Range hood

Abstract

To provide a range hood that can automatically start driving of a blower when a heat cooker is brought into a heated state and can prevent the blower from automatically starting operation due to erroneous detection when the heat cooker is not in the heated state.SOLUTION: A range hood includes: a blower 22; and a temperature sensor 25 for detecting temperature on an upper side of a heat cooker 10. The range hood has an automatic operation mode of automatically starting the driving of the blower 22 when a temperature gradient of a detected temperature by the temperature sensor 25 is equal to or more than a first threshold α1 that indicates a temperature rising state and the detected temperature by the temperature sensor 25 is equal to or more than a preset first prescribed temperature T1 and then, a prescribed condition is met.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a range hood that exhausts oily smoke generated by cooking with a cooking appliance to the outdoors, etc. [Background technology]

[0002] Range hoods are sometimes used to start the fan when the cooking appliance is turned on to start cooking, and to exhaust the oily smoke generated by the cooking appliance to the outdoors, etc. Therefore, a range hood has been proposed that automatically starts and stops the fan when the cooking appliance is turned on to start cooking. For example, as disclosed in Patent Document 1, a range hood has been proposed in which a device for detecting the temperature above a cooking appliance is provided in the hood body, and the fan is automatically started and stopped depending on the detected temperature. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-121751 A Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of range hood, the fan starts operating based only on the temperature above the cooking appliance, so there are cases where the range hood mistakenly detects that the cooking appliance is heating even when cooking is not being performed, and starts operating the fan. For example, when food that has been heated using a heater other than a cooking device such as a microwave oven is moved onto the cooking device, the temperature on the cooking device rises due to the food, so the range hood determines that the cooking device is heating and automatically starts operating the fan. However, since the cooking device is not actually heated, there is no need to operate the fan, resulting in unnecessary consumption of electricity.

[0005] The present invention has been made to solve the above-mentioned problems, and its object is to provide a range hood that can automatically start operating a fan when a cooking appliance is in a heated state, and can prevent the fan from automatically starting operating due to erroneous detection when the cooking appliance is not in a heated state. [Means for solving the problem]

[0006] The range hood of the present invention is a range hood equipped with a blower and a temperature sensor for detecting the temperature above a cooking appliance, and is characterized in having an automatic operation mode that drives the blower when the temperature gradient of the temperature detected by the temperature sensor satisfies a predetermined condition after the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a first threshold value indicating a temperature rising state and the temperature detected by the temperature sensor is equal to or greater than a set first predetermined temperature.

[0007] In the range hood of the present invention, the predetermined condition can be that a temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value that indicates a temperature rising state. With this configuration, when the cooking appliance is in a heating state, the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than the second threshold value, satisfying the predetermined condition, so that the blower can automatically start to be driven. In addition, if a heated food item is moved onto the cooking appliance when the cooking appliance is not in a heated state, a continuous temperature rise does not occur because the cooking appliance is not in a heated state, and the temperature gradient of the temperature detected by the temperature sensor is below the second threshold value and does not satisfy the specified condition, so that the blower 22 does not automatically start operating. Therefore, automatic starting of the blower due to a false detection when the cooking appliance is not in a heated state can be prevented, and the blower is not operated unnecessarily.

[0008] In the range hood of the present invention, the specified condition may be that the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value indicating a temperature rising state for a set specified period of time. With this configuration, a continuous temperature rise does not occur when the cooking appliance is not in a heating state, so that automatic start of operation of the blower due to erroneous detection when the cooking appliance is not in a heating state can be prevented.

[0009] In the range hood of the present invention, the specified condition may be that the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value indicating a temperature rising state for a specified number of times or more. With this configuration, a continuous temperature rise does not occur when the cooking appliance is not in a heating state, so that automatic start of operation of the blower due to erroneous detection when the cooking appliance is not in a heating state can be prevented.

[0010] In the range hood of the present invention, the specified condition may be that the temperature gradient of the temperature detected by the temperature sensor does not continuously fall below a second threshold value indicating a temperature rising state during a set specified period of time. With this configuration, even if the temperature temporarily drops during the temperature rise after entering a heated state due to some factor, the fan can be automatically started as long as the temperature gradient of the detected temperature by the temperature sensor does not continuously fall below the set second threshold value, thereby preventing the fan from being unable to be automatically started due to erroneous detection.

[0011] In the range hood of the present invention, the specified condition can be that the temperature gradient of the temperature detected by the temperature sensor does not fall below a second threshold indicating a temperature rising state consecutively, and the temperature gradient of the temperature detected by the temperature sensor is above a second threshold a specified number of times. With this configuration, even if the temperature temporarily drops during the temperature rise after entering a heated state due to some factor, the blower can be automatically started as long as the temperature gradient of the detected temperature by the temperature sensor does not fall continuously below the set second threshold value, thereby preventing the blower from being unable to start due to erroneous detection.

[0012] In the range hood of the present invention, the automatic operation mode can be such that, during determination of the specified conditions, the temperature gradient of the detected temperature of the temperature sensor exceeds a third threshold indicating a temperature rising state a specified number of times, and the third threshold can be a threshold that results in a higher temperature rise than the second threshold indicating a temperature rising state used under the specified conditions. With this configuration, when the cooking appliance is in a heating state but the temperature on the cooking appliance detected by the temperature sensor repeatedly rises and falls suddenly, making it impossible to stably detect the temperature and therefore unable to meet the specified conditions, the blower can be automatically started.

[0013] In the range hood of the present invention, the automatic operation mode has a third predetermined temperature higher than the first predetermined temperature, and when the temperature gradient of the temperature detected by the temperature sensor exceeds the set third threshold during the determination of the specified conditions, the temperature before the temperature rise is stored, and the blower is driven when the temperature currently stored exceeds the previously stored temperature a predetermined number of times while the temperature detected by the temperature sensor remains higher than the third predetermined temperature. With this configuration, even if the cooking appliance is in a heating state but the temperature on the cooking appliance detected by the temperature sensor repeatedly rises and falls suddenly, making it impossible to stably detect the temperature and thus failing to meet the specified conditions, the blower can be automatically started. Furthermore, when heated food is moved onto the cooking device without turning the cooking device on to a heating state, the automatic start of operation of the blower 22 can be prevented when the temperature on the cooking device rises or falls suddenly due to stirring the food or removing the lid from the food.

[0014] The range hood of the present invention can have the following configuration. (1) A range hood equipped with a blower and a temperature sensor for detecting the temperature above a cooking appliance, characterized in that the range hood has an automatic operation mode in which the blower is driven when the temperature gradient of the temperature detected by the temperature sensor satisfies a predetermined condition after the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a first threshold value indicating a temperature rising state and the temperature detected by the temperature sensor is equal to or greater than a first predetermined temperature.

[0015] (2) The range hood according to (1), wherein the predetermined condition is that the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value indicating a temperature rise state. (3) A range hood as described in (1) or (2), characterized in that the specified condition is that the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value indicating a temperature rising state for a set specified period of time. (4) A range hood described in any one of (1) to (3), characterized in that the specified condition is that the temperature gradient of the temperature detected by the temperature sensor is greater than or equal to a second threshold value indicating a temperature rise state for a specified number of consecutive times or more. (5) A range hood described in any of (1) to (4), characterized in that the specified condition is that the temperature gradient of the detected temperature of the temperature sensor does not continuously fall below a second threshold value indicating a temperature rising state during a set specified period of time.

