JP3416543B2 - Flat stove - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat stove for heating a cooking container containing a food to be cooked by a burner.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Unexamined Patent Publication No. Hei 6-319653, there is provided a temperature sensor for detecting the temperature of the cooking container by contacting the bottom surface of the cooking container. It is known that the heating amount of the burner is automatically controlled according to the "temperature".
According to such a stove, as shown in FIG.
The heating amount of the burner is controlled according to the change of (dotted line), and the oil temperature Θ (dotted line) is maintained within a predetermined oil temperature range (hatched zone in the figure). That is, when the sensor temperature T rises to the second control temperature T ₂ (point x), the heating amount of the burner is switched from large to small. Further, when the sensor temperature T drops to the first control temperature T ₁ lower than the second control temperature T ₂ (point x ′), the heating amount of the burner is switched from small to large. Hereinafter, although not shown, the switching of the heating amount of the burner is repeated, and the oil temperature Θ is maintained within the predetermined oil temperature range while rising and falling like the sensor temperature T. The temperature difference between the first control temperature T ₁ and the second control temperature T ₂ is adjusted according to the amount of oil in the cooking container, and the oil temperature Θ
Is maintained within a predetermined oil temperature range.

However, the flat stove, which is one type of stove, has the following disadvantages. The flat stove is one in which a horizontally installed plate is provided with a recess depressed downward, a burner is provided at the bottom of the recess, and a gotoku at the same height as the plate is provided above the burner. In the flat stove having such a configuration, the heat of the burner is likely to be trapped in the recess when the cooking container is placed on the plate. Therefore, as shown in FIG. 9, the sensor temperature T (solid line) is higher than that of an ordinary stove.
Overshoots slightly from the second control temperature T ₂ and slowly decreases. Therefore, when the sensor temperature T drops to the first control temperature T ₁ (point x ″), that is, when the heating amount of the burner is switched from small to large, the oil temperature Θ falls within the predetermined oil temperature range as shown by the solid line. There is the inconvenience of falling off.

The temperature sensor is in contact with the bottom surface of the cooking container, and when a heavy load of food such as frozen croquettes is put into the oil, the temperature of the food product sinks to the bottom of the cooking container, and the oil temperature drops a little. Even if not, the sensor temperature may drop significantly. That is, the correspondence between the actual oil temperature and the sensor temperature may be broken. In FIG. 10, when the heating amount of the burner is small and the sensor temperature T is between T _{1 and} T ₂ (point y), the sensor temperature T in the case where a large load of food is added to oil is input.
And the behavior of oil temperature Θ (both solid lines). When the food is added to the oil, the sensor temperature T decreases faster than usual, and when it decreases to the first control temperature T ₁ (point y ′), the heating amount of the burner is switched from small to large. The sensor temperature T continues to decrease thereafter and then increases, and the second control temperature T ₂
When the temperature rises (point y ″), the heating amount of the burner is switched from a large amount to a small amount. On the other hand, the oil temperature Θ drops sharply when the food is added to the oil, but it is faster than the sensor temperature T. There is an inconvenience that when the sensor temperature T starts to rise and rises to the second control temperature T _2, it exceeds the predetermined oil temperature range and rises.

[0005]

In view of the above background, the present invention can prevent the food or the like in the cooking container from being excessively cooled or heated by automatically controlling the heating amount of the burner. The purpose is to provide a flat stove.

[0006]

In order to solve the above-mentioned problems, a flat stove according to the present invention comprises a horizontally installed plate, a recess recessed downward from the plate, and a cooking container on the recess. Gotoku placed at the same height, a burner provided at the bottom of the recess for heating the cooking vessel placed on the Gotoku, and contacting the bottom surface of the cooking vessel to detect the temperature of the cooking vessel When the temperature detected by the temperature sensor falls below the first control temperature, the heating amount of the burner is switched from small to large, and when the temperature detected by the temperature sensor rises above the second control temperature. In a flat stove equipped with a heating amount control means for switching the heating amount of the burner from large to small, the heating amount control means changes the detection temperature of the temperature sensor each time the heating amount of the burner is switched from large to small. The overshoot amount from the second control temperature for each time is calculated, the first reference temperature lower than the previous second control temperature by a predetermined temperature is calculated, and the next first control temperature is calculated according to the overshoot amount. It is characterized in that the temperature is set higher than one reference temperature.

