Gas ignition system for a gas cooking appliance

Abstract

A gas ignition system for a gas cooking appliance is provided. The gas ignition system includes an ignition component operable to ignite gas based at least in part on an enable signal. The gas ignition system further includes an ignition sensor configured to provide a feedback signal indicative of a temperature of the ignition component. The gas ignition system further includes an ignition controller configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

Description

FIELD

[0001] Example aspects of the present disclosure relate generally to gas cooking appliances such as gas ovens, and more particularly, to gas control systems for gas cooking appliances.BACKGROUND

[0002] Gas cooking appliances generally include one or more gas heating elements configured to provide heat to cook food items. Cooking appliances, such as ovens, include heating elements positioned within a cooking chamber of the gas cooking appliance. Further, cooking appliances, such as cooktops, may include heating elements positioned atop the cooking appliance. Cooking appliances that include both an oven and a cooktop are commonly referred to as “ranges.”SUMMARY

[0003] Aspects and advantages of embodiments of the present disclosure will be set forth in part in the following description, or can be learned from the description, or can be learned through practice of the embodiments.

[0004] One example aspect of the present disclosure is directed to a gas ignition system for a gas cooking appliance. The gas ignition system includes an ignition component operable to ignite gas based at least in part on an enable signal. The gas ignition system further includes an ignition sensor configured to provide a feedback signal indicative of a temperature of the ignition component. The gas ignition system further includes an ignition controller configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

[0005] Another example aspect of the present disclosure is directed to method for providing gas to an ignition component of a gas cooking appliance. The method includes receiving, from an ignition sensor, a feedback signal indicative of a temperature of the ignition component. The method further includes determining a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times. The method further includes providing, by an ignition controller, an enable signal based at least in part on the plurality of feedback samples. The method further includes providing gas to the ignition component based at least in part on the enable signal.

[0006] Another example aspect of the present disclosure is directed to a gas cooking appliance. The gas cooking appliance includes a cooking chamber. The gas cooking appliance further includes an ignition component operable to ignite gas based at least in part on an enable signal. The gas cooking appliance further includes an ignition sensor configured to provide a feedback signal indicative of a temperature of the ignition component. The gas cooking appliance further includes an ignition controller configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

[0007] These and other features, aspects and advantages of various embodiments 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 present disclosure and, together with the description, serve to explain the related principles.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Detailed discussion of embodiments directed to one of ordinary skill in the art are set forth in the specification, which makes reference to the appended figures, in which:

[0009] FIG. 1 illustrates a front perspective view of a gas cooking appliance according to example embodiments of the present subject matter;

[0010] FIG. 2 illustrates a side cross-sectional view of the example gas cooking appliance of FIG. 1 according to example embodiments of the present subject matter;

[0011] FIG. 3 depicts an example circuit schematic of a gas ignition system according to example embodiments of the present disclosure;

[0012] FIG. 4 depicts an example circuit schematic of an ignition controller according to example embodiments of the present disclosure;

[0013] FIG. 5 provides an example waveform of a gas ignition system according to example embodiments of the present disclosure; and

[0014] FIG. 6 provides a flowchart of an example method for providing gas to an ignition component of a gas cooking appliance according to example embodiments of the present disclosure.

[0015] Repeat use of reference characters in the present specification and drawings is intended to represent the same and / or analogous features or elements of the present invention.DETAILED DESCRIPTION

[0016] Reference now will be made in detail to embodiments, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the embodiments, not limitation of the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments without departing from the scope or spirit of the present disclosure. 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 aspects of the present disclosure cover such modifications and variations.

[0017] Gas cooking appliances may generally include one or more gas heating elements configured to provide heat to cook food items. Each heating element may include an ignition component configured to ignite gas supplied, for example, by a gas valve. If the gas is provided and the ignition component fails to ignite, a potentially hazardous situation is created as the gas may continue to be provided. Ensuring that an ignition component will ignite (e.g., provide proof that an ignition component is capable of igniting gas) before allowing gas flow to the ignition component may be important in ensuring the safety of a user. As such, electrical controls for gas cooking appliances (e.g., gas ovens) may fall under UL 60730 Class C. This may require a second level failure mode and effects analysis (FMEA).

[0018] Some gas cooking appliances use direct spark ignition and flame monitoring, however these systems may be expensive, increasing the cost of manufacturing the appliance. Alternatively, negative temperature coefficient (NTC) ignitors may be used. With this type of ignitor, a bi-metal solution may allow gas flow after a certain current level is reached. For example, the increase in current as the ignitor heats up energizes the bi-metal switch and, in turn, opens a valve to allow the flow of gas. However, these heating systems may be expensive and may not fit in smaller gas cooking appliances as the components of the system may take up a large amount of space. Accordingly, the present disclosure includes a hardware solution for providing proof that an ignition component, such as a hot surface igniter (HSI), is capable of igniting gas in a gas fueled cooking system.

[0019] One aspect of the present disclosure is directed to a gas ignition system for a gas cooking appliance. The gas ignition system may provide proof that an ignition component, such as a hot surface igniter (HSI), is in a voltage range suitable to ignite gas while also providing second level failure redundancy. For instance, the gas ignition system may sample a feedback signal indicative of a temperature of the ignition component at multiple times. The feedback signal may be determined using a shunt sensor (e.g., shunt resistor), such that the feedback signal indicates a shunt voltage level of the periodic alternating current supplied to the ignition component (e.g., HSI).

[0020] Specifically, the ignition component may be a positive temperature coefficient (PTC) hot surface igniter (HSI). The shunt voltage measured by the feedback signal may decrease as the temperature of the HSI increases (e.g., heats up). As such, the feedback signal may be sampled at a period in the alternating current signal that is correspondent to the ignition temperature of gas. The sample may be compared to a threshold value indicating a reference voltage. For example, a shunt voltage greater than the reference voltage may indicate that the HSI is not capable of ignition while a shunt voltage less than the reference voltage may indicate that the HSI is capable of ignition.

