JPH1137471A - Microwave oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microwave oven capable of reducing the number of times of turning-on of a microwave heating means to be executed when a heater heating means is turned off as much as possible while keeping a superior finished state of food. SOLUTION: This microwave oven is provided with a control means 9 for use in performing a heating control operation based on a heating and cooking menu. The control means 9 performs a heating control operation with a heater heating means until its temperature reaches a set temperature T0 determined in correspondence with a heating and cooking menu. After reaching the set temperature T0, a microwave heating means 2 is electrically energized only for a predetermined period of time when an electrical energization of the heater heating means 1 is turned off. After an accumulated electrical energization time Mn or an accumulated times of electrical energization of the microwave heating means 2 reaches a predetermined accumulated time Mk or a predetermined accumulated times, the heating control with the heater heating means is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave oven, and more particularly to a technique for controlling the operation of microwave heating means provided in a microwave oven with a heater.

[0002]

2. Description of the Related Art Conventionally, a microwave oven used for cooking food has a heater heating means 1 such as an electric heater, which has an overall structure as shown in simplified form in FIG. And a microwave heating means 2 provided with a magnetron. In this type of microwave oven, a heating temperature and a heating time required for each of the foods to be stored and cooked in the heating chamber 3 are set in advance and correspond to each selected food. Heat cooking based on the set heating temperature and heating time is to be executed. 3, reference numeral 4 denotes a temperature sensor such as a thermistor disposed on the wall surface of the heating chamber 3, and reference numeral 5 denotes a mounting table on which food is mounted.
Reference numeral 6 denotes a weight sensor of a capacitance type or the like, which is a weight detecting means disposed immediately below the mounting table 5.

[0003] That is, in such a microwave oven, when the food placed on the placing table 5 in the heating chamber 3 is a confectionery such as a cookie or a cake, only the heater heating means 1 is used. Cooking is performed for a relatively short time, and in the case of meat dishes such as meat loaf and roast pork, since the weight of the food is heavy and thick, the heater heating means is started from the beginning of the heating cooking. The heating cooking is performed after alternately or simultaneously using the microwave heating means 1 and the microwave heating means 2. The heating temperature and heating time for meatloaf are 220 ° C and 35 ° C.
Minutes, 200 ° C for roast pork
The heating time is set to about 60 minutes at a heating temperature of 190 ° C. in the case of a baked pork.

When the microwave heating means 2 is used, it is necessary to cool the magnetron with the fan 7, and in this case, the heated air in the heating chamber 3 is discharged outside together with the magnetron cooling air. For,
It takes a long time for the inside of the heating chamber 3 to reach the set temperature, and
As a result, the surface of the food is not sufficiently baked, resulting in dissatisfaction with the finished state of the cooked food. Therefore, unlike the conventional method in which the heater heating means 1 and the microwave heating means 2 are used from the beginning of the heating cooking, as disclosed in Japanese Patent Application Laid-Open No. 62-272026, the food and the inside of the heating chamber 3 are not heated. After the heating by the heater heating means 1 alone is performed until the temperature reaches the set temperature, after the inside of the heating chamber 3 reaches the set temperature, the preset heating is performed by alternately using the heater heating means 1 and the microwave heating means 2. A method has been proposed in which the food is heated until the time reaches, that is, the food is intermittently heated by the microwave heating means 2.

[0005]

When such a method is employed, the microwave heating means 2 turns on within several tens of seconds while the heater heating means 1 is turned off. Will be repeated many times until the process is completed.

However, this microwave heating means 2
Since the life of the magnetron provided by is determined based on the usage time and the number of times of use, repeated use of the magnetron significantly shortens the life, This will lead to a decline. On the other hand, when the heater heating means 1 and the microwave heating means 2 are used alternately, it is necessary to switch the operation between the two by using a relay (not shown). As a result, not only the life of the relay is shortened, but also annoying noise is generated every time the contact is repeatedly switched.

