Gas burner system for a gas cooking hob

Abstract

The present invention relates to a gas burner system ( 10 ) for a gas cooking hob, in particular for a domestic gas cooking hob. Said gas burner system ( 10 ) comprises a gas burner assembly ( 12 ) including a plurality of flame ports. At least one pot support ( 14 ) is arranged above and/or around the gas burner assembly ( 12 ) and defining a distance between said gas burner assembly ( 12 ) and a bottom of a cooking pot. At least one supply air fan ( 16 ) is provided for generating an air flow ( 24 ) to the gas burner assembly ( 12 ). A gas inlet ( 38 ) is connectable or connected to a gas supply. A gas regulator ( 18; 30; 36; 38 ) is provided for regulating a gas flow from the gas inlet ( 38 ) to the gas burner assembly ( 12 ). A control unit ( 20 ) is provided for controlling the supply air fan ( 16 ) and the gas regulator ( 18; 30; 36; 38 ). At least one thermocouple ( 22 ) is provided for detecting flames above the gas burner assembly ( 12 ) and for providing a flame signal ( 28 ) to the control unit ( 20 ).

1 . A gas burner system for a gas cooking hob, which gas burner system comprises:
 a gas burner assembly including a plurality of flame ports,   at least one pot support arranged above and/or around the gas burner assembly and defining a distance between said gas burner assembly and a bottom of a cooking pot when said pot is supported on said pot support,   at least one supply air fan for generating an air flow to the gas burner assembly,   a gas inlet connectable or connected to a gas supply,   a gas regulator for regulating a gas flow from the gas inlet to the gas burner assembly,   a control unit for controlling the supply air fan and the gas regulator, and   at least one thermocouple for detecting flames above the gas burner assembly and for providing a flame signal to the control unit.   
     
     
         2 . The gas burner system according to  claim 1 , wherein the supply air fan is provided for switching off the gas burner assembly by making the flames lift and/or moving the flames aside, so that the thermocouple does not detect the flames above the gas burner assembly anymore and an appropriate flame signal is sent to the control unit. 
     
     
         3 . The gas burner system according to  claim 1 , wherein the gas regulator comprises a gas tap interconnected between the gas inlet and the gas burner assembly, wherein said gas tap is closed by the control unit if the thermocouple detects no flames above the gas burner assembly. 
     
     
         4 . The gas burner system according to  claim 1 , wherein the gas burner system is provided for an automatic cooking process, wherein the gas burner assembly is switched off after a predetermined time. 
     
     
         5 . The gas burner system according to  claim 1 , further comprising at least one pot sensor for detecting a presence of said cooking pot on the pot support, wherein said pot sensor provides the control unit with a pot signal, and wherein the gas burner assembly is switched off if no cooking pot is detected on the pot support. 
     
     
         6 . The gas burner system according to  claim 1 , further comprising means for detecting and/or estimating a pressure (Pa) and/or a temperature (Ta) of the air flow. 
     
     
         7 . The gas burner system according to  claim 1 , further comprising means for detecting and/or estimating a pressure (Pg), a temperature (Tg) and/or a flow rate (Φg) of the gas flow. 
     
     
         8 . The gas burner system according to  claim 1 , further comprising a mixer unit for receiving the air flow from the supply air fan and the gas flow from the gas inlet, wherein said mixer unit generates an air-gas mixture and provides the gas burner assembly with said air-gas mixture. 
     
     
         9 . The gas burner system according to  claim 1 , wherein the air flow from the supply air fan depends on the gas flow from the gas inlet, wherein said gas flow is adjusted or adjustable by a user, and wherein the gas flow is read or estimated on the basis of a knob for adjusting the gas flow, by a gas flow sensor or by an electronic gas valve actuator. 
     
     
         10 . The gas burner system according to  claim 8 , further comprising a gas dosing valve interconnected between the gas inlet and the mixer unit. 
     
     
         11 . The gas burner system according to  claim 1 , wherein the gas flow from the gas inlet depends on the air flow from the supply air fan, wherein said air flow is adjusted or adjustable by the user and read by the means for detecting and/or estimating a pressure (Pa) and/or a temperature (Ta) of the air flow, and wherein the gas flow is automatically adjusted by the gas dosing valve. 
     
     
         12 . The gas burner system according to  claim 10 , wherein the gas flow adjusted by the gas dosing valve is proportional to the air flow from the supply air fan. 
     
     
         13 . The gas burner system according to  claim 1 , further comprising a Venturi system for receiving the air flow from the supply air fan and the gas flow from the gas inlet, wherein said Venturi system generates an air-gas mixture and provides the gas burner assembly with said air-gas mixture. 
     
     
         14 . The gas burner system according to  claim 1 , wherein air is provided by a pressurized gas tank or a further fan, wherein said pressurized gas tank or further fan, respectively, is integrated in a closed loop and keeps a pressure in a lower box of the Venturi system at a constant value. 
     
     
         15 . A gas cooking hob comprising the burner system according to  claim 1 . 
     
     
         16 . A gas cooking hob comprising:
 a gas burner having a plurality of flame ports;   a pot support for supporting a pot at a distance above said flame ports of said gas burner;   a supply air fan beneath said gas burner for generating an air flow toward the gas burner;   a gas regulator for controlling a gas flow from a gas inlet to said gas burner;   a thermocouple configured to detect flames emitted from said flame ports;   a mixer unit configured to receive said gas flow from said gas regulator and at least a portion of said air flow from said supply air fan, and to deliver an air-gas mixture to said burner in order to yield said flames emitted from said flame ports;   a controller operatively coupled to said thermocouple for receiving a flame signal therefrom indicative of the presence of said flames, to said supply air fan for controlling said air flow, and to said gas regulator for controlling said gas flow;   said controller being adapted to operate said supply air fan in response to at least one of an automatic cooking program, detection that no pot is resting on said pot support, or a user input, in order to increase said air flow sufficiently to deflect said flames so that said flames are no longer detected by said thermouple resulting in said flame signal indicating an absence of said flames,   wherein in response to said flame signal indicating said absence of said flames said controller actuates said gas regulator to turn off said gas flow from said gas inlet.   
     
     
         17 . The gas cooking hob according to  claim 16 , said gas regulator comprising one of a mechanical gas tap, a gas dosing valve or a gas flow controller. 
     
     
         18 . The gas cooking hob according to  claim 16 , said mixing chamber comprising a Venturi system, wherein a portion of said air flow is directed to said Venturi system in order to mix therein with gas from said gas flow in order to supply said air-gas mixture from said Venturi system to said burner, and a remainder of said air flow is directed directly to said gas burner from said supply air fan. 
     
     
         19 . The gas cooking hob according to  claim 16 , said controller further being adapted so that during a warm-up phase when said flame signal indicates a relatively cold temperature below a predetermined first temperature threshold, the controller controls said supply air fan to deliver said air flow at a first rate, and then after at least one of said flame signal indicating a temperature above a second predetermined temperature threshold greater than said first temperature threshold, or elapsing of a predetermined period of time, the controller controls said air supply fan to deliver said air flow at a second rate lower than said first rate. 
     
     
         20 . The gas burner system according to  claim 16 , said controller further being adapted to operate said supply air fan to control a rate of said air flow based on a user-adjustable rate of said gas flow from the gas inlet.