JP5116617B2 - rice cooker - Google Patents

Description

  The present invention relates to a rice cooker, and more specifically, a rice cooker provided with temperature detection means for detecting the temperature of an object to be cooked and abnormality determination means for determining whether or not the temperature detection means is abnormal. It is about a vessel.

  Conventionally, a rice cooker has been provided with a temperature sensor that contacts the bottom of the inner pot. In this rice cooker, at the time of rice cooking, the boiling state in the inner pot is sensed based on the detected temperature detected from the temperature sensor. Then, after sensing the boiling state, when it is sensed that the temperature detected by the temperature sensor has reached the rice cooking completion temperature higher than the boiling temperature, rice cooking control is performed to stop the rice cooking heating. During rice cooking control, it is always monitored whether or not the detected temperature detected from the temperature sensor has reached a preset abnormal overheating temperature. When it is determined that the detected temperature has reached the abnormal overheating temperature, the rice cooking heating is forcibly stopped, and abnormal overheating of the components in the inner pot and the rice cooker is prevented. Thereby, safety is ensured. As a cooking device (rice cooker) having such a safety function, for example, based on the presence or absence of a container (inner pot) and the temperature detected by a temperature detection means (temperature sensor), the power supply to the heating means is cut off. A cooker having a plurality of power supply control means is known (for example, see Patent Document 1).

  This type of cooker includes a first power supply control means for cutting off the power supply to the heating means while there is no container, a temperature detection means for detecting the temperature of the container, and a predetermined temperature detection means exceeding 100 ° C. A second power supply control means for cutting off the power supply to the heating means while detecting the temperature or higher is provided. According to this rice cooker, safety is ensured when there is no container by the first power supply control means, and an excessive temperature rise is prevented by the second power supply control means, so safety is ensured.

The power supply voltage monitoring means detects a power failure or voltage drop due to a lightning strike, power transmission accident, etc., and the flame detection means detects no flame during a momentary power failure or voltage drop within a predetermined time that is measured by the timer means. In such a case, a combustion control device is known in which re-ignition means works to re-ignite and continue combustion (see, for example, Patent Document 2).
JP-A-8-322714 Japanese Patent No. 3538946

  However, in such a cooker, when a power failure occurs at a high temperature, such as during boiling, and when rice cooking is resumed after the power failure is restored, the temperature rise after restarting heating is small, so the temperature is detected normally. Despite being present, there was a problem that cooking was interrupted because it was judged abnormal. As a result, the cooked state of the rice deteriorated and the convenience of the cooker user was impaired.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a rice cooker that can accurately detect abnormality of the temperature detection means even if a power failure occurs in a high temperature state.

  In order to achieve the above object, a rice cooker according to the first aspect of the present invention includes an inner pot for storing an object to be cooked, a heating means for heating the inner pot with flames, and a power supply voltage for detecting a power failure or a voltage drop. Monitoring means, timer means for counting the time of power failure or voltage drop, flame detection means for detecting the presence or absence of flame in the heating means, the power supply voltage monitoring means detects power failure or voltage drop, and the timer means Re-ignition control means for re-igniting the heating means when the flame detection means detects no flame during a power failure or voltage drop within a certain time to be timed, and temperature detection for detecting the temperature of the cooking object Means for determining whether or not heating by the heating means has been started, and measuring an elapsed time since the heating start determining means determined that heating by the heating means has been started Initial detected temperature storage means for storing an initial detected temperature that is a temperature detected by the temperature detecting means when it is determined by the heating start determining means that heating by the heating means has been started. A first predetermined time determining means for determining whether the elapsed time measured by the elapsed time measuring means has reached a first predetermined time; and the elapsed time by the first predetermined time determining means. When it is determined that one predetermined time has been reached, a first detection temperature storage means for storing a first detection temperature that is a temperature detected by the temperature detection means, and the initial detection temperature storage means stored in the first detection temperature storage means The temperature detection means is abnormal when the difference between the initial detection temperature and the first detection temperature stored in the first detection temperature storage means is equal to or less than a first predetermined value. First abnormality determining means for determining, and when the first detected temperature stored in the first detected temperature storage means is equal to or lower than a second predetermined value, a determination process by the first abnormality determining means is performed, When the first detected temperature is higher than the second predetermined value, the determination process by the first abnormality determination unit is not performed.

  Further, the rice cooker of the invention according to claim 2 includes an inner pot that accommodates an object to be cooked, a heating means that heats the inner pot with flame, a power supply voltage monitoring means that detects a power failure or a voltage drop, Timer means for counting the time of voltage drop, flame detection means for detecting the presence or absence of flame in the heating means, and the power supply voltage monitoring means detects a power failure or voltage drop, and within a certain time that the timer means times. A re-ignition control means for re-igniting the heating means when the flame detection means detects no flame during a power failure or a voltage drop, a temperature detection means for detecting the temperature of the cooking object, and the heating means Heating start determining means for determining whether or not heating has been started, and elapsed time measuring means for measuring an elapsed time from when the heating start determining means determines that heating by the heating means has been started An initial detection temperature storage means for storing an initial detection temperature which is a temperature detected by the temperature detection means when the heating start determination means determines that heating by the heating means has been started, and the elapsed time measurement A first predetermined time determining means for determining whether or not the elapsed time measured by the means has reached a first predetermined time; and the elapsed time has reached the first predetermined time by the first predetermined time determining means. A first detection temperature storage means for storing a first detection temperature that is a temperature detected by the temperature detection means, the initial detection temperature stored in the initial detection temperature storage means, A first abnormality judgment for judging that the temperature detection means is abnormal when a difference from the first detection temperature stored in the first detection temperature storage means is not more than a first predetermined value. And a boiling flag storage means for storing a boiling flag when the temperature detected by the temperature detection means has not risen for a predetermined time that can be determined to be boiling, and the boiling flag is not stored in the boiling flag storage means In this case, the determination process by the first abnormality determination unit is performed, and when the boiling flag is stored in the boiling flag storage unit, the determination process by the first abnormality determination unit is not performed. .

  Moreover, the rice cooker of the invention which concerns on Claim 3 adds to the structure of the invention of Claim 1 or 2, When the said temperature detection means is judged to be abnormal by the said 1st abnormality judgment means, First heating stop means for forcibly stopping heating by the heating means is further provided.

  Moreover, the rice cooker of the invention which concerns on Claim 4 adds to the structure of the invention in any one of Claims 1 thru | or 3, and when the said temperature detection means is judged to be abnormal by the said 1st abnormality judgment means In addition, first notification means for notifying abnormality of the temperature detection means is further provided.

  Moreover, the rice cooker of the invention which concerns on Claim 5 is further equipped with the heating start instruction | indication means which instruct | indicates the heating start with respect to the said heating means in addition to the structure of the invention in any one of Claim 1 thru | or 4, The said When the first abnormality determining means determines that the temperature detecting means is abnormal, it further includes first instruction invalidating means for invalidating a subsequent heating start instruction by the heating start instructing means.

