JP3326097B2 - Flame monitoring device and heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame monitoring device and a heating device, and more particularly to a flame monitoring device that prevents unnecessary misfire detection and a heating device that can prevent unnecessary heating stop.

[0002]

2. Description of the Related Art As a heating device, there is a gas rice cooker which is a rice cooker. A gas rice cooker is supplied with gas, which is a medium necessary for combustion, and burns the gas to heat a pot, which is a heated object, to cook rice. The gas rice cooker is provided with a safety mechanism for detecting a misfire and stopping gas supply since a gas leak occurs when a misfire occurs.

[0003] Conventional misfire detection is performed by judging that a misfire has occurred when a temperature detection sensor that measures the temperature of a heated kettle measures a misfire level temperature corresponding to the misfire.

[0004]

By the way, in recent years, with the advance of computerization, switching control of thermal power has been performed by a microcomputer, and the switching operation has tended to be frequently performed in order to cook delicious rice. However, when switching thermal power,
For a moment, a phenomenon occurs in which the supply of gas stops, so that there may be a situation in which there is no flame for a moment. In such a case, if the measurement speed and accuracy of the temperature detection sensor are improved to improve the misfire detection capability, the gas supply will be stopped due to unnecessary misfire detection even though the misfire is not the original misfire. There is a problem that a rice cooking error occurs even though the rice should be cooked by continuing the rice cooking.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flame monitoring device capable of preventing unnecessary misfire detection when the misfire is different from the original misfire. A fourth object of the present invention is to provide a heating device capable of preventing unnecessary misfire detection and preventing unnecessary heating stop.

[0006]

The invention according to claim 1 is a flame monitoring apparatus for monitoring a flame of a heating means for heating an object to be heated, wherein the temperature of the object to be heated by the heating means is monitored. Temperature measuring means for measuring, based on a change pattern of the temperature measured by the temperature measuring means, comprising a flame state determining means for determining whether a state without a flame of the heating means corresponds to misfire, the The flame state judging means is configured to switch the heating power of the heating means based on a temperature change pattern measured by the temperature measuring means after the heating power of the heating means is switched from the first heating power to the second heating power. It is determined whether or not a state without flame corresponds to misfire.

According to this invention, it is possible to determine whether a misfire corresponds to a misfire based on a temperature, that is, a temperature change pattern in consideration of the time measured by the temperature measuring means.

[0008] Then, it can be determined whether or not a state in which there is no flame that can be generated at the time of switching of the thermal power for a moment corresponds to an original misfire.
A second aspect of the present invention is characterized in that the flame state determining means of the first aspect includes a misfire level detecting means, a measuring means, and a determining means. The misfire level detecting means detects that the temperature measuring means has measured the misfire level temperature to be caused by the misfire. The measuring means measures the elapsed time from the detection by the misfire level detecting means. The judging means judges, based on the temperature measured by the temperature measuring means when the measuring means measures the elapse of the predetermined time, whether a state where there is no flame at the time of switching the heating power of the heating means corresponds to a misfire.

According to such an invention, while a misfire is detected by the detection of the misfire level detecting means in the related art, the thermal power is measured based on the temperature of the temperature measuring means when a predetermined time has passed since the detection of the misfire level detecting means. It can be determined that a state where there is no flame at the time of switching corresponds to an original misfire. According to a third aspect of the present invention, when the temperature measured by the temperature measuring means is higher than the misfire level temperature when the measuring means measures the elapse of the predetermined time, It is characterized in that it is determined that a state in which there is no flame at the time of switching the thermal power does not correspond to a misfire.

According to this invention, the same operation as that of the third aspect of the invention can be obtained, and the determination means can be substantially completed by the misfire level detection means.
The invention according to claim 4 is a medium supply means for supplying a medium required for combustion, a heating means for burning a medium supplied by the medium supply means to heat an object to be heated, and the heating means misfiring. And a heating power control means for controlling the heating power of the heating means to be switched from the first heating power to the second heating power. Temperature measurement means for measuring the temperature of the object to be heated by the heating means,
Based on the temperature change pattern measured by the temperature measuring means after the heating power of the heating means is switched from the first heating power to the second heating power by the heating power control means, the flame at the time of switching the heating power of the heating means is determined. And a flame state determining means for determining whether a state where there is no misfire corresponds to a misfire.