[0021] Second level redundancy may be proven by the changing of states of the feedback signal with respect to the threshold value as well as by measuring the feedback signal at different times. Specifically, the period of the feedback signal correspondent to the ignition temperature of gas may be defined relative to the zero cross and / or the peak of the feedback signal. As such, the feedback signal may be sampled at multiple times, each time corresponding to a different phase of the AC signal over a period of time.

[0022] For instance, the feedback signal may be sampled at multiple times over a period of time between the zero cross of the feedback signal and a peak of the feedback signal. Accordingly, a first feedback sample may be measured at a first time corresponding to a zero cross (e.g., phase of 0 radians) of the feedback signal. A second feedback sample may be measured at a second time after the zero cross. The second time may correspond to a phase of the feedback signal that is associated with a temperature of the HSI capable of igniting gas, such as a phase of π / 8 radians. A third feedback sample may be measured at a third time corresponding to a peak (e.g., phase of π / 2 radians) of the feedback signal after the zero cross.

[0023] Second level redundancy may be achieved by comparing each feedback sample (e.g., first, second, and third) to the threshold value, indicating that the feedback signal is not in a fault state by indicating a false temperature (e.g., providing a constant voltage). For instance, the HSI may be at a temperature capable of ignition when the first feedback sample and the second feedback sample are below the threshold value and the third feedback sample is above the threshold value.

[0024] Example aspects of the present disclosure provide many technical effects and benefits. For example, the gas ignition system of the present disclosure may provide needed redundancy for electronic control of the gas cooking appliances, such as gas ovens. In addition, the use of a controller, such as an IC chip, instead of discreet components greatly reduces costs and board space while maintaining functionality. Further, the gas control system provided herein provides for a smaller footprint due to, for example, the HSI ignition component and electronically controlled gas valve.

[0025] As used herein, the terms “first,”“second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “includes” and “including” are intended to be inclusive in a manner similar to the term “comprising.” Similarly, the term “or” is generally intended to be inclusive (e.g., “A or B” is intended to mean “A or B or both”). The term “at least one of” in the context of, e.g., “at least one of A, B, and C” refers to only A, only B, only C, or any combination of A, B, and C. In addition, here and throughout the specification and claims, range limitations may be combined and / or interchanged. Such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. The singular forms “a,”“an,” and “the” include plural references unless the context clearly dictates otherwise.

[0026] Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “generally,”“about,”“approximately,” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and / or systems. For example, the approximating language may refer to being within a 10 percent margin, i.e., including values within ten percent greater or less than the stated value. In this regard, for example, when used in the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction, e.g., “generally vertical” includes forming an angle of up to ten degrees in any direction, e.g., clockwise or counterclockwise, with the vertical direction V.

[0027] The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” In addition, references to “an embodiment” or “one embodiment” does not necessarily refer to the same embodiment, although it may. Any implementation described herein as “exemplary” or “an embodiment” is not necessarily to be construed as preferred or advantageous over other implementations. Moreover, 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 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.

[0028] The terms “coupled,”“fixed,”“attached to,” and the like refer to both direct coupling, fixing, or attaching, as well as indirect coupling, fixing, or attaching through one or more intermediate components or features, unless otherwise specified herein.

[0029] Except as explicitly indicated otherwise, recitation of a singular processing element (e.g., “a controller,”“a processor,”“a microprocessor,” etc.) is understood to include more than one processing element. In other words, “a processing element” is generally understood as “one or more processing element.” Furthermore, barring a specific statement to the contrary, any steps or functions recited as being performed by “the processing element” or “said processing element” are generally understood to be capable of being performed by “any one of the one or more processing elements.” Thus, a first step or function performed by “the processing element” may be performed by “any one of the one or more processing elements,” and a second step or function performed by “the processing element” may be performed by “any one of the one or more processing elements and not necessarily by the same one of the one or more processing elements by which the first step or function is performed.” Moreover, it is understood that recitation of “the processing element” or “said processing element” performing a plurality of steps or functions does not require that at least one discrete processing element be capable of performing each one of the plurality of steps or functions.

[0030] Referring now to the figures, example aspects of the present disclosure will be discussed in greater detail.

[0031] FIGS. 1 and 2 provide perspective views of a gas cooking appliance according to example embodiments of the present disclosure. Specifically, FIG. 1 provides a front, perspective view of gas cooking appliance 100 as may be employed with the present subject matter, while FIG. 2 provides a side cross-sectional view of gas cooking appliance 100. As shown in FIGS. 1 and 2, gas cooking appliance 100 of the present disclosure may be a range appliance, including both an oven and a cooktop. However, it should be appreciated that gas cooking appliance 100 is provided by way of example only, and aspects of the present subject matter may be used in any suitable gas cooking appliance, such as a gas oven, a gas cooktop, or a gas range appliance. Thus, the example embodiment shown in FIGS. 1 and 2 are not intended to limit the present subject matter to any particular cooking configuration or arrangement. Indeed, aspects of the present subject matter may be applied to gas heating elements of any suitable appliance.

[0032] Gas cooking appliance 100 generally defines a vertical direction V, a lateral direction L, and a transverse direction T, each of which is mutually perpendicular, such that an orthogonal coordinate system is generally defined. As illustrated, gas cooking appliance 100 includes an insulated cabinet 102. Cabinet 102 of gas cooking appliance 100 extends between a top 104 and a bottom 106 along the vertical direction V, between a first side 108 (left side when viewed from front) and a second side 110 (right side when viewed from front) along the lateral direction L, and between a front 112 and a rear 114 along the transverse direction T.

