Patent Publication Number: US-11041620-B2

Title: Boosted gas burner assembly with temperature compensation and low pressure cut-off

Description:
FIELD OF THE INVENTION 
     The present subject matter relates generally to gas burners, and more particularly to forced air gas burners for providing a constant flow of boost air. 
     BACKGROUND OF THE INVENTION 
     Conventional gas cooking appliances have one or more gas burners, e.g., positioned at a cooktop surface for use in heating or cooking an object, such as a cooking utensil and its contents. These gas burners typically combust a mixture of gaseous fuel and air to generate heat for cooking. Known burners frequently include an orifice, a Venturi mixing throat, and a plurality of flame ports. The orifice ejects a jet of gaseous fuel which entrains air while passing into the Venturi mixing throat. The air and gaseous fuel mix within the Venturi mixing throat before the mixture is combusted at the flame ports of the burners. Such burners are generally referred to as naturally aspirated gas burners. 
     Naturally aspirated gas burners can efficiently burn gaseous fuel. However, a power output of naturally aspirated gas burners is limited by the ability to entrain a suitable volume of air into the Venturi mixing throat with the jet of gaseous fuel. Moreover, there is a trend in the cooking appliance market toward high-powered burners in order to speed up cooking tasks. Thus, to provide increased entrainment of air, certain gas burners include a fan or air pump that supplies pressurized air for mixing with the jet of gaseous fuel. Such gas burners are generally referred to as forced air gas burners. 
     While offering increased power, known forced air gas burners suffer from various drawbacks. For example, known forced air gas burners use a linear piston pump, in which a piston is driven back and forth in a cylinder using an alternating magnetic field to displace air in a cyclic manner. However, linear piston pumps are relatively loud, and the output flow of air is presented in a rough, pulsing manner. The pulsing is visible in the flames, adds noise to the burner flames, and easily can overexcite any pneumatic valve actuators (if used) into resonance and chattering. Alternatively, certain forced air burners use bellow style air pumps which use a lever driven back and forth to deflect one or more diaphragms and move air. Pumps using multiple bellows may provide a smoother output of air having less pulsation amplitude and noise as compared to linear piston type pumps. However, as the resilient elastomer diaphragm is heated during normal operation, the diaphragm stiffness may change significantly, and the output of the pump may vary accordingly. 
     Accordingly, a cooktop appliance including an improved forced air gas burner would be desirable. More specifically, a gas burner assembly that offers high rates of heating using boost air that is consistent, reliable, and quiet would be particularly beneficial. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention. 
     In a first example embodiment, a gas burner assembly for a cooktop appliance is provided. The gas burner assembly includes a boost burner including a plurality of boost flame ports in fluid communication with a boost fuel chamber for receiving a flow of boost fuel and an air pump for selectively urging a flow of air into the boost fuel chamber. A temperature sensor is positioned proximate the air pump and a controller is operably coupled to the air pump and the temperature sensor. The controller is configured for obtaining a measured temperature using the temperature sensor and adjusting the operation of the air pump based at least in part on the measured temperature. 
     In a second example embodiment, a gas burner assembly for a cooktop appliance is provided. The gas burner assembly includes a boost burner including a plurality of boost flame ports in fluid communication with a boost fuel chamber for receiving a flow of boost fuel and an air pump for selectively urging a flow of air into the boost fuel chamber. A pressure sensor is operably coupled to the air pump and a controller is operably coupled to the air pump and the pressure sensor. The controller being configured for obtaining a measured pressure of the flow of air using the pressure sensor, determining that the measured pressure has dropped below a predetermined threshold pressure, and stopping the air pump in response to determining that the measured pressure has dropped below the predetermined threshold pressure. 
     In a third example embodiment, a method of operating a gas burner assembly is provided. The gas burner assembly includes a plurality of boost flame ports in fluid communication with a boost fuel chamber for receiving a flow of boost fuel, an air pump for selectively urging a flow of air into the boost fuel chamber, and a temperature sensor positioned proximate the air pump. The method includes obtaining a measured temperature using the temperature sensor and adjusting the operation of the air pump based at least in part on the measured temperature. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures. 
         FIG. 1  provides a top, plan view of a cooktop appliance according to an example embodiment of the present disclosure. 
         FIG. 2  is a side elevation view of a gas burner assembly that may be used with the exemplary cooktop appliance of  FIG. 1  according to an exemplary embodiment of the present subject matter. 
         FIG. 3  is an exploded view of the example gas burner of assembly  FIG. 2 . 
         FIG. 4  is a section view of the example gas burner assembly of  FIG. 2 . 
         FIG. 5  is another section view of the example gas burner assembly of  FIG. 2 . 
         FIG. 6  is a perspective view of an injet of the example gas burner assembly of  FIG. 2 . 
         FIG. 7  is an exploded view of the injet of  FIG. 7 . 
         FIG. 8  is a section view of the injet of  FIG. 7 . 