In the flat stove, how much the sensor temperature becomes higher than the second control temperature at the previous time, that is, the temperature at the time when the heating amount of the burner is switched from large to small immediately before (overshoot amount) is obtained. To be Further, the first reference temperature lower than the previous second control temperature by a predetermined temperature is obtained. Then, the first control temperature for the next time, that is, the temperature at which the heating amount of the burner is switched from small to large immediately after, is set higher than the first reference temperature according to the overshoot amount. That is, when the overshoot amount is 0, the first control temperature for the next time is set equal to the first reference temperature, and is set higher than the first reference temperature as the overshoot amount increases. As a result, it is possible to prevent the time from when the heating amount of the burner is switched from large to small until the sensor temperature decreases to the next first control temperature, substantially extending according to the overshoot amount. You can Then, it is possible to prevent the oil temperature from falling out of the predetermined oil temperature range and decreasing.

When the overshoot amount is 0, the first control temperature for the next time is set equal to the first reference temperature, so that at least the sensor temperature is decreased by a predetermined temperature from the second control temperature at the previous time. During that time, the heating amount of the burner is kept small. Therefore, the predetermined temperature is set so that the heating amount of the burner is kept small to such an extent that the oil temperature does not fall out of the predetermined oil temperature range.

In the flat stove, the heating amount control means obtains the undershoot amount of the temperature detected by the temperature sensor from the previous first control temperature each time the heating amount of the burner is switched from small to large. Further, a second reference temperature that is higher than the previous first control temperature by a predetermined temperature may be obtained, and the next second control temperature may be set lower than the second reference temperature according to the undershoot amount.

In such a flat stove, how much the sensor temperature is lower than the first control temperature at the previous time, that is, the temperature when the heating amount of the burner is switched from small to large immediately before (the amount of undershoot) is obtained. To be Further, the second reference temperature which is higher than the previous first control temperature by a predetermined temperature is obtained. Then, the second control temperature for the next time, that is, the temperature at which the heating amount of the burner is switched from the large amount to the small amount immediately after, is set to be lower than the second reference temperature according to the undershoot amount. That is, when the amount of undershoot is 0, the second control temperature for the next time is set equal to the second reference temperature, and is set to be lower than the second reference temperature as the amount of undershoot increases. As a result, it is possible to avoid that the time from when the heating amount of the burner is switched from small to large until the sensor temperature rises to the second control temperature next time is substantially extended according to the amount of undershoot. You can Then, it is possible to prevent the oil temperature from rising beyond the predetermined oil temperature range.

When the amount of undershoot is 0, the second control temperature for the next time is set equal to the second reference temperature, so that at least until the sensor temperature rises from the previous first control temperature by a predetermined temperature. During that time, the heating amount of the burner is kept large. Therefore, the predetermined temperature is set so that the heating amount of the burner is maintained to a large extent, for example, so that the oil temperature does not rise above the predetermined oil temperature range.

In the flat stove, the heating amount control means sets the second reference temperature to the first first temperature when the detected temperature of the temperature sensor overshoots a set temperature higher than the second control temperature last time. The temperature may be set higher than the control temperature by exceeding the predetermined temperature range.

Here, when the sensor temperature exceeds a preset temperature higher than the second control temperature of the previous time and overshoots, the sensor temperature from the second control temperature of the last time to the first control temperature of the next time is reached. This set temperature is set from the viewpoint that the time may become excessively long. That is, when the sensor temperature greatly exceeds the set temperature and overshoots, the time during which the heating amount of the burner is kept small becomes excessively long, and the oil temperature greatly decreases. In such a case, the time until the sensor temperature reaches the second control temperature from the first control temperature of the next time, that is, the time when the heating amount of the burner is maintained large may be too short. The lowered oil temperature does not rise so much and may not be restored. Therefore, when the sensor temperature overshoots the set temperature, the second reference temperature is set to the first reference value of the previous time.
The temperature is set higher than the control temperature by exceeding a predetermined temperature range. As a result, the second reference temperature is set to a higher temperature than in the normal time when the sensor temperature does not exceed the set temperature, and the second control temperature set based on the second reference temperature is also set to a high temperature. The above situation can be avoided.

In the flat stove, the heating amount control means may set the next second control temperature to be equal to the second reference temperature when the undershoot amount is less than a predetermined amount. When the amount of undershoot is less than the predetermined amount, the oil temperature does not decrease so much from the lower limit of the predetermined oil temperature range. Therefore, in such a case, even if the next second control temperature is not set lower than the second reference temperature,
It is possible to prevent the oil temperature from rising beyond the predetermined oil temperature range due to an excessively long time period during which the heating amount of the burner is maintained large.

