JPH0552342A - Microwave heating and cooking device - Google Patents

Abstract

PURPOSE:To prevent the surface of cooked rice from being dried even through the rice is not wrapped when the cooked rice is heated and cooked. CONSTITUTION:A side plate of an inner case 2 having at its inside part a cooking chamber 3 is formed with a humidifying opening part 2c and its outside part is provided with an ultra-sonic humidifier 16. The ultra-sonic humidifier 16 is comprised of a water tank 16a for storing humidifying water and a vibration exciting part 16a for vibrating water with ultra-sonic wave. In the case where a magnetron 14 is operated to heat cooked rice and cook it, the ultra- sonic humidifying 16 is properly operated according to the sensing results of a gas sensor 15 and water vapor is supplied to the cooking chamber 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency cooking apparatus for cooking an object to be cooked with high frequency.

[0002]

2. Description of the Related Art For example, in a microwave oven, when an object to be cooked is placed on a turntable in a cooking chamber and a cooking start switch is operated, microwaves are generated in the cooking chamber by the oscillation output of a magnetron provided inside. Is irradiated to heat the food to be cooked.

In this case, depending on the food to be cooked, steam may be generated as the heating progresses, and when the water content of the food to be cooked is reduced, for example, rice becomes dry and hard. The food to be cooked is wrapped to prevent steam from escaping and then cooked.

[0004]

However, the work of applying the wrap in this way is troublesome, and since the wrap is hot when it is removed after the heating is finished, there is a risk of causing burns or other injuries, which is troublesome. It has become.

The present invention has been made in view of the above circumstances, and an object thereof is to easily heat and cook food in a dry state without performing a troublesome work such as wrapping even when warming rice. It is to provide a high-frequency heating cooking device that can.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a high-frequency heating cooking apparatus for heating an object to be cooked in a cooking chamber with high frequency, and detects the amount of water vapor in the cooking chamber. A feature is that a sensor and a humidifying device for humidifying the cooking chamber are provided, and the humidifying device is drive-controlled based on a detection output of the sensor during heating according to the type of the object to be cooked. ..

[0007]

According to the high-frequency heating cooking apparatus of the present invention, for a food to be cooked, such as rice, which does not want moisture to escape with heating, the humidifying device is driven and controlled appropriately according to the output of the sensor. Since the cooking is carried out in a humid condition, there is no need to carry out the work of applying a wrap to prevent the moisture from escaping, and the cooking can be carried out easily.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a microwave oven will be described below with reference to the drawings.

FIG. 2 shows the external appearance of the microwave oven. An inner case 2 is provided inside the main body case 1 to form a cooking chamber 3 in which an object to be cooked is housed and cooked. A turntable 4 is provided on the inner bottom of the inner case 2 to rotate the food to be cooked. A door 5 is provided in the main body case 1 so as to close the front opening of the inner case 2. An operation panel 6 is arranged on the front surface of the main body 1 to the right of the door 5. The operation panel 6 is provided with various operation switches 7 and a display unit 8 for displaying a cooking state and the like. The operation switch 7 includes, for example, an automatic cooking key 7a and a rice warming key 7
b, a time setting key 7c, etc. are provided.

In FIG. 1, which shows the interior of the main body 1 in a longitudinal section, a turntable 4 is rotatably supported by a rotary shaft 4a, and is rotatably driven by a drive mechanism 9 provided under the inner case 2. It has become. Drive mechanism 9
Is provided with a turntable motor 10 and a weight sensor 11 for detecting a load applied to the rotating shaft 4a.
Are arranged.

An excitation port 12 is formed on the side plate of the inner case 2, and a magnetron 14 is attached to the excitation port 12 via a waveguide 13. Further, an exhaust port 2a is formed in the upper part of the inner case 2 and an exhaust passage 2b is formed. A gas sensor 15 is arranged inside the exhaust passage 2b. The gas sensor 15 detects the generation amount of water vapor and other gases, and outputs the detected gas amount as a voltage, and has a characteristic that the output voltage decreases as the detected gas amount increases. ing.

An opening 2c for humidification is formed on the side plate of the inner case 2, and an ultrasonic humidifier 16 as a humidifier is arranged outside the opening 2c. The ultrasonic humidifying device 16 includes a water tank portion 16a that stores water for humidification and an exciting portion 16b that excites water by ultrasonic waves.
Water vapor is introduced into the cooking chamber 3 via c.

A fan motor 17 is provided on the inner surface of the body case 1.
And a blower 19 including a fan 18 is provided,
When the blower 19 is operated, outside air is taken in through an intake port (not shown) of the main body case 1, the magnetron 14 is air-cooled and flows into the cooking chamber 3, and the outside of the main body case 1 is passed through the exhaust port 2a and the exhaust passage 2b. It is designed to be discharged to.