[0016] (6) A range hood described in any of (1) to (5), characterized in that the specified condition is that the temperature gradient of the temperature detected by the temperature sensor does not fall below a second threshold indicating a temperature rising state consecutively, and the temperature gradient of the temperature detected by the temperature sensor is above the second threshold a specified number of times or more. (7) A range hood described in any of (1) to (6), characterized in that the automatic operation mode drives the blower when the temperature gradient of the detected temperature of the temperature sensor exceeds a third threshold indicating a temperature rising state a predetermined number of times during determination of the specified conditions, and the third threshold is a threshold that results in a higher temperature rise than the second threshold indicating a temperature rising state used under the specified conditions.

[0017] (8) A range hood as described in any of (1) to (7), characterized in that the automatic operation mode has a third predetermined temperature higher than the first predetermined temperature, and when the temperature gradient of the temperature detected by the temperature sensor exceeds the set third threshold during the determination of the predetermined conditions, a state in which the temperature currently stored exceeds the previously stored temperature or the temperature before the temperature rise is stored, and the state in which the temperature detected by the temperature sensor remains higher than the third predetermined temperature continues, and the blower is driven when the temperature currently stored exceeds the previously stored temperature a predetermined number of times. Effect of the Invention

[0018] According to the range hood of the present invention, the blower can be automatically started when the cooking appliance is in a heated state, and automatic starting of the blower due to erroneous detection when the cooking appliance is not in a heated state can be prevented. [Brief description of the drawings]

[0019] [Figure 1] 1 is a schematic explanatory diagram showing an embodiment of a cooking device and a range hood of the present invention. [Diagram 2] 1 is a graph showing changes in detected temperature in a normal temperature state during cooking according to the present invention. [Diagram 3] 1 is a graph showing the change in detected temperature when a heated food product of the present invention is moved onto a cooking device. [Figure 4] 1 is a graph showing changes in detection temperature for an abnormal temperature state during cooking according to the present invention. [Diagram 5] 10 is a graph showing changes in detected temperature when the flame of the cooking device of the present invention is directly detected. [Figure 6] 4 is a flowchart showing a first operation for automatically starting driving the blower of the present invention. [Figure 7] 6 is a flowchart showing a second operation for automatically starting driving the blower of the present invention. [Figure 8] 10 is a flowchart showing a third operation for automatically starting driving the blower of the present invention. [Figure 9]13 is a flowchart showing a fourth operation for automatically starting driving the blower of the present invention. [Figure 10] 5 is a flowchart showing an operation of automatically stopping the blower of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] An embodiment of the range hood of the present invention will be described. An embodiment of a cooking device and a range hood will be described with reference to FIG. 1. FIG. 1 is a schematic explanatory diagram showing an embodiment of a cooking device and a range hood. Cooking device 10 includes heating section 11, switch 12, heating section control section 13, and transmission section 14. By operating switch 12 to send a heating signal or a stop signal to heating section control section 13, heating section control section 13 heats or stops heating section 11, and transmits the heating signal or the stop signal from transmission section 14 using infrared rays. By operating switch 12, the amount of heat of heating section 11 can be adjusted. The cooking device 10 is a gas stove, an IH stove, or the like.

[0021] The range hood 20 is equipped with a hood body 21, a blower 22, an operation switch 23, a control unit 24, a temperature sensor 25, a receiving unit 26, etc., and by driving the blower 22, oily smoke generated by cooking is collected in the hood body 21 and discharged outdoors. By manually operating the operation switch 23 and sending an operation signal or a stop signal to the control unit 24, the control unit 24 drives and stops the blower 22 to start and stop the range hood, and by sending an airflow volume control signal from the operation switch 23 to the control unit 24, the rotation speed of the blower 22 is changed to control the airflow volume, so that the range hood 20 can be manually operated. The heating signal and stop signal transmitted by the transmitting unit 14 of the cooking appliance 10 are received by the receiving unit 26 and sent to the control unit 24, which then drives and stops the blower 22 and starts and stops the operation of the range hood 20, so that the range hood 20 can be operated in conjunction with the cooking appliance 10.

[0022] The temperature sensor 25 constantly detects the temperature above the cooking appliance 10, and the detected temperature is sent to the control unit 24. The control unit 24 performs automatic operation control, which will be described later, based on the detected temperature, and automatically starts and stops the operation of the range hood 20. In other words, the control unit 24 has an automatic operation mode. Temperature sensor 25 is a compound temperature sensor that detects the temperature of each of the squares (pixels) into which the entire top surface of cooking device 10 is divided, and the maximum temperature of the square with the highest temperature is taken as the detected temperature. Alternatively, the average temperature of each square is taken as the temperature of that square, and the maximum temperature among the average temperatures is taken as the detected temperature. The temperature sensor 25 may be a monocular temperature sensor, and the maximum temperature or average temperature may be used as the detected temperature. The temperature sensor 25 may be, for example, an infrared sensor or an infrared camera. The temperature sensor 25 may be provided in a location other than the hood body 21 .

[0023] Next, an example of the automatic operation mode of the range hood 20 will be described. The temperature above the cooking device 10 heats the heating unit 11, causing the detected temperature of the temperature sensor 25 to change as shown in Fig. 2. In other words, the temperature gradually rises from the point when the heating unit 11 of the cooking device 10 is heated, becomes higher than the room temperature, and gradually drops from the point when the heating unit 11 is stopped, until it becomes lower than the room temperature. The control unit 24 sets a first predetermined temperature T1 higher than the room temperature, a second predetermined temperature T2 higher than the first predetermined temperature T1, a third predetermined temperature T3 higher than the second predetermined temperature T2, and a temperature gradient, that is, a first threshold value α1, a second threshold value α2, and a third threshold value α3 of the temperature rise gradient α of the temperature detected by the temperature sensor 25 in this embodiment.

[0024] The first predetermined temperature T1 is a reference temperature at which the blower 22 starts to operate, and the second predetermined temperature T2 is a reference temperature at which the blower 22 stops to operate. The third predetermined temperature T3 is a reference temperature at which a rapid temperature rise is judged. In the embodiment, it is preferable to set the first predetermined temperature T1 higher than the temperature detected by the sensor 25 of a human hand, and in the embodiment, in both cases where the cooking appliance 10 is a gas stove or an IH stove, the temperature detected by the temperature sensor 25 of a human hand is set to 30°C, and the average value over two seconds is set to 35°C. The second predetermined temperature T2 is set to 50° C. when the cooking appliance 10 is a gas stove, and to 40° C. when the cooking appliance 10 is an IH stove. The third set temperature T3 is set to 80°C.

