Cooking appliance comprising a smoke elimination feature, and method for operating such an appliance

Abstract

A system and method for air frying food which removes or mitigates ‘smoke’ in an oven cavity (12) due to cooking. Fans (24, 58, 68) and catalysts of a cooking appliance (10) are operated for an entirety of a cooking time, while heating elements (16, 18, 20, 52, 54, 56) are not operated during a final portion of the cooking time. For example, the heating elements (16, 18, 20, 52, 54, 56) are not operated for a final five minutes, or 25%, of the cooking time.

Description

BACKGROUND

[0001] The present disclosure is directed to a food cooking method and apparatus. More particularly, the disclosure is directed to an apparatus and method for cooking food via hot air, such as via air fry style cooking.

[0002] Conventionally, air frying refers to the frying of food with reduced or no use of frying oil, potentially reducing the fat content of the resulting food. In this style of cooking, food is cooked not in an oil bath or similar medium, but instead is cooked “in air.” If desired, the food may be pre-coated with a thin layer of oil or oil substitute for the air frying process. Due to rapid circulation of the air by an internal motive element providing a generally consistent, precisely controlled temperature throughout the respective cooking vessel, a resulting food having a crispy exterior can be produced that is similar to a traditionally oil-fried food.

[0003] Such cooking techniques, however, can produce smoke and / or a smoke-like (e.g., a combination of hot-air and grease) exudate in a cooking cavity. This ‘smoke’ may produce unpleased odors or tastes for the food. Further, when a user opens the cavity to retrieve the food, the smoke can escape into a kitchen or other room and be unpleasant for individuals nearby.BRIEF SUMMARY

[0004] According to one example of the present disclosure a cooking appliance comprises: a cooking cavity; a heating element; a fan configured to circulate air within the cooking cavity; and a controller configured to: operate the heating element to regulate a cooking temperature within the cooking cavity during an operative cooking time of a total cooking time, the total cooking time comprising the operative cooking time and thereafter a smoke-elimination time, operate the fan during the smoke-elimination time, and stop operation of all heating elements of the cooking appliance at a conclusion of the operative cooking time such that none of the heating elements of the cooking appliance are operated during the entire smoke-elimination time.

[0005] In various embodiments of the above example, an end of the smoke-elimination time is an end of the total cooking time; the heating element is a convection heating element, and the fan is a convection fan; the cooking appliance further comprises: a catalyst and heater in an exhaust flue of the cooking appliance, wherein the controller is configured to operate the heater during the smoke-elimination time; the cooking appliance further comprises: a vent fan, wherein said controller is further configured to operate the vent fan during said smoke-elimination time effective to provide a cushion of thermal insulation surrounding or adjacent to an exterior of the cooking cavity within the appliance; the smoke-elimination time is at least twenty-five percent of the total cooking time; the smoke-elimination time is at least five minutes; the cooking appliance further comprises: a user interface configured to receive a user selection to activate an air fry cooking mode, a cooking temperature, and the total cooking time as inputs from a user, wherein the regulated cooking temperature within the cooking cavity is the received cooking temperature; and / or the cooking appliance further comprises: a user interface configured to receive a user selection to activate an air fry cooking mode and an indication of a food item to be cooked by the cooking appliance, wherein the controller is further configured to determine the regulated cooking temperature and / or said total cooking time based on at least the indication of the food item.

[0006] According to another example of the present disclosure, a cooking method for a cooking appliance comprising a cooking cavity, a heating element, and a fan configured to circulate air within the cooking cavity, comprises: operating the heating element to regulate a cooking temperature within the cooking cavity during an operative cooking time of a total cooking time, the total cooking time comprising the operative cooking time and thereafter a smoke-elimination time; operating the fan during the smoke-elimination time, and stopping operation of all heating elements of the cooking appliance at a conclusion of the operative cooking time such that none of the heating elements of the cooking appliance are operated during the entire smoke-elimination time.

