JPH04261611A - Rice boiler - Google Patents

Abstract

PURPOSE:To boil rice of selected hardness regardless of the quantity of rice to be boiled. CONSTITUTION:Selecting operation on the quantity of rice to be boiled and a desired hardness of boiled rice is performed. Caloric force and time during boiling rice are controlled with fuzzy inference based on the selecting operation. Different from the previous boiler, there is no need for a user to select the hardness of boiled rice in relation to the quantity of rice to be boiled.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to rice cookers such as gas rice cookers, and more particularly to control during the additional cooking period.

0002

[Prior Art] Fig. 8 is a diagram showing the temperature change in the inner pot of a gas rice cooker during rice cooking. T4 indicates the boiling maintenance period, T4 indicates the additional cooking period, and T5 indicates the unevenness period.

[0003] Generally, the additional cooking period T of conventional gas rice cookers
In No. 4, when one of soft, normal, and hard was selected using the hardness selection switch, the cooking temperature t0 was set according to the selection, and additional cooking was performed at a constant heating power.

0004

[Problem to be Solved by the Invention] In other words, in the additional cooking period T4, the amount of cooked rice is not taken into consideration.
For this reason, even if the same firmness is selected using the firmness selection switch, there is a problem in that the firmness of the cooked rice varies depending on the amount of rice cooked. It was necessary to perform a selection operation using a type selection switch.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a rice cooker that can cook rice to the hardness selected by a hardness selection switch, regardless of the amount of rice to be cooked. purpose.

[0006]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention is constructed as follows.

That is, the present invention provides a rice cooker having a selection operation section that is operated to select the hardness of cooking, and performs fuzzy inference based on the amount of rice cooked and the output of the selection operation section to perform additional cooking. The apparatus is equipped with a fuzzy inference device that outputs the heat power and time of the period, and is configured to control the heat power and time of the additional cooking period based on the output of the fuzzy inference device.

[0008]

[Operation] According to the above configuration, the heat power and time of the additional cooking period are controlled by fuzzy reasoning according to the selection operation of the rice cooking amount and firmness, so that the user does not have to consider the rice cooking amount himself, as in the conventional example. There is no need to make a hard choice.

[0009]

Embodiments Hereinafter, embodiments of the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a gas rice cooker according to an embodiment of the present invention. In the figure, 1 is an inner pot, 2 is a thermistor as a detection element for detecting the temperature of this inner pot 1,
3 is a flame rod that detects the flame, 4 is an ignition transformer for igniting the gas, and 5 to 7 are first units that open and close the gas flow path.
- third valve, and the above configuration is basically the same as that of a conventional gas rice cooker. When the first to third valves 5 to 7 are all open, the thermal power is "high"; when the first valve 5 and the third valve 7 are open, the thermal power is "medium", and the first and second valves 5 , 6 is open, the firepower is "small".

[0011] With this gas rice cooker, the hardness of the cooked rice can be selected not only in the three stages of hard, normal, and soft as in the past, but also in an infinite range.
It is a volume (not shown).

In the gas rice cooker of this embodiment, the additional cooking period is controlled using the control configuration shown in FIG. 2 so that rice can be cooked to the selected hardness regardless of the amount of rice to be cooked.

That is, in the second fuzzy inference section 11,
Based on the rice cooking amount from the first fuzzy inference section 8 and the operation output of the firmness selection volume, fuzzy inference is performed as described later and the heat power and time during the additional cooking period are output to the control section 12. Then, in response to this output, the heating power and time of the additional cooking period are controlled via the above-mentioned valves 5 to 7 and the like.

In the first fuzzy inference section 8, the thermistor 2
The initial temperature of the inner pot 1 detected by the calculation circuit 9
The second fuzzy inference unit 1 performs fuzzy inference based on the membership function and fuzzy rules by inputting the temperature rise rate of the inner pot 1 calculated as described later by
Output the amount of cooked rice to 1. Since the initial temperature of the inner pot 1 before heating starts varies considerably depending on the season, by using this initial temperature as an input variable of the first fuzzy inference section 8,
We are trying to predict the amount of rice cooked more accurately.

The arithmetic circuit 9 of this embodiment calculates the average value of the temperature increase rate at several points by differentially calculating the output of the thermistor 2 at the initial rise in the water absorption period T1 shown in FIG. It is output to the first fuzzy inference section 8.

The configuration and operation of the first fuzzy inference section 8 will be explained.

FIG. 3(A) shows the membership function of the initial temperature of the inner pot 1, which is an input variable of the first fuzzy inference section 8, and has three labels, NB, ZR, and PB. B
) indicates the membership function of the temperature increase rate, which is also an input variable, and has five labels: NB, NS, ZR, PS, and PB.

On the other hand, the amount of cooked rice, which is an output variable, is shown in FIG. 3 (C
), it has five labels, NB, NS, ZR, PS, and PB, and corresponding membership function values.

