Barbecue grill with fire retarding means

An improved barbecue grill of the type, in which a kettle having an upper rim defining an opening is arranged and adapted to hold cooking fuel which may be ignited in the bottom hollow thereof to produce a flame, and in which said kettle further has a grill for supporting food in a generally horizontal plane located in proximity to said upper rim and above the cooking fuel, wherein the improvement comprises a means for retarding excessive flame which may be produced during the cooking process comprising:

• a. a means for distributing a fluid fire suppressant having at least one discharge nozzle accessible to and directed generally toward the flame in said kettle,
• said means for distributing a fluid fire suppressant further comprises a reservoir for storing the fluid fire suppressant and an electrically powered pump;
• b. a means for sensing light being optically accessible to and operably responsive to the light from an excessive flame produced during the cooking process and operably connected to a means for activating,
• said means for sensing light comprises a circuit operable to sense the existence of an excessive flame condition to turn on a pump providing a spray of fluid fire retardant to douse the flame wherein:
• said circuit comprises a battery-operated power supply circuit having a six volt battery connected across terminals and an on/off switch connected in series with a filtering capacitor across the terminals to develop six volt power for supplying the remainder of the circuit,
• said circuit further comprises a photodetector having an emitter connected to ground and a collector connected via a first resistor to the power supply circuit,
• said photodetector having a transistor output that is switched on in response to sensed light being above a select level,
• said collector of the photodetector is connected to the base of a PNP transistor having its collector connected to supply and its emitter connected via a second resistor to ground and via a third resistor to the base of a first NPN transistor, the emitter of which is connected to ground,
• said collector of the first NPN transistor is connected via a 1K resistor to supply and to a first junction which is connected via a parallel combination of a first diode and a fourth resistor to a second junction,
• said circuit further comprises a feedback resistor connected between the first junction and the base of the PNP transistor,
• the second junction is connected via a first capacitor to ground and to a first inverter, the output of which is connected through a second inverter, which is in turn connected to four parallel inverters acting as a buffer,
• said first and second inverters are used to square up the signal at the second junction,
• the output of the four parallel inverters is connected via a fifth resistor to the base of a second NPN transistor having its emitter connected to ground and its collector connected through a diode to a third junction which has a pump motor winding, a second capacitor and a second diode connected in parallel between said third junction and the supply,
• whereby, during a normal state, when no flame is being sensed, the photodetector is off so that the transistors are off, the pump motor winding is de-energized, and the supply is connected through the 1K resistor and the first diode to charge the first capacitor and with the second junction charged to the six volt supply level,
• whereby, during an excited state, when an excessive amount of light is detected by the photodetector, it turns on, thus turning on the PNP transistor to in turn turn on the first NPN transistor during which the first capacitor discharges through the fourth resistor and the first NPN transistor to ground, providing a time delay to prevent pump turn on in the event that only a momentary flame is sensed, and wherein as the voltage across the first capacitor drops, the output of the first inverter goes high, causing the output of the second inverter to go low, which in turn causes the output of the four parallel inverters to go high providing sufficient current for turning on and driving the second NPN transistor, whereby the pump is connected between supply and ground to energize the pump and thus commence a spray of fluid fire retardant,
• whereby, the second capacitor and the second diode act as a filter to stop inductive spikes and as a clamp to protect from positive voltage spikes with the diode protecting from reverse spikes, and
• whereby, after the spray of fluid fire retardant douses the flame, the photodetector is turned off so that once the first capacitor is charged through the 1K resistor to a sufficient level, the pump motor winding is de-energized and the circuit returns to normal state;
• c. the means for activating having a means for electrical power,
• said means for electrical power being operably connected to power the means for distributing a fluid fire suppressant and the means for sensing light, and
• whereby, an excessive flame produced during the cooking process that is sensed by the means for sensing light activates the means for distributing a fluid fire suppressant to discharge said fluid fire suppressant toward the excessive flame and thereby retard said excessive flame.

An improved barbecue grill of the type, in which a kettle having an upper rim defining an opening is arranged and adapted to hold cooking fuel which may be ignited in the bottom hollow thereof to produce a flame, and in which said kettle further has a grill for supporting food in a generally horizontal plane located in proximity to said upper rim and above the cooking fuel, wherein the improvement comprises a means for retarding excessive flame which may be produced during the cooking process comprising:

• a. a means for distributing a fluid fire suppressant having at least one discharge nozzle accessible to and directed generally toward the flame in said kettle,
• said means for distributing a fluid fire suppressant further comprises a horizontal distribution ring having a plurality of discharge nozzles;
• b. a means for maintaining a quantity of water in said horizontal distribution ring and wherein the horizontal distribution ring is disposed outside of the kettle;
• c. a means for sensing light being optically accessible to and operably responsive to the light from an excessive flame produced during the cooking process and operably connected to a means for activating;
• d. the means for activating having a means for electrical power,
• said means for electrical power being operably connected to power the means for distributing a fluid fire suppressant and the means for sensing light;
• and
• whereby, an excessive flame produced during the cooking process that is sensed by the means for sensing light activates the means for distributing a fluid fire suppressant to discharge said fluid fire suppressant toward the excessive flame and thereby retard said excessive flame.

An improved barbecue grill of the type, in which a kettle having an upper rim defining an opening is arranged and adapted to hold cooking fuel which may be ignited in the bottom hollow thereof to produce a flame, and in which said kettle further has a grill for supporting food in a generally horizontal plane located in proximity to said upper rim and above the cooking fuel, wherein the improvement comprises a means for retarding excessive flame which may be produced during the cooking process comprising:

• a. a means for distributing a fluid fire suppressant having at least one discharge nozzle accessible to and directed generally toward the flame in said kettle,
• said means for distributing a fluid fire suppressant further comprises a generally horizontal distribution member disposed outside of the kettle;
• b. a means for maintaining a quantity of water in said generally horizontal distribution member;
• c. a means for activating having a means for electrical power,
• said means for electrical power being operably connected to power the means for distributing a fluid fire suppressant;
• and
• whereby, the means for distributing a fluid fire suppressant to discharge said fluid fire suppresssant toward the flame and thereby retard the flame.

An improved barbecue grill of the type, in which a kettle having an upper rim defining an opening is arranged and adapted to hold cooking fuel which may be ignited in the bottom hollow thereof to produce a flame, and in which said kettle further having a grill for supporting food in a generally horizontal plane located in proximity to said upper rim and above the cooking fuel, wherein the improvement comprises a means for retarding excessive flame which may be produced during the cooking process comprising:

• a. a means for distributing a fluid fire suppressant having at least one discharge nozzle accessible to and directed generally toward the flame in said kettle,
• said means for distributing a fluid fire suppressant further comprises a generally horizontal distribution member disposed outside of the kettle;
• b. a means for sensing light being optically accessible to and operably responsive to the light from an excessive flame produced during the cooking process and operably connected to a means for activating;
• c. the means for activating having a means for electrical power,
• said means for electrical power being operably connected to power the means for distributing a fluid fire suppressant and the means for sensing light;
• and
• d. a means for maintaining a quantity of water in said generally horizontal distribution member,
• whereby, an excessive flame produced during the cooking process that is sensed by the means for sensing light activates the means for distributing a fluid fire suppressant to discharge said fluid fire suppressant toward the excessive flame and thereby retard said excessive flame.