U.S. patent application number 11/417194 was filed with the patent office on 2006-11-23 for gas flow control system for gas barbeque and the like.
This patent application is currently assigned to Pioneering Technology Inc.. Invention is credited to Reza H. Shah.
Application Number | 20060260603 11/417194 |
Document ID | / |
Family ID | 37441473 |
Filed Date | 2006-11-23 |
United States Patent
Application |
20060260603 |
Kind Code |
A1 |
Shah; Reza H. |
November 23, 2006 |
Gas flow control system for gas barbeque and the like
Abstract
A gas control system having: a valve body having a preliminary
chamber, an inlet orifice in communication with said preliminary
chamber, an outlet orifice on said valve body in communication with
a gas burning device, a main chamber within said valve body, said
main chamber and said preliminary chamber communicating through a
valve opening, a stopper in said preliminary chamber and normally
urged by a compression spring located in said preliminary chamber
to engage with said valve opening to close communication between
said preliminary chamber and said main chamber, an elongated
slidable rod slidably mounted in said valve body and having an
inner end portion juxtaposed with said stopper washer, and a
pressing arm juxtaposed with another end of said slidable rod and
operative for pressing said slidable arm inwards to disengage said
stopper washer from said valve opening for releasing the gas in
said preliminary chamber into said outlet orifice.
Inventors: |
Shah; Reza H.; (Acton,
CA) |
Correspondence
Address: |
OGILVY RENAULT LLP
1981 MCGILL COLLEGE AVENUE
SUITE 1600
MONTREAL
QC
H3A2Y3
CA
|
Assignee: |
Pioneering Technology Inc.
|
Family ID: |
37441473 |
Appl. No.: |
11/417194 |
Filed: |
May 4, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60677819 |
May 5, 2005 |
|
|
|
Current U.S.
Class: |
126/41R |
Current CPC
Class: |
F23N 2235/24 20200101;
F23N 2235/14 20200101; F23N 2223/38 20200101; F23N 2235/18
20200101; F24C 3/12 20130101; A47J 37/0713 20130101 |
Class at
Publication: |
126/041.00R |
International
Class: |
F24C 3/00 20060101
F24C003/00 |
Claims
1. A gas control system comprising: a valve body having a
preliminary chamber, an inlet orifice in communication with said
preliminary chamber, an outlet orifice on said valve body in
communication with a gas burning device, a main chamber within said
valve body, said main chamber and said preliminary chamber
communicating through a valve opening, a stopper in said
preliminary chamber and normally urged by a compression spring
located in said preliminary chamber to engage with said valve
opening to close communication between said preliminary chamber and
said main chamber, an elongated slidable rod slidably mounted in
said valve body and having an inner end portion juxtaposed with
said stopper washer, and a pressing arm juxtaposed with another end
of said slidable rod and operative for pressing said slidable arm
inwards to disengage said stopper washer from said valve opening
for releasing the gas in said preliminary chamber into said outlet
orifice.
2. A gas control system according to claim 1 including a stepping
motor mounted to said valve body, said pressing arm being mounted
to a rotary shaft of said stepping motor whereby rotation of said
motor pivots said pressing arm to press said slidable arm inwards
of said valve body.
3. A gas control system according to claim 2 wherein said outlet
orifice is connected to gas burners and pilot flame units.
4. A gas barbeque control system comprising: a valve body having a
preliminary chamber for receiving the gas for operating said
barbeque, an inlet orifice provided on said valve body operative by
an electromagnetic control member for admitting gas into said
preliminary chamber; an outlet orifice provided on said valve body
operative for directing the gas to gas burners in said barbeque
from a main chamber in said valve; a pilot orifice provide on said
valve body operative for directing the gas to flow to a pilot flame
gas tube of said barbeque; a first valve opening located between
said preliminary chamber and said pilot orifice; a first stopper
washer located in said preliminary chamber and normally biased by a
first compression spring to engage with said first valve opening;
said electromagnetic control member being operative for disengaging
said first stopper washer from said first opening whereby the gas
in said preliminary chamber flows to said pilot flame gas tube
through said pilot orifice.
5. A gas barbeque control system according to claim 3 including a
second valve opening located between said preliminary chamber and
said main chamber, an elongated slidable rod mounted in said valve
body, a bushing mounted on said slidable rod and operative by said
slidable rod to engage and disengage with said second valve opening
selectively.
