JPH0630843A - Rice boiler - Google Patents

Abstract

PURPOSE:To provide a rice boiler preventing such deterioration of food taste that the boiled rice under heat retention is locally dried and solidified or whitened and softened by dew condensation and capable of tastily retaining heat. CONSTITUTION:A rice boiler is provided with a container having a cover, a cover heater 14 heating the cover of the container, temperature detecting means 15, 16 detecting the temperatures of the cover and the bottom of the container, and a control means 20 inputted with the signals of the temperature detecting means 15, 16 and controlling the cover heater 14, the heat retention process is started after the rice boiling process is completed, and the cover heater 14 is controlled by temperature for a fixed time then by the excitation factor thereafter until the preset heat retention temperature is reached. The control temperature and excitation factor are changed with the passage of time respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rice cooker having a heat retaining function.

[0002]

2. Description of the Related Art Recent rice cookers having a heat-retaining function are naturally capable of cooking rice, and as a matter of course, there has been a demand for a heat-retaining function that can keep the food delicious.

A conventional rice cooker of this type is shown in FIGS.
Will be described with reference to. As shown in FIG. 3, a container 12 provided with a lid 11 at the top for containing rice and water, and this container 12
A protective frame 13 for supporting the lid 11, a lid heater 14 for heating the inside of the lid 11, a bottom temperature detecting means 15 for detecting the temperature of the bottom portion of the container 12, and a lid temperature detecting means 16 for detecting the temperature of the lid 11. The protective frame 13 has a bottom heater 17 for heating the bottom portion of the container 12, the upper portion of the protection frame 13 has a body heater 18 for heating the side surface portion of the container 12, a bottom temperature detecting means 15 and a lid temperature detecting means 16. Input the signal from the lid heater 14
And a control circuit board 19 for controlling the energization rates of the bottom heater 17 and the body heater 18.

Next, the operation of this rice cooker will be described. In the rice cooking process, the lid heater 14 is controlled by the signal from the lid temperature detecting means 16, and the bottom heater 17 and the body heater 18 are controlled by the control circuit board 19 by the signal from the bottom temperature detecting means 15, respectively. To do.

As shown in FIG. 4, after the rice cooking process is completed, in the heat retaining process, the bottom temperature detecting means 15 sets the prescribed heat retaining temperature T.
During the period until detecting w, the lid heater 14 is controlled at a constant energization rate, and after detecting the heat retention temperature Tw, the lid heater 14, the bottom heater 17, and the body heater 18 are all controlled by a signal from the bottom temperature detecting means 15. The control circuit board 19 controls the energization rate so that the temperature of the container 12 becomes the heat retention temperature Tw, and the heat is maintained.

[0006]

In such a conventional rice cooker, in the heat retaining step, the lid heater is controlled at a constant duty ratio until the bottom temperature detecting means detects the heat retaining temperature. When the room temperature is low, the dew condensed on the inside of the lid drops onto the rice to be whitened, and when the room temperature is high, the surface of the rice is dried and yellowed to deteriorate the taste of the rice.

The present invention is intended to solve the above-mentioned problems, and an object thereof is to keep the temperature of rice so that it does not deteriorate in taste.

[0008]

In order to achieve the above object, the first means of the present invention is to provide a container having a lid on the top for containing rice and water, and a bottom heater for heating the bottom portion of the container. ,
A body heater that heats the side surface of the container, a lid heater that heats the inside of the lid of the container, a bottom temperature detection unit that detects the temperature of the bottom portion of the container, and a temperature of the lid portion of the container. A lid temperature detecting means and a control means for inputting signals from the bottom temperature detecting means and the lid temperature detecting means, and the control means enters from the rice cooking step to the heat retaining step until a predetermined heat retaining temperature is reached. During the period, the energization rate of the lid heater is controlled so as to change with the passage of time.

The second means is the first means, in which the control means goes from the rice cooking step to the heat retention step until the temperature reaches a predetermined heat retention temperature, and the control temperature of the lid heater is changed with time. It is controlled to change.

A third means is the first means, in which the control means enters from the rice cooking process to the heat retention process until a predetermined heat retention temperature is reached, the temperature is maintained for a certain period of time, and then the electrical conductivity is reached. The lid heater is controlled by.

[0011]

According to the present invention, since the humidity in the container is high immediately after the completion of the rice cooking process in the period until the bottom temperature of the container reaches the specified heat retention temperature after the rice cooking process is transferred to the heat retaining process with the above-described structure, the lid is closed. The amount of heating to the lid is increased, and then the heating amount is gradually controlled to be small, so that the lid can be appropriately heated, and the surface of the rice deteriorates in taste such as whitening due to dew drop or yellowing due to drying. Can be prevented.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.
Will be described with reference to.