  Moreover, the rice cooker of the invention which concerns on Claim 6 has the time measured by the said elapsed time measurement means in addition to the structure of the invention in any one of Claims 1 thru | or 5 longer than said 1st predetermined time. A second predetermined time determining means for determining whether or not the second predetermined time has been reached, and the temperature when the elapsed time is determined to have reached the second predetermined time by the second predetermined time determining means. A second detection temperature storage means for storing a second detection temperature that is a temperature detected by the detection means; and the second detection temperature stored in the second detection temperature storage means is equal to or lower than a predetermined temperature. Second abnormality determining means for determining that the temperature detecting means is abnormal is further provided.

  Moreover, the rice cooker of the invention which concerns on Claim 7 adds to the structure of the invention of Claim 6, and when the said temperature detection means is judged to be abnormal by the said 2nd abnormality judgment means, the said heating means There is further provided a second heating stop means for forcibly stopping the heating.

  Moreover, the rice cooker of the invention which concerns on Claim 8 adds to the structure of the invention of Claim 6 or 7, In addition, when it is judged by the said 2nd abnormality judgment means that the said temperature detection means is abnormal, Second notifying means for notifying abnormality of the temperature detecting means is further provided.

  Moreover, the rice cooker of the invention which concerns on Claim 9 is added to the structure of the invention in any one of Claims 6 thru | or 8, When the said temperature detection means is judged to be abnormal by the said 2nd abnormality judgment means In addition, there is further provided second instruction invalidating means for invalidating a heating start instruction by the heating start instructing means thereafter.

  In the rice cooker of the invention according to claim 1, the power supply voltage monitoring means detects a power outage or voltage drop, and the flame detection means detects that there is no flame during a power outage or voltage drop within a certain time measured by the timer means. In this case, the reignition control means can reignite the heating means. And the to-be-cooked object temperature accommodated in the inner pot is detected by the temperature detection means. When an instruction to start heating is given by the heating start instruction means, heating of the inner pot by the heating means is started. The start of heating is determined by the heating start determining means. When it is determined that heating has been started, or when it is determined that an instruction to start heating has been issued, the initial detected temperature, which is the temperature detected by the temperature detecting means, is stored in the initial detected temperature storage means. . Further, the elapsed time is measured by the elapsed time measuring means when it is determined that the heating is started or when it is determined that the heating start instruction is issued. Next, it is determined by the first predetermined time determination means whether or not the elapsed time has reached the first predetermined time. If the first predetermined time determining means determines that the first predetermined time has been reached, the first detected temperature, which is the temperature detected by the temperature detecting means when the first predetermined time is reached, is the first detected temperature storage means. Is remembered. When the difference between the initial detected temperature and the first detected temperature is equal to or less than a predetermined value, the first abnormality determining unit determines that the temperature detecting unit is abnormal. When the temperature detection means is normal, the first detection temperature is expected to rise above a predetermined value with respect to the initial detection temperature. However, when there is an abnormality in the temperature detection means or when there is an abnormality in the installation state of the temperature detection means, a temperature increase greater than a predetermined value expected when the temperature detection means is normal is not detected. In the rice cooker of the present invention, when the difference between the first detection temperature and the initial detection temperature is equal to or less than a predetermined value by the first abnormality determination unit, it is determined that the temperature detection unit is abnormal. Can be detected easily and quickly. Moreover, in the rice cooker of this invention, when the 1st detection temperature memorize | stored in the 1st detection temperature memory | storage means is below 2nd predetermined value, the judgment process by a 1st abnormality determination means is performed, and the said 1st detection temperature Is higher than the second predetermined value, the determination processing by the first abnormality determination means is not performed. Therefore, if a power failure occurs when the temperature is high, such as during boiling, and the heating is resumed after the recovery from the power failure, the temperature rise after restarting the heating is small. It can prevent judging and interrupting cooking rice. Therefore, safety can be improved without impairing the usability of the rice cooker.

  Moreover, in the rice cooker of the invention which concerns on Claim 2, a power supply voltage monitoring means detects a power failure or a voltage drop, and the said flame detection means does not have a flame during the power failure or voltage drop within the fixed time which a timer means time-measures. When this is detected, the reignition control means can reignite the heating means. And the to-be-cooked object temperature accommodated in the inner pot is detected by the temperature detection means. When an instruction to start heating is given by the heating start instruction means, heating of the inner pot by the heating means is started. The start of heating is determined by the heating start determining means. When it is determined that heating has been started, or when it is determined that an instruction to start heating has been issued, the initial detected temperature, which is the temperature detected by the temperature detecting means, is stored in the initial detected temperature storage means. . Further, the elapsed time is measured by the elapsed time measuring means when it is determined that the heating is started or when it is determined that the heating start instruction is issued. Next, it is determined by the first predetermined time determination means whether or not the elapsed time has reached the first predetermined time. If the first predetermined time determining means determines that the first predetermined time has been reached, the first detected temperature, which is the temperature detected by the temperature detecting means when the first predetermined time is reached, is the first detected temperature storage means. Is remembered. When the difference between the initial detected temperature and the first detected temperature is equal to or less than a predetermined value, the first abnormality determining unit determines that the temperature detecting unit is abnormal. When the temperature detection means is normal, the first detection temperature is expected to rise above a predetermined value with respect to the initial detection temperature. However, when there is an abnormality in the temperature detection means or when there is an abnormality in the installation state of the temperature detection means, a temperature increase greater than a predetermined value expected when the temperature detection means is normal is not detected. In the rice cooker of the present invention, when the difference between the first detection temperature and the initial detection temperature is equal to or less than a predetermined value, the first abnormality determination unit determines that there is an abnormality in the temperature detection unit, and detects by the temperature detection unit. When the temperature does not rise for a predetermined time that can be determined to be boiling, a boiling flag is stored in the boiling flag storage means. When the boiling flag is not stored in the boiling flag storage means, a determination process is performed by the first abnormality determination means. When the boiling flag is stored in the boiling flag storage means, the second flag is stored. Since the determination process by the first abnormality determination unit is not performed, once the boiling occurs, the determination process by the first abnormality determination unit is not performed unnecessarily. Therefore, if a power failure occurs when the temperature is high, such as during boiling, and the heating is resumed after the recovery from the power failure, the temperature rise after restarting the heating is small. It can prevent judging and interrupting cooking rice. Therefore, safety can be improved without impairing the usability of the rice cooker.

  Moreover, in the rice cooker of the invention which concerns on Claim 3, in addition to the effect of the invention of Claim 1 or 2, when it is judged by the 1st abnormality judgment means that a temperature detection means is abnormal, 1st heating The heating by the heating means can be forcibly stopped by the stop means. Therefore, safety can be further improved without impairing the usability of the rice cooker.

