JP7208038B2 - Gas stove - Google Patents

Description

The present invention relates to a gas stove provided with a stove burner facing a burner opening formed in a top plate covering the upper surface of a stove body, and heating a cooking vessel placed on a trivet on the top plate by combustion of the stove burner.

Originally, the stove burner was equipped with a thermocouple to detect the flame of the stove burner. Conventionally, there is known a gas stove that detects the occurrence of boiling over from a cooking vessel based on changes in the output (electromotive force) of a thermocouple for flame detection (see, for example, Patent Document 1). That is, when a fire occurs due to boiling over, the output of the thermocouple drops more rapidly than when it blows out, so the occurrence of boiling over is detected based on this phenomenon.

However, in this device, a thermocouple for flame detection is attached only to one position of the stove burner, so if the liquid boiled over is dripped to a position other than the position where the thermocouple is attached, the occurrence of boilover is detected. Can not. Further, even if thermocouples are attached at a plurality of locations around the stove burner, boiling over that does not result in misfire cannot be detected.

JP 2004-108695 A (paragraph 0041)

In view of the above points, an object of the present invention is to provide a gas stove capable of increasing the probability of detecting the occurrence of boilover.

In order to solve the above problems, the present invention includes a stove burner facing a burner opening formed in a top plate covering the top surface of a stove body, and a cooking vessel placed on a trivet on the top plate is burned by the stove burner. In a gas stove adapted for heating, an annular member concentric with the stove burner that is heated by the combustion of the stove burner and that can be cooled by the spilled juices in the event of spillage from the cooking vessel. A plurality of temperature sensors for detecting temperatures at a plurality of locations in the circumferential direction of the object to be measured, and when the degree of decrease in temperature detected by at least one temperature sensor reaches a predetermined degree or more during combustion of the stove burner. Second, it is premised that there is provided a control means for performing at least one of control for judging that boilover has occurred and notifying the occurrence of boilover and control for the stove burner.
The object to be measured can be a burner ring that covers the gap between the burner opening and the stove burner from above.

According to the above premise, if boiled juice drips near any one of a plurality of locations in the circumferential direction of the object to be measured whose temperature is detected by the temperature sensor, the temperature detected by the corresponding temperature sensor decreases. When the degree reaches or exceeds a predetermined degree, it is determined that overcooking has occurred. Therefore, it is possible to increase the probability of detecting the occurrence of boilover, as compared with the case where boilover can be detected only at one point. Furthermore, boilovers that do not lead to misfires can also be detected, and in this respect as well, the probability of detecting the occurrence of boilovers can be increased. Then, when it is determined that boiling over has occurred, the user is notified to that effect to prompt the user to perform an operation to weaken the heating power of the stove burner or to extinguish the fire. By controlling the heating power of the burner to weaken or extinguishing the stove burner, further overcooking can be suppressed.

By the way, when the flame port of the stove burner is blocked by the spilled juice, even if the stove burner is not controlled to extinguish the fire, misfire at the blocked flame port causes the part of the object to be measured corresponding to this flame port to be damaged. The detected temperature of the temperature sensor that detects the temperature of the will not rise. Therefore, the first invention of the present application is based on the above premise, and in which the control over the stove burner is the control for weakening the heating power of the stove burner, the control means detects when it is determined that boiling over has occurred. When the temperature detected by the temperature sensor does not rise even after the elapse of a predetermined period of time after the degree of temperature decrease exceeds a predetermined degree, it is determined that the flame port of the stove burner has been blocked, and the occurrence of the flame port clogging is prevented. It is characterized by performing at least one control of notification control and control of extinguishing the stove burner. According to this, it is possible to ensure safety when the flame port of the stove burner is clogged with the boiled-over juice.