According to this invention, the same operation as that of the first invention can be obtained from the viewpoint of misfire determination, and the medium supply stopping means operates in accordance with the misfire determination having such an effect.

[0012]

According to the first aspect of the present invention, no misfire detection is performed at a temperature at a temporary point, and a state without a flame corresponds to an original misfire based on a temperature change pattern defined by a plurality of temperatures. It is possible to prevent unnecessary detection of misfire when the misfire is different from the original misfire. Then, based on the temperature change pattern defined by the temperatures at a plurality of times, it is determined whether or not the state in which the flame generated at the time of switching the thermal power is momentarily absent corresponds to a misfire. Unnecessary misfire detection can be prevented.

According to a second aspect of the present invention, even when a misfire level temperature to be caused by a misfire is measured, a misfire is not detected, and based on the temperature when a predetermined time has elapsed since the measurement of the misfire level temperature, the switching of the thermal power is performed. It is determined whether or not the state without flame corresponds to the original misfire, and it is possible to prevent unnecessary misfire detection when it is different from the original. According to the third aspect of the invention, the same effect as that of the second aspect of the invention can be obtained, and finally, the same misfire level temperature is used as a criterion for determining whether or not a misfire is inherent. Can be simplified.

According to the fourth aspect of the invention, the same effect as the first aspect of the invention can be obtained from the viewpoint of misfire determination. As a result, the supply stop of the medium such as gas accompanying the unnecessary misfire detection is prevented, and the original heating operation as the heating device is not unnecessarily hindered. Therefore, for example, when cooking rice, it is possible to eliminate the erroneous rice cooking error and cook the rice.

[0015]

FIG. 1 is a sectional view of a gas cooker as a heating device according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line XX of FIG. Referring to FIGS. 1 and 2, main body case 2 has a rectangular parallelepiped shape as a whole, and includes a heating chamber 3 having an inner body 30 for accommodating rice cooker 20, a valve device 11 and a control device CP. And a control room 1. And the bottom 3 of the inner trunk 30
1, the burner top 41 of the burner 4 is exposed and the inner body 30 is exposed.
The flange 21 at the upper end of the rice cooker 20 is supported by the peripheral edge of the open portion above. This rice cooker 20 has an inner lid 24.
An outer lid 23 is provided on the outside of the rice cooker 20 and the inner shell 30 so as to be openable and closable.

The main part of the burner 4 is a bottom part 31 of the heating chamber 3.
The burner top 41 is housed in the space below the bottom 31.
Project from the center opening of the lower part of the inner trunk 30. Burner 4
Gas is supplied through a valve device 11 in the control chamber 1, and combustion air is similarly introduced into the control chamber 1, and the space below the bottom 31 of the heating chamber 3 is connected through the communication hole 13. Supplied to

A cord heater 43 is provided on the outer periphery of a cylindrical portion 40 connecting the burner top 41 and the main body below the bottom portion 31 so as to be attached to a donut-shaped support plate 42. The disposition position of the cord heater 43 is set in a donut shape, the inner end thereof substantially coincides with the central opening of the bottom 31, and the outer peripheral end is set outside the body of the inner body 30. .

The burner 4 is a Bunsen burner, which burns with primary air and secondary air supplied from an annular space on the outer periphery of the cylindrical portion 40, and the combustion exhaust gas is converted into an inner body 30 as shown in FIGS. The gap 22 between the rice cooker 20 and the rice cooker 20 rises, and is discharged from below the flange portion 21 to the outside. In this example, the outer lid 23 that is provided so as to cover the upper region of the flange portion 21 and that is located above the heating chamber 3 is supported by the side wall of the main body case 2. The outer lid 23 can be opened and closed from the operation panel 10 provided above the control room 1, and is locked by a detachable locking mechanism R provided on the operation panel 10 in a closed state. I have. An exhaust port 33 is formed at the upper end of the inner trunk 30 at a position corresponding to the fulcrum for opening and closing the outer lid 23 and the side wall excluding the installation part of the lock mechanism R,
The outside of the exhaust port 33 faces a common inner trunk opening 300 provided at the upper end of the main body case 2.

