U.S. patent application number 13/099465 was filed with the patent office on 2011-11-03 for cooking range burner arrangement.
Invention is credited to RANDALL B. DIGGINS.
Application Number | 20110265782 13/099465 |
Document ID | / |
Family ID | 44148613 |
Filed Date | 2011-11-03 |
United States Patent
Application |
20110265782 |
Kind Code |
A1 |
DIGGINS; RANDALL B. |
November 3, 2011 |
COOKING RANGE BURNER ARRANGEMENT
Abstract
A cooking range burner head arrangement includes an annular
burner head with a plurality of gas orifices, the burner head
including a centrally disposed opening defining a first flow path
for flowing secondary air upward into a combustion space proximate
the burner head. A secondary air flow metering arrangement is
associated with the burner head, the secondary air flow metering
arrangement defining a second flow path and a third flow path, the
second flow path located for flowing secondary air to the
combustion space above the secondary flow provided by the first
flow path, the third flow path located for flowing secondary air to
the combustion space above the secondary flow provided by the
second flow path.
Inventors: |
DIGGINS; RANDALL B.;
(Baltimore, MD) |
Family ID: |
44148613 |
Appl. No.: |
13/099465 |
Filed: |
May 3, 2011 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61330668 |
May 3, 2010 |
|
|
|
Current U.S.
Class: |
126/39E |
Current CPC
Class: |
F23L 9/00 20130101; F23D
2900/14062 20130101; F23D 14/085 20130101; F23D 14/065
20130101 |
Class at
Publication: |
126/39.E |
International
Class: |
F24C 3/00 20060101
F24C003/00 |
Claims
1. A cooking range burner arrangement, comprising: an annular
burner head with a plurality of gas orifices, the burner head
including a centrally disposed opening defining a first flow path
for flowing secondary air upward into a combustion space proximate
the burner head; a bowl arrangement associated with the burner
head, the bowl arrangement defining a second flow path and a third
flow path, the second flow path located for flowing secondary air
to the combustion space above the secondary flow provided by the
first flow path, the third flow path located for flowing secondary
air into the combustion space above the secondary flow provided by
the second flow path.
2. The cooking range burner arrangement of claim 1, wherein the
second flow path is radially outward of the first flow path, the
third flow path is radially outward of the second flow path.
3. The cooking range burner arrangement of claim 2 wherein the
second flow path feeds secondary air to a cone and/or mantle flame
region and the third flow path feeds secondary air to a tail flame
region.
4. The cooking range burner arrangement of claim 2, wherein: the
bowl arrangement comprises: an inner bowl structure disposed to
define the first air flow path between an upper portion of the
burner head and a lower portion of the inner bowl structure; an
outer bowl structure disposed at least partially about the inner
bowl structure to define the second air flow path at least
partially between the inner bowl structure and the outer bowl
structure.
5. The cooking range burner arrangement of claim 4, wherein: the
inner bowl structure has a bottom edge aligned with and positioned
above a top surface of the burner head, a wall of the inner bowl
structure extends upwardly and radially outwardly; the outer bowl
structure has a bottom edge positioned higher than the bottom edge
of the inner bowl structure and lower than a top edge of the inner
bowl structure, a wall of the outer bowl structure extends upwardly
and outwardly, and a top edge of the outer bowl structure is
positioned higher than the top edge of the inner bowl
structure.
6. The cooking range burner arrangement of claim 5, wherein the
first bowl structure and second bowl structure act as heat
reflectors to reduce radially outward heat loss.
7. The cooking range burner arrangement of claim 4, further
comprising: a plate positioned above the second bowl structure for
being heated by combustion in the combustion space, the plate
including a plurality of heat exchange fin structures extending
downward toward the combustion space.
8. The cooking range burner arrangement of claim 7 wherein a
multiplicity of the heat exchange fin structures are arranged to
extend radially relative to a central vertical axis of the burner
head.
9. The cooking range burner arrangement of claim 8 wherein radially
inward edges of the multiplicity of heat exchange fin structures
are spaced outward of the central vertical axis, a center region of
the bottom side of the plate lacking any heat exchange fin
structure.
10. The cooking range burner arrangement of claim 9 wherein the
multiplicity of heat exchange fin structures includes a first set
of heat exchange fin structures with radially inward edges
terminating a first distance from the central vertical axis and a
second set of heat exchange fin structures with radially inward
edges terminating a second distance from the central vertical axis,
the second distance greater than the first distance.
11. The cooking range burner arrangement of claim 10 wherein a
radial length of each heat exchange fin structure of the second set
of heat exchange fin structures is substantially less than a radial
length of each heat exchange fin of the first set of heat exchange
fin structures.
12. The cooking range burner arrangement of claim 7 wherein: the
inner bowl structure has a bottom edge aligned with and positioned
above a top surface of the burner head, a wall of the inner bowl
structure extends upwardly and radially outwardly; the outer bowl
structure has a bottom edge positioned higher than the bottom edge
of the inner bowl structure and lower than a top edge of the inner
bowl structure, a wall of the outer bowl structure extends upwardly
and outwardly, and a top edge of the outer bowl structure is
positioned higher than the top edge of the inner bowl structure,
the top edge of the outer bowl structure positioned adjacent lower
edges of the heat exchange fin structures.
13. A cooking range burner arrangement, comprising: an annular
burner head with a plurality of gas orifices, the burner head
including a centrally disposed opening defining a first flow path
for flowing secondary air upward into a combustion space proximate
the burner head; a secondary air flow metering arrangement
associated with the burner head, the secondary air flow metering
arrangement defining a second flow path and a third flow path, the
second flow path located for flowing secondary air to the
combustion space above the secondary flow provided by the first
flow path, the third flow path located for flowing secondary air to
the combustion space above the secondary flow provided by the
second flow path.
14. The cooking range burner arrangement of claim 13, wherein the
second flow path is radially outward of the first flow path, the
third flow path is radially outward of the second flow path.
15. The cooking range burner arrangement of claim 14 wherein the
second flow path feeds secondary air to a cone and/or mantle flame
region and the third flow path feeds secondary air to a tail flame
region.
16. The cooking range burner arrangement of claim 15, wherein: the
secondary air flow metering arrangement comprises: an inner bowl
structure disposed to define the first air flow path between an
upper portion of the burner head and a lower portion of the inner
bowl structure; an outer bowl structure disposed at least partially
about the inner bowl structure to define the second air flow path
at least partially between the inner bowl structure and the outer
bowl structure.
17. A kit for updating an open-top gas burner including a burner
head, the kit comprising: an inner bowl structure for positioning
above the burner head; an outer bowl structure disposed at least
partially about the inner bowl structure to define an air flow path
at least partially between the inner bowl structure and the outer
bowl structure; and a plate member for positioning above the inner
and outer bowl structure.
18. The kit of claim 17 further comprising a support unit for
supporting the plate member and the bowls above the burner
head.
19. The kit of claim 17 wherein the plate member includes a
plurality of radially extending heat exchange fins on its lower
surface.
Description
CROSS-REFERENCES
[0001] The present application claims the benefit of U.S.
provisional application No. 61/330,668, filed May 3, 2010, the
entirety of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to gas fired cooking ranges
and, more particularly, to burner assemblies used in such
ranges.
BACKGROUND
[0003] Gas fired cooking ranges have achieved wide acceptance in
both residential and commercial kitchens. A known design for gas
fired cook tops in ranges includes separate burner assemblies for
each cooking location, with each burner assembly including a
venturi and a burner head having gas-emitting orifices.
[0004] Factors such as flame intensity and efficiency, burner
assembly cleanability and fuel consumption efficiency are important
to both residential and commercial installations. The time required
for completing a food course, including initial preparation time
for heating and actual cooking time, can be reduced by efficient
burner performance and heat transfer to the cooking vessel atop the
burner.
[0005] What is needed in the art are burner assemblies that are
reliable, use fuel efficiently and heat vessels.
