U.S. patent application number 10/153409 was filed with the patent office on 2002-09-26 for portable griddle stove with dual cooking surfaces.
Invention is credited to Lawhon, Robert L., May, Randall L., Mosher, Robert F. II, Neugebauer, Norman D..
Application Number | 20020134250 10/153409 |
Document ID | / |
Family ID | 23463219 |
Filed Date | 2002-09-26 |
United States Patent
Application |
20020134250 |
Kind Code |
A1 |
Mosher, Robert F. II ; et
al. |
September 26, 2002 |
Portable griddle stove with dual cooking surfaces
Abstract
A portable griddle stove has two non-stick cooking surfaces,
either of which can withstand being on the underside of the cooking
surface in use and the heat applied to the underside surface. A
heat shield and heat diffuser control the temperature applied to
the underside of the cooking surface by providing radiant heat to
the center portion of the cooking surface and cooling the
combustion gas diffused to the perimeter of the cooking surface.
Secondary air provided through openings in case the and heat shield
assist in cooling the combustion gas.
Inventors: |
Mosher, Robert F. II;
(Wichita, KS) ; Neugebauer, Norman D.; (Wichita,
KS) ; May, Randall L.; (Andover, KS) ; Lawhon,
Robert L.; (Andover, KS) |
Correspondence
Address: |
Kramer Levin Naftalis & Frankel LLP
919 THIRD AVENUE
NEW YORK
NY
10022
US
|
Family ID: |
23463219 |
Appl. No.: |
10/153409 |
Filed: |
May 22, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10153409 |
May 22, 2002 |
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09796970 |
Mar 1, 2001 |
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09796970 |
Mar 1, 2001 |
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09371262 |
Aug 10, 1999 |
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6267047 |
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Current U.S.
Class: |
99/339 ; 99/340;
99/400; 99/446 |
Current CPC
Class: |
A47J 37/0786 20130101;
A47J 37/0713 20130101 |
Class at
Publication: |
99/339 ; 99/340;
99/400; 99/446 |
International
Class: |
A23L 001/00; A47J
037/08; H05B 001/00 |
Claims
What is claimed is:
1. A stove, comprising: a housing; a heat distribution system
disposed in the housing; and a griddle removably connected to the
housing; wherein the griddle includes a first side having a first
non-stick cooking surface and a second side opposite the first
side, the second side having a second non-stick cooking surface,
one of the first side and the second side being facing towards the
heat distribution system.
2. The stove according to claim 1, wherein the heat distribution
system includes a heat shield connected to the housing, a tube
burner disposed above the heat shield and a heat diffuser disposed
above the tube burner.
3. The stove according to claim 2, wherein the heat diffuser
includes a center portion adjacent two angled portions, each of the
two angled portions having a plurality of projections, a plurality
of openings being formed between adjacent projections.
4. The stove according to claim 1, further comprising a handle
attached to each end of the housing, a drip tray being removably
coupled to the handle at one end of the housing.
5. The stove according to claim 4, wherein an opening extends
through the first side and second side of the griddle, a plurality
of protrusions being arranged along a perimeter of the opening, the
opening being disposed above the drip tray.
6. The stove according to claim 1, further comprising venturi
assembly connected to the heat distribution system and a regulator
assembly connected to the venturi assembly.
7. The stove according to claim 6, wherein the venturi assembly
includes a cylindrical portion having a circumferential groove, a
portion of the circumferential groove being removed to form a slot,
a spring clip being removably disposed in the groove.
8. The stove according to claim 7, wherein the regulator assembly
includes a connector having a profiled edge adjacent a
circumferential groove, the connector releasably engaging the
cylindrical portion of the venturi assembly, the profiled edge
releasably engaging a flat portion of the spring clip disposed in
the slot, the flat portion of the clamp also being disposed in the
circumferential groove of the connector.
9. The stove according to claim 7, wherein the spring clip includes
a flat portion.
