JPH03212225A - Electric rice cooker - Google Patents

Abstract

PURPOSE:To prevent dew condensation on the inner side of a lid at the upper part of a vessel, and keep thermal insulation for cooked rice without any deterioration thereof in taste, form or the like by controlling bottom, barrel and lid heaters in such a way that power supply thereto is kept at a specified rate or interrupted for keeping the predetermined thermal insulation temperature when an output signal from a temperature detection means drops to or below the level of the aforesaid temperature. CONSTITUTION:A control means 27, upon receipt of a signal from a temperature detection means 26, supplies electric power to a lid heater 25 and a barrel heater 24 at a specified rate, during the time of a thermal insulation process start immediately after a cooking process to the drop of an output signal from the aforesaid means 26 to or below the predetermined thermal insulation temperature. In addition, the control means 27 controls a bottom heater 23, the barrel heater 24 and the lid heater 25 respectively for power supply thereto at a specified rate, or for the interruption of power supply thereto so as to keep the thermal insulation temperature at the predetermined level, when an output signal from the aforesaid means 26 drops to or below the aforesaid level. According to the aforesaid construction, dew condensation in a vessel 21 is prevented, and the taste, form or the like of cooked rice is free from deterioration without any dew drop falling on the cooked rice.

Description

[Detailed description of the invention] Industrial applications 2 pages The present invention relates to an electric rice cooker having a heat retention function.

BACKGROUND OF THE INVENTION In recent years, electric rice cookers with a heat-retaining function are required not only to cook rice well, but also to have a heat-retaining function that is delicious and keeps the rice hot.

A conventional electric rice cooker of this type will be explained with reference to FIGS. 4 and 6.

As shown in FIG. 4, there is a container 2 with a lid 1 on the top to hold rice and water, and a bottom heater 3 that heats the bottom of the container 2.
, a body heater 4 that heats the side portion of the container 2, and a
The thermistor 5 detects the temperature of the container 2, and the signal from the thermistor 6 is input, and the temperature of the container 2 detected by the thermistor 5 reaches the specified temperature immediately after the rice cooking process enters the warming process. Page 3 of the device is constructed of a control circuit board 6 that controls the bottom heater 3 and the body heater 4 to respectively energize at a constant energization rate or to stop energizing. The operation of the rice cooker will be explained with reference to the flowchart in FIG.

In FIG. 6, a rice cooking process is performed in step 1o. In step 11, it is determined whether the rice cooking process has been completed, and if the rice cooking has not been completed, the process returns to step 1o.
Repeat steps 10 to 11 until the rice is cooked.

When the rice cooking is finished, proceed to step 12 and check the thermistor 6.
Enter the temperature of container 2 using . Next, in step 13, if the temperature has not reached the keeping temperature (71.5°C), in step 14, the body heater 4 is turned on at 1 s/16, and the bottom heater 3 is turned on at 1 s/16.
Electricity is applied at an energization rate of /16, and if the temperature exceeds the heat retention temperature, the electricity supply to the body heater 4 and the bottom heater 3 is stopped in step 15.

After executing steps 14 and 16, the process returns to step 12. Steps 12 to 15 were repeated to control the temperature of the container 2 to the keeping temperature, and the rice in the container 2 was kept warm.

Problems to be Solved by the Invention In such conventional electric rice cookers, when the lid is opened and then closed again while the rice is being kept warm, the lid is cold, so dew forms on the inside of the lid, and the dew forms on the rice. There was a problem with the rice falling onto the top and retaining moisture, causing it to lose its shape and turn white.

The present invention solves the above problems by preventing dew from forming on the inside of the lid at the top of the container, and improving the taste of rice due to the adhesion of dew.
The purpose is to retain heat without deteriorating its shape.