[0025] In other words, since an IH stove does not use fire, the temperature during cooking does not rise as easily as with a gas stove, which uses fire, so the second predetermined temperature T2 is set higher for a gas stove than for an IH stove. The temperature rise gradient α is the amount of temperature change per certain time, and the first threshold α1 is the temperature rise gradient that is the control standard, and the amount of temperature change that is the control standard. The certain time can be changed according to the threshold used for judgment to make a more accurate judgment. The first threshold α1 is used to judge whether normal cooking is being performed, and is a value that indicates a temperature rise state in which the detected temperature rises during a certain time. It is preferable to set it to the minimum temperature change (greater than 0) that occurs when the cooking device 10 is used. However, if it is too low, it becomes easy to react to minute temperature changes due to reasons other than heating. Therefore, in the embodiment, the first threshold α1 is set as a rise of 0.1°C or more in the average temperature for 30 seconds from the average temperature for the 30 seconds 10 seconds prior. The second threshold value α2 is used to determine whether normal cooking is being performed, and is therefore a value indicating the temperature rise state. It is preferable to set it to the minimum amount of temperature change that occurs when the cooking device 10 is in use. On the other hand, by setting a condition higher than the first threshold value α1, the accuracy of determining whether heating has occurred can be improved. Therefore, in the embodiment, the second threshold value α2 is set as a rise of 0.5°C or more between the average temperature over a 3-second period and the average temperature over the 3-second period one second prior. The third threshold value α3 is used to determine a sudden temperature rise, and is a value indicating a temperature rise state, and is preferably greater than the amount of temperature change that occurs during normal use of the cooking device 10. Also, since it is preferable that the threshold value be one that results in a higher temperature rise than the second threshold value, the third threshold value α3 is set as a rise of 1°C or more between the average temperature over a 3-second period and the average temperature over the 3-second period one second prior.

[0026] The operation of the control unit 24 to automatically start driving the blower 22 will be described. The control unit 24 constantly calculates the temperature rise gradient α of the temperature detected by the temperature sensor 25 . In the embodiment, the temperature rise gradient α of the temperature detected by the temperature sensor 25 is repeatedly calculated from the average value of the temperature detected during a certain period of time and the average value of the temperature detected during a certain period of time from the certain period of time before that certain period of time. The control unit 24 determines whether the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the set first threshold value α1, and when it determines that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the set first threshold value α1, it determines whether the temperature detected by the temperature sensor 25 is equal to or greater than the set first predetermined temperature T1, and after determining that the temperature detected by the temperature sensor 25 is equal to or greater than the set first predetermined temperature T1, automatically starts operating the blower 22 when the temperature rise gradient α of the temperature detected by the temperature sensor 24 satisfies a predetermined condition.

[0027] In addition, it is also possible to determine whether the temperature detected by temperature sensor 25 is equal to or higher than a set first predetermined temperature T1, and when it is determined that the temperature detected by temperature sensor 25 is equal to or higher than the first predetermined temperature T1, determine whether the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or higher than a set first threshold value α1, and after determining that the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or higher than the set first threshold value α1, and then automatically start operating blower 22 if the temperature rise gradient α of the temperature detected by temperature sensor 24 satisfies a predetermined condition. That is, after satisfying that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the set first threshold value α1 and that the temperature detected by the temperature sensor 24 is equal to or greater than the first predetermined temperature T1, the control unit 24 automatically starts operating the blower 22 when the temperature rise gradient α of the temperature detected by the temperature sensor 24 satisfies a predetermined condition. The determination of whether the temperature detected by the temperature sensor 25 is equal to or higher than the first predetermined temperature T1 may be made based on the detected temperature at the time of determination, or may be made based on the average value of the temperature detected by the temperature sensor 25, or whether the temperature is higher (lower) than the first predetermined temperature T1 for a predetermined period of time.

[0028] According to the automatic operation mode of the present invention, when cooking is performed with the cooking appliance 10 in the heating state, the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the first threshold value α1, the temperature detected by the temperature sensor 25 is equal to or greater than the first predetermined temperature T1, and the temperature on the cooking appliance 10 rises due to heating thereafter, so the temperature rise gradient α of the temperature detected by the temperature sensor 25 satisfies the predetermined condition, and therefore, when the cooking appliance 10 is in the heating state, the blower 22 can be automatically started to be driven. The heating state of the cooking appliance 10 is a state in which the cooking appliance 10 is ignited and a flame is generated if the cooking appliance 10 is a gas stove, and is a state in which the cooking appliance 10 is energized and heat is generated if the cooking appliance 10 is an IH stove. Even if it is satisfied that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the set first threshold value α1 and that the temperature detected by the temperature sensor 25 is equal to or greater than the first predetermined temperature T1, if the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not subsequently satisfy the predetermined condition, the blower 22 will not automatically start operating, thereby preventing the blower 22 from automatically starting operating due to a false detection when the cooking appliance 10 is not in a heating state.

[0029] For example, when a cooked food item is moved onto heating adjuster 10 that is not in a heated state, the temperature on cooking appliance 10 rises immediately after the move, and it may be determined that it is satisfied that the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the set first threshold value α1 and that the temperature detected by temperature sensor 25 is equal to or greater than the first predetermined temperature T1. However, since cooking appliance 10 is not in a heated state and no heating is being performed, a continuous temperature rise does not occur, and the temperature on cooking appliance 10 does not rise thereafter. As a result, the temperature rise gradient α of the temperature detected by temperature sensor 25 does not satisfy the predetermined condition, and blower 22 does not automatically start operating. Therefore, it is possible to prevent blower 22 from automatically starting operating due to a false detection when cooking appliance 10 is not in a heated state.

[0030] Next, the predetermined condition for the temperature rise gradient α of the temperature detected by the temperature sensor 25 will be described. When cooking with the cooking appliance 10 in a heated state, the temperature rise gradient α of the temperature detected by the temperature sensor 25 becomes equal to or greater than the set first threshold value α1 and the temperature detected by the temperature sensor 25 becomes equal to or greater than the set first predetermined temperature T1. Therefore, by determining that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the set first threshold value α1 and the temperature detected by the temperature sensor 25 is equal to or greater than the set first predetermined temperature T1, the blower 22 may be automatically started to operate. However, when the cooking appliance 10 is not in a heated state, the temperature rise gradient α of the temperature detected by the temperature sensor 25 may become equal to or greater than the set first threshold value α1 and the temperature detected by the temperature sensor 25 may become equal to or greater than the set first predetermined temperature T1, in which case the blower 22 will be started to operate unnecessarily.

[0031] For example, when a heated food item, such as a heated pot, is moved onto a cooking appliance 10 that is not in a heated state, the detected temperature of the temperature sensor 25 changes as shown in FIG. 3, and the temperature rise gradient α of the detected temperature may become equal to or greater than the first threshold value α1, and the detected temperature may become equal to or greater than the first predetermined temperature T1. In such a case, the blower 22 will automatically start operating. Therefore, in the present invention, after the temperature rise gradient α is equal to or greater than a set first threshold value α1 and the detected temperature detected by temperature sensor 25 is equal to or greater than a set first predetermined temperature T1, if the temperature rise gradient α of the temperature detected by temperature sensor 25 satisfies a predetermined condition, the blower 22 is not automatically started to operate if the predetermined condition is not satisfied, thereby preventing the blower 22 from being unnecessarily started to operate due to a false detection when the cooking appliance 10 is not in a heating state.

[0032] A first embodiment of the predetermined condition will be described. This embodiment is intended to prevent the blower 22 from automatically starting to operate due to a false detection caused by a temperature rise when the cooking appliance 10 is not in a heating state. For example, when a heated food item is moved onto the cooking device 10, as shown in FIG. 3, the temperature detected by the temperature sensor 25 rises to or above the first predetermined temperature T1 immediately after the move, and the temperature rise gradient α of the temperature detected by the temperature sensor 25 becomes equal to or above the first threshold value α1. However, since the cooking device 10 is not in a heating state, a continuous temperature rise does not occur, and the temperature gradually decreases over time.

[0033] When the cooking appliance 10 is in a heating state and cooking is being performed, as shown in FIG. 2, even after the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the first threshold value α1 and the temperature detected by the temperature sensor 25 is equal to or greater than the first predetermined temperature T1, the temperature detected by the temperature sensor 25 continues to rise due to heating, and the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2.