[0033] Within cabinet 102 is a cooking chamber 120 which is configured for the receipt of one or more food items to be cooked. Gas cooking appliance 100 is depicted in FIGS. 1 and 2 as a single oven range appliance with a single cooking chamber 120. However, those of ordinary skill in the art will understand that this is done by way of example only and gas cooking appliance 100 may include any number of cooking chambers 120. For example, gas cooking appliance 100 may be a double oven range appliance which includes two cooking chambers 120. Gas cooking appliance 100 includes a door 124 rotatably attached to cabinet 102 in order to permit selective access to cooking chamber 120. Handle 126 is mounted to door 124 to assist a user with opening and closing door 124 in order to access cooking chamber 120. For example, a user can pull on handle 126 mounted to door 124 to open or close door 124 and access cooking chamber 120. One or more transparent viewing windows 128 (FIG. 1) may be defined within door 124 to provide for viewing the contents of cooking chamber 120 when door 124 is closed and also assist with insulating cooking chamber 120.

[0034] As shown in FIG. 2, cooking chamber 120 is defined by a plurality of chamber walls 130. Specifically, cooking chamber 120 may be defined by a top wall, a rear wall, a bottom wall, and two side walls 130. These chamber walls 130 may be joined together to define an opening through which a user may selectively access cooking chamber 120 by opening door 124. In order to insulate cooking chamber 120, gas cooking appliance 100 includes an insulating gap defined between the chamber walls 130 and cabinet 102. According to an example embodiment, the insulation gap is filled with an insulating material 132, such as insulating foam or fiberglass, for insulating cooking chamber 120.

[0035] Gas cooking appliance 100 may also include a cooktop 140. Cooktop 140 is positioned at or adjacent top 104 of cabinet 102 such that it is positioned above cooking chamber 120. As shown in FIG. 1, cooktop 140 includes a top panel 142 positioned proximate top 104 of cabinet 102. By way of example, top panel 142 may be constructed of glass, ceramics, enameled steel, and combinations thereof. One or more grates 144 are supported on a top surface of top panel 142 for supporting cooking utensils, such as pots or pans, during a cooking process.

[0036] Gas cooking appliance 100 further includes one or more gas heating elements 150 for selectively heating cooking utensils positioned on grates 144 or food items positioned within cooking chamber 120. For example, as shown in FIG. 1, heating elements 150 may be gas burners 150. Specifically, a plurality of gas burners 150 may be mounted within or on top of top panel 142 underneath grates 144 that supports cooking utensils over the gas burners 150 while gas burners 150 provide thermal energy to cooking utensils positioned thereon, e.g., to heat food and / or cooking liquids (e.g., oil, water, etc.). Gas burners 150 can be configured in various sizes so as to provide e.g., 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 some embodiments, gas cooking appliance 100 may have other cooktop configurations or burner elements.

[0037] In addition, gas heating elements 150 may be positioned within or may otherwise be in thermal communication with cooking chamber 120 for regulating the temperature within cooking chamber 120. Specifically, an upper gas heating element 154 (also referred to as a broil heating element or gas burner) may be positioned in cabinet 102, e.g., at a top portion of cooking chamber 120, and a lower gas heating element 156 (also referred to as a bake heating element or gas burner) may be positioned at a bottom portion of cooking chamber 120. Upper gas heating element 154 and lower gas heating element 156 may be used independently or simultaneously to heat cooking chamber 120, perform a baking or broil operation, perform a cleaning cycle, etc. The size and heat output of gas heating elements 154, 156 can be selected based on, e.g., the size of gas cooking appliance 100 or the desired heat output. Gas cooking appliance 100 may include any other suitable number, type, and configuration of heating elements within cabinet 102 and / or on cooktop 140. For example, gas cooking appliance 100 may further include electric heating elements, induction heating elements, or any other suitable heat generating device.

[0038] As shown in FIG. 1, a control panel assembly 160 may be located within convenient reach of a user of the gas cooking appliance 100. For this example embodiment, control panel assembly 160 is positioned at a top 104 and front 112 of cabinet 102, e.g., above door 124 along the vertical direction V and forward of cooktop 140 along the transverse direction T. Control panel assembly 160 may include one or more user input devices (e.g., knobs 162, buttons 172). In some embodiments, knobs 162 may each be associated with a heating element 150 on cooktop 140. In addition, buttons 172 may be associated with heating elements 150 positioned within cooking chamber 120. For example, buttons 172 may allow the user to set cooking modes that automatically control heating elements 150 positioned within cooking chamber 120. In this manner, user input devices (e.g., knobs 162, buttons 172) may allow the user to activate each heating element 150 and determine the amount of heat input provided by each heating element 150 for cooking food items within cooking chamber 120 or on cooktop 140. Although shown with knobs 162 and buttons 172, it should be understood that user input devices and the configuration of gas cooking appliance 100 shown in FIG. 1 is provided by way of example only. More specifically, control panel assembly 160 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. Control panel assembly 160 may also be provided with one or more graphical display devices or display components, such as a digital or analog display device designed to provide operational feedback or other information to the user such as e.g., whether a particular heating element 150 is activated and / or the rate at which the heating element 150 is set. Indeed, according to the illustrated embodiment, control panel assembly 160 includes a display assembly 164, such as a liquid crystal display with an interactive display and interface.