SUMMARY
[0006] In one aspect, a cooking range burner arrangement includes
an annular burner head with a plurality of gas orifices. The burner
head includes a centrally disposed opening defining a first flow
path for flowing secondary air upward into a combustion space
proximate the burner head. A bowl arrangement associated with the
burner head defines a second flow path and a third flow path. The
second flow path is located for flowing secondary air to the
combustion space above the secondary flow provided by the first
flow path. The third flow path is located for flowing secondary air
into the combustion space above the secondary flow provided by the
second flow path.
[0007] In the foregoing aspect, the second flow path may be
radially outward of the first flow path, and the third flow path
radially outward of the second flow path.
[0008] In either foregoing aspect, the second flow path may feed
secondary air to a cone and/or mantle flame region and the third
flow path may feed secondary air to a tail flame region.
[0009] In any of the foregoing aspects, the bowl arrangement may
include an inner bowl structure disposed to define the first air
flow path between an upper portion of the burner head and a lower
portion of the inner bowl structure, and an outer bowl structure
disposed at least partially about the inner bowl structure to
define the second air flow path at least partially between the
inner bowl structure and the outer bowl structure.
[0010] In any of the foregoing aspects, a inner bowl structure may
have a bottom edge aligned with and positioned above a top surface
of the burner head, a wall of the inner bowl structure extending
upwardly and radially outwardly, and an outer bowl structure may
have a bottom edge positioned higher than the bottom edge of the
inner bowl structure and lower than a top edge of the inner bowl
structure, a wall of the outer bowl structure extending upwardly
and outwardly, and a top edge of the outer bowl structure
positioned higher than the top edge of the inner bowl
structure.
[0011] In any of the foregoing aspects, a first bowl structure and
second bowl structure may act as heat reflectors to reduce radially
outward heat loss.
[0012] In any of the foregoing aspects, a plate may be positioned
above a second bowl structure for being heated by combustion in the
combustion space, the plate including a plurality of heat exchange
fin structures extending downward toward the combustion space.
[0013] In the immediately foregoing aspect, a multiplicity of the
heat exchange fin structures may be arranged to extend radially
relative to a central vertical axis of the burner head.
[0014] In the immediately foregoing aspect, radially inward edges
of the multiplicity of heat exchange fin structures may be spaced
outward of the central vertical axis, a center region of the bottom
side of the plate lacking any heat exchange fin structure.
[0015] In the immediately foregoing aspect, the multiplicity of
heat exchange fin structures may include a first set of heat
exchange fin structures with radially inward edges terminating a
first distance from the central vertical axis and a second set of
heat exchange fin structures with radially inward edges terminating
a second distance from the central vertical axis, the second
distance greater than the first distance.
[0016] In the immediately foregoing aspect, a radial length of each
heat exchange fin structure of the second set of heat exchange fin
structures may be substantially less than a radial length of each
heat exchange fin of the first set of heat exchange fin
structures.
[0017] In any of the foregoing aspects, an inner bowl structure may
have a bottom edge aligned with and positioned above a top surface
of the burner head, a wall of the inner bowl structure extending
upwardly and radially outwardly; an outer bowl structure may have a
bottom edge positioned higher than the bottom edge of the inner
bowl structure and lower than a top edge of the inner bowl
structure, a wall of the outer bowl structure extending upwardly
and outwardly; and a top edge of the outer bowl structure may be
positioned higher than the top edge of the inner bowl structure,
the top edge of the outer bowl structure positioned adjacent lower
edges of heat exchange fin structures.
[0018] In another aspect, a cooking range burner arrangement
includes an annular burner head with a plurality of gas orifices,
the burner head including a centrally disposed opening defining a
first flow path for flowing secondary air upward into a combustion
space proximate the burner head. A secondary air flow metering
arrangement is associated with the burner head, the secondary air
flow metering arrangement defining a second flow path and a third
flow path, the second flow path located for flowing secondary air
to the combustion space above the secondary flow provided by the
first flow path, the third flow path located for flowing secondary
air to the combustion space above the secondary flow provided by
the second flow path.