         FIG. 9  depicts certain components of a controller according to example embodiments of the present subject matter. 
         FIG. 10  is a schematic view of a gas burner assembly and a fuel supply system according to an example embodiment of the present subject matter. 
         FIG. 11  is a perspective view of a pressurized air source that may be used with the exemplary gas burner assembly of  FIG. 2  according to an exemplary embodiment of the present subject matter. 
         FIG. 12  is a method of operating a gas burner assembly in accordance with one embodiment of the present disclosure. 
     
    
    
     Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention. 
     DETAILED DESCRIPTION 
     Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
     The present disclosure relates generally to a gas burner for a cooktop appliance  100 . Although cooktop appliance  100  is used below for the purpose of explaining the details of the present subject matter, it will be appreciated that the present subject matter may be used in or with any other suitable appliance in alternative example embodiments. For example, the gas burner described below may be used on other types of cooking appliances, such as single or double oven range appliances. Cooktop appliance  100  is used in the discussion below only for the purpose of explanation, and such use is not intended to limit the scope of the present disclosure to any particular style of appliance. 
       FIG. 1  illustrates an exemplary embodiment of a cooktop appliance  100  of the present disclosure. Cooktop appliance  100  may be, e.g., fitted integrally with a surface of a kitchen counter, may be configured as a slide-in cooktop unit, or may be a part of a free-standing range cooking appliance. Cooktop appliance  100  includes a top panel  102  that includes one or more heating sources, such as heating elements  104  for use in, e.g., heating or cooking. Top panel  102 , as used herein, refers to any upper surface of cooktop appliance  100  on which utensils may be heated and therefore food cooked. In general, top panel  102  may be constructed of any suitably rigid and heat resistant material capable of supporting heating elements  104 , cooking utensils, and/or other components of cooktop appliance  100 . By way of example, top panel  102  may be constructed of enameled steel, stainless steel, glass, ceramics, and combinations thereof. 
     According to the illustrated embodiment, cooktop appliance  100  is generally referred to as a “gas cooktop,” and heating elements  104  are gas burners. For example, one or more of the gas burners in cooktop appliance  100  may be a gas burner  120  described below. As illustrated, heating elements  104  are positioned on and/or within top panel  102  and have various sizes, as shown in  FIG. 1 , so as to provide for the receipt of cooking utensils (i.e., pots, pans, etc.) of various sizes and configurations and to provide different heat inputs for such cooking utensils. 
     In addition, cooktop appliance  100  may include one or more grates  106  configured to support a cooking utensil, such as a pot, pan, etc. In general, grates  106  include a plurality of elongated members  108 , e.g., formed of cast metal, such as cast iron. The cooking utensil may be placed on the elongated members  108  of each grate  106  such that the cooking utensil rests on an upper surface of elongated members  108  during the cooking process. Heating elements  104  are positioned underneath the various grates  106  such that heating elements  104  provide thermal energy to cooking utensils above top panel  102  by combustion of fuel below the cooking utensils. 
     According to the illustrated example embodiment, a user interface panel or control panel  110  is located within convenient reach of a user of cooktop appliance  100 . For this example embodiment, control panel  110  includes control knobs  112  that are each associated with one of heating elements  104 . Control knobs  112  allow the user to activate each heating element  104  and regulate the amount of heat input each heating element  104  provides to a cooking utensil located thereon, as described in more detail below. Although cooktop appliance  100  is illustrated as including control knobs  112  for controlling heating elements  104 , it will be understood that control knobs  112  and the configuration of cooktop appliance  100  shown in  FIG. 1  is provided by way of example only. More specifically, control panel  110  may include various input components, such as one or more of a variety of touch-type controls, electrical, mechanical or electro-mechanical input devices including rotary dials, push buttons, and touch pads. 
     According to the illustrated embodiment, control knobs  112  are located within control panel  110  of cooktop appliance  100 . However, it should be appreciated that this location is used only for the purpose of explanation, and that other locations and configurations of control panel  110  and control knobs  112  are possible and within the scope of the present subject matter. Indeed, according to alternative embodiments, control knobs  112  may instead be located directly on top panel  102  or elsewhere on cooktop appliance  100 , e.g., on a backsplash, front bezel, or any other suitable surface of cooktop appliance  100 . Control panel  110  may also be provided with one or more graphical display devices, such as a digital or analog display device designed to provide operational feedback to a user. 
     Turning now to  FIGS. 2 through 8 , a gas burner  120  according to an example embodiment of the present disclosure is described. Gas burner  120  may be used in cooktop appliance  100 , e.g., as one of heating elements  104 . Thus, gas burner  120  is described in greater detail below in the context of cooktop appliance  100 . However, it will be understood that gas burner  120  may be used in or with any other suitable cooktop appliance in alternative example embodiments. 
