Air fry cooking method and apparatus
A method is disclosed for cooking food in an oven cavity, where air is the cooking medium. Using a predetermined cooking algorithm, a temperature of the oven cavity is adjusted in a plurality of temperature and/or time regulated cooking stages. An initial pre-heat stage targets a first target temperature including a user-selected oven cavity temperature plus a first offset. A subsequent post-heat stage targets a second target temperature including the user-selected temperature plus a second offset different from the first offset. Two or more heating elements and a fan are operated during the post-heat stage according to a duty cycle controlled via a hysteresis temperature control algorithm or a PID temperature control algorithm.
1 . A cooking appliance, comprising:
an oven cavity;
a plurality of heating elements for heating the oven cavity; and
a controller adapted to separately control operation of each heating element of the plurality of heating elements according to hysteresis control or proportional-integral-derivative (PID) control, wherein the controller is configured to:
receive a user selection to activate a cooking mode including at least a first heating stage and a second heating stage,
receive a setpoint temperature from a user,
operate one or more of said plurality of heating elements during the first heating stage based on a first target temperature, wherein the first target temperature is offset from the setpoint temperature such that the first target temperature is equal to the setpoint temperature adjusted by a first offset, and
operate one or more of said plurality of heating elements during the second heating stage based on a second target temperature, wherein the second target temperature is offset from the setpoint temperature such that the second target temperature is equal to the setpoint temperature adjusted by a second offset.
2 . The cooking appliance of claim 1 , wherein the plurality of heating elements includes at least a bake heating element and a convection heating element.
3 . The cooking appliance of claim 1 , wherein the controller is configured to operate according to hysteresis control in the first heating stage and/or second heating stage.
4 . The cooking appliance of claim 1 , wherein the controller is configured to operate according to PID control in the first heating stage and/or second heating stage.
5 . The cooking appliance of claim 1 , further comprising a body configured to be disposed adjacent a countertop, the body having an upper surface that is configured to be generally level with the countertop.
6 . The cooking appliance of claim 1 , wherein the cooking mode includes a preheat stage prior to the first heating stage, wherein the first offset of the first heating stage is non-zero.
7 . The cooking appliance of claim 1 , wherein the controller is configured such that each heating element of said plurality of heating elements is operated at a constant power during operation thereof.
8 . The cooking appliance of claim 1 , wherein the controller is configured to vary runtimes of the plurality of heating elements to thereby provide the first and second target temperatures during the first and second heating stages, respectively.
9 . The cooking appliance of claim 1 , wherein the first offset and second offset are different from each other, such that the first target temperature of the first heating stage and the second target temperature of the second heating stage are different from each other.
10 . The cooking appliance of claim 1 , wherein:
during the first heating stage, the controller is configured to operate one or more of said plurality of heating elements according to hysteresis control based on a first upper temperature limit that is greater than the first target temperature, and a first lower temperature limit that is less than the first target temperature, and
during the second heating stage, the controller is configured to operate one or more of said plurality heating elements according to hysteresis control based on a second upper temperature limit that is greater than the second target temperature, and a second lower temperature limit that is less than the second target temperature.
11 . A cooking appliance, comprising:
an oven cavity;
a plurality of heating elements for heating the oven cavity, the plurality of heating elements comprising a bake heating element and a convection heating element;
a convection fan for circulating heated air within the oven cavity; and
a controller adapted to separately control operation of the convection fan and each heating element of the plurality of heating elements according to hysteresis control or proportional-integral-derivative (PID) control, wherein the control is configured to:
receive a user selection to activate an air fry mode for frying an item in the oven cavity, the air fry mode including at least a first heating stage and a second heating stage,
receive a setpoint temperature from a user,
separately operate the convection fan and one or more of the plurality of heating elements during the first heating stage based on a first target temperature, wherein the first target temperature is offset from the setpoint temperature such that the first target temperature is equal to the setpoint temperature adjusted by a first offset, and
separately operate the convection fan and one or more of said plurality of heating elements during the second heating stage based on a second target temperature, wherein the second target temperature is offset from the setpoint temperature such that the second target temperature is equal to the setpoint temperature adjusted by a second offset,
wherein the controller is configured execute the second heating stage for an indefinite period of time.
12 . The cooking appliance of claim 11 , wherein the controller is configured to prompt the user to insert food to be cooked into the oven cavity prior to the second heating stage.
13 . The cooking appliance of claim 11 , wherein the controller is configured to operate the convection fan during the entire indefinite period of time of the second heating stage.
14 . The cooking appliance of claim 11 , wherein the controller is configured to prompt the user to insert food to be cooked into the oven cavity prior to operating the convection fan for said indefinite period of time.
15 . A method for cooking food with a cooking appliance having an oven cavity and a plurality of heating elements for heating the oven cavity, the method comprising:
receiving a user selection to activate a cooking mode including at least a first heating stage and a second heating stage;
receiving a setpoint temperature from a user; and
separately controlling operation of one or more of said plurality of heating elements according to hysteresis control or proportional-integral-derivative (PID) control during the first heating stage based on a first target temperature, wherein the first target temperature is offset from the setpoint temperature such that the first target temperature is equal to the setpoint temperature adjusted by a first offset; and
separately controlling operation of one or more of said plurality of heating elements according to hysteresis control or proportional-integral-derivative (PID) control during the second heating stage based on a second target temperature, wherein the second target temperature is offset from the setpoint temperature such that the second target temperature is equal to the setpoint temperature adjusted by a second offset.
16 . The method of claim 15 , wherein the plurality of heating elements are operated according to hysteresis control in the first heating stage and/or second heating stage.
17 . The method of claim 15 , wherein the plurality of heating elements are operated according to PID control in the first heating stage and/or second heating stage.
18 . The method of claim 15 , wherein each of the plurality of heating elements is operated at a constant power during activation thereof.
19 . The method of claim 15 , wherein the first and second offsets differ from one another by at least 40%.
20 . The method of claim 15 , wherein the first offset and second offset are predetermined.
21 . The method of claim 15 , wherein the first offset and second offset are determined based on at least one factor from a group of factors consisting of:
a cavity thermal mass or heat capacity of the oven cavity,
heating rate(s) of the actuated heating element(s),
whether a door of the oven cavity is cycled open or not,
insulation or insulation efficiency of the oven cavity,
a rate of thermal loss of the oven cavity,
air circulation within the oven cavity, and
the setpoint temperature.
22 . A method for air frying a food item with a cooking appliance comprising an oven cavity, a convection fan, and a plurality of heating elements for heating the oven cavity, the plurality of heating elements including a bake heating element and a convection heating element, the method comprising:
receiving a user selection to activate an air frying mode including at least a first heating stage and a second heating stage;
receiving a setpoint temperature from a user;
separately controlling operation of each of the bake heating element, the convection heating element, and the convection fan according to hysteresis control or proportional-integral-derivative (PID) control during the first heating stage based on a first target temperature, wherein the first target temperature is offset from the setpoint temperature such that the first target temperature is equal to the setpoint temperature adjusted by a first offset; and
separately controlling operation of the bake heating element, the convection heating element, and the convection fan according to hysteresis control or proportional-integral-derivative (PID) control during the second heating stage based on a second target temperature, wherein the second target temperature is offset from the setpoint temperature such that the second target temperature is equal to the setpoint temperature adjusted by a second offset,
wherein the second heating stage is continued for an indefinite period of time.
23 . The method of claim 22 , further comprising prompting the user to insert food to be cooked into the oven cavity prior to the second heating stage.
24 . The method of claim 22 , further comprising prompting the user to insert food to be cooked into the oven cavity prior to operating the convection fan for the indefinite period of time.