Apparatus and method for cooking at constant temperature using convection heat in oven

Abstract

An apparatus and method for cooking at a constant temperature in an oven including performing a temperature raising operation of operating at least one of at least one heater and at least one circulation fan until a temperature of a preset ratio of a set temperature is reached, continuing the operating at the set temperature for a preset period, and setting an operation level by considering a temperature of the oven at an end of a current period and a temperature of the oven at a start of the current period. The method includes performing a temperature maintaining operation of operating at least one of the at least one heater and the at least one circulation fan for one period according to the set operation level, and repeating the setting of the operation level and the temperature maintaining operation until cooking is completed.

What is claimed is: 
     
         1 . A method of cooking at a constant temperature in an oven, the method comprising:
 performing a temperature raising operation of operating at least one of at least one heater and at least one circulation fan until a temperature of a preset ratio of a set temperature is reached;   continuing the operating of the at least one of the at least one heater and the at least one circulation fan at the set temperature for a preset period;   setting an operation level of the at least one of the at least one heater and the at least one circulation fan by considering a temperature of the oven at an end of a current period and a temperature of the oven at a start of the current period;   performing a temperature maintaining operation of operating the at least one of the at least one heater and the at least one circulation fan for one period according to the operation level set in the setting; and   repeating the setting of the operation level and the temperature maintaining operation until cooking is completed.   
     
     
         2 . The method of  claim 1 , wherein the temperature raising operation comprises:
 setting a first set temperature determined by multiplying the set temperature by the preset ratio; and   operating, the at least one heater and the at least one circulation fan by units of time of a preset first period until the first set temperature is reached, in a preset first combination and in a preset first order for a preset time allocated for each preset first combination.   
     
     
         3 . The method of  claim 1 , wherein the temperature raising operation comprises:
 setting a first set temperature determined by multiplying the set temperature by a preset first ratio and setting a second set temperature determined by multiplying the set temperature by a preset second ratio;   operating, the at least one heater and the at least one circulation fan by units of time of a preset first period until the first set temperature is reached, in a preset first combination and in a preset first order for a preset time allocated for each preset first combination; and   operating, the at least one heater and the at least one circulation fan by units of time of a preset second period until the second set temperature is reached, in a preset second combination and in a preset second order for a preset time allocated for each preset second combination.   
     
     
         4 . The method of  claim 3 , wherein the preset first ratio is lower than the preset second ratio. 
     
     
         5 . The method of  claim 1 , wherein for the operation level,
 the at least one heater and the at least one circulation fan are operated for each operation level in one period, in a preset combination and in a preset order for a preset time allocated for each preset combination.   
     
     
         6 . The method of  claim 1 , wherein the operation level comprises a reference operation level at which the at least one heater and the at least one circulation fan are operated in a preset combination and in a preset order for a preset time allocated for each preset combination, in one period, and
 at the operation level,
 the at least one heater and the at least one circulation fan are operated in the preset combination and in the preset order during the one period, and 
 the preset time allocated for each preset combination at remaining operation levels other than the reference operation level is determined by multiplying the preset time allocated for each preset combination at the reference operation level by a ratio determined by dividing the operation level by the reference operation level. 
   
     
     
         7 . The method of  claim 1 , wherein the operation level comprises a lowest operation level and a highest operation level, and
 the operation level does not fall below the lowest operation level and does not rise above the highest operation level.   
     
     
         8 . The method of  claim 1 , wherein for the temperature maintaining operation,
 an operation time value is calculated by adding a time allocated to the at least one heater according to the operation level and a time stored in a buffer corresponding to the at least one heater, and   in response to the operation time value being less than a preset heating reference value, the at least one heater is not operated in the current period, and the operation time value is stored in the buffer corresponding to the at least one heater, and   in response to the operation time value being greater than or equal to the preset heating reference value, the at least one heater is operated by units of seconds of the operation time value in the current period, and remaining time is stored in the buffer corresponding to the at least one heater.   
     
     
         9 . The method of  claim 1 , wherein the at least one heater comprises:
 a first heater positioned at a top of a cooking chamber of the oven;   a second heater positioned at a bottom of the cooking chamber; and   a third heater positioned on an inner surface of the cooking chamber.   
     
     
         10 . The method of  claim 1 , wherein for the setting of the operation level,
 in response to a calculated operation level exceeding a preset highest operation level as a result of calculating the operation level, the operation level is set to a highest operation level considering the set temperature, a current period temperature which is the temperature of the oven at the end of the current period, and a previous period temperature which is the temperature of the oven at the start of the current period.   
     
     
         11 . The method of  claim 1 , wherein for the setting of the operation level,
 in response to a calculated operation level being less than a preset highest operation level as a result of calculating the operation level, the operation level is set to a lowest operation level considering the set temperature, a current period temperature which is the temperature of the oven at the end of the current period, and a previous period temperature which is the temperature of the oven at the start of the current period.   
     