     Gas burner  120  includes a burner body  122 . Burner body  122  generally defines a first burner ring or stage (e.g., a primary burner  130 ) and a second burner ring or stage (e.g., a boost burner  132 ). More specifically, primary burner  130  generally includes a plurality of naturally aspirated or primary flame ports  134  and a primary fuel chamber  136  which are defined at least in part by burner body  122 . Similarly, boost burner  132  generally includes a plurality of forced air or boost flame ports  138  and a boost fuel chamber  140  which are defined at least in part by burner body  122 . 
     As illustrated, primary flame ports  134  and boost flame ports  138  may both be distributed in rings on burner body  122 . In addition, primary flame ports  134  may be positioned concentric with boost flame ports  138 . Further, primary flame ports  134  (and primary burner  130 ) may be positioned below boost flame ports  138  (and boost burner  132 ). Such positioning of primary burner  130  relative to boost burner  132  may improve combustion of gaseous fuel when gas burner assembly  120  is set to the boost position. For example, flames at primary burner  130  may assist with lighting gaseous fuel at boost burner  132  due to the position of primary burner  130  below boost burner  132 . 
     With reference to  FIGS. 2 through 8 , gas burner  120  also includes an injet assembly  150 . Injet assembly  150  may be positioned below top panel  102 , e.g., below an opening  103  ( FIG. 3 ) of top panel  102 . Conversely, burner body  122  may be positioned on top panel  102 , e.g., over opening  103  of top panel  102 . Thus, burner body  122  may cover opening  103  of top panel  102  when burner body  122  is positioned on top panel  102 . When burner body  122  is removed from top panel  102 , injet assembly  150  below top panel  102  is accessible through opening  103 . Thus, e.g., a fuel orifice(s) of gas burner  120  on injet assembly  150  may be accessed by removing burner body  122  from top panel  102 , and an installer may reach through opening  103  (e.g., with a wrench or other suitable tool) to change out the fuel orifice(s) of gas burner  120 . 
     Injet assembly  150  is configured for directing a flow of gaseous fuel to primary flame ports  134  of burner body  122 . Thus, injet assembly  150  may be coupled to a gaseous fuel source  152 , as described in more detail below with reference to  FIG. 10 . During operation of gas burner  120 , gaseous fuel from gaseous fuel source  152  may flow from injet assembly  150  into a vertical Venturi mixing tube  154 . In particular, injet assembly  150  includes a first gas orifice  156  that is in fluid communication with a gas passage  158 . A jet of gaseous fuel from gaseous fuel source  152  may exit injet assembly  150  at first gas orifice  156  and flow towards vertical Venturi mixing tube  154 . Between first gas orifice  156  and vertical Venturi mixing tube  154 , the jet of gaseous fuel from first gas orifice  156  may entrain air into vertical Venturi mixing tube  154 . Air and gaseous fuel may mix within vertical Venturi mixing tube  154  prior to flowing into primary fuel chamber  136  and through primary flame ports  134  where the mixture of air and gaseous fuel may be combusted. 
     Injet assembly  150  is also configured for directing a flow of air and gaseous fuel to boost flame ports  138  of burner body  122 . Thus, as discussed in greater detail below, injet assembly  150  may be coupled to pressurized air source  160  in addition to gaseous fuel source  152 . During boosted operation of gas burner  120 , a mixed flow of gaseous fuel from gaseous fuel source  152  and air from pressurized air source  160  may flow from injet assembly  150 , through an inlet tube  162 , and into boost fuel chamber  140  prior to flowing to boost flame ports  138  where the mixture of gaseous fuel and air may be combusted at boost flame ports  138 . 
     In addition to first gas orifice  156 , injet assembly  150  also includes a second gas orifice  164 , a mixed outlet nozzle  166 , and an injet body  168 . Injet body  168  defines an air passage  170  and gas passage  158 . Air passage  170  may be in fluid communication with pressurized air source  160 . For example, a pipe or conduit may extend between pressurized air source  160  and injet body  168 , and pressurized air from pressurized air source  160  may flow into air passage  170  via such pipe or conduit. Gas passage  158  may be in fluid communication with gaseous fuel source  152 . For example, a pipe or conduit may extend between gaseous fuel source  152  and injet body  168 , and gaseous fuel from gaseous fuel source  152  may flow into gas passage  158  via such pipe or conduit. In certain example embodiments, injet body  168  defines a single inlet  172  for air passage  170  through which the pressurized air from pressurized air source  160  may flow into air passage  170 , and injet body  168  defines a single inlet  174  for gas passage  158  through which the pressurized air from gaseous fuel source  152  may flow into gas passage  158 . 
     First gas outlet orifice  156  is mounted to injet body  168 , e.g., at a first outlet of gas passage  158 . Thus, gaseous fuel from gaseous fuel source  152  may exit gas passage  158  through first gas outlet orifice  156 , and gas passage  158  is configured for directing a flow of gaseous fuel through injet body  168  to first gas outlet orifice  156 . On injet body  168 , first gas outlet orifice  156  is oriented for directing a flow of gaseous fuel towards vertical Venturi mixing tube  154  and/or primary flame ports  134 , as discussed above. 