[0034] With this in mind, after it is determined that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the first threshold value α1 and the temperature detected by the temperature sensor 25 is equal to or greater than the first predetermined temperature T1, it is determined that the temperature rise gradient α of the temperature detected by the temperature sensor 25 satisfies the predetermined condition when the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2. In other words, the predetermined condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2.

[0035] With this configuration, when the cooking device 10 is in a heating state and cooking is being performed, the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2, satisfying the specified condition, so that the blower 22 can automatically start operating. In addition, if a heated food item is moved onto the cooking device 10 when the cooking device 10 is not in a heated state, the food item is not heated and therefore a continuous temperature rise does not occur, and the temperature rise gradient α of the temperature detected by the temperature sensor 25 is less than the second threshold value α2, which does not satisfy the specified condition, so that the blower 22 does not automatically start operating, thereby preventing the blower from automatically starting operating due to a false detection when the cooking device 10 is not in a heated state.

[0036] A second embodiment of the predetermined condition will now be described. Like the first embodiment, this embodiment prevents the fan from automatically starting to operate due to erroneous detection caused by a temperature rise when the cooking appliance is not in a heating state. When the predetermined condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value, the blower 22 may automatically start to operate due to an erroneous detection. For example, if a heated food item is moved onto the cooking device 10 when the cooking device 10 is not in a heating state, and then the food item is stirred or the lid of the food item is removed, the temperature on the cooking device 10 may rise even though heating is not being performed, and the temperature rise gradient α of the temperature detected by the temperature sensor 25 may temporarily become equal to or greater than the second threshold value α2, satisfying the specified condition and causing the blower 22 to automatically start operating.

[0037] In order to solve this problem, the predetermined condition is set so that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2 for a set predetermined time period. According to this configuration, the blower 22 automatically starts operating when the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2 for a predetermined time. Therefore, when the cooking appliance 10 is not in a heating state and heating is not being performed, the temperature does not rise continuously, and the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2 for a shorter period of time than the predetermined period of time. Therefore, when the cooking appliance 10 is not in a heating state, the blower 22 can be prevented from automatically starting operating due to erroneous detection. In other words, the longer the predetermined time, the more it can prevent automatic start of blower 22 due to erroneous detection. On the other hand, if the predetermined time is long, it takes time until automatic start of blower 22. Taking both circumstances into consideration, the predetermined time is set to 10 seconds in this embodiment.

[0038] For example, if a cooked food is moved onto the cooker 10 without heating the cooker 10, and the food is stirred or the lid is removed, the temperature on the cooker 10 may rise even if heating is not being performed. Even in such a case, the temperature rises when the food is stirred or the lid is removed, but the temperature does not rise thereafter and a continuous temperature rise does not occur, so that the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not continue to be equal to or greater than the second threshold value α2 for a predetermined period of time, and therefore it is possible to prevent the blower 22 from automatically starting to operate due to erroneous detection. The temperature may be detected continuously for a predetermined period of time, or may be detected at regular intervals.

[0039] A third embodiment of the predetermined condition will now be described. Like the first and second embodiments, this embodiment prevents the fan from automatically starting to operate due to erroneous detection caused by a temperature rise when the cooking appliance is not in a heated state. When the predetermined condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value, the blower 22 may automatically start to be driven due to an erroneous detection. For example, if a heated food item is moved onto the cooking device 10 when the cooking device 10 is not in a heating state, and then the food item is stirred or the lid of the food item is removed, the temperature on the cooking device 10 may rise even though heating is not being performed, and the temperature rise gradient α of the temperature detected by the temperature sensor 25 may temporarily become equal to or greater than the second threshold value α2, satisfying the specified condition and causing the blower 22 to automatically start operating. In order to solve this problem, the predetermined condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the set second threshold value α2 for a predetermined number of consecutive times. According to this configuration, when the temperature rise gradient α of the detected temperature of temperature sensor 25 becomes equal to or greater than the set second threshold value α2 for a predetermined number of consecutive times or more, blower 22 automatically starts operating, and when the temperature does not become equal to or greater than the second threshold value α2 for a predetermined number of consecutive times or more, blower 22 does not automatically start operating. Therefore, it is possible to prevent automatic start of blower 22 due to erroneous detection caused by a temperature rise when cooking appliance 10 is not in a heating state and heating is not being performed.

[0040] For example, when a cooked food is moved onto the cooker 10 without the cooker 10 being in a heated state, the temperature on the cooker 10 may rise if the cooked food is stirred or the lid is removed even if heating is not being performed by the cooker 10. Even in such a case, the temperature rises when the food is stirred or the lid is removed, but the temperature does not rise thereafter and a continuous temperature rise does not occur, so that the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not continue to be equal to or greater than the second threshold value α2 for a predetermined number of times or more, and the blower 22 does not automatically start operating because the predetermined condition is not satisfied. Therefore, when the cooking appliance 10 is not in a heating state and no heating is being performed, it is possible to prevent the blower 22 from being automatically started to be driven due to an erroneous detection caused by a temperature rise.

[0041] A fourth embodiment of the predetermined condition will now be described. As shown in Fig. 4, when the cooking appliance 10 is in the heating state, the temperature detected by the temperature sensor 25 may change due to some factor, for example, the cooking appliance 10 being heated at low heat, causing the temperature rise to be unstable, and the temperature may drop for a short period of time as shown in Fig. 4(a) during the temperature rise after the cooking appliance is in the heating state, and then rise again. In this case, the temperature rise gradient α of the temperature detected by the temperature sensor 25 falls below the second threshold α2, and the blower 22 may not be able to start driving automatically. To solve this problem, in this embodiment, the predetermined condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not fall below the set second threshold value α2 continuously during a set predetermined time. In this embodiment, the predetermined time is set to 10 seconds.

[0042] According to this configuration, when cooking with the cooking appliance 10 in the heating state, even if the temperature drops during the temperature rise after the heating state is set due to some factor, the temperature rises again, so that if the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not fall continuously below the set second threshold value α2 during a set predetermined time, the blower 22 can be automatically started to be driven, and it is possible to prevent the blower 22 from being unable to be started to be driven due to a temporary temperature drop. Therefore, the heating state can be determined quickly. When the cooking device 10 is not in a heated state, the temperature rise gradient α of the temperature detected by the temperature sensor 25 falls continuously below the set second threshold value α2 during a set specified time, so that the blower 22 does not automatically start operating, and automatic start of operation of the blower 22 due to erroneous detection when the cooking device 10 is not in a heated state can be prevented.

[0043] A fifth embodiment of the predetermined condition will now be described. In this embodiment, like the fourth embodiment, when cooking with the cooking appliance 10 in the heated state, even if the temperature drops during the temperature rise after the cooking appliance 10 is placed in the heated state due to some factor, the blower 22 is automatically started to operate, preventing a situation in which the blower 22 cannot be started automatically due to a temporary drop in temperature, and also preventing the blower 22 from automatically starting to operate due to a false detection when the cooking appliance 10 is not in the heated state. The specified condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not fall below the set second threshold value α2 consecutively, and that the temperature rise gradient α of the temperature detected by the temperature sensor 25 becomes equal to or greater than the set second threshold value α2 a specified number of times or more.

