JPH0796926B2 - Gas stove temperature control device - Google Patents

Description

Description: <Industrial field of application> The present invention relates to an improvement of a gas stove temperature control device for maintaining a pot temperature at a desired set temperature.

<Prior Art> A gas stove such as a table stove is known in which the temperature of the pot can be maintained at a desired set temperature. The general configuration includes a burner thermal power switching means, a temperature setting means, a temperature detecting means, a controlling means, etc., and sets and detects a first reference temperature and a second reference temperature slightly lower than the first reference temperature. When the temperature of the pot rises above the first reference temperature, the burner is set to a small fire, and when it falls below the second reference temperature, it is set to a large fire. As the temperature detecting means,
For example, a structure in which a sensor with a built-in thermistor is applied to the pan bottom is used.

FIG. 5 (a) exemplifies a change in temperature due to this operation. T ₁ is the first reference temperature, T ₂ is the second reference temperature, the burner repeats large and small fires, and the temperature of the pot slightly exceeds the reference temperatures T ₁ and T ₂ with this. It is maintained within this range while fluctuating up and down.

<Problems to be Solved by the Invention> The temperature of the pot detected by the sensor rises slightly later than the portion of the burner where the flame of the burner is directly hit due to a delay in heat conduction of the pot material. For this reason, when heating with a large fire and the detected temperature reaches the reference temperature T ₁ , the temperature of the part where the flame is hit is considerably higher than T ₁ , and at that point the heating power switches to a small fire. However, as shown by F in FIG. 5 (b), the actual pot temperature greatly exceeds T ₁ . For this reason, the temperature of the non-cooked food in the pan also fluctuates greatly,
In particular, tempura oil, which has a delicate influence on the finish of cooking, may give unfavorable results.

The present invention has been made in view of these problems, and has been made for the purpose of preventing an overshoot of the temperature of the pot.

<Means for Solving the Problems> In order to achieve the above-mentioned object, in the present invention, switching means for switching the heating power of the burner, temperature setting means for setting the operating point of the switching means, and the temperature of the pot are detected. And a control means for controlling the switching means according to the set operating point and the detected pot temperature,
As the operating point, the first and second reference temperatures are set as in the conventional case and the switching means is controlled so as to maintain the desired set temperature, and the third reference temperature is slightly lower than the second reference temperature.
When the temperature of the pan is detected to have reached the third reference temperature when the reference temperature is set and the burner is heated to a high temperature at a temperature lower than the third reference temperature, the burner is turned down. The switching means is controlled so that the burner is set to fire again when the temperature of the pot does not exceed the first reference temperature after a certain period of time.

FIG. 1 is a diagram showing the configuration of the present invention, in which A is a thermal power switching means, B is a temperature setting means, C is a temperature detecting means, and D is a controlling means.

<Operation> When the temperature of the pot reaches the third reference temperature, the heat becomes small and the temperature rises gradually. For this reason, even if the fire becomes large again after a certain period of time, the temperature does not rise at a rising rate that greatly exceeds the first reference temperature, and overshoot is prevented.

<Example> Next, one example shown in the drawings will be described. FIG. 2 is a block diagram, FIG. 3 is a control flowchart, and FIG. 4 is a diagram showing a temperature change state and a thermal power switching state.

In FIG. 2, 1 is a gas inlet, 2 is a device plug provided with a safety valve 2a and a manual adjustment valve 2b, 3 is a thermal power switching valve, 4 is a bypass, 5 is a burner, and gas is from the gas inlet 1 to each valve. After being supplied to the burner 5, the amount of supply is continuously adjusted by the manual adjusting valve 2b, and when the thermal power switching valve 3 is opened, it is adjusted to two stages of large fire and small fire by closing. 11 is a microcomputer, 12 is an operating unit, 13 is a temperature sensor, 14 is a thermal power switching circuit, 15 is a safety valve drive circuit, 16 is a display unit, and 17 is a power supply unit. The operation unit 12 is appropriately provided with input keys for inputting temperature and other setting contents, and the microcomputer 11 is operated according to the setting contents to control each unit. The thermal power switching valve 3 is opened and closed by the thermal power switching circuit 14, and the safety valve 2a is operated by the safety valve drive circuit 15.
Driven by.

Since such a hardware configuration itself is basically the same as a conventionally known one, detailed description thereof will be omitted, and the control procedure according to the present invention will be described next with reference to FIG.