FIG. 3 shows an electrical block configuration. The microcomputer 20, which is a control means for controlling the overall operation, controls the drive of each part according to a cooking control program stored and stored in advance. The operation switch 7, the gas sensor 15 and the weight sensor 11 are connected to the input terminal of the microcomputer 20, the display unit 8 is connected to the output terminal, and the magnetron 1 is connected.
4, the fan motor 17, the turntable motor 10, and the ultrasonic humidifier 16 are connected via drive circuits 21 to 24, respectively.

Next, the operation of this embodiment will be described with reference to FIGS. 4 to 7. In addition, here, the heating cooking of "rice warming" which requires humidification control will be described, and FIGS. 4 and 5 show flowcharts of the heating cooking program for "rice warming". In addition, in FIG. 6, when one and two cups of heating are performed at room temperature (hereinafter referred to as "room temperature rice") and frozen rice (hereinafter referred to as "frozen rice"), respectively. 7 shows a time transition of the ratio of the detection voltage of the gas sensor 15 of FIG.

Now, for example, consider the case of heating one cup of "room temperature rice" as the food A to be cooked. That is, when one cup of "room temperature rice" is placed and housed on the turntable 4 of the cooking chamber 3 and the rice warming key 7b is operated to start cooking, the microcomputer 20 starts the cooking process shown in FIGS. 4 and 5. Start cooking operation according to the flow chart of the program.

The microcomputer 20 first reads the detected weight from the weight sensor 11 (step S).
1) After this, time counting is started (step S
2). Based on the value of the weight detected by the weight sensor 11, the microcomputer 20 recognizes that one cup of rice is included. Subsequently, the microcomputer 20 performs a cleaning operation in which the blower 19 is operated for 5 seconds to discharge the residual gas in the cooking chamber 3 (step S3), and then the output voltage of the gas sensor 15 is set to the maximum voltage Vmax. Read (step S4).

Subsequently, the microcomputer 20 drives the magnetron 14 to start the heating operation by the microwave (step S5), and 50 from the start of the time count.
Wait for seconds to elapse (step S6). When the microcomputer 20 determines “YES” in step S6, the output voltage of the gas sensor 15 is read again as VA (step S7), and the output voltage VA is calculated from Vmax based on the following arithmetic expression (1). Change rate Gh
Is calculated (step S8).

Gh = (Vmax-VA) / Vmax (1) The microcomputer 20 determines whether or not the rate of change Gh calculated in step S8 is 0.05 or more, that is, the output voltage of the gas sensor 15 changes by 5% or more. Whether or not it is determined in step S9. In this case, as shown in FIG. 6, when the food to be cooked A is "room temperature rice", the temperature gradually rises as the cooking progresses, and the water contained in the rice is released into the cooking chamber 3 as water vapor. Therefore, the microcomputer 20 determines “YES” in step S9, and proceeds to step S10.

That is, the microcomputer 20 determines whether or not it is "room temperature rice" in this determination step S9. When the processing proceeds to step S10, it is determined that the food A to be cooked is "room temperature rice". The cooking time and cooking conditions for one cup of "room temperature rice" are set together with the detection result of S1.

In this case, the cooking time is "room temperature rice",
Depending on the distinction of "frozen rice" and the amount of 1 or 2 cups, etc.
It is set as shown in FIG. 7 based on the data stored in advance. As the cooking condition, the heating pattern is changed according to "room temperature rice" or "frozen rice", and the operating condition of the humidifier is determined according to one cup or two cups.

Now, when the cooking time and conditions for one "room temperature rice" are set, the microcomputer 20 proceeds to step S11 to read the output voltage of the gas sensor 15 as VB, and to the next output voltage VB, The rate of change Gh 'from VA is obtained based on the above-described arithmetic expression (2) (step S12).

Gh ′ = (VA−VB) / VA (2) The microcomputer 20 determines whether the change rate Gh ′ calculated in step S12 is 0.02 or more, that is, the output voltage of the gas sensor 15 is VA. It is determined in step S13 whether or not the value has changed by 2% or more. Then, when it is determined to be "NO" here, that is, when the amount of generated steam is still small, the process returns to step S11 to read the output voltage VB of the gas sensor 15, and similarly steps S12 and S13 are repeated.

When the rate of change Gh 'reaches 0.02 or more and the microcomputer 20 determines "YES" in step S13, the microcomputer 20 proceeds to step S14 and operates the ultrasonic humidifier 16 for 10 seconds. Then, steam is sent into the cooking chamber 3 (see FIG. 7B). By operating the ultrasonic humidifier 16 for 10 seconds, sufficient steam is supplied into the cooking chamber 3. This suppresses the progress of drying of the surface portion due to generation of water vapor from the surface portion as the heating of "room temperature rice" progresses.