[0044] According to this configuration, when cooking with the cooking appliance 10 in the heating state, even if the temperature drops during the temperature rise after the heating state is set due to some factor, the blower 22 can be automatically started to be driven unless the temperature rise gradient α of the temperature detected by the temperature sensor 25 falls continuously below the set second threshold value α2 within a set predetermined time, and it is possible to prevent the blower 22 from being unable to be automatically started to be driven due to a temporary temperature drop. Therefore, the heating state can be quickly determined. When the cooking device 10 is not in a heated state, the temperature rise gradient α of the detected temperature of the temperature sensor 25 falls below the second threshold value α2 consecutively before reaching or exceeding the second threshold value α2 set a predetermined number of times or more, so that the blower 22 does not automatically start operating. This prevents the blower 22 from automatically starting operating due to erroneous detection when the cooking device 10 is not in a heated state.

[0045] For example, when the cooking device 10 is not in a heating state and is not heating, if a heated food is moved onto the cooking device 10 and the food is stirred or the lid of the food is removed even when the cooking device 10 is not heating, the temperature on the cooking device 10 may rise. Even in such a case, the temperature rises when the food is stirred or the lid is removed, but the temperature does not rise thereafter. Therefore, the temperature rise gradient α of the detected temperature of the temperature sensor 25 falls below the second threshold α2 consecutively before reaching or exceeding the second threshold α2 set a predetermined number of times or more, and the blower 22 does not automatically start to operate. Therefore, it is possible to prevent the blower 22 from automatically starting to operate due to erroneous detection when the cooking device 10 is not in a heating state. Therefore, when cooking with cooking appliance 10 in the heated state, even if the temperature drops during the temperature rise after the cooking appliance is placed in the heated state due to some factor, blower 22 can be automatically started to be driven, preventing blower 22 from being unable to be automatically started to be driven due to a temporary drop in temperature and preventing blower 22 from automatically starting to be driven due to erroneous detection when cooking appliance 10 is not in the heated state.

[0046] Next, a first embodiment of the operation of automatically starting driving the blower 22 when the cooking appliance 10 is placed in a heating state without a cooking appliance such as a pan being placed on it will be described. When the cooking device 10 is heated without placing a cooking device such as a pot on it, it may be difficult for the temperature sensor 25 to stably detect the temperature. For example, when the cooking device 10 is a gas stove, the temperature sensor 25 directly detects the temperature of the flame. In other words, it detects the temperature of an open flame. The temperature detected by the temperature sensor 25 that directly detects the flame changes as shown in Fig. 5. That is, by being in a heated state, the temperature exceeds the first predetermined temperature T1 and rises to a third predetermined temperature T3 or higher, and thereafter the temperature gradually increases while repeating rapid temperature increases and decreases due to the fluctuation of the flame, etc. Therefore, the temperature rise gradient α of the temperature detected by the temperature sensor 25 immediately after the heating state is set is equal to or greater than the first threshold value α1, and the detected temperature is equal to or greater than the first predetermined temperature T1.

[0047] However, it is difficult to stably detect the temperature of the flame, which is generated by repeated rapid temperature increases and decreases, and it is difficult to determine whether the specified conditions described above are met. As a result, it is not possible to obtain a result indicating that the temperature rise gradient α of the temperature detected by temperature sensor 25 satisfies the specified conditions described above, and it may not be possible to automatically start operating blower 22. When the cooking device 10 is heated without placing a cooking device such as a pot on it, no oily smoke or the like is generated due to cooking. However, since the cooking device is heated, carbon dioxide and carbon monoxide are generated, and carbon monoxide poisoning may occur if ventilation is not performed. Therefore, it is desirable to operate the blower 22 to ventilate the room.

[0048] Therefore, if a sudden temperature rise is detected a predetermined number of times while determining whether a predetermined condition is met, the blower 22 is automatically started regardless of the predetermined condition, thereby preventing carbon monoxide poisoning, etc. Specifically, the third threshold value α3 is set to a value higher than the temperature rise gradient α during normal cooking, and the blower 22 is configured to automatically start operating when the temperature rise gradient α of the temperature detected by the temperature sensor 25 exceeds the third threshold value α3 a predetermined number of times during the determination of the specified conditions. According to this configuration, even if the temperature detected by temperature sensor 25 repeatedly rises and falls suddenly and the temperature cannot be detected stably and the specified conditions cannot be met, the blower 22 can be automatically started to be driven.

[0049] Next, a second embodiment of the operation of automatically starting driving blower 22 when cooking appliance 10 is placed in a heating state without a cooking appliance such as a pan being placed on it will be described. As mentioned above, if a heated food item is moved onto the cooking device 10 without the cooking device 10 being in a heated state, and the food item is stirred or the lid of the food item is removed, the temperature on the cooking device 10 may suddenly rise or fall even when no heating is being performed. For this reason, in the configuration of the first embodiment, when the food is stirred or the lid is removed from the food several times, a false detection may occur and blower 22 may automatically start to be driven.

[0050] After various investigations to resolve this issue, it was found that when the cooking appliance 10 is heated without placing a cooking appliance such as a pot on it, the temperature of the flame is higher than the third set temperature T3 as shown in FIG. 5, because the cooking appliance 10 is heated, and the temperature gradually increases while repeating rapid temperature increases and decreases, and the temperature before the rapid temperature increase gradually increases with each rapid temperature increase. That is, as shown in FIG. 5, the temperature Tn before a sudden temperature rise is higher than the temperature Tn-1 before the previous sudden temperature rise.

[0051] Taking note of this, when the temperature rise gradient α of the temperature detected by the temperature sensor 25 exceeds the third threshold value α3, the temperature Tn-1 before the temperature rise is stored, and when the temperature rise gradient α of the temperature detected by the temperature sensor 25 next exceeds the third threshold value α3, the temperature Tn before the temperature rise is stored. This process is repeated until the temperature Tn before the temperature rise stored this time exceeds the temperature Tn-1 before the temperature rise stored previously or the temperature detected by the temperature sensor 25 remains higher than the third predetermined temperature T3, and the blower 22 is automatically started to operate when the temperature Tn before the temperature rise stored this time exceeds the temperature Tn-1 before the temperature rise stored previously a predetermined number of times.

[0052] In other words, the temperature sensor is configured to detect not the number of times the temperature suddenly rises, but the gradual increase in temperature before the sudden temperature rise. With this configuration, even if the temperature on the cooking device 10 detected by the temperature sensor 25 repeatedly rises and falls suddenly and the temperature cannot be detected stably and the specified conditions cannot be met, the blower 22 can be automatically started to operate. Furthermore, when a cooked food is moved onto cooking device 10 without cooking device 10 being in a heated state, if the temperature on cooking device 10 rises or falls suddenly by stirring the food or removing the lid from the food, the temperature detected by temperature sensor 25 will gradually fall, and the temperature before the current sudden temperature rise will be lower than the temperature before the previous sudden temperature rise, so that blower 22 will not automatically start operating, and automatic start of blower 22 due to erroneous detection when cooking device 10 is not in a heated state can be prevented. It is preferable that the third set temperature T3 is set to a temperature lower than the temperature of the heating unit 11 in the weak heating state detected directly by the temperature sensor 25. Also, by setting the third set temperature T3 to a value as high as possible within that range, it is possible to increase the accuracy of distinguishing between a sudden temperature rise caused by cooking with heat and a sudden temperature rise caused by directly detecting the heating unit 11 in the heated state. Also, depending on the timing of the measurement, the temperature before the sudden temperature rise may not be the lowest temperature when the sudden temperature rise occurred. For example, the temperature measured just before the actual sudden temperature rise or during the temperature rise may be the temperature before the sudden temperature rise in the measurement. In such a case, even if a flame is directly detected, the temperature Tn before the temperature rise measured and stored this time may be lower than the temperature Tn-1 before the temperature rise stored last time. However, if a flame is detected, the temperature exceeds the third set temperature T3, so the counter is not reset, and the blower 22 can be automatically started to be driven while the measurement is repeated.

