Cooking system temperature management

Abstract

According to one or more implementations, a method for operating heating elements disposed in a heating chamber of a cooking system is disclosed. The method includes receiving a zero-crossing indication defined based on alternating current and by a zero-crossing circuit. The method includes energizing a first one of the heating elements with the alternating current based on the zero-crossing indication and in accordance with a modulation schedule.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Application 63 / 006,300, filed April 7, 2020, entitled “Temperature Management of Cooking Systems,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The embodiments of this disclosure generally relate to cooking systems, and more specifically, to temperature management of cooking systems. Background Technology

[0004] For example, existing countertop cooking systems (such as ovens) can be used to conveniently heat or cook food, replacing larger wall-mounted ovens or stovetops. Countertop cooking systems typically cover a significant amount of counter space. In kitchens with limited counter space, the space occupied by a countertop cooking system when not in use is inconvenient for the user. Therefore, users may store the countertop cooking system elsewhere, reducing its accessibility and ease of use. Summary of the Invention

[0005] According to one or more implementations, a cooking system is disclosed. The cooking system includes an AC bus configured to conduct alternating current (AC) of a defined period. The cooking system includes a heating chamber. The cooking system includes a heating element, which includes a first heating element disposed within the heating chamber and associated with the AC bus to conduct AC current through the first heating element. The cooking system includes a first switch operable, when actuated, to control the energization of the first heating element. The cooking system includes a zero-crossing circuit cooperating with the AC bus, the zero-crossing circuit being configured to output a zero-crossing indication based on a period. The cooking system includes a controller having a digital memory and instructions stored in the digital memory in a controller-readable form, the instructions including a modulation schedule. The instructions, when executed by the controller, are operable to receive the zero-crossing indication. The instructions, when executed, are further operable to operate the first switch based on the zero-crossing indication and according to the modulation schedule to energize the first heating element with AC current.

[0006] According to one or more implementations, a method for operating a heating element disposed in a heating chamber of a cooking system is disclosed. The method includes receiving a zero-crossing indication based on alternating current and defined by a zero-crossing circuit. The method further includes energizing a first heating element among the heating elements with alternating current based on the zero-crossing indication and according to a modulation schedule. Attached Figure Description

[0007] Several aspects of this disclosure are illustrated in conjunction with the accompanying drawings, which are included and form part of this specification, and serve, together with the description, to explain the principles of this disclosure. In the drawings:

[0008] FIG. 1A depicts a front perspective view of a cooking system, in accordance with one or more implementations of the present disclosure;

[0009] FIG. 1B depicts a side cross-sectional view of a cooking system, in accordance with one or more implementations of the present disclosure;

[0010] FIG. 2 depicts a schematic view of a cooking system, in accordance with one or more implementations of the present disclosure;

[0011] FIG. 3A depicts a modulation schedule for a cooking system with 1500W consumption, in accordance with one or more implementations of the present disclosure;

[0012] FIG. 3B depicts a modulation schedule for a cooking system with 1000W consumption, in accordance with one or more implementations of the present disclosure;

[0013] FIG. 3C depicts a modulation schedule for a cooking system with 750W consumption, in accordance with one or more implementations of the present disclosure;

[0014] FIG. 3D depicts a modulation schedule for a cooking system with 600W consumption, in accordance with one or more implementations of the present disclosure;

[0015] FIG. 3E depicts a modulation schedule for a cooking system with 500W consumption, in accordance with one or more implementations of the present disclosure;

[0016] FIG. 3F depicts a modulation schedule for a cooking system with 250W consumption, in accordance with one or more implementations of the present disclosure;

[0017] FIG. 4 depicts a method for operating a cooking system, in accordance with one or more implementations.

[0018] One or more, but not all, implementations of the present disclosure are described in detail below. DETAILED DESCRIPTION

[0019] Reference FIGS. 1A-1BA cooking system 100 is shown. The cooking system 100 includes a heating chamber 102 for heating food and an electrical plug 104 for providing electrical energy to the cooking system 100. The cooking system 100 includes feet for support and a door for closing the heating chamber 102. It should be understood that the heating chamber 102 can be any type of heating cavity or heating surface. The heating chamber 102 can be a cooktop or a range top. The cooking system 100 can be sized to fit on a countertop. The cooking system 100 is operable to enable a user to rotate from a horizontal position (as shown) to a vertical position for storage. In fact, the cooking system 100 can be shallow to allow nesting under a kitchen cabinet. As an example, the width 106 and the depth 108 can be similar or substantially similar, and the height 110 can be less than each of the width 106 and the depth 108. The height 110 can be less than half of each of the width 106 and the depth 108. The height 110 can be less than one-third of each of the width 106 and the depth 108.

