JPS62100989A - Complex heating cooker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a composite heating cooker that integrates a microwave oven and an electric oven.

Conventional technology In the case of a conventional combined heating cooker that combines a microwave oven and an electric opener, when the set is operating in microwave oven mode, it is necessary to prevent water vapor generated from food from condensing inside the oven. First, air after cooling the magnetron, which is a high-frequency oscillator, is introduced into the oven to forcefully exhaust water vapor, and when the set is operating in electrically open mode, the air should not be allowed to enter the oven. In addition, the cooling fan 4 is stopped or a damper 12 is provided as shown in FIG.

Problems to be Solved by the Invention However, as mentioned above, when the damper 12 is provided and opened and closed when switching between microwave oven mode and electric oven mode, it makes a loud banging sound when opening and closing, making it uncomfortable to use. A solenoid magnet, etc. is required to open and close the damper, which is very expensive.

Also, if you stop the cooling fan only in the electrically open operation mode without using a damper, the temperature of the control panel, lighting lamp sockets, etc. will rise due to the heat from the open refrigerator, and the cooling air will enter the open refrigerator. Because hot air flows back into the electrical room through the opening, it becomes difficult to ensure the reliability of electrical components such as control components.

As a countermeasure to this problem, a method has been proposed in which the cooling fan operates intermittently at regular intervals during the electrically open operation mode, but in this case, if the set is used in a quiet room,
The problem is that the fan rotation noise is intermittent, making it very noisy and uncomfortable to use. In addition, the cooling of electrical parts is good when the fan is running, but the temperature rises rapidly as soon as the fan stops, so this is not a very preferable method, especially for semiconductor parts and the like.

The present invention solves these problems and provides a complex heating cooker that is inexpensive, does not make harsh noises, and is comfortable to use.

Means for Solving the Problems The composite heating cooker of the present invention is equipped with a heating chamber, a high frequency oscillator, an electric heater, and a cooling fan for cooling the high frequency oscillator and other electric components. teeth,
A wind intake port and an exhaust port are provided so that a part of the air from the cooling fan flows along one wall surface, and the cooling fan has an optimal rotation speed for each heating cooking mode.
It has a variable control configuration. = Effect By controlling the rotation speed of the cooling fan according to the heating cooking mode, when in the electric open mode, the fan is controlled to rotate at low speed continuously, and the gentle wind is flowed along one wall of the open side. without reducing the temperature
It can eliminate the annoying intermittent fan noise and damper opening/closing noise.

Further, electrical components such as semiconductors can be cooled with sufficient reliability by continuous cooling air.

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

In FIG. 1, an electric heater 2 is provided in a heating chamber 1 for use in open cooking, grill cooking, and the like. 3 is a high frequency oscillator that supplies radio waves into the heating chamber for microwave cooking. Reference numeral 4 denotes a cooling fan for cooling the high frequency oscillator and other electrical components. After cooling the high frequency oscillator, a part of the air from the cooling fan is sent through an air guide 6 to an air intake port 6 provided in front of the side wall of the heating chamber. Enter the heating chamber υ, door 7 opens and closes the front opening of the heating chamber
The air flows along the inner wall surface of the heating chamber, and is exhausted to the outside of the refrigerator through an exhaust port 8 provided in front of the side wall opposite to the side wall of the heating chamber where the air intake port 6 is provided.

Therefore, this air does not flow to the center of the refrigerator where the food and heater are located, but cools only the surface of the door before being exhausted.

In Fig. 2, 9 is a fan motor for rotationally driving the cooling fan 4, and a triac 10 is used to drive O1'T-O.
FF controlled. Further, 11 is an electronic control circuit section for sending control signals to the triac 10.

FIG. 3 shows part of the voltage and current waveforms supplied to the differential motor 9 by the triac 10.

The diagonal line part of the waveform indicates the ON state, and the dashed line part indicates the OFF state.
Indicates the status of Therefore, in this figure, the fan motor is energized for two cycles and is de-energized for one cycle.

In the motor load, the phase difference between voltage and current is 40 to 46
°Aru, iE Re type LD O point f 0N-OF
In order to cause F, it is necessary to control the voltage waveform at a point advanced by about 45 degrees.

When the fan motor is operated with the current controlled in this manner, the rotation speed of the fan motor can be reduced to about 60-fold compared to when the fan motor is operated with a continuous current.