FIG. 3 is an enlarged view showing the vicinity of the temperature detection sensor (hereinafter referred to as a detection sensor) of FIG.
FIG. 4 is an enlarged view of the vicinity of the detection sensor of FIG. 3. A thermocouple-type thermosensitive element is used as the detection sensor S which is a temperature measuring means for measuring the temperature of the cooked rice cooker 20 to be heated and detecting the temperature. This detection sensor S is shown in FIG.
As shown in the figure, the upper end flange portion 35 serving as the upper end surface of the main body case 2 on the side of the heating chamber 3 has a heat-sensitive portion exposed at the upper end surface portion. Therefore, when the rice cooker 20 is accommodated in the inner trunk 30 and the flange portion 21 is supported by the upper end flange portion 35, the flange portion 21 comes into contact with the heat-sensitive portion of the detection sensor S. As a result, the temperature of the flange portion 21 can be detected.

In this example, since it is built in the upper end flange portion 35 above the exhaust port 33, it is designed so that the combustion exhaust gas that has passed through the gap 22 will not heat the detection sensor S. The detection sensor S is, in detail,
As shown in FIG. 4, it is attached to the upper end flange portion 35 of the inner body 30 in a state of being biased by a spring so as to protrude upward. As a result, the flange portion 21 of the rice cooker 20
Is supported by the upper end flange portion 35, the upper end of the detection sensor S is reliably pressed against the lower surface of the flange portion 21 by the urging force of the spring.

FIG. 5 is a schematic block diagram showing an internal configuration necessary for a safety mechanism in the event of a misfire in the gas rice cooker of FIG. 1, and FIG. 6 shows a further internal configuration of the flame state determination unit of FIG. It is the schematic block diagram shown. As shown in FIG.
The burner 4 as a heating means is a rice cooker 2 as an object to be heated.
The heating power is adjusted by the amount of gas supplied by the valve device 11. Valve device 11
Receives a control signal from the thermal power control unit 51 of the control device CP, adjusts the amount of gas supplied to the burner 4, and supplies gas, which is a medium necessary for combustion, as medium supply means.

As described above, the detection sensor S measures the temperature of the rice cooker 20 heated by the burner 4 as a temperature measuring means, and outputs a signal representing the measured temperature to the flame state determination unit 53 of the control device CP. are doing. The flame state determination unit 53 as the flame state determination means determines that the burner 4 is in a state of flame corresponding to misfire based on the temperature measured by the detection sensor S, and indicates that misfire has occurred, and indicates that fact. The misfire detection signal is output to the medium supply stop unit 55. However, when the heating power of the burner 4 is switched from the first heating power to the second heating power, the flame state determination unit 53 receives a signal from the heating power control unit 51 and the detection sensor S after the switching of the heating power measures. Based on the temperature change pattern, it is determined whether or not a state in which there is no instantaneous flame that may occur when switching corresponds to the original misfire, and if it is determined that it does not correspond to the original misfire, the misfire detection signal is turned off. Not output to the unit 55. The detection sensor S
The flame monitoring unit 49 is configured by the flame state determination unit 53.

The medium supply stopping section 55 as a medium supply stopping means receives the misfire detection signal and outputs a stop signal for stopping the supply of the medium gas to the burner 4 to the valve device 11. As shown in FIG. 6, the flame state determination unit 53 includes a misfire level detection unit 57 as a misfire level detection unit, a timer 59 as a measurement unit, and a determination unit 61 as a determination unit.