[0020] The heating chamber 102 includes at least one heating element. As an example, the heating chamber 102 includes heating elements 112, 114, 116, 118. The heating elements 112, 114, 116, 118 can be any type, including: metallic, ceramic, semiconductive, thick film, polymeric, or any combination thereof. The heating element 112 can be a first heating element or any other (second, third, fourth) heating element, as it should be understood that the first, second, third, etc. designations are for clarity only and the references in the specification or claims should not be limited to any one of the heating elements 112, 114, 116, 118. The first heating element 112 heats a first heating zone 132 relative to a cooking surface 120. The cooking surface 120 can be any type of cooking surface 120 or combination thereof. As an example, the cooking surface 120 can be a fry basket, a griddle, a grate, a grill and / or a pan, bowl or similar item placed on a grill or other surface, or any other type of container for food. It should be understood that multiple cooking surfaces 120 can be inserted into the heating chamber 102 at the same time. As shown, the first heating element 112 traverses the heating chamber 102 across the width 106. It should be understood that the heating elements 112, 114, 116, 118 can be oriented in any manner about the heating chamber 102.

[0021] A second heating element 114 is disposed in the heating chamber 102. The second heating element 114 can traverse the width 106 of the heating chamber 102. The second heating element 114 is associated with a second heating zone 134. It should be understood that the heating zones 132, 134, 136 can be defined solely in terms of the heating elements 112, 114, 116, and the physical designations are unnecessary.

[0022] A third heating element 116 is disposed in the heating chamber 102. The third heating element 116 can span the width 106 of the heating chamber 102. The third heating element 116 is associated with a third heating zone 136. As shown, each of the heating elements 112, 114, 116 can be spaced across the depth 108 of the heating chamber 102. The heating elements 112, 114, 116 can be disposed on a top plate of the heating chamber 102 in the heating chamber 102.

[0023] A fourth heating element 118 or combination of heating elements can be disposed in the heating chamber 102. The fourth heating element 118 can be disposed on a base plate or floor of the heating chamber 102 (close to the bottom).

[0024] The heating elements 112, 114, 116, 118 provide thermal energy to the heating zones 132, 134, 136 by conduction to air in the respective heating zones 132, 134, 136 in contact with the heating elements 112, 114, 116, 118, by convection of air in the heating zones 132, 134, 136 in contact with the heating elements 112, 114, 116, 118 by motion of the air, and by radiation from the heating elements 112, 114, 116, 118 to any items in the heating zones 132, 134, 136.

[0025] The heating elements 112, 114, 116 can be disposed anywhere in the heating chamber 102. The heating elements 112, 114, 116 can be separated by baffles 122, 124. The first baffle 122 can deflect heat radiated from the first heating element 112 away from the second heating zone 134, thereby directing the radiated heat toward the first heating zone 132. The second baffle 124 can deflect heat radiated from the second heating element 114 away from the third heating zone 136, thereby directing the heat toward the second heating zone 134. The first baffle 122 can deflect heat radiated from the second heating element 114 away from the first heating zone 132, thereby directing the radiated heat toward the second heating zone 134. And, the second baffle 124 can deflect heat radiated from the third heating element 116 away from the second heating zone 134, thereby directing the radiated heat toward the third heating zone 136.

[0026] It should be understood that any of the heating elements 112, 114, 116, 118 can include any number of elements or heat generating partitions. It should be understood that the heating elements 112, 114, 116, 118 can be disposed on any wall of the heating chamber 102. As an example, the first heating element 112 can be disposed on a top plate of the heating chamber 102, the second heating element 114 can be disposed on a back wall of the heating chamber 102, the third heating element 116 can be disposed on a side wall of the heating chamber 102, and the fourth heating element 118 can be disposed on a floor of the heating chamber. Any disposition of the heating elements 112, 114, 116, 118 is contemplated in the present disclosure.