Means for Solving the Problems In order to achieve the above objects, the present invention provides a container with a lid on the top for storing rice and water, a bottom heater for heating the bottom part of the container, and a side part of the container. A body heater that heats the
It includes a lid heater that heats the inside of the lid of the container, a temperature detection device that detects the temperature of the container, and a control device that inputs a signal from the temperature detection device, and the control device controls the process from the rice cooking process to the warming process. The lid heater and the body heater are energized at a constant energization rate for a period from immediately after the temperature detection means reaches the specified heat retention temperature until the output of the temperature detection means becomes equal to or lower than the specified heat retention temperature. Hereinafter, as a means to solve the problem, the bottom heater, the body heater, and the lid heater are controlled to be energized at a constant energization rate or to stop energization so that the temperature is maintained when the temperature becomes below 5. There is.

Effects of the present invention With the above-described configuration, after the rice cooking process moves to the heat-retaining process, electricity is supplied to the open-lid heater and the bottom heater until the temperature of the container falls below the specified heat-retaining temperature, thereby reducing the temperature inside the lid. This prevents the lid from falling down and prevents dew from forming on the inside of the lid. Furthermore, when the temperature of the container falls below the heat retention temperature, the body cover, bottom heater, and lid heater are controlled to maintain the bottom temperature at a constant heat retention temperature and prevent dew from forming inside the container.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIGS. 1, 2, and 3.

As shown in the figure, a container 21 has a lid 22 on the top and contains rice and water. The bottom part of this container 21 is heated by the bottom heater 23, and the side part is heated by the body heater 246. The lid heater 25 heats the inside of the lid 22. The temperature detection means 26 detects the temperature of the container 21. The control means 27 inputs the signal from the temperature detection means 26 and keeps the lid heater 26 and the body heater 24 constant for a period from immediately after the rice cooking process to the heat retention process until the temperature detection means 26 becomes below the specified heat retention temperature. The temperature detection means 2 is energized with a current conduction rate of
The bottom heater 23, the body heater 24, and the lid heater 26 are connected to the bottom heater 23, the body heater 24, and the lid heater 26 so that the heat retention temperature is reached when the output of
and are controlled to be energized at a constant energization rate or to stop energization.

Next, FIG. 2 is a specific circuit diagram, in which a start key 28 is used to start the rice cooking process, and a cancel key 29 is used to cancel the rice cooking process and the warming process.

A temperature detection sensor (hereinafter referred to as a thermistor) 26 is connected to the container 2
1 is detected and inputted to the A/D converter 3o, and this A/D converter 3o is
The /D converter 3o performs A/D conversion on the signal from the thermistor 26. The relay 31 is for energizing the bottom heater 23, and has a relay coil 31a and a relay contact 31b. The relay 7 page drive section 32 drives the relay 31.

The relay 33 is only for energizing the body heater 24.
It has a relay coil /l/ 33a and a relay contact 33b. The relay drive section 34 drives the relay 33. The relay 36 is for energizing the lid heater 25, and has a relay coil/1z35a and a relay contact 35b. The relay drive section 36 drives the relay 36. The input section 37 has a start key 28 and a cancel key 2.
9 and the A/D converter 30 are input. The output section 38 outputs relay opening/closing signals to each of the relay drive sections 32, 34, and 36. The control section 39 is the input section 3
The output section 38 is controlled by the signal input from 7. The microcomputer 4o is composed of an input section 37, an output section 38, and a control section 39.

FIG. 3 shows a flowchart showing the operation of the microcomputer 4o, and the operation will be explained with reference to this flowchart.

In FIG. 3, the start key 28 is inputted in step 5o, it is determined in step 61 whether the pressed key is the start key 28, and the steps 5o and 50 until the start key 28 is pressed are performed.
Repeat steps 0 to 61. If the start key 28 is pressed in step 51, the process advances to step 52 and the rice cooking process is executed. In step 63, it is determined whether the rice cooking process has finished, and if the rice cooking has not finished, the process returns to step 529.
Steps 52 to 63 are repeated until the rice cooking is completed.