  Moreover, in the rice cooker of the invention which concerns on Claim 4, in addition to the effect of the invention in any one of Claims 1 thru | or 3, when it is judged by the 1st abnormality judgment means that a temperature detection means is abnormal, Since the notification is made by the first notification means, the user can know that the temperature detection means is abnormal. Therefore, it is possible to avoid a situation where the user cooks without noticing the abnormality of the temperature detecting means. Therefore, safety can be further improved without impairing the usability of the rice cooker.

  Moreover, in the rice cooker of the invention which concerns on Claim 5, in addition to the effect of the invention in any one of Claims 1 thru | or 4, when it is judged by the 1st abnormality judgment means that the temperature detection means is abnormal The subsequent heating start instruction is invalidated by the first instruction invalidating means. Thus, even when the user gives a heating start instruction without noticing that the temperature detecting means is abnormal, heating is not started. Therefore, a rice cooker with higher safety can be provided without impairing the usability of the rice cooker.

  Moreover, in the rice cooker of the invention which concerns on Claim 6, in addition to the effect of the invention in any one of Claims 1 thru | or 5, the elapsed time from a heating start is made into 2nd predetermined time by the 2nd predetermined time judgment means. It is determined whether it has been reached. If it is determined that the elapsed time has reached the second predetermined time, the second detected temperature, which is the temperature detected by the temperature detecting means when the second predetermined time is reached, is stored in the second detected temperature storage means. Remembered. When the second detected temperature is equal to or lower than the predetermined temperature, the second abnormality determining unit determines that the temperature detecting unit is abnormal. Generally, the temperature detected by the temperature detecting means is expected to be higher than the predetermined temperature when the second predetermined time has elapsed since the start of heating. However, when there is an abnormality in the temperature detection means or when there is an abnormality in the installation state of the temperature detection means, the detected temperature is equal to or lower than a predetermined temperature expected when it is normal. In the rice cooker of the present invention, when the second detection temperature is equal to or lower than the predetermined temperature by the second abnormality determination unit, it is determined that the temperature detection unit is abnormal, so that the malfunction of the temperature detection unit can be detected easily and accurately. can do. Therefore, the safety of the rice cooker can be improved. Moreover, even if the degree of abnormality of the temperature detection means is mild (not extreme abnormality) that the first abnormality determination means does not detect, it can be determined that the temperature detection means is abnormal. Therefore, safety can be further improved without impairing the usability of the rice cooker.

  Moreover, in the rice cooker of the invention which concerns on Claim 7, in addition to the effect of the invention of Claim 6, when a 2nd abnormality judgment means judges that a temperature detection means is abnormal, a 2nd heating stop Since the heating is forcibly stopped by the means, abnormal overheating of the inner pot and parts of the rice cooker can be reliably prevented. Therefore, safety can be further improved without impairing the usability of the rice cooker.

  Further, in the rice cooker of the invention according to claim 8, in addition to the effect of the invention of claim 6 or 7, when the second abnormality determination means determines that the temperature detection means is abnormal, the second notification Since the notification is performed by the means, the user can know that the temperature detection means is abnormal. Therefore, it is possible to avoid the situation where the user cooks without noticing the abnormal state of the temperature detecting means. Thus, the safety can be further improved without impairing the usability of the rice cooker.

  Further, in the rice cooker of the invention according to claim 9, in addition to the effect of the invention according to any of claims 6 to 8, when the temperature detection means is determined to be abnormal by the second abnormality determination means The subsequent heating start instruction is invalidated by the second instruction invalidating means. Thus, even when the user gives a heating start instruction without noticing that the temperature detecting means is abnormal, heating is not started. Therefore, a rice cooker with higher safety can be provided without impairing usability.

  Hereinafter, rice cooker 1 which is one embodiment of the present invention is explained with reference to drawings. FIG. 1 is a schematic configuration diagram of a rice cooker 1. FIG. 2 is a graph comparing changes over time in the detected temperature detected by the temperature sensor 9 when rice cooking control is performed under various conditions.

  First, the structure of the rice cooker 1 will be schematically described. As shown in FIG. 1, a rice cooker 1 includes an inner pot 2 for containing rice and water, a cylindrical casing (not shown) in which the inner pot 2 is detachably housed, and a pivoted inner casing. An inner lid 3 that opens and closes the upper opening of the pot 2 and a burner 4 that heats the inner pot 2 by burning gas are provided. The rice cooker 1 also includes a temperature sensor 9 that detects the temperature of the bottom of the inner pot 2 and a controller 12 that controls the combustion of the burner 4 based on the temperature detected by the temperature sensor 9.

  An igniter 24 that ignites the burner 4 and a frame rod 25 that detects that the burner has ignited are provided in the vicinity of the burner 4. The gas supply path 5 for supplying gas to the burner 4 is provided with an original electromagnetic valve 6 for opening and closing the gas flow path, and a branching portion 27 and a merging portion 28 are upstream of the original electromagnetic valve 6. In order. One end portion of the bypass 31 is connected to the branch portion 27, and the other end portion of the bypass 31 is connected to the junction portion 28. Therefore, the gas flowing through the gas supply path 5 is divided into two flow paths at the branching section 27, merged again at the merge section 28, and supplied to the burner 4. A first electromagnetic valve 7 is provided between the branching portion 27 and the merging portion 28 of the gas supply path, and a second electromagnetic valve 8 is provided in the bypass 31. In such a configuration, when the burner 4 is burned with a strong fire, both the first electromagnetic valve 7 and the second electromagnetic valve 8 are opened. On the other hand, when burning with low heat, only the first electromagnetic valve 7 is opened and the second electromagnetic valve 8 is closed. In this way, the heating power in the burner 4 is controlled.

  The temperature sensor 9 is provided in the center of the burner 4 accommodated in the casing. This temperature sensor 9 detects the bottom temperature of the inner hook 2 by contacting the center of the bottom of the inner hook 2 set in the casing. That is, since the temperature of the cooking object in the inner pot 2 cannot be directly detected, the temperature of the cooking object is indirectly detected by detecting the pot bottom temperature. The temperature sensor 9 has a temperature sensing part 91 constituted by a thermistor and a lead wire 92. Further, since the temperature sensor 9 is electrically connected to the controller 12, the controller 12 can receive a temperature data signal detected by the temperature sensor 9.

  The controller 12 is provided with a microcomputer 19 that controls the main control of the rice cooker 1. The microcomputer 19 includes a CPU 13 that is a central processing unit, a ROM 14, and a RAM 15. The ROM 14 stores a control program executed by the CPU 13, and the RAM 15 stores a detected temperature, a boiling flag, and the like, which will be described later. The microcomputer 19 is connected to an EEPROM 16, a flash memory 18, a clock IC 17, a secondary battery 42, and an I / O interface (not shown) provided outside the microcomputer 19. As the secondary battery 42, a lithium ion secondary battery, a lithium ion polymer secondary battery, a nickel / hydrogen storage battery, a nickel / cadmium storage battery, or the like can be used. Further, as the secondary battery 42, a large capacity electric field capacitor or the like may be used.

