U.S. patent number 3,884,413 [Application Number 05/451,216] was granted by the patent office on 1975-05-20 for oven control.
This patent grant is currently assigned to Harper-Wyman Company. Invention is credited to Frank H. Berquist.
United States Patent |
3,884,413 |
Berquist |
May 20, 1975 |
Oven control
Abstract
An oven control particularly useful for ranges having plural
burners and mounted in vehicles includes a single control knob for
manipulation of a manual valve and a thermostatic valve. The
control knob is movable to several manual positions including a
position wherein fuel flow to all burner pilots is shut off, a
position wherein fuel flow is only supplied to a selected burner
pilot such as a range top burner pilot and is shut off to all other
pilots such as an oven burner pilot and a normal off position
wherein all burner pilots are supplied with fuel so that any of the
burners can be utilized. The control knob is also operable to
select a desired burner temperature, which temperature is
maintained by the action of the thermostatic valve and a high
temperature broil setting is provided wherein the oven burner fuel
flow is throttled to provide a thermostatically controlled
modulated burner flame.
Inventors: |
Berquist; Frank H. (Clarendon
Hills, IL) |
Assignee: |
Harper-Wyman Company (Hinsdale,
IL)
|
Family
ID: |
23791283 |
Appl.
No.: |
05/451,216 |
Filed: |
March 14, 1974 |
Current U.S.
Class: |
236/15A;
431/280 |
Current CPC
Class: |
F16K
11/0836 (20130101); F23N 1/007 (20130101); G05G
1/02 (20130101); F16K 5/12 (20130101); F24C
3/128 (20130101); F23N 2235/24 (20200101); F23N
2235/18 (20200101); F23N 2235/12 (20200101); F23N
2241/14 (20200101); F23N 2237/02 (20200101) |
Current International
Class: |
F23N
1/00 (20060101); F16K 11/083 (20060101); F24C
3/12 (20060101); F16K 5/00 (20060101); F16K
5/12 (20060101); F16K 11/02 (20060101); G05G
1/02 (20060101); G05G 1/00 (20060101); F23n
003/06 () |
Field of
Search: |
;236/15A,99
;431/28X |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wayner; William E.
Attorney, Agent or Firm: Mason, Kolehmainen, Rathburn &
Wyss
Claims
What is claimed as new and desired to be secured by Letters Patent
of the United States is:
1. A control valve for use with a gas range having a plurality of
pilot burners for igniting main burners, said valve comprising a
valve body having an inlet for gas and a plurality of outlets for
supplying gas to said pilot burners, a manually operable valve
member carried by said valve body for selectively controlling the
flow of gas between said inlet and said outlets, said valve
including passage means controlled by the position of said valve
member relative to said body for selective communication between
said inlet and said outlets when said valve member is moved between
first, second and third positions, said passage means aligned to
communicate between said inlet and said plurality of outlets in
said first position, aligned to communicate between said inlet and
less than all of said outlets in said second position and aligned
to provide no communication between said inlet and said plurality
of outlets in said third position, and a thermostatic valve means
controlled by the position of said valve member relative to said
body for maintaining a selected temperature range at the main
burner of one of said pilot burners when said valve member is
positioned within a range of automatic temperature controlling
positions, said passage means aligned to communicate between said
inlet and said outlets and a main outlet for supplying gas for one
of said main burners in said temperature controlling range.
2. The control valve of claim 1 wherein said thermostatic valve
means includes thermally responsive means for sensing the
temperature at said one main burner for modulating said valve
means, said passage means including a main fuel flow passage
between said valve member and said main outlet, said thermostatic
valve means positioned to control the fuel flow through said main
passage in response to the temperature condition sensed by said
thermally responsive means.
3. The control valve of claim 2 wherein said passage means includes
a pilot passage between said main fuel passage controlled by said
thermostatic valve means and said outlet for said one pilot burner,
said pilot passage providing fuel flow to said one pilot burner
controlled by said thermostatic valve means in addition to fuel
supplied between said inlet and said one outlet externally of said
main fuel passage.