The present invention has been made in view of such inconveniences, and it has been proposed that the number of times the microwave heating means be turned on when the heater heating means is turned off while ensuring good food finishing conditions. It is an object of the present invention to provide a microwave oven configured so as to be able to reduce as much as possible.

[0008]

According to a first aspect of the present invention, there is provided a microwave oven comprising: a heater heating means for heating and cooking food; a microwave heating means; a temperature detecting means for detecting a temperature during heating and cooking; A menu setting means for setting a cooking menu, and a control means for executing heating control based on the heating cooking menu, wherein the control means adjusts a set temperature determined according to the heating cooking menu. Until the heating reaches the set temperature, the heating control is performed, and after the set temperature is reached, the microwave heating means is energized for a predetermined time when the heater heating means is turned off.
The heating control by the heater heating means is performed after the total energizing time or the total number of energizing times of the microwave heating means reaches a predetermined total time or a predetermined total number of times.

A microwave oven according to a second aspect of the present invention comprises:
According to a first aspect of the present invention, the control means determines the predetermined cumulative time or the predetermined cumulative number of times of the microwave heating means in accordance with the heating cooking menu, and then controls the heating.

[0010] The microwave oven according to claim 3 of the present invention comprises:
3. The apparatus according to claim 2, further comprising weight detection means for detecting the weight of the food to be cooked, wherein the control means controls the microwave heating means for a predetermined cumulative time corresponding to the detected weight of the food. Alternatively, it is characterized in that the predetermined cumulative number is increased or decreased.

A microwave oven according to a fourth aspect of the present invention comprises:
The control means measures the time required from the start of heating cooking to the set temperature, and calculates a predetermined total time or a predetermined total number of times of the microwave heating means in accordance with the measured time. It is characterized by increasing or decreasing. A microwave oven according to a fifth aspect of the present invention is the microwave oven according to any one of the first to fourth aspects, further comprising voltage detection means for detecting a power supply voltage, wherein the control means detects the power supply voltage. It is characterized in that the energization time of the microwave heating means is increased or decreased according to the power supply voltage.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing a circuit configuration of a microwave oven according to the present embodiment, and FIG. 2 is a timing chart showing a heating control state in the microwave oven. Since the entire structure of the microwave oven at this time is basically the same as that of the conventional microwave oven, the entire structure will be described with reference to FIG. 3, and in FIG. 1, the same or corresponding parts as those in FIG. Parts are given the same reference numerals. By the way, the operation control technique according to the present embodiment described below sets the predetermined cumulative time of the microwave heating means in advance and checks whether the cumulative energizing time of the microwave heating means has reached the predetermined cumulative time. However, it is a matter of course that the present invention is not limited to such an operation control technique, and a predetermined cumulative number is set in place of the cumulative energizing time, and the cumulative number of the microwave heating means is set. It may be determined whether or not the number of energizations has reached a predetermined cumulative number.

FIG. 1 shows a microwave oven according to this embodiment.
As shown in FIG. 3 and FIG. 3, a heater heating means 1 such as an electric heater for heating and cooking food, a microwave heating means 2 having a magnetron for heating and cooking food, and a temperature detection for detecting a temperature during heating and cooking. A temperature sensor 4 as a means,
The menu includes a menu setting unit 8 which is an operation unit for selecting and setting a heating cooking menu, and a control unit 9 which is a microcomputer which executes heating control based on the heating cooking menu. And this control means 9
When heating the food after being heated to the set temperature T0 by the heater heating means 1 by the heater heating means 1 and the microwave heating means 2, the microwave is supplied only when the heater heating means 1 is turned off. The microwave heating means 2 is repeatedly turned on until the cumulative energizing time Mn of the heating means 2 reaches a predetermined cumulative time Mk of the microwave heating means 2 preset for each food. In addition, the code | symbol 10 in FIG.
11 is a rectifier circuit, 12 is a voltage detection circuit, L1 is a relay for heater heating means, and L2 is a relay for microwave heating means.