     Second gas orifice  164  and injet body  168 , e.g., collectively, form an eductor mixer  176  within a mixing chamber  178  of injet body  168 . Eductor mixer  176  is configured for mixing pressurized air from air passage  170  with gaseous fuel from gas passage  158  in mixing chamber  178 . In particular, an outlet  180  of air passage  170  is positioned at mixing chamber  178 . A jet of pressurized air from pressurized air source  160  may flow from air passage  170  into mixing chamber  178  via outlet  180  of air passage  170 . Second gas orifice  164  is positioned within injet body  168  between mixing chamber  178  and gas passage  158 . Gaseous fuel from gaseous fuel source  152  may flow from gas passage  158  into mixing chamber  178  via second gas orifice  164 . As an example, second gas orifice  164  may be a plate that defines a plurality of through holes  182 , and the gaseous fuel in gas passage  158  may flow through holes  182  into mixing chamber  178 . 
     The jet of pressurized air flowing into mixing chamber  178  via outlet  180  of air passage  170  may draw and entrain gaseous fuel flowing into mixing chamber  178  via second gas orifice  164 . In addition, as the gaseous fuel is entrained into the air, a mixture of air and gaseous fuel is formed within mixing chamber  178 . From mixing chamber  178 , the mixture of air and gaseous fuel may flow from mixing chamber  178  via mixed outlet nozzle  166 . In particular, mixed outlet nozzle  166  is mounted to injet body  168  at mixing chamber  178 , and mixed outlet nozzle  166  is oriented on injet body  168  for directing the mixed flow of air and gaseous fuel from mixing chamber  178 , through inlet tube  162 , into boost fuel chamber  140 , and/or towards boost flame ports  138 , as discussed above. 
     Burner body  122  may be positioned over injet body  168 , e.g., when burner body  122  is positioned on top panel  102 . In addition, first gas orifice  156  may be oriented on injet body  168  such that first gas orifice  156  directs the flow of gaseous fuel upwardly towards vertical Venturi mixing tube  154  and primary flame ports  134 . Similarly, mixed outlet nozzle  166  may be oriented on injet body  168  such that mixed outlet nozzle  166  directs the mixed flow of air and gaseous fuel upwardly towards inlet tube  162  and boost flame ports  138 . 
     First and second gas orifices  156 ,  164  may be removeable from injet body  168 . First and second gas orifices  156 ,  164  may also be positioned on injet body  168  directly below burner body  122 , e.g., when burner body  122  is positioned on top panel  102 . Thus, e.g., first and second gas orifices  156 ,  164  may be accessed by removing burner body  122  from top panel  102 , and an installer may reach through opening  103  (e.g., with a wrench or other suitable tool) to change out first and second gas orifices  156 ,  164 . 
     Injet assembly  150  also includes a pneumatically actuated gas valve  200 . Pneumatically actuated gas valve  200  may be positioned within injet body  168 , and pneumatically actuated gas valve  200  is adjustable between a closed configuration and an open configuration. In the closed configuration, pneumatically actuated gas valve  200  blocks the flow of gaseous fuel through gas passage  158  to second gas orifice  164 , eductor mixer  176 , and/or mixed outlet nozzle  166 . Conversely, pneumatically actuated gas valve  200  permits the flow of gaseous fuel through gas passage  158  to second gas orifice  164 /eductor mixer  176  in the open configuration. Pneumatically actuated gas valve  200  is configured to adjust from the closed configuration to the open configuration in response to the flow of air through air passage  170  to outlet  180  of air passage  170 . Thus, e.g., pneumatically actuated gas valve  200  is in fluid communication with air passage  170  and opens in response to air passage  170  being pressurized by air from pressurized air source  160 . As an example, pneumatically actuated gas valve  200  may be positioned on a branch of air passage  170  relative to outlet  180  of air passage  170 . 
     It will be understood that first gas outlet orifice  156  may be in fluid communication with gas passage  158  in both the open and closed configurations of pneumatically actuated gas valve  200 . Thus, first gas outlet orifice  156  may be positioned on gas passage  158  upstream of pneumatically actuated gas valve  200  relative to the flow of gas through gas passage  158 . Thus, e.g., pneumatically actuated gas valve  200  may not regulate the flow of gas through second gas orifice  164  but not first gas outlet orifice  156 . 
     As shown in  FIGS. 5 and 7 , pneumatically actuated gas valve  200  includes a diaphragm  202 , a seal  204 , and a plug  206 . Diaphragm  202  is positioned between air passage  170  and gas passage  158  within injet body  168 . For example, diaphragm  202  may be circular and may be clamped between a first injet body half  208  and a second injet body half  210 . In particular, first and second injet body halves  208 ,  210  may be fastened together with diaphragm  202  positioned between first and second injet body halves  208 ,  210 . 
