Flame ionization detection for pan detection and power management in a gas cooktop

Abstract

A gas cooktop appliance includes a burner, a gas supply circuit in fluid communication with the burner, and a valve for controlling an amount of gas supplied to the burner from the gas supply circuit. An electrode is configured to provide an ignition spark and to obtain an ionization current. A control system is operably coupled with the valve and is configured to compare the ionization current to a setting of the valve and modify the amount of gas supplied to the burner when the difference between the ionization current and the setting of the valve is outside a predetermined threshold.

What is claimed is: 
     
         1 . A gas cooktop appliance comprising:
 a burner;   a gas supply circuit in fluid communication with the burner;   a valve for controlling an amount of gas supplied to the burner from the gas supply circuit;   an electrode configured to provide an ignition spark and to obtain an ionization current; and   a control system is operably coupled with the valve and the electrode, the control system is configured to:
 compare the ionization current to a setting of the valve; 
 detect if a difference between the ionization current and the setting of the valve is outside a predetermined threshold; and 
 modify the amount of gas supplied to the burner until the difference is within the predetermined threshold. 
   
     
     
         2 . The gas cooktop appliance of  claim 1 , wherein the ionization current is translated into an analog voltage by a translation module prior to being compared with the setting of the valve. 
     
     
         3 . The gas cooktop appliance of  claim 2 , wherein the control system is further configured to monitor the analog voltage and compare the analog voltage to a predictive model stored in a memory of the control system to determine a presence of a cooking vessel on the burner. 
     
     
         4 . The gas cooktop appliance of  claim 3 , wherein the control system is further configured to, upon determining an absence of the cooking vessel for a first predetermined amount of time, reduce the setting of the valve. 
     
     
         5 . The gas cooktop appliance of  claim 4 , wherein after the first predetermined amount of time, the setting of the valve is reduced to off. 
     
     
         6 . The gas cooktop appliance of  claim 4 , wherein after the first predetermined amount of time, the setting of the valve is reduced to a lower, non-zero setting. 
     
     
         7 . The gas cooktop appliance of  claim 6 , wherein after a second predetermined amount of time that is greater than the first predetermined amount of time, the setting of the valve is turned to off. 
     
     
         8 . The gas cooktop appliance of  claim 3 , wherein the control system is further configured to, upon determining an absence of the cooking vessel for a first predetermined amount of time, generate a notification to a user. 
     
     
         9 . The gas cooktop appliance of  claim 2 , wherein the control system includes a memory and a processor, the memory including instructions that cause the processor to compare the analog voltage to a temperature profile of the setting of the valve. 
     
     
         10 . A gas cooktop appliance comprising:
 a burner;   a gas supply circuit in fluid communication with the burner;   a valve for controlling an amount of gas supplied to the burner from the gas supply circuit;   an electrode configured to provide an ignition spark and to obtain an ionization current;   a translation module configured to translate the ionization current to an analog voltage; and   a control system is operably coupled with the valve and the translation module, the control system is configured to:
 compare the analog voltage to a setting of the valve; 
 detect if a difference between the analog voltage and the setting of the valve is outside a predetermined threshold; and 
 modify the amount of gas supplied to the burner until the difference is within the predetermined threshold. 
   
     
     
         11 . The gas cooktop appliance of  claim 10 , wherein the translation module includes a current-to-voltage converter circuit. 
     
     
         12 . The gas cooktop appliance of  claim 10 , wherein the control system is further configured to monitor the analog voltage and compare the analog voltage to a predictive model stored in a memory of the control system to determine a presence of a cooking vessel on the burner. 
     
     
         13 . The gas cooktop appliance of  claim 12 , wherein the control system is further configured to, upon determining an absence of the cooking vessel for a first predetermined amount of time, reduce the setting of the valve. 
     
     
         14 . The gas cooktop appliance of  claim 13 , wherein after the first predetermined amount of time, the setting of the valve is reduced to a lower, non-zero setting. 
     
     
         15 . The gas cooktop appliance of  claim 14 , wherein after a second predetermined amount of time that is greater than the first predetermined amount of time, the setting of the valve is turned to off. 
     
     
         16 . The gas cooktop appliance of  claim 12 , wherein the control system is further configured to, upon determining an absence of the cooking vessel for a first predetermined amount of time, generate a notification to a user. 
     
     
         17 . The gas cooktop appliance of  claim 16 , wherein the control system is further configured to generate the notification to a user audibly. 
     
     
         18 . A gas cooktop appliance comprising:
 a burner;   a gas supply circuit in fluid communication with the burner;   a valve for controlling an amount of gas supplied to the burner from the gas supply circuit;   an electrode configured to provide an ignition spark and to obtain an ionization current; and   a control system is operably coupled with the valve and the electrode, the control system is configured to:
 to monitor the ionization current and compare the ionization current to a predictive model stored in a memory of the control system to determine a presence of a cooking vessel on the burner; and 
 upon determining an absence of the cooking vessel for a first predetermined amount of time, generate a signal to reduce the setting of the valve. 
   
     
     
         19 . The gas cooktop appliance of  claim 18 , wherein the signal includes an alert for a user to manually reduce the setting of the valve. 
     
     
         20 . The gas cooktop appliance of  claim 18 , wherein the signal is transmitted to the valve to automatically reduce the setting of the valve.