FIG. 7 shows the flame monitoring unit 4 after the switching of the thermal power of FIG.
9 is a flowchart for explaining the operation of FIG. With reference to FIGS. 6 and 7, an operation of the flame state determination unit 53 will be mainly described. The heating power of the burner 4 is switched to start the process, and as shown in step (represented by ST in the drawing) 201, the misfire level detection unit 57 determines whether or not the detected temperature of the detection sensor S is at the misfire level. That is, when the detection sensor S measures the misfire level temperature corresponding to the misfire that should be caused by the absence of flame due to the momentary gas supply stop when the burner 4 switches the heating power, the misfire level detection unit 57 detects the misfire level. Is detected, and if detected, a detection signal indicating that fact is output to the timer 59. And timer 5
9 starts the measurement as a measuring means for measuring the elapsed time from the misfire level detection as shown in Step 202,
As shown in step 203, a signal indicating that three seconds have elapsed is output to the determination unit 61. Judgment unit 6
1 determines whether or not the measured temperature of the detection sensor S after the elapse of 3 seconds is equal to or lower than the same misfire level temperature as shown in step 204, and a state where there is no flame at the time of switching the thermal power corresponds to the original misfire. Judge. That is, as shown in step 205, when the measured temperature of the detection sensor S after the lapse of 3 seconds is equal to or lower than the misfire level temperature, the determination unit 61 determines whether or not there is no flame when the burner 4 switches the thermal power. Step 2 determines that a flameless state has occurred and that it corresponds to the original misfire.
If the temperature is higher than the misfire level temperature as indicated by reference numeral 06, the state in which there is no flame at the time of switching the thermal power is a momentary moment that occurs at the time of switching the thermal power different from the original misfire. to decide.

As described above, the safety mechanism for stopping the gas supply in the event of a misfire is provided, and even if the thermal power is switched, the misfire level temperature, which is the temporary temperature, is detected as in the prior art. Instead of immediately detecting misfire and detecting misfire, a flame monitoring unit 49 including a flame state determination unit 53 that uses a timer 59 to perform misfire determination in a temperature change pattern taking time into consideration is used. That is, conventionally, when the detection temperature of the detection sensor S reaches the misfire level temperature, it is determined that a misfire has occurred and the misfire is detected, whereas when the thermal power is switched, the misfire level temperature is once detected. After the elapse of the predetermined time, it is determined again whether the detection temperature of the detection sensor S is equal to or lower than the misfire level temperature.

After the end of the misfire determination process, as described above, the determination unit 61 of the flame state determination unit 53 outputs a misfire detection signal to the medium supply stop unit 55 when it determines that a misfire has occurred. The medium supply stop unit 55 outputs a stop signal to the valve device 11 to stop gas supply. In contrast,
When the determination unit 61 of the flame state determination unit 53 determines that a misfire does not occur, the determination unit 61 does not output a misfire detection signal to the medium supply stop unit 55. As a result, there is a state in which there is no flame for a moment when the thermal power is switched. Also, unnecessary fire detection is not performed, and unnecessary thermal power stop is not performed.

FIG. 8 shows data of the temperature measured by the detection sensor S. The vertical axis represents the measurement temperature (unit: mV) of the detection sensor S measured by a thermocouple, and the horizontal axis represents time. The time point A is the time point when the thermal power is switched from small to large, and the time point B is the misfire level temperature of 6 m.
This is the point in time when the voltage has dropped to V, and point C represents the point in time after 3 seconds have passed from point B. As the thermal power was switched from small to large, the gas supply was stopped for a moment and there was no flame, and as a result, the misfire level temperature reached 6 mV. In this case, in the conventional method, it is treated that a misfire has occurred. However, at the time point C, the value is about 8.3 mV, which is larger than the misfire level temperature of 6 mV. Is determined not to be a misfire. On the other hand, if, for example, the misfire level at time C is 6 m
In the case of 3 mV which is equal to or lower than V, there is a state where there is no flame other than when the thermal power is switched, and it is determined that the original misfire has occurred.

Here, the temperature change pattern will be described a little more. A plurality of times (B,
The use of the temperature C) means that a line segment passing through a plurality of time points is defined, and this line segment indicates a change in temperature. Therefore, the presence or absence of a misfire is determined based on the temperature change pattern after the thermal power switching time point A.

It should be noted that the flame state judging section 53 which constitutes the flame monitoring section 49 together with the detection sensor S may be a single apparatus as well as a part of a heating apparatus having a safety mechanism for stopping gas supply. In addition, from the viewpoint of determining the presence or absence of a misfire based on the temperature change pattern, the first misfire level temperature and the second misfire level temperature do not need to be the same level. Since it is considered to drop, the second misfire level temperature is preferably set at a level equal to or lower than the first misfire level temperature. However,
In the case of performing at the same misfire level temperature, the determination unit 61 may be substantially the same as the misfire level detection unit 57, and there is an advantage that the configuration of the flame state determination unit 53 can be simplified.