When the heating operation progresses and the cooking time expires in this way, the microcomputer 20 determines "YES" in step S15, stops the humidification control (step S16), and operates the magnetron 14. To stop the microwave output (step S1
7), the program ends.

Next, when there are two "room temperature rice" serving as the food to be cooked A, the microcomputer 20 detects the weight of the two servings in the above-mentioned step S1, and the step S1.
At 10, the cooking time and cooking conditions are set accordingly (see FIGS. 7 (c) and 7 (d)). Then, the humidification control corresponding to two "room temperature rice" is carried out through the same steps as described above.

On the other hand, when the food A to be cooked is "frozen rice", the microcomputer 20 controls the heating operation as follows. That is, the microcomputer 2
In the same manner as described above, when the value of 0 goes to step S9 through steps S1 to S8, the value of the change rate Gh at this time is small, unlike the above, and is judged as "NO". That is, as shown in FIG. 6, "frozen rice" hardly generates steam until it is thawed.

As a result, the microcomputer 20
Shifts to step S18 and sets the cooking time and cooking conditions assuming that the food A to be cooked is "frozen rice" (see FIGS. 7 (e), (f), (g) and (h)). .. At this time, the cooking condition is initially set to a value according to the defrosting condition by changing the duty of the on / off, not the maximum output of the magnetron 14 to perform the defrosting, and after that, when the defrosting is completed, the maximum output is set. It is designed to be heated.

When the microcomputer 20 proceeds to step S19, it again reads the output voltage of the gas sensor 15 as VA and calculates the change rate Gh (step S20). Then, it is determined whether the obtained change rate Gh is 0.05 or more (step S21),
If "NO" is determined, the process returns to step S19 because the cooking time has not expired in step S22. After that, the microcomputer 20 has the change rate Gh of 0.0.
Steps S19 to S22 are repeated until it becomes 5 or more and it is judged "YES" in step S21.

As a result, the timing when the frozen rice is thawed and the temperature rises to generate steam is detected. Then, the microcomputer 20
When it is determined to be "YES" in step S21, it is determined that the "frozen rice" being heated has reached the same state as the "room temperature rice", and the process proceeds to step S11. Thereafter, the microcomputer 20 performs steps S11 to S17 in the same manner as in the case of "room temperature rice" to perform the heating operation while performing the humidification control so that the surface portion of the rice does not become a dry state and cooking is performed. Done.

It should be noted that the completion of the cooking time is judged in step S22 because, for example, when "frozen rice" is wrapped in wrap and cooked by heating, the generation of water vapor is reduced, and "step S21" is executed. This is because when it is not determined to be “YES”, only the heating operation is performed as it is, and the heating and cooking operation can be ended when the cooking time is completed. In addition, similarly, when the cooking object A is another food item that generates very little steam, not the "frozen rice", the heating and cooking operation can be ended without performing unnecessary humidification control. Is.

According to this embodiment, the microcomputer 20 controls the humidification of the ultrasonic humidifier 16 in accordance with the voltage detected by the gas sensor 15 during cooking. Whichever "frozen rice" is used as the food A, the heating operation can be performed without drying the surface portion of the rice without applying the wrap, and thus the troublesome work of applying the wrap can be eliminated. , Don't feel hot when removing the wrap after cooking.

[0033]

As described above, according to the high-frequency cooking apparatus of the present invention, according to the output of the sensor, an object to be cooked, such as rice, which does not want moisture to escape with heating Since the heating control is performed in a moderately humidified state by driving the humidifier to control the heating, it is not necessary to put on a wrap to prevent moisture from escaping or to remove the wrap after cooking. It has an excellent effect that cooking can be easily performed.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional front view showing an embodiment of the present invention.

[Fig. 2] External perspective view

FIG. 3 is a block diagram

[Fig. 4] Flow chart of cooking program

[Figure 5] Continuation flow chart of the cooking program

FIG. 6 is a diagram showing a temporal transition of a sensor output ratio according to a rice state.

FIG. 7 is a diagram showing the content of control according to the state of rice

[Explanation of symbols]

1 is a main body case, 2 is an inner case, 3 is a cooking chamber, 4 is a turntable, 6 is an operation panel, 7 is an operation switch, 11
Is a weight sensor, 14 is a magnetron, 15 is a gas sensor (sensor), 16 is an ultrasonic humidifier (humidifier), 19
Is a blower, and 20 is a microcomputer (control means).

Claims (1)

[Claims] 1. An object to be cooked in a cooking chamber by high frequency heating, comprising a sensor for detecting the amount of water vapor in the cooking chamber, and a humidifying device for humidifying the cooking chamber. A high-frequency heating cooking apparatus, which drives and controls the humidifying device based on a detection output of the sensor during cooking according to the type of food to be cooked.