  The watch IC 17 measures the elapsed time from the start of heating in the rice cooking process and the elapsed time (power failure time) after the power supply voltage becomes less than a predetermined value. Further, the secondary battery 42 supplies power to the microcomputer 19 at the time of a power failure. Further, a power supply circuit 40 is connected to the microcomputer 19 so that driving power is supplied, and the secondary battery 42 can be charged from the power supply circuit 40 via the charging circuit 41. It has become. A power cord 44 for acquiring power is connected to the power circuit 40. The controller 12 having the above-described configuration is configured so that the original solenoid valve 6, the first solenoid valve 7, the second solenoid valve 8, the display screen 20 provided on the operation panel 11, and various display lamps according to a program stored in the ROM 14 in advance. (Not shown).

  An operation panel 11 is provided on the outer periphery of the casing. As shown in FIG. 1, the operation panel 11 includes a display screen 20 including a 7-segment display and various input buttons. Here, the display screen 20 can use another display device such as an LCD. Moreover, as an input button, the time adjustment button 21 for a user to adjust the present | current time and the rice cooking end time, and the rice cooking button 22 are provided.

  In addition, since the rice cooker 1 is equipped with EEPROM16 which is a rewritable non-volatile memory in the controller 12, the information regarding the rice cooker 1 before power-off, etc. are memorize | stored when the power supply is cut | disconnected.

  Next, the time-dependent change of the bottom temperature during rice cooking control under various conditions will be described with reference to FIG. FIG. 2 is a graph comparing changes over time in the bottom temperature during rice cooking control under various conditions. In the rice cooker 1, when rice cooking control is started, the temperature of the bottom of the inner pot 2 is always detected by the temperature sensor 9, and monitoring is performed in real time. Based on the detected temperature Q monitored by the temperature sensor 9, the heating power of the burner 4 is adjusted and normal rice cooking is performed. Therefore, the time-dependent change of the detected temperature Q detected by the normal temperature sensor 9 will be described with reference to the curves a and b, and the time-dependent change of the detected temperature Q when the temperature detection by the temperature sensor 9 fails. This will be described with reference to the curves b and c.

  First, the curve a will be described. A curve a is a change with time of a detected temperature Q detected by a normal temperature sensor 9 in general rice cooking control. First, when the rice cooking button 22 is pressed, the original solenoid valve 6, the first solenoid valve 7, and the second solenoid valve 8 are opened, and the burner 4 is ignited to start heating the inner pot 2 ( Time: 0). Then, the detected temperature Q continues to rise gently until the inside of the inner pot 2 reaches a boiling state (period: A).

  Then, at the stage where a first predetermined time t1 (for example, 5 minutes) has elapsed since the start of heating, the detected temperature Q shows an increase value that is greater than a predetermined value Δγ (for example, 5 ° C.). Furthermore, when the second predetermined time t2 (for example, 15 minutes) has elapsed, the temperature becomes higher than the second predetermined temperature P2 (for example, 50 ° C.). Next, when the inside of the inner pot 2 is in a boiling state, the combustion heat transmitted from the burner 4 to the inner pot 2 is used for evaporation of water in the inner pot 2. For this reason, the detected temperature Q by the temperature sensor 9 is substantially constant (period: B). During this period, only the second solenoid valve 8 is closed, and the heating power is changed from high to low.

  Further, when the evaporation of water proceeds and the amount of water in the inner pot 2 decreases, the combustion heat transmitted from the burner 4 to the inner pot 2 is accumulated in the inner pot 2, so that the detected temperature Q is again It rises (period: C). When the detected temperature Q reaches the rice cooking completion temperature P3, all of the original solenoid valve 6, the first solenoid valve 7, and the second solenoid valve 8 are closed, and the burner 4 is extinguished. Thus, the rice cooking control of the rice cooker 1 is completed.

  Next, the curve b will be described. A curve b is a change with time of the detected temperature Q when the rice cooking control is performed in a so-called “empty cooking state” in which the inner pot 2 is not fixed in the casing. First, when the rice cooking button 22 is pressed and heating is started (time: 0), since the inner pot 2 is not in contact with the temperature sensor 9, there is no heat drawn from the temperature sensor 9 to the inner pot 2 and the detected temperature. Q rises rapidly. Here, in the rice cooker 1, it is constantly monitored whether or not the detected temperature Q detected by the temperature sensor 9 has reached a preset abnormal superheat temperature P4. When the detected temperature Q reaches the abnormal overheat temperature P4, it is determined that the inner hook 2 is in an abnormal overheat state. In this case, all of the original solenoid valve 6, the first solenoid valve 7, and the second solenoid valve 8 are forcibly closed, and the heating by the burner 4 is terminated. Thereby, it can prevent that the components in the casing of the rice cooker 1 will be in an overheated state.

  Next, the curve c will be described. A curve c is a change over time of the detected temperature Q detected by the temperature sensor 9 when the rice cooking process is started in a state where the temperature sensor 9 is disconnected or short-circuited. First, when the rice cooking button 22 is pressed and heating is started (time: 0), the temperature sensor 9 is disconnected or short-circuited. Therefore, even if the temperature of the inner pot 2 rises, the detected temperature Q rises. It shows almost a constant value. Accordingly, the detected temperature Q is heated even when the first predetermined time t1 (for example, 5 minutes) and the second predetermined time t2 (for example, 15 minutes) have elapsed since the start of heating of the inner pot 2. Regardless of whether or not, it shows a substantially constant value. Therefore, in the present embodiment, when the detected temperature Q is equal to or less than the predetermined value Δγ when the first predetermined time t1 has elapsed since the heating of the inner pot 2 is started, It is determined that the temperature detection by the temperature sensor 9 is abnormal. Thereby, the abnormality of the temperature sensor 9 can be detected quickly.

  Next, the curve d will be described. Curve d shows a rice cooking process in a state in which foreign matter is sandwiched between the temperature sensor 9 and the inner pot 2, or in a state in which the contact state between the temperature sensor 9 and the inner pot 2 has changed due to a change in dimensions with time. Is a time-dependent change of the detected temperature Q detected by the temperature sensor 9 when the operation is started. In this case, since the detection accuracy of the temperature sensor 9 is deteriorated, a temperature lower than the actual temperature of the inner hook 2 is detected. The difference between the detected temperature Q and the actual temperature of the inner pot 2 increases as the heating time increases.