Further, the point of determining misfire based on the temperature change pattern is not limited to the case of determining whether or not the temperature is the misfire level temperature and further determining whether or not the temperature is the misfire level temperature. A determination may be made as to whether or not a misfire has occurred based on whether or not the temperature when a predetermined time has elapsed after a temperature decrease gradient having a steeper gradient than the descending gradient is obtained is equal to or lower than a misfire level temperature. That is, the processing reference in step 201 of FIG. 7 may be determined based on the temperature drop gradient. In this case, the temperature drop gradient and the misfire level temperature after the lapse of a predetermined time are factors that determine the temperature change pattern.

Further, from the point that misfire is determined based on the temperature change pattern, the temperature gradient when a predetermined time elapses after a temperature drop gradient steeper than the reference temperature drop gradient to be caused by misfire is obtained. The presence or absence of a misfire may be determined. Further, if the first misfire level temperature and the second misfire level temperature after the lapse of a predetermined time are connected by a straight line, misfire is determined based on the temperature gradient.

Further, the above method is effective when the temperature is detected and sampled at the predetermined time (3 seconds) intervals. However, the misfire level is determined based on the temperature change pattern. May be detected, and the subsequent temperature change may be continuously measured. If the temperature continues to decrease, it may be determined that a misfire corresponds, and if there is a temperature rise, it may be determined that a misfire does not correspond. For example, even if continuous measurement is not possible, more detailed sampling is performed for misfire determination, a temperature change pattern that is approximately continuous with the temperature gradient at each time is specified, and the locus of the temperature at each time is drawn as a line. Integrate or determine the temperature change pattern by dividing the temperature change specified by the temperature at each point in time with the area, and determine the misfire based on the difference from the reference temperature change pattern in the case of the original misfire. May go.

Further, the detection sensor as the temperature measuring means is not limited to the thermocouple type, but may be another type of detection sensor, and is not limited to the case of measuring the temperature of the shuttlecock edge. Further, the switching of the thermal power is not limited to large to small, and may be small to large.

Further, the heating device is not limited to a gas cooker, but may be another heating device that supplies a medium necessary for combustion and stops the medium supply when misfire is detected. For example, in addition to a simple gas stove, a gas stove with a rice cooking function having a rice cooking function may be used. Further, time conditions, temperature conditions, and the like are not limited to those described in the embodiments.

FIG. 9 is a first flowchart showing the control of the gas cooker of FIG. 1, FIG. 10 is a second flowchart, and FIG. 11 is a third flowchart. Next, the heating device is not limited to a gas cooker, but the configuration shown in FIGS. 5 and 6 is important when the thermal power is frequently switched and the number of times of switching is large. 9 to FIG.
The control of the gas cooker of FIG. 1 will be described using FIG.

Referring to FIG. 9, when rice cooking is started, in step 101, forced weak combustion is started. The forced weak combustion is continued for one minute as shown in step 102. Then, as shown in step 103,
After one minute, the fire is extinguished. When the switching of the heating power is performed, the configuration shown in FIGS. 5 and 6 operates, and the processing shown in FIG. 7 is performed to determine the misfire. However, in this case, it is determined that the fire has been misfired because the fire has actually been extinguished, and the medium supply stop unit 55 outputs a stop signal to the valve device 11, but the valve device 11 does not supply gas for fire extinguishing. Is processed as it is.

When the thermal power is switched, the above-described misfire determination is performed. Normally, it is determined that no misfire has occurred at the time of the thermal power switching, and regardless of whether the thermal power is switched, When it is determined that a misfire has occurred and the misfire is detected, the gas supply is stopped and a notification of a rice cooking error is displayed. Hereinafter, how the misfire determination is performed by explaining the switching of the thermal power will be described.

Next, as shown in step 104, the fire extinguishing state is continued for one minute, and as shown in step 105, temperature-controlled combustion is set. The temperature control setting here is 45
C., and combustion is continued for 2 minutes as shown in step 106 to maintain 45 C. In addition, since the temperature controlled combustion is performed by switching the thermal power, the misfire determination is also performed in this case. After a lapse of two minutes, a step for discriminating the amount of cooked rice is started in step 107 and subsequent steps. However, if the rice is to be cooked after washing the rice, the process proceeds to step 107. If the rice is cooked immediately after washing the rice, the temperature controlled combustion at 50 ° C. is continued for 12 minutes after step 106, and then the process proceeds to step 107.