[0027] Referring to FIG. 2 , a schematic diagram of the cooking system 100 is shown. The schematic diagram depicts a control system of the cooking system 100. The plug 104 can be plugged into an electrical outlet to provide power to the cooking system 100. It should be understood that the plug 104 can also represent a hardwire connection to an electrical bus. The plug 104 is connected to an alternating current bus 146 to provide alternating current 147 (as shown in FIGS. 3A-3F ). The alternating current bus 146 can define an alternating current bus power rating. The alternating current bus power rating can be based on government standards or other regulations related to the current capacity of the alternating current bus 146. As an example, the alternating current bus power rating can be 1800W, corresponding to 15A at 120Vac. It should be understood that different current bus power ratings are contemplated by the present disclosure and the number and modulation schedule 200 of the heating elements 112, 114, 116, 118 can be modified to utilize any potential alternating current bus power rating including 2400W.

[0028] The first heating element 112 can have a first power consumption of 500W when operating at full power without modulation. The second heating element 114 can have a second power consumption of 500W when operating at full power without modulation. The third heating element 116 can have a third power consumption of 500W when operating at full power without modulation. The fourth heating element 118 or plurality of heating elements can have a fourth power consumption of 750W when operating at full power without modulation. Thus, the cumulative power consumption rating of all of the heating elements 112, 114, 116, 118 (e.g., 2250W) is greater than the alternating current bus power rating of 1800W. Thus, full power operation of the heating elements 112, 114, 116, 118 without modulation can exceed the alternating current bus power rating during operation.

[0029] The controller 140 is shown as having a digital memory 142 and a processor 144. The controller 140 can include any combination of processors, field programmable gate arrays (FPGAs), or application specific integrated circuits (ASICs). The controller 140 can include memory (volatile and non-volatile) operable to store machine instructions from the processor and other processing mechanisms to receive, compute, and control the apparatus as needed. The machine instructions can be stored (e.g., stored instructions, stored machine instructions, stored steps) in any language or representation (including, but not limited to, machine code, assembly instructions, C, C++, C#, PASCAL, COBAL, PYTHON, JAVA, and RUBY). It should be understood that for any communication from the controller 140, any type of wired or wireless configuration can be understood. The controller 140 can broadly address the problem of heating food with the cooking system 100. There are many solutions to the problem of heating food today. As an example, microwave radiation can be used instead of infrared radiation to heat food. Thus, the present disclosure does not attempt to preclude all solutions to the problem of heating food. One or more non-contemporary solutions to the problem of heating food are described herein.

[0030] One such application in accordance with one or more implementations of the present disclosure includes a controller 140 configured to receive a zero-crossing indication 149 from a zero-crossing circuit 148. The controller 140 can receive the zero-crossing indication 149 as a discrete input or another type of input (e.g., analog, digital). The zero-crossing circuit 148 can be any implementation and disposed between the AC power bus 146 and the controller 140. For brevity, resistors and other basic elements (e.g., resistors, capacitors, inductors) are not shown. The zero-crossing circuit 148 can be or can include a LITE-ON LTV817C chip with a diode transistor optocoupler. The zero-crossing circuit 148 can include galvanic isolation to separate the AC power bus 146 from the controller 140.

[0031] The AC power bus 146 can power the light 150, the convection fan motor 156, and the heating elements 112, 114, 116, 118. The switches 152, 158, 162, 172, 182, 192 can be used to individually operate the light 150, the motor 156, and the heating elements 112, 114, 116, 118, respectively. The switches 152, 158, 162, 172, 182, 192 can be triacs, SCRs, MOSFETs, electromechanical relays, IGFTs, or any other implementation that enables current or voltage control of the switches 152, 158, 162, 172, 182, 192. The first switch 162 can be connected with the first heating element 112.

[0032] A light switch 152 can be connected with the light 150. The light switch 152 can include a light gate 154 operable to cause the alternating current 147 to flow from the alternating current bus 146 through the light 150. The light gate 154 can be controlled by the controller 140 through an output of the controller 140 that is current or voltage controlled.

[0033] When turning power on and off to the heating elements 112, 114, 116, 118, it can cause a power surge to the light 150, causing the potential for flicker. It has been found that switching at a rate of 15 times or more per second eliminates flicker visible to humans. Accordingly, the modulation schedule 200 can be increased by multiples of 15 to reduce flicker visible to humans.

[0034] A motor switch 158 can be connected with the motor 156. The motor switch 158 can include a motor gate 159 operable to cause the alternating current 147 to flow from the alternating current bus 146 through the motor 156. The motor gate 159 can be controlled by the controller 140 through an output of the controller 140 that is current or voltage controlled.

[0035] A first switch 162 can be connected with the first heating element 112. The first switch 162 can include a first gate 164 operable to cause the alternating current 147 to flow from the alternating current bus 146 through the first heating element 112. The first gate 164 can be controlled by the controller 140 through an output of the controller 140 that is current or voltage controlled.

