JPH01143185A - Complex cooking apparatus - Google Patents

Abstract

PURPOSE:To enable the easy and quick setting of a cooling time at all times by setting initially a cooking time respectively to zero at the time of setting high-frequency induction heating and to a maximum value at the time of setting electromagnetic induction heating, and increasing or decreasing a set cooking time depending upon the operation of a time setting dial. CONSTITUTION:A display 12 shows a present time when cooking is not made. Once high-frequency induction heating is set by pressing a range key 6, a cooking time is initially set to zero minute and a set cooking time is increased via the turning operation of a time setting dial 11 toward an increment direction (or clockwise direction). The set cooking time is reduced correspondingly via the turning operation of the dial 11 toward a decrement direction (or counter-clockwise direction). Also, once electromagnetic induction heating is set by pressing a cooking plate key 7, the cooling time is initially set to a maximum value and the set cooling time is shortened via the turning operation of the dial 11 toward the decrement direction. And the set cooking time is increased correspondingly via the turning operation of the dial 11 toward the increment direction. According to the aforesaid construction, a cooking time can always be set easily and quickly regardless of the heating system of a highfrequency induction heating or electromagnetic induction heating.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a composite cooking device that enables high-frequency dielectric heating as a microwave oven and electromagnetic induction heating as an electromagnetic cooker.

(Prior Art) Recently, a composite cooker equipped with an inverter circuit and capable of high-frequency dielectric heating as a microwave oven and electromagnetic induction heating as an electromagnetic cooker has been developed and is being put into practical use.

In such a composite cooking device, it is common to use a common timer for controlling the cooking time and a common operator for setting the cooking time.

(Problems to be Solved by the Invention) However, while the cooking time of high-frequency dielectric heating is relatively short, the cooking time of electromagnetic induction heating is often quite long. For this reason, setting the cooking time during electromagnetic induction heating is extremely troublesome.

This invention was made in view of the above circumstances,
The purpose is to provide a complex cooking device with excellent operability that allows easy and quick cooking time setting regardless of whether high-frequency dielectric heating or electromagnetic induction heating is used.

[Structure of the invention] (Means for solving the problem) Means for initially setting the cooking time to "zero" when setting high frequency dielectric heating, and setting the cooking time to "maximum value" when setting electromagnetic induction heating. A means for initial setting, a time setting knob having an endless operation range, and a means for increasing or decreasing the set cooking time in accordance with the operation of the time setting knob are provided.

(Function) When setting high frequency dielectric heating, that is, when cooking with a relatively short cooking time, the cooking time is initially set to "zero". When setting electromagnetic induction heating, that is, for cooking that often requires a long cooking time, the cooking time is initially set to the "maximum value".

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 2, reference numeral 1 denotes a main body of the composite cooking device, which has a door 2 pivotably supported on the front surface so as to be freely openable and closable, and a top plate 3 on the upper surface.

A heating chamber (not shown) is provided in the main body 1 corresponding to the door 2, and a magnetron 44 (described later) is installed in the heating chamber.
High frequency radio waves are supplied from Furthermore, a turntable (not shown) for placing food is provided in the heating chamber.

Inside the main body 1 corresponding to the top plate 3, there is a heating coil 50, which will be described later, spaced apart and facing the bottom surface of the top plate 3.
is provided.

A corner portion where the front surface and the top surface of the main body 1 are connected serves as an operating section 4. This operation section 4 is sloped for easy viewing and operation, and includes a tack plate key 5 for setting electromagnetic induction heating, a range key 6 for setting high frequency dielectric heating, and a tuck plate key 5 for setting high frequency dielectric heating. key 7, down key 8 for output setting, start key 9, cancel key 10,
A time setting knob 11 and a display 12 are provided.

The rotation operation range of the time setting knob 11 is endless, with clockwise rotation increasing and counterclockwise rotation decreasing.

The control circuit is shown in FIG.

20 is a commercial AC power supply, and a fuse 21 is connected to the power supply 20.
Door switch 22a1 Door switch 22b1 A door monitor switch (short switch) 22C is connected via magnetron thermal 23.

A heating indoor lighting lamp (interior lamp) 24 is connected to the power source 20 via a fuse 21, a door switch 22a1 relay, a contact 72a, a main relay contact 71a1, a door switch 22b1, and a magnetron thermal 23. A turntable drive motor 25 is connected in parallel to the heating indoor lighting lamp 24.

A blower motor 26 for cooling the magnetron and heating coil is connected to the power source 20 via a fuse 21, a door switch 22a1, a main relay contact 71a1, a door switch 22b1, and a magnetron thermal 23.