[0007] In various embodiments of the above example, an end of the smoke-elimination time is an end of the total cooking time; the heating element is a convection heating element, and the fan is a convection fan; said cooking appliance further comprises a catalyst and heater in an exhaust flue of the cooking appliance, and the method further comprises: operating the heater during the smoke-elimination time; said cooking appliance further comprising a vent fan and the method further comprises: operating the vent fan during said smoke-elimination time effective to provide a cushion of thermal insulation surrounding or adjacent to an exterior of the cooking cavity within the appliance; the smoke-elimination time is at least twenty-five percent of the total cooking time; the smoke-elimination time is at least five minutes; the method further comprises: receiving a user selection to activate an air fry cooking mode, a cooking temperature, and the total cooking time as inputs from a user, wherein the regulated cooking temperature within the cooking cavity is the received cooking temperature; and / or the method further comprises: receiving a user selection to activate an air fry cooking mode and an indication of a food item to be cooked by the cooking appliance; and determining said regulated cooking temperature and / or said total cooking time based on at least the indication of the food item.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0008] FIG. 1 schematically illustrates a side cross-section of a cooking appliance used for air fry style cooking;

[0009] FIG. 2 schematically illustrates a control system of the cooking appliance of FIG. 1;

[0010] FIG. 3 schematically illustrates a side cross-section of another cooking appliance used for air fry style cooking; and

[0011] FIG. 4 illustrates an example method for air fry cooking according to the present disclosure.DETAILED DESCRIPTION

[0012] The present disclosure relates to a method and apparatus for cooking using air as the cooking medium in a kitchen range, for example air frying a food item using a kitchen range, the reduces or eliminates smoke at the end of cooking.

[0013] The methods of the present disclosure may be implemented by cooking appliances, such as a kitchen range or oven, microwave appliance, or countertop cooking appliance. Rather than using a traditional oil bath, hot air, and in some aspects continuously moving hot air, is used as a cooking medium. A food item can be fried using a minimum of, or no, oil pre-applied as a coating to the food item, resulting in a healthier, cleaner and more efficient frying of the food item. Such appliances may be those described in U.S. Pat. No. 10,561,277, the entirety of which is incorporated herein by reference.

[0014] According to one example, the appliance may be a gas or electric kitchen range or oven having an oven cavity with heating elements (e.g., bake, broil, and convection elements) and other elements such as convection fans, cooling fans, and / or a catalytic oven exhaust cleaner (an “air guard”). A controller (e.g., having a processor and memory) controls the power to the elements of the appliance. A temperature sensor may also be disposed in a cooking cavity of the appliance for measuring the temperature of the cavity and providing the measured temperature as a feedback signal to the controller. Utilizing these and other elements, the controller may operate the cooking appliance in accordance with a cooking process, such as an air fry cooking process. These cooking processes may utilize a convection fan of the convection system to provide a generally uniform convective air-temperature throughout the associated oven cavity, in combination with temperature and / or time controlled heating stages. During at least one of the stages, the convection fan and two or more of the heating elements may be operated according to either conventional hysteresis temperature control or a proportional-integral-derivative (PID) temperature control, in either case based on temperature feedback measured in the cavity.

[0015] With reference to FIG. 1, a cooking appliance 10, such as a kitchen range, is illustrated having the above-identified fan and heating elements for heating an interior oven cavity 12 defined by an appliance cabinet 14. A food item 15 to be cooked is illustrated within the oven cavity 12. The heating elements for heating the oven cavity 12 and cooking the food item 15 include a broil heating element 16, a bake heating element 18, and a convection heating element 20. The broil heating element 16 is disposed at (i.e. in or adjacent) an upper portion of the oven cavity 12. The bake heating element 18 is disposed at (i.e. in or adjacent) a lower portion of the oven cavity 12, generally opposite the broil heat element 16. The convection heating element 20 is disposed at (i.e. in or adjacent) a back portion of the oven cavity 12.

[0016] The convection heating element 20 is part of a convection heating system 22 including the convection heating element 20 and an associated motive element for moving heated air, such as the convection fan 24. With respect to the illustrated fan 24, rotation of an impeller of the fan 24 enables distribution of heat provided by the convection heating element 20, and also by the broil and bake heating elements 16 and 18, throughout the oven cavity 12. Employing a convection fan to circulate air in a small, confined space such as an oven produces substantially uniform air distribution, which enables saturation of the cavity 12 with evenly heated air. While the convection fan 24 is shown as being disposed adjacent to the convection heating element 20, the fan 24, or another fan, may be otherwise disposed elsewhere within or relative to the oven cavity, such as not being specifically associated with the convection heating element 20. One or more additional heating elements may be provided in other embodiments, and / or one or more of the heating elements 16, 18 and 20 may be omitted.