  For example, when the first predetermined time t1 (for example, 5 minutes) has elapsed from the start of heating (time: 0), the detected temperature Q is the same as the temperature sensor 9 (see curve a) that is operating normally. An increase value larger than a predetermined value Δγ (for example, 5 ° C.) with respect to the detected temperature Q0 is shown. However, at the stage where the second predetermined time t2 (for example, 15 minutes) has elapsed since the start of heating, the curve a is higher than the second predetermined temperature P2 (for example, 50 ° C.), whereas the curve d has the first 2 The predetermined temperature P2 has not been reached. Therefore, in the present embodiment, even if the detected temperature Q shows an increase value greater than the predetermined value Δγ when the first predetermined time t1 has elapsed since the start of heating, the second predetermined time when the second predetermined time t2 has elapsed. When the temperature is equal to or lower than P2, it is determined that the temperature detection by the temperature sensor 9 is abnormal. Thereby, the abnormality of the temperature sensor 9 can be detected quickly.

  Thus, in the rice cooker 1, the detected temperature Q (initial detected temperature Q0) of the temperature sensor 9 at the start of heating and the detected temperature Q (first detected temperature Q1) after the first predetermined time t1 has elapsed from the start of heating. ) Is less than or equal to a predetermined value Δγ, it is determined that the temperature sensor 9 is abnormal. Further, when the detected temperature Q (second detected temperature Q2) at the stage when the second predetermined time t2 has elapsed is equal to or lower than the second predetermined temperature P2, it is determined that the temperature sensor 9 is abnormal.

  Next, the power failure process will be described with reference to FIGS. FIG. 3 is a flowchart of the power failure process executed by the microcomputer 19 as the power failure process. FIG. 4 is a conceptual diagram showing a power supply state before a power failure (a state where power is normally supplied). FIG. 5 is a conceptual diagram of processing immediately before a power failure (a state where the voltage from the outlet becomes less than a specified value). FIG. 6 is a conceptual diagram of processing during a power failure. FIG. 7 is a conceptual diagram of processing in a state where power is restored from a power failure (a state where the voltage from the outlet becomes less than a specified value).

  Note that the power failure processing program in the flowchart shown in FIG. 3 is executed at predetermined time intervals (as an example, 2 ms intervals) by the microcomputer 19 as interrupt processing. When the power supply voltage supplied from the power supply circuit 40 is normal, a normal voltage power supply is supplied from the power supply circuit 40 to the microcomputer 19, the EEPROM 16, the secondary battery 42, and the clock IC 17, as shown in FIG. Yes. Next, when the microcomputer 19 detects that the voltage of the power source supplied from the power source circuit 40 has become less than a predetermined value (S21: YES), the clock IC 17 measures the time during which the power source voltage has decreased. Time measurement is started (S22). Next, as shown in FIG. 5, data is saved from the RAM 15 of the microcomputer 19 to the EEPROM 16 (S23). Next, the timepiece IC 17 is driven by the supply of power from the secondary battery 42 (S24). Next, as shown in FIG. 6, even when a power failure occurs and the supply of power from the power supply circuit 40 is stopped, the timepiece IC 17 is continuously driven by the supply of power from the secondary battery 42. When the power failure is resolved and the power supply voltage from the power supply circuit 40 is restored to a predetermined value or higher (S25: YES), the data saved in the EEPROM 16 is transferred to the RAM 15 of the microcomputer 19 to restore the data (S26). ). Therefore, a boiling flag or the like, which will be described later, is also stored in the EEPROM 16 during a power failure, and is stored in the RAM 15 after the power failure is recovered.

  Next, when it is determined that the power supply voltage has become less than the predetermined value (S21: YES) and the recovery of the power supply voltage is within a predetermined time (for example, within 7 minutes) (S27: NO), there is no flame. In the case and when detected by the frame rod 25 (S28: NO), the igniter 24 reignites the burner 4 (S29). If the time from when it is determined that the power supply voltage has become less than the predetermined value (S21: YES) to the recovery of the power supply voltage has passed a predetermined time (for example, 7 minutes or more have passed) (S27: YES) ), The burner 4 is not re-ignited and the process returns to the determination process of S21.

  Next, temperature sensor abnormality detection processing by the CPU 13 after resuming rice cooking after recovery of power supply voltage (after recovery from power failure) will be described with reference to the flowchart shown in FIG. When the rice cooking button 22 is pressed by the user, the temperature sensor abnormality detection process by the CPU 13 is started together with the start of the rice cooking control process. In the temperature sensor abnormality detection process, first, the detected temperature Q of the temperature sensor 9 when the rice cooking button 22 is operated is stored in the RAM 15 as the initial detected temperature Q0 (S1). Next, it is determined whether or not the burner 4 is in an ignition state (S2). Whether or not the burner 4 is in an ignition state is determined by whether or not flame is detected by the frame rod 25. If no flame is detected by the frame rod 25, it is determined that the ignition state is not established (S2: NO), and the process of S2 is performed again.

  When it is determined that the burner 4 is in an ignition state (S2: YES), measurement by the clock IC 17 is started (S3). Subsequently, it is determined whether or not the elapsed time from the start of measurement has reached the first predetermined time t1 (S4). When it is determined that the elapsed time from the start of measurement has not reached the first predetermined time t1 (S4: NO), the process of S4 is repeated until it is determined that the first predetermined time t1 has been reached. Done.

  When it is determined that the elapsed time from the start of measurement has reached the first predetermined time t1 (S4: YES), the detected temperature Q detected by the temperature sensor 9 is stored in the RAM 15 as the first detected temperature Q1. (S5). Then, it is determined whether or not the first detected temperature Q1 stored in the RAM 15 is equal to or lower than a first predetermined temperature P1 (for example, 60 ° C.) (S6). When it is determined that the first detected temperature Q1 is equal to or lower than the first predetermined temperature P1 (S6: YES), the difference between the first detected temperature Q1 and the initial detected temperature Q0 is calculated, and the difference is equal to or smaller than the predetermined value Δγ. Is determined (S7).

  As described above, when the temperature sensor 9 is short-circuited or disconnected, the difference between the first detection temperature Q1 and the initial detection temperature Q0 is equal to or less than the predetermined value Δγ. In the present embodiment, when the difference between the first detection temperature Q1 and the initial detection temperature Q0 is equal to or less than the predetermined value Δγ (S7: YES), it is stored in the flash memory 18 that the temperature sensor 9 is abnormal (S11). ). By performing the process of S11, for example, the contents stored in the flash memory 18 at the time of inspection can be read and used for maintenance.

  Next, by generating a buzzer from the speaker 23, it is notified that the temperature sensor 9 is abnormal (S12). Thereby, the user can know that the temperature sensor 9 is abnormal.

  When the process of S12 is performed, the supply of gas to the burner 4 is shut off by forcibly closing the original solenoid valve 6, the first solenoid valve 7, and the second solenoid valve 8 (S13). By performing the process of S13, even when the user does not notice the abnormality of the temperature sensor 9, the combustion of the burner 4 can be terminated. Therefore, abnormal overheating of the inner hook 2 can be reliably prevented, and safety can be further improved.

