top panel 104. By way of example,
top panel 104 may be constructed of glass, ceramics, enameled
steel, and combinations thereof. Top panel 104 may be part of a
range or other appliance, or panel 104 may be a stand-alone
appliance.
[0022] For cooktop appliance 100, a utensil holding food and/or
cooking liquids (e.g., oil, water, etc.) may be placed onto grates
116 at a location of any of a plurality of burner assemblies 110.
As shown in FIG. 1, burner assemblies 110 can be configured in
various sizes so as to provide e.g., for the receipt of cooking
utensils (i.e., pots, pans, etc.) of various sizes and
configurations and to provide different heat inputs for such
cooking utensils. Grates 116 are supported on a top surface 118 of
top panel 104.
[0023] Burner assemblies 110 provide thermal energy to cooking
utensils on grates 116. In particular, burner assemblies 110 extend
through top panel 104 below grates 116. Burner assemblies 110 are
also mounted to top panel 104. Burner assemblies 110 provide for
combustion of a gaseous fuel to provide heat energy for
cooking.
[0024] A user interface panel 112 is located within convenient
reach of a user of the cooktop appliance 100. For this exemplary
embodiment, panel 112 includes knobs 114 that are each associated
with one of burner assemblies 110. Knobs 114 allow the user to
activate each burner assembly 110 and determine the amount of heat
input provided by each burner assembly 110 to a cooking utensil
located thereon. Panel 112 may also be provided with one or more
graphical display devices that deliver certain information to the
user such as e.g., whether a particular burner assembly is
activated and/or the level at which the burner assembly is set.
[0025] Although shown with knobs 114, it should be understood that
knobs 114 and the configuration of cooktop appliance 100 shown in
FIG. 1 are provided by way of example only. More specifically, user
interface 112 may include various input components, such as one or
more of a variety of touch-type controls, electrical, mechanical,
or electro-mechanical input devices including rotary dials, push
buttons, and touch pads. The user interface 112 may include other
display components, such as a digital or analog display device
designed to provide operational feedback to a user.
[0026] Cooktop appliance 100 shown in FIG. 1 illustrates an
exemplary embodiment of the present subject matter. Thus, although
described in the context of cooktop appliance 100, the present
subject matter may be used in cooktop appliances having other
configurations, e.g., a cooktop appliance with one, two, or more
additional burner assemblies. Similarly, the present subject matter
may be used in cooktop appliances that are part of an oven such as
e.g., range appliances.
[0027] FIG. 2 illustrates an exploded view of an exemplary
embodiment of a burner assembly 110 of the present invention while
FIG. 3 provides a top view (with a cap 98 removed) of the same.
Burner assembly 110 includes a burner body 120 that supports
removable cap 98. Burner body 120 may be constructed as an integral
piece that includes various features as described herein. For
reference purposes, burner body 120 defines an axial direction A,
radial direction R, and circumferential direction C.
[0028] A flow G of gaseous fuel enters burner body 120 through gas
inlet 122 and travels along main gas conduit 96 to a gas outlet 124
where it will impinge upon cap 98. The gaseous fuel will then flow
radially outward through a main fuel chamber 132 formed between cap
98 and upper surface 154 of burner body 120. The gaseous fuel will
flow towards an annular sidewall 126 defined by burner body 120. In
turn, annular sidewall 126 defines a plurality of primary burner
ports 128, which are openings through which the gaseous fuel may
travel to the exterior of burner assembly 110.
[0029] As shown, primary burner ports 128 are spaced apart from
each other along circumferential direction C and surround gas
outlet 124. Through gas outlet 124, each primary burner port 128 is
in fluid communication with gaseous fuel flow G through main gas
conduit 96. Primary burner ports 128 supply the main source of
gaseous fuel that, after mixing with the surrounding air, is
combusted to provide heat energy for cooking operations.
[0030] Gas burner assembly 110 also includes a simmer flame port
130 disposed within annular sidewall 126 and spaced along
circumferential direction C from the primary burner ports 128.
During cooking operations, particularly at low settings where the
flow of gaseous fuel is low, simmer flame port 130 provides a
reignition source for primary burner ports 128.
[0031] Gaseous fuel is fed to simmer flame port 130 from a
stability chamber 134. As shown, stability chamber 134 is located
adjacent to, and radially inward of, simmer flame port 130.
Stability chamber 134 is defined in part by a pair of baffles 138,
140 that extend along radial direction R. Baffles 138 and 140 are
spaced apart, positioned in an opposing manner along
circumferential direction C, and project from upper surface 154
along axial direction A. For this exemplary embodiment, stability
chamber 134 is also defined in part by upper surface 154, cap 98,
and an end wall 136 positioned radially inward of baffles 138 and
140 on a toroidal projection 152.