4. The control valve of claim 3 wherein said thermostatic valve
means includes a valve disk movable toward and away from a valve
seat defined in said main fuel passage, said pilot passage having
one end in communication with said valve seat for supplying
additional fuel to said one pilot burner when said disk is away
from said seat.
5. The control valve of claim 4 wherein said valve disk includes
one or more ports therein and said thermostatic valve means
includes a second valve element movable toward and away from said
disk to modulate fuel flow through said ports when said disk is
seated on said valve seat for sustaining a modulating flame at said
one main burner when said valve member is positioned in a high
temperature broil position.
6. The control valve of claim 5 wherein said passage means includes
a broil passage in communication between said main fuel passage and
said outlet for said one pilot burner when said valve member is in
said broil position for supplying additional fuel for said one
pilot burner.
7. The control valve of claim 2 wherein said passage means includes
a bore defined in said valve body and said valve member is mounted
for rotation in said bore between said first, second and third
positions, and said temperature controlling positions.
8. The control valve of claim 7 wherein said main passage comprises
a hollow bore in said valve member closed at one end and open at an
opposite end in communication with said thermostatic valve
means.
9. The control valve of claim 8 wherein said main passage includes
a slot in said valve member to provide communication between a
portion of an exterior circumferential surface of said member and
said hollow bore and aligned with said inlet of said valve body,
said valve member including an adjoining solid circumferential
portion aligned with and adjacent said slot blocking communication
between said hollow bore of said valve member and said inlet when
said valve member is in said first, second and third positions,
said slot operative to provide communication from said inlet to
said hollow bore when said valve member is in said range of
temperature controlling positions.
10. A control valve for use with a gas range having a plurality of
pilot burners for igniting main burners, said valve comprising a
valve body including a bore in communication with an inlet for gas
and a plurality of outlets for supplying gas to said pilot burners,
a manually operable valve member rotatably mounted in said bore of
said valve body for selectively controlling the flow of gas between
said inlet and said outlets, said valve including first passage
means controlled by the rotative position of said valve member in
said bore for providing selective communication between said inlet
and said outlets when said valve member is moved between first,
second and third manual positions, said first passage means
positioned to communicate between said inlet and said plurality of
outlets in said first position, positioned to communicate between
said inlet and less than all of said outlets in said second
position and positioned to provide no communication between said
inlet and said plurality of outlets in said third position, a
thermostatic valve means also controlled by the rotative position
of said valve member in said bore of said body for maintaining a
selected temperature range at the main burner of one of said pilot
burners when said valve member is rotated within a range of
automatic temperature controlling positions out of said first,
second and third positions, and second passage means in said valve
aligned to communicate between said inlet and a main outlet for
supplying gas for one of said main burners when said valve member
is positioned in said temperature controlling range.
11. The control valve of claim 10 wherein said thermostatic valve
means includes thermally responsive means for sensing the
temperature at said one main burner for modulating said valve
means, said second passage means including a main fuel flow passage
between said valve member and said main outlet, said thermostatic
valve means positioned to control the fuel flow through said main
passage in response to the temperature condition sensed by said
thermally responsive means.
12. The control valve of claim 11 wherein said second passage means
includes a pilot supply passage between said main fuel passage and
said main outlet for said one pilot burner, said pilot supply
passage providing fuel flow to said one pilot burner controlled by
said thermostatic valve means in addition to fuel supplied between
said inlet and said one outlet via said first passage means.
13. The control valve of claim 12 including a thermostatic valve
chamber in said second passage for containing said thermostatic
valve means and in communication between said main fuel passage and
said main fuel outlet, said thermostatic valve means including a
valve disk movable toward and away from a valve seat defined
between said main fuel passage and said valve chamber, said pilot
supply passage having one end in communication with said valve seat
for supplying additional fuel to said one pilot burner via said
first passage means when said disk is away from said seat.
