The present subject matter relates generally to methods for selecting the power cycle in appliances.
Closed loop cooking (CLC or Precision Cooking) on cooking appliances is a feedback system to measure a variable and control the appliance based on the error between the variable setpoint and the variable's current value. During CLC, the power to the cooking element is cycled on and off during operation depending on the amount of heating power needed by the cooking cycle. Typically, the power is controlled with a predefined frequency or period. During this cycling period, the ratio of the on time versus the total time is changed to produce different power levels. This ratio is also called the duty cycle. Whenever the cooking algorithm calls for a change in power level, the duty cycle is changed to adjust the average power being applied to the cooking element.
Conventionally, the power is controlled with a fixed cycle period and the duty cycle is changed. However, since the cycle time is conventionally fixed, the appliance system cannot adjust appropriately and rapidly in all situations. A method to select an appropriate cycle period would be advantageous.
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 method of closed loop cooking on an appliance includes receiving, at a controller, input parameters for a cooking operation. Determining, by the controller, a power cycle period in response to the input parameters. Operating, by the controller, the cooking operation with the power cycle period.
In another example embodiment, a method of closed loop cooking on an appliance includes receiving, at a controller, input parameters for a cooking operation. Determining, by the controller, operation parameters in response to the input parameters. Selecting, by the controller, a cycle period time in response to the operation parameters. Operating, by the controller, the cooking operation with the power cycle period.
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.
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.
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.
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 (i.e., “A or B” is intended to mean “A or B or both”). Approximating language, as used herein throughout the specification and claims, is 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 “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. For example, the approximating language may refer to being within a ten percent (10%) margin. Similarly, a state of operation modified by the term “semi-cycle” is not meant to be limited to exactly half of a cycle, as the “semi-cycle” may be more or less than half of the cycle.
Referring now to the figures,
Cooktop appliance 100 includes a ceramic plate 110 for supporting cooking utensils, such as pots, skillets, woks, pans, or any other suitable cooking utensil on a cooking or top surface 114 of ceramic plate 110. Ceramic plate 110 may be any suitable ceramic or glass plate. Heating assemblies 122 are mounted below ceramic plate 110 such that heating assemblies 122 are positioned below ceramic plate 110, as would be understood in the art. Ceramic plate 110 may be continuous over heating assemblies 122.
While shown with four heating assemblies 122 in the example embodiment of
Cooktop appliance 100 may be controlled by a control board or controller 140. Controller 140 may be in communication (via for example a suitable wired or wireless connection) to components of cooktop appliance 100, such as heating assembly 122. By way of example, controller 140 may include a memory and one or more processing devices such as microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of cooktop appliance 100. The memory may be a separate component from the processor or may be included onboard within the processor. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH.
A user interface 130 provides visual information to a user and allows a user to select various options for the operation of cooktop appliance 100. For example, displayed options can include a desired heating assembly 122, a desired cooking temperature, and/or other options. User interface 130 can be any type of input device and can have any configuration. In
In the example embodiment shown in
Heating assembly 122 of cooktop appliance 100 may be cycled between an on semi-cycle and an off semi-cycle. The power to heating assembly 122 may be cycled during a cooking operation depending on the amount of heating power, otherwise known as the power level, that is needed by the cooking operation. Generally, the power may be controlled with a predefined cycle frequency/period. During this cycle period, the ratio of the on semi-cycle time versus the total period time may be changed to produce different power levels, and the ratio may be called a duty cycle. As an example, the duty cycle may be calculated with the following
wherein the “ON Time” is the amount of time the heating element, such as heating assembly 122, is active, and the “Period” is the total length of the power cycle, i.e., the sum of the on and off semi-cycle times. Whenever a user or a cooking algorithm calls for a power level change, the duty cycle of heating assembly 122 may be changed. A power cycle period of twenty seconds (20 s) is adequate for most closed-loop cooking (CLC). However, a power cycle period of twenty seconds (20 s) may be too long for some foods and cooking techniques, as some foods and cooking techniques require rapid changes in power delivery. For example, a short power cycle period may be chosen for foods with sensitive thermal properties, such as melting chocolate, or a propensity to burn, such as sugar. During CLC, a user may set a desired cooking temperature, and an appliance algorithm adjusts the power level during the cooking operation based upon sensor feedback, and may further adjust the power cycle period in order to achieve the desired results. Thus, e.g., in the above example equation, the power cycle period may correspond to the “Period” such that increasing or decreasing the “Period” may be adjusted to change the heat output characteristics of the heating element, e.g., while maintaining a constant % Duty Cycle associated with the selected operating point for the heating element.
Method 300 may also include notifying the user of a cooking instruction during the cooking operation. For example, the cooking instruction may include recommending cooking actions, such as turning, flipping, and/or stirring. The cooking instructions may also include displaying timing tips and explaining the determination of when the cooking operation is complete. The cooking operation may be ended by the user input or the expiration of a timer. Alternatively or additionally, the user may input a cooking utensil material, where in-addition to the input parameters, controller 140 may determine the power cycle period in response to the cooking utensil material.
At 440, controller 140 may perform the cooking operation with the selected power cycle period. For example, controller 140 may receive the input parameters from a user selecting a food type of chocolate, with a food quantity of two (2) ounces. Controller 140 may determine the operation parameters, such as a target temperature of fifty-two degrees Celsius (52° C.), in response to the received input parameters. Then, controller 140 may select the power cycle period of ten (10) seconds based on the operation parameters. Controller 140 may then perform the cooking operation at the power cycle period of ten (10) seconds. In an alternative embodiment, some operation parameters, such as target temperature, may be inputted by the user as an input parameter at 410. At 420, controller 140 may determine operation parameters in response to the input target temperature. The operation parameters may include temperature-based cooking instructions, and estimated food sensitivity. At 430, controller 140 may select the power cycle period in response to the operation parameters. At 440, controller 140 may perform the cooking operation with the selected power cycle period.
As referred to above,
Further, in either of method 300 or method 400, the user may choose whether to enter the input parameters of food type, food quantity, or target temperature. The appliance may provide information to the user either on user interface 130 or an external device. The external device, such as a smartphone, may be connected to controller 140 and capable of sending control signals via wireless communication, such as via a cloud network. For example, cooking instructions and cycle status may be shown on user interface 130 or the external device. The input parameters may include more user selections that may provide more granular tuning of the power cycle period and other parameters. For example, the user may select a desired doneness for a hamburger, or desired cycle cooking time, or the cooking utensil material. The power cycle period may be determined or selected based upon one or any combination of these parameters. Additional operation parameters may be included such as cooking time, controller 140 gains, and maximum allowed temperature error while cooking. Additionally, instead of table 500, controller 140 may use an equation or transfer function to calculate the power cycle period, or other parameters.
As may be seen from the above, the present disclosure may provide a method or methods of operating an appliance in order to select the power cycle period for a cooking operation based upon input parameters. Controller 140 may control the cooking operation during closed loop cooking more appropriately than conventional methods. Controller 140 may receive the input parameters, determine, and select the power cycle period accordingly, and perform the cooking operation.
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.