JPH0655182B2 - rice cooker - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rice cooker, and more particularly to a microcomputer-controlled rice cooker that has been widely used in recent years.

2. Description of the Related Art Conventionally, rice cookers have been detecting the temperature of the bottom of the inner pot with a temperature sensor and adjusting the heat to finish the so-called "beginning choro choro medium pappa ..." delicious rice. Especially in the cooking process after boiling, which is equivalent to "slowly blow fire", when the amount of cooked rice is small, the amount of heat is reduced so that it does not spill, and when the amount of cooked rice is large, the heat is convected to the top. The amount of heating is increased. For this reason, it is necessary to judge the amount of cooked rice, and generally it is judged by the difference in the temperature rise curve of the temperature sensor when heating with the rice cooker in the process of "medium papper". That is, the less the amount of water is, the faster the boiling water is boiled, and the smaller the amount of cooked rice is, the steeper the temperature rise curve is.

The above-mentioned rice cooking operation is the operation of the normal rice cooking mode premised on normal use, but if the temperature for judging the amount of cooked rice is already exceeded at the start of cooking rice, there is a problem that the amount of rice cooked cannot be correctly judged. . To deal with this problem, an abnormal rice cooking mode is provided, and when the temperature sensor temperature exceeds the temperature (higher than normal) at which the amount of rice cooked cannot be judged correctly at the start of rice cooking, it is switched to the abnormal rice cooking mode. . In the abnormal rice cooking mode, rice is cooked at a constant heating amount (intermediate heating amount that can handle small or large amounts), regardless of the amount of rice cooked.

In the conventional rice cooker of this type, the normal rice cooker mode and the abnormal rice cooker mode are selected by judging by the temperature of the temperature sensor immediately after the user starts the rice cooker or after a fixed time after the start operation.

Problems to be Solved by the Invention However, according to the conventional method, if the inner pot is stored in the main body and the rice cooker switch is operated with the main body and the temperature sensor warm, such as immediately after heat retention or immediately after cooking rice, even if the inner pot is cold, the temperature sensor Depending on the followability, there was a problem that the temperature sensor did not immediately reach a low temperature and the abnormal rice cooking mode was selected.
As a result, in the abnormal rice cooking mode, since the rice is cooked with constant power regardless of the amount of rice cooked, there is a problem that the rice cannot be cooked deliciously compared to the normal rice cooking mode. In order to solve this problem, the user does not energize the rice cooking heater for a certain period of time after operating the rice cooking switch, but after the temperature of the temperature sensor and the inner pot become equal, select the mode and start energizing the rice. You can see the bowl, but in this case there is always a pause for a certain time, so there was a problem that the cooking time was long.

Means for Solving the Problems The present invention has been made to solve the above problems, does not erroneously select an abnormal rice cooking mode, and does not unnecessarily lengthen the rice cooking time. To get a rice cooker. Therefore, at the start of rice cooking, the temperature T ₁ of the inner pot before the start of energization of the rice heater, the preset temperature T _{2 of the} inner pot, and the temperature T ₁ ≧ the temperature T ₂ A temperature sensor for detecting the temperature T ₃ of the pot is provided, and mode selection means for selecting the normal rice cooking mode or the abnormal rice cooking mode from the detected temperature is provided. When the temperature T ₁ of the temperature sensor before the start of energizing the rice cooking heater (at the start of rice cooking) is lower than the temperature T ₂ , the mode selecting means selects the normal rice cooking mode and ends the operation of the mode selecting means. Switch to the normal rice cooking mode of the control unit. As a result, instant cooked rice is executed in the normal cooked rice mode. When the temperature T ₁ is higher than the temperature T ₂ , the process waits until a certain time θ elapses through the energization delay means. The temperature T ₃ of the temperature sensor after waiting is also higher than the temperature T ₂ (for a certain period of time θ ₂
If it is above), the abnormal rice cooking mode is selected, but if the temperature T ₃ after this waiting is lower than T ₂ (changed from T ₂ or more to less than T ₂ during a certain time θ), the normal rice cooking mode is selected. To do. After that, the operation of the mode selection means is completed, the mode is changed to the selected mode, and rice cooking is started.

By doing so, the normal rice cooking mode is selected when the temperature T ₁ <T ₂ and the temperature T ₃ <T ₂ , and the abnormal rice cooking mode is selected when the temperature T ₃ ≧ T ₂ .