[0053] A specific operation when the predetermined condition is that of the first embodiment will be described with reference to the flow chart shown in FIG. That is, first, starting from a standby mode state in which blower 22 is stopped, it is determined whether the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than a first threshold value α1 (S100). If it is determined that the temperature detected by temperature sensor 25 is equal to or greater than the first threshold value α1 (S100, YES), it is determined whether the temperature detected by temperature sensor 25 is equal to or greater than a first predetermined temperature T1 (S101). If it is equal to or greater than the first predetermined temperature T1 (S101, YES), a counter provided in control unit 24 that counts time t1 for measuring a predetermined time (60 seconds in this case) for determining whether a predetermined condition is satisfied is set to t1 = zero and starts counting (S102).

[0054] It is determined whether t1 is less than 60 seconds (S103), and if it is less than 60 seconds (S103, YES), it is determined that it is within a predetermined time period, and it is determined whether the temperature rise gradient α is greater than or equal to the second threshold value α2 (S104), and if it is greater than or equal to the second threshold value α2 (S104, YES), it is determined that the temperature rise gradient α is greater than or equal to the second threshold value α2, and the blower 22 is automatically started to operate (S105). If t1 is 60 seconds or more (S103, NO), it is determined that a predetermined time has elapsed, and the counter that counts t1 stops counting t1, resets the count of t1 (S106), and returns to the beginning. Also, it is determined whether the temperature rise gradient α is equal to or greater than a first threshold value α1 (S100), and if it is determined that it is not equal to or greater than the first threshold value α1 (S100, NO), it is determined whether the temperature detected by the temperature sensor 25 is equal to or greater than a first predetermined temperature T1 (S101), and if it is determined that it is not equal to or greater than the first predetermined temperature T1 (S101, NO), it also returns to the beginning. As a result, if the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the first threshold value α1, and within a specified time after it is determined that the temperature detected by temperature sensor 25 is equal to or greater than the first predetermined temperature T1, the blower 22 automatically starts operating, and if the temperature rise gradient α does not become equal to or greater than the second threshold value α2 within the specified time, the blower 22 does not automatically start operating.

[0055] The specific operation when the specified condition is the second embodiment, in which the operation of automatically starting the operation of blower 22 when a cooking device such as a pot is not placed on cooking device 10 and the cooking device is in a heating state, is the second embodiment, will be described with reference to the flowchart shown in FIG. That is, the process starts from a standby mode state in which the blower 22 is stopped, and N=0 is set (S200). N is the number of times that the temperature Tn before the sudden temperature rise due to the temperature rise gradient α of the temperature detected by the temperature sensor 25 exceeding the third threshold value α3 is higher than the temperature Tn-1 before the previous sudden temperature rise. First, similarly to S100 to S103 of the flowchart described in FIG. 6, it is determined whether the temperature rise gradient α of the temperature detected by the temperature sensor 25 is greater than or equal to the first threshold value α1 (S201). If it is greater than or equal to the first threshold value α1 (S201, YES), it is determined whether the temperature detected by the temperature sensor 25 is greater than or equal to a first predetermined temperature T1 (S202). If it is greater than or equal to the first predetermined temperature T1 (S202, YES), a counter that counts time t1 is set to t1=zero and counting is started (S203).

[0056] Then, a counter that counts a time t2 for counting a predetermined time is set to t2=0 and the count is started (S204). It is determined whether t1 is less than 60 seconds (S205), and if it is less than 60 seconds (S205, YES), it is determined that it is within a predetermined time period, and it is determined whether the temperature rise gradient α is equal to or less than a third threshold value α3 (S206). If t1 is 60 seconds or more (S205, NO), it is determined that a predetermined time has elapsed, and the counter that counts t1 stops counting t1 and t2, resets the counts of t1 and t2 (S207), and returns to the beginning. Also, it is determined whether the temperature rise gradient α is equal to or greater than the first threshold value α1 (S201), and if it is determined that it is not equal to or greater than the first threshold value α1 (S201, NO), it is determined whether the temperature detected by the temperature sensor 25 is equal to or greater than the first predetermined temperature T1 (S202), and if it is determined that it is not equal to or greater than the first predetermined temperature T1 (S202, NO), it also returns to the beginning.

[0057] If the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or less than the third threshold value α3 (S206, YES), it is determined that there is no sudden temperature rise, and it is determined whether the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the second threshold value α2 (S208). If the temperature rise gradient α is equal to or greater than the second threshold value α2 (S208, YES), it is determined whether the time (counted t2) during which the temperature rise gradient α is equal to or greater than the second threshold value α2 is equal to or greater than a predetermined time (S209). If it is equal to or greater than the predetermined time (S209, YES), it is determined that the temperature rise gradient α has been equal to or greater than the second threshold value α2 for the predetermined time, and the blower 22 is automatically started to operate (S210). If it is less than the predetermined time (S209, NO), the process returns to S205 and does not automatically start driving the fan 22. If the temperature rise gradient α is not equal to or greater than the second threshold value α2 (S208, NO), the counter that counts t2 is reset again and starts counting from t2=0 (S204).

[0058] If the temperature rise gradient α of the temperature detected by the temperature sensor 25 exceeds the third threshold α3 (S206, NO), it is determined that there is a sudden temperature rise, and the temperature Tn before the sudden temperature rise is stored. Then, it is determined whether the stored temperature Tn before the sudden temperature rise exceeds the temperature Tn-1 before the previous sudden temperature rise (S211). When it is determined that Tn exceeds Tn-1 (S211, YES), the counter that counts N is counted to 1 (S212), and the number of times that the temperature rise gradient α of the temperature detected by the temperature sensor 25 exceeds the third threshold value α3 is counted. It is determined whether the counted number N is equal to or greater than a predetermined number (4 in this case) (S213), and if it exceeds the predetermined number (S213, YES), the blower 22 is automatically started to operate (S210), and if it is less than the predetermined number (S213, NO), the temperature detected by the temperature sensor 25 is compared with the first predetermined temperature T1 (S202).

[0059] If Tn is equal to or less than Tn-1 (S211, NO), it is determined whether Tn is equal to or less than a third predetermined temperature T3 (S214), and if Tn is equal to or less than the third predetermined temperature T3 (S214, YES), the counter that counts N is reset to N=0 (S215), and the counter that counts t2 is reset again to start counting from t2=0 (S204), and if Tn exceeds the third predetermined temperature T3 (S214, NO), it is determined whether t1 is equal to or more than a predetermined time (S205).

[0060] This operation counts the number of times that the currently stored temperature (Tn) exceeds the previously stored temperature (Tn-1) or exceeds the third predetermined temperature T3 and Tn exceeds Tn-1. In other words, the blower 22 automatically starts to operate when the currently stored temperature (Tn) exceeds the previously stored temperature (Tn-1) a predetermined number of times while the temperature is rising or, since Tn is the temperature detected by the temperature sensor 25, the temperature detected by the temperature sensor 25 (Tn) is higher than the third predetermined temperature T3 and a flame is continuously detected. Moreover, since the determination as to whether the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or less than the third threshold value α3 (S206) is performed before the determination as to whether the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2 (S208), the above operations are performed during the determination of the specified conditions.