[0036] A second switch 172 can be connected with the second heating element 114. The second switch 172 can include a second gate 174 operable to cause the alternating current 147 to flow from the alternating current bus 146 through the second heating element 114. The second gate 174 can be controlled by the controller 140 through an output of the controller 140 that is current or voltage controlled.

[0037] A third switch 182 can be connected with the third heating element 116. The third switch 182 can include a third gate 184 operable to cause the alternating current 147 to flow from the alternating current bus 146 through the third heating element 116. The third gate 184 can be controlled by the controller 140 through an output of the controller 140 that is current or voltage controlled.

[0038] A fourth switch 192 can be connected with the fourth heating element 118. The fourth switch 192 can include a fourth gate 194 operable to cause the alternating current 147 to flow from the alternating current bus 146 through the fourth heating element 118. The fourth gate 194 can be controlled by the controller 140 through an output of the controller 140 that is current or voltage controlled. The fourth switch 192 can be an electromechanical relay.

[0039] The controller 140 can be configured by circuitry or otherwise include instructions for providing additional operations of the cooking system 100. As an example, the controller 140 can be integrated with a user interface operable to enable a user to select a cooking system wattage, set a cooking time, display a current time, a chime, follow a recipe, and perform other necessary human-machine interactions. The user interface can include a display. The user interface can include knobs, buttons, or other controls to allow user interaction. The user interface can include a display.

[0040] Referring to FIGS. 3A-3F , a modulation schedule 200 is shown. The modulation schedule 200 can be set on the digital memory 142 or within the controller 140 to operate the switches 152, 158, 162, 172, 182, 192 according to the modulation schedule 200. As an example, the modulation schedule 200 can be defined as a case statement on the digital memory 142 with a respective modulation scheme depicted in each of FIGS. 3A-3F to operate the cooking system 100 according to a user’s selection. That is, the cooking system 100 is operable to enable a user to define the power consumption of the cooking system 100 through the modulation schedule 200. It should be understood that the repeated indication of reference numerals (e.g., 202) is not shown in FIGS. 3A-3F for the sake of clarity.

[0041] As an example, in FIG. 3A , the modulation schedule 200 defines full power consumption of the first heating element 112 (controlled by the first thyristor 162), the second heating element 114 (controlled by the second thyristor 172), and the third heating element 116 (controlled by the third thyristor 182) at a 100% duty cycle. The thyristors can be any other implementation of a switch. Such operation can occur during a user-selected toasting operation. Thus, the power consumption of the cooking system 100 is 1500W and less than the AC bus power rating (1800W). The AC power 147 defines a zero-crossing 202 and a cycle 204. The zero-crossing 202 can be defined where the AC power 147 is zero or the voltage of the AC power 147 is zero. As shown, the cycle 204 can be a full current spectrum of the AC power 147 of 360 degrees. The cycle 204 can also be defined as a partial spectrum of the AC power 147 (e.g., 180 degrees, 90 degrees, 45 degrees). Thus, the fourth heating element 118 can be turned off to ensure that the AC bus power rating is not exceeded. It should be understood that the controller 140 can be configured to stop the AC power 147 before completion of a full cycle (e.g., 135). The cycle can be defined to start and end at any number of degrees. The cycle can be defined to start and end at zero degrees, 90 degrees, 180 degrees, or 360 degrees. The cycle can be any number of degrees including multiples of the aforementioned degrees (e.g., 720).

[0042] As an example, the cycle can begin at 30 degrees and end at 360 degrees or another number of degrees. As another example, the cycle can begin at zero degrees and end at 180 degrees. It should be appreciated that the present disclosure includes all heating elements 112, 114, 116, 118 for a portion of the statement for a particular modulation scheme to be energized individually such that all heating elements 112, 114, 116, 118 are energized individually without requiring all heating elements 112, 114, 116, 118 to be energized simultaneously, thereby allowing operation of all heating elements 112, 114, 116, 118 having a cumulative power consumption rating greater than the AC bus power rating of the AC bus 146. Accordingly, heat is spread around the heating chamber 102.