6. A gas barbeque control system according to claim 5 including a
compression spring located in said main chamber and normally
applying a spring force for urging said bushing towards said second
valve opening.
7. A gas barbeque control system according to claim 6 including a
pressing arm juxtaposed to an outer end of said slidable rod and
operative for pressing said rod inwards to engage said bushing with
said second valve opening.
8. A gas barbeque control system according to claim 7 including a
ring washer fixedly mounted on a middle portion of said elongated
slidable rod located within an inner chamber of said valve body, a
second compression spring located in said inner chamber and
cooperative with said ring washer and an end wall of said inner
chamber for normally urging said slidable rod to extend outward of
said valve body whereby disengaging said bushing from said second
valve opening when said pressing arm is not pressing said rod
inwards whereby gas in said preliminary chamber flows into said
main chamber to exit said outlet orifice.
9. A gas barbeque control system according to claim 8 including a
stepping motor mounted to said valve body, and said pressing arm is
a pivotal arm having one end mounted to a rotary shaft of said
stepping motor and a free end portion juxtaposed with said outer
end of said slidable rod.
10. A gas barbeque control system according to claim 9 including a
mechanical button mounted on said outer end of said slidable rod
and operative manually for pressing said slidable rod inwards of
said valve body.
11. A gas barbeque control system according to claim 9 wherein said
pressing arm is a slidable plunger of an electromagnetic solenoid
operative for pressing said slidable rod inwards of said valve
body.
12. A gas barbeque control system according to claim 8 including a
remote control system having a sensing and control unit mounted on
said barbeque and a remote selection unit, said sensing and control
unit and remote selection unit communicative with one another
through a transmitter in each unit, said sensing and control unit
having a temperature sensor mounted on said barbeque, a comparator
means operative for comparing electrical signal from said
temperature sensor and from said stepping motor for providing a
status signal indicative of temperature condition of said barbeque,
said status signal being transmitted to said remote selection
unit.
13. A gas barbeque control system according to claim 12 wherein
said remote selection unit having a temperature setting means
operative for generating a selection signal indicative of a
desirable temperature of said barbeque, a second comparator means
in said remote selection unit operative for comparing said
selection signal with said status signal transmitted to said remote
selection unit to generate a control signal transmitted back to
said sensing and control unit for operating said pressing arm to
press on said slidable rod in a selected manner to vary amount of
said gas flowing through said second valve opening to said outlet
orifice and in turn setting the degree of flame of said burners of
said barbeque.
14. A gas barbeque control system according to claim 8 including a
motor control device connected to said stepping motor and being
operative for rotating in a clockwise direction and
counterclockwise direction selectively for varying amount of said
slidable rod pressing into said valve body for varying the amount
of gas flowing to said burners of said barbeque.
15. A gas barbeque control system according to claim 8 wherein said
pilot flame gas tube having pilot flame openings located adjacent
to said gas burners, and sparker devices located adjacent to said
pilot flame openings and being operative for igniting the gas
emitting from said pilot flame openings.
16. A gas barbeque control system according to claim 15 wherein
said motor control device is operated by batteries, and a low
battery inhibitor is included therein to render said motor control
device operative only when said batteries have sufficient power to
operate said control system through a complete cycle.
17. A gas barbeque control system according to claim 1 wherein said
valve body includes a first body portion and a second body portion,
said inlet orifice and outlet orifice being provided in said first
body portion and a pilot orifice provided in said second body
portion, said preliminary chamber and said main chamber being
located in said first body portion, and an intermediate chamber and
pilot gas outlet chamber located in said second body portion, a
first valve opening located between said preliminary chamber and
said main chamber, and a second valve opening located between said
intermediate chamber and pilot outlet chamber, a first spring
biased valve seat located in said preliminary chamber and operative
to close said first valve opening normally, a second spring biased
valve seat located in said intermediate chamber and operative to
close said second valve opening normally, a first elongated rod
slidably mounted in said first body portion, and a second elongated
rod slidably mounted in said second body portion, a seesaw bar
operative for pressing selectively said first elongated rod and
said second elongated rod inward of said first body portion and
second body portion respectively for opening said first valve
opening and second valve opening whereby gas flow from said inlet
orifice to said outlet orifice and said pilot outlet orifice.
18. A gas barbeque control system according to claim 15 including
thermoelectric transducers mounted on said barbeque and operative
for converting heat of said barbeque for operating electrical
components of said control system.