When the heating amount of the burner is switched from small to large in a situation where the correspondence between the sensor temperature and the actual oil temperature is broken, the oil temperature rises beyond the predetermined oil temperature range, or conversely the predetermined oil temperature. It may fall outside the temperature range and decrease. Therefore, in the flat stove, by setting an upper limit on the first control temperature and setting a lower limit on the second control temperature, such a situation can be avoided.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a flat stove according to the present invention will be described with reference to the drawings. FIG. 1 is an explanatory configuration diagram of a flat stove according to the present embodiment, FIG. 2 is a flowchart showing a heating amount control method for a burner of the flat stove according to the present embodiment, and FIG. 3 is a characteristic of the flat stove according to the present embodiment. FIG. 4 is an explanatory diagram, and FIG. 4 is a flowchart showing a method for setting the first control temperature of the flat stove according to the present embodiment,
FIG. 5 is an explanatory diagram of a method for setting the first control temperature of the flat stove according to the present embodiment, FIG. 6 is a flowchart showing a method of setting the second control temperature for the flat stove according to the present embodiment, and FIG. It is explanatory drawing of the setting method of the 2nd control temperature of the flat stove of embodiment, and FIG. 8 is a characteristic explanatory view of the flat stove of this embodiment.

As shown in FIG. 1, in the flat stove according to the present embodiment, a horizontally installed plate 1 is depressed downward to form a recess 2 and a burner 3 is provided at the bottom of the recess 2. Above the burner 3 is a Gotoku 6 on which a cooking container 5 containing cooking oil 4 and the like is placed at substantially the same height as the plate 1. Further, a temperature sensor 7 that contacts the bottom surface of the cooking container 5 and detects the temperature of the cooking container 5
And a control unit (heating amount control means) 8 that controls the heating amount of the burner 3 according to the temperature detected by the temperature sensor 7 and performs various controls. Gas is supplied to the burner 3 from a gas supply passage 9, and a spark plug (not shown) is ignited and burned. A gas solenoid valve 10 that is opened and closed by the control unit 8 is provided in the gas supply path 9.
Further, the gas supply passage 9 is provided with a bypass passage 11 that branches in the middle and joins again, and the bypass passage 11 is provided with a bypass solenoid valve 12 that is opened and closed by the control unit 8. By opening and closing the bypass solenoid valve 12, the gas supply amount to the burner 3 is controlled and the heating amount of the burner 3 is switched to a large amount or a small amount.

The control unit 8 has a timer 13, and based on the time measured by the timer 13, 0.5 [s]
Each time, it is determined whether or not the sensor temperature (the temperature detected by the temperature sensor 7) is within the temperature range described below. Further, the control unit 8 is provided with a counter 14, and the counter 1
4 counts the number of times the sensor temperature is continuously determined to be within the temperature range described later.

The control of the heating amount of the burner 3 by the control unit 8 in the flat stove having the above construction will be described. According to the flat stove of the present embodiment, in order to maintain the oil temperature Θ within the predetermined oil temperature range shown by the shaded area in FIG. 3, the burner 3 is detected based on the sensor temperature T according to the flowchart of FIG.
The heating amount of is controlled. When the burner 3 is ignited, the heating amount is increased (STEP 1), and the sensor temperature T and the oil temperature Θ gradually increase as shown in FIG. When the sensor temperature T exceeds a preset control temperature T ₀ (S
YES in TEP2, point B _{0 in} FIG. 3), the heating amount is switched from large to small (STEP 3), the sensor temperature T rises above the control temperature T ₀ and then drops, and the oil temperature Θ also rises slightly. descend.

The sensor temperature T is the first control temperature T ₁ (= T ₀
-2 ° C.) (YES in STEP 4, point A _{1 in} FIG. 3), the heating amount is switched from small to large (STEP
5), the sensor temperature T rises above the temperature T ₀ -2 ° C, and the oil temperature Θ also rises. Further, the sensor temperature T is the second control temperature T
₂ (= T ₀ + 2 ° C) (YE in STEP 6)
S, point B _{1 in} FIG. 3), the heating amount is switched from large to small (STEP 7), the sensor temperature T falls below the temperature T ₀ + 2 ° C., and the oil temperature Θ also falls.