[0043] It should be appreciated that one or more of the heating elements 112, 114, 116, 118, or any combination thereof, can have a cumulative power consumption rating (e.g., 2250W) that is greater than the AC bus power rating (e.g., 1800W) of the AC bus 146. The modulation schedule 200 can operate one or more of the heating elements 112, 114, 116, 118, or any combination thereof, to have a cumulative power consumption (e.g., 1750W) that is less than the AC bus power rating. It should be appreciated that this can be important when substantially uniform heating across the heating zones 132, 134, 136 is desired. That is, the modulation schedule 200 provides substantially uniform heating across the heating zones 132, 134, 136, or any combination thereof, while energizing the heating elements 112, 114, 116, 118, or any combination thereof, having a cumulative power consumption greater than the AC bus power rating.

[0044] As another example, in FIG. 3B the modulation schedule 200 defines 1000W or fourth heating element 118 operation of the cooking system 100. As shown, the modulation schedule 200 has a cycle 204. The number of cycles 204 (e.g., 3 representing 360 cycles, 6 representing 180 cycles, 12 representing 90 cycles) defines a first time period 206. The on state 212 of the respective switches 152, 158, 162, 172, 182, 192 representing the associated state of the gates 154, 159, 164, 174, 184, 194 can define a duty cycle according to the first time period 206. As shown, the on state 212 is less than or equal to two-thirds (2:3, 66%), indicating that each of the switches 162, 172, 182 are on for two cycles and off for one cycle.

[0045] As shown, the first time period 206 is offset from the second time period 208 having the same number of cycles 204, such that the first heating element 112 is energized one cycle 204 before the second heating element 114 is energized and de-energized before the second heating element 114 is de-energized. A third time period can be defined for the third heating element 116 that is offset from the first time period 206 and the second time period 208. As shown, although the first heating element 112, the second heating element 114, and the third heating element 116 are energized to provide 1000 W of heat, only two of the heating elements 112, 114, 116 are energized at any time. It will be appreciated that the fourth heating element 118 can be energized during this modulation scheme such that the total consumption of the heating elements 112, 114, 116, 118 is 1750 W and less than the 1800 W AC bus power rating.

[0046] Referring to FIG. 3C , the modulation schedule 200 defines a 750 W operation of the cooking system 100 or a 1500 W operation of the fourth heating element 118. As shown, the modulation schedule 200 has cycles 204. The number of cycles 204 (e.g., two representing 360 cycles) defines a first time period 206. A duty cycle can be defined from the first time period 206. As shown, the duty cycle is one-half (1 :2, 50%) indicating that each of the switches 162, 172, 182 is on for one cycle and off for one cycle. As shown, the first time period 206 is offset from the second time period 208 having the same number of cycles 204, such that the first heating element 112 is energized one cycle 204 before the second heating element 114 is energized and de-energized before the second heating element 114 is de-energized. The third heating element 116 can be energized from the first time period 206 and the one-half duty cycle. It will be appreciated that the fourth heating element 118 can be energized during this modulation scheme such that the total consumption of the heating elements 112, 114, 116, 118 is 1500 W and less than the 1800 W AC bus power rating.

[0047] Referring to FIG. 3Dmodulation schedule 200 defines a 600 W operation of the cooking system 100 or a 1350 W operation of the fourth heating element 118. As shown, the modulation schedule 200 has a number of periods 204. The number of periods 204 (e.g., five representing 360 periods) defines a first time period 206. The on state 212 of the respective switches 152, 158, 162, 172, 182, 192 representing the associated state of the gates 154, 159, 164, 174, 184, 194 can define a first duty cycle according to the first time period 206. As shown, the first duty cycle is one in three (1 :3, 33%) indicating that each of the switches 162, 182 is on for two periods and off for three periods. A second time period 208 can also be defined as five periods 204, where a second on state 214 of the respective switches 152, 158, 162, 172, 182, 192 representing the associated state of the gates 154, 159, 164, 174, 184, 194 can define a second duty cycle of two in five (2:5, 40%).

[0048] As shown, the first time period 206 is offset from the second time period 208 having the same number (5) of periods 204 such that the first heating element 112 is energized for one period 204 before the second heating element 114 is energized and de-energized after the second heating element 114 is de-energized. The third heating element 116 can be energized similarly to the first heating element 112. It should also be understood that the modulation scheme shown, where the modulation schedule 200 is defined by a fifteen period schedule instead of a five period schedule. It should be understood that the fourth heating element 118 can be energized during this modulation scheme such that the total consumption of the heating elements 112, 114, 116, 118 is 1350 W and less than the 1800 W AC bus power rating. FIG. 3D