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

The configuration of this embodiment is as shown in FIG. 1, and FIG. 2 shows a flowchart of the same operation. In the figure, reference numeral 1 is a bottomed cylindrical main body having an opening at the top and accommodating a removable inner pot 2 inside. A temperature sensor 3 is mounted inside the main body 1 so as to be in close contact with the outer bottom of the inner pot 2, and detects the temperature of the inner pot 2. A rice cooking heater 4 is mounted inside the main body 1 so as to be in close contact with the outer bottom of the inner pot 2 and heats the inner pot 2. A lid 5 is attached to the main body 1 so as to be openable and closable so as to cover the openings of the main body 1 and the inner pot 2. Reference numeral 6 is a mode selection means, and 7 is an energization delay means, both of which are built in a control section 8 provided on the inner bottom of the main body 1. This mode selection means 6
The detected temperature T ₁ detected by the temperature sensor 3 before the energization of the rice cooking heater 4 is started is compared with a preset temperature T _2, and if T ₁ <T _{2, the} normal rice cooking mode is selected. At this time,
If T ₁ ≧ T ₂ , compare the temperatures T ₃ and T ₂ of the temperature sensor after elapse of a certain time θ through the energization delay means 7, and if T ₃ <T ₂ , select the normal rice cooking mode and T ₃ ≧ T _{If 2} , the abnormal rice cooking mode is selected. In addition, the energization delay means 7 measures the time of a fixed time θ according to the operating condition of the mode selection means 6. Reference numeral 8 denotes a control unit which is composed of a microcomputer, and has the above-mentioned mode selection means 6, energization delay means 7 and two rice cooking programs of a normal rice cooking mode and an abnormal rice cooking mode.

Next, the operation of this embodiment will be described.

When the user puts washed rice and an appropriate amount of water in the inner pot 2 and operates the rice cooking switch (not shown) according to the operation flow chart of FIG. 2, the rice cooking lamp (not shown) is turned on and the rice cooking is started. Display that. Next, it is compared whether the temperature T ₁ of the inner pot 2 detected by the temperature sensor 3 at this time is higher or lower than the temperature T ₂ preset by the reading mode selection means 6, and the comparison result shows that the temperature T ₁ <temperature In the case of T ₂ , after the normal rice cooking mode is selected as shown in FIG. 3, energization of the rice cooking heater 4 is started according to the rice cooking program stored in the normal rice cooking mode. Further, when the comparison result temperature T ₁ ≧ temperature T ₂ , it is generally considered that the rice cook switch is turned off once during rice cooking or during rice cooking, and the rice cooker is operated again. Regardless, if the temperature sensor 3 is in a high temperature state for some reason until then, the temperature T may depend on the thermal response of the temperature sensor 3.
_It is erroneously judged that ₁ ≧ temperature T ₂ . However, in the present embodiment, in order to prevent this erroneous determination, when temperature T ₁ ≧ temperature T ₂ ,
Immediately, the abnormal rice cooking mode is not selected, and the energization delay means 7 suspends the electricity supply to the rice cooking heater 4 for a predetermined time θ. However, the rice cooking lamp is still lit. Then, after a certain time θ, the temperature T ₃ of the inner pot 2 detected again by the temperature sensor 3 is compared with the temperature T ₃ and the temperature T ₂ by the reading mode selection means 6, and the comparison result temperature T ₃ ≧ temperature T ₂ . For example, as shown in Fig. 4, the temperature of the inner pot 2 is still high even after a certain time θ, so it is definitely judged as an abnormal state and the abnormal rice cooking mode is selected, and the rice cooking heater is operated according to the rice cooking program stored in the abnormal rice cooking mode. Energization to 4 is started. If temperature T ₃ <temperature T ₂ , the fifth
As shown in the figure, it means that the temperature is cooled from the temperature T ₁ to the temperature T _{3 within a} certain time θ, and the normal rice cooking mode is selected by the mode selecting means 6 and the rice is put in the normal rice cooking mode. Power on the rice cooking heater 4 is started according to the rice cooking program.

The operation of the above-described configuration of the present invention will be described below according to the use situation.

When the rice cooker (including the temperature sensor) is at room temperature, and the rice and water inside the inner pot are also at room temperature, where rice is cooked normally (Fig. 3).

Since the temperature T ₁ is lower than T ₂ , the mode selection means immediately
Normal rice cooking mode is selected and executed.

When rice is interrupted during a rice cooker due to a power failure or the like and rice is restarted, and both the rice cooker and the inner pot are extremely hot (T ₂ or higher) (Fig. 4).