Subsequently, the next first control temperature T ₁ is set according to the amount of overshoot of the sensor temperature T from the previous second control temperature T ₂ (STEP 8). Then, when the sensor temperature T decreases to the first control temperature T ₁ which is sequentially set (points A ₂ , A ₃ , ... In FIG. 3), the heating amount of the burner 3 is switched from small to large (STEP 9). , Sensor temperature T
Rises. Further, the next second control temperature T ₂ is set according to the amount of undershoot of the sensor temperature T from the previous first control temperature T ₁ (STEP 10). When the sensor temperature T rises to the sequentially set second control temperature T ₂ (points B ₂ , B ₃ in FIG. 3), the heating amount is switched from large to small (STEP 11), and the sensor temperature is changed. T decreases. The main feature of the flat stove of the present invention is the setting of the first control temperature T ₁ and the second control temperature T ₂ , which will be described in detail later. Thereafter, STEP 8 to STEP 11 are repeatedly performed, and as shown in FIG. 3, the oil temperature Θ is maintained in the predetermined oil temperature range while the heating amount of the burner 3 changes according to the switching, similarly to the sensor temperature. If the fire extinguishing operation is performed during the combustion of the burner 3, the burner 3 is extinguished at any point in the flowchart shown in FIG.

The setting of the first control temperature T ₁ (STEP 8) and the setting of the second control temperature T ₂ (STEP 10), which are the main features of the flat stove according to the present invention, will be described with reference to FIGS. 4 to 7. . The first of the last time at a certain point
The (second) control temperature means a temperature at which the heating amount of the burner 3 is switched immediately before that time point, and the next first (second) control temperature at a certain time point is immediately after that time point. 3 means the temperature at which the heating amount can be switched.

Next first control temperature T₁Is the sensor temperature T
Is the previous second control temperature T₂How much to rise above
It is set depending on (overshoot amount). Implementation
Since the form represents the amount of overshoot, the sensor temperature T
Is the previous second control temperature T₂From the next first control temperature T₁
MAX temperature T, which is roughly equivalent to the maximum temperature up to_{MA X}
Will be introduced. Hereinafter, as shown in FIG.
Second control temperature T of last time ₂When overshoot from
At the next first control temperature T₁How is set
This will be described with reference to the flowchart of FIG.

First, the second control temperature T of the previous time is set as T _MAX.
2 is set (STEP8-1), and this T _MAX is T ₀ +
It is determined whether or not the temperature is 10 ° C or lower (STEP8-
2). When T _MAX is T ₀ + 10 ° C or less (STEP8-
2 YES), the next first control temperature T ₁ is T _MAX -4 ° C
Is set to be isothermal (STEP8-3). When the amount of overshoot is excessive, that is, T _MAX is T ₀ +
When it is higher than 10 ° C. (NO in STEP8-2), the next first control temperature T ₁ is set to T ₀ + 6 ° C. Therefore, the first control temperature T ₁ for the next time has an upper limit of T ₀ + 6 ° C. The reason why such an upper limit is provided will be described later.

Subsequently, the sensor temperature T continuously increases to T_MAX~ T
_MAXThe counter 14 indicates the number of times in the temperature range of + 10 ° C.
Is counted, and whether or not the number of counts has become 3 or more
Is judged (STEP8-5). Such judgment is made
Depends on whether the sensor temperature T continues to rise.
In other words, if the sensor temperature T has reached its maximum temperature,
This is to judge. The counter 14 counts
The upper limit T of the temperature range of the sensor temperature T_MAXSet + 10 ℃
The key is to exclude the influence of noise from the count number.
It is. As shown in FIG. 5, the sensor temperature T gradually rises.
And the count reaches 3 or more (STEP8-
YES at 5), T_MAXIs the control temperature T₀Lower than + 20 ℃
Is determined (STEP8-6), T_MAXBut
T₀If the temperature is lower than + 20 ° C (YE in STEP8-6)
S), T_MAXThe temperature obtained by adding 1 ° C to_MAXTo be
(STEP8-7). By providing STEP8-6
T _MAXIs T₀With + 20 ° C as the upper limit, as described later, ST
This T in EP10_MAXSecond control for the next time set below
Temperature T₂Also T₀The upper limit is + 20 ° C.
This will be described later.