[0049] Referring to FIG. 3E ​modulation schedule 200 defines a 500W operation of the cooking system 100 or a 1250W operation of the fourth heating element 118. As shown, the modulation schedule has a period 204. The number of periods 204 (e.g., three representing 360 periods) defines a first time segment 206. A duty cycle can be defined from the first time segment 206. As shown, the on state 212 of the respective switches 152, 158, 162, 172, 182, 192 representing the associated state of the gates 154, 159, 164, 174, 184, 194 can define a first duty cycle of one in three (1:3, 66%), indicating that each of the switches 162, 172, 182 are on for one period and off for two periods. As shown, the first time segment 206 is offset from a second time segment 208 having the same number of periods 204, such that the first heating element 112 is energized for one period 204 before the second heating element 114 is energized and de-energized before the second heating element 114 is de-energized. The third heating element 116 can be energized from the first time segment 206 and the one in three duty cycle. It should be understood that the fourth heating element 118 can be energized during this modulation scheme such that the total consumption of the heating elements 112, 114, 116, 118 is 1250W and less than the 1800W AC bus power rating.

[0050] Referring to FIG. 3F modulation schedule 200 defines a 250W operation of the cooking system 100 or a 1000W operation of the fourth heating element 118. As shown, the modulation schedule has a period 204. The number of periods 204 (e.g., six representing 360 periods) defines a first time segment 206. A duty cycle can be defined from the first time segment 206. As shown, the on state 212 of the respective switches 152, 158, 162, 172, 182, 192 representing the associated state of the gates 154, 159, 164, 174, 184, 194 can define a first duty cycle of one in six (1:6, 16%), indicating that each of the switches 162, 172, 182 are on for one period and off for five periods. As shown, the first time segment 206 is offset from a second time segment 208 having the same number of periods 204, such that the first heating element 112 is energized for one period 204 before the second heating element 114 is energized and de-energized before the second heating element 114 is de-energized. The third heating element 116 can be energized from the first time segment 206 and the one in three duty cycle. It should be understood that the fourth heating element 118 can be energized during this modulation scheme such that the total consumption of the heating elements 112, 114, 116, 118 is 1250W and less than the 1800W AC bus power rating.

[0051] It should be appreciated that a duty cycle can refer to a fraction of the respective time periods 206, 208, 210 in which the switches 152, 158, 162, 172, 182, 192 are on and off. The duty cycle can be one or more of the periods in the time periods 206, 208, 210. As an example, the time periods 206, 208, 210 can be three periods 204. If the duty cycle is one third, then the respective switch 152, 158, 162, 172, 182, 192 can be on in the first, second, or third (last) period. If the duty cycle is two thirds, then the respective switch 152, 158, 162, 172, 182, 192 can be on in the first and second, first and third, or second and third periods.

[0052] With reference to FIG. 4The method 300 is depicted. It should be understood that any of the steps can be omitted, rearranged, or repeated. The steps can be performed concurrently or serially. In step 302, the AC power 147 is received. The AC power 147 can be received by the zero crossing circuit 148 in order to output the zero crossing indication 149 in step 304. The zero crossing indication 149 can be a pulsed output indicating where the AC power 147 is zero. In step 306, the controller 140 receives the zero crossing indication 149. Registers on the controller 140 can be set and cleared based on the zero crossing indication 149. In step 308, the first heating element 112 is energized. The first heating element 112 can be energized by the controller 140. As an example, the controller 140 can control the switch 162 to allow or prevent the AC power 147 from flowing through the first heating element 112. The first heating element 112 can be energized based on the zero crossing indication 149. The first heating element 112 can be energized according to the modulation schedule 200. The modulation schedule 200 can be stored as instructions on the controller 140. As an example, the modulation schedule 200 can be defined as a set of cases or case statements. A case can be selected based on user input through a user interface. As an example, the user interface can allow a user to select a toast. The toast can identify a case statement or a modulation scheme within the stored modulation schedule 200. The case statement can include a series of steps for energizing the first heating element 112 with the first switch 162. As a non-limiting practical example, the steps can include: detecting a cycle based on the zero crossing indication 149 (e.g., every other zero crossing indication 149 is a full cycle); initializing a cycle count (e.g., count = 0); receiving a duty cycle or retrieving a defined duty cycle; receiving a time period 206, 208, 210 or retrieving a predefined time period 206, 208, 210 associated with the case statement; based on the duty cycle and the time period 206, 208, 210, setting a tag or an identifier associated with a digital output and the switch 162 to true according to the case statement; based on the duty cycle and the time period 206, 208, 210, setting the tag or the identifier associated with the digital output and the switch 162 to false according to the case statement. Thus, the controller 140 can energize the first heating element 112 based on the duty cycle and the time period 206, 208, 210 associated with the case statement or the modulation scheme.