[0039] Generally, gas cooking appliance 100 may include a control system 166 in operative communication with control panel assembly 160. Control panel assembly 160 of gas cooking appliance 100 may be in communication with control system 166 via, for example, one or more signal lines or shared communication busses, and signals generated in control system 166 may operate gas cooking appliance 100 in response to user input via user input devices, e.g., control knobs 162, buttons 172, and / or display assembly 164. Input / Output (“I / O”) signals may be routed between control system 166 and various operational components of gas cooking appliance 100 such that operation of gas cooking appliance 100 can be regulated by control system 166. In addition, control system 166 may also be in communication with one or more sensors, such as temperature sensor 168, which may be used to measure temperature inside cooking chamber 120 and provide such measurements to the control system 166. Although temperature sensor 168 is illustrated at a top and rear of cooking chamber 120, it should be appreciated that other sensor types, positions, and configurations may be used according to alternative embodiments.

[0040] Control system 166 includes a “processing device” or “controller” and may be embodied as described herein. Control system 166 may include a memory and one or more microprocessors, microcontrollers, application-specific integrated circuits (ASICS), CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of gas cooking appliance 100, and control system 166 is not restricted necessarily to a single element. The memory may represent random access memory such as DRAM, or read only memory such as ROM, electrically erasable, programmable read only memory (EEPROM), or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. Alternatively, control system 166 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.

[0041] Although aspects of the present subject matter are described herein in the context of a single oven appliance, it should be appreciated that gas cooking appliance 100 is provided by way of example only. Other oven or range appliances having different configurations, different appearances, and / or different features may also be utilized with the present subject matter, e.g., double ovens, connected oven / cooktop units, etc. Moreover, aspects of the present subject matter are equally applicable to standalone cooktops (e.g., without cooking chambers) or other cooking appliances.

[0042] In general, gas cooking appliance 100 may include a fuel supply system 180 configured for selectively supplying gaseous fuel (e.g., gas) such as propane, natural gas, liquefied petroleum (LP), butane, or any other suitable fuel to heating elements 150. Fuel supply system 180 may include a pressurized gaseous fuel source (not shown), such as a natural gas supply line, a propane tank, etc. In this manner, a flow of supply fuel, such as gaseous fuel (e.g., natural gas or propane), is flowable from the fuel supply system 180 to heating elements 150. Fuel supply system 180 may further include a control valve or fuel regulating device operably coupling a gaseous fuel source to one or more heating elements 150.

[0043] Specifically, the fuel regulating device may be a three-way, solenoid-controlled valve or bimetal valve for selectively directing a metered amount of fuel to upper gas heating element 154 and lower gas heating element 156. More specifically, according to an example embodiment, a user input device of control panel assembly 160, such as a button 172 (FIG. 1), may be operably coupled to fuel supply system 180 for regulating the flow of supply fuel. In this regard, a user may press a button 172 (FIG. 1) to set a cooking mode, automatically adjusting the flow of supply fuel from the gaseous fuel source to both upper gas heating element 154 and lower gas heating element 156.

[0044] Referring now specifically to FIG. 2, an example gas ignition system 200 of gas cooking appliance 100 is provided according to example embodiments of the present disclosure. Gas ignition system 200 includes one or more ignition components 190 operable to ignite gas (e.g., gaseous fuel).

[0045] Ignition components 190 may be operably coupled to each gas heating element 150 for igniting the flow of fuel as it passes into gas heating element 150. Specifically, according to the illustrated embodiment, each ignition component 190 may be a hot surface igniter (HSI), e.g., such as a silicon carbide, silicon nitride, or any other suitable hot surface igniter for use with a gas heating element 150. In some embodiments, ignition components 190 may be positive temperature coefficient (PTC) hot surface igniter (HSI). For example, as the temperature of the HSI rises, a resistance associated with the HSI may rise. As shown, ignition components 190 may be positioned within a cooking chamber 120 of gas cooking appliance 100. For instance, an ignition component 190 may positioned proximate a rear of each of upper gas heating element 154 and lower gas heating element 156, (e.g., at the entrance where the flow of fuel was provided into the respective heating elements 154, 156).

[0046] Gas ignition system 200 may further include one or more gas valves 192 configured to provide gas to the one or more ignition components 190. As shown, gas valves 192 are electrically controlled gas valves that may be controlled (e.g., opened or closed) with an electrical signal, such as an enable signal. For example, gas valves 192 may be solenoid valves.

[0047] Fuel supply lines may fluidly couple each gas valve 192 to fuel supply system 180 (e.g., gas source of gas distribution system 180) to receive gas. Although gas valves 192 depicted in FIG. 2 are illustrated as being dedicated valves separate from fuel supply system 180, it should be appreciated that according to alternative embodiments, a single gas valve 192 may be used to control the flows of fuel to each gas heating element 150 (e.g., both upper gas heating element 154 and lower gas heating element 156). However, as shown in FIG. 2, each gas valve 192 may correspond to an ignition component 190. For example, gas ignition system 200 may include one or more ignition components 190 and one or more gas valves 192 corresponding to the one or more ignition components 190. While gas ignition system 200 of FIG. 2 is depicted with two ignition components 190 and two corresponding gas valves 192, those of ordinary skill in the art will understand that gas ignition system 200 may include any suitable number of ignition components 190 and / or gas valves 192 without deviating from the scope of the present disclosure.

[0048] As explained briefly above, gas ignition system 200 is configured to provide proof that an ignition component is capable of igniting gas. As such, gas ignition system 200 (e.g., through gas valves 192) may control the flow of fuel to ignition components 190. For example, the flow of fuel may typically ignite when ignition component 190 (e.g., HSI) reaches an ignition temperature (e.g., predetermined threshold temperature) which indicates a sufficient temperature of the HSI for igniting the flow of fuel. In order to prevent the flow of fuel into gas heating elements 150 prior to ignition component 190 reaching the ignition temperature, gas valve 192 is configured to provide gas (e.g., fuel) to the ignition component 190 based at least in part on an enable signal indicating that the ignition component 190 is at or above the ignition temperature.