Step 107 is a step of forced strong combustion, which is continued for one minute as shown in step 108, and a predetermined amount of heat is given to the rice cooker 20. Then, forced weak combustion is started in step 109, and forced weak combustion is continued for 2 minutes as shown in step 110. Then, in step 111, a predetermined calculation for determining the actual amount of cooked rice is performed based on the temperature measured after the lapse of two minutes. After the calculation is performed to determine the amount of cooked rice, the large, medium, and small branches of the amount of cooked rice are performed in step 112, and if the amount of cooked rice is small, weak combustion is started in step 113, In the case of medium, forced strong combustion is started in step 114, and in the case of large, strong combustion is started in step 117. In the case of weak combustion in step 113, and in the case of strong combustion in step 117, FIG.
As shown in step 118 of 0, weak combustion and strong combustion are continued until the detection temperature (T1) of the detection sensor S reaches 100 ° C. On the other hand, in the case of the forced strong combustion in step 114, after continuing for 2 minutes as shown in step 115, the process is switched to weak combustion in step 116. After switching to weak combustion in step 116, step 1
As in the case of FIG. 13, at step 118 in FIG.
Until the detected temperature (T1) reaches 100 ° C.

Next, in step 119, although not shown, the countdown timer starts operating.
This is because rice cooking is completed after 20 minutes have passed since the detection temperature of the detection sensor S reached 100 ° C (see step 140). In step 120, branching is performed again according to the amount of cooked rice. If the amount of cooked rice is large as shown in step 121, forced strong combustion is started.
As shown in FIG. 2, when the amount of cooked rice is medium or small, forced weak combustion is started. Both the forced strong combustion in step 121 and the forced weak combustion in step 122 are continued for one minute as shown in step 123, and then weakly burns in step 124.

As can be seen from the processing in steps 125 and 126, the weak combustion processing in step 124 is as follows.
The process ends when the detection temperature (T2) of the detection sensor S has reached 108 ° C., or has not reached 108 ° C. but has been continued for 3 minutes. That is, when the detection temperature (T2) of the detection sensor S reaches 108 ° C., the process proceeds from step 125 to step 130, and after 3 minutes, proceeds from step 126 to step 127. Step 127
Is a branching process based on the amount of cooked rice. When the amount of cooked rice is small, the process proceeds to step 129, and the weak combustion is continued. When the amount of cooked rice is large or medium, the process proceeds to step 128, and the combustion is switched to the strong combustion. The reason why the strong combustion was performed when the amount of cooked rice was large or medium in step 127 is that the detection temperature of the detection sensor S did not reach 108 ° C. at the stage of step 127. This is for raising the temperature to 108 ° C. as soon as possible.

Then, the next step 129 is the same processing as step 125, that is, a processing for determining whether or not the detection temperature (T2) of the detection sensor S has reached 108 ° C. In step 129, the detection temperature (T
When 2) reaches 108 ° C., as in step 125,
Proceed to step 130. Step 130 is a branching process based on the amount of cooked rice. If the amount of cooked rice is small, step 1 is performed.
Proceeding to 31, the weak combustion is performed, and if the cooked rice amount is medium or large, proceeding to step 132, the strong combustion is performed. The weak combustion in step 131 and the strong combustion in step 132 are continued until the detection temperature (T3) of the detection sensor S reaches the fire extinguishing temperature as the transition temperature in step 133.

Thereafter, in step 133, when the detection sensor S detects that the extinguishing temperature as the transition temperature has been reached,
In step 134, the valve device 11 controls the gas amount of the burner 4 to completely extinguish the fire, and thereafter, shifts to the spotting process. Note that the two-stage fire extinguishing is performed in step 125, step 129, and step 134 in order to make brown rice and cook delicious rice.