[0019] In yet another aspect, a kit for modifying an open-top gas
burner including a burner head includes an inner bowl structure for
positioning above the burner head, an outer bowl structure disposed
at least partially about the inner bowl structure to define an air
flow path at least partially between the inner bowl structure and
the outer bowl structure; and a plate member for positioning above
the inner and outer bowl structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a perspective view of one embodiment of a gas
cooking range;
[0021] FIG. 2 is a perspective view of one embodiment of a dual
burner head unit;
[0022] FIG. 3 is a perspective view of a plate for a burner
arrangement;
[0023] FIG. 4 is a bottom view of the plate of FIG. 3;
[0024] FIG. 5 is a perspective view of an outer bowl structure;
[0025] FIG. 6 is a perspective view of an inner bowl structure;
[0026] FIG. 7 is a cross-section showing the plate of FIG. 3 and
bowls of FIGS. 5 and 6 in relation to a burner head;
[0027] FIG. 8 is a perspective view of another plate;
[0028] FIG. 9 is a bottom view of the plate of FIG. 8;
[0029] FIG. 10 is a perspective view of a support unit; and
[0030] FIG. 11 is a cross-section showing the plate of FIG. 8,
bowls of FIGS. 5 and 6 and support unit of FIG. 10 in relation to a
burner head.
DETAILED DESCRIPTION
[0031] Referring to FIG. 1, numeral 10 designates a gas cooking
range having a cooktop 14 with multiple cooking locations 11 (e.g.,
six in the illustrated embodiment, 3 front and 3 back) with
associated burner heads. In one embodiment, pairs of burner heads
are formed by burner head assemblies 12 (per FIG. 2), but each
burner head could be formed and fed with gas on an individual
basis. Range 10 further includes an oven 16. The range may be a
commercial range or a residential range, taking on a variety of
outward configurations, of which FIG. 1 is merely exemplary.
[0032] Range 10 includes a gas circuit for supplying combustible
gas to each burner head and to an oven burner assembly (not shown).
The gas circuit includes a plurality of flow control valves 18
provided for initiating, terminating and controlling the rate of
gas flow to cooking locations 11 on cook top 14. Range 10 is
supported on casters 20, by which range 10 can be moved a short
distance to clean the area around the range. However, embodiments
without casters are contemplated.
[0033] Exemplary burner head assembly 12 includes a first burner
head 22 and a second burner head 24 at which combustion of gaseous
fuel occurs. A single piece, monolithic casting 30 forms a first
venturi 32 associated with a first burner head base 34 and a second
venturi 36 associated with a second burner head base 38. First
venturi 32 and second venturi 36 provide a flow of gas and primary
combustion air for combustion at first and second burner heads 22,
24, respectively, in front and back locations, respectively, on
cook top 14. First and second gas receivers 40, 42 are provided on
first venturi 32 and second venturi 36, respectively. Each receiver
40, 42 is aligned with a different control valve 18 to receive gas
therefrom when the control valve 18 is opened to allow gas to flow
therethrough. Receivers 40, 42 also admit a flow of ambient air to
mix with the combustible gas in first venturi 32 and second venturi
36 to provide a combustible mixture to burner heads 22, 24.
[0034] FIG. 2 illustrates burner head assembly 12 in a partial
state of disassembly. Each burner head base 34, 38 may be a
substantially annular body defining an open top annular channel 44
between an inner wall 46 and an outer wall 48. Annular channel 44
of burner head base 34 is visible in FIG. 2. A burner head cover 50
is provided on each burner head base 34, 38, with cover 50 on
burner head base 38 being shown in FIG. 2. Each cover 50 has a
plurality of gas-emitting orifices 52 therein through which a
mixture of combustible gas and primary combustion air is
emitted.