19. A gas barbeque control system according to claim 18 including a
light operative for illuminating the interior of said barbeque, and
an imaging device mounted on a side wall of said barbeque and
operative for generating an electronic image of said interior of
said barbeque and transmitting said image to a display device for
monitoring cooking condition of food in said interior.
Description
TECHNICAL FIELD
[0001] The invention relates to a remote control system for
igniting and controlling a plurality of operations of a gas burning
device such as a barbeque for example.
BACKGROUND OF THE ART
[0002] Gas burning devices such as barbeque devices are usually
convenient to use and are easy to maintain. However, users of gas
barbeque devices in particular have been fearful in igniting and
adjusting the operation of the gas burner in the device in use
because of the potential danger of gas accumulation and explosion
in such operation. Particularly, since the user must stand
immediately close to the device to perform the igniting operation
usually with a match or lighter, and repeated failure to ignite the
device, such as in a windy condition, would result in leakage of
gas into the area around the device that could result in a gas
explosion, and a gas explosion until such circumstances could cause
fatal harm to the user. In areas of cold climate it is also very
uncomfortable to ignite a barbeque device outdoors. Remote
controlled syrods have been developed for igniting a gas barbeque
device without the user situated immediate adjacent to the device.
However, they do not address all the requirements of the users such
as the capability of controlling the operation of the device after
it has been ignited.
[0003] To reduce the difficulties associated with manually ignited
gas burning devices, it is advantageous to produce a remote control
system for igniting on a pilot on demand basis and controlling a
plurality of operations of a barbeque device during use. A
desirable remote control system may be operative for monitoring the
temperature and condition of the food being cooked in the barbeque.
To reduce energy requirements and need for battery replacements a
thermoelectric generating system may be desired for operating
various components
[0004] Objects of the invention will be apparent from review of the
disclosure, drawings and description of the invention below.
DISCLOSURE OF THE INVENTION
[0005] The invention provides a gas control system having: a valve
body having a preliminary chamber, an inlet orifice in
communication with said preliminary chamber, an outlet orifice on
said valve body in communication with a gas burning device, a main
chamber within said valve body, said main chamber and said
preliminary chamber communicating through a valve opening, a
stopper in said preliminary chamber and normally urged by a
compression spring located in said preliminary chamber to engage
with said valve opening to close communication between said
preliminary chamber and said main chamber, an elongated slidable
rod slidably mounted in said valve body and having an inner end
portion juxtaposed with said stopper washer, and a pressing arm
juxtaposed with another end of said slidable rod and operative for
pressing said slidable arm inwards to disengage said stopper washer
from said valve opening for releasing the gas in said preliminary
chamber into said outlet orifice.
DESCRIPTION OF THE DRAWINGS
[0006] In order that the invention may be readily understood,
embodiments of the invention are illustrated by way of example in
the accompanying drawings.
[0007] FIG. 1 is a sectional view of the control valve for
controlling the flow of gas to the burner and the pilot on demand
arrangement in a first embodiment of the system of the present
invention.
[0008] FIG. 2 is a perspective top elevation of the gas barbeque
device provided with the control valve of the remote control system
of the present invention.
[0009] FIG. 3 is a schematic block diagram showing the remote
control system of the present invention.
[0010] FIG. 4 is a schematic block diagram showing the two way
communication between the remote control and the barbeque device in
the remote control system of the present invention.
[0011] FIG. 5A is a perspective top rear elevation view of the
barbeque unit provided with a plurality of thermoelectric
generating modules for providing operating electrical power to
components of the present system.
[0012] FIG. 5B is an enlarged view of the thermoelectric generating
module of FIG. 5A.
[0013] FIG. 6 is a top view of the barbeque device with open lid
showing the provision of video components for monitoring the
condition of the food being cooked in the barbeque device.
[0014] FIG. 7 is a sectional view of a gas valve according to a
second embodiment of the invention for controlling the gas supplied
to the barbeque device.
[0015] FIG. 8 is a sectional view of a third embodiments of a gas
valve having a counterbalance lever arrangement for controlling the
gas supplied to the barbeque device.
[0016] FIG. 9 is a sectional view of an electromagnetic drive for
the gas valve of FIG. 8.
[0017] FIG. 10 is a sectional view of an electromagnetic drive for
the syrod of the present invention.