That is, for the control means 8, the heating temperature (set temperature T0) and the total heating time Tk determined corresponding to the heating cooking menu are set in advance, and the heater heating means 1 is set. The energizing time of the microwave heating means 2 when the food after being heated to the set temperature T0 corresponding to each food is alternately heated by the heater heating means 1 and the microwave heating means 2, that is, the heater heating means The energizing times M1, M2,... Of the microwave heating means 2 to be turned on each time the off-operation 1 is performed.
And the predetermined cumulative time Mk of the microwave heating means 2 are set in advance. Then, depending on the control means 9,
The total energizing time Mn of the energizing times M1, M2,... When the microwave heating means 2 repeats the ON operation for each food.
Is calculated, and the control means 9 that has determined that the cumulative energizing time Mn has reached the predetermined cumulative time Mk stops the ON operation of the microwave heating means 2. The predetermined cumulative time Mk of the microwave heating means 2
Is determined beforehand to be an optimal time after performing a heating cooking experiment on each of the standardized foods and checking the heating state inside the foods.

Next, the operation of the microwave oven according to the present embodiment will be described with reference to FIG.

First, a food setting key, for example, a meat loaf key 8 provided on a menu setting means 8 which is an operation unit.
When the heating start key (start key) 8b is pressed after pressing a, the relay L1 is turned on, and the meat loaf placed in the heating chamber 3 and the placing table 5 by the heater heating means 1 alone is used. Heating of a certain food is started. Then, as illustrated in FIG. 2, heating only by the heater heating means 1 is continuously performed until the inside of the heating chamber 3 reaches the set temperature T0, and the heating chamber 3 is heated by the temperature sensor 4. When it is detected that the room temperature has exceeded the set temperature T0, the heater heating means 1 stops the ON operation and turns OFF after the relay L1 turns OFF. Further, when the heater heating means 1 is in the off operation, the relay L2 is turned on by the control means 8, and the microwave heating means 2 started to operate in accordance with the on operation of the relay L2 is energized for an energizing time. The food is heated by microwaves only by M1.

Next, when the inside of the heating chamber 3 becomes lower than the set temperature T0 as the heater heating means 1 is turned off, the relay L
After the relay 2 is turned off, the relay L1 is turned on, and the heating of the food and the heating chamber 3 by the heater heating means 1 is restarted. Then, when the temperature in the heating chamber 3 exceeds the set temperature T0 again, the heater heating means 1 is turned off with the turning off of the relay L1, and the relay L2 is turned on by the control means 9 as a result. The microwave heating means 2 heats the food with the microwave for the energizing time M2. Note that the heater heating means 1
Is normally set to about 40 to 60 seconds, and it goes without saying that the energizing times M1 and M2 of the microwave heating means 2 may be the same length.

Further, subsequently, the heater heating means 1 and the microwave heating means 2 repeatedly execute the alternate heating of the food, and the control means 9 controls the heater heating while the alternate heating is repeatedly performed. Whether the total energizing time Mn = M1 + M2 +... Of the microwave heating means 2 which is turned on only when the means 1 is turned off reaches a predetermined cumulative time Mk of the microwave heating means 2 which is preset for each food item. Determine whether or not. And
If the cumulative energization time Mn of the microwave heating means 2 has not reached the predetermined cumulative time Mk, the intermittent heating of the food by the microwave heating means 2 will be continued.

At this time, the total energizing time Mn of the microwave heating means 2 is set to a predetermined total time Mk set in advance.
, The intermittent heating of the food by the microwave heating means 2 is stopped by the control means 9. Note that the number of ON operations of the microwave heating means 2 until reaching the predetermined cumulative time Mk is about 5 to 7 times, which is generally much smaller than in the past.
Further, even after the heating by the microwave heating means 2 is stopped, the heating by the heater heating means 1 is continuously executed until the total heating time Tk set corresponding to each food menu is reached. , And the heating and cooking of the food is completed after waiting for the total heating time Tk to be reached.