Furthermore, the power supply 20 includes a fuse 21 and a door switch 22.
a, Main relay contact 71a1 Door switch 22b1
Inverter circuit 30 via magnetron thermal 23
is connected.

The inverter circuit 30 includes a diode bridge 31, a choke coil 32 . It has a rectifier circuit consisting of a smoothing capacitor 33, and one end of each of the primary coil 40a and heating coil 50 of the high voltage transformer 40 is connected to the output end of the rectifier circuit. Then, the other end of the secondary coil 40 is connected to one end of the resonant capacitor 34 via the normally open contact of the relay contact (bidirectional contact) 73a, and the other end of the resonant capacitor 34 is connected to the other end of the rectifier circuit. are doing. Further, the other end of the heating coil 50 is connected to one end of the resonant capacitor 34 via a normally closed relay contact 73a.

In other words, when the relay contact 73a is activated, the negative coil 4
A series resonant circuit is formed by Oa and the resonant capacitor 34. When relay contact 73a is not activated, heating coil 50 and resonant capacitor 34 form a series resonant circuit.

The resonant capacitor 34 includes a switching element such as NP.
The collector and emitter of the N-type power transistor 35 are connected in parallel, and a damper diode (flywheel) 36 is connected in parallel. Note that the power transistor 35 and damper diode 36 are packaged into one.

The power transistor 35 excites the resonant circuit by turning on and off, thereby causing the secondary coil 40a to
Alternatively, a high frequency current is caused to flow through the heating coil 50.

The anode and cathode of the magnetron 44 are connected to the secondary coil 40b of the high voltage transformer 40 via a voltage doubler rectifier circuit consisting of a high voltage capacitor 41 and high voltage diodes 42 and 43. The anode of the magnetron 44 is grounded, and the heater (cathode) is connected to the high voltage transformer 40.
is connected to the secondary coil 40c.

On the other hand, a primary coil of a step-down transformer 27 is connected to the power source 20 via a fuse 21 and a magnetron thermal 23, and a control unit 60 is connected to the secondary coil.

The control unit 60 controls the entire cooking device, and includes a power supply circuit 61, a microcomputer 62, a relay drive circuit 63, a D/A (digital/analog) converter 64, a timing circuit 65, an oscillation circuit 66, and a pulse width modulation circuit. A comparator 67 which is a circuit (PWM circuit),
It has a base drive circuit 68.

Relay drive circuit 63 drives main relay 71 and relays 72 and 73.

The D/A converter 64 issues an output setting signal of a voltage level corresponding to an output setting command from the microcomputer 62.

The timing circuit 65 connects the inverter circuit 30 to minimize loss due to switching of the inverter circuit 30.
The voltage of the smoothing capacitor 33 and the collector voltage of the power transistor 35 are taken in, and the oscillation timing of the oscillation circuit 66 is determined accordingly.

Oscillator circuit 66 generates a sawtooth signal.

The comparator 67 pulse-width modulates the sawtooth wave signal generated from the oscillation circuit 66 using the output setting signal from the D/A converter 64.

The base drive circuit 68 turns on and off the transistor 35 of the inverter circuit 30 based on the output of the comparator 67.

Thus, the operating section 4 is connected to the microcomputer 62.

Furthermore, a current transformer 80 is provided on the input line to the inverter circuit 30. This current transformer 80
constitutes input current detection means together with a bridge rectifier 81 that rectifies its output, and the output of the bridge rectifier 81 is supplied to the microcomputer 62.

Next, the operation of the above configuration will be explained with reference to FIG.

The pot 51 is placed on the top plate 3, and the tack plate key 5 of the operating section 4 is pressed. Further, a desired cooking time is set using the time setting knob 11, and a desired output is set using the up key 7 or the down key 8.

At this time, the characters "Tack plate 1" are displayed on the display 4, and the set cooking time is displayed numerically.Furthermore, on the display 4, the number of light emitting elements corresponding to the set output is lit.

When the start key 9 is pressed, the microcomputer 6
2 operates relay 71. When the relay 71 operates, the contact 71a is turned on, and an energizing path is formed to the inverter circuit 30 and the blower motor 26.

Furthermore, the microcomputer 62 issues an output setting command based on the above setting output. This output setting command is D/
The A converter 64 converts the output setting signal into an analog value output setting signal, and supplies the signal to the comparator 67.

Further, an oscillation circuit 66 generates a sawtooth wave signal, which is pulse width modulated by a comparator 67.