[0049] As such, gas ignition system 200 further includes ignition controller 400 configured to provide the enable signal. As shown in FIG. 2, ignition controller 400 may be operably coupled to ignition components 190 and corresponding gas valves 192. Ignition controller 400 may receive a feedback signal indicative of a temperature of the ignition component 190 (e.g., HSI). In some embodiments, the feedback signal may be provided to controller 400 by an ignition sensor such as a shunt resistor. Controller 400 is configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times. Specifically, controller 400 may provide the enable signal to a gas valve 192 associated with ignition component 190 to control the gas valve 192 to provide gas to the ignition component 190.

[0050] In some embodiments, ignition controller 400 may be a sub-system of control system 166 such that ignition controller 400 is operatively coupled to control system 166. Accordingly, in some embodiments, ignition controller 400 may be positioned in control panel assembly 160 (FIG. 1). As such, ignition components 190 may be activated and deactivated by control system 166 to facilitate the igniting and extinguishing processes, respectively, of a gas burner 150. Specifically, for example, control system 166 may regulate a position of an igniter relay (not shown) which may be closed to energize ignition component 190, thereby causing ignition component 190 to heat up and ignite the flow of fuel. By contrast, control system 166 may open the igniter relay to permit ignition component 190 cool below temperature at which the flow of fuel may be stopped (e.g., by gas valve 192) and the flame may be extinguished.

[0051] In some embodiments, gas valve 192 may be a safety valve that is positioned along a fuel supply line between fuel supply system 180 and an ignition component 190. Gas valve 192 may remain in the closed position until the enable signal is provided to the gas valve 192. When the enable signal is provided, gas valve 192 may be opened to permit the flow of fuel from the fuel supply system 180 to the ignition component 190 corresponding to the gas valve 192. When ignition component 190 drops below the ignition temperature after a heating cycle, gas valve 192 may be closed again to prevent the flow of fuel.

[0052] In some embodiments, gas valve 192 may be electrically connected to ignition component 190 in a manner suitable for providing the feedback signal. For example, ignition controller 400 may receive the feedback signal indicating the temperature of ignition component 190 via gas valve 192.

[0053] Referring now to FIG. 3, a circuit schematic of an example gas ignition system 300 is provided according to example embodiments of the present disclosure. Gas ignition system 300 may be configured to provide gas to an ignition component 190 that is capable of igniting gaseous fuel. Accordingly, gas ignition system 300 may also determine if the ignition component 190 is capable of igniting gas based at least in part on a feedback signal 302. Gas ignition system 300 may be implemented in a gas cooking appliance, such as gas cooking appliance 100 as shown in FIGS. 1 and 2. While gas ignition system 300 of FIG. 3 is described with reference to gas cooking appliance 100, those of ordinary skill in the art will understand that gas ignition system 300 may be used in any suitable appliance or system.

[0054] Gas ignition system 300 includes one or more ignition components 190. Ignition component 190 may be activated and deactivated by the opening and closing of a position on an igniter relay 194. Specifically, a switch corresponding to an ignition component 190 may be closed to energize ignition component 190, causing the ignition component 190 to heat up in order to ignite the flow of fuel. In some embodiments, igniter relay 194 may be a component of a machine control for a gas cooking appliance. In some embodiments, igniter relay may be controlled by a control system of a gas cooking appliance, such as control system 166 depicted in FIGS. 1 and 2. In some embodiments, igniter relay 194 may activate (e.g., apply power to) an ignition component 190 when a user selects a cycle.

[0055] As shown in FIG. 3, an ignition component 190 may be represented as a variable resistor. As previously described, each ignition component 190 may be a hot surface igniter (HSI), such as a positive temperature coefficient (PTC) HSI 190 operable to ignite gas at an ignition temperature. An ignition sensor 310 is configured to provide a feedback signal 302 indicative of a temperature of ignition component 190. As shown, ignition sensor 310 may be a shunt sensor (e.g., shunt resistor) electrically coupled to the ignition component 190.

[0056] As such, a feedback signal 302 may indicate a shunt voltage level of an alternating current supplied to the ignition component 190. Accordingly, the shunt voltage measured by the feedback signal 302 may decrease as the temperature of the HSI increases (e.g., heats up). For instance, the resistance of ignition component 190 (e.g., PTC HSI) may increase as the temperature of ignition component 190 increases.

[0057] Ignition sensor 310 may also be electrically coupled to an ignition controller 400, such that feedback signal 302 may be provided to the ignition controller 400. Ignition controller 400 may be configured to determine a plurality of samples of a feedback signal 302, each sample associated with one of a plurality of different times. Accordingly, ignition controller 400 may provide an enable signal 320 based at least in part on the plurality of feedback samples indictive of the feedback signal.

[0058] As shown in FIG. 3, enable signals 320 may be provided to a switching device (e.g., MOSFET), allowing VCC to be applied to a solenoid switch of a gas valve 192. Specifically, ignition controller 400 may provide enable signal 320 when the temperature of the ignition component 190 (e.g., HSI, PTC HSI) is at or above an ignition temperature of the HSI.

[0059] In some embodiments, gas ignition system 300 may include additional circuitry or hardware components. For instance, an input connector 408 may be electrically coupled to ignition controller 400 and ignition components 190. In addition, an output connector 191 may be configured to provide VCC to gas valves 192 based at least in part on an enable signal provided to switching devices 360.

[0060] In some embodiments, ignition controller 400 may receive power signal 412 from power supply 410 (e.g., offline switch-mode power supply). Power supply 410 may further provide neutral signal 414 to ignition controller 400. As shown in FIG. 3, neutral signal 414 may be provided from ignition relay 194. In some embodiments, power supply 410 is configured to supply power to ignition controller 400 when there is an active call for heat.