Therefore, by changing the energization cycle, it is possible to select a further different rotation speed of the fan motor. However, if you increase the OFF cycle to more than 2 cycles, you will not be able to obtain stable rotation of the fan motor, and low frequency vibration noise will become more likely to occur.
It is desirable to fix the cycle to one cycle and change the rotation speed by varying the ON cycle.

The control status of the cooling fan in each cooking mode is shown in the table below. In microwave oven modes, unless the water vapor generated from the food is exhausted outside the oven, the walls inside the oven and the inner walls of the door windows will become sticky due to condensation. The fan needs to run at full speed to avoid this.

Grilling requires grilling the surface of meat and other foods with high heat, but for this purpose ventilation is also required.
The fan is running at full speed. In addition, by running the fan at full speed, the temperature inside the refrigerator can be prevented from rising too high, and the grill heater can be turned on continuously while the temperature inside the refrigerator remains at an appropriate level, allowing continuous strong infrared rays to be emitted to the food. It is possible to burn the surface of food beautifully.

(If you do not turn the fan, the temperature inside the refrigerator will rise too much,
Because the temperature control thermistor controls the grill heater's energization intermittently, it is not possible to obtain continuous strong infrared radiation from the grill heater. ) When cooking in the oven, the rotation of the fan is reduced to the minimum necessary to cool the electrical and control parts, and weak air is directed along the wall of the door inside the oven, preventing direct air from hitting the food. With proper ventilation, cakes, cutlets, etc. can be finished in a flavorful state without any stickiness.

In simultaneous microwave and oven heating mode, the rotational speed is increased slightly to improve ventilation capacity and cooling capacity for electrical components.

When the oven is in fermentation mode, the fan rotation is stopped to prevent food from becoming too dry.

In oven or grill cooking mode, if you start the cooling fan immediately after the set starts operating, the temperature inside the refrigerator will rise slowly. is not allowed to operate.

Effects of the Invention As described above, the composite heating cooker of the present invention actively introduces the air after cooling the high-frequency oscillator into the oven chamber without using a damper or the like, so as not to directly cool the food. Then, the fan motor is controlled to run at a continuous low speed that is optimal for each cooking mode by controlling the current to flow along the inner surface of the door and controlling the current to the fan motor by turning it on for multiple cycles of the current frequency and turning it off for one cycle. Because of this, it has extremely great effects in the following practical applications.

■ It is possible to ventilate the steam generated from the food and cook the food without sacrificing heating efficiency.

■ There is no need to use dampers, etc., which not only eliminates unpleasant opening/closing noises, but also significantly reduces costs.

■ Since the fan motor can be controlled to rotate continuously at low speed, there is no annoying intermittent rotation noise of the motor.

■ The surface temperature of the door decreases while the heater is heating, improving safety.

[Brief explanation of drawings]

Fig. 1 is a horizontal sectional view of a composite heating cooker according to an embodiment of the present invention, Fig. 2 is an open circuit diagram, Fig. 3 is a waveform diagram of voltage and current applied to the fan motor, and Fig. 4 is a diagram of waveforms of voltage and current applied to the fan motor. FIG. 3 is an explanatory diagram showing the operation of the cooling fan. FIG. 5 is a horizontal sectional view of a conventional composite heating cooker. 2... Electric heater, 3... High frequency oscillator, 4... Cooling fan, 9... Fan motor, 10... Triac substitute Name of person: Patent attorney Toshio Nakao and 1 other person No. 3
Figure □ Time Figure 4

Claims (3)

[Claims] (1) A heating chamber, a high-frequency oscillator, an electric heater, and a cooling fan for cooling the high-frequency oscillator and other electrical components are provided, and the heating chamber is provided with airflow by the cooling fan along one wall. A composite heating cooker having a configuration in which an air intake port and an air exhaust port are provided so that a portion of the air flows, and the cooling fan is variably controlled to have the optimal rotation speed for each heating cooking mode. (2) In the heating cooking mode in which the heater is turned on, the cooling fan is controlled to turn on for multiple cycles and turn off for one cycle, thereby causing continuous rotation at a low speed. Composite heating cooker described in section. (3) The composite heating cooker according to claim 1, wherein the cooling fan is not rotated until the internal temperature reaches the set temperature in the heating cooking mode in which the heater is turned on.