The present subject matter relates generally to cooktop appliances, including cooktop appliances configured for precise temperature control.
Cooktop appliances generally include heating elements for heating cooking utensils, such as pots, pans and griddles. A user can select a desired heating level, and operation of one or more of the heating elements is modified to match the desired heating level. For example, certain cooktop appliances include electric heating elements. During operation, the cooktop appliance operates the electric heating elements at a predetermined power output corresponding to a selected heating level. As another example, some cooktop appliances include gas burners as heating elements. During operation, the heat output of the gas burner is modulated by adjusting a position of a control valve coupled to the gas burner.
Some cooktop appliances are operable in a precision mode, which generally uses a closed-loop control algorithm to vary the output of the heating element in response to the desired heating level and a measured temperature, e.g., of or at the cooking utensil. Typical closed-loop control algorithms are generally based on certain assumptions which are suitable for most, but not all, cooking tasks. In cases were these assumptions are not applicable, such as sauce reduction, the typical closed-loop algorithm may not produce the desired results.
Accordingly, a cooktop appliance with features for improved precision temperature control, e.g., that is specifically attuned for automatic sauce reduction, would be useful.
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 one example embodiment, a cooktop appliance includes a user interface. The cooktop appliance also includes a heating element positioned at a cooking surface of the cooktop appliance and a temperature sensor configured to measure a temperature at a utensil heated by the heating element. The cooktop appliance further includes a controller. The controller is configured for receiving a sauce reduction mode initiation signal. The controller is also configured for operating the heating element at a first power level during a preheat stage and for operating the heating element at a second power level during a reduction stage after the preheat stage. The second power level is less than the first power level. The controller is further configured for determining that the reduction stage has ended and deactivating the heating element because the reduction stage has ended. The controller is also configured for providing a user notification that the sauce reduction mode is complete after deactivating the heating element.
In another example embodiment, a method of operating a cooktop appliance is provided. The cooktop appliance includes a user interface, a heating element positioned at a cooking surface of the cooktop appliance, and a temperature sensor configured to measure a temperature at a utensil heated by the heating element. The method includes receiving a sauce reduction mode initiation signal. The method also includes operating the heating element at a first power level during a preheat stage and operating the heating element at a second power level during a reduction stage after the preheat stage. The second power level is less than the first power level. The method further includes determining that the reduction stage has ended and deactivating the heating element because the reduction stage has ended. The method also includes providing a user notification that the sauce reduction mode is complete after deactivating the heating element.
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.
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.
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.
Upper and lower cooking chambers 120 and 122 are configured for the receipt of one or more food items to be cooked. Cooktop appliance 100 includes an upper door 124 and a lower door 126 rotatably attached to cabinet 110 in order to permit selective access to upper cooking chamber 120 and lower cooking chamber 122, respectively. Handles 128 are mounted to upper and lower doors 124 and 126 to assist a user with opening and closing doors 124 and 126 in order to access cooking chambers 120 and 122. As an example, a user can pull on handle 128 mounted to upper door 124 to open or close upper door 124 and access upper cooking chamber 120. Glass window panes 130 provide for viewing the contents of upper and lower cooking chambers 120 and 122 when doors 124 and 126 are closed and also assist with insulating upper and lower cooking chambers 120 and 122. Heating elements (not shown), such as electric resistance heating elements, gas burners, microwave heating elements, halogen heating elements, or suitable combinations thereof, are positioned within upper cooking chamber 120 and lower cooking chamber 122 for heating upper cooking chamber 120 and lower cooking chamber 122.
Cooktop appliance 100 also includes a cooktop 140. Cooktop 140 is positioned at or adjacent to a top portion of cabinet 110. Thus, cooktop 140 is positioned above upper and lower cooking chambers 120 and 122. Cooktop 140 includes a top panel 142. By way of example, top panel 142 may be constructed of glass, ceramics, stainless steel, enameled steel, and combinations thereof.
For cooktop appliance 100, a utensil 18 (see, e.g.,
A user interface panel 154 is located within convenient reach of a user of the range appliance 100. For this example embodiment, range appliance 100 also includes knobs 156 that are each associated with one of burner assemblies 144, 146, 148, 150 and griddle burner 160. Knobs 156 allow the user to activate each burner assembly and determine the amount of heat input provided by each burner assembly 144, 146, 148, 150 and griddle burner 160 to a cooking utensil located thereon. The user interface panel 154 may also include one or more inputs 157, such as buttons or a touch pad, for selecting or adjusting operation of the range appliance 100, such as for selecting or initiating a precision cooking mode, as will be described in more detail below. User interface panel 154 may also be provided with one or more graphical display devices 155 that deliver certain information to the user such as e.g., whether a particular burner assembly is activated and/or the temperature at which the burner assembly is set.