     Seal  204  is mounted to injet body  168  within gas passage  158 . Plug  206  is mounted to diaphragm  202 , e.g., such that plug  206  travels with diaphragm  202  when diaphragm  202  deforms. Plug  206  is positioned against seal  204  when pneumatically actuated gas valve  200  is closed. A spring  212  may be coupled to plug  206 . Spring  212  may urge plug  206  towards seal  204 . Thus, pneumatically actuated gas valve  200  may be normally closed. 
     When air passage  170  is pressurized by air from pressurized air source  160 , diaphragm  202  may deform due to the pressure of air in air passage  170  increasing, and plug  206  may shift away from seal  204  as diaphragm  202  deforms. In such a manner, diaphragm  202 , seal  204 , and plug  206  may cooperate to open pneumatically actuated gas valve  200  in response to air passage  170  being pressurized by air from pressurized air source  160 . Conversely, diaphragm  202  may return to an undeformed state when air passage  170  is no longer pressurized by air from pressurized air source  160 , and plug  206  may shift against seal  204 . In such a manner, diaphragm  202 , seal  204  and plug  206  may cooperate to close pneumatically actuated gas valve  200  in response to air passage  170  no longer being pressurized by air from pressurized air source  160 . 
     Operation of cooktop appliance  100  and gas burner assemblies  120  may be controlled by electromechanical switches or by a controller or processing device  220  ( FIGS. 1 and 9 ) that is operatively coupled to control panel  110  for user manipulation, e.g., to control the operation of heating elements  104 . In response to user manipulation of control panel  110  (e.g., via control knobs  112  and/or a touch screen interface), controller  220  operates the various components of cooktop appliance  100  to execute selected instructions, commands, or other features. 
     As described in more detail below with respect to  FIG. 9 , controller  220  may include a memory and microprocessor, such as a general or special purpose microprocessor operable to execute programming instructions or micro-control code associated with appliance operation. Alternatively, controller  220  may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software. Control panel  110  and other components of cooktop appliance  100  may be in communication with controller  220  via one or more signal lines or shared communication busses. 
       FIG. 9  depicts certain components of controller  220  according to example embodiments of the present disclosure. Controller  220  can include one or more computing device(s)  220 A which may be used to implement methods as described herein. Computing device(s)  220 A can include one or more processor(s)  220 B and one or more memory device(s)  220 C. The one or more processor(s)  220 B can include any suitable processing device, such as a microprocessor, microcontroller, integrated circuit, an application specific integrated circuit (ASIC), a digital signal processor (DSP), a field-programmable gate array (FPGA), logic device, one or more central processing units (CPUs), graphics processing units (GPUs) (e.g., dedicated to efficiently rendering images), processing units performing other specialized calculations, etc. The memory device(s)  220 C can include one or more non-transitory computer-readable storage medium(s), such as RAM, ROM, EEPROM, EPROM, flash memory devices, magnetic disks, etc., and/or combinations thereof. 
     The memory device(s)  220 C can include one or more computer-readable media and can store information accessible by the one or more processor(s)  220 B, including instructions  220 D that can be executed by the one or more processor(s)  220 B. For instance, the memory device(s)  220 C can store instructions  220 D for running one or more software applications, displaying a user interface, receiving user input, processing user input, etc. In some implementations, the instructions  220 D can be executed by the one or more processor(s)  220 B to cause the one or more processor(s)  220 B to perform operations, e.g., such as one or more portions of methods described herein. The instructions  220 D can be software written in any suitable programming language or can be implemented in hardware. Additionally, and/or alternatively, the instructions  220 D can be executed in logically and/or virtually separate threads on processor(s)  220 B. 
     The one or more memory device(s)  220 C can also store data  220 E that can be retrieved, manipulated, created, or stored by the one or more processor(s)  220 B. The data  220 E can include, for instance, data to facilitate performance of methods described herein. The data  220 E can be stored in one or more database(s). The one or more database(s) can be connected to controller  220  by a high bandwidth LAN or WAN, or can also be connected to controller through one or more networks (not shown). The one or more database(s) can be split up so that they are located in multiple locales. In some implementations, the data  220 E can be received from another device. 
     The computing device(s)  220 A can also include a communication module or interface  220 F used to communicate with one or more other component(s) of controller  220  or cooktop appliance  100  over the network. The communication interface  220 F can include any suitable components for interfacing with one or more network(s), including for example, transmitters, receivers, ports, controllers, antennas, or other suitable components. 