Thereafter, STEP8-2 to 8-7 are repeated.
Each time, the next first control temperature T ₁Is T₀Above + 6 ° C
In the range that cannot be read, T_MAXTogether with the upward arrow in FIG.
So that the temperature is renewed to 1 ℃ each. The sensor temperature T is
It is near the maximum value and the count number of the counter 14 is less than 3 times
When it becomes (NO in STEP8-5), the next first
Control temperature T₁Is finally set (immediately before STEP8
-3, 4). At this time, the previous second control temperature T₂Than 4
The first reference temperature which is low by ℃ (“predetermined temperature” of the present invention)
(= Last time T₂-4 ° C) is already required (STE
STEP8-3 immediately after P8-1). And next time
1 control temperature T₁Corresponds to the number of upward arrows in FIG.
Overshoot amount (= T_MAX-Previous T₂) According to
It is set higher than the reference temperature.

When the sensor temperature T becomes equal to or lower than the first control temperature T ₁ for the next time (YES in STEP8-8), the control unit 8 switches the heating amount of the burner 3 from small to large (STEP9). The next first control temperature T ₁ is T
It is decided in small increments with _MAX . For this reason, even when the food is put into the oil and the sensor temperature T suddenly changes from rising to lowering, the control unit 8 heats the burner 3 in accordance with the next first control temperature T ₁ set at that time. The amount can be switched from small to large.

Next, the next second control temperature T₂Is the sensor temperature
Degree T is the first control temperature T of the previous time₁How much lower
It is set depending on (undershoot amount). Anda
The sensor temperature T is the first
Temperature T₁From the next second control temperature T₂Until
MIN temperature T roughly corresponding to the minimum temperature shown in_MINIntroduced
To be done. As described above, the previous first control temperature T₁Is
Second control temperature T of last time ₂Depending on the amount of overshoot from
Will be set. Therefore, the cycle of STEP8-11
Second control temperature T in the next₂Undershoot
It is set depending on not only the amount but also the amount of overshoot.
It

As shown in FIG. 7, the sensor temperature T rises to T _MAX, then decreases and undershoots from the first control temperature T _1, and in three cases a, b and c where the undershoot amount at this time is different. How the next second control temperature T ₂ is set will be described with reference to the flowchart of FIG.

First, as T _MIN , the previous first control temperature T
₁ is set (STEP 10-1), and the difference between T _MAX and T _MIN is obtained (STEP 10-2a, 2b). At this time, T _MAX is the previous T ₁ + 4 ° C (STEP8-
3), T _MAX -T _MIN is (previous T ₁ -T _MIN ) + 4 ° C
Can be expressed as Therefore, by _obtaining T _MAX −T _MIN , it is possible to obtain the amount of undershoot of the sensor temperature T from the previous first control temperature T ₁ , that is, the previous T ₁ −T _MIN . When T _MAX -T _MIN is less than 10 ℃ (STEP
10-2a is YES), and the next second control temperature T ₂ is T
It is set to be isothermal with _MAX (STEP 10-3a). T
_{When MAX-} T _MIN is 10 ℃ or more and less than 17 ℃ (STEP
(NO in 10-2a, YES in STEP 10-2b), the second control temperature T ₂ for the next time is set to be 10 ° C. higher than T _MIN (STEP 10-3b). T _{MA X} -T _MIN 1
When the temperature is 7 ° C. or higher (NO in STEPs 10-2a and 10-2b), the next second control temperature T ₂ is T _MAX −T _MIN = 2.
It is set higher than T _MIN by the temperature multiplied by / 3 (S
TEP10-3c).

Next, the next second control temperature T ₂ is T ₀ +
It is determined whether or not the temperature is 2 ° C. or higher (STEP 10-
4). When the temperature is T ₀ + 2 ° C. or higher (YES in STEP 10-4), the next second control temperature T ₂ is not changed, and T ₀ +2
When the temperature is lower than ℃ (NO in STEP 10-4), the next second control temperature T ₂ is updated to T ₀ +2 ℃ (STEP
10-5). Therefore, the second control temperature T ₂ has a lower limit of T ₀ + 2 ° C. The reason why the lower limit is provided will be described later.