[0053] In step 310, the second heating element 114 can be energized as described above, similar to the first heating element 112. In step 312, the third heating element 116 can be energized as described above, similar to the first heating element 112. In step 314, the fourth heating element 118 can be energized as described above, similar to the first heating element 112. It will be appreciated that each of the heating elements 112, 114, 116, 118 can be energized with a respective digital output, driver, switch 152, 158, 162, 172, 182, 192, and synchronized according to the zero-crossing indication 149 and the controller 140 to energize the heating elements 112, 114, 116, 118 according to the modulation schedule 200.

[0054] It will be appreciated that the wattage used by the heating elements 112, 114, 116, 118 can be defined according to a feedback loop. As an example, a user interface can be operable to enable a user to select a temperature of the heating chamber 102. The controller 140 can be configured to receive the selected temperature. The controller 140 can be configured to receive a recipe to vary the temperature over time. The controller 140 can be configured to receive a temperature in the heating chamber 102 by a temperature sensor 143 associated with an analog input. The controller 140 can then select a case statement or modulation scheme of the modulation schedule 200 based on the received temperature. As an example, the temperature can be less than the selected temperature. The controller 140 can select a case statement associated with a wattage greater than the current case to increase the temperature. As an example, if the selected temperature is 300F, and the controller 140 is operating the heating elements 112, 114, 116, 118 at 250W, and the temperature inside the heating chamber 102 is 275F, the controller 140 can select a case where the heating elements 112, 114, 116, 118 are operated at 500W. FIG. 3F FIG. 3E

[0055] It will be appreciated that the present disclosure contemplates the first, second, and third time periods to be offset from each other in any number of cycles, in any direction (before or after).

[0056] The light switch 152 and the motor switch 158 can be phase angle controlled. That is, the light 150 and the motor 156 can be energized for a portion of a cycle that begins a phase delay from the zero-crossing indication 149 and ends on a zero-crossing of the cycle 204. The phase delay can be based on the number of heating elements 112, 114, 116, 118 energized according to the modulation scheme (e.g., FIG. 3D ) As an example, FIG. 3D The modulation scheme shown can correspond to a cycle of 8.3ms and a phase delay of 1.2ms.

[0057] ​​All references cited herein, including publications, patent applications, and patents, are hereby incorporated by reference to the same extent as if each reference were individually and specifically incorporated by reference and was specifically stated to be incorporated by reference herein in its entirety.

[0058] It should be understood that any reference to first, second, third, fourth, etc. is used for clarity only and that the claims can be interchanged and limit the disclosure to that particular heating element. As an example, for clarity, the first heating element is simply a heating element with a particular name. It can also be a second heating element or any other heating element. Nothing is presented or intended to limit the disclosure based on the name for clarity.

[0059] Unless otherwise stated herein or clearly contradicted by context, the use of the terms "a" and "an" and "the" and similar referents in the context of describing the disclosure (especially in the context of the following claims) are to be construed to cover both the singular and plural forms. The terms "comprising," "having," "including," and "containing," are to be construed as open-ended terms (i.e., meaning "including, but not limited to") unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated in the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.

[0060] Exemplary embodiments of the disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Variations of those embodiments can become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the disclosure to be practiced with different specific details, including those not specifically described herein. Accordingly, the disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto, as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise apparent to one of ordinary skill in the art.

Claims

1. A cooking system, comprising: An AC bus is configured to conduct AC current with a defined period. Heating chamber; A heating element, including a first heating element disposed in the heating chamber and associated with the AC bus to conduct the AC power through the first heating element; The first switch, when actuated, can be operated to control the energization of the first heating element; A zero-crossing circuit, cooperating with the AC bus, is configured to output a zero-crossing indication based on the period; The controller has a digital memory and instructions stored in the digital memory in a controller-readable form, the instructions including a plurality of modulation schedules, each of the plurality of modulation schedules predefining different energization controls of the heating element, the instructions being operable, when executed by the controller, to receive the zero-crossing indication, wherein, when executed, the instructions are further operable, based on the zero-crossing indication and according to one of the plurality of modulation schedules, to operate the first switch to energize the first heating element with the alternating current.