     Referring now to  FIG. 10 , a schematic view of gas burner assembly  120  and a fuel supply system  230  will be described. In general, fuel supply system  230  is configured for selectively supplying gaseous fuel such as propane or natural gas to primary burner  130  and boost burner  132  to regulate the amount of heat generated by the respective stages. In particular, fuel supply system  230  is configured for selectively supplying gaseous fuel to only primary burner  130  or to both primary burner  130  and boost burner  132  depending upon the desired output of gas burner assembly  120  selected by a user of gas burner assembly  120 . Thus, primary burner  130  is separate or independent from boost burner  132 , e.g., such that primary burner  130  is not in fluid communication with boost burner  132  within gas burner assembly  120 . In such manner, gaseous fuel within gas burner assembly  120  does not flow between primary burner  130  and boost burner  132 . 
     As shown in  FIG. 10 , fuel supply system  230  includes a supply line  232  that may be coupled to pressurized gaseous fuel source  152 , such as a natural gas supply line or a propane tank. In this manner, a flow of supply fuel (indicated by arrow  234 ), such as gaseous fuel (e.g., natural gas or propane), is flowable from the pressurized gaseous fuel source  152  into supply line  232 . Fuel supply system  230  further includes a control valve  236  operably coupled to supply line  232  for selectively directing a metered amount of fuel to primary burner  130  and boost burner  132 . 
     More specifically, according to an exemplary embodiment, control knob  112  may be operably coupled to control valve  236  for regulating the flow of supply fuel  234 . In this regard, a user may rotate control knob  112  to adjust the position of control valve  236  and the flow of supply fuel  234  through supply line  232 . In particular, gas burner assembly  120  may have a respective heat output at each position of control knob  112  (and control valve  236 ), e.g., an off, high, medium, and low position. In addition, control knob  112  may be rotated to a lighting position to supply a suitable amount of gaseous fuel to primary burner  130  for ignition, which may be simultaneously achieved using, e.g., a spark electrode (not shown). 
     As best shown in  FIG. 10 , supply line  232  is split into a first branch (e.g., a primary fuel conduit  240 ) and a second branch (e.g., a boost fuel conduit  242 ) at a junction  244 , e.g., via a plumbing tee, wye, or any other suitable splitting device. In general, primary fuel conduit  240  extends from junction  244  to an orifice for primary flame ports  134  (such as first gas orifice  156 ), which is positioned for directing a flow of primary fuel  246  into gas burner assembly  120 , or more particularly into primary burner  130 . Similarly, boost fuel conduit  242  extends from junction  244  to an orifice for boost flame ports  138  (such as second gas orifice  164  or holes  182  defined therein), which is positioned for directing a flow of boost fuel  248  into boost burner  132 . Thus, supply line  232  is positioned upstream of primary and boost fuel conduits  240 ,  242  relative to a flow of gaseous fuel from fuel source  152  and primary and boost fuel conduits  240 ,  242  may separately supply the gaseous fuel from supply line  232  to primary burner  130  and boost burner  132 . 
     As explained above, boost burner  132  is a forced air or mechanically aspirated burner. Referring briefly to  FIGS. 10 and 11 , fuel supply system  230  includes a pressurized air source  160  which is generally configured for providing the flow of combustion air  250  to boost burner  132  for mixing with boost flow of fuel  248 . In this regard, for example, fuel supply system  230  includes an air supply conduit  252  that provides fluid communication between pressurized air source  160  and boost fuel chamber  140 , or more specifically, outlet  180  of air passage  172 . Referring now briefly to  FIG. 11 , an air pump  260  will now be described according to an exemplary embodiment. According to exemplary embodiments, air pump  260  may be used as pressurized air source  160  described above. 
     Specifically, as illustrated, air pump  260  is a bellows-style air pump. As shown, air pump  260  includes a lever arm  262  that is pivotally mounted to a post  264  within a pump housing  266 . Mounted to a distal end of lever arm  262  is a magnet  268  which may be driven back and forth by an alternating magnetic field generated by a magnetic field generator  270 . In addition, a resilient diaphragm  272  is positioned over a pump body  274  adjacent lever arm  262 . Pump body  274  may be fluidly coupled to an aperture (not shown) in pump housing  266  which is configured for receiving an air supply conduit, e.g., such as air supply conduit  252 . 
     During operation of air pump  260 , magnetic field generator  270  drives a magnet  268  and thus lever arm  262  back and forth to deflect or deform diaphragm  272 , which is typically made from a resilient elastomer material, such as rubber. As diaphragm  272  is deflected, air within diaphragm  272  and pump body  274  is compressed and discharged out a pump housing  266  and into air supply conduit  252 . Notably, air pump  260  may be operated off AC line voltage having a frequency of 60 Hz. Thus, the flow of air  250  has a tendency to pulse at the same frequency. 
     Although an exemplary air pump  260  is described above, other types, positions, and configurations of pressurized air source  160  or air pump  260  are possible and within the scope of the present subject matter. For example, according to an exemplary embodiment, pressurized air source  160  may be a fan or an air pump, such as an axial or centrifugal fan, or any other device suitable for urging a flow of combustion air, such as an air compressor or a centralized compressed air system. Pressurized air source  160  may be configured for supplying the flow of combustion air  250  at any suitable gage pressure, such as a half to one psig. 