Although shown with knobs 156, it should be understood that knobs 156 and the configuration of range appliance 100 shown in
As will be discussed in greater detail below, the cooktop appliance 100 includes a control system 50 (
Referring now to
In some example embodiments, the cookware temperature sensor 28 may be in contact with, attached to, or integrated into the cooking utensil 18 and configured to sense a temperature of, e.g., a bottom surface of the cooking utensil 18 or bottom wall of the cooking utensil 18. For example, the cookware temperature sensor 28 may be embedded within the bottom wall of the cooking utensil 18 as illustrated in
Additionally, the food temperature sensor 30 may be positioned at any suitable location to sense a temperature of one or more food items 32 (see
In certain exemplary embodiments, one or both of the cookware temperature sensor 28 and the food temperature sensor 30 may utilize any suitable technology for sensing/determining a temperature of the cooking utensil 18 and/or food items 32 positioned in the cooking utensil 18. The cookware temperature sensor 28 and the food temperature sensor 30 may measure a respective temperature by contact and/or non-contact methods. For example, one or both of the cookware temperature sensor 28 and the food temperature sensor 30 may utilize one or more thermocouples, thermistors, optical temperature sensors, infrared temperature sensors, resistance temperature detectors (RTD), etc.
Referring again to
As stated, the cooktop appliance 100 includes a receiver 34 associated with one or more of the heating elements 16, for example a plurality of receivers 34 each associated with a respective heating element 16. For the embodiment depicted, each receiver 34 is positioned directly below a center portion of a respective heating element 16. Moreover, for the embodiment depicted, each receiver 34 is configured as a wireless receiver 34 configured to receive one or more wireless signals. Specifically, for the exemplary control system 50 depicted, both of the cookware temperature sensor 28 and the food temperature sensor 30 are configured as wireless sensors in wireless communication with the wireless receiver 34 via a wireless communications network 54. In certain exemplary embodiments, the wireless communications network 54 may be a wireless sensor network (such as a Bluetooth communication network), a wireless local area network (WLAN), a point-to point communication networks (such as radio frequency identification (RFID) networks, near field communications networks, etc.), a combination of two or more of the above communications networks, or any suitable wireless communications network or networks.
Referring still to
Referring again to
Further, the controller 52 is operably connected to each of the plurality of heating elements 16 for controlling an operating level, such as a supply of power or a flow of fuel, to each of the plurality of heating elements 16 in response to one or more user inputs through the user interface 62 (e.g., user interface panel 154 and/or controls, e.g., knobs 156). For example, the controller 52 may be operably connected to each of the plurality of heating elements 16 via a plurality of control devices 64, e.g., the controller 52 may be operably connected to the plurality of control devices 64, and each control device 64 may be associated with a respective one of the heating elements 16. In embodiments wherein one or more of the heating elements 16 are configured as electric resistance heaters, the controller 52 may be operably connected to respective relays, triodes for alternating current, or other devices for controlling an amount of power supplied to such electrical resistance heaters, each of which is an exemplary embodiment of control devices 64. Alternatively, in embodiments where one or more of the heating elements 16 are configured as induction heating elements, the controller 52 may be operably connected to respective current control devices, e.g., the control devices 64 operably connected to controller 52 may be respective current control devices for each induction heating element. As another example, in embodiments wherein one or more of the heating elements 16 are configured as gas burners, the control devices 64 may include one or more gas supply valves fluidly coupled to each gas burner for selectively adjusting or restricting, e.g., cutting off, a flow of fuel to each gas burner from a fuel supply.
In some embodiments, e.g., as illustrated in
As mentioned above, in some embodiments a cookware temperature sensor may be attached to or integrated within the cooking surface 158 of the cooktop appliance 100, such as integrated into one or more of the heating elements 16. One example of such embodiments is illustrated in
As mentioned above, the temperature sensor or sensors may be communicatively coupled with the controller 52 by a wired or wireless connection. For example, in the illustrated embodiment of
According to various embodiments of the present disclosure, the cooktop appliance 100 may be configured for a precision cooking mode and/or methods of operating the cooktop appliance 100 may include a precision cooking mode. In particular, as will be described in further detail below with reference to
When the closed loop control system is activated, controller 52 receives the temperature measurements from temperature sensor 28, 30, and/or 40 and compares the temperature measurements to a target temperature, e.g., the user-defined set temperature or a predetermined target temperature based on a current stage of the sauce reduction mode and/or based on the selected sauce attribute, e.g., type, quantity, volume, thickness, etc. In order to reduce a difference between the temperature measurements from the temperature sensor(s) and the target temperature, controller 52 adjusts the respective control device 64. Thus, the heat output provided by the heating element 16 may be regulated by the closed loop control system, e.g., without additional user input and/or monitoring.