[0018] Further details of the invention and its advantages will be
apparent from the detailed description included below.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0019] With reference to FIG. 1, a first embodiment of the
invention includes a gas control valve 10 for the remote control
system of the present invention has a main body 11 which has a gas
inlet orifice 12 for admitting the incoming gas into a preliminary
chamber 13. The inlet orifice 12 is normally closed by a plunger 14
operated by an electromagnetic control safety device 15 and a
biasing spring 16. The plunger 14 has a rubber washer 17 which is
normally maintained engaged with the admitting opening 18 by the
biasing spring 16 to prevent the incoming gas from passing through
the admitting opening 18 to the pilot orifice 19 and the main
chamber 20. A top body 21 is mounted to the main body 11 by bolts
22 and 23 and a circular washer 24 together with O-ring 25 seal the
joint between the two bodies. An elongated rod 26 is slidably
mounted within the top body 21. A bushing 27 is mounted at the
inner portion of the rod 26 located within the main chamber 20. The
bushing 27 is retained in place by a retaining ring 28 and a rubber
washer 29 fixedly mounted on the rod 26. An O-ring 30 is located
between the rubber washer 29 and the bushing 27. Another washer 31
is mounted on the rod 26 and located adjacent to the circular
washer 24. The washer 31 is retained in place by a retaining ring
32. A compression spring 33 is located between the rubber washer 29
and the washer 31 to maintain the bushing 27 firmly pressing
against the retaining ring 28. A rubber washer 34 is mounted on the
bushing 27 on the side facing the main opening 35 leading into the
main chamber 20. An O-ring 36 is provided between the circular
washer 24 and the top body 21 to prevent any leakage of gas between
the slidable rod 26 and the top body 21. The middle portion of the
slidable rod 26 is located in an inner chamber 37. A washer 38 is
mounted on the slidable rod 26 adjacent to a front opening 39 of
the inner chamber 37, and retaining ring 40 maintains the washer 38
fixedly mounted in place on the slidable rod 26. A compression
spring 41 is located in the inner chamber 37 and extends between
the rear wall 42 of the inner chamber 37 and the washer 38. The
spring force of the compression spring 41 cooperating with the
washer 38 to maintain the slidable rod 26 normally in the position
with its front end portion 43 extending outside the front opening
39 as best shown in FIG. 1. An angle support 44 is mounted to the
front side of the top body 21 by bolts 45 and 46. The front end
portion 43 of the slidably rod 26 extends outwards of an opening 47
of the angle support 44. A drive motor 48 preferably having a high
step down gear ratio as shown in a dotted circular line in FIG. 1
is mounted on the perpendicular plate 49 of the angle support 44 by
screws 50 and 51. The drive shaft 52 of the motor 48 extends
outwards of the perpendicular plate 49, and a pivotal arm 53 is
mounted to the drive shaft 52 by a set screw 54. The side of the
pivotal arm 53 is juxtaposed to the front end 55 of the slidable
rod 26 so that the pivotal arm 53 is pivotable to push the slidable
rod 26 to move inwards of the gas control valve 10.
[0020] As shown in FIG. 2, the gas control valve 10 is connected
between the gas supply such as the natural gas supply or a portable
propane gas tank 56 and the barbeque unit 57. For simplicity of
illustration, a propane gas tank is shown. In the well known
manner, a gas regulator 58 is provided between the gas supply and
the barbeque unit when a propane gas tank is used. The gas supply
line 59 connects between the gas regulator 58 and the inlet orifice
12 of the gas control valve 10. An elongated pilot gas tube 60 is
connected to the pilot orifice 19 of the gas control valve 10. The
pilot gas tube 60 extends into the barbeque unit 57 and it is
provided with pilot openings 61 and 62 located closely adjacent to
the gas burners 63 and 64. Only one pilot opening may be provided
if the barbeque unit has only one gas burner. Two burners are shown
as an example. The end 65 of the pilot tube 60 may also extend to
locate adjacent to a side burner 66 if such side burner is provided
on the barbeque unit, and a pilot opening 67 is provided at the end
portion of the pilot tube 60. A main gas line 68 is connected
between the output orifice 69 of the gas control valve 10 and the
gas burners 63 and 64 and the side burner 66. Pilot flame igniters
70, 71 and 72 are located adjacent to the pilot openings 61, 62 and
67 respectively. The pilot flame igniters 70, 71 and 72 are
operated by a sparker module 73 mounted on the barbeque unit 57.