Then, when the initial temperature and temperature increase rate of the inner pot 1 are given, the fitness of the input variables of each label is calculated in the corresponding fuzzy rule shown in FIG. In each case, the smallest value is selected as the goodness of fit of the input variable (MIN calculation).

Next, each degree of fitness of the input variable in each of the above rules is multiplied by the membership function value of each corresponding output variable label, and the sum of all these multiplication values is the degree of fitness of the input variable. The amount of cooked rice is calculated by dividing by the total value (MAX calculation).

Next, based on the amount of cooked rice from the first fuzzy inference section 8 and the operation output from the firmness selection volume,
The configuration and operation of the second fuzzy inference unit 11 that performs fuzzy inference and outputs the heat power and time of the additional cooking period will be explained.

FIG. 5(A) shows the membership function of the amount of cooked rice, which is an input variable of the second fuzzy inference section 11.
, ZR, and PB, and FIG. 5(B) shows the membership function of the operation output of the hardness selection volume, which is also an input variable, and has three labels, NB, ZR, and PB. ing.

On the other hand, the additional cooking time, which is an output variable, is shown in FIG.
As shown in (A), it has three labels, NB, ZR, and PB, and the corresponding membership function value, and the output variable, firepower, is as shown in FIG. 6(B). , NB, ZR, PB and corresponding membership function values.

Then, when the amount of rice cooked and the output of the hardness selection volume are given, the fitness of the input variables of each label is calculated in the corresponding fuzzy rule shown in FIG. 7(A), and each The smallest value for each rule is selected as the goodness of fit of the input variable (MIN calculation).

Next, each of the fitness degrees of the input variables in each of the above rules is multiplied by the membership function value of each corresponding output variable label in FIG. , the additional cooking time is calculated by dividing by the total value of the suitability of the input variables (MAX calculation).

Similarly, when the amount of rice cooked and the output of the firmness selection volume are given, the fitness of the input variables of each label is calculated in the corresponding fuzzy rule shown in FIG. 7(B). , the smallest value for each rule is selected as the goodness of fit of the input variable (MIN calculation).

Next, each of the fitness degrees of the input variables in each of the above rules is multiplied by the membership function value of each corresponding output variable label in FIG. 6(B), and the sum of all these multiplication values is , is divided by the total value of the suitability of the input variables (MAX calculation), thereby calculating the heat power for the additional cooking period.

The control section 12 controls each section such as the first to third valves 5 to 7 to control the additional cooking period so as to match the time and heat output from the second fuzzy inference section 11.

In this way, the heat power and time of the additional cooking period are controlled by fuzzy inference according to the amount of rice cooked and the operation output of the hardness selection volume, so unlike the conventional example, the user can control the amount of rice cooked by himself/herself. There is no need to select firmness,
Regardless of the amount of rice cooked, it is possible to cook the rice to the selected hardness.

In the above-mentioned embodiment, the amount of rice to be cooked is fuzzy inferred in the first fuzzy inference section 8 based on the initial temperature of the inner pot 1 and the rate of temperature rise. However, as another embodiment of the present invention, During the heating period T2 with high heat, the amount of cooked rice may be determined as in the conventional method.

Further, in the above-described embodiment, the selection of hardness is stepless, but it goes without saying that it does not necessarily have to be stepless.

[0032]

[Effects of the Invention] As described above, according to the present invention, the heat power and time of the additional cooking period are controlled by fuzzy reasoning in accordance with the selection operation of the rice cooking amount and firmness. There is no need to consider the amount of cooked rice and select the firmness.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a gas rice cooker according to an embodiment of the present invention.

FIG. 2 is a block diagram of main parts of the embodiment of FIG. 1;

FIG. 3 is a diagram showing an example of a membership function used in a first fuzzy inference section.

FIG. 4 is a diagram showing an example of fuzzy rules used in a first fuzzy inference section.

FIG. 5 is a diagram illustrating an example of membership functions of input variables of a second fuzzy inference unit.

FIG. 6 is a diagram illustrating an example of a membership function of output variables of a second fuzzy inference unit.

FIG. 7 is a diagram showing an example of fuzzy rules used in a second fuzzy inference section.

FIG. 8 is a diagram showing changes in temperature rise of the inner pot.

[Explanation of symbols]

1 Inner pot 2 Thermistor 8 First fuzzy inference part 9 Arithmetic circuit 11 Second fuzzy inference part

Claims (2)

[Claims] Claim 1: In a rice cooker having a selection operation section operated to select the hardness of cooking, fuzzy inference is performed based on the amount of rice cooked and the output of the selection operation section to determine the heat power during the additional cooking period. A rice cooker comprising a fuzzy inference device that outputs time, and controlling the heat power and time of the additional cooking period based on the output of the fuzzy inference device. 2. The rice cooker according to claim 1, wherein the selection operation section is a volume that allows stepless selection of firmness.