A user may establish the set temperature and/or select a sauce attribute via the user interface 62, e.g., the user interface may include knobs 156, inputs 157, and a display 155, as in the illustrated example embodiment of
In some example embodiments, user interface 62 is positioned on top panel 142 and may be in communication with controller 52 via a wiring harness. As another example, user interface 62 may also or instead correspond to an application on a smartphone or other device, and the user may utilize the application, e.g., to establish the set temperature or select the sauce attribute. In such example embodiments, user interface 62 may be in wireless communication with controller 52, e.g., via a Bluetooth® or Wi-Fi® connection.
Turning now to
As mentioned above, the sauce reduction mode may be a precision cooking mode which is particularly suited for reducing a sauce, e.g., according to one or more of the further exemplary steps described hereinbelow. For example, the sauce reduction mode may generally include a preheat stage, during which the heating element is operated at a high power level in order to quickly reach a boil, followed by a reduction stage, wherein the element is operated at a lower power level in order to avoid burning the sauce while the sauce thickens during the reduction stage. In some embodiments, the reduction stage may be followed by an optional resting stage, during which the heating element is deactivated and the sauce is allowed to rest, whereby the sauce cools and thickens to a serving temperature and serving consistency during the resting stage. The power levels at which the heating element is operated during the foregoing stages, e.g., the preheat stage and the reduction stage, may be determined using a closed-loop control, may be fixed and predefined power levels, or may include combinations thereof. Further, the transitions between stages, e.g., the end of the preheat stage and the beginning of the reduction stage, the end of the reduction stage and the beginning of the resting stage, and/or the end of the resting stage, may be determined based on temperature (e.g., measured with one or more temperature sensors such as the exemplary sensors described herein) and/or time.
The sauce reduction mode initiation signal may be received from the user interface, e.g., user interface panel 154 and/or knobs 156. The sauce reduction mode initiation signal may represent or correspond to a user request for the sauce reduction mode based on a user pressing a sauce reduction mode key or button 157 or otherwise entering the request via the user interface 62. It will be understood that the sauce reduction mode includes at least one target temperature during one or more stages of the sauce reduction mode, e.g., the target temperature may be a predetermined target temperature that is stored in a memory of a controller of the cooktop appliance and/or in a memory of a remote computing device that is in communication, such as over the internet or in a distributed computing environment (e.g., cloud), with the controller of the cooktop appliance. In some exemplary embodiments, the sauce reduction mode initiation signal may include or be accompanied by a sauce attribute selection and the target temperature may be retrieved or selected such as by looking up the selected sauce attribute in a lookup table and selecting the target temperature associated with the selected sauce attribute in the lookup table. The sauce reduction mode may utilize a closed-loop control system in at least one stage of the sauce reduction mode, where the closed-loop control system may operate or adjust the cooktop appliance, e.g., power levels of one or more heating elements of the cooking appliance, based on input from a temperature sensor.
As illustrated in
Still referring to
Method 500 may also include a step 540 of determining that the reduction stage has ended. For example, the method may automatically determine that the reduction stage has ended without any further user input indicating the end of the reduction stage. The end of the reduction stage may be determined, e.g., detected, using one or more of temperature, time, call for heating, slope of the call for heating, and/or slope of the temperature. For example, the end of the reduction stage may be determined based on temperature when a temperature measured by the temperature sensor at the utensil heated by the heating element reaches a threshold, which may be less than a temperature setpoint for the reduction stage. As another example, the end of the reduction stage may be determined based on call for heating when a called-for power level that is an output of the closed loop control algorithm reaches a certain level, e.g., a certain percentage of the total power or maximum power capacity of the heating element.