Further, when the stove burner is ignited with the flame port of the stove burner closed, the detected temperature of the temperature sensor for detecting the temperature of the portion of the object to be measured corresponding to the blocked flame port does not rise. Furthermore, when some of the flame ports are blocked, the flames formed in the unclosed flame ports become larger, and the temperature detected by the temperature sensor that detects the temperature of the part of the object to be measured corresponding to this flame port is rises significantly. Therefore, the second invention of the present application is based on the above premise, and in which the control over the stove burner is a control to weaken the heating power of the stove burner or extinguish the stove burner, the control means controls each temperature sensor. A first condition that the difference between the maximum value of the temperature detected until a predetermined time elapses from the start of stove burner ignition and the temperature detected by the temperature sensor at the start of stove burner ignition is greater than or equal to a predetermined lower limit for all temperature sensors. and a second condition that the difference is equal to or less than a predetermined upper limit value for all temperature sensors. When it is determined that both conditions of 2 are not satisfied, it is determined that the clogging of the flame port of the stove burner has occurred, and at least control for notifying the occurrence of the clogging of the flame port and control for extinguishing the stove burner. It is characterized by performing one control. According to this, safety can be ensured when ignition is performed in a state in which the flame port of the stove burner is blocked by the spilled juice.

Here, if the heating power of the stove burner is weak, even if the flame port is not blocked, the maximum value of the temperature detected by the temperature sensor until the predetermined time has elapsed from the time when the stove burner ignition starts and the temperature sensor detects the start of stove burner ignition The difference from the detected temperature at that time may fall below the lower limit. Therefore, when it is determined that the first condition is not satisfied in the ignition determination process, it is determined that the flame port of the stove burner is blocked only when the heating power of the stove burner is equal to or higher than the predetermined heating power. Therefore, it is desirable to perform at least one of control for notifying the occurrence of flame port blockage and control for extinguishing the stove burner. According to this, it is possible to prevent erroneous determination with low heating power.

Also, during a hot restart where the stove burner is extinguished and reignited immediately, the temperature detected by the temperature sensor at the start of the stove burner ignition rises, and even if the flame port is not blocked, the detected temperature rises to the left. do not do. Therefore, the control means performs the ignition timing determination process only when the temperatures detected by all the temperature sensors at the start of stove burner ignition are equal to or lower than the predetermined set temperature, and at least one temperature sensor detects at the start of stove burner ignition. If the detected temperature exceeds the predetermined set temperature, the minimum value of the temperature detected by the temperature sensor until the predetermined time has elapsed from the time the stove burner ignition is started is equal to the temperature detected by the temperature sensor at the time the stove burner ignition is started. The third condition that the temperature is equal to or higher than the temperature, and the difference between the maximum value of the temperature detected by the temperature sensor until a predetermined time has elapsed from the time when the stove burner ignition is started and the temperature detected by the temperature sensor at the time when the stove burner ignition is started. A second ignition timing determination process is performed to determine whether or not a fourth condition of being equal to or less than a second upper limit value is satisfied. When it is determined that the condition is not satisfied, it is determined that the flame port of the stove burner has been blocked, and at least one of control for reporting the occurrence of the flame port blockage and control for extinguishing the stove burner. It is desirable to According to this, erroneous determination at hot restart can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view of the principal part of a gas stove provided with the burner for stoves of embodiment of this invention. The top view of the principal part of the gas stove of embodiment. Sectional drawing cut|disconnected by the III-III line of FIG. FIG. 4 is a flow chart showing the contents of control performed by the control means of the gas stove of the embodiment;

1 to 3, reference numeral 1 denotes a top plate that covers the upper surface of a gas stove main body (not shown). The gas stove is provided with a stove burner 3 facing a burner opening 11 opened in the top plate 1 and heating a cooking vessel such as a pot placed on a trivet 2 on the top plate 1.例文帳に追加The trivet 2 has an annular trivet frame 21 and a plurality of trivet claws 22 fixed to the trivet frame 21 . An annular burner ring 4 concentric with the stove burner 3 is attached to the top plate 1 to cover the gap between the burner opening 11 and the stove burner 3 from above. The burner ring 4 is screwed to a frame 42 arranged on the lower surface of the peripheral edge portion of the burner opening 11 at a projecting portion 41 vertically provided on the lower surface of the burner ring 4, and cannot be removed.