     As described above, fuel supply system  230  includes pneumatically actuated gas valve  200 , which is a pressure controlled valve operably coupled with pressurized air source  160  (e.g., air pump  260 ) and to boost fuel conduit  242 . Pneumatically actuated gas valve  200  is generally configured for regulating the flow of boost fuel  248  passing through boost fuel conduit  242 , as described in detail above. Specifically, pneumatically actuated gas valve  200  is configured for stopping the flow of boost fuel  248  when a pressure of the flow of air  250  drops below a predetermined pressure or threshold. The predetermined pressure or threshold may be selected by a user or the manufacturer, may be associated with a specific condition or event, may be selected to correspond to an operating condition of fuel supply system  230 , or may be determined in any other suitable manner. 
     According to an exemplary embodiment, the predetermined pressure is a minimum combustion air threshold pressure, i.e., the pressure generated by a properly operating pressurized air source  160  for generating a flow of combustion air  250  for desired combustion. In this regard, if pressurized air source  160  fails to provide a flow of combustion air  250  suitable to support operation of boost burner  132 , controller  220  may sense the low pressure associated with the flow of combustion air  250  and stop the flow of boost fuel  248 . Notably, using such a configuration, controller  220  (or another suitable timing device) may be directly coupled to pressurized air source  160  and may not need to be operably coupled to pneumatically actuated gas valve  200 . 
     As shown in  FIG. 10 , a boost button  280  may be operably coupled to pressurized air source  160  through controller  220 . In this regard, boost button  280  may be a momentary push button, a toggle switch, or any other suitable button or switch that is operably coupled with controller  220  for providing an indication to gas burner assembly  120  and pressurized air source  160  to enter boost mode. Thus, when boost burner button  280  is pressed, controller  220  may operate pressurized air source  160  to start boost mode operation. As an example, boost flame ports  138  may be activated by pressing a boost burner button  280  on control panel  110 . In response to a user actuating boost burner button  280 , pressurized air source  160  may be activated, e.g., with a timer control or with controller  220 . 
     Specifically, controller  220  may include a power supply  286  that is operably coupled to air pump  260  for regulating its operation. For example, controller  220  may operate power supply  286  to drive air pump  260  in a manner that compensates for temperature response characteristics of air pump  260 , as described below. According to exemplary embodiments, power supply  286  may regulate operation of air pump  260  by varying an input voltage or power. Alternatively, the power level of air pump  260  may be adjusted by manipulating a pump control signal. In this regard, for example, power supply  286  may be a dedicated inverter power supply and the pump control signal may be any suitable digital control signal, such as a pulse width modulated signal having a duty cycle that is roughly proportional to the power level of air pump  260 . In this regard, for example, a fifty percent duty cycle may drive air pump  260  at fifty percent of its rated speed, an eighty percent duty cycle may drive air pump  260  at eighty percent of its rated speed, etc. It should be appreciated that other means for controlling the power level and speed of air pump  260  are possible and within the scope of the present subject matter. 
     As used herein, “temperature response characteristics” are intended to refer to the operating or performance characteristics of air pump  260  which are affected by temperature changes of air pump  260  or the surrounding environment. More specifically, according to an exemplary embodiment, temperature response characteristics are intended to represent data (empirical or theoretical) or information regarding the performance of diaphragm  272  as it heats up during operation or from rising ambient temperatures. 
     In this regard, diaphragm  272  is commonly made from a resilient elastomer material that flexes or deforms to compress and discharge air from pump body  274 . The stiffness of elastomers may change significantly from room temperature to elevated temperatures commonly experienced by air pumps of cooking appliances. As a result, while gas burner  120  may be calibrated to run at a precise fuel to air ratio at room temperature, that actual ratio provided by fuel supply system  230  may drift away from its target if diaphragm  272  does not pump air as precise as expected. Notably, a relationship may be established between a temperature of air pump  260  or its surroundings and the corresponding airflow rate for a given input power. This data, which generally correlates the measured temperature to actual performance (e.g., compensating for temperature response characteristics) of air pump  260  may be stored in a data table within controller  220 . 
     Notably, in order to obtain such temperature data, cooktop appliance  100  or gas burner assembly  120  may further include a temperature sensor  290  which is generally configured for measuring a temperature of diaphragm  272 , of air pump  260 , of gas burner  120 , or of any other item or location that has a reasonable correlation with the performance of air pump  260  as temperature changes are experienced. For example, according to the illustrated embodiment, temperature sensor  290  is mounted directly to air pump  260 , e.g., on pump housing  266 . Alternatively, temperature sensor  290  may be positioned anywhere else proximate to air pump  260  for providing data indicative of the operating temperature of air pump  260 . 