The barbeque unit 57 may be provided with manually adjustable gas
control valve 74, 75 and 76 for manual adjustment of the burner
flame in the well known manner. The two burner and one side burner
barbeque unit is shown as an example for illustrating the present
invention. The system may be adapted for use with barbeque units
have only one burner or a plurality of burners and with or without
a side burner by the appropriate elimination or addition of
components.
[0021] In operation, the gas control valve 10 is operated by
actuating the motor 48 is so that the pivotal arm 53 is pivoted in
a clockwise direction to push the slidable rod 26 to move inwards
of the valve 10 until the rear end 56 of the slidable rod 26 pushes
the rubber washer 17 of the plunger 14 to disengage from the
admitting opening 18 while the rubber washer 34 of the bushing 27
is pressed tightly against the opening 35 to seal the communication
between the preliminary chamber 12 and the main chamber 20 so that
in the incoming gas flows into the pilot orifice 19 through the
admitting opening 18 to the pilot tube 60. The igniters 70, 71 and
72 are actuated by the sparker module 73 to provide the spark for
igniting the gas emitting from the pilot openings 61, 62 and 67 to
provide the pilot flames 77, 78 and 79 adjacent to the gas burners
63, 64 and 66 respectively. After the pilot flames 77, 78 and 79
have been ignited, the heat of the pilot flame 77 is detected by a
thermoelectric converter 80 to provide an electric current which is
conducted by lead wires 81 connected to the electromagnetic control
safety device 15 to operate the latter so as to hold the plunger 14
down in order for the gas to continue flowing to the pilot orifice
19. The motor 41 is then operated in the reverse direction so as to
pivot the pivotal arm 53 in the counterclockwise direction to allow
the slidable rod 26 to move outwards by the spring force of the
compression springs 33 and 41. The washer 34 of the bushing 27 is
then engaged from the main opening 35 so that incoming gas flows
into the main chamber 20 to exit through the outlet orifice 69. The
incoming gas continues to flow to the pilot tube 60 through the
pilot orifice 19 since the plunger 14 is now held down by the
electromagnet control safety device 15. The gas emitting from the
gas burners 63, 64 and 66 are then ignited by the pilot flames 77,
78 and 79 respectively. After the burners 63, 64 and 66 have been
ignited, the motor 48 may be operated to move the slidable rod 26
in or out in selective degree so as to modulate the amount of gas
flowing to the burners 63, 64 and 66 for adjusting the size of the
flame of the burners to select the desirable cooking requirement.
The motor 48 of the gas control valve 10 operate through the above
three time period sequence including starting the barbeque unit
until controlling the required cooking conditions during
cooking.
[0022] As shown in FIG. 3, the electronic system for operating the
gas control valve 10 is, for example, a CMOS logic circuit system.
A low battery inhibitor device 82 is provided in the system to
ensure that the sequence to start the motor 48 of the gas control
valve 10 is not initiated if there is insufficient power for the
motor to proceed with the entire sequence of operation as described
above. The operation is initiated by actuating an ON signal
generator 83 which provides a pulse signal through a gate circuit
84 to the flip-flop circuit 85 to initiate a blocking timer 86 to
operate the motor 48 through the above three-period sequence as
represented by timing blocks 87, 88 and 89. In the time period T1
as indicated in timing block 87, a forward signal is sent from a
forward signal generator as represented pictorial by the block 90
to drive the motor 48 clockwise as pictorial represented by the
block 91 so that the pivotal arm 53 pushes the slidable rod 26 of
the gas control valve 10 inwards to permit the incoming gas to flow
to the pilot orifice 19. It would also provide the sufficient time
period to ensure that the electromagnetic safety device 15 is
actuated to hold the plunger 14 in place for the gas to flow from
the pilot orifice 19 to the pilot tube 60. The second time period
T2 as pictorial represented by block 88 commences when the gas
flows to the pilot tube 60. In the time period T2, the motor is not
operated while the sparker module 73 is operated by actuating a
sparker relay 92 to ignite the igniters 70, 71 and 72 so as to
create the pilot flames 77, 78 and 79 from the gas emitting from
the pilot openings 61, 62 and 67. After the pilot flame 77 is
ignited, the flame actuates the thermoelectric converter 80 to
provide the electric power to maintain the plunger 14 down so that
gas continues to flow to the pilot tube 60. The time period T3 as
represented pictorial by block 89 commences at the termination of
time period T2. In the time period T3, the motor 48 is first
operated by a reverse signal generated by a reverse signal
generator as pictorial represented by reverse block 93 sent to the
motor drive 91 to pivot the pivotal arm 53 counterclockwise so that
the slidable rod 26 is returned to the position to allow gas to
flow through the gas line 68 to the burners 63, 64 and 66. The gas
emitting from the burners 63, 64 and 66 is ignited by the pilot
flames 77, 78 and 79 thus completing the sequence for igniting the
barbeque unit 57.