The stove burner 3 includes a burner body 31 inserted through the burner opening 11 and a burner cap 32 on the burner body 31 . The burner body 31 has an inner and outer cylindrical body 311 and an outer cylindrical body 312, and the air-fuel mixture is supplied to the space between the two cylindrical bodies 311 and 312 from a mixing tube portion (not shown). is supplied. The burner cap 32 has an annular shape, and includes a cylindrical portion 321 vertically provided on the inner peripheral portion of the lower surface and fitted to the inner cylindrical body 311 of the burner body 31 , and an outer cylindrical portion 321 vertically provided on the outer peripheral portion of the lower surface of the burner body 31 . and an annular wall 322 that seats on the upper end of body 312 . The annular wall 322 is formed with a plurality of flame ports 33 from which the air-fuel mixture is ejected at intervals in the circumferential direction. A target 323 is protruded from one position around the burner cap 32 . The stove burner 3 is provided with an ignition electrode 34 for sparking with the target 323 and a thermocouple 35 for flame detection.

Referring to FIG. 3, an electromagnetic safety valve 51 and a thermal control valve 52 are interposed in gas supply path 5 to stove burner 3 . Then, when an ignition operation is performed by an ignition operation element (not shown), the electromagnetic safety valve 51 is forcibly opened and the ignition electrode 34 is sparked to ignite the stove burner 3 . Furthermore, by manipulating a heating power adjusting operator (not shown), the heating power adjusting valve 52 is controlled via the controller 6 as control means to adjust the heating power. Further, when a misfire of the stove burner 3 is detected from a change in the output signal of the thermocouple 35 , the controller 6 closes the electromagnetic safety valve 51 to stop gas supply to the stove burner 3 .

Here, the gas stove of this embodiment is configured as follows so as to increase the probability of detecting the occurrence of boiling over. That is, the object to be measured, which is an annular member concentric with the stove burner 3, is heated by the combustion of the stove burner 3 and may be cooled by the spilled juice when the cooking vessel spills over. Three temperature sensors 7 (see FIG. 2) made up of thermistors or the like are provided for detecting temperatures at a plurality of locations, for example, three locations in the circumferential direction of the barrel burner ring 4, and detection signals from these temperature sensors 7 are input to the controller 6. ing.

The controller 6 performs the processing shown in FIG. 4 based on the temperatures detected by the three temperature sensors 7 . This process starts when the ignition of the stove burner 3 is started. First, in STEP 1, whether or not the temperature T0 detected by all the temperature sensors 7 at the start of the stove burner ignition is equal to or lower than a predetermined set temperature YTa. determine whether or not YTa is a temperature for determining whether or not it is a hot restart in which the stove burner 3 is extinguished and immediately reignited, and is set to about 40° C., for example. If the temperature T0 detected by all the temperature sensors 7 at the start of stove burner ignition is equal to or lower than YTa, it is determined that the restart is not hot, and the process proceeds to STEP 2. For example, the difference between the maximum value Tmax of the detected temperature until the lapse of 20 seconds and the detected temperature T0 of the temperature sensor 7 at the start of the stove burner ignition is a predetermined lower limit value α (for example, 3 ° C.) or more is satisfied. If the flame port 33 is not blocked, the temperature detected by the temperature sensor 7 will rise after ignition, so the first condition should be satisfied. Then, if the first condition is satisfied, the process proceeds to STEP4.

Incidentally, if the heating power of the stove burner 3 is weak, even if the flame port 33 is not closed, Tmax-T0<α may occur. Therefore, in order to prevent erroneous determination at low heat power, if the first condition is not satisfied, proceed to STEP 3 and determine whether the heat power of the stove burner 3 is a predetermined heat power (for example, 1700 kcal) or more. do. If the thermal power is less than the predetermined thermal power, the process proceeds to STEP4.