[0061] For instance, a call for heat signal 304 may be provided to ignition controller 400 from ignition relay 194 (e.g., via input connector 408). The call for heat signal may be represented by voltage signals from ignition relay 194. Call for heat signal 304 may be used to indicate that a gas valve 192 corresponds to the ignition component 190 that provides feedback signal 302. Specifically, call for heat signal 304 may be defined as an active voltage to both HSI 190 as well as the ignition controller 400. For example, one or more HSIs 190 may be activated to heat a cavity of a gas cooking appliance to a desired temperature during a cooking cycle selected by a user. Accordingly, power may be cycled to the one or more HSIs 190 for the cavity to remain at the desired temperature. In some embodiments, gas ignition system 300 may not be configured to hold in memory the current cycle selected by a user and may only be powered on when there is an active call for heat. Accordingly, ignition controller 400 may provide proof that the one or more HSIs 190 (e.g., ignition components 190) are capable of igniting a gaseous fuel multiple times each cooking cycle. As such, gas ignition system 300 may include a stand alone system (e.g., ignition system 350) configured to confirm that one or more ignition components 190 (e.g., one or more HSIs 190) are electrically capable of igniting gaseous fuel such that gas valves 192 corresponding to the ignition components may be controlled electronically.

[0062] While gas ignition system 300 of FIG. 3 is depicted with two ignition components 190 and two corresponding gas valves 192, those of ordinary skill in the art will understand that gas ignition system 300 may include any suitable number of ignition components 190 and / or gas valves 192 without deviating from the scope of the present disclosure.

[0063] Referring now to FIG. 4, a block diagram depicting internal logic of an example ignition controller 400 is provided. Ignition controller 400 may be configured to provide an enable signal 420 based at least in part on a feedback signal 402 indicative of a temperature of an ignition component (e.g., HSI, PTC HSI).

[0064] As shown in FIG. 4, a feedback signal 402 may be an input to comparator components 438 (e.g., comparators). In some embodiments, comparator components 438 may compare feedback signal 402 to a threshold indicative of an ignition temperature of the ignition component. comparator components 438 may provide the feedback signal 402 to latch component 440.

[0065] Ignition controller 400 may further receive a call for heat signal 404. In some embodiments, call for heat signal 404 may be a periodic electrical signal indicating the zero cross of the feedback signal 402. Latch component 440 may determine a first feedback sample at a time call for heat signal 404 is received, such that the first feedback sample may be determined at a first time corresponding to a zero cross of the feedback signal 402. Latch component 440 may further determine second and third feedback samples at times after the first feedback sample is determined. For instance, delay components 442, 444 may provide delays, such that second and third feedback samples may be determined at times after the first time. For instance, delay component 442 may provide a signal to latch component 440 at a second time, such as 1 millisecond (ms) after the first time. In addition, delay component 444 may provide a signal to latch component 440 at a third time corresponding to a peak (e.g., period of π / 2 radians) of the feedback signal 402 after the zero cross.

[0066] If the plurality of feedback samples indicate that the temperature of the ignition component is at or above the ignition temperature of the ignition component, ignition controller 400 may provide an enable signal 420 to allow gas to be provided to the ignition component.

[0067] In some embodiments, ignition controller 400 may include additional circuitry / logic. For instance, latch component 440 may interface a timing block 446 configured to determine that a singular boosting valve is present. In addition, timing block 446 may interface boost and hold circuitry 448, 450 and output circuitry 452 to, for instance, provide enable signal 420 as a pulse width modulated (PWM) signal.

[0068] In some embodiments, ignition controller 400 may include a watch dog component 454 to determine that the ignition controller 400 is not operating in a fault state. For instance, watch dog component 454 may receive a signal indicating call for heat signal 404 as well as interface latch component 440 and comparator components 438. If the watch dog component 454 determines that ignition controller 400 is operating in a fault state, watch dog component 454 may initiate an internal reset.

[0069] In some embodiments, ignition controller 400 may be defined as an Integrated Circuit (IC) controller, such as a Configurable Mixed-Signal Integrated Circuit (CMIC) device. For instance, hardware configured to perform the logic components of ignition controller 400 depicted in FIG. 4 may be positioned within a singular controller package 405 of ignition controller 400.

[0070] FIG. 5 provides an example feedback signal 510 according to example embodiments of the present disclosure. Feedback signal 510 may be indicative of a temperature of an ignition component (e.g., HSI, PTC HSI), such as ignition component 190 previously described. Specifically, feedback signal 510 may indicate a shunt voltage level as read by an ignition sensor, such as shunt sensor 310 depicted in FIG. 3. As shown, the voltage of feedback signal 510 may indicate the temperature of an ignition component. For instance, the voltage of feedback signal 510 may decrease as the ignition component heats up over time.

[0071] FIG. 5 depicts the positive polarity of feedback signal 510 for purposes of illustration and discussion. As such, those of ordinary skill in the art will understand that feedback signal 510 may be a periodic alternating signal switching from a positive polarity to a negative polarity at, for instance, regularly reoccurring intervals. Specifically, FIG. 5 may depict feedback signal 510 over a first time period 512, a second time period 514, and a third time period 516. Each time period 512, 514, 516 may correspond to the positive polarity of feedback signal 510 over time as the ignition component heats up. For instance, each period 512, 514, 516 may depict the feedback signal 510 from a zero cross (e.g., negative to positive) to a zero cross (e.g., positive to negative). Accordingly, each time period 512, 514, 516 may be represented in radians with each period 512, 514, 516 spanning from 0 radians to π radians (e.g., a half cycle of feedback signal 510).