According to the above-described procedure, the surface of the food heated by heating only by the heater heating means 1 is hardened, so that the delicious meat juice inside the food is hard to flow out. After the food is gradually heated by the alternating heating of the wave heating means 2 to pass through the fire, the food is heated so as to wrap the whole food only by the heater heating means 1, so that the food is sufficiently heated and finished. Good condition is achieved. In addition, when the inventors of the present invention conducted a heating cooking experiment, experimental results as shown in Table 1 were obtained. According to the experimental results, the total heating time Tk
Is also shortened.

[0022]

[Table 1]

Meanwhile, in the microwave oven according to the present embodiment, the predetermined cumulative time M of the microwave heating means 2 is determined based on a heating cooking experiment on each of the standardized food items.
Since k is determined, the actual amount of each food to be cooked may be different from the standard amount, but in order to deal with such inconvenience, the following configuration is employed. ing. That is, a weight sensor 6 such as an electrostatic capacitance type for detecting the weight W of the food to be cooked is provided as a weight detecting unit immediately below the mounting table 5 disposed in the heating chamber 3 of the microwave oven. The weight W of the food detected by the weight sensor 6 is provided to the control means 9 as data for setting the total heating time Tk required by the food and the predetermined cumulative time Mk of the microwave heating means 2. In the control means 9, the weight Wk of the set standard amount for each food is determined by the weight sensor 6.
The extension or shortening of the predetermined cumulative time Mk of the microwave heating means 2 is executed in addition to the actual amount of weight W detected by the above.

That is, at this time, if the actual weight of the food W is heavier than the standard weight Wk, the predetermined cumulative time Mk of the microwave heating means 2 is extended by the heavier weight, and the weight W becomes greater than the weight Wk. If it is lighter, the predetermined cumulative time Mk of the microwave heating means 2 is reduced by the lighter (Mk = W / Wk). As a result, the cumulative energizing time Mn of the microwave heating means 2 which is turned on only when the heater heating means 1 is deenergized and energized is also extended or shortened according to the predetermined cumulative time Mk. Even if is different from the standard amount, it is possible to ensure both sufficient heating of the food and good finished state without any inconvenience. Needless to say, the cumulative energization time Mn may be changed by changing the energization times M1, M2,..., Or may be changed by changing the number of energization times.

Further, in a microwave oven having no weight detecting means, the operation time is corrected based on the weight of the food according to the following procedure. That is, the heavier the weight of the food to be cooked, the greater the amount of heat absorbed by the food, so that the temperature in the heating chamber 3 heated by the heater heating means 1 is less likely to rise. Become. Therefore, the rising time for each food item, which is set to the standard amount in advance, that is, the heater heating means 1
The heating time required for the heating chamber 3 to reach the set temperature T0 from the start of heating by the heating was determined by a cooking experiment, and the rise time for each food determined by the experiment was set in the control means 9. Then, the control unit 9 determines the rise time required for cooking the actual amount of food by heating.
, And based on the standard rise time, the predetermined cumulative time Mk of the microwave heating means 2 is extended or shortened corresponding to the measured rise time.

Then, as in the case where the weight detecting means is provided, the cumulative energizing time Mn of the microwave heating means 2 is extended or shortened in accordance with the predetermined cumulative time Mk, so that the actual amount of food is reduced. Even if the amount is different from the standard amount, it is possible to ensure both sufficient heating of the food and good finished state without any inconvenience. In addition, when the food is intermittently heated by the microwave heating means 2 and the experiment for obtaining the rise time, correction based on the ambient temperature is also performed as necessary.

Furthermore, in the microwave oven according to the present embodiment, in order to eliminate the influence of the power supply voltage, the power supply voltage stepped down by the low-voltage transformer 10 is DC-converted by the rectifier circuit 11 as shown in FIG. In addition, the DC voltage is divided by the resistors R1 and R2 constituting the voltage detection circuit 12 functioning as voltage detection means, and the divided voltage V0 is read by the control means 9. Since the divided voltage V0 changes in accordance with the power supply voltage, the control means 9 responds to the divided voltage V0 changed in accordance with the power supply voltage, Are to be extended or shortened.