That is, when the voltage of the output setting signal is higher than the voltage of the sawtooth wave signal, the output voltage of the comparator 67 is at a high level.

When the voltage of the output setting signal is lower than the voltage of the sawtooth signal, the output voltage of the comparator 67 is at a low level.

The output of the comparator 67 is amplified by a base drive circuit 68 and applied between the base and emitter of the power transistor 35.

When the power transistor 35 is turned on, current flows into the heating coil 50 through the collector and emitter of the power transistor 35. When the power transistor 35 is turned off, the current flowing through the heating coil 50 begins to charge the resonant capacitor 34. Then, current flows from the resonant capacitor 34 to the heating coil 50.

In this way, a high frequency current flows through the heating coil 50 by turning on and off the power transistor 35, and a high frequency magnetic field is emitted from the heating coil 50.

The high frequency magnetic field is applied to the pot 51 through the top plate 3, causing eddy currents to be generated in the pot 51. When eddy currents occur,
The pot 51 self-heats due to eddy current loss, and the food inside is heated. In other words, this is the start of cooking.

The timing circuit 65 controls the voltage of the smoothing capacitor 33 (g
1 current voltage) and the collector voltage of the power transistor 35, a trigger pulse is generated in time with the intersection,
A trigger is applied to the oscillation circuit 66. As a result, the power transistor 35 is turned on with its own collector voltage being low, and the switching loss of the power transistor 35 can be reduced.

When the set cooking time has elapsed, the microcomputer 62
stops the operation of relay 71. When the operation of the relay 71 stops, the contact 71a turns off, and the energization path to the inverter circuit 30 is cut off. In other words, cooking is finished.

Meanwhile, place the food on the turntable inside the heating chamber and open the door 2.
At the same time, the range key 6 of the operating section 4 is pressed. Further, a desired cooking time is set using the time setting knob 11, and a desired output is set using the up key 7 or the down key 8.

At this time, the characters "range" are displayed on the display 4, and the set cooking time is displayed numerically.

Further, on the display 4, a number of light emitting elements corresponding to the set output light up.

When the start key 9 is pressed, the microcomputer 6
2 operates relays 71.72.73.

When relays 71 and 72 operate, contact 71a.

72a is turned on, and the inverter circuit 30. Heating indoor lighting lamp 24. An energizing path is formed between the turntable drive motor 25 and the blower motor 26.

When the relay 73 operates, the contact 73a switches, and the primary coil 40a of the high voltage transformer 40 and the resonant capacitor 3
4, a direct FIL resonant circuit is formed.

Thus, the inverter circuit 30 operates in the same way as electromagnetic induction heating, and a high frequency current flows through the secondary coil 40a. Then, the voltage generated in the secondary coil 40b is voltage doubled and rectified and applied to the magnetron 44, so that the magnetron 44 performs an oscillating operation. When the magnetron 44 oscillates, high-frequency radio waves are supplied into the heating chamber, and high-frequency dielectric heating starts.

When the set cooking time has elapsed, the microcomputer 62
stops the operation of relays 71, 72, 73. relay 7
When the operation of inverter 1 stops, contact 71a turns off, and the energization path to inverter circuit 30 is cut off. In other words, cooking is finished.

By the way, when the inverter circuit 30 is in operation, the input current to the inverter circuit 30 is detected by the current transformer 80, and a DC voltage at a level corresponding to the detected current is supplied from the bridge rectifier 81 to the microcomputer 62.

The microcomputer 62ci calculates the average value or actual value of the input current to the inverter circuit 30 from the output of the bridge rectifier 81, and increases the level of the output setting signal when the calculated value becomes smaller than the set value (corresponding to the set output). ,
The on period of the power transistor 35 is lengthened. vice versa,
When the calculated value becomes larger than the set value, the level of the output setting signal is lowered and the on period of the power transistor 35 is shortened.

When the on period of the power transistor 35 becomes longer, the high frequency current flowing through the heating coil 50 or the primary coil 40a becomes larger, and the output increases.

When the on period becomes shorter, the high frequency current flowing through the heating coil 50 or the primary coil 40a becomes smaller, and the output decreases.

Therefore, during electromagnetic induction heating, even if the pot 51 is different from a standard pot, the output can be maintained at the set output regardless of the difference. That is, the elements of the inverter circuit 30 are not overloaded, and the life of the elements is improved. Furthermore, proper heating is possible, and reliability can be significantly improved.