In STEP 4, the maximum value Tmax of the temperature detected by each temperature sensor 7 until a predetermined time (for example, 20 seconds) has elapsed from the start of stove burner ignition and the temperature T0 detected by the temperature sensor 7 at the start of stove burner ignition. It is determined whether or not the second condition that the difference is less than or equal to a predetermined upper limit value β (for example, 15° C.) for all the temperature sensors 7 is satisfied. Here, when some of the flame ports 33 are blocked, the flame formed in the unblocked flame ports 33 becomes larger, and the temperature of the portion of the burner ring 4 corresponding to this flame port 33 is detected. The temperature detected by the sensor 7 rises significantly, and the second condition is no longer satisfied. Therefore, when it is determined in STEP 3 that the thermal power is equal to or higher than the predetermined heating power, or when it is determined in STEP 4 that the second condition is not satisfied, it is determined that the flame port 33 is blocked, and the process proceeds to STEP 5. to close the valve to extinguish the stove burner 3, and then proceed to STEP 6 to perform control to notify the occurrence of flame port blockage by the notification means 8 (see FIG. 3) such as a buzzer, a speaker, and a liquid crystal display. conduct.

If it is determined in STEP1 that the temperature T0 detected by any of the temperature sensors 7 at the start of the stove burner ignition exceeds the predetermined set temperature YTa, it is determined that the hot restart is being performed and the process proceeds to STEP7. During a hot restart, the temperature T0 detected by the temperature sensor 7 at the start of the stove burner ignition rises, and even if the flame port 33 is not blocked, the detected temperature does not rise to the left. Therefore, in STEP 7, the minimum value Tmin of the temperature detected by the temperature sensor 7 until a predetermined time (for example, 20 seconds) has elapsed from the stove burner ignition start time when T0>YTa is the stove burner ignition start time of the temperature sensor 7. A third condition that the detected temperature T0 is equal to or higher than the detected temperature T0, and the temperature sensor 7 where T0>YTa is the maximum detected temperature until a predetermined time (for example, 20 seconds) has elapsed from the start of stove burner ignition. a fourth condition that the difference between the value Tmax and the temperature T0 detected by the temperature sensor 7 at the start of the stove burner ignition is less than or equal to a second upper limit value θ (for example, 10° C.) set relatively small; determine whether it is satisfied. When it is determined that both the third and fourth conditions are not satisfied, it is determined that the flame port 33 is blocked, and the process proceeds to STEPs 5 and 6 to extinguish the stove burner 3 in the same manner as described above; and control for notifying the occurrence of flame port blockage. Since the detected temperature may drop slightly from the start of ignition to the actual ignition, the temperature equivalent to the detected temperature T0 at the start of stove burner ignition under the third condition is a temperature γ slightly below T0 (for example, , 2° C.) at a lower temperature.

When it is determined in STEP 4 that the second condition is satisfied, or when it is determined in STEP 7 that both the third and fourth conditions are satisfied, the process proceeds to STEP 8, where at least one temperature sensor 7 is installed. It is determined whether or not the degree of decrease in the detected temperature of has reached or exceeded a predetermined degree. Specifically, the temperature detected by each temperature sensor 7 is read at regular time intervals (for example, at intervals of 1 second), and the detected temperature T(n) read this time and the detected temperature T(n−1) read last time are and the detected temperature T(n-2) read last time is lower than the detected temperature T(n-3) read before by a predetermined temperature η (for example, 15° C.) or more. If none of the temperature sensors 7 satisfy T(n), T(n-1), T(n-2)≤T(n-3)-η, returning to STEP8 is repeated. On the other hand, when any of the temperature sensors 7 satisfies T(n), T(n-1), T(n-2)≤T(n-3)-η, it is determined that overcooking has occurred. Then, the process proceeds to STE9, in which control is performed to notify the occurrence of boilover by the reporting means 8, and further, in STEP10, control is performed to weaken the heating power of the stove burner 3 by the heating power control valve 52 for the stove burner 3.