That is, when the power supply voltage is low, the divided voltage V0 becomes low and the heating output of the microwave heating means 2 becomes small, so that the heating using the microwave heating means 2 requires a relatively long time. When the power supply voltage is high, the divided voltage V0 increases, and the heating output of the microwave heating means 2 increases. As a result, the microwave heating means 2
In this case, the time required for the heating performed by using is short. Therefore, the control means 9 in this case has a rating of 1
.. Is changed by changing the energizing times M1, M2,... Of the microwave heating means 2 in response to a change in the power source voltage while using a general power source voltage as a reference. .. Are performed to make the heating energy uniform in each case. In such a configuration, the inside of the food heated by the microwave is hardly affected by a change in the power supply voltage, so that sufficient heating of the food and a good finished state are ensured. Will be able to do it.

[0029]

As described above, in the microwave oven according to the present invention, the heating temperature and the total heating time corresponding to each food to be cooked are set, and the microwave is heated to the set temperature by the heater heating means. After a predetermined cumulative time or a predetermined cumulative number of microwave heating means for alternately heating the food after heating by the heater heating means and the microwave heating means, and only when the heater heating means is turned off, The microwave heating means is repeatedly energized until the total energizing time or the total number of energizing times of the microwave heating means to be turned on reaches a predetermined total time or a predetermined total number of microwave heating means set for each food. Has been done.

As a result, the microwave heating means does not repeat the ON operation until the heating and cooking of the food is completed. The effect that good state can be ensured is obtained. Then, as a result of the reduced use frequency of the microwave heating means, the service life of the magnetron and the relay can be extended, and the noise generated from the relay at the time of contact switching can be suppressed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a circuit configuration of a microwave oven according to an embodiment.

FIG. 2 is a timing chart showing a heating control state in a microwave oven.

FIG. 3 is an explanatory diagram showing the overall structure of a microwave oven according to the present embodiment and a conventional embodiment.

[Description of Signs] 1 Heater heating means 2 Microwave heating means 4 Temperature sensor (temperature detecting means) 8 Menu setting means 9 Control means Mn Total energizing time Mk Predetermined cumulative time

Claims (5)

[Claims] 1. A heater heating means and a microwave heating means for heating and cooking food, a temperature detecting means for detecting a temperature at the time of heating cooking, a menu setting means for setting a heating cooking menu, and a heating cooking menu. Control means for performing heating control, wherein the control means executes heating control by the heater heating means until a set temperature determined according to the heating cooking menu is reached, and After the set temperature is reached, the microwave heating means is energized for a predetermined time when the heater heating means is turned off, and the heater is turned on when the cumulative energizing time or the total number of energization times of the microwave heating means reaches the predetermined cumulative time or the predetermined cumulative number of times. A microwave oven which performs heating control by heating means. 2. The microwave oven according to claim 1, wherein the control means controls heating after determining a predetermined cumulative time or a predetermined cumulative number of times of the microwave heating means corresponding to the heating cooking menu. A microwave oven characterized in that: 3. The microwave oven according to claim 2, further comprising weight detection means for detecting the weight of the food to be cooked, wherein the control means controls the microwave heating in accordance with the detected weight of the food. A microwave oven for increasing or decreasing a predetermined cumulative time or a predetermined cumulative number of means. 4. The microwave oven according to claim 2, wherein the control means measures a time required from the start of heating and cooking to the set temperature, and a predetermined cumulative time of the microwave heating means corresponding to the measured time. Alternatively, the microwave oven increases or decreases a predetermined total number of times. 5. The microwave oven according to claim 1, further comprising voltage detection means for detecting a power supply voltage, wherein said control means responds to the detected power supply voltage. A microwave oven for increasing or decreasing the energizing time of microwave heating means.