Furthermore, during high-frequency dielectric heating, the output can be maintained at the set output regardless of temperature changes in the magnetron 44.
Appropriate heating can be performed.

On the other hand, the microcomputer 62 performs cooking time setting control shown in FIG.

First, when not cooking, the display 12 displays the current time.

When high frequency dielectric heating is set by pressing the range key 6, the cooking time t is initially set to "zero minutes".

In this state, as shown in FIG. 5, the set cooking time t is increased by rotating the time setting knob 11 in the increasing direction (clockwise). When the time setting knob 11 is rotated in the decreasing direction (counterclockwise), the set cooking time t is decreased accordingly.

When electromagnetic induction heating is set by pressing the tuck plate key 7, the cooking time t is initially set to the "maximum value", for example, "95 minutes".

In this state, as shown in FIG. 6, when the time setting knob 11 is rotated in the decreasing direction, the set cooking time t
decrease. When the time setting knob 11 is rotated in the increasing direction, the set cooking time t is increased accordingly.

However, as shown in FIG. 7, when the set cooking time t is the maximum value (initial setting value) of "95 minutes", if the time setting knob 11 is rotated one click in the direction of increase from that state, the setting Switch the cooking time t to "zero minutes". After that,
As the time setting knob 11 is rotated in the increasing direction, the set cooking time t is increased to "30 seconds", "15 minutes", and so on.

Regarding the set cooking time t, regardless of the type of heating,
It is displayed sequentially on the display 12 and counts down as the cooking progresses.

In this way, when setting high-frequency dielectric heating, that is, when cooking with a relatively short cooking time, the cooking time is initially set to "zero minutes", so the desired cooking time can be easily and quickly set. be able to.

Moreover, when setting electromagnetic induction heating, that is, cooking that often takes a long time, the cooking time is initially set to the "maximum value", so you can easily and quickly set the desired cooking time. can. Only a small amount of rotation of the time setting knob 11 is required.

In particular, when setting electromagnetic induction heating, the set cooking time is set to the "maximum value" by rotating the time setting knob 11 in the increasing direction.
The next step is to switch to “zero minute”, so for example, “
This is useful when short-term electromagnetic induction heating is appropriate, such as when cooking hard-boiled eggs.

In other words, the usability is greatly improved.

In addition, regarding the operation of the time setting knob 11, the operation section 4
Since it is slanted, it is easy to operate and there are fewer errors in operation.

In addition, in the above example, the “maximum value” of the set cooking time is “
95 minutes, but there is no limit to the value and it can be determined as appropriate.

In addition, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without changing the gist.

[Effects of the Invention] As described above, according to the present invention, there is a means for initially setting the cooking time to "zero" when setting high frequency dielectric heating, and a means for setting the cooking time to "maximum value" when setting electromagnetic induction heating. A means to initialize the time, a time setting knob with an endless operation range,
Since a means for increasing/decreasing the set cooking time according to the operation of this time setting knob is provided, the operability allows easy and quick cooking time setting regardless of whether high frequency dielectric heating or electromagnetic induction heating is used. We can provide an excellent composite cooker.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a control circuit in an embodiment of the present invention, FIG. 2 is an external perspective view of the same embodiment, and FIG.
FIG. 4 is a flowchart for explaining the operation of the embodiment, and FIGS. 5 to 7 are diagrams showing the display contents of the display in the embodiment. DESCRIPTION OF SYMBOLS 1...Main body, 2...Door, 3...Top plate, 4...Operation unit, 11...Time setting knob, 12...
...Display device, 30...Inverter circuit, 40...High voltage transformer, 44...Magnetron, 50...Heating coil, 60...Control unit. Figure 2 Time - 11-ga Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (3)

[Claims] (1) In a combination cooker capable of high-frequency dielectric heating and electromagnetic induction heating, there is a means for initially setting the cooking time to "zero" when setting high-frequency dielectric heating, and a means for initially setting the cooking time to "zero" when setting electromagnetic induction heating. 1. A composite cooking device characterized by comprising means for initially setting the cooking time to a maximum value, a time setting knob having an endless operation range, and means for increasing or decreasing the set cooking time according to the operation of the time setting knob. (2) The means for increasing or decreasing the set cooking time is characterized in that when setting electromagnetic induction heating, the set cooking time is switched from "maximum value" to "zero" according to the operation of the time setting knob in the increasing direction. A composite cooking device according to claim 1. (3) The composite according to claim 1 or 2, characterized in that the time setting knob is provided on an operating section, and the operating section is provided at an angle at a corner of the cooking device main body. Cooking device.