2. The cooking system according to claim 1, wherein, The heating element has a cumulative power consumption rating greater than the AC bus power rating, and the cumulative power consumption of the heating element energized according to one of the plurality of modulation schedules is less than the AC bus power rating.

3. The cooking system according to claim 1, wherein, The heating element further includes a second heating element and a fourth heating element; and further includes: The second switch, when actuated, can be operated to control the power supply to the second heating element; The fourth switch, when actuated, can operate to control the energization of the fourth heating element, and The instruction, when executed by the controller, can further operate to: The second switch is operated based on the zero-crossing indication and according to one of the plurality of modulation schedules to energize the second heating element with the alternating current. The fourth switch is operated to energize the fourth heating element with the AC power, while the first and second switches are operated according to one of the plurality of modulation schedules, such that the cumulative power consumption of the heating element is less than the AC bus power rating of the AC bus.

4. The cooking system according to claim 3, wherein, The first switch and the second switch are thyristors, and the fourth switch is an electromechanical relay.

5. The cooking system according to claim 1, further comprising: The second switch, when actuated, is operable to control the energization of a second heating element located in the heating chamber and associated with the AC bus, so as to conduct the AC power through the second heating element. The instruction, when executed by the controller, is further operable to operate the second switch based on the zero-crossing indication and according to one of the plurality of modulation schedules to energize the second heating element with the alternating current.

6. The cooking system according to claim 5, wherein, One of the multiple modulation schedules defines a first time period based on the number of cycles, defines a first duty cycle based on the first time period, and powers on the first heating element based on the first time period and the first duty cycle.

7. The cooking system according to claim 6, wherein, The first duty cycle is less than or equal to two-thirds of the first time period, wherein, based on the first duty cycle being two-thirds, the first heating element is energized in the first cycle and the last cycle of the first time period.

8. The cooking system according to claim 6, wherein, The first duty cycle is greater than or equal to one-sixth of the first time period, and the number of the periods is greater than or equal to three and less than or equal to fifteen.

9. The cooking system according to claim 8, wherein, The quantity is a multiple of fifteen, such that when the quantity is a multiple of fifteen, the flickering associated with the lamps disposed in the heating chamber is less than the flickering associated with the lamps disposed in the heating chamber when the quantity is fifteen.

10. The cooking system according to claim 6, wherein, One of the multiple modulation schedules defines a second time period based on the number of cycles, the second time period being offset from the first time period by one cycle of the cycles, and the second heating element is energized according to the second time period and at least one of the first duty cycle and the second duty cycle.

11. The cooking system according to claim 10, wherein, The first duty cycle is one-third, and the second duty cycle is two-fifths.

12. The cooking system according to claim 6, wherein, The number of cycles is three, and the first duty cycle alternates between one-third and two-thirds in each first time period.

13. The cooking system according to claim 12, wherein, Based on the first duty cycle being two-thirds, the first heating element is energized in the first cycle of the first time period and the last cycle of the first time period.

14. The cooking system according to claim 13, wherein, One of the multiple modulation schedules defines a second time period, which is five cycles in the cycle and offset from the first time period by one cycle in the cycle, and the second heating element is energized according to the second time period and the first duty cycle.

15. The cooking system according to claim 1, wherein, The first switch is a silicon controlled rectifier (SCR), the controller includes an output associated with the gate of the SCR, and the instruction, when executed by the controller, is further operable to operate the gate.

16. The cooking system according to claim 1, wherein, The zero-crossing circuit includes a diode-transistor-optical coupler.

17. A method for operating a heating element disposed in a heating chamber of a cooking system, the method comprising: AC current with a defined cycle is conducted via an AC bus. Receive a zero-crossing indication based on AC power and defined by a zero-crossing circuit and the AC bus; The controller executes instructions stored in its digital memory, wherein the instructions are in a controller-readable form and include multiple modulation schedules, each of which predefines different energization controls of the heating element, and the instructions are operable to receive the zero-crossing indication when executed by the controller. Actuate the first switch to control the energization of the first heating element in the heating elements; and Based on the zero-crossing indication and according to a selected modulation schedule from the plurality of modulation schedules, the first heating element among the heating elements is energized with the alternating current.

18. The method according to claim 17, wherein, The alternating current is defined for a period of time, and the zero-crossing indication specifies when the alternating current is zero.

19. The method according to claim 18, wherein, The selected modulation schedule defines a first time period based on the number of cycles, defines a first duty cycle based on the first time period, and energizes the first heating element based on the first time period and the first duty cycle.

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