[0032] Gaseous fuel from gas outlet 124 is fed to stability chamber
134 by a pair of primary stability chamber gas inlets 142 and 144,
which are formed as gaps or openings between end wall 136 and
radially inward ends 160 and 162 of baffles 138 and 140. For this
exemplary embodiment, the two gas inlets 142 and 144 create an
overall flow of gaseous fuel through stability chamber 134 that is
primarily along radial direction R. In other embodiments of the
invention, a different number of openings may be used for the
primary stability chamber gas inlets and may be positioned at
different locations relative to, or along, baffles 138 and 140.
[0033] Gaseous fuel is also fed to stability chamber 134 by a
secondary stability chamber gas inlet 146 that is positioned along
baffle 140. As shown, secondary stability chamber gas inlet 146 is
located only along one side of stability chamber 134 and at a
location that is radially outward of the primary stability chamber
gas inlets 142 and 144. Gaseous fuel is fed to secondary stability
chamber gas inlet 146 from gas outlet 124.
[0034] Secondary stability chamber gas inlet 146 is configured so
as to provide gas flow in stability chamber 134 having a velocity
component that is offset from radial direction R. Referring to FIG.
4, for this embodiment, gas inlet 146 is positioned on a top edge
164 of baffle 140 and is formed as a channel between surfaces 156
and 158 as provided by top portions 140a and 140b of baffle 140.
Cap 98 and top edge 164 located between surfaces 156 and 158 also
form channel 146.
[0035] Channel axis CA is parallel with surfaces 156 and 158 and is
oriented so as to form an acute, non-zero angle .alpha. with the
radial direction R or with the radially inward portion 140a of
baffle 140. In one exemplary embodiment, angle .alpha. is in the
range of 0 degrees<.alpha..ltoreq.60 degrees. In another
exemplary embodiment, angle .alpha. is in the range of 0
degrees<.alpha..ltoreq.45 degrees.
[0036] Additionally, baffle 140 has a length L along radial
direction R. Secondary stability chamber gas inlet 146 is located a
position P along baffle 140 as measured along the top edge 164 of
baffle 140. For this exemplary embodiment, the ratio P/L is about
2/3 or more. However, other ratios for P/L may be used. Inlet 146
has a width W along radial direction R as shown.
[0037] The values for angle .alpha., width W, and ratio P/L are all
chosen so that secondary stability chamber gas inlet 146 imparts a
velocity component to the gas flow through inlet 146 that is offset
from the radial direction during low gas flow but has minimal
effect when the burner is operating at high gas flow. FIG. 5
illustrates another top view of the exemplary burner assembly 110
with cap 98 removed from burner body 120 for purposes of
explanation. As indicated by arrows F, gaseous fuel flows in
stability chamber 134 through inlets 142 and 144. This results in
an overall primary flow R.sub.1 and R.sub.2 along radial direction
R.
[0038] As shown, a smaller amount of secondary gaseous fuel flow L
enters stability chamber 134 through secondary stability chamber
gas inlet 146. During periods of low gas flow from gas outlet 124,
this secondary flow L causes a simmer flame S at simmer flame port
130 to drift in a direction that is towards an opposing side of the
stability chamber 134 from the secondary stability chamber gas
inlet 146--i.e. in a direction from baffle 140 towards baffle 138.
As a result, simmer flame S at simmer flame port 130 is caused to
drift towards a primary burner port 128b that is adjacent to simmer
flame port 130. If flames at ports 128 have otherwise been
extinguished due to e.g., drafts as previously described, simmer
flame S will ignite a flame P.sub.1 at port 128b that will spread
to ignite flame P.sub.2 at another port 128 and continue so along
circumferential direction C until a flame is positioned at each
primary burner port 128--including primary burner port 128c.
[0039] In contrast, FIG. 6 illustrates a burner body 20 without
secondary stability chamber gas inlet 146. As indicated by arrows
F, gas flows into stability chamber 34 from gas outlet 22. A flow
of gas B is created along radial direction R that creates a simmer
flame S at simmer flame port 30. During periods of low flow when
the flame at ports 28 may be extinguished, simmer flame S will
eventually reignite flame P.sub.1, P.sub.3, or both. The flame will
spread along circumferential direction C to reignite the burner at
all ports 28 including e.g., P.sub.2 and P.sub.4. However, without
the tangential velocity component provided by secondary stability
chamber gas inlet 146, simmer flame S must be larger in size in
order to quickly ignite adjacent ports 128. Consequently, at higher
firing rates simmer flame S is larger and thus more likely to
coalesce with flame P1 or P3 causing a non-uniform flame appearance
and potentially soot formation. The present invention can
advantageously avoid this problem while providing for reignition of
the flame when drafts or other events cause burner 110 to be
extinguished.
[0040] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to practice the invention, including making and
using any devices or systems and performing any incorporated
methods. The patentable scope of the invention is defined by the
claims, and may include other examples that occur to those skilled
in the art. Such other examples are intended to be within the scope
of the claims if they include structural elements that do not
differ from the literal language of the claims, or if they include
equivalent structural elements with insubstantial differences from
the literal languages of the claims.
* * * * *