Here, the sensor temperature T is continuously T _MIN −
The number of times in the range of 20 ° C. to T _MIN is counted by the counter 14, and it is determined whether or not the number of counts has reached 3 or more (STEP 10-6). This determination is made to determine whether or not the sensor temperature T continues to decrease, in other words, whether or not the sensor temperature T has reached its minimum temperature. The lower limit T _MIN −20 ° C. is provided in the temperature range of the sensor temperature T at which the counter 14 counts,
This is because the influence of noise or the like is removed from the count number.
In the case shown in FIG. 7, the sensor temperature T is T _MIN
When the count value of the counter 14 continues to decrease further and reaches three times or more (YES in STEP 10-6), it is determined whether or not T _MIN is higher than the temperature obtained by subtracting 39 ° C. from the control temperature T ₀ ( (STEP 10-7). T _MIN is T ₀ -3
If the temperature is higher than 9 ° C (YES in STEP 10-7),
The temperature obtained by subtracting 1 ° C from T _MIN is newly set as T _MIN (S
TEP10-8). The reason why STEP 10-7 is provided here is to eliminate the influence of noise or the like from the sensor temperature T.

Thereafter, STEPs 10-2 to 10-8 are repeated, and each time T _MIN is reached as indicated by the downward arrow in FIG.
Is updated to 1 ° C each. Accordingly, in case a,
As shown in b and c, the next second control temperature T ₂ is T _0.
The temperature is gradually updated to a temperature below + 2 ° C. The time during which the sensor temperature T reaches its minimum value and is equal to or lower than T _MIN is short, and the count number of the counter 14 is 3
When it is less than the number of times (NO in STEP 10-4), the next second control temperature T ₂ is finally set (the immediately preceding S
TEP10-3a, 3b, 3c). At this time, normally, the second reference temperature (= T _MAX ) which is higher than the previous first control temperature T ₁ by 4 ° C. (“predetermined temperature” of the present invention) has already been obtained (see STEP 8-3). ). Then, the next second control temperature T ₂ is set to be lower than the second reference temperature according to the amount of undershoot (= previous T ₁ −T _MIN ) corresponding to the number of the downward arrow in FIG. 7.

Here, when the above-mentioned overshoot amount is excessive, that is, when the sensor temperature T is higher than the previous second control temperature T _{2 in} the normal time, T ₀ + 10 ° C. (the “set temperature” of the present invention) Consider the case of overshoot.
In this case, the time until the sensor temperature T drops from the second control temperature T ₂ of the last time to the first control temperature T ₁ of the next time, that is,
The heating time of the burner 3 is kept small for too long, and the oil temperature Θ may fall outside the predetermined oil temperature range and may drop significantly. At this time, even if the second control temperature T ₂ of the next time is set higher than the first control temperature T ₁ of the last time by a predetermined temperature as usual, the sensor temperature T is changed from the first control temperature T ₁ of the previous time to the next temperature of the first control temperature T ₁ of the next time. 2 There is a possibility that the oil temperature Θ will not rise to the predetermined oil temperature range because the time until the temperature rises to the control temperature T ₂ , that is, the time when the heating amount of the burner 3 is kept large is too short.

According to the flat cooktop of the present embodiment, in this case, the STE after the NO determination is made in STEP 8-2.
P8-4 to 8-7 are repeated, and T _MAX is T ₀ + 10 ° C.
It is set to a higher temperature. On the other hand, the first control temperature T ₁ remains at its upper limit T ₀ + 6 ° C. Therefore, in such a case, T _MAX (“second reference temperature” of the present invention) is 4 ° C. (“predetermined temperature range” of the present invention) from the previous first control temperature T ₁ (= T ₀ + 6 ° C.). Is set to a high temperature above (STE
STEP8-7 after going through P8-4). That is, the second reference temperature T _MAX and the next second control temperature T ₂ are set so that the sensor temperature T is higher than the normal temperature (STEP8-
STEP 10-3a-3c after going through 4-8-7). As a result, it is possible to avoid the situation where the heating amount of the burner 3 is kept large as described above and the oil temperature Θ does not rise to the predetermined oil temperature range.

When the sensor temperature T becomes equal to or higher than the next second control temperature T ₂ (YES in STEP 10-7), the control unit 8 switches the heating amount of the burner 3 from large to small (STEP 11). The second control temperature T ₂ for the next time is determined in small increments along with T _MIN . Therefore, even when the sensor temperature T suddenly changes from a decrease to an increase, the control unit 8 switches the heating amount of the burner 3 from large to small according to the second control temperature T ₂ set at that time.