[0072] An ignition controller, such as ignition controller 400 depicted in FIGS. 2-4, may determine a plurality of feedback samples indicative of feedback signal 510 during each time period 512, 514, 516. For instance, referring specifically to the first time period 512, a first feedback sample may be determined (e.g., measured) at a first time (t1). As shown, the first time (t1) may correspond with a zero cross of the feedback signal 510 (e.g., 0 radians). A second feedback sample may be measured at a second time (t2) after the zero cross at the first time (t1). The second time (t2) may correspond to a phase of the feedback signal 510 after the first time (t1), such as at π / 8 radians. A third feedback sample may be measured at a third time (t3) corresponding to a peak (e.g., phase of π / 2 radians) of the feedback signal after the first time (t1) and the second time (t2).

[0073] Similarly, during the second time period 514, a first feedback sample may be determined (e.g., measured) at a first time (t4). As shown, the first time (t4) may correspond with another zero cross of the feedback signal 510 (e.g., 0 radians). A second feedback sample may be measured at a second time (t5) after the zero cross at the first time (t4). The second time (t5) may correspond to a phase of the feedback signal 510 after the first time (t4), such as at π / 8 radians. A third feedback sample may be measured at a third time (t6) corresponding to a peak (e.g., phase of π / 2 radians) of the feedback signal after the first time (t4) and the second time (t5).

[0074] During the third time period 516, a first feedback sample may be determined (e.g., measured) at a first time (t7). As shown, the first time (t7) may correspond with yet another zero cross of the feedback signal 510 (e.g., 0 radians). A second feedback sample may be measured at a second time (t8) after the zero cross at the first time (t7). The second time (t8) may correspond to a phase of the feedback signal 510 after the first time (t7), such as at π / 8 radians. A third feedback sample may be measured at a third time (t9) corresponding to a peak (e.g., phase of π / 2 radians) of the feedback signal after the first time (t7) and second time (t8).

[0075] As previously described, an ignition controller such as ignition controller 400 (FIGS. 2-4) may provide an enable signal based at least in part on the plurality of feedback samples. Specifically, the ignition controller 400 (FIGS. 2-4) may provide the enable signal based at least in part on a comparison of the plurality of feedback samples to a threshold value. As shown in FIG. 5, the plurality of feedback samples may be compared to a threshold value 520 indicating, for instance, a reference voltage. Specifically, the enable signal may be provided when the first feedback sample and the second feedback sample are below the threshold value 520 and the third feedback sample is above the threshold value 520.

[0076] For instance, an enable signal may not be provided based on the feedback signal 510 over the first time period 512 as the first feedback sample at the first time (t1) is below the threshold value 520 while the second feedback sample at the second time (t2) and third feedback sample at the third time (t3) are above the threshold value 520. Similarly, an enable signal may not be provided based on the feedback signal 510 over the second time period 514 as the first feedback sample at the first time (t4) is below the threshold value 520 while the second feedback sample at the second time (t5) and third feedback sample at the third time (t6) are above the threshold value 520.

[0077] However, an enable signal may be provided based on the feedback signal 510 over the third time period 516 as the first feedback sample at the first time (t7) and the second feedback sample at the second time (t8) are below the threshold value 520 while the third feedback sample at the third time (t9) is above the threshold value 520. As such, the feedback signal 510 over the third time period 516 may indicate that the temperature of the ignition component (e.g., HSI, PTC HSI) is at or above an ignition temperature of the ignition component.

[0078] FIG. 6 provides a flowchart of an example method 600 for providing gas to an ignition component of a gas cooking appliance according to example embodiments of the present disclosure. While method 600 is described with reference to gas cooking appliance 100, gas ignition system 300, and ignition controller 400, those of ordinary skill in the art will understand that method 600 may be implemented in any suitable gas cooking system.

[0079] At 610, method 600 includes receiving, from an ignition sensor, a feedback signal indicative of a temperature of the ignition component. For instance, ignition sensor 310 may provide a feedback signal indicative of a temperature of an ignition component 190. The ignition component 190 may be a hot surface igniter (HSI), such as a positive temperature coefficient (PTC) hot surface igniter (HSI).

[0080] At 620, method 600 includes determining a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

[0081] At 630, method 600 includes providing, by an ignition controller, an enable signal based at least in part on the plurality of feedback samples. For instance, ignition controller 400 may provide an enable signal based at least in part on the plurality of feedback samples.

[0082] At 640, method 600 includes providing gas to the ignition component based at least in part on the enable signal. For instance, ignition system 300 may provide gas to the ignition component 190 based at least in part on the enable signal.

[0083] One example aspect of the present disclosure is directed to a gas ignition system for a gas cooking appliance. The gas ignition system includes an ignition component operable to ignite gas based at least in part on an enable signal. The gas ignition system further includes an ignition sensor configured to provide a feedback signal indicative of a temperature of the ignition component. The gas ignition system further includes an ignition controller configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

[0084] In some examples, the ignition controller is configured to provide the enable signal based at least in part on a comparison of the plurality of feedback samples to a threshold value.

[0085] In some examples, the plurality of feedback samples includes a first feedback sample measured at a first time, a second feedback sample measured at a second time after the first time, and a third feedback sample measured at a third time after the second time.

[0086] In some examples, the first time corresponds to a zero cross of the feedback signal.

[0087] In some examples, the third time corresponds to a peak of the feedback signal.

[0088] In some examples, the ignition controller is configured to provide the enable signal when the first feedback sample and the second feedback sample are below the threshold value and the third feedback sample is above the threshold value.

[0089] In some examples, the ignition component is a positive temperature coefficient (PTC) hot surface igniter (HSI).

[0090] In some examples, the ignition controller is configured to provide the enable signal when the temperature of the PTC HSI is at or above an ignition temperature of the PTC HSI.