[0017] The cooking appliance may also have an exhaust flue 26. In the example of FIG. 1, the exhaust flue 26 is located at a top of the oven cavity 12, to conduct hot air out of an exhaust outlet located between a rear control panel (e.g., where control system 30 and user interface 40 are located, discussed below) and the appliance cabinet 14. The flue 26 may have a vent fan and a catalyst heated by a heater thereof for filtering air that passes therethrough, the fan drawing air from the cavity 12 through the heated catalyst prior to being exhausted. The catalyst may be located in the flue nearer to the cavity 12 than the exhaust outlet to ensure all exhausted air passes therethrough. For appliances in which the control panel is located on a front of the cabinet 14 (rather than at a rear as in FIG. 1), the exhaust outlet may be located at a rear of the cabinet14.

[0018] The cooking appliance 10 also includes a control system 30, which while illustrated at an upper-rear location of the appliance 10 may be otherwise suitably located in other embodiments. The control system 30 is schematically illustrated in FIG. 2 and is provided for controlling operation of the heating elements 16, 18, and 20 and of the fan 24. As will be understood by one having ordinary skill in the art, the control system 30 of the cooking appliance 10 can be configured to operate any one of the heating elements 16, 18 and 20 and the fan 24 separately from one another or in conjunction with any one or more of the other of the heating elements 16, 18 and 20 and the fan 24. To provide this control, the control system 30 is communicatively connected to each of the heating elements 16, 18, and 20, to the fan 24, and to at least one sensor 32 (FIG. 1) disposed in the oven cavity 12 to monitor the temperature of the oven cavity 12. The control system 30 includes at least a processor 34 and a storage 36, such as a memory, which in other embodiments may be integral with the processor 34.

[0019] In other examples, such as that illustrated in FIG. 3, the cooking appliance may be a microwave appliance 50 having three calrod heating elements 52, 54, and 56. The first calrod heating element 52 corresponds to a broil element (e.g., element 16 of FIG. 1) and the second calrod element 54 corresponds to a bake element (e.g., element 18 of FIG. 1). The third calrod element 56 corresponds to a convection element (e.g., element 20 of FIG. 1) that is part of a convection heating system 60 having a convection fan 58. In such embodiments, the controller of the microwave appliance controls one or more of the three calrod heating elements 52, 54, 56 and the convection fan 58 to be operated alone (without operating a magnetron 62 of the microwave) during an air-fry cooking process to cook a food item 64 in the microwave cavity 66.

[0020] Additionally, the microwave appliance 50 may include a vent fan 68 for venting air from the cavity 68. As shown in FIG. 3, the vent fan 68 is configured to draw cooking fumes from the cavity 68 through a filter 70 to be exhausted from the appliance 50 by a flue 72. However, in other embodiments such as with ‘over-the-range’ microwave appliances, the vent fan 68 may be configured to draw fumes a cook surface located below the microwave appliance. When operated during an air fry cooking method of the microwave appliance, the vent fan 68 may additionally (or alternatively) serve as a cooling fan by drawing in cool (room temperature) ambient air through a casing of the microwave appliance, effectively to provide a cushion of thermal insulation surrounding or adjacent to the exterior of the cooking cavity within the appliance. Such cooling may protect electronics of the microwave appliance from over-heating, and / or limit the temperature of external surfaces or other elements of the microwave appliance that are exposed to and may be touched by a user (e.g., a door). Such overheating may be the result of operating the heating elements at a sufficient power to effectuate air frying.

[0021] Initiation of the functionality described herein (and others associated with the cooking appliance) may be caused by a user activating an input of a user interface 40 of the control system 30. The user interface 40 may further include a display, auditory element or tactile element, for providing one or more of visual, audible or tactile feedback to the user. In some embodiments the user may alternatively or additionally interact with the appliance remotely, for example via an email, a mobile device, and the like.

[0022] With reference to FIG. 4, the method of the present disclosure begins when a user selects an ‘Air Fry’ cooking mode 80 before or after placing the food item 15 in the oven cavity 12. Once the ‘Air Fry’ mode is selected, the user may be prompted to input or select a desired food temperature 82. The user may then be prompted to input or select a desired cook time 84, for example, as part of a ‘Time Bake’ operation in which the appliance automatically stops cooking at the expiration of the input or selected time. In other embodiments, the user may simply be prompted to enter an indication of the food to be cooked (e.g., chicken wings). In these instances, the controller may determine an appropriate temperature and / or cook time based on the input food. For example, the controller may be pre-programmed to utilize (or programmed to calculate) a temperature of 450° F. and a time of 35 minutes when the user indicates the food being cooked is chicken wings. At step 86, the air fry cooking process is executed by the appliance by controlling the heating and other elements therein. The cooking process executed at step 86 may be a multiple stage process, such as that described in the above-noted '277 patent, whereby the elements of the appliance are operated (e.g., energized and / or de-energized for given time periods) according to the cooking process.