  Next, a process of prohibiting driving of the igniter 24 for igniting the burner 4 is performed (S14). By performing the process of prohibiting the driving of the igniter 24, the burner 4 is not re-ignited even when the user subsequently presses the rice cooking button 22. Therefore, even when the user performs the ignition operation again without noticing the abnormality of the temperature sensor 9, the burner 4 is not re-ignited, and the safety can be further improved. When the process of S14 ends, the temperature sensor abnormality detection process ends.

  On the other hand, if it is determined in S6 that the first detected temperature Q1 is not equal to or lower than the first predetermined temperature P1 (S6: NO), the process proceeds to S8 without making the determination in S7. For example, when a power failure occurs, the rice cooking process and the temperature sensor abnormality detection process are temporarily interrupted even during rice cooking. And a rice cooking process and a temperature sensor abnormality detection process are restarted when a user presses the rice cooking button 22 (refer FIG. 1) after a power failure recovery. When a power failure occurs when the state in the inner pot 2 is in a boiling state (period B in FIG. 2), or when the power failure period is short, when the temperature sensor abnormality detection process is started, The pot 2 is already hot. In this case, even if the temperature sensor 9 is normal, the difference between the initial detection temperature Q0 and the first detection temperature Q1 may be equal to or less than the predetermined value Δγ. That is, when the process of S7 is performed in a state where the inner hook 2 is already at a high temperature, it may be determined that the temperature sensor 9 is abnormal although the temperature sensor 9 is normal. In the present embodiment, when it is determined in S6 that the first detected temperature Q1 is not equal to or lower than the first predetermined temperature P1 (S6: NO), the process of S7 is not performed, so that the abnormality of the temperature sensor 9 is detected. It is possible to prevent erroneous detection. Thereby, safety | security can be improved, without impairing the usability of the rice cooker 1. FIG.

  In S7, if the difference between the first detected temperature Q1 and the initial detected temperature Q0 is not less than or equal to the predetermined value Δγ (S7: NO), it is determined whether or not the elapsed time from the start of measurement has reached the second predetermined time t2. (S8). If it is determined that the elapsed time from the start of measurement has not reached the second predetermined time t2 (S8: NO), the process of S8 is repeated until it is determined that the second predetermined time t2 has been reached. Done.

  When it is determined that the elapsed time from the start of measurement has reached the second predetermined time t2 (S8: YES), the detected temperature Q detected by the temperature sensor 9 is stored in the RAM 15 as the second detected temperature Q2. (S9). Then, it is determined whether or not the second detected temperature Q2 is equal to or lower than a second predetermined temperature P2 (for example, 50 ° C.) (S10). When it is determined that the second detected temperature Q2 is equal to or lower than the second predetermined temperature P2 (S10: YES), it is stored in the flash memory 18 that the temperature sensor 9 is abnormal (S11). Next, by generating a buzzer from the speaker 23, it is notified that the temperature sensor 9 is abnormal (S12). Then, the supply of gas to the burner 4 is shut off by forcibly closing the original solenoid valve 6, the first solenoid valve 7, and the second solenoid valve 8 (S13). Further, processing for prohibiting driving of the igniter 24 for igniting the burner 4 is performed (S14). By performing the process of prohibiting the driving of the igniter 24, the burner 4 is not re-ignited even when the user subsequently presses the rice cooking button 22. When the process of S14 ends, the temperature sensor abnormality detection process ends. If it is determined in S10 that the second detected temperature Q2 is not equal to or lower than the second predetermined temperature P2 (S10: NO), the temperature sensor abnormality detection process is also terminated.

  As described above, in the rice cooker 1 of the present embodiment, when the rice cooking button 22 is pressed, the temperature sensor abnormality detection process is started simultaneously with the rice cooking process. In the case of the normal temperature sensor 9, the detected temperature Q is higher than the predetermined value Δγ when the first predetermined time t1 has elapsed from the start of heating. In the present embodiment, the detection temperature Q (initial detection temperature Q0) of the temperature sensor 9 at the start of heating and the detection temperature Q (first detection temperature Q1) when the first predetermined time t1 has elapsed from the start of heating. A difference is calculated, and it is determined whether or not the difference is equal to or less than a predetermined value Δγ. When the difference is equal to or smaller than the predetermined value Δγ, it is determined that the temperature sensor 9 is abnormal. Thereby, the abnormality of the temperature sensor 9 can be determined easily and accurately, and the safety of the rice cooker 1 can be improved. Moreover, in the present embodiment, since the first predetermined time t1 is set to 5 minutes, the abnormality of the temperature sensor 9 can be detected quickly, and the safety can be further improved.

  In the case of the normal temperature sensor 9, the detected temperature Q becomes higher than the second predetermined temperature P2 when the second predetermined time t2 has elapsed from the start of heating. In the present embodiment, it is determined that the temperature sensor 9 is abnormal when the detected temperature Q (second detected temperature Q2) after the second predetermined time t2 has elapsed from the start of heating is equal to or lower than the second predetermined temperature P2. Is done. Therefore, for example, when the contact state between the temperature sensor 9 and the inner hook 2 is changed due to a change in dimensions over time due to use, or the temperature resistance characteristics of the temperature sensing portion 91 constituting the temperature sensor 9 with use. Even when the abnormality of the temperature sensor 9 is not extreme, such as when the temperature changes, the abnormality of the temperature sensor 9 can be reliably detected. Thereby, the safety | security of the rice cooker 1 can be improved further.

  Moreover, when it is determined that the temperature sensor 9 is abnormal, the fact that the temperature sensor 9 is abnormal is stored in the flash memory 18. By reading the contents stored in the flash memory 18 as necessary, past abnormalities can be grasped, which can be used for maintenance.

  When it is determined that the temperature sensor 9 is abnormal, a buzzer is generated from the speaker 23 to let the user know that the temperature sensor 9 is in an abnormal state. Thereby, it can avoid that a user cooks without noticing the abnormal state of the temperature sensor 9, and safety can be improved.

  Further, when it is determined that the temperature sensor 9 is in an abnormal state, the igniter 24 is not driven even if the user performs an ignition operation on the burner 4 thereafter. As a result, even when the user performs an ignition operation without noticing that the temperature sensor 9 is in an abnormal state, it is not ignited in the abnormal state, and safety can be further improved.

  Further, when it is determined that the temperature sensor 9 is in an abnormal state, a process for closing the original electromagnetic valve 6, the first electromagnetic valve 7, and the second electromagnetic valve 8 is performed even during cooking. Thereby, when the temperature sensor 9 has an abnormality, the heating of the inner pot 2 is forcibly interrupted. Therefore, abnormal overheating of the inner pot 2 and parts of the rice cooker 1 is reliably prevented, and safety can be further improved.