According to the above process, if boiled juice drips near any one of the three locations of the burner ring 4 whose temperature is detected by the three temperature sensors 7, the temperature detected by the corresponding temperature sensor 7 is judged to have boiled over when the degree of decrease in the temperature reaches a predetermined degree or more. Therefore, the possibility of detecting the occurrence of boilover is increased compared to the case where boilover can be detected only at one location. Furthermore, since the temperature sensor 7 detects the temperature drop due to the liquid boiled over in the burner ring 4 to detect the boiled over, even the boiled over that does not lead to misfire can be detected. can be done. When it is determined that boiling has occurred, the fact is notified and control is performed to weaken the heating power of the stove burner 3, so that the boiling can be suppressed.

After STEP 10 described above, proceed to STEP 11. In the determination processing in STEP 8, the current temperature sensor 7 for which T(n), T(n-1), T(n-2)≤T(n-3)-η It is determined whether or not the number of times that the read detection temperature T(n) becomes equal to or higher than the previously read detection temperature T(n-1) reaches 3 times. Returning to STEP12 is repeated until it is determined that a predetermined time ts (for example, 10 seconds) has elapsed. When the number of times T(n)≧T(n−1) is reached three times before the predetermined time ts elapses, it is determined that the boilover has been eliminated, and the process proceeds to STEP 13 to notify the occurrence of the boilover. is stopped and the heating power of the stove burner 3 is restored, and then the process returns to STEP8.

Here, when the flame port 33 of the stove burner 3 is blocked by the spilled juice, even if the stove burner 3 is not extinguished, misfire at the blocked flame port 33 would normally cause this flame. The portion of the burner ring 4 heated by the flame formed in the mouth 33 is no longer heated, and the temperature detected by the corresponding temperature sensor 7 is no longer increased. Therefore, when the number of times T(n)≧T(n−1) does not reach three times before the predetermined time ts elapses, that is, in the determination processing in STEP 8, T(n), T(n−1), When the temperature detected by the temperature sensor 7 does not rise even after the lapse of a predetermined time ts after T(n-2)≤T(n-3)-η, the clogging of the flame port 33 of the stove burner 3 has occurred. Then, it proceeds to STEP 5 and STEP 6, and performs control to extinguish the stove burner 3 and control to report the occurrence of clogging of the flame port in the same manner as described above.

In some gas stoves, the electromagnetic safety valve 51 is kept open by the electromotive force of the flame detection thermocouple 35 of the stove burner 3, and the thermal control valve 52 is manually operated. With this device, the controller 6 cannot close the electromagnetic safety valve 51 or adjust the thermal power through the thermal power control valve 52 . Therefore, in this case, STEP 5 and STEP 10 are omitted, and if it is determined in STEP 3 that the thermal power is equal to or higher than the predetermined thermal power, or if it is determined that the second condition is not satisfied in STEP 4, or if STEP 7 determines that the third and fourth If it is determined that both conditions are not satisfied, or if it is determined that the predetermined time ts has passed in STEP 12, proceed to STEP 6, perform control to notify the occurrence of flame port blockage, and then proceed to STEP 8. , T(n), T(n−1), T(n−2)≦T(n−3)−η in STEP 8, and when it is determined that boilover has occurred, boilover occurs in STEP 9. After performing control to report the occurrence of , the process proceeds to STEP11.

Although the embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited thereto. For example, in the above-described embodiment, the temperature is detected at a plurality of points in the circumferential direction of the burner ring 4, but it is also possible to detect the temperature at a plurality of points in the circumferential direction using the burner cap 32 as the object to be measured. Further, STEP3 may be omitted, and when it is determined in STEP2 that the first condition (Tmax-T0≧α) is not satisfied, the process may proceed to STEP5.

DESCRIPTION OF SYMBOLS 1... Top plate 11... Burner opening 2... Trivet 3... Stove burner 33... Flame port 4... Burner ring (object to be measured) 6... Controller (control means) 7... Temperature sensor.