Naturally, the temperature sensor also has a temperature of T ₂ or higher at a high temperature, so the temperature T ₁
Becomes T ₂ or more, the temperature does not drop even during the constant time θ in the energization delay means, and the temperature T ₃ also becomes T ₂ or more, and the abnormal rice cooking mode is selected and executed by the mode selecting means.

A case where rice cooking is interrupted due to a power failure or the like in the middle of rice cooking and rice cooking is restarted, and the temperature in the inner pot is not high (T ₂ or more) at the beginning of rice cooking (Fig. 5).

In the bobbin in less than T _2, the temperature sensor may have a T ₂ or more by the heat effect of the cooking heater, temperature T ₁ of the waiting for a certain time θ of energization delay means T ₂ above are performed . Since the temperature of the temperature sensor adjusts to the temperature in the inner pot during θ, it becomes less than T ₂ , and the temperature T ₃ becomes less than T ₂ .
Normal rice mode is selected, and cook rice again in normal rice mode.

Rice and water in the inner pot are at about room temperature, but when the rice cooker (including temperature sensor) is hot, such as immediately after heat retention or rice cooking (Fig. 5).

When the user starts rice cooking immediately after inserting the inner pot into the rice cooker, it takes time for the temperature sensor to cool down to the temperature of the inner pot, so T ₁ is higher than T ₂ compared to the initial T _1. Become. Therefore, the energization delay means waits for θ. During θ, the temperature of the temperature sensor adjusts to the inner pot and drops, so the temperature T ₃ after θ becomes lower than T ₂ , and the normal rice cooking mode is selectively executed.

As described above, in the configuration of the present invention, the rice is immediately cooked in the normal use condition, and only when the temperature is higher than T ₂ , wait for a certain time θ to judge again whether the temperature is really high. I accidentally selected the abnormal rice cooking mode,
Even if the cooked rice is inferior to the cooked rice in the normal cooked mode, or the judgment is uniformly delayed in order to prevent erroneous judgment, the cooked rice is not wastefully delayed in the normal cooked mode.

EFFECTS OF THE INVENTION As described above, according to the present invention, the temperature of the inner pot before starting rice cooking, the preset temperature of the inner pot, the temperature of the former ≧ the temperature of the latter by the mutual comparison of the temperature of the inner pot after a certain period of time, etc. It is possible to obtain a rice cooker that does not erroneously select the abnormal rice cooking mode and does not unnecessarily lengthen the rice cooking time.

[Brief description of drawings]

FIG. 1 is a sectional view of a rice cooker according to an embodiment of the present invention, FIG.
The figure is a flow chart of the same operation, and FIGS. 3, 4, and 5 are explanatory views of the same operation. FIG. 3 shows the case where the rice cooker and the inner pot are cooked from a normal state at about room temperature. When the rice cooker and the inside of the inner pot are cooked from a high temperature state after recovery from a power failure, the rice cooker (including the temperature sensor) has a high temperature and the inside of the inner pot is at room temperature, as shown in Fig. 5 immediately after keeping it warm. This is the case. 1 ... body, 2 ... inner hook, 3 ... Temperature sensor, 4 ... cooking heater, 6 ... mode selecting means, 7 ... current delaying means, theta ... predetermined time, T _1, T _2, T ₃ ... temperature.

Claims (1)

[Claims] 1. A removable inner pot (2) housed in the main body (1).
, Rice cooker heater (4) that heats the inner pot (2), temperature sensor (3) that detects the temperature of the inner pot (2), and mode selection means that selects either normal rice cooker mode or abnormal rice cooker mode
(6) and energizing the rice cooking heater (4) are started for a certain time (θ)
An energization delay means (7) for delaying is provided, and the mode selection means (6) detects the temperature (T ₁ ) of the temperature sensor (3) before starting the energization of the rice cooking heater (4) (at the start of rice cooking), When the temperature is lower than the preset temperature (T ₂ ), the normal rice cooking mode is selected, and when the temperature is higher than the preset temperature (T), it waits for a certain time (θ) through the energization delay means (7), and waits for a certain time (θ). when the temperature sensor (3) of the temperature (T ₃₎ is lower than the preset temperature (T ₂₎ selects the normal cooking mode after, if higher than the temperature (T ₃₎ is preset temperature (T ₂₎ A rice cooker characterized by selecting an abnormal rice cooking mode.