The basic structure of the rice cooker according to the present invention is as shown in FIG. 3, and a container 12 having a lid 11 on the top and containing rice and water is provided.
A protective frame 13 for supporting the container 12, a lid heater 14 for heating the inside of the lid 11, a bottom temperature detecting means 15 for detecting the temperature of the bottom portion of the container 12, and a lid for detecting the temperature of the lid 11. The temperature detecting means 16, the bottom heater 17 for heating the bottom portion of the container 12 in the protective frame 13, and the body heater 18 for heating the side surface portion of the container 12 in the upper portion of the protective frame 13. Further, as shown in FIG. 1, the lid heater 14 receives signals from the bottom temperature detecting means 15 and the lid temperature detecting means 16.
And a control means 20 for controlling the energization rates of the bottom heater 17 and the body heater 18. The control means 20 is the process storage means 2.
The energization of the heaters 14, 17 and 18 is controlled according to the first process.

Next, the operation of this rice cooker will be described. In the rice cooking process, the lid heater 14 receives signals from the lid temperature detecting means 16, and the bottom heater 17 and the body heater 18 receive signals from the bottom temperature detecting means 15, and the control means 20 controls the energization rate to perform rice cooking. .

As shown in FIG. 2, the lid heater 14 detects the lid temperature only for a certain time t in a period after the rice cooking process and before the bottom temperature detecting means 15 detects the prescribed warming temperature Tw in the heat retaining process. The temperature is controlled by the signal from the means 16, and the control temperature changes according to a predetermined program depending on the humidity and temperature in the container. After the elapse of a certain time t, the lid heater 14 is controlled by the energization rate, and this energization rate also changes according to a predetermined program. After detecting the heat retention temperature Tw, the lid heater 1
4, the bottom heater 17 and the body heater 18 are all controlled by the control means 20 by the signal from the bottom temperature detection means 15 so that the temperature of the container 12 becomes the heat retention temperature Tw.
Keeping warm.

In the present embodiment, the control of the lid heater is shifted from the temperature control to the duty ratio control. However, even if the control temperature is changed while the temperature control is maintained, the duty ratio is controlled while the duty ratio control is maintained. It goes without saying that the same effect can be expected even if changed.

[0017]

As is apparent from the above examples, according to the present invention, when the temperature of the container is high immediately after the heat retention step and a large amount of water vapor is generated and the humidity is high, the lid is heated to a high temperature as in rice cooking. Dew does not occur on the lid because the temperature is controlled to keep it at Also, after a certain period of time, until the heat retention temperature is reached, the bottom temperature of the container is also lowered to some extent, so it is controlled by the energization rate and the heating amount to the lid is not made more than necessary,
The surface of the rice will not be overheated and will not dry. As a result, it is possible to provide a rice cooker that can keep warm deliciously without deteriorating the taste of rice such as whitening of rice due to dew attached to the lid and yellowing due to drying.

[Brief description of drawings]

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

FIG. 2 is a heat insulating process diagram of the rice cooker in one embodiment of the present invention

FIG. 3 is a side sectional view of a rice cooker according to an embodiment of the present invention and a conventional example.

FIG. 4 is a heat insulating process diagram of a rice cooker in a conventional example

[Explanation of symbols]

 11 Lid 12 Container 13 Protective Frame 14 Lid Heater 15 Bottom Temperature Detection Means 16 Lid Temperature Detection Means 17 Bottom Heater 18 Body Heater 20 Control Means

Claims (3)

[Claims] 1. A container provided with a lid on the top for containing rice and water, a bottom heater for heating a bottom portion of the container, a body heater for heating a side portion of the container, and an inside of the lid of the container. Lid heater, bottom temperature detection means for detecting the temperature of the bottom portion of the container, lid temperature detection means for detecting the temperature of the lid portion of the container, signals of the bottom temperature detection means and the lid temperature detection means And a control means for inputting the control means, wherein the control means controls the energization rate of the lid heater to change with the passage of time during the period from the rice cooking process to the heat retention process until the temperature reaches a predetermined heat retention temperature. Rice cooker. 2. The control means enters the heat retention step from the rice cooking step,
The rice cooker according to claim 1, wherein the control temperature of the lid heater is controlled so as to change with the lapse of time during the period until reaching the predetermined heat retention temperature. 3. The control means enters the heat retention step from the rice cooking step,
The rice cooker according to claim 1, wherein the lid heater is controlled by the temperature for a certain period of time until the temperature reaches a predetermined heat retention temperature, and thereafter by the electric conductivity.