Claims (5)

A gas stove equipped with a stove burner facing a burner opening opened in a top plate covering the top surface of a stove body, and heating a cooking vessel placed on a trivet on the top plate by combustion of the stove burner,
The object to be measured is an annular member concentric with the stove burner, which is heated by the combustion of the stove burner and may be cooled by the spilled juice when boiling occurs from the cooking vessel. a plurality of temperature sensors for detecting temperatures at a plurality of locations in the circumferential direction of the
control for judging that boilover has occurred and reporting the occurrence of boilover when a degree of decrease in temperature detected by at least one temperature sensor reaches or exceeds a predetermined degree during combustion of the stove burner; and a control means for performing at least one control of control over the stove burner is control to weaken the heating power of the stove burner ,
When the temperature detected by the temperature sensor has decreased to a predetermined degree or more when it is determined that boiling over has occurred, and the temperature detected by the temperature sensor does not rise even after a predetermined time has passed, the control means closes the flame port of the stove burner. A gas stove characterized by performing at least one of control for notifying occurrence of clogging of a flame port and control for extinguishing a stove burner by judging that clogging has occurred . A gas stove equipped with a stove burner facing a burner opening opened in a top plate covering the top surface of a stove body, and heating a cooking vessel placed on a trivet on the top plate by combustion of the stove burner,
The object to be measured is an annular member concentric with the stove burner, which is heated by the combustion of the stove burner and may be cooled by the spilled juice when boiling occurs from the cooking vessel. a plurality of temperature sensors for detecting temperatures at a plurality of locations in the circumferential direction of the
control for judging that boilover has occurred and reporting the occurrence of boilover when a degree of decrease in temperature detected by at least one temperature sensor reaches or exceeds a predetermined degree during combustion of the stove burner; and control means for performing at least one of control over the stove burner, the control over the stove burner is control to weaken the heating power of the stove burner or extinguish the stove burner,
The control means is configured so that the difference between the maximum value of the temperature detected by each temperature sensor until a predetermined time elapses from the start of ignition of the stove burner and the temperature detected by the temperature sensor at the start of ignition of the stove burner is set to a predetermined value by all the temperature sensors. An ignition time determination process is performed to determine whether or not a first condition that the difference is equal to or greater than the lower limit value and a second condition that the difference is equal to or less than a predetermined upper limit value for all the temperature sensors are satisfied. When it is determined that both the first and second conditions are not satisfied in the time determination process, it is determined that the flame port of the stove burner has been blocked, and control to notify the occurrence of the flame port blockage; A gas stove characterized by performing at least one control of extinguishing a burner. When it is determined that the first condition is not satisfied in the ignition time determination process, it is determined that the flame port of the stove burner is blocked only when the heating power of the stove burner is equal to or higher than a predetermined heating power, 3. The gas stove according to claim 2 , wherein at least one of control for notifying occurrence of clogging of flame port and control for extinguishing the stove burner is performed. The control means performs ignition timing determination processing only when the temperatures detected by all the temperature sensors at the start of stove burner ignition are equal to or lower than a predetermined set temperature, and the detection by at least one temperature sensor at the start of stove burner ignition is performed. If the temperature exceeds the predetermined set temperature, the minimum value of the temperature detected by the temperature sensor until the predetermined time has elapsed from the time the stove burner ignition is started is equal to or higher than the temperature detected by the temperature sensor at the time the stove burner ignition is started. and the difference between the maximum value of the temperature detected by the temperature sensor until a predetermined time elapses from the time when the stove burner ignition is started and the temperature detected by the temperature sensor at the time when the stove burner ignition is started is a predetermined A second ignition timing determination process is performed to determine whether or not a fourth condition of being equal to or less than the second upper limit value is satisfied, and both the third and fourth conditions are determined in the second ignition timing determination process. When it is determined that the conditions are not satisfied, it is determined that the flame port of the stove burner has been blocked, and at least one of control for notifying the occurrence of the flame port blockage and control for extinguishing the stove burner is performed. 4. The gas stove according to claim 2 or 3 , characterized in that: The gas stove according to any one of claims 1 to 4 , wherein the object to be measured is a burner ring covering a gap between the burner opening and the stove burner from above.

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