[0035] Burner head cover 50 fits on burner head base 38 and is a
multi-surfaced, generally annular structure. Burner head 50
includes a primarily upwardly facing surface 54, which is a top
surface of cover 50. Surfaces radially outward of upwardly facing
surface 54 are generally outwardly facing, and include an upwardly
and outwardly facing surface 56 adjacent upwardly facing surface 54
and a mostly outwardly facing surface 58, which is the outermost
surface of cover 50. Radially inwardly from top surface 54 in cover
50 are multiple surfaces that are generally inwardly facing. An
innermost, mostly inwardly facing surface 60 is provided adjacent
an inward edge 62 of cover 50. An intermediate surface 64 adjoins
innermost surface 60 with top surface 54. Intermediate surface 64
is inwardly and upwardly facing. The number and arrangement of the
cover surfaces could vary. Orifices 52 are shown in various of the
cover surfaces, with the illustrated orifices being exemplary only.
The exact location, size and number or orifices may vary, including
providing orifices in surfaces 56 or 58 if desired. The central
region of each burner head is open, with a restrictor plate 70
positioned therein for metering secondary air flow to the
combustion space via central opening 72 of the plate and an outer
gap 74 formed between the plate and the burner head. The restrictor
plate may also hold an igniter (e.g., via a slot 76).
[0036] Referring now to FIGS. 3-7, one embodiment of a burner head
arrangement is described. FIGS. 3 and 4 show perspective and bottom
plan views respectively of a plate structure 100 having a top
surface 102 and a bottom surface 104. The bottom surface includes a
plurality of heat exchange fins 106 extending downwardly therefrom.
The fins extend radially relative to a center 108 of the plate and
terminate at positions away from the center, such that a center
region of the bottom side of the plate lacks any heat exchange fin
structure. The heat exchange fins include a set of heat exchange
fins 106A with radially inward edges terminating a radial distance
R1 from the center of the plate and a set of heat exchange fins
106B with radially inward edges terminating a large radial distance
R2 from the center of the plate. The fins 106A and 106B are
arranged in an alternating manner about the plate center. In the
illustrated embodiment, a radial length of each heat exchange fin
106B is substantially less than a radial length of each heat
exchange fin 106A (e.g., fins 106B have a radial length that is 60%
or less the radial length of fins 106A). However, variations are
possible. Certain of fins 106A extend further outward of the plate
and include downwardly extend portions to define feet 110 that can
support the plate. The plate may be made of stainless steel, hot
rolled steel, cast iron or other materials. In some embodiments all
or portions (e.g., the bottom surface and/or fins) of the plate may
be coated to further improve heat transfer to the plate structure
(e.g., coated with copper via a plasma spray process). Laminate
plate structures could also be used.
[0037] FIGS. 5 and 6 depict components of a secondary air metering
arrangement. In the illustrated embodiment an inner bow structure
120 and outer bowl structure 122 are provided. The term "bowl" is
used in connection with the structures as they each have a
respective top edge 124, 126 that is spaced outward of the bottom
edge 128, 130 in the manner of a typical bowl. However, the bowl
structures are open at the bottom for purpose of their use in the
secondary air flow metering as will be described below.
[0038] Referring now to FIG. 7, a burner head arrangement
cross-section is provided. The range housing 140 supports a range
aeration pan unit 142. A burner head 24 with associated restrictor
plate is provided to define a center opening 72 and an annular
opening 74. The bowl structures 124 and 126 are positioned for
metering air flow to the combustion spaced, which is generally
shown by dashed line area 144. As shown, the inner bowl structure
120 has its bottom edge 128 aligned with and positioned above the
top surface of the burner head 24, and the wall of the inner bowl
structure extends upwardly and radially outwardly. The outer bowl
structure 122 has its bottom edge 130 positioned higher than the
bottom edge 128 of the inner bowl structure 120 and lower than the
top edge 124 of the inner bowl structure. The wall of the outer
bowl structure extends upwardly and radially outwardly. The top
edge 126 of the outer bowl structure 122 is positioned higher than
the top edge 124 of the inner bowl structure 120. The top edge of
the outer bowl structure is positioned proximate (e.g., immediately
adjacent or in contact with) the bottom edge of the fin
structures.