[0023] After the barbeque unit 57 has been ignited, the condition
of the flame of the burners 63, 64 and 66 may be controlled by
actuated a flip-flop circuit 94. The flip-flop circuit 94 is
actuated by operating a down signal generator 95 which provides a
signal to the forward signal generator 90 to rotate the motor 48 in
the clockwise direction over a short time period T4 as represented
by block 96. Thus, the valve 10 may be adjusted in small
incremental steps to reduce the size of the flame of the burners
each time the down signal generator 95 is actuated. Similarly, an
up signal generator 97 to provide a signal to the reverse signal
generator 93 to rotate the motor 48 in the counterclockwise
direction over a short time period T5 as represented by block 98.
Thus, the valve 10 is adjusted in small incremental steps to
increase the size of the flame of the burner flames each time the
up signal generator 97 is actuated. The timing of the up and down
signal pulses are such that a larger time is allowed when the motor
48, and in turn the slidable rod 26, is operated against the spring
force whereas a smaller time pulse is allowed to drive the motor 48
when the latter is cooperated with the spring force to move the
slidable rod 26 outwards, which may be a rod secured on a cap
attached to cover the front end 55 passing through arm 53 with a
button on the end for depressing.
[0024] An override bar 99 is mounted on the front end portion 43,
as best shown in FIG. 1, such that the slidable rod 26 may be
operated manually by pushing or pulling this override bar.
[0025] To turn the barbeque unit 57 off, an Off signal generator
100 is operated to provide an off signal to the flip-flop circuit
85 to enable a close relay 101 which is in series with the
thermoelectric converter 80 and the electromagnetic safety device
15. The close relay 101 is momentarily energized so that the
thermocouple switch 102 of the thermoelectric converter 80 is open
thus turning off the operating power to the electromagnetic safety
device 15 to release the plunger 14. The valve 10 will then return
to the normal condition with the admitting opening 18 closed by the
rubber washer 17 to shut off the gas flow to both the pilot orifice
19 and the outlet orifice 69. A manual switch 103 in series with
the thermocouple switch 102 may be provided so that the barbeque
unit 57 may be conveniently and alternatively turned off by
operating this manual switch 103 to shut off the valve 10.
[0026] The gas control valve 10 may be operated with a remote
control system as shown in FIG. 4. The remote control system
consists of a sensing and control unit 104 and a selection unit
105. The sensing and control unit 104 may be mounted at a strategic
location in the barbeque unit for sensing the temperature of the
barbeque unit or the food selectively. The temperature of the
barbeque unit or the food is detected by a temperature sensor 106
of the sensing and control unit 104. The detected temperature level
is converted into a digital or analog signal by a coder 107, which
is transmitted via an RF transmitter 108 and channelled through a
T/R switch 109. The selection unit 105 receives the temperature
level signal via a T/R switch 110. The signal is amplified by an
amplifier 111 and decoded by a decoder 112 so that the detected
temperature level is shown by a display 113. When the user, after
observing the temperature level displayed, may select or alter the
temperature to a desirable level by actuating a set temp unit 114
in the selection unit 105. The signal of the set temp unit 114 is
compared with the detected temperature level signal from the
decoder 112 by a comparator 115 and the resulting temperature level
differential is converted to the digital or analog temperature
selection coded signal by a coder 116. The temperature selection
coded signal is transmitted by transmitter 117 via the T/R switch
110. When the temperature selection coded signal is received by the
T/R switch 109 of the sensing and control unit 104 it is amplified
by an amplifier 118 and is decoded by a decoder 119. The decoded
signal is compared with the temperature level signal from the
temperature sensor 106 by a comparator 120 and the resulting
differential signal is applied to the motor 48 to operate the motor
in a clockwise or counterclockwise direction for adjusting the
flame level of the barbeque burners accordingly.