[0061] In the flowchart of Fig. 7, S211 and S214 may not be provided, and NO in S206 may be directly connected to S212. This is the first embodiment for preventing the automatic start of driving the blower due to erroneous detection when the cooking appliance 10 is not in the heating state. That is, when the temperature rise gradient α of the temperature detected by the temperature sensor 25 exceeds the third threshold value α3 a predetermined number of times during the determination of the predetermined condition, the blower 22 is configured to automatically start operating.

[0062] The specific operation when the specified condition is the third embodiment and the operation of automatically starting the operation of the blower 22 when the cooking appliance 10 is in a heating state without placing a cooking appliance such as a pot on the cooking appliance 10 is the second embodiment, will be described based on the flowchart shown in FIG. 8. That is, first, in the flowchart shown in FIG. 8, S301 to S305 are the same as S100 to S103 and S106 in the flowchart already explained in FIG. 6, and it is determined whether a predetermined time has elapsed since it was determined that the detected temperature α of the temperature sensor 25 is equal to or greater than the first threshold value α1 and that the detected temperature of the temperature sensor 25 is equal to or greater than the first predetermined temperature T1.

[0063] In the flowchart shown in FIG. 8, S306 to S311 are the same as S206, S211 to S215 in the flowchart already described in FIG. 7, and after it is determined that the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the first threshold value α1 and that the temperature detected by temperature sensor 25 is equal to or greater than the first predetermined temperature T1, the number of times that the temperature rise gradient α of the temperature detected by temperature sensor 25 exceeds the third threshold value α3 during the determination of the predetermined conditions and the temperature Tn before the sudden temperature rise is higher than the temperature Tn-1 before the previous sudden temperature rise is counted, and the blower 22 is automatically started to be driven.

[0064] Here, the process starts from a standby mode state in which the blower 22 is stopped, and initially, K=0 and N=0 are set (S300). K is the number of times that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2. Then, it is determined whether the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or less than the set third threshold value α3 (S306), and if it is determined that the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or less than the third threshold value α3 (S306, YES), the temperature rise gradient α of the temperature detected by temperature sensor 25 is compared with the second threshold value α2 (S312), and if it is determined that the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the second threshold value α2 (S312, YES), 1 is counted into a counter that counts K (S313), and it is determined whether K is equal to or greater than a predetermined number of times (here, 10) (S314).

[0065] If the temperature rise gradient α of the temperature detected by the temperature sensor 25 exceeds the third threshold value α3, the temperature rise gradient α is equal to or greater than the second threshold value α2. Therefore, if it is determined that the temperature rise gradient α exceeds the third threshold value α3 (S306, NO), a counter that counts K is used to count K+1 (S315). This makes it possible to accurately count the number of times that the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or greater than the second threshold value α2.

[0066] If the temperature rise gradient α of the temperature detected by the temperature sensor 25 falls below the second threshold α2 (S312, NO), the counter that counts K is reset to K=0 (S316), and it is determined whether t1 is equal to or longer than a predetermined time (S304). As a result, when the temperature rise gradient α of the temperature detected by temperature sensor 25 exceeds second threshold value α2 a predetermined number of times (here, 10 times) or more in succession (S314, YES), driving of blower 22 is automatically started (S317). When the temperature rise gradient α of the temperature detected by temperature sensor 25 does not exceed second threshold value α2 a predetermined number of times or more in succession (S314, NO), it is again determined whether t1 is equal to or longer than the predetermined time (S304).

[0067] The specific operation when the specified conditions are the fourth and fifth embodiments and the operation of automatically starting the operation of the blower 22 when the cooking appliance 10 is in a heating state without placing a cooking appliance such as a pot on the cooking appliance 10 is the second embodiment, will be described based on the flowchart shown in FIG. 9. That is, first, in the flowchart shown in FIG. 9, S401 to S406 are the same as S201 to S205 and S207 in the flowchart already explained in FIG. 7, and it is determined whether a predetermined time has elapsed since it was determined that the detected temperature α of the temperature sensor 25 is equal to or greater than the first threshold value α1 and that the detected temperature of the temperature sensor 25 is equal to or greater than the first predetermined temperature T1.

[0068] In the flowchart shown in FIG. 9, S407 to S413 are the same as S306, S315, and S307 to S311 already described in the flowchart shown in FIG. 8, and after the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the first threshold value α1 and the temperature detected by temperature sensor 25 is equal to or greater than the first specified temperature T1, the number of times that the temperature rise gradient α of the temperature detected by temperature sensor 25 exceeds the third threshold value α3 during determination of the specified conditions and the temperature Tn before the sudden temperature rise is higher than the temperature Tn-1 before the previous sudden temperature rise is counted, and the blower 22 is automatically started to be driven.

[0069] Here, the process starts from a standby mode state in which the blower 22 is stopped, and initially, K=0 and N=0 (S400). Then, if it is determined that the temperature detected by the temperature sensor 25 is equal to or higher than the first predetermined temperature T1 (S402, YES), a counter provided in the control unit 24 for counting a time t1 is started from t1=0 (S403), a counter for counting a time t2 for measuring the predetermined time is started from t2=zero (S404), and it is determined whether t1 is less than the predetermined time (S405). If it is less than the predetermined time (S405, YES), the temperature rise gradient α of the temperature detected by the temperature sensor 25 is equal to or higher than the set third temperature T1. It is determined whether the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or less than threshold value α3 (S407), and if the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or less than the third threshold value α3 (S407, YES), it is determined whether the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the second threshold value α2 (S414), and if the temperature rise gradient α of the temperature detected by temperature sensor 25 is equal to or greater than the second threshold value α2 (S414, YES), the counter that counts K is counted to 1 (S415), and it is determined whether the counted time t2 is equal to or greater than a predetermined time (here, 10 seconds) (S416).

[0070] If t2 is equal to or longer than the predetermined time (S416, YES), the temperature rise gradient α has not been continuously below the second threshold value α2 for the predetermined time, and so the blower 22 is automatically started to be driven (S417). Therefore, the predetermined condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 has not been continuously below the second threshold value α2 for the predetermined time (here, t1=10 seconds). If t2 is less than a predetermined time (S416, NO), it is determined whether K is a predetermined number of times (here, 10 times) or more (S418), and if it is the predetermined number of times or more (S418, YES), the blower 22 is automatically started to be driven, and if it is less than the predetermined number of times (S418, NO), it is determined again whether t1 is greater than or equal to a predetermined time (S405). For this reason, the predetermined condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not fall below the second threshold value α2 consecutively and becomes equal to or greater than the second threshold value α2 a predetermined number of times or more.

[0071] When the temperature rise gradient α of the temperature detected by temperature sensor 25 falls below second threshold value α2 (S414, NO), it is determined whether the temperature rise gradient α of the temperature detected by temperature sensor 25 was also below second threshold value α2 last time (S419), and if it was (S419, YES), the counter that counts K is reset to K=0 (S420), the counter that counts t2 is reset to start counting from t2=0 (S404), and it is determined again whether t1 is equal to or longer than a predetermined time (S405). As a result, when the temperature rise gradient α of the temperature detected by temperature sensor 25 falls below second threshold value α2, if the temperature rise gradient α was also below second threshold value α2 last time, blower 22 does not automatically start driving.