[0039] The inner bowl structure may be supported by radially
extending feet that engage the burner head, and the outer bowl
structure may be supported on the inner bowl structure (e.g., via
radially outward extending structure on the inner bowl and
corresponding radially inward extending structure on the outer
bowl). In another implementation the pan unit 142 may include
structure that supports the inner bowl, and the outer bowl may be
supported by either the inner bowl or the pan unit 142.
[0040] Secondary air is delivered to the combustion space 144 via
flow paths 150 and 152 upward through the center of the burner head
24. Secondary air is also delivered to the combustion space 144 via
a flow path 154 between the bottom edge 128 of the inner bowl and
the upper surface of the burner head. Secondary air is further
delivered to the combustion space 144 via a flow path 156 between
the inner and outer bowl. Notably, flow path 154 is radially
outward of the flow paths 150 and 152, and flow path 156 is
radially outward of the flow path 154.
[0041] An alternative embodiment is shown in FIGS. 8-11, where a
plate structure 170 includes radially extending heat exchange fins
172A, 172B on its bottom surface, but no feet for supporting the
plate. Instead, certain fins 172A including a support extension 174
that is configured and sized to rest atop a ring structure 176 of a
support unit 178, which may be of wire rod construction and may or
may not be plated (e.g., nickel plated). Multiple clip structures
180 may be engaged with the support unit 178 to support both the
outer bowl 122 and the inner bowl 120. Similar secondary air flow
paths 150, 152, 154 and 156 to the combustion space 144 are
provided. A vertical central axis 190 of the burner head and
overall arrangement is also shown.
[0042] In the illustrated embodiments, the controlled metering of
secondary air to the combustion space via the defined flow paths
helps to improve combustion efficiency (increasing resultant CO2 in
the flue gas produced through the reduction of excess secondary air
throughout the combustion process). Notably, the flow path 154
feeds secondary air to a cone and/or mantle flame region of the
combustion space. The flow path 156 feeds secondary air to a tail
flame region of the combustion space to help complete combustion.
The bowls act to direct heat by reflection and metering in the
secondary air to help limit outward movement of the flame. The
bowls also provide a shielding and insulating effect that maintains
heat beneath the plate, reducing jacket losses. For example, the
secondary flow through path 156 acts somewhat like an insulating
blanket flow of air. The bowls also help protect the combustion
space 144 from being subject to external environmental issues such
as air movement around the range (e.g., via make-up air, fans used
in the vicinity of the range air movement caused by persons moving
in the vicinity of the range). Additionally, the combination of the
plate and bowls helps prevent any boilover from reaching the burner
head.
[0043] The plate is designed to collect heat from burner flame and
normally exhausted gases and renders the energy to the cooking
utensil that may be positioned atop the plate. The collected and
transferred energy is greater than the sum of open flame contact
and plate to utensil contact losses, therefore yielding thermal
efficiency gains.
[0044] In one implementation of a burner head configuration
designed to operate at an input rate of about 30,000 BTUs, the gap
between the burner head and bottom edge of the inner bowl may, for
example, be on the order of 1/12 to 1/2 inch and the radial
distance between the inner bowl and outer bowl may be on the order
of 1/4 to 3/4 inch. However, variations on these dimension are
possible depending upon a variety of factors such as burner head
size, number and locations of orifices, input rate etc. Flue gas
analysis (e.g., measurement of CO and CO.sub.2) may be used to
determine desirable dimensions in any given instance.
[0045] The subject secondary air metering arrangement may be
provided as a kit for modifying or updating a standard gas burner
arrangement in which a removable grate is positioned above the
burner head. The grate is simply removed and replaced with the
assembly (e.g., the support structure 178, plate 170 and bowls 120
and 122).
[0046] It is to be clearly understood that the above description is
intended by way of illustration and example only and is not
intended to be taken by way of limitation. For example, the inner
and outer bowl 120 and 122 could be formed as a combined structure
(e.g., with the outer bowl including a number of inwardly extending
fingers to which the inner bowl is tack-welded). In another
example, the bowls and plate may all be connected together in a
permanent manner. Moreover, other structures could be produced to
define desired secondary air flow metering into the combustion
space. Other changes and modifications could be made.
* * * * *