[0027] The electrical power required for operating the sensing and
control unit 104 and the gas control valve 10 may be provided by a
plurality of thermoelectric generator modules mounted on the
barbeque unit. As best shown in FIG. 5A, for example, three
thermoelectric generator modules 121, 122 and 123. As best shown in
the isolated enlarged top elevation view of FIG. 5B, each
thermoelectric generator module has a heat sink 124 having a
plurality of spaced parallel fins 125 and a plurality of
transducers 126 mounted on the surface opposite to the fins 125.
Each thermoelectric generator module 121-123 is mounted to the rear
wall 127 of the barbeque unit by bolts 128 and 129 with the
transducer therein contacting the barbeque rear wall 127. The bolts
128 and 129 are insulated by ceramic washers 130 and 131. The
thermoelectric generator modules 121, 122 and 123 are positioned
such that the fins 125 are extending vertically to facilitate the
heat emitting by convection from the barbeque unit rear wall 127 or
some other convenient location on the barbeque to flow through the
vertical spacing between the fins 125. The transducers 126 are
connected in series to provide a voltage level sufficient to
operate various electrical components of the system of the present
invention. Also, thermopiles may be used as transducers 126 to
generate the electrical power with a large voltage level.
[0028] A visual monitoring system as shown in FIG. 6 may be
incorporated for viewing and monitoring the condition of the food
inside the barbeque during operation. An observation window 132 is
formed at the rear wall 127 of the barbeque unit. A light 133 is
provided to illuminated the interior of the barbeque unit. A tube
134 is mounted over the observation window and extending outwards
rearwardly from the rear wall 127. The view within the barbeque
unit as illuminated by the light 133 is enlarged by a lens 135 to
provide an image detected by an image sensor 136 such as a CCD
device mounted at the rear end of the tube 133. The image may be
retrieved by a remote-controlled video camera and transmitter 137
to a video display.
[0029] A simplified gas control valve 138 may be used with a
pilot-on-demand barbeque unit. The valve 138 has a gas inlet
orifice 139 and a single outlet orifice 140 which provides the gas
to both the pilot tube and the burner tube as described above. The
valve 138 has a main chamber 141 and a preliminary chamber 142
separated by an opening 143. The preliminary chamber 142 is
enclosed by a panel 144 mounted to the valve by bolts 145 and 146.
An O-ring 147 is provided between the valve body and the panel 144
to prevent any gas leakage from the valve 138 through the
preliminary chamber 142. The inlet orifice 139 communicates with
the preliminary chamber 142 and the outlet orifice 140 communicates
with the main chamber 141. A T-shaped plunger 147A is located in
the preliminary chamber 142. A rubber washer 148 is mounted on the
plunger 147A, and the plunger 147A is normally biased by the spring
force of a compression spring 149 in the preliminary chamber 142 to
press the rubber washer 148 against the opening 143. Thus, the
compression spring 149 maintains the opening 143 closed by the
rubber washer 148 of the plunger 147A so that gas incoming to the
preliminary chamber 142 can not flow through the opening 143 into
the main chamber 141. A slidable rod 150 is slidably mounted in the
valve 138 and it is largely located in the main chamber 141 with
its rear end 151 juxtaposed to the rubber washer 148 of the plunger
147A and its front end portion 152 extending outwards from the top
body 153 of the valve 138. Similar to the gas control valve 10
described above, a motor 48 is mounted on an angle support 44 which
attached to the top body 153 by bolts 154 and 155. The pivotal arm
53 is in contact with the front end 156 of the pivotal arm 53 so
that operation of the motor 48 will cause the slidably rod 150 to
move inwards to disengage the rubber washer 148 from the opening
143 so as to allow incoming gas in the preliminary chamber 142 to
flow to the outlet orifice 140 through the main chamber 141.
O-rings 157 and 158 are provided between the slidable rod 150 and
the top body 153 to prevent gas leakage from the main chamber 141.
The valve 138 operates closely similar to the gas control valve 10
with the operation of the motor 48 as described above.