[0072] If the temperature rise gradient α of the temperature detected by the temperature sensor 25 falls below the second threshold value α2 (S414, NO), and if the temperature rise gradient α of the temperature detected by the temperature sensor 25 was equal to or greater than the second threshold value α2 the previous time (S419, NO), it is determined whether t2 is equal to or greater than a predetermined time (S416), and if t2 is equal to or greater than the predetermined time (S416, YES), the blower 22 is automatically started to operate (S417). In this way, when the temperature rise gradient α of the temperature detected by temperature sensor 25 falls below the second threshold value α2 continuously (S419, YES), the counter becomes K=0, t2=0, and blower 22 does not automatically start operating before t2 reaches the specified time, but if it does not fall below the second threshold value α2 continuously within the specified time, blower 22 automatically starts operating.Therefore, the specified condition is that the temperature rise gradient α of the temperature detected by temperature sensor 25 does not fall below the second threshold value α2 continuously within the specified time.

[0073] If t2 is less than the predetermined time (S416, NO), it is determined whether K is equal to or greater than a predetermined number of times (here, 10 times) (S418), and if it is equal to or greater than the predetermined number of times (S418, YES), the blower 22 is automatically started to be driven (S417). If K is less than the predetermined number of times (S418, NO), it is again determined whether t1 is equal to or greater than the predetermined time (S405). Therefore, the specified condition is that the temperature rise gradient α of the temperature detected by the temperature sensor 25 does not fall below the second threshold value α2 consecutively, and the temperature rise gradient α of the temperature detected by the temperature sensor 25 becomes equal to or greater than the second threshold value α2 a specified number of times or more.

[0074] Next, a configuration for stopping the driving of the blower 22 that is being driven in the automatic operation mode will be described. The control unit 24 counts the time since the blower 22 is driven using a counter, and when the detected temperature of the temperature sensor 25 falls below the set second predetermined temperature T2 after the counted time has elapsed, the control unit 24 stops driving the blower 22. The set time is equal to or longer than the time required for the temperature to rise from the predetermined temperature T1 to the second predetermined temperature T2 at the first threshold value α1, and is 5 minutes in this embodiment. When the counted time is shorter than the set time, even if the temperature detected by the temperature sensor 25 falls below the second predetermined temperature T2, the blower 22 continues to be driven without being stopped.

[0075] In other words, after blower 22 has been in automatic operation (i.e., automatically started and continues to operate) for a set time or longer, when the temperature detected by temperature sensor 25 falls below second predetermined temperature T2, blower 22 is automatically stopped from operating, and when the automatic operation time of blower 22 is shorter than the set time, blower 22 continues to operate even if the temperature detected by temperature sensor 25 falls below second predetermined temperature T2. With this configuration, the blower 22 can be automatically operated continuously from the time when the cooking appliance 10 is put into a heating state until the time when the cooking appliance 10 is put into a heating stopped state. Furthermore, even if the temperature immediately after the start of driving of the blower 22 is low (below the second predetermined temperature T2), it is possible to prevent the driving of the blower 22 from being stopped due to erroneous detection.

[0076] For example, immediately after the automatic operation of the blower 22 starts, the temperature above the cooking appliance 20 may be low and the temperature detected by the temperature sensor 25 may be lower than the second predetermined temperature T2. If the operation of the blower 22 were to be automatically stopped when the temperature detected by the temperature sensor 25 simply fell below the second predetermined temperature T2, the blower would stop immediately after the automatic operation started, and the blower 22 would not be able to continue to operate automatically from the time the cooking appliance 10 is put into the heating state until it is put into the heating stop state. In addition, after the set time has elapsed, the detected temperature of the temperature sensor 25 becomes high due to the use of the cooking appliance 10, so the detected temperature of the temperature sensor 25 falls below the second predetermined temperature T2 after the set time has elapsed only after the heating of the cooking appliance 10 has stopped, and the operation of the blower 22 can be automatically stopped at the correct timing.

[0077] The above operation of stopping the driving of the blower 22 will be specifically described with reference to the flow chart shown in FIG. That is, after the blower 22 automatically starts to operate, it is determined whether the blower 22 has operated for the set time (S500), and if it is determined that the blower 22 has operated for the set time (S500, YES), it is determined whether the temperature detected by the temperature sensor 25 is below the second predetermined temperature T2 (S501), and if it is determined that the temperature is below the second predetermined temperature T2 (S501, YES), the operation of the blower 22 is stopped (S502).

[0078] When operating in the automatic operation mode, the air volume of the blower may be automatically adjusted according to the detected temperature, for example, the temperature detected by the temperature sensor 25. In addition, the driving mode can be switched from automatic to manual mode by manual operation. Furthermore, a return from the manual driving mode to the automatic driving mode occurs, for example, in the following cases. A certain amount of time has passed since the vehicle entered manual operation mode. When the fan is stopped. A certain amount of time has passed since the fan was stopped. [Explanation of symbols]

[0079] 10... cooking appliance, 11... heating section, 12... switch, 13... heating section control section, 14... transmission section, 20... range hood, 21... hood body, 22... blower, 23... operation switch, 24... control section, 25... temperature sensor.

Claims

1. A range hood equipped with a blower and a temperature sensor for detecting the temperature above a cooking device, After the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a first threshold value indicating a temperature rise state and the temperature detected by the temperature sensor is equal to or greater than a first predetermined temperature, A range hood characterized by having an automatic operation mode in which the blower is driven when a temperature gradient of the temperature detected by the temperature sensor satisfies a predetermined condition.

2. The range hood according to claim 1, The specified condition is that the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value indicating a temperature rising state.

3. The range hood according to claim 1, The specified condition is that the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value indicating a temperature rising state for a set specified time.

4. The range hood according to claim 1, The specified condition is that the temperature gradient of the temperature detected by the temperature sensor is equal to or greater than a second threshold value indicating a temperature rising state for a specified number of times or more in succession.

5. The range hood according to claim 1, The specified condition is that the temperature gradient of the temperature detected by the temperature sensor does not fall continuously below a second threshold value indicating a temperature rising state during a set specified period of time.

6. The range hood according to claim 1, The specified condition is that the temperature gradient of the temperature detected by the temperature sensor does not fall below a second threshold value indicating a temperature rising state consecutively, and the temperature gradient of the temperature detected by the temperature sensor is above the second threshold value a specified number of times or more.

7. The range hood according to any one of claims 1 to 6, The automatic operation mode drives the blower when a temperature gradient of the temperature detected by the temperature sensor exceeds a third threshold value indicating a temperature rise state a predetermined number of times during the determination of the predetermined condition, The third threshold is a threshold that indicates a temperature rise higher than the second threshold that indicates a temperature rise state when used under specified conditions.

8. The range hood according to claim 7, The automatic operation mode has a third predetermined temperature higher than the first predetermined temperature, and when a temperature rise gradient of the detected temperature of the temperature sensor exceeds the set third threshold during the determination of the predetermined condition, the temperature before the temperature rise is stored; The range hood drives the blower when the currently stored temperature exceeds the previously stored temperature a predetermined number of times while the currently stored temperature exceeds the previously stored temperature or while the temperature detected by the temperature sensor continues to be higher than the third predetermined temperature.

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