     As used herein, “temperature sensor” or the equivalent is intended to refer to any suitable type of temperature measuring system or device positioned at any suitable location for measuring the desired temperature. Thus, for example, temperature sensor  290  may be any suitable type of temperature sensor, such as a thermistor, a thermocouple, etc. In addition, temperature sensor  290  may be positioned at any suitable location and may output a signal, such as a voltage, to controller  220  that is proportional to and/or indicative of the temperature of air pump  260 , diaphragm  272 , or the ambient environment. 
     According to exemplary embodiments, it may also be desirable to measure a pressure of the flow of air  250  downstream of air pump  260 . In this regard, for example, a pressure sensor  292  may be operably coupled to air supply conduit  252  and positioned between pump housing  266  and outlet  180 . As used herein, “pressure sensor” or the equivalent is intended to refer to any suitable type of pressure measuring system or device positioned at any suitable location for measuring the desired pressure. Thus, for example, pressure sensor  292  may be any suitable type of pressure sensor, such as a capacitive pressure transducer, a piezoresistive transducer, etc. In addition, pressure sensor  292  may be positioned at any suitable location and may output a signal, such as a voltage, to controller  220  that is proportional to and/or indicative of the pressure downstream of air pump  260 , e.g., within air supply conduit  252 . 
     According to exemplary embodiments, pressure sensor  292  may be generally configured for monitoring the output pressure of air pump  260  and controller  220  may adjust the operation of gas burner  120  accordingly. For example, controller  220  may obtain a measured pressure of the flow of air  250  using pressure sensor  292 . If controller  220  determines that the measured pressure has dropped below a predetermined threshold pressure, such as a minimum combustion air threshold pressure, controller  220  may stop the air pump  260  and/or shut off control valve  236 . In this manner, pressure sensor  292  may act as a redundant safety measure to prevent the boost flow of fuel  248  from passing into boost fuel chamber  140  in the event of an air pump  260  failure or inability to compensate for temperature related diaphragm issues. In addition, according to alternative embodiments, temperature sensor  290  may be removed altogether, and pressure sensor  292  may be used to provide closed-loop feedback regarding the output pressure of air pump  260 , and controller  220  may compensate accordingly. 
     Now that the construction and configuration of gas burner assembly  120  and fuel supply system  230  have been described according to exemplary embodiments of the present subject matter, an exemplary method  300  for operating a gas burner assembly will be described according to an exemplary embodiment of the present subject matter. Method  300  can be used to operate gas burner assembly  120 , or any other suitable heating element or cooktop appliance. In this regard, for example, controller  220  may be configured for implementing some or all steps of method  300 . Further, it should be appreciated that the exemplary method  300  is discussed herein only to describe exemplary aspects of the present subject matter, and is not intended to be limiting. 
     Referring now to  FIG. 12 , method  300  includes, at step  310 , obtaining a measured temperature using a temperature sensor positioned proximate an air pump of a boosted gas burner. For example, continuing the example from above, controller  220  may use temperature sensor  292  obtain an approximate temperature of air pump  260 . Controller  220  may in use empirical data related to the temperature response characteristics of the particular air pump  260  to determine whether a power supply should be regulated to adjust the operation of air pump  260  to provide the desired flow rate of the flow of air  250 . 
     Specifically, step  320  includes adjusting the operation of the air pump based at least in part on the measured temperature, e.g., by increasing a power applied to the air pump as the measured temperature increases. In this regard, controller  220  may use a data table, equation, or other information regarding the empirical or theoretical relationship between air pump temperature and flow rate to determine an appropriate voltage or power input which is needed to achieve the target air flow rate. 
     According to an exemplary embodiment, as a redundant measure to steps  310  and  320 , method  300  may include at step  330 , obtaining a measured pressure of the flow of air using a pressure sensor operably coupled to the air pump. For example, controller  220  may obtain a measured pressure downstream of air pump  260 , e.g., within air supply conduit  252 . If the measured pressure is below the desired pressure, controller  220  may increase the power input or duty cycle from power supply  286  to speed up the operation of air pump  260  and increase the air flow rate. 
     Alternatively, step  340  includes determining that the measured pressure has dropped below a predetermined threshold pressure. For example the predetermined threshold pressure may be associated with a minimum combustion pressure for boost burner  132 . Step  350  includes stopping the air pump in response to determining that the measured pressure has dropped below the predetermined threshold pressure. Thus, steps  330  through  350  ensure that boost fuel is not provided to boost burner  132  in the event of an air pump failure. 
       FIG. 12  depicts an exemplary control method having steps performed in a particular order for purposes of illustration and discussion. Those of ordinary skill in the art, using the disclosures provided herein, will understand that the steps of any of the methods discussed herein can be adapted, rearranged, expanded, omitted, or modified in various ways without deviating from the scope of the present disclosure. Moreover, although aspects of the methods are explained using gas burner assembly  120  and fuel supply system  230  as an example, it should be appreciated that these methods may be applied to the operation of any suitable gas burner assembly or cooktop appliance. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.