As described above, T ₀ + 6 ° C. is set as the upper limit of the first control temperature T ₁ , and T ₀ is set as the lower limit of the second control temperature T _2.
0 + 2 ° C, and T ₀ + 20 ° C as the upper limit. this is,
This is to prevent the heating amount of the burner 3 from being switched at an inappropriate timing, that is, in a state where the correspondence between the sensor temperature T and the actual oil temperature Θ is broken. Therefore, by setting the upper limit to the first control temperature T ₁ and setting the upper and lower limits to the second control temperature T ₂ , the oil temperature Θ rises above the predetermined oil temperature range,
It is possible to prevent the temperature from falling out of the predetermined oil temperature range. The upper limit of the first control temperature T _{1 and} the upper and lower limits of the second control temperature T ₂ may be changed appropriately according to various conditions.

The first control temperature T ₁ set as described above
A change in the oil temperature Θ when the heating amount of the burner 3 is controlled by the control unit 8 based on the second control temperature T ₂ will be described with reference to FIG. The shaded zone in the figure represents a predetermined oil temperature range in which the oil temperature Θ should be maintained. First, the solid line represents the sensor temperature T and the oil temperature Θ during normal times, that is, when the food is not added to the oil. When the sensor temperature T rises to the previous second control temperature T ₂ (point α), the heating amount of the burner 3 is switched from large to small. Here, as described above, the next first control temperature T ₁ is set to a temperature higher than the first reference temperature (previous T ₂ −4 ° C.) according to the overshoot amount (upward diagonal arrow) (upward white). Arrow). Then, when the sensor temperature T drops to the next first control temperature T ₁ (point α ′), the heating amount of the burner 3 is switched from small to large. By setting the next first control temperature T _{1 in} this way, it is possible to prevent the oil temperature Θ from falling outside the predetermined oil temperature range while the heating amount of the burner 3 is small as shown in FIG. can do.

As described above, if the sensor temperature slightly undershoots from the previous first control temperature T ₁ , the second control temperature T will be equal to the second reference temperature T _MAX.
2 is set. The previous first control temperature T ₁ referred to here is the same temperature that was set as the next first control temperature T ₁ until just before the heating amount of the burner 3 was switched from small to large. . Then, when the sensor temperature rises to the next second control temperature T ₂ (point α ″), the heating amount of the burner 3 is switched from the large amount to the small amount. Thus, the next second control temperature T ₂ is set. By doing so, FIG.
As shown in (3), it is possible to prevent the oil temperature Θ from rising beyond the predetermined oil temperature range while the heating amount of the burner 3 is large.

Next, the sensor temperature when the food is added to the oil
The temperature T and the oil temperature Θ are represented by dotted lines. The heating amount of the burner 3 is small
At this time (point β), if the oil has a large load of croquette, etc.
It is assumed that it was thrown in. The sensor temperature T begins to drop rapidly,
Previous first control temperature T₁When it drops to (point β '),
The heating amount of the speaker 3 is switched from small to large. Where above
The undershoot amount (downward slashed arrow).
Then, the second reference temperature T _MAXSecond control temperature at lower temperature
Degree T₂Is set (downward white arrow). And the sensor
The temperature T is the second control temperature T of the next time.₂When rising to (
β ”), the heating amount of burner 3 is switched from large to small
It Thus, the next second control temperature T₂Is set
Then, as shown in FIG. 8, while the heating amount of the burner 3 is large, the oil
Prevent the temperature Θ from rising beyond the specified oil temperature range
You can

In this embodiment, the next first control temperature T₁Is
T with proportionality coefficient 1_MAXAs set according to the proportional function of
However, as another embodiment, the next first control temperature T₁
Is T _MAXAccording to the increasing function (quadratic function, exponential function, etc.) of
It may be set. As another embodiment
T_MAXWithin the temperature range on the higher temperature side of the multiple temperature ranges
The next first control temperature T₁Is gradually set to high temperature
May be allowed. Also in this case, the sensor temperature T
Second control temperature T of₂The amount of overshoot from
The next first control temperature T₁Is the first reference temperature
Can be set to a high temperature. Therefore, the addition of burner 3
After the amount of heat is switched from large to small, the sensor temperature T
1st control temperature T of times₁It takes too long to decrease below
The oil temperature Θ falls significantly outside the specified oil temperature range.
Can be prevented.