     
         12 . The method of  claim 1 , wherein for the setting of the operation level,
 the operation level is calculated as follows:
   Next Level=Current Level− K 1 *P−K 2 *D  
 
   where, K1 is a preset proportional coefficient, K2 is a preset differential coefficient, P is a value determined by subtracting the set temperature from a current period temperature which is the temperature of the oven at the end of the current period, and D is a value determined by subtracting a previous period temperature from the current period temperature which is the temperature of the oven at the start of the current period.   
     
     
         13 . The method of  claim 1 , wherein for the setting of the operation level,
 in response to a current period temperature, which is the temperature of the oven at the end of the current period, rising above an upper limit reference value than the set temperature, the operation level is set to an off level for turning off each of the at least one heater.   
     
     
         14 . The method of  claim 1 , wherein for the setting of the operation level,
 in response to a current period temperature which is the temperature of the oven at the end of the current period, falling below an upper limit reference value than the set temperature, the operation level is set to a highest operation level.   
     
     
         15 . The method of  claim 1 , further comprising:
 sensing a core temperature of food; and   in response to the sensed core temperature of the food reaching the set temperature, stopping an operation of the at least one heater and notifying that cooking has been completed.   
     
     
         16 . The method of  claim 15 , wherein for the sensing of the core temperature of the food,
 the core temperature of the food is received and sensed by a probe thermometer inserted into the food.   
     
     
         17 . A method of cooking at a constant temperature in an oven, the method comprising:
 setting a first set temperature determined by multiplying a set temperature by a preset first ratio and setting a second set temperature determined by multiplying the set temperature by a preset second ratio;   operating, at least one heater and at least one circulation fan by units of time of a preset first period until the first set temperature is reached, in a preset first combination and in a preset first order for a preset time allocated for each preset first combination;   operating, the at least one heater and the at least one circulation fan by units of time of a preset second period until the second set temperature is reached, in a preset second combination and in a preset second order for a preset time allocated for each preset second combination;   continuing the operating at least one of the at least one heater and the at least one circulation fan at the set temperature for a preset third period;   setting an operation level of the at least one of the at least one heater and the at least one circulation fan by considering a temperature of the oven at an end of a current third period and a temperature of the oven at a start of the current third period;   performing a temperature maintaining operation of operating the at least one of the at least one heater and the at least one circulation fan for one third period according to the operation level set in the setting; and   repeating the setting of the operation level and the temperature maintaining operation until cooking is completed.   
     
     
         18 . An oven for cooking at a constant temperature using convective heat, comprising:
 a temperature sensor configured to measure a temperature in a cooking chamber;   a first heater on an upper surface of the cooking chamber and configured to generate heat;   a second heater on a lower surface of the cooking chamber and configured to generate heat;   a third heater on a rear wall side of the cooking chamber and configured to generate heat;   a circulation fan disposed around the third heater and configured to spread the heat generated by at least one heater among the first heater, the second heater and the third heater to the cooking chamber to generate convective heat;   a control panel configured to receive a set temperature selected by a user; and   a processor configured to:
 perform a temperature raising operation of operating at least one of the at least one heater and at least one circulation fan until a temperature of a preset ratio of a set temperature is reached, 
 continue the operating of the at least one of the at least one heater and the at least one circulation fan at the set temperature for a preset period, 
 set an operation level of the at least one of the at least one heater and the at least one circulation fan by considering a temperature of the oven at an end of a current period and a temperature of the oven at a start of the current period, until cooking is completed, and 
 perform a temperature maintaining operation of operating the at least one of the at least one heater and the at least one circulation fan for one period according to the operation level set in the setting. 
   
     
     
         19 . The oven of  claim 18 , wherein the processor is configured to, for performing the temperature raising operation,
 set a first set temperature determined by multiplying the set temperature by a preset first ratio and set a second set temperature determined by multiplying the set temperature by a preset second ratio,   operate, the at least one heater and the at least one circulation fan by units of time of a preset first period until the first set temperature is reached, in a preset first combination and in a preset first order for a preset time allocated for each preset first combination, and   operate, the at least one heater and the at least one circulation fan by units of time of a preset second period until the second set temperature is reached, in a preset second combination and in a preset second order for a preset time allocated for each preset second combination.   
     
     
         20 . The oven of  claim 18 , wherein the processor is configured to:
 calculate an operation time value by adding a time allocated to the at least one heater according to the operation level and a time stored in a buffer corresponding to the at least one heater; and   in response to the operation time value being less than a preset heating reference value, not operate the at least one heater in the current period, and store the operation time value in the buffer corresponding to the at least one heater, and   in response to the operation time value being greater than or equal to the preset heating reference value, operate the at least one heater by units of seconds of the operation time value in the current period, and store remaining time in the buffer corresponding to the at least one heater.