[0030] Another alternative embodiment of the gas control valve is
shown in FIG. 8, which is a combination of valve 10 and valve 138
described above. This combination valve 159 has two slidable rods
160 and 161. The slidable rod 160 is provided in the right portion
162 having a construction similar to valve 10 and a left portion
163 similar in construction to valve 138. The right portion 162
controls the gas flowing to the pilot orifice 164 and the left
portion 163 controls the gas flowing to the main gas outlet orifice
165. The slidable rods 160 and 161 are operated by a single motor
166 with a seesaw bar 167 mounted to the motor shaft. One end
portion of the seesaw bar 167 is juxtaposed to the outer end of the
slidable rod 160 while the other end portion of the seesaw bar 167
is juxtaposed to the outer end of the slidable rod 161. Gas is
admitted into the preliminary chamber 168 through the inlet orifice
169. The motor 166 is first operated to rotate in a clockwise
manner for pushing the slidable rod 160 inwards so that the rubber
washer 170 mounted at the rear end of the slidable rod 160 is
disengaged from the opening 171 to facilitate the gas to flow to
the pilot orifice 164 through the main chamber 172. At this stage,
the opening 173 between the main chamber 172 and the outlet chamber
174 is closed by the rubber washer 175 mounted on the slidable rod
161 so that no gas is flowing from the main chamber 172 to the
outlet chamber 174. The pilot flame is ignited when the gas is
flowing out of the pilot orifice 164 as described previously. The
pilot flame then generates an electrical voltage to energize the
electromagnetic safety device 176 to maintain the slidable rod 160
in the inward position and the opening 171 remaining open for gas
to continue flowing out of the pilot orifice 164. The motor 166 is
then operated to rotate in a counterclockwise direction so that the
other end portion of the seesaw bar 167 presses the slidable rod
161 inwards to disengage the rubber washer 175 from the opening 173
so that gas will flow from the main chamber 172 to the outlet
chamber 174 and will exit from the outlet orifice 165 to the
burners to be ignited by the pilot flame. At this stage, the
slidable rod 160 is still maintained in the inward position by the
electromagnetic safety device 176 so that gas continues to flow out
of both the pilot orifice 164 and the outlet orifice 165. The valve
159 is turned off by de-energizing the electromagnetic safety
device 176 so that the compression spring 177 returns the rubber
washer 170 to the position pressing against the opening 171 and the
compression spring 178 returns the rubber washer 175 to the
position pressing against the opening 173, therefore, gas is
prevented from flowing into the main chamber 172 and the outlet
chamber 174. The advantages of this embodiment are that the force
exerted on the seesaw bar 167 is counterbalanced and the distance
for moving the slidable rods 160 and 161 is much smaller.
[0031] As best shown in FIG. 9 the seesaw bar 167 of the valve 159
may be operated by an electromagnet assembly 179 with seesaw bar
167 mounted in a pivotable manner to a supporting post 180. The
electromagnet assembly 179 has an electromagnetic winding 181 wound
on a mild steel core 182. A solenoid plunger 183 is slidably
mounted within the core 182. The solenoid plunger 183 has a mild
steel portion 184 surrounded by the electromagnetic winding 181 and
a non-magnetic plunger arm 185 extending outwards to contact the
seesaw bar 167. The electromagnet assembly 179 may be operated to
pivot the seesaw bar 167 in a manner similar to that operated by
the motor 166.
[0032] An electromagnetic device 186 as shown in FIG. 10 may be
incorporated in the gas control valve 10 for operating the slidable
rod 26 in an overriding manner. The electromagnetic device 186 has
a electromagnetic winding 187 wound on a bobbin 188 located within
a mild steel enclosure 189. A mild steel plunger 190 is slidably
mounted within the electromagnetic device 186 and it is operative
to move in a back and forth sliding movement by energizing the
electromagnetic winding 187. The plunger 190 has an arm 191
extending outward of the enclosure 189. The electromagnetic device
186 is mounted on the angle support 44 with the outer end portion
of the slidable rod 26 slidably extending within the
electromagnetic device 186 to engage with the plunger 190. Thus,
the operation of the plunger 190 in the back and forth sliding
movement will cause the slidable rod 26 to move in the similar
manner to provide the functions of the valve 10 as described above.
The arm 191 may also be operated manually to move the slidable rod
26 to provide the various functions.
[0033] The valve 10 can be disabled easily using a permanent magnet
applied externally adjacent the electromagnetic control device 15
to hold the plunger 14 in an open position. Further modification of
the system can include use of multiple pilot lights 77 with
multiple thermocouples 80 to light multiple burners 63, 64 (as
shown in FIG. 2) where the pilot lights 77 are supplied from a
common gas manifold.
[0034] Although the above description relates to a specific
preferred embodiment as presently contemplated by the inventor, it
will be understood that the invention in its broad aspect includes
mechanical and functional equivalents of the elements described
herein.
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