14. The control valve of claim 13 wherein said valve disk includes
one or more ports for communication between said main fuel passage
and said valve chamber, said thermostatic valve means includes a
second valve element movable toward and away from said disk to
modulate fuel flow through said ports when said disk is seated on
said valve seat for sustaining a modulating flame at said one main
burner when said valve member is rotatively positioned in an
automatic temperature controlled broil position.
15. The control valve of claim 14 wherein said valve includes a
second pilot supply passage in communication between said main fuel
passage and said outlet for said one pilot burner, said second
pilot supply passage aligned for supplying additional pilot fuel
for said one pilot burner from said main fuel passage via said
first passage means.
Description
The present invention relates to oven controls and particularly to
an oven control especially useful in ranges having a plurality of
burners and designed to be mounted in vehicles and the like. The
oven control of the present invention is an improvement on the
control shown and described in U.S. Pat. No. 3,563,457, which
patent is assigned to the same assignee as the present
application.
In gas fired ranges designed for use in recreational vehicles,
boats and the like, there is often provided an oven for baking
along with one or more top burner units for frying and boiling. In
modern ranges of this type, one or more pilot burners is used for
ignition of the top burner units and the main gas flow to these top
burners is controlled and adjusted manually. The oven in these
ranges also utilizes a pilot burner for ignition of the main burner
and the main burner is cycled on and off with a thermostatic valve
to maintain a selected temperature.
In some recreational vehicles it is necessary and desirable to
provide for a complete shut off of all fuel flow to the pilots and
oven burners under certain circumstances as for instance when the
vehicle is in motion. In some circumstances it may be desirable to
provide fuel for operation of the top burner pilot so that the top
burners may be used for heating coffee or simple meals, for example
during a brief stop. Since the oven unit of the range is generally
not operated with as high a fuel flow rate as are the top burners
because the oven burner is thermostatically controlled and when the
vehicle is traveling on rough roads or waters it is possible that
the oven pilot may become inoperable or a portion of the pilot
burner structure may even become dislodged. For this reason it is
desirable to provide for complete shut off of the fuel flow to the
oven pilot while the pilot for the top burner is still supplied
with fuel.
It is an object of the present invention to provide a new and
improved oven control, particularly useful in gas fueled ranges
designed for vehicles and the like: to provide an oven control
having a single control knob operable to manipulate a manual valve
through several positions and to control a thermostatic valve in
order that a top burner pilot and an oven burner pilot may be
easily operated: to provide an oven control capable of shutting off
fuel flow to all of the burner pilots and a main oven burner and
having an alternate position wherein fuel flow is supplied to a top
burner pilot but is shut off to an oven burner pilot and a main
oven burner: to provide an oven control for maintaining a selected
temperature setting in an oven and having an additional setting for
use in a high temperature broil operation wherein the flame of the
oven burner is modulated to provide a predetermined broil
temperature in the oven: to provide a plug type valve for use with
LP gas and being capable of withstanding high gas pressure without
danger of leakage or failure in case the pressure regulator of the
fuel system fails.
In brief, one embodiment of the present invention comprises an oven
control for use with a range of the type designed for vehicles
which includes an oven having a pilot operated burner and one or
more pilot operated range top burners. The oven control includes a
single control knob for manipulation of a manual gas valve through
several manual positions and a thermostatically controlled gas
valve for temperature control of an oven burner. The manual
positions include a first position wherein the fuel flow to all of
the burner pilots of the range is shut off, a second position
wherein fuel flow is only supplied to the top burner pilot and is
shut off to the oven burner pilot and a normal, off position
wherein all burner pilots are supplied with fuel so that the top
burner and/or oven burner may be selectively operated when and as
desired. The control knob is also operable to select a desired oven
temperature for controlling the oven burner and the selected
temperature is maintained by the action of a thermostatic valve. A
high temperature broil setting is also provided wherein the oven
burner fuel flow is throttled to provide a thermostatically
controlled modulated burner flame for high temperature broiling in
the oven.
The foregoing and other objects and advantages of the present
invention will appear from the following detailed description and
the claims taken in conjunction with the drawings in which:
FIG. 1 is a schematic isometric diagrammatic illustration of an
oven control embodying the features of the present invention and
illustrated as the control is used in a gas range including top
burners and an oven;
FIG. 2 is a cross sectional view taken substantially along lines
2--2 of FIG. 1;
FIG. 3 is an enlarged isometric exploded diagrammatic illustration
of the plug type valve member of the oven control and is
illustrated along with portions of the gas passages of a range in
which the control is installed, and
FIGS. 4-8 are composite schematic views of the control knob and
several cross sections of the valve manipulated thereby and these
views somewhat schematically illustrate the several operative
positions of the oven control of the present invention.
Referring now more particularly to the drawings and especially to
FIG. 1, therein is illustrated a new and improved oven control
referred to generally by the reference numeral 10 and particularly
well suited for use with a modern LP or natural gas range of the
type often utilized in vehicles and the like. The oven control is
adapted to control and direct the flow of fuel from a source 12
such as a vehicle mounted storage tank for the operation of one or
more top burners 14 and a top burner pilot referred to by the
number 16. The oven control 10 also controls the operation of a
main oven burner 18 and an oven burner pilot 20. Fuel flows to the
top burners 14 through a supply manifold 22 connected to the gas
supply tank 12 and each of the individual top burners is supplied
from the manifold via a separate branch line 24. A manual control
valve 26 is provided in each branch line 24 for direct operator
control of the flame setting for the respective top burners 14 and
the oven control 10 is supplied from the manifold 22 through an
oven control inlet line 28. The oven burner 18 receives fuel from
the oven control 10 through an output line 30 and the oven burner
pilot 20 is supplied with fuel from the oven control through
another output line 32. A safety valve 34 is provided in the oven
burner line 30 and this valve normally remains in the closed
condition until a heat sensitive element 36 positioned adjacent the
oven burner pilot 20 causes the safety valve to open in response to
heat generated by the oven burner pilot. If no flame is present at
the oven burner pilot 20, the safety valve 34 remains closed and
fuel cannot be supplied to the oven burner 18 through the line
30.
The top burner pilot 16 is supplied with fuel from the oven control
10 through an output line 38 and when the top burner pilot 16 is
lit, either of the top burner manual control valves 26 may be used
to supply fuel to the respective top burners 14, which fuel will be
ignited by the pilot flame to provide a cooking flame at the
burner. The top burners 14 are controlled by the setting of the
respective valves 26 to achieve the desired flame for cooking.
In accordance with the present invention, the oven control 10
includes a single control knob 40 mounted at the outer end of a
valve control shaft 42 and provided with an enlarged frustroconical
shaped dial having suitable indicia thereon as indicated in FIGS. 4
through 8. As will be described more fully hereinafter the control
knob 40 is rotatable from a normal OFF position of FIG. 4 wherein
gas is supplied to both the top burner pilot 16 and the oven burner
pilot 20 via the respective lines 32 and 38 in a clockwise
direction to a first manual position labeled TOP PILOTS ON as shown
in FIG. 5 wherein the oven control 10 supplies gas through the line
38 to the top burner pilot 16 only and in this position gas flow to
the oven burner pilot 20 is positively shut off. With the knob in
position of FIG. 5, the operator may use the top burners 14 for
cooking but the oven cannot be used as the oven pilot receives no
fuel. Further clockwise rotation of the knob 40 from the position
of FIG. 5 to the position of FIG. 6 results in the shutting off of
fuel flow to all of the pilots. In the ALL PILOTS OFF position
neither the oven burner pilot nor the top burner pilots can operate
and this position is utilized when it is not desirable that any of
the burners in the range be used, normally because safety factors
don't permit such usage.
The manual positions as illustrated in FIGS. 4, 5 and 6 are
provided in addition to a range of temperature controlled,
automatic oven settings and a high temperature oven broil position
when the knob is rotated in a maximum amount in a counterclockwise
direction from the normal OFF position of FIG. 4 to the high
temperature oven broil position of FIG. 7, marked by the letter B.
In the broil position the top burner pilot 16 is supplied with fuel
so that the top burners may be used and the oven burner pilot 20
and the main oven burner 18 are supplied with fuel in a manner
whereby a temperature controlled modulating flame is provided at
the oven burner in order to accomplish high temperature broiling.
In the range of oven temperature controlling settings, between the
normal OFF position of FIG. 4 and the broil position of FIG. 7, the
knob 40 is rotatable to select a desired oven temperature (the dial
settings are labeled in degrees Fahrenheit from 140.degree. to
500.degree.) and in this range of settings the supply of fuel to
the oven burner 18 via the line 30 is thermostatically controlled
to maintain the selected oven temperature. A temperature sensing
bulb 44 is provided in the oven enclosure, and is in communication
with the oven control 10 through a capillary tube 46 of an oven
sensing unit. The capillary tube is secured to a cylindrical cup
shaped rear housing 48 mounted on the rear face of a rectangular
shaped body 50 of the oven control.
The valve body 50 is provided with an elongated central passage or
bore extending between the front and rear faces thereof and the
bore includes a forward, frustroconically tapered section 52
interconnected by means of an annular groove 54 with an
intermediate small diameter cylindrical bore section 56. The
intermediate bore section is in communication with an enlarged rear
bore section 58 cooperating with the rear housing cup 48 to form a
thermostatic valve chamber 60.
A hollow valve plug or core 62 of matching frustroconical shape is
seated within the forward bore section 52 of the valve body and the
valve plug includes a forwardly extending hollow sleeve 64 in
coaxial telescopic engagement with the inner end portion of a shaft
or stem 42 which carries the knob 40. The stem is biased is an
axial direction outwardly of the valve plug 62 by means of a coiled
spring 67 positioned within the hollow sleeve 64 and having its
outer end seated within a cylindrical recess 42a formed in the
inner end of the stem 42. Outwardly of the recess 42a the stem 42
is formed with a transverse cross bore 42b and a key or groove pin
66 is seated in the transverse bore and extends outwardly from one
side of the stem as best shown in FIG. 2. The key pin 66 is adapted
to seat within a selected one of several positioning grooves which
are defined between radially outwardly extending ridges 68
integrally formed on the inside front wall surface of a front cap
member 70. The cap member is secured to the front face of the valve
body 50 by suitable cap screws 72 and the ridges project radially
outward from a central opening in the front wall of the cap member
which opening accommodates the valve sleeve 64. The front wall also
provides a stop surface for engaging the key pin 66 to limit the
outward travel of the stem 42 under the biasing influence of the
spring 67.
In accordance with the present invention, gas supplied from the
oven control inlet line 28 flows upwardly into a relatively large
main inlet passage 74 which is in communication at its upper end
with the frustroconical bore section 52 intermediate the ends of
the bore section. The frustroconical valve plug 62 is hollow with
an elongated axial bore 62a closed at the forward end of the valve
plug and open at the rear for communication with the annular bore
groove 54 and the intermediate bore section 56 in the valve body.
The valve body is provided with a relatively wide transverse slot
62b through a portion of the wall thereof and the slot is in
alignment with the main inlet passage 74 on a transverse section
plane labeled A, as best shown in the schematic illustrations of
FIGS. 4 through 8. The transverse slot 62b encompasses slightly
more than 180.degree. of the entire circumference of the valve plug
and as shown in FIGS. 7 and 8 when the control knob 40 is rotated
into the broil or bake position, the slot is aligned with the upper
end of the main inlet passage 74 to provide a full flow of fuel
into the interior of the axial bore 62a of the valve plug for use
in supplying fuel for the oven burner and pilot of the range. When
the control knob 40 is positioned in the OFF, TOP PILOTS ON or ALL
PILOTS OFF position, as illustrated in FIGS. 4, 5 and 6, no fuel is
permitted to flow into the axial bore 62a of the valve plug from
the main inlet passage 74 because the transverse slot 62b is not
aligned in communication with the open end of the main inlet
passage. The main inlet passage 74 also supplies pilot burner fuel
via a smaller size passage 76 in communication with the upper end
thereof. The passage 76 supplies fuel through a filter 78 into a
cross passage 80 having an outlet end in communication with the
frustroconical bore section 52 in the valve body at a point spaced
axially rearwardly from the slot 62b in the valve plug toward the
smaller diameter end thereof. At this location (labeled section B
in FIGS. 4-8) the valve plug 62 is formed with a relatively narrow
transverse groove 62c in the outer surface. The groove is closed at
opposite ends and does not communicate with the interior bore 62a
of the valve plug as does the slot 62b. The groove occupies
approximately 300.degree. of circumference around the outer surface
of the valve plug. When the knob is positioned to the OFF, TOP
PILOTS ON, BROIL or BAKE positions of FIGS. 4, 5, 7 and 8
respectively, fuel passes from the cross passage 80 into the groove
62c for distribution to an oven burner pilot supply passage 82
and/or a top burner pilot supply passage 84, dependent upon the
selected position of the valve control knob, as will be described
hereinafter.
Referring to FIG. 3 when the control knob is in the position of
FIGS. 4, 5, 7 or 8, fuel from the cross passage 80 flow via the
groove 62c in the valve plug to the top burner pilot supply passage
84 and this passage supplies fuel to the top burner pilot 16 via
the line 38 which is coupled to the passage 84 on the rear face of
the valve body 50 by a coupling unit 86. To provide for flame
adjustment for the top burner pilot 16, a needle valve pilot
adjustment screw 88 is provided in the passage 84. When the control
knob 40 is in the position shown diagrammatically in FIGS. 4, 7 or
8, pilot fuel is also supplied to the oven burner pilot supply
passage 82 and this fuel flows to the oven pilot burner 20 via a
passage 90 (FIG. 3). The passage 90 is connected to the oven burner
pilot supply line 32 with a coupling unit 92 mounted on the rear
face of the valve body and spaced above the coupling unit 86 for
the top burner pilots.
In accordance with the present invention, with the control knob 40
position in the BROIL position as shown schematically in FIG. 7,
additional fuel is supplied to the oven burner pilot from the
central bore 62a of the valve plug 62. For this purpose the valve
plug is provided with a radial passage 62d in the wall thereof
spaced forwardly of the slot 62b adjacent the larger diameter end
of the valve plug (labeled section C in FIGS. 4-8). When the valve
plug 62 rotated into the BROIL position, fuel passes from the bore
62a of the valve plug out through the passage 62d into a passage 94
in communication with the passage 90 which supplies the oven burner
pilot line 32 (FIG. 3). An adjustable, oven standby orifice sleeve
96 is provided adjacent the junction of the passage 82, 90 and 94
for metering fuel flowing from the passage 82 into the passage 90.
When the control knob 40 is set in the BROIL position in addition
to this metered fuel, additional unmetered fuel from the passage
94, flows around a slot on the exterior of the adjustable orifice
sleeve 96 to the passage 90 and provides additional pilot fuel for
the broiling operation in the oven.
Referring to FIGS. 1, 2 and 3, the main fuel flow to the oven
burner 18 via the line 30 is controlled by an oven sensing element
assembly 98 positioned in the thermostatic valve chamber 60 and
supported from the rear housing 48 by means of a flanged hollow
stud 100 and a coupling nut 102. The capillary tube 46 extends
through the bore of the hollow stud 100 into the valve chamber and
is connected to a diaphragm assembly 104 which expands and
contracts in accordance with the temperature sensed by the oven
temperature sensor unit 44. The diaphragm assembly includes a
cup-shaped cover member 106 and a disk 108 and these members move
toward and away from one another dependent upon the temperature in
the oven. The disk 108 of the diaphragm assembly is attached to a
flanged nib 110 having a threaded stem which is engaged within the
bore of a hollow lead screw 112 coupled to the open end of the
valve plug 62 by a transverse cross pin 114. The cross pin extends
into a transverse longitudinal slot 112a formed at the forward end
of the lead screw to couple the lead screw and nib for rotation
together. The nib 110 includes an enlarged flange 110a for
supporting a cup shaped valve retaining washer 116 and this cup
shaped washer supports and centers the rear end of a coil type
valve seating spring 118 which biases a valve disk 120 toward a
rearwardly facing annular valve surfacce 57 defined in the valve
body between the intermediate bore 56 and the rear bore section 58.
The hollow lead screw 112 includes a radial flange 112b
intermediate its ends and the valve disk 120 is seated against this
flange. As best shown in FIGS. 2 and 3, the valve disk 120 is
formed with a plurality of ports 120a for passing fuel into the
valve chamber 60 from the bore 56 when the valve disk 120 is fully
seated against the seating surface 57. This flow of fuel is further
controlled by a high limit disk 122 also centered on the lead screw
112 and positioned for movement between the valve disk 120 and the
cup shaped washer 116. A high limit coil spring 124 is positioned
between the high limit disk and the cup shaped washer 116 for
biasing the high limit disk toward the valve disk. As shown in FIG.
2, the 122 disk is formed with an annular ridge 122a having a mean
diameter approximately equal to the spacing diameter between the
holes or ports 120a in the valve disk. An annular space is formed
between the surface of the ridge 122a and the valve disk 120 and
this space defines a collecting chamber for the fuel flowing
through the ports 120a of the valve disk when seated. When the fuel
pressure within this chamber is high enough to overcome the bias of
the high limit spring 124, the disk 122 is forced away from the
valve disk 120 and the gas within the annular chamber flows
radially outwardly into the valve chamber 60.
Fuel from the valve chamber flows into the oven burner 18 through
the line 30 by means of a relatively large passage 126 in
communication with one side of the rear bore section 58 of the
valve body. The passage 126 is connected to the oven burner line 30
at the rear face of the valve body via a coupling unit 128. With
the oven control knob 40 in the BAKE position as shown in FIG. 8
and when the oven sensor 44 is calling for heat, additional fuel is
supplied to the dual rate oven pilot 20 from the thermostatic valve
chamber 60 via a bypass passage 130 having one end connected to the
passage 90. The other end of the passage 130 is in communication
with the valve chamber 60 and opens onto the annular valve seating
surface 57 (as best shown in FIG. 3), so that any time the valve
disk 120 is unseated away from the surface 57 additional oven pilot
fuel is supplied by the passage. Fuel flowing from the thermostatic
valve chamber 60 via the passage 130 does not pass through the oven
standby pilot orifice 96 and thus adds unmetered fuel to the dual
rate oven pilot burner 20 like the unmetered additional fuel
supplied by the passage 94 in a broil operation.
Referring now to the schematic diagrams of FIGS. 4 through 8 which
represent the various operating positions of the valve, the
uppermost schematic cross sectional view in the figures (section B)
illustrate a cross section through the valve plug 62 taken adjacent
the smaller diameter end portion in line with the supply passage 80
which supplies filtered fuel for the pilots of system from the main
inlet passage 74. The next lower sectional views (section A) are
taken on a transverse plane at about mid-point through the valve
plug 62 in alignment with the main inlet passage 74 and large slot
62b. Finally, the lowermost sectional views (section C) in FIGS.
4-8 is taken on a cross section aligned with the passage 94 in the
valve body 50 and the port 62d in the valve plug 62.
Referring now specifically to FIG. 6, when the control knob 40 is
in the ALL PILOTS OFF position, the gas flow to the valve chamber
60 from the main inlet supply passage 74 is shut off by the valve
plug and as shown at section B filtered fuel from the passage 80 is
likewise shut off so that no gas is available for the top burner
pilots, oven burner pilots and oven burner.
Referring now to FIG. 5, when the operator of the range desires to
use the top burners only while maintaining the oven pilots off
because of travel over a rough or bumpy road or like, the control
knob 40 is turned to the top pilots ON position. In this position
main gas flow to the interior of the valve plug 62 is still blocked
(section A), however, filtered fuel from the passage 80 is supplied
via the groove 62c in the valve plug to the top burner pilot
passage 84 but not to the oven burner pilot passage 82. In this
position, the top burner pilots may then be utilized for operating
the top burners 14 whenever the manual burner valves 26 are opened
and adjusted to the desired flame level but the oven may not be
used.
Referring now to FIG. 4 when it is desired to use both the top
burners and the oven of the range in a normal manner and to
maintain all pilots operational ready for use, the control knob 40
is rotated to the OFF position. In this position the valve plug 62
again blocks the flow of gas into the chamber 60 until such time as
the control knob is moved into a range of BAKE positions (FIG. 8)
where a selected temperature is desired or into the BROIL position
(FIG. 7). In the OFF position (FIG. 4), the supply of filtered fuel
from the passage 80 is directed into the groove 62c of the valve
plug and flows into the respective pilot supply passages 82 and 84
connected to the oven burner pilot and the top burner pilot. These
pilots may then be lit and maintained in readiness for igniting the
top burners and the oven burner when desired.
When it is desired to use the oven in a baking operation a selected
temperature is chosen by rotating the knob 40 to the desired
setting (FIG. 8) and when this occurs, the slot 62b on the valve
plug is aligned with the main inlet passage 74 to supply fuel to
the interior bore 62a of the valve plug. This fuel flows toward the
valve chamber 60 and flow is controlled by the operation of the
valve disk 120 and high limit disk 122. When the knob 40 is set to
any selected temperature in the range of 140.degree. to
500.degree., fuel is also supplied from the passage 80 and moves
through the pilot passages 82 and 84 and the oven burner pilot 20
is operated at a standby pilot rate. The main gas flow to the oven
burner is thermostatically controlled by the valve disk 120 which
moves in accordance with the temperature sensed and transmitted to
the diaphragm assembly 104. From the thermostatic valve chamber 60
the fuel flows via the passage 126, coupling 128 and line 30 to the
oven burner safety valve 34. When the oven pilot is operative the
safety valve is opened and the gas flows to the burner 18. At the
same time, when the valve disk 120 is spaced away from the seating
surface 57 gas is also supplied to the oven pilot burner 20 via the
passages 130, 90, coupling 92 and line 32. Once the temperature
selected by the control knob 40 is obtained, the valve disk 120
tends to seat against the surface 57 and the gas flow is reduced so
that the oven burner shuts off until the oven is again calling for
heat. When the valve disk 120 is away from the seat 57, fuel is
supplied to the oven burner pilot 20 at a metered or standby rate
via the by passage 84 with a flow of filtered gas and additional
fuel flows to the oven pilot via the passage 130.
When the control knob 40 is in any of the positions shown in FIGS.
4, 5, 6 and 8, at section C on the valve plug 62, no flow is
provided because the port 62d is not in alignment with the passage
94 which supplies additional fuel to the oven burner pilot for a
broiling operation. When the control knob 40 is then moved to the
BROIL position, as illustrated in FIG. 7, the port 62d in the valve
plug 62 becomes aligned with the passage 94 and this provides
additional pilot fuel to the oven pilot burner 20 even though the
valve disk 120 may be seated. In this conductive filtered gas is
constantly flowing to the oven pilot at a metered rate through
orifice member 96. In the BROIL position, the gas flow to the oven
burner is modulated by the high limit disk 122 in order to provide
a modulating broiling flame for high temperature operation. In the
BAKE position, the oven burner is cycled on and off to maintain a
selected temperature. In the BROIL position, however, the oven
burner remains on but the flow of fuel is modulated to maintain the
high broil temperature.
Although the present invention has been described with reference to
a single illustrative embodiment thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this invention.
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