[0023] The cooking process proceeds for an operative cooking time equal to the cook time indicated in step 84, less a predetermined smoke-elimination time for removing (or otherwise mitigating) smoke. At the expiration of the operative cooking time, the appliance (via control system 30) controls the heating elements therein to stop operating at step 88, while continuing to operate the fan(s) of the appliance (such as a convection fan or vent fan) and the heater for the catalyst at step 88. Although the heating elements are not operated, the food may still continue to cook due to latent heat from the heating elements and the temperature inside the cooking cavity. However, the amount of additional smoke created due to the high temperatures and added heat from the heating elements themselves is mitigated or eliminated during the predetermined time. Moreover, the fans (including the vent and convection fans) can help cool the food and control air flow through the catalyst and exhaust flue to remove any existing smoke from the cavity before it is opened by a user. By including the predetermined time for smoke evacuation at the conclusion of cooking within the total cook time, rather than appending it at the end of that cook time, the total time for cooking experienced by the user remains unchanged while ensuring the food item 15 is still fully cooked.

[0024] According to one embodiment, the smoke-elimination time may be relative to the total cooking time. For example, the smoke-elimination time may be at least 25% of the cook time indicated in step 84. This smoke-elimination time (and thus the period during which the heating elements are not operated, while the fans and catalyst continue to be operated in steps 88 and 90) are part of the total cook time indicated in step 84, rather than a separate time period added at the end of cooking.

[0025] For example, for a total cook time of 20 min (e.g. which can be counted-down by the appliance display and on which the user will rely), the heating elements are operated according to the cooking process at step 86 for 15 min (75% of the 20 min cook time) and are not operated for the final 5 min (25% of the 20 min cook time). The fans and catalyst continue to be operated for that final 5 min. In this example, the operative cooking time is 15 min, while the smoke-elimination time is 5 min. According to another embodiment, the operation time of the heating elements may be an absolute, rather than relative, time. For example, the smoke-elimination time may be at least five minutes, rather than a percentage of the cooking time. The use of a relative time such as 25% may be beneficial for shorter cook times, where an absolute time of, for example, five minutes may represent a significant proportion of the total cooking time and prevent the food from being fully cooked.

[0026] In short, the cooking processes according to the present disclosure can reduce or eliminate smoke in the cooking cavity at the end of cooking by stopping operation of the heating elements for a predetermined period of time at the end of the cooking process, while leaving the convection and / or vent fan(s) on. These fans help air flow through the heated catalyst and exhaust flue of the cooking appliance, thus removing smoke in the cavity prior to it being opened by a user. In other words, for a predetermined period of time at the end of the cooking process, one or more fans of the cooking appliance are used to draw smoke in the cavity through the flue and the catalyst, so that the smoke does not instead escape when the user opens the oven door.

[0027] At an expiration of the predetermined time (and thus the total cook time), the operation of all elements of the cooking appliance other than the heating elements (for which operation was already stopped at the start of the smoke-elimination time) may be stopped either automatically or by the user, and the appliance may sound a notification to a user to indicate that cooking is complete. The user may then remove the cooked food from the cooking cavity, without smoke eluting from the cavity into the ambient environment.

[0028] The efficacy of the above-described method has been proven via laboratory testing. Specifically, alarmed ionization and photoelectric smoke detectors were placed at three, six, and ten feet from a floor-standing test oven, at a height of 72 inches. Chicken wings were then cooked in the test oven in two ways: first, preheated to 450° F. and then cooked for 35 min using a traditional ‘Air Fry’ cooking method (i.e., a control); and second, preheated to 450° F. and then cooked for 35 min using the ‘Air Fry’ cooking method with the smoke removal technique described herein, using a smoke-elimination time of 25% of total cook time (i.e., the final 8 min and 45 sec of cooking). Cooking according to the conventional method caused all three alarms to sound (indicating that smoke particles had reached the detectors) after the door of the test oven was opened following cooking. In contrast, when the chicken wings were cooked according to the method described herein, none of the alarms sounded.