In addition, when it is determined that the first detected temperature Q1 is not equal to or lower than the first predetermined temperature P1, it is not determined whether or not the difference between the initial detected temperature Q0 and the first detected temperature Q1 is equal to or lower than the predetermined value Δγ. For example, if a power failure occurs when the state in the inner pot 2 is in a boiling state (period B in FIG. 2), the inner pot 2 is already at a high temperature when the temperature sensor abnormality detection process is started. Yes. In this case, even if the temperature sensor 9 is normal, the difference between the initial detection temperature Q0 and the first detection temperature Q1 may be equal to or less than the predetermined value Δγ. In the present embodiment, if it is determined that the first detected temperature Q1 is not equal to or lower than the first predetermined temperature P1, whether or not the difference between the initial detected temperature Q0 and the first detected temperature Q1 is equal to or lower than the predetermined value Δγ. No judgment is made. Therefore, it is possible to prevent the abnormality of the temperature sensor 9 from being erroneously detected.

  The burner 4 shown in FIG. 1 corresponds to “heating means” of the present invention, the temperature sensor 9 corresponds to “temperature detection means” of the present invention, and the frame rod 25 corresponds to “flame detection means” of the present invention. To do. Further, in S1 of the flowchart shown in FIG. 3, the RAM 15 that stores the initial detected temperature Q0 corresponds to the “initial detected temperature storage means” of the present invention. In S <b> 2, the CPU 13 that determines whether or not heating by the burner 4 is performed corresponds to the “heating start determination unit” of the present invention. The clock IC 17 corresponds to “timer means” and “elapsed time measuring means”. In S4, the CPU 13 that determines whether or not the time measured by the clock IC 17 has reached the first predetermined time t1 corresponds to the “first predetermined time determination means” of the present invention. The RAM 15 that stores the first detected temperature Q1 in S5 corresponds to the “first detected temperature storage means” of the present invention. In S7, the CPU 13 that calculates the difference between the first detection temperature Q1 and the initial detection temperature Q0 and determines whether or not the difference is equal to or smaller than the predetermined value Δγ corresponds to the “first abnormality determination unit” of the present invention. To do.

  In S8, the CPU 13 that determines whether or not the time measured by the clock IC 17 has reached the second predetermined time t2 corresponds to the “second predetermined time determination means” of the present invention. The RAM 15 that stores the second detected temperature Q2 in S9 corresponds to the “first detected temperature storage means” of the present invention. In S10, the CPU 13 that determines whether or not the second detected temperature Q2 is equal to or lower than the second predetermined temperature P2 corresponds to the “second abnormality determining means” of the present invention.

  When it is determined in S7 that the difference is equal to or smaller than the predetermined value Δγ, the CPU 13 that performs processing for generating a buzzer from the speaker 23 in S12 corresponds to the “first notification unit” of the present invention. When it is determined in S10 that the second detected temperature Q2 is equal to or lower than the second predetermined temperature P2, the CPU 13 that performs processing for generating a buzzer from the speaker 23 in S12 corresponds to the “second notification unit” of the present invention. . The CPU 13 that starts the rice cooking control when the rice cooking button 22 shown in FIG. 1 or the rice cooking button 22 is pressed corresponds to the “heating start instruction means” of the present invention.

  When it is determined in S7 that the difference is equal to or smaller than the predetermined value Δγ, in S13, the original solenoid valve 6, the first solenoid valve 7, and the second solenoid valve 8 are closed to shut off the gas supply to the burner 4. CPU13 which performs the process to valve corresponds to the "1st heating stop means" of this invention. When it is determined in S10 that the second detected temperature Q2 is equal to or lower than the second predetermined temperature P2, in S13, the original solenoid valve 6, the first solenoid valve 7, and the first solenoid valve 7 are used to shut off the gas supply to the burner 4. CPU13 which performs the process which closes 2 solenoid valve 8 is equivalent to the "2nd heating stop means" of this invention.

  When it is determined in S7 that the difference is equal to or smaller than the predetermined value Δγ, the CPU 13 that performs the process of prohibiting the driving of the igniter 24 for igniting the burner 4 in S14 corresponds to the “first instruction invalidating means” of the present invention. To do. When it is determined in S10 that the second detected temperature Q2 is equal to or lower than the second predetermined temperature P2, the CPU 13 that performs the process of prohibiting the driving of the igniter 24 for igniting the burner 4 in S14 is “second” This corresponds to “instruction invalidation means”. Further, the CPU 13 that executes the processes of S27, S28, and S29 in the flowchart shown in FIG. 3 corresponds to the “reignition control means” of the present invention.

  The rice cooker of this invention is not limited to the rice cooker 1 of the said embodiment, A various change is possible. First, in this Embodiment, although the rice cooker 1 is a gas rice cooker, you may apply to an electric rice cooker. The time measurement by the clock IC 17 is started after it is determined that the ignition state is set (S2: YES) (S3), but may be started after the rice cooking button 22 is pressed (START). .

  Further, the temperature sensor 9 is not limited to a sensor that abuts on the bottom of the inner pot 2 and indirectly detects the temperature of the object to be cooked. For example, a temperature sensor that is provided in the vicinity of the inner lid 3 and detects the temperature of the steam generated from the inner hook 2 may be provided. Moreover, the temperature sensor provided in the rice cooker 1 is not limited to one, You may provide multiple.

  In the present embodiment, the first predetermined time t1 is 5 minutes, the second predetermined time t2 is 15 minutes, the predetermined value Δγ is 5 ° C., the first predetermined temperature P1 is 60 ° C., and the second predetermined temperature. P2 is set to 50 ° C., but these values can be appropriately adjusted. For example, it may be set according to the region of use at the time of assembly in a factory.

  Further, in the present embodiment, in order to prohibit reignition after the temperature sensor 9 is determined to be abnormal, in S14, processing for prohibiting igniter driving is performed. However, as processing for prohibiting reignition, Is not limited to prohibiting the driving of the igniter. For example, even when the user presses the rice cooking button 22, a setting may be made so that power is not supplied to the controller 12, or the original solenoid valve 6, the first solenoid valve 7, and the second solenoid valve 8. May be set so as not to open the valve.

  Further, in order to notify that the temperature sensor 9 is abnormal, the buzzer is generated from the speaker 23, but the notification means is not limited to the generation of the buzzer. For example, the notification may be made by displaying on the display screen 20 that the temperature sensor 9 is abnormal.

  Next, a modified example of the temperature sensor abnormality detection process performed by the CPU 13 after resuming rice cooking after recovery of the power supply voltage (after recovery from a power failure) will be described with reference to the flowchart shown in FIG. In this modified example, if the temperature does not rise for a certain period of time (for example, 1 minute) after the start of cooking rice, the boiling flag is stored in the RAM 15 shown in FIG. 1 as having boiled, and after recovery from a decrease in power supply voltage, When the boiling flag is stored in the RAM 15 (FIG. 9, S6: YES), the determination process of S7 is not performed. Other processes are the same as those in the flowchart shown in FIG. The RAM 15 corresponds to “boiling flag storage means”. By doing in this way, a temperature sensor abnormality detection process can be performed by using a boiling flag.