First, when the instrument plug 2 is opened, the thermal power switching valve 3 is opened, and the burner is ignited in the state of a large fire (step S1). When combustion starts, the state of the check flag is confirmed (step S).
2). Since the check flag is reset at first, the process proceeds to step S3, the temperature of the pan bottom is detected by the temperature sensor 13, and this loop is repeated until the _third reference temperature T3 is reached. Step S4 becomes on the detected temperature T _3, the amount of gas-fired switching valve 3 is in the closed is in a state of small fire decreases the amount regulated by the bypass 4. Then, this state is maintained for a preset time, for example, 10 seconds, and when the time elapses, the process proceeds to step S5. In this step, it is determined whether or not the detected temperature is equal to or higher than the first reference temperature T ₁ , and if it is above, it remains small fire, and if it is not above, the thermal power switching valve 3 is opened to make it a large fire state. , Set the check flag and return to step S2.

This time the check flag is set the procedure proceeds to step S6, if the detected temperature is above T ₁ and the thermal switching valve 3 remains closed, the flow proceeds to step S7 unless above T _1. Step S7 is to open the thermal power switching valve 3 if the detected temperature is T ₂ or lower, and to keep the thermal power switching valve 3 as it is if the temperature is not lower than T _{2. In} this case, the thermal power switching valve 3 is turned on in Step S5. Since it is open, the state of high fire continues.

After that, the loop for returning from step S6 and step 7 to step S2 is repeated, and when the detected temperature rises above T _1, it becomes a small fire, and when it falls below T ₂ it becomes a big fire, as shown in (a) of FIG. This is normal control, and the detected temperature is maintained within the range of the reference temperatures T ₁ and T ₂ .

The temperature change and the thermal power state in the above control are as shown in FIG. That is, (a) shows that when the detected temperature does not reach T ₂ after the elapse of the certain time in step S4,
(B) shows the case between T ₁ and T ₂ , and (c) shows the case where it is more than T ₁ .

In addition, since the heat capacity varies depending on the size and material of the pot, the type and amount of cooking material in the pot, and the influence of convection, the rate of change of the temperature of the pot varies even with the same heating power. Therefore, each reference temperature must be properly selected so that good control can be performed.For example, confirm standard values by experiments and create a manual, etc., and select the reference temperature accordingly. It is desirable to do.

In addition, the embodiment is an example in which the burner is ignited to start cooking, but after reaching a desired set temperature, for example, oil is replenished, or a large amount of an object to be cooked is added to control the temperature. Even in the case where the temperature is lowered and the temperature is reheated, the same control can be performed by using the third reference temperature by slightly modifying the procedure.

<Effects of the Invention> As is apparent from the above-described embodiment, the present invention has the third reference temperature slightly lower than the second reference temperature in addition to the first and second reference temperatures for setting the target temperature. Was set, and when the temperature rises from a low temperature to a large fire and reaches the third reference temperature, it becomes a small fire, and when the temperature of the pot does not rise above the first reference temperature after a certain period of time, it becomes a large fire again. It is a thing.

Therefore, the temperature rise after reaching the third reference temperature becomes gradual, and the overshoot that greatly exceeds the first reference temperature is prevented. When the temperature reaches the set temperature, the temperature becomes stable, and a good cooking result can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing the configuration of the present invention, FIG. 2 is a block diagram of an embodiment, FIG. 3 is a control flowchart, FIG. 4 is a diagram showing temperature changes and thermal power states, and FIG. It is a figure which shows the temperature change of an example, and the state of thermal power. 3 ... Thermal power switching valve, 4 ... Bypass, 5 ... Burner, 11
...... Microcomputer, 12 ...... Operation part, 13 ...... Temperature sensor, 14 ...... Fire power switching circuit, T ₁ ...... First reference temperature,
T ₂ ...... Second reference temperature, T ₃ ...... Third reference temperature.

Claims (1)

[Claims] 1. A switching means for switching the burner heating power, an operating point of the switching means, a first reference temperature, a second reference temperature slightly lower than this, and a third reference temperature slightly lower than this second reference temperature. Temperature setting means for setting the reference temperature of
Depending on the detection means for detecting the temperature of the pan and the set operating point and the detected temperature of the pan, when the temperature of the pan rises above the first reference temperature, the burner is set to a low heat and the second reference temperature is reached. When the temperature falls below the above, the switching means is controlled so as to maintain a desired set temperature by setting a high fire, and
When the burner is heated to a high temperature at a temperature lower than the reference temperature, the burner is set to a low heat when it is detected that the temperature of the pan reaches the third reference temperature, and the temperature of the pan is reached after a certain period of time. And a control means for controlling the switching means so that the burner becomes a high fire again when the temperature does not exceed the first reference temperature.