Referring to FIG. 11, the mura process will be briefly described. In step 135, branching is performed based on the amount of cooked rice. If the amount of cooked rice is small, the process proceeds to step 136 and proceeds to step 136.
If the amount of cooked rice is medium, the process proceeds to step 137 to secure a 5 minute unevenness time.
If the amount of cooked rice is large, the process proceeds to step 138, and a three-minute swing time is secured. Step 136, Step 1
37, after step 138, proceed to step 139,
The heater of the lid is turned on, and temperature control heating is performed. This temperature controlled heating is performed until the countdown timer indicates 20 minutes, as shown in step 140. And 20
When the minutes have elapsed, the process proceeds to step 141, where notification of the completion of rice cooking is performed, and the heat retention is started.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a gas rice cooker as a rice cooker according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is an enlarged view of the vicinity of a detection sensor of FIG. 1;

FIG. 4 is a further enlarged view near the detection sensor of FIG. 3;

FIG. 5 is a schematic block diagram showing an internal configuration required for a safety mechanism in the case of a misfire in the gas cooker of FIG.

FIG. 6 is a schematic block diagram illustrating a further internal configuration of the flame state determination unit of FIG. 5;

FIG. 7 is a flowchart for explaining the operation of a flame monitoring unit including the flame state determination unit of FIG. 6;

8 is a graph showing the temperature measured by the detection sensor S of FIG. 6, and is a graph for explaining the operation of the flame state determination unit.

FIG. 9 is a first flowchart showing control of the gas cooker of FIG. 1;

FIG. 10 is a second flowchart showing control of the gas cooker of FIG. 1;

FIG. 11 is a third flowchart showing control of the gas cooker of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 4 ... Burner 11 ... Valve apparatus S ... Detection sensor 49 ... Flame monitoring part 51 ... Thermal power control part 53 ... Flame state determination part 55 ... Medium supply stop part 57 ...・ Misfire level detector 59 ・ ・ ・ Timer 61 ・ ・ ・ Determiner

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Makiko Abe 4-1-2-4, Hirano-cho, Chuo-ku, Osaka-shi Inside Osaka Gas Co., Ltd. (72) Inventor Keiko Aoyagi 4-22-4 Sugamo, Toshima-ku, Tokyo Park・ Nova Sugamo 1103 (72) Inventor Yasuo Koketsu 19-18, Sakuradacho, Atsuta-ku, Nagoya-shi Inside Toho Gas Co., Ltd. Government Masayuki Hasui (56) References JP-A-2-195114 (JP, A) JP-A-2-133544 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23N 5/24 106 A47J 27/00 105 A47J 27/00 109 F24C 3/12

Claims (4)

(57) [Claims] 1. A flame monitoring device for monitoring a flame of a heating means for heating an object to be heated, a temperature measuring means for measuring a temperature of the object to be heated by the heating means, and a temperature measuring means. Flame state determining means for determining whether or not a state in which there is no flame in the heating means corresponds to misfire, based on a temperature change pattern measured by the heating means. Is based on the temperature change pattern measured by the temperature measuring means after the switching from the first heating power to the second heating power, based on the change pattern of the heating means when there is no flame when the heating power is switched corresponds to misfire. Flame monitoring device to determine whether. 2. The misfire level detecting means for detecting that the temperature measuring means has measured a misfire level temperature to be caused by misfiring after the switching of the heating power of the heating means, and the misfire level detecting means. A measuring means for measuring an elapsed time from the detection of the means, and based on a temperature measured by the temperature measuring means when the measuring means measures the elapse of a predetermined time, there is no flame at the time of switching the heating power of the heating means. 2. The flame monitoring device according to claim 1, further comprising: a determination unit configured to determine whether the state corresponds to a misfire. 3. The method according to claim 1, wherein the determining unit is configured to determine whether the heating power of the heating unit is higher when the temperature measured by the temperature measuring unit is higher than the misfire level temperature when the measuring unit measures a predetermined time. The flame monitoring device according to claim 2, wherein it is determined that a state where there is no flame at the time of switching does not correspond to misfire. 4. A medium supply unit for supplying a medium necessary for combustion, a heating unit for burning a medium supplied by the medium supply unit to heat an object to be heated, and in response to misfire of the heating unit. And a heating power control means for controlling a heating power of the heating means to be switched from a first heating power to a second heating power. Temperature measuring means for measuring the temperature of the object to be heated by the heating means; and the temperature after the heating power of the heating means is switched from the first heating power to the second heating power by the heating power control means. A heating device, comprising: a flame state determination unit that determines whether a state in which there is no flame when the heating unit switches the thermal power corresponds to a misfire based on a temperature change pattern measured by the measurement unit.