In some exemplary embodiments, method 500 may also include measuring the temperature at the utensil during the preheat stage and during the reduction stage. In such embodiments, determining that the reduction stage has ended may include determining that the reduction stage has ended when the measured temperature at the utensil reaches a threshold temperature. For example, the target temperature may be set to between about 230° F. and about 360° F., such as between about 260° F. and about 340° F., such as about 300° F. or about 310° F., and the threshold temperature may be between about 200° F. and about 300° F., such as between about 225° F. and about 275° F., such as about 250° F. It should be understood that although the ranges of possible values for the target temperature and the temperature threshold overlap, the temperature threshold will be equal to or less than the target temperature.
Moreover, in some embodiments, the sauce reduction mode may include multiple temperature thresholds, e.g., the threshold temperature on which the determination of the end of the reduction stage is based may be a second threshold temperature. In such embodiments, the method may further include ending the preheat stage and beginning the reduction stage when the measured temperature at the utensil reaches a first threshold temperature less than the second threshold temperature. For example, when the second threshold temperature (at which the reduction stage is ended) is about 250° F., the first threshold temperature may be about 200° F.
As mentioned, in some embodiments, the first power level during the preheat stage, e.g., at step 520, may be a fixed power level during the preheat stage. In additional embodiments, the first power level during the preheat stage, e.g., at step 520, may be determined by a closed-loop control algorithm based on a temperature setpoint and on the measured temperature at the utensil. For example, the temperature setpoint may be greater than the threshold temperature, e.g., in order to reach the threshold temperature more quickly (e.g., as compared to when the temperature setpoint is equal to the threshold temperature) and thereby provide an expedited preheat stage in order to promote an overall shorter time duration of the sauce reduction mode. In embodiments where determining that the reduction stage has ended includes determining that the reduction stage has ended when the measured temperature at the utensil reaches the threshold temperature, as described above, the first power level may be a fixed level or may be determined by the closed-loop control algorithm.
As mentioned above, in some embodiments, the sauce reduction mode initiation signal may include or be accompanied by a sauce attribute selection, such as one or more of a sauce type identification, a sauce volume or sauce quantity selection, and/or a desired sauce thickness, among other possible example sauce attributes. In such embodiments, the method may, for example, also include determining a reduction time based on the selected sauce attribute, and determining that the reduction stage has ended may be based on the determined reduction time.
In some embodiments, the preheat stage may be based on or responsive to a boiling point of a sauce in the utensil. In such embodiments, the method may include transitioning from the preheat stage to the reduction stage when the sauce begins to boil, and the second power level may be based at least in part on a decrease in mass of the sauce in the utensil. For example, the sauce beginning to boil may correspond to water mass escaping from the sauce in the form of steam, whereby the decrease in mass of the sauce thus reduces the amount of thermal energy required to raise or maintain the temperature of the sauce as the sauce is reduced and the sauce continues to lose water mass.
In some embodiments, the sauce reduction mode may include a combined preheat and reduction stage. For example, the preheat stage and the reduction stage of the method 500 may be performed continuously and successively after receiving the sauce reduction mode initiation signal. The sauce reduction mode may also be completely automated, such as permitting the entire mode to be performed in response to a single or otherwise limited user input, such as without any additional user inputs after the sauce reduction mode has been initiated, e.g., the preheat stage and the reduction stage may be performed after receiving the sauce reduction mode initiation signal without any additional user input during the preheat stage, during the reduction stage, or between the preheat stage and the reduction stage.
When the reduction stage has ended, exemplary methods according to the present disclosure may include decreasing the power level of the heating element. It is understood that the heating element inherently has a power level of zero or greater at all times, such that the term “the power level of the heating element” has inherent antecedent basis in the recitation of the heating element. In some embodiments, decreasing the power level of the heating element after the reduction stage may include setting the heating element to a very low (but greater than zero) power level or setting the power level to zero, e.g., deactivating the heating element. For example, after step 540, method 500 may include deactivating the heating element because the reduction stage has ended, e.g., as indicated at 550 in
Still referring to
In some embodiments, the method may further include waiting a resting period after decreasing the power level of the heating element, and, in such embodiments, the user notification may be provided after the resting period. The resting period may be a fixed and predetermined amount of time, such as based on an identified sauce attribute, or may be a common time value for all sauces. For example, the resting period may be between about two minutes and about fifteen minutes, such as between about five minutes and about ten minutes, such as about three minutes, or about five minutes, or about seven minutes. The resting period may instead be based on temperature. For example, the end of the resting period may be determined when the temperature measured by the temperature sensor(s) reaches a predetermined threshold such as a third temperature threshold lower than the second temperature threshold, e.g., a serving temperature.
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.