[0091] In some examples, the gas ignition system further includes a gas valve configured to provide gas to the ignition component based at least in part on the enable signal provided by the ignition controller.

[0092] Another example aspect of the present disclosure is directed to method for providing gas to an ignition component of a gas cooking appliance. The method includes receiving, from an ignition sensor, a feedback signal indicative of a temperature of the ignition component. The method further includes determining a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times. The method further includes providing, by an ignition controller, an enable signal based at least in part on the plurality of feedback samples. The method further includes providing gas to the ignition component based at least in part on the enable signal.

[0093] In some examples, the enable signal is provided based at least in part on a comparison of the plurality of feedback samples to a threshold value.

[0094] In some examples, the plurality of feedback samples includes a first feedback sample measured at a first time, a second feedback sample measured at a second time after the first time, and a third feedback sample measured at a third time after the second time.

[0095] In some examples, the first time corresponds to a zero cross of the feedback signal.

[0096] In some examples, the third time corresponds to a peak of the feedback signal.

[0097] In some examples, the ignition component is a positive temperature coefficient (PTC) hot surface igniter (HSI).

[0098] In some examples, the ignition controller is configured to provide the enable signal when the temperature of the PTC HSI is at or above an ignition temperature of the PTC HSI.

[0099] Another example aspect of the present disclosure is directed to a gas cooking appliance. The gas cooking appliance includes a cooking chamber. The gas cooking appliance further includes an ignition component operable to ignite gas based at least in part on an enable signal. The gas cooking appliance further includes an ignition sensor configured to provide a feedback signal indicative of a temperature of the ignition component. The gas cooking appliance further includes an ignition controller configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

[0100] In some examples, the ignition component is associated with the cooking chamber.

[0101] In some examples, the ignition controller is configured to provide the enable signal based at least in part on a comparison of the plurality of feedback samples to a threshold value.

[0102] In some examples, the gas cooking appliance further includes a solenoid switch configured to receive the enable signal, and a gas valve configured to provide gas to the ignition component based at least in part on the enable signal received by the solenoid switch.

[0103] Although specific features of various embodiments may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the present disclosure, any feature of a drawing can be referenced and / or claimed in combination with any feature of any other drawing.

[0104] While the present subject matter has been described in detail with respect to specific example embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing can readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and / or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art.

Claims

1. A gas ignition system for a gas cooking appliance, comprising:an ignition component operable to ignite gas based at least in part on an enable signal;an ignition sensor configured to provide a feedback signal indicative of a temperature of the ignition component; andan ignition controller configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

2. The gas ignition system of claim 1, wherein the ignition controller is configured to provide the enable signal based at least in part on a comparison of the plurality of feedback samples to a threshold value.

3. The gas ignition system of claim 2, wherein the plurality of feedback samples comprises:a first feedback sample measured at a first time;a second feedback sample measured at a second time after the first time; anda third feedback sample measured at a third time after the second time.

4. The gas ignition system of claim 3, wherein the first time corresponds to a zero cross of the feedback signal.

5. The gas ignition system of claim 4, wherein the third time corresponds to a peak of the feedback signal.

6. The gas ignition system of claim 3, wherein the ignition controller is configured to provide the enable signal when the first feedback sample and the second feedback sample are below the threshold value and the third feedback sample is above the threshold value.

7. The gas ignition system of claim 1, wherein the ignition component is a positive temperature coefficient (PTC) hot surface igniter (HSI).

8. The gas ignition system of claim 7, wherein the ignition controller is configured to provide the enable signal when the temperature of the PTC HSI is at or above an ignition temperature of the PTC HSI.

9. The gas ignition system of claim 1, further comprising a gas valve configured to provide gas to the ignition component based at least in part on the enable signal provided by the ignition controller.

10. A method for providing gas to an ignition component of a gas cooking appliance, comprising:receiving, from an ignition sensor, a feedback signal indicative of a temperature of the ignition component;determining a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times;providing, by an ignition controller, an enable signal based at least in part on the plurality of feedback samples; andproviding gas to the ignition component based at least in part on the enable signal.

11. The method of claim 10, wherein the enable signal is provided based at least in part on a comparison of the plurality of feedback samples to a threshold value.

12. The method of claim 10, wherein the plurality of feedback samples comprises:a first feedback sample measured at a first time;a second feedback sample measured at a second time after the first time; anda third feedback sample measured at a third time after the second time.

13. The method of claim 12, wherein the first time corresponds to a zero cross of the feedback signal.

14. The method of claim 13, wherein the third time corresponds to a peak of the feedback signal.

15. The method of claim 10, wherein the ignition component is a positive temperature coefficient (PTC) hot surface igniter (HSI).

16. The method of claim 15, wherein the ignition controller is configured to provide the enable signal when the temperature of the PTC HSI is at or above an ignition temperature of the PTC HSI.

17. A gas cooking appliance, comprising:a cooking chamber;an ignition component operable to ignite gas based at least in part on an enable signal;an ignition sensor configured to provide a feedback signal indicative of a temperature of the ignition component; andan ignition controller configured to provide the enable signal based at least in part on a plurality of feedback samples indicative of the feedback signal, each sample associated with one of a plurality of different times.

18. The gas cooking appliance of claim 17, wherein the ignition component is associated with the cooking chamber.

19. The gas cooking appliance of claim 18, wherein the ignition controller is configured to provide the enable signal based at least in part on a comparison of the plurality of feedback samples to a threshold value.

20. The gas cooking appliance of claim 17, further comprising:a solenoid switch configured to receive the enable signal; anda gas valve configured to provide gas to the ignition component based at least in part on the enable signal received by the solenoid switch.

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