[0029] While various features are presented above, it should be understood that the features may be used singly or in any combination thereof. Further, it should be understood that variations and modifications may occur to those skilled in the art to which the claimed examples pertain.

Claims

1. A cooking appliance comprising:a cooking cavity;a heating element;a fan configured to circulate air within the cooking cavity; anda controller configured to:operate the heating element to regulate a cooking temperature within the cooking cavity during an operative cooking time of a total cooking time, the total cooking time comprising the operative cooking time and thereafter a smoke-elimination time,operate the fan during the smoke-elimination time, andstop operation of all heating elements of the cooking appliance at a conclusion of the operative cooking time such that none of the heating elements of the cooking appliance are operated during the entire smoke-elimination time.

2. The cooking appliance of claim 1, wherein an end of the smoke-elimination time is an end of the total cooking time.

3. The cooking appliance of claim 1, wherein the heating element is a convection heating element, and the fan is a convection fan.

4. The cooking appliance of claim 1, further comprising:a catalyst and heater in an exhaust flue of the cooking appliance,wherein the controller is configured to operate the heater during the smoke-elimination time.

5. The cooking appliance of claim 1, further comprising:a vent fan,wherein said controller is further configured to operate the vent fan during said smoke-elimination time effective to provide a cushion of thermal insulation surrounding or adjacent to an exterior of the cooking cavity within the appliance.

6. The cooking appliance of claim 1, further comprising:a vent fan,wherein said controller is further configured to operate the vent fan during said smoke-elimination time effective to exhaust air from the cooking cavity.

7. The cooking appliance of claim 1, wherein the smoke-elimination time is at least twenty-five percent of the total cooking time.

8. The cooking appliance of claim 1, wherein the smoke-elimination time is at least five minutes.

9. The cooking appliance of claim 1, further comprising:a user interface configured to receive a user selection to activate an air fry cooking mode, a cooking temperature, and the total cooking time as inputs from a user,wherein the regulated cooking temperature within the cooking cavity is the received cooking temperature.

10. The cooking appliance of claim 1, further comprising:a user interface configured to receive a user selection to activate an air fry cooking mode and an indication of a food item to be cooked by the cooking appliance,wherein the controller is further configured to determine the regulated cooking temperature and / or said total cooking time based on at least the indication of the food item.

11. A cooking method for a cooking appliance comprising a cooking cavity, a heating element, and a fan configured to circulate air within the cooking cavity, the method comprising:operating the heating element to regulate a cooking temperature within the cooking cavity during an operative cooking time of a total cooking time, the total cooking time comprising the operative cooking time and thereafter a smoke-elimination time;operating the fan during the smoke-elimination time, andstopping operation of all heating elements of the cooking appliance at a conclusion of the operative cooking time such that none of the heating elements of the cooking appliance are operated during the entire smoke-elimination time.

12. The cooking method of claim 11, wherein an end of the smoke-elimination time is an end of the total cooking time.

13. The cooking method of claim 11, wherein the heating element is a convection heating element, and the fan is a convection fan.

14. The cooking method of claim 11, said cooking appliance further comprising a catalyst and heater in an exhaust flue of the cooking appliance, the method further comprising:operating the heater during the smoke-elimination time.

15. The cooking method of claim 11, said cooking appliance further comprising a vent fan, the method further comprising:operating the vent fan during said smoke-elimination time effective to provide a cushion of thermal insulation surrounding or adjacent to an exterior of the cooking cavity within the appliance.

16. The cooking method of claim 11, said cooking appliance further comprising a vent fan, the method further comprising:operating the vent fan during said smoke-elimination time effective to exhaust air from the cooking cavity.

17. The cooking method of claim 11, wherein the smoke-elimination time is at least twenty-five percent of the total cooking time.

18. The cooking method of claim 11, wherein the smoke-elimination time is at least five minutes.

19. The cooking method of claim 11, further comprising:receiving a user selection to activate an air fry cooking mode, a cooking temperature, and the total cooking time as inputs from a user,wherein the regulated cooking temperature within the cooking cavity is the received cooking temperature.

20. The cooking method of claim 11, further comprising:receiving a user selection to activate an air fry cooking mode and an indication of a food item to be cooked by the cooking appliance; anddetermining the regulated cooking temperature and / or said total cooking time based on at least the indication of the food item.

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