In the present embodiment, the next second control temperature T ₂ is set according to the proportional function of T _MIN of the discontinuous proportional coefficient (0, 1, 1/3), but another embodiment. Alternatively, the next second control temperature T ₂ may be set according to an increasing function (secondary function, exponential function, etc.) of T _MIN . As still another embodiment, the next second control temperature T ₂ may be gradually set to a lower temperature as T _MIN is in the temperature range on the lower temperature side among the plurality of temperature ranges. Further, in the present embodiment, the difference between T _MAX and T _MIN is 10
When the temperature is lower than 0 ° C, the second control temperature T ₂ for the next time is set equal to the second reference temperature (= T _MAX ), but in another embodiment, the difference between T _MAX and T _MIN is _lower than 10 ° C. In some cases, the second control temperature T ₂ for the next time may be set lower than T _MAX according to the amount of undershoot. In the above case, as the amount of undershoot of the sensor temperature T from the previous first control temperature T ₁ increases, the next second control temperature T ₂ can be set lower than the second reference temperature. As a result, the time from when the heating amount of the burner 3 is switched from small to large until the sensor temperature T rises above the second control temperature T ₂ for the next time is too long, and the oil temperature Θ significantly exceeds the predetermined oil temperature range. Can be prevented from rising.

As another embodiment of the present invention, when the correspondence between the sensor temperature and the actual oil temperature is likely to be broken, such as when using a stove with a glass top plate or a stove with a special shape around the sensor. Alternatively, the above-mentioned heating amount control may be performed.

[Brief description of drawings]

FIG. 1 is an explanatory configuration diagram of a flat stove according to the present embodiment.

FIG. 2 is a flowchart showing a heating amount control method for a burner of a flat stove according to the present embodiment.

FIG. 3 is a characteristic explanatory view of the flat stove according to the present embodiment.

FIG. 4 is a flowchart showing a method for setting a first control temperature of the flat stove according to the present embodiment.

FIG. 5 is an explanatory diagram of a method for setting a first control temperature of the flat stove according to the present embodiment.

FIG. 6 is a flowchart showing a method for setting a second control temperature of the flat stove according to the present embodiment.

FIG. 7 is an explanatory diagram of a method for setting a second control temperature of the flat stove according to the present embodiment.

FIG. 8 is a characteristic explanatory view of the flat stove according to the present embodiment.

FIG. 9 is an explanatory diagram showing characteristics of a conventional flat stove.

FIG. 10 is an explanatory diagram showing characteristics of a conventional flat stove.

[Explanation of symbols]

1 ... Plate, 2 ... Recess, 3 ... Burner, 5 ... Cooking container,
6 ... Gotoku, 7 ... Temperature sensor, 8 ... Control unit (heating amount control means)

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-6-123429 (JP, A) JP-A-7-122349 (JP, A) JP-A-63-49634 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F24C 3/12 F24C 7/04 301

Claims (6)

(57) [Claims] 1. A horizontally installed plate, a recess recessed downward from the plate, Gotoku for mounting a cooking container on the recess at the same height as the plate, and a bottom provided in the recess. A burner that heats the cooking container placed on the Gotoku, a temperature sensor that contacts the bottom surface of the cooking container to detect the temperature of the cooking container, and the temperature detected by the temperature sensor is below the first control temperature. And a heating amount control means for switching the heating amount of the burner from small to large and switching the heating amount of the burner from large to small when the temperature detected by the temperature sensor exceeds the second control temperature. In the flat stove, the heating amount control means obtains an overshoot amount of the temperature detected by the temperature sensor from the previous second control temperature every time the heating amount of the burner is switched from a large amount to a small amount. First 2. A flat stove characterized in that a first reference temperature that is lower than the control temperature by a predetermined temperature is obtained, and the next first control temperature is set higher than the first reference temperature according to the overshoot amount. 2. The heating amount control means obtains the undershoot amount of the temperature detected by the temperature sensor from the previous first control temperature each time the heating amount of the burner is switched from small to large, and further 2. The second reference temperature which is higher than the first control temperature by a predetermined temperature, and the next second control temperature is set to be lower than the second reference temperature according to the undershoot amount. Flat stove. 3. The heating amount control means sets the second reference temperature from the previous first control temperature when the detected temperature of the temperature sensor overshoots a set temperature higher than the previous second control temperature. The flat stove according to claim 2, wherein the flat stove is set to a high temperature exceeding the predetermined temperature range. 4. The heating amount control means sets the second control temperature for the next time to be equal to the second reference temperature when the undershoot amount is less than a predetermined amount. The flat stove according to Item 3. 5. The flat stove according to any one of claims 1 to 4, wherein an upper limit is set for the first control temperature. 6. The flat stove according to any one of claims 1 to 5, wherein a lower limit is set for the second control temperature.