When the rice cooking is finished, proceed to step 54, and turn on the body heater 2.
4 is energized at a energization rate of 3/16, and the lid heater 25 is energized at a energization rate of 3/16. In step 55, the container 21 is detected by the temperature detection means 26.
It is determined in step 56 whether the detected temperature has fallen below the heat retention temperature (71.5° C.), and if it has not fallen below the heat retention temperature, the process proceeds to step 67. Step 6
In step 7, the cancel key 29 is input, and if it is determined in step 58 that the cancel key 29 has not been pressed, the process returns to step 54. Steps 54 to 68. repeat.

If the temperature detected by the temperature detection means 26 falls below the heat retention temperature in step 56, the process proceeds to step 59, where the temperature detection means 26 detects the temperature of the container 21 again. If the bottom temperature has not reached the heat retention temperature (71.5°C) in step 6o, in step 61 the body heater 24 is energized at a energization rate of 15/16, the bottom heater 23 is 1/16, and the lid heater 26 is energized at a energization rate of 8/16. However, if the temperature exceeds the keep-warm temperature, step 62
energization of the bottom heater 23, body heater 24, and lid heater 25 is stopped.

After executing steps 61 and 62, the process proceeds to step 63, where the cancel key 29 is input. If it is determined at step 64 that the cancel key 29 has not been pressed, the process returns to step 69. Steps 59 to 64 are repeated until it is determined in step 64 that the cancel key 29 has been pressed.

When the cancel key 29 is pressed in steps 58 and 64, the process proceeds to step 65, stops energization of all heaters, and returns to step 5o.

Page 10 As described above, according to the electric rice cooker of the embodiment of the present invention, after moving from the rice cooking process to the warming process, the body heater 24 and the lid heater 25 are heated until the temperature drops below the warming temperature to prevent dew from forming on the lid. Since dew is controlled so that it does not occur, dew does not fall on the rice and deteriorate the taste of the rice. Further, after the temperature drops below the heat retention temperature, the bottom heater 23, body heater 24, and lid heater 25 are heated to control the temperature of the container 21 to reach the heat retention temperature, and at the same time prevent dew from forming inside the container. can.

In addition, the bottom cover 23 in the embodiment shown here is as follows:
There are no particular problems with the electromagnetic induction heating method.

Effects of the Invention As is clear from the above embodiments, according to the present invention, when the temperature of the container is high and a large amount of water vapor is generated immediately after entering the warming process, the body heater and the lid heater are heated. There is no dew forming on the inside of the lid, and the dew falls onto the rice, giving it a delicious taste.

Strength without deteriorating the shape etc. Also, 11 of the container
/ Even if the bottom temperature falls below the keep-warm temperature, the bottom heater, body heat and lid heater control the temperature of the container to keep the rice warm and prevent any dew inside the container. can be prevented from occurring.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an electric rice cooker according to an embodiment of the present invention.
Fig. 2 is a specific circuit diagram of the electric rice cooker, Fig. 3 is an operation flowchart of the microcomputer in the electric rice cooker, Fig. 4 is a vertical cross-sectional view of a conventional electric rice cooker, and Fig. 5 is a diagram of the conventional electric rice cooker. It is an operation flowchart of an electric rice cooker. 21...container, 22...lid, 23...
... Bottom heater, 24 ... Body heater, 25.
...Li upper heater 26...Temperature detection means, 27...Control means.

Claims (1)

[Claims] A container with a lid on the top and containing rice and water, a bottom heater that heats the bottom of the container, a body heater that heats the side surface of the container, and a lid heater that heats the inside of the lid of the container. , comprising a temperature detecting means for detecting the temperature of the container, and a control means for inputting a signal from the temperature detecting means, and the control means controls the output of the temperature detecting means to be regulated immediately after entering the warming step from the rice cooking step. The lid heater and the body heater are energized at a constant energization rate until the temperature reaches the predetermined heat retention temperature. An electric rice cooker in which a bottom heater, the body heater, and the lid heater are each controlled to be energized at a constant energization rate or to be de-energized.