10. A connector assembly, comprising: a first mating portion
including a cylindrical portion having a circumferential groove, a
portion of the circumferential groove being removed to form a slot,
a spring clip being removably disposed in the groove; and a second
mating portion having a first profiled edge adjacent a
circumferential groove, the second mating portion releasably
engaging the cylindrical portion of the first mating portion, the
first profiled edge releasably engaging a flat portion of the
spring clip disposed in the slot, the flat portion of the clip also
being disposed in the circumferential groove of the second mating
portion.
11. The connector assembly according to claim 10, further including
a second profiled edge adjacent the circumferential groove of the
second mating portion, the second profiled edge forming a greater
angle than the first profiled edge so as to inhibit disengagement
of the first mating portion and the second mating portion.
12. A heat distribution system, comprising: a heat shield connected
to a housing; a burner disposed above the heat shield; and a heat
diffuser disposed above the tube burner.
13. The heat distribution system according to claim 12, wherein the
heat diffuser includes a center portion adjacent two angled
portions, a plurality of projections extending from each of the two
angled portions, a plurality of openings being formed between
adjacent projections.
14. The heat distribution system according to claim 13, wherein the
center portion is disposed at a level lower than a level of the
plurality of projections.
15. A griddle, comprising: a substrate; a first cooking surface
disposed on a first side of the substrate; and a second cooking
surface disposed on a second side of the substrate opposite the
first side, wherein each of the first cooking surface and the
second cooking surface include a non-stick surface coating.
16. The griddle according to claim 15, wherein the substrate is
formed of one of cast iron and cast aluminum.
17. The griddle according to claim 15, wherein the first surface
includes a plurality of ribs extending substantially along a length
of the first cooking surface.
18. The griddle according to claim 15, wherein the second cooking
surface includes a plurality of ribs extending along a portion of
the second cooking surface, a remainder of the second cooking
surface being substantially flat.
19. The griddle according to claim 15, wherein a perimeter of the
first cooking surface and the second cooking surface include a
raised edge.
20. The griddle according to claim 15, wherein an opening is
disposed through the first cooking surface, the substrate and the
second cooking surface.
21. The griddle according to claim 20, wherein a plurality of
protrusions are formed along an inner edge of the opening.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a portable griddle stove,
more particularly to a portable griddle stove with dual cooking
surfaces.
BACKGROUND INFORMATION
[0002] Cooking devices used for camping and other outdoor
activities are well known in the art. For example, The Coleman
Company, Inc. of Wichita, Kans. has been manufacturing portable
cooking stoves for many years. Such portable cooking stoves
include, for example, one or two burners supplied with propane by
an attachable tank. Such a portable stove provides direct flame
impingement on the cooking surface placed on the burner, generally
a pot or skillet. Direct flame impingement does not present a
problem in this circumstance as the pot or skillet is designed to
withstand the heat from the flames. Even pots or skillets that
include a non-stick coating on the cooking surface, such as
TEFLON.RTM. manufactured by DuPont of Delaware, can be used with
the portable stove as the underside of the pot or skillet is
untreated metal that can withstand the direct flame impingement,
whereas a non-stick surface could not withstand the high
temperature from direct flame impingement. In addition, portable
stoves generally do not provide a cooking surface and if a cooking
surface is provided, the cooking surface is often treated with a
non-stick coating and thus cannot be reversible as the underside
would then have a non-stick coating that would be damaged from the
heat.
[0003] Another type of portable cooking device is a barbecue grill,
whether fueled by charcoal, natural gas or propane. While a
barbecue is often portable, it is not suitable for use indoors due
to safety reasons and size limitations. Further, the cooking
surface for a barbecue grill is generally a metal grill that
provides sufficient support for the food to be cooked while
allowing the heat from the charcoal or burners to pass directly
through the grill to cook the food. Barbecue grills generally do
not provide a solid cooking surface such as griddle surface.
[0004] There do exist reversible cooking surfaces, such as a cast
iron griddle manufactured by the Lodge Manufacturing Company that
provides a cast iron plate that can be placed over a heat source
such as flames from a campfire, either side of the cast iron plate
providing a cooking surface such as a flat surface on one side and
a grooved surface on another side. Such a plate, however, cannot
have a non-stick coating on both sides of the griddle that would be
exposed to high temperatures.
