JPH02226686A - High-frequency heating cooking apparatus - Google Patents

Abstract

PURPOSE:To shorten heating and cooking time by calculating time for a magnetron to be able to generate maximum output according to the temperature of a heat generation part, and driving the magnetron to generate maximum output up to the calculated time. CONSTITUTION:A magnetron 17 is driven via an inverter circuit 13 and a microwave outputted from the magnetron 17 is used to heat and cook a material to be cooked. The operation of the inverter circuit 13 is controled with a control circuit 19. The temperature of a heat generation part such as a switching transistor 9 and the like in the inverter circuit 13 is detected with a temperature detecting element 27 and a temperature detecting part 26. A microcomputer 22 calculates time for the magnetron 17 to be able to generate maximum output higher than normal continuous maximum output, in accordance with the detected temperature of the heat generation part at the start of operation, and drives the magnetron 17 so that maximum output higher than normal continuous maximum output can be generated from the start of operation to the calculated time.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention drives a magnetron with a high frequency inverter,
The present invention relates to a high-frequency cooking device that heats and cooks food using microwaves output from a magnetron.

(Prior Art) Some conventional heating cookers using a magnetron directly step up the input voltage from a commercial AC power source using a step-up transformer, and rectify the stepped-up output voltage to drive the magnetron. In such heating cookers, the input voltage to the step-up transformer is turned on and off in order to change the microwave output from the magnetron, and by varying the on/off ratio, the output from the magnetron can be changed. The average microwave output is varied.

In addition, other conventional heating cookers include
As shown in Japanese Patent No. 36, there is a structure in which a magnetron is driven using a frequency converter.

In this heating cooker, the microwave output from the magnetron is changed by changing the frequency of a frequency converter.

In the above-mentioned heating cooker that uses a step-up transformer, the change in the microwave output from the magnetron is an average change, whereas in the heating cooker that uses a frequency converter, the microwave output from the magnetron is approximately It can be changed as instantaneous electricity, making it superior to cooking devices that use step-up transformers. Moreover, both heating cookers can continuously heat the food to be cooked with maximum output, and can also heat the food with less output than this maximum output.

Specifically, in a heating cooker using the step-up transformer, the maximum output can be set by setting the off time of the input voltage to the step-up transformer to 0, but it is not possible to output an output higher than this maximum output. In addition, in a heating cooker that uses a frequency converter, it is theoretically possible to output a maximum output that is greater than the maximum output by varying the frequency of the frequency converter, but in this case, it is possible to A large amount of stress is applied to each element such as a switching element, a transformer, or a magnetron, and if the maximum output is continuously generated, each element will be destroyed. It is difficult to occur.

(Problems to be Solved by the Invention) Each of the conventional heating cookers described above can freely vary the microwave output below the maximum output that can be used for continuous heating. There is a problem that large microwave power cannot be generated.

The present invention has been made in view of the above circumstances, and its purpose is to provide a high-frequency heating cooker that generates a microwave output larger than the normal continuous maