JPS62286416A - Rice cooker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention Field of Industrial Application The present invention relates to a rice cooker for cooking rice and the like in ordinary households.

BACKGROUND OF THE INVENTION The conventional circuit of this type of rice cooker is as shown in Fig. 4.
Consists of a microcomputer 1 and peripheral circuits.
was. The microcomputer 1 shown here is a CPU
, ROM, RAM, input/output ports, etc., and is a so-called one-chip microcomputer. Reference numeral 2 denotes a bottom temperature sensor attached to the center of the bottom of the bottomed cylindrical container 3 shown in FIG. It is connected to the. As a result, the temperature signal from the bottom temperature sensor 2 is converted into a binary code and read into the microcomputer 1. S is a rice cooking switch, and an input is made to the microcomputer 1 to determine whether or not this rice cooking switch S has been pressed. Reference numeral 6 denotes an AC power source, to which a series circuit consisting of a heater 7 and a relay contact 8 for heating rice, water, etc. contained in the container 3 shown in FIG. The relay contact 8 is opened and closed by causing a current to flow through the relay coil 10 via the transistor 9 in response to a signal from the output port of the relay coil 10 . 11 is a DC power supply for operating the circuit described above.

In the rice cooker configured in this way, the bottom temperature sensor 2 detects the temperature of the water contained in the container 3 together with rice, etc.
When this bottom temperature sensor 2 reaches approximately 90°C, the heater 7
It was common to cook rice porridge by reducing the energization rate to the rice cooker. However, with this configuration, the detection point of the bottom temperature sensor 2 is too low at about 90°C to detect that the water in the container 3 has started boiling. I was now able to cook the rice without bringing it to a boil.

Problems to be Solved by the Invention However, in such a conventional configuration, when the bottom temperature sensor 2 reaches approximately 90'C, the energization rate to the heater 7 is reduced, so that the water in the container 3 is not boiled. There was a problem in that the porridge had to be cooked, and as a result, the porridge was poorly prepared. Also, if you try to reduce the energization rate to the ° heater 7 after boiling the water in the container 3, the detection point of the bottom temperature sensor 2 (approximately 90 °
C) can be made higher, or the energization rate to the heater 7 when the bottom temperature sensor 2 reaches approximately 90°C can be increased slightly compared to the conventional method, but if you do this,
Due to variations in each of the bottom temperature sensor 2, container 3, and heater 7, variations in mutual contact, etc., and changes in the lightning of rice and water in the container 3, the water in the container 3 boils too much and boils over. There was a problem.

The present invention is intended to solve these problems, and aims to provide a rice cooker that can accurately detect the boiling of water in a container and cook rice porridge without boiling over. be.

Means for Solving the Problems In order to solve the above problems, the rice cooker of the present invention includes a bottomed cylindrical container, a heater for heating rice, water, etc. contained in the container, and the container. a lid body that closes the upper opening part of the lid body; a lid temperature sensor installed in the lid body; and a temperature detection means for detecting that the temperature of the lid temperature sensor has become higher than a predetermined temperature. The heater is constructed of an energization rate control means that lowers the energization rate to the heater based on an output, and a control element that controls energization to the heater based on the output of the energization rate control means.

Operation According to the above configuration, when the water in the container is heated by the heater and boils, steam is generated, and this steam hits the lid temperature sensor, and the temperature of the lid temperature sensor rapidly increases. Since the system detects the boiling of water in the container, it is possible to control the power supply to the heater immediately after the water in the container has definitely boiled.As a result, there is no boiling over, and delicious rice porridge can be cooked. In addition, it is possible to provide a safe and easy-to-use rice cooker with a simple configuration.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 to 3. Components in FIGS. 1 to 3 that are the same as those in FIGS. 4 and S shown in the conventional example are designated by the same numbers, and their explanations will be omitted.

FIG. 1 shows a circuit diagram of a rice cooker according to an embodiment of the present invention, which is composed of a microcomputer 1 and peripheral circuits. FIG. 3 shows a partial sectional view of the rice cooker according to the same embodiment, and 12 is a lid body that closes the upper open part of the container 3.

Reference numeral 13 denotes a lid temperature sensor installed in the lid body 12, and the lid temperature sensor 13 has a structure that easily transmits the temperature of the steam when the water contained in the container 3 boils and steam is generated. 14 is an A/D converter.

Next, the operation of the rice cooker configured as above will be explained. FIG. 2 shows a flowchart of a program stored in the ROM in the microcomputer 1, and the operation of the program will be explained according to the steps of the program shown in this flowchart.

First, step 1 determines whether the rice cooking switch 5 has been pressed, and if it has not been pressed, the heater 7
Turn off the power to the rice cooker switch 5 and return to step 1.
When it is determined that has been pressed, the heater 7 starts to be energized in step 3, and the temperature θ of the bottom temperature sensor 2 is changed in step 4.
The process continues until the temperature θ of the bottom temperature sensor 2 becomes higher than 70'C, and the process proceeds to step 6. In this step 5, the operation continues until the temperature φ of the lid temperature sensor 13 becomes higher than 80°C, and when the water contained in the container 3 boils and the steam generated starts to hit the lid temperature sensor 13, the lid temperature When the temperature φ of the sensor 13 rises rapidly and reaches 80'C, the process proceeds to step 6. Step 6 starts counting time To, T, and step 7 determines whether time To exceeds 26 minutes. If time 7 exceeds 26 minutes, proceed to step 2 and count time T.

If it is within 26 minutes, proceed to step 8. In step 8, it is determined whether the time 1 exceeds 6 seconds, and the time T
If 1 is within 5 seconds, the heater 7 is turned on in step 9, and the process proceeds to step 7.

In step 8, if time 1 exceeds 6 seconds, step 1
When the value is 0, the power supply to the heater 7 is stopped, and the process proceeds to step 11.

In step 11, it is determined whether the time 1 exceeds 32 seconds. If the time T1 is within 32 seconds, proceed to step 7; if the time 1 exceeds 32 seconds, step 12
Set the time to 1 to 0 seconds and proceed to Step 7.

In this way, the temperature of the lid temperature sensor 13 increases rapidly due to the steam generated by the boiling of water in the container 3, and the lid temperature sensor 13 detects
Detects that the temperature exceeds 0°C and changes the energization rate to heater 7 to 6
/32 to allow additional cooking for 26 minutes.The water in the container 3 is brought to a boiling point, and then the energization rate to the heater 7 is lowered immediately after that, so there is no boiling over and delicious porridge can be cooked. It can be used to cook rice.

Effects of the Invention As described above, according to the present invention, when water in a container is heated by a heater and boils, steam is generated, and this steam hits the lid temperature sensor, causing the temperature of the lid temperature sensor to rise rapidly. Since boiling of the water in the container is detected by using the Since it is possible to control the power supply to the heater immediately after boiling the rice, it is possible to cook delicious rice porridge without boiling over, and to provide a safe and easy-to-use rice cooker with a simple configuration. It is something.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a rice cooker showing one embodiment of the present invention;
The figure is a flowchart showing an example of the program of the rice cooker, Figure 3 is a side view showing a part of the rice cooker in cross section, and Figure 4 is a flowchart showing an example of the program of the rice cooker.
The figure is a circuit diagram of a conventional rice cooker, and FIG. 6 is a side view showing a part of the rice cooker in cross section. 1...Microcomputer, 2...
Bottom temperature sensor, 6...Rice cooking switch, 7...
...Heater +8...Relay contact, 1o...
...Relay coil, 13...Lid temperature sensor. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure? ---Yakugen is also Tsubu- 5~-Issei Kanyu Mata 6 Tuna? ---j-g8-°゛suL-dedicated k. 10--1・f Ko4rui3-lphantom. Figure 2 Figure 3 3- Volume L 12・- ■ Bath A 3 Figure 4 Figure 5

Claims (1)

[Claims] A cylindrical container with a bottom, a heater that heats rice, water, etc. stored in the container, a lid that closes an open upper part of the container, and a lid temperature sensor installed in the lid. , a temperature detection means for detecting that the lid temperature sensor has become higher than a predetermined temperature; an energization rate control means for lowering the energization rate to the heater based on the output of the temperature detection means; A rice cooker comprising a control element that controls energization to the heater.