  The rice cooker of this invention can be utilized for the rice cooker provided with the temperature sensor which detects the temperature of an inner pot.

It is a schematic block diagram of the rice cooker 1. FIG. It is the graph which compared the time-dependent change of the detection temperature which the temperature sensor 9 detects when rice cooking control is performed on various conditions. It is the flowchart of the process at the time of a power failure which the microcomputer 19 at the time of a power failure performs. It is a conceptual diagram which shows supply of the power supply before a power failure (state in which the power supply is normally supplied). It is a conceptual diagram of the process just before a power failure (a state where the voltage from the outlet becomes less than a specified value). It is a conceptual diagram of the process during a power failure. It is a conceptual diagram of the process just before a power failure (a state where the voltage from the outlet becomes less than a specified value). It is a flowchart which shows a temperature sensor abnormality detection process. It is a flowchart which shows the modification of a temperature sensor abnormality detection process.

Explanation of symbols

1 Rice cooker 2 Inner pot 4 Burner 9 Temperature sensor 13 CPU
14 ROM
15 RAM
16 EEPROM
17 Clock IC
19 microcomputer 22 rice cooking button 23 speaker 24 igniter 25 frame rod 40 power supply circuit 41 charging circuit 42 secondary battery t1 first predetermined time t2 second predetermined time P1 first predetermined temperature P2 second predetermined temperature Q0 initial detection temperature Q1 first detection Temperature Q2 Second detection temperature Δγ Predetermined value

Claims (9)

An inner pot for storing the food,
Heating means for heating the inner pot with a flame;
Power supply voltage monitoring means for detecting a power failure or voltage drop;
Timer means for counting the time of power failure or voltage drop;
Flame detecting means for detecting the presence or absence of flame of the heating means;
When the power supply voltage monitoring means detects a power failure or voltage drop, and the flame detection means detects that there is no flame during a power failure or voltage drop within a certain time measured by the timer means, the heating means is re-ignited. Reignition control means for
Temperature detecting means for detecting the temperature of the object to be cooked;
Heating start determining means for determining whether heating by the heating means is started; and
An elapsed time measuring means for measuring an elapsed time from when it is determined by the heating start determining means that heating by the heating means is started;
An initial detection temperature storage means for storing an initial detection temperature that is a temperature detected by the temperature detection means when the heating start determination means determines that heating by the heating means has been started;
First predetermined time determining means for determining whether or not the elapsed time measured by the elapsed time measuring means has reached a first predetermined time;
A first detected temperature memory that stores a first detected temperature that is a temperature detected by the temperature detecting means when the elapsed time is determined to have reached the first predetermined time by the first predetermined time determining means. Means,
When the difference between the initial detection temperature stored in the initial detection temperature storage unit and the first detection temperature stored in the first detection temperature storage unit is equal to or less than a first predetermined value, the temperature detection unit A first abnormality determining means for determining that is abnormal,
When the first detected temperature stored in the first detected temperature storage means is equal to or lower than a second predetermined value, a determination process is performed by the first abnormality determining means, and the first detected temperature is set to the second predetermined value. If it is higher, the determination process by the first abnormality determination unit is not performed. An inner pot for storing the food,
Heating means for heating the inner pot with a flame;
Power supply voltage monitoring means for detecting a power failure or voltage drop;
Timer means for counting the time of power failure or voltage drop;
Flame detecting means for detecting the presence or absence of flame of the heating means;
When the power supply voltage monitoring means detects a power failure or voltage drop, and the flame detection means detects no flame during a power failure or voltage drop within a certain time measured by the timer means, the heating means is re-ignited. Reignition control means for
Temperature detecting means for detecting the temperature of the object to be cooked;
Heating start determining means for determining whether heating by the heating means is started; and
An elapsed time measuring means for measuring an elapsed time from when it is determined by the heating start determining means that heating by the heating means is started;
An initial detection temperature storage means for storing an initial detection temperature that is a temperature detected by the temperature detection means when the heating start determination means determines that heating by the heating means has been started;
First predetermined time determining means for determining whether or not the elapsed time measured by the elapsed time measuring means has reached a first predetermined time;
A first detected temperature memory that stores a first detected temperature that is a temperature detected by the temperature detecting means when the elapsed time is determined to have reached the first predetermined time by the first predetermined time determining means. Means,
When the difference between the initial detection temperature stored in the initial detection temperature storage unit and the first detection temperature stored in the first detection temperature storage unit is equal to or less than a first predetermined value, the temperature detection unit First abnormality determining means for determining that is abnormal,
A boiling flag storage means for storing a boiling flag when the temperature detected by the temperature detection means has not risen for a predetermined period of time that can be determined to be boiling;
When the boiling flag is not stored in the boiling flag storage means, determination processing by the first abnormality determination means is performed, and when the boiling flag is stored in the boiling flag storage means, the first abnormality is performed. The rice cooker characterized by not performing the judgment process by a judgment means.   The first heating stop means for forcibly stopping heating by the heating means when the temperature detection means is determined to be abnormal by the first abnormality determination means. Or the rice cooker of 2.   4. The apparatus according to claim 1, further comprising: a first notification unit that notifies the abnormality of the temperature detection unit when the temperature detection unit is determined to be abnormal by the first abnormality determination unit. The rice cooker in any one of. A heating start instruction means for instructing the heating means to start heating;
And a first instruction invalidating means for invalidating a subsequent heating start instruction by the heating start instructing means when the first abnormality judging means determines that the temperature detecting means is abnormal. The rice cooker according to any one of claims 1 to 4, characterized in that: Second predetermined time determining means for determining whether or not the time measured by the elapsed time measuring means has reached a second predetermined time longer than the first predetermined time;
A second detected temperature storage that stores a second detected temperature that is a temperature detected by the temperature detecting means when the second predetermined time determining means determines that the elapsed time has reached the second predetermined time. Means,
And a second abnormality determining means for determining that the temperature detecting means is abnormal when the second detected temperature stored in the second detected temperature storage means is equal to or lower than a predetermined temperature. The rice cooker according to any one of claims 1 to 5.   The second heating stop means for forcibly stopping heating by the heating means when the second abnormality determining means determines that the temperature detecting means is abnormal. 6. The rice cooker according to 6.   8. The apparatus according to claim 6, further comprising: a second notification unit that notifies the abnormality of the temperature detection unit when the second abnormality determination unit determines that the temperature detection unit is abnormal. Rice cooker as described in. When the second abnormality determining means determines that the temperature detecting means is abnormal, it further comprises second instruction invalidating means for invalidating a subsequent heating start instruction by the heating start instructing means. The rice cooker according to any one of claims 6 to 8, characterized by the following.

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