[0005] A popular cooking surface that is not suitable for portable
or outdoor use is an electric griddle. An electric griddle usually
includes a non-stick cooking surface that is heated on its
underside by an electrically heated coil. Such an electric griddle
requires a source of alternating current electrical power that is
often not available for convenient portable or outdoor use, such as
when camping or hiking.
[0006] Thus, it is desirable to have a portable cooking system that
provides two non-stick cooking surfaces.
SUMMARY OF THE INVENTION
[0007] A portable cooking system includes a tube burner and a
diffuser disposed above the tube burner providing radiant heat to
the center portion of the cooking surface and directing combustion
gas towards the perimeter of the cooking surface. A secondary air
flow system provides secondary air to mix with the diffused
combustion gas to control the temperature of the combustion gas
impinging on the perimeter of the cooking surface. As a result of
the diffuser and the secondary air flow system, the temperature of
the heat applied to the underside of the cooking surface in use can
be controlled to allow the underside surface to have a non-stick
coating.
BRIEF DESCRIPTION OF THE DRAWING
[0008] FIG. 1 illustrates an exploded view of an exemplary griddle
stove according to an embodiment of the present invention.
[0009] FIGS. 2A and 2B illustrate exemplary cooking surfaces
according to an embodiment of the present invention.
[0010] FIG. 3 illustrates an exemplary connection of a venturi
assembly according to an embodiment of the present invention.
[0011] FIG. 4 illustrates an exemplary ignition system according to
an embodiment of the present invention.
[0012] FIG. 5 illustrates an exemplary regulator assembly connector
according to an embodiment of the present invention.
[0013] FIG. 6 illustrates an exemplary heat shield assembly
according to an embodiment of the present invention.
[0014] FIG. 7 illustrates an exemplary case according to an
embodiment of the present invention.
[0015] FIG. 8 illustrates an exemplary opening in a cooking surface
according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0016] As illustrated in FIG. 1, a griddle stove according to an
exemplary embodiment of the present invention includes, for
example, a chassis, a fuel delivery system, an electronic ignition
system, a heat distribution system and cooking surfaces. The
chassis includes, for example, a case 6, leg brackets 3, 4 and
handles 7. Handles 7 have, for example, universal design so that a
particular handle 7 can be used on either end of the griddle. The
particular appearance and structure of handles are a matter of
design choice provided that adequate support is provided for the
case 6 and other components of the grill. The leg brackets 3, 4 and
handles 7 are formed of, for example, glass filled nylon, such as
polyester thermoplastic, flame retardant, 30% glass which has high
heat properties and moderate cost, although other suitable material
could be used. The leg brackets 3, 4 provide exemplary means to
connect the handles 7 to case 6 and also provide stiffness to the
case 6 as well as thermal isolation between the case 6 and the
handles 7. Case 6 is formed of, for example, cold rolled steel,
draw quality, and can be painted with heat-resistant paint if
desired. The chassis also provides structural support for the other
components of the griddle as described below.
[0017] FIGS. 2A and 2B illustrate two exemplary cooking surfaces
21, 22 disposed on opposite sides of griddle 10. Griddle 10 is
formed of, for example, cast aluminum having a nonstick surface
coating, such as TEFLON, on cooking surfaces 21 and 22. Griddle 10
can attach to case 6 by, for example, a slip fit or other suitable
connection means.
[0018] Cooking surface 21 includes a series of raised ribs
extending substantially the length of cooking surface 21 while
cooking surface 22 includes a flat cooking area 24 and a series of
shorter raised ribs disposed at an end area of the cooking surface.
The configuration of the cooking surfaces 21, 22 are merely
illustrative as any desired pattern can be provided on a particular
cooking surface. By having two cooking surfaces 21, 22, the need to
carry additional cooking supplies when camping, such as a griddle
for pancakes and a grill or fish or meat, is minimized.
[0019] According to an exemplary embodiment of the present
invention, griddle 10 includes a roughly circular opening 25.
Because griddle 10 in an embodiment of the present invention
includes two cooking surfaces 21, 22, both cooking surfaces 21, 22
can generate grease when in use, such as from frying bacon.
Accordingly, the grease has to be withdrawn from the cooking
surface to avoid spillage and undesired flare-up as well as drawing
the grease away from the food being cooked. It is preferable for
the grease to drip directly downward into drip tray 1 which is
removably attachable to handle 7. Opening 25 is provided in cooking
surfaces 21, 22 for waste removal.
[0020] As shown in FIG. 1, drip tray 1 connects to handle 7 and
extends under the cooking surface 21, 22 (dimple). The connection
between drip tray 1 and handle 7 can be via, for example, tabs on
drip tray 1 that lock into corresponding holes in handle 7. Drip
tray 1 is made of, for example, the same material as handle 7. To
achieve the desired flow of waste through opening 25 and into drip
tray 1, a series of bumps 26 or other suitable protrusions are
disposed, for example, around the perimeter of opening 25 which
induce the waste flowing through the opening 25 to form drops and
fall directly into drip tray 1 instead of running along the
undersurface of griddle 10. The bumps or protrusions 26 provide a
specific path for the liquid to follow through opening 25.
[0021] According to an exemplary embodiment of the present
invention, not only can two different cooking surfaces be provided
on a single griddle 10, but also each cooking surface can have a
non-stick coating that is not damaged when the cooking surface not
in use is exposed to heat from the heat distribution system. As
illustrated in FIG. 1, the heat distribution system includes, for
example, heat shield 13, tube burner 15 and heat diffuser 11.
[0022] Tube burner 15 is conventional as is known in the art and
includes a plurality of openings along two sides to emit the
air-fuel mixture to be ignited upon emission from the openings of
tube burner 15. Tube burner 15 may be made of aluminized steel or
other suitable material. Heat shield 13 is disposed below tube
burner 15 and connected to case 6 for support. Heat shield 13
minimizes heat transfer to the case 6 by acting as a radiant
shield, thereby allowing safe tabletop temperatures with a low
profile. Heat shield 13 can be manufactured of, for example,
aluminized steel and could also be aluminum, stainless steel or a
plated steel. The heat shield 13 channels secondary air to tube
burner 15 as described below.
[0023] Heat diffuser 11 acts as a barrier between the tube burner
15 and the undersurface of the griddle 10 (e.g., the cooking
surface 21, 22 not in use). The heat diffuser 11 prevents, for
example, flames from the tube burner 15 from impinging directly on
the non-stick coating on the undersurface of the griddle 10 and
spreads the combustion gases towards the perimeter of the griddle
10. Heat diffuser 11 can be made of, for example, stainless steel,
such as 430 stainless steel due to the desire to have the diffuser
resist corrosion and withstand high temperatures, although cold
rolled steel also could be used but may present corrosion
problems.
[0024] As illustrated in FIG. 1, heat diffuser 11 has side portions
112 that extend upwards towards griddle 10 and angle towards the
perimeter of griddle 10. In addition, the projections 10 on the
diffuser 11 are configured to form openings 111 between adjacent
projections 110 that have a quasi V-shape. For example, the
openings 111 could have an approximately 8 degree opening.
[0025] In operation, combustion gas (e.g., propane ignited upon
exit from the tube burner 15) provides a flame that naturally flows
upwards towards the side portions 112 of heat diffuser 11. By
angling side portions 112 upwards, the side portions 112 are
optimally positioned to receive maximum heating from the flames.
The flames from tube burner 15 heat the side portions 112 of
diffuser 11 which in turn provides radiant heat towards the center
portion of griddle 10. Thus, there is little, if any, direct flame
impingement on the center of griddle 10, the use of radiant heat
from diffuser 11 protecting the non-stick coating on the
undersurface of griddle 10.
[0026] Since the heat generated by the combustion gas is greatest
at the center portion of the griddle 10 and decreases towards the
perimeter of the griddle, the projections 110 of diffuser 11 push
the combustion gas away from the center of the griddle 10. Openings
111 between projections 110 allow some combustion gas to escape
towards the undersurface of griddle 10 for heating purposes while
the projections 110 push the combustion gas further towards the
perimeter of the griddle 10 to achieve even heating of the entire
cooking surface 21, 22 instead of concentrating the heating in the
center portion of the griddle 10.
[0027] Even with the projections 110 pushing the combustion gas
towards the perimeter of the griddle 10, the combustion gas may not
be sufficiently cooled and could damage the nonstick coating on the
undersurface of the griddle 10. Accordingly, in an exemplary
embodiment of the present invention, a secondary air system is
utilized. Referring to FIG. 6, heat shield 13 includes, for
example, a center portion 132 and two edge portions 131, 133
extending from either side of center portion 132 and angled upwards
so as to be angled towards burner tube 15 (e.g., see FIG. 1).
Center portion 132 includes, for example, a series of openings 134
disposed below tube burner 15. Openings 134 channel secondary air
to the tube burner 15. Some additional air may be available from a
gap between the undersurface of griddle 10 and upper portion of
case 6 adjacent to the handle. With no additional airflow to mix
with the combustion gas, however, the combustion gas could be
sufficiently hot to damage the underside of the non-stick cooking
surface as well as the bottom pan of the grill (e.g., a painted
surface on the bottom of case 6 could burn).
[0028] Accordingly, a secondary air system is utilized according to
an exemplary embodiment of the present invention. Edge portions
131, 133 of heat shield 13 include, for example, openings 135 that
provide additional air flow to cool the combustion gas that is
pushed to the perimeter of the griddle 10 by the heat diffuser 11.
Openings 135 are arranged to create a flow of air between openings
135 and openings 60 in the bottom of case 6, as illustrated in FIG.
7. For example, openings 134 and 135 in heat shield 13 are arranged
offset from openings 60 in case 6 to provide an airflow path.
Openings 134 and 135 are generally not aligned with openings 60 to
prevent a direct path for heat radiation to the tabletop or other
surface on which the stove is placed. Alignment of openings could
generate a hotspot on the underlying surface and create a safety
problem.
[0029] Accordingly, openings 60 in case 6 and openings 134, 135 in
heat shield 13 allow fresh air into the grill and can be arranged
as a function of offset placement of the openings to channel fresh
air to predetermined locations so, for example, the fresh air
interacts with the combustion gas towards the perimeter of the
diffuser 11. It is further noted that by angling the edge portions
131, 133 of heat shield 13 towards tube burner 13 and the perimeter
of griddle 10, the mixing of the secondary air with the combustion
gas not only cools the combustion gas to a safe temperature for
interaction with the underside of the cooking surface, but also
causes the volume of combustion gas to expand, thus causing the
combustion gas to expand above the heat diffuser 11 to safely heat
the perimeter of the cooking surface 21, 22. The combination of the
heat diffuser 11 and heat shield 13 also dilutes the combustion
gases to cool and disperse the heat generated by tube burner 15 so
as to not harm the underside cooking surface 21, 22 and provide
even heating of the griddle 10.
[0030] The fuel delivery system includes, for example, a
conventional regulator assembly 14 that connects to a propane tank
(not shown), and a venturi assembly 12 connected to a tube burner
15. Fuel is provided, for example, by a propane tank (not shown)
attached to the regulator assembly 14, such as a portable propane
tank manufactured by The Coleman Company, Inc. of Wichita, Kans.
According to an exemplary embodiment of the present invention, the
regulator assembly 14 connects to the venturi assembly 12 via, for
example, spring clip 36. In this case, no clocking of the regulator
assembly 14 or threading is required compared to a conventional
connection which employs a threaded connection or notch and lock
mating between the regulator and the burner tube 15 via the venturi
assembly 12.
[0031] As illustrated in FIGS. 3 and 5, according to an exemplary
embodiment of the present invention, venturi assembly 12 is
generally cylindrical with a tube mating portion 30 that attaches
to the tube burner 15 via, for example, a slip fit. An alternative
connection could be, for example, a press fit or threaded
connection. Adjacent to tube mating portion 30 is a center portion
31 including openings 32. Openings 32 allow air to mix with the
fuel that passes through center portion 31. Towards one end of
center portion 31, a groove 33 extends around the circumference of
the center portion 31. Along a portion of the circumference of
groove 33, for example 90.degree. of the circumference of groove
33, material is completely removed (e.g., a slot is milled) so that
an opening extends around a portion of the circumference of center
portion 31. Accordingly, groove 33 can releasably receive a spring
clip 36 having a flat portion 37 and cylindrical portion 38, the
flat portion 37 being disposed in the opening in groove 33. Flange
34 bears against the backside of cover 8 to prevent venturi
assembly 12 from slipping out of tube burner 15. End portion 35
protrudes through cover 8 to provide the point of connection for
connector 50 of regulator assembly 14.
[0032] As shown in FIG. 5, connector 50 of regulator assembly 14
includes, for example, hexagonal portion 51 providing a threaded
connection to a connector tube of regulator assembly 14
transporting fuel towards the venturi assembly 12. Adjacent to
hexagonal portion 51 is, for example, a cylindrical center portion
52. Groove 53 having, for example, a profiled edge 53A, is disposed
between center portion 52 and gastip 54 and extends the
circumference of center portion 52. Gastip 54 includes, for
example, a profiled edge 54A. In an embodiment of the present
invention, profiled edge 54A forms a lesser angle with respect to
horizontal than profiled edge 53A.
[0033] Thus, in operation gastip 54 of connector 50 is inserted
into end portion 35 of venturi assembly 12. When gastip 54 is
inserted into venturi assembly 12, profiled edge 54A engages spring
clip 36, which is disposed in groove 33, the flat portion 37 of
spring clip 36 extending through the opening in groove 33. With
sufficient force applied to connector 50, profiled edge 54A passes
under spring clip 36 and flat portion 37 engages groove 53 in
connector 50. As a result, regulator assembly 14 is held in place
in venturi assembly 12 by spring clip 36. To remove connector 50,
force is applied to connector 50 to extract it from venturi
assembly 12, the force required generally being greater for removed
than insertion due to the steeper edge 53A having to be overcome.
According to an exemplary embodiment of the present invention
employing such a spring clip connection or other similar
connection, operation of the portable grill is simplified and the
orientation of the fuel tank is no longer relevant. Connector 50
and venturi assembly 12 can be made of, for example, brass or
plated steel. It will be appreciated by those skilled in the art
that the above described connection of venturi assembly 12 and
connector 50 can be utilized for connecting other components in a
similar manner.
[0034] The ignition system according to an exemplary embodiment of
the present invention is conventional as is known in the art. The
ignition system includes, for example, an ignition box 16, an
electrode 17, a piezoelectric igniter 18 and a grounding strap 5 as
illustrated in FIGS. 1, 4 and 6. The electrode 17 attaches to the
ignition box 16 with, for example, a screw, forming a spark gap
through which a portion of the fuel-air mixture flows. The
piezoelectric igniter 18 attaches to the cover 8 with, for example,
igniter bracket 9 and screws. The grounding strap 5 attaches to the
cover and provides grounding to the chassis. Button cover 2 may
press into the cover to conceal the tip of the piezoelectric
igniter 18.
[0035] Thus, according to an exemplary embodiment of the present
invention, a portable griddle stove is provided that has two
non-stick cooking surfaces 21, 22, either of which can withstand
being on the underside of the cooking surface in use and the heat
applied to the underside surface. A heat shield 13 and heat
diffuser 11 control the temperature applied to the underside of the
cooking surface by providing radiant heat to the center portion of
the cooking surface 21, 22 and cooling the combustion gas diffused
to the perimeter of the cooking surface 21, 22. Secondary air
provided through openings in case 6 and heat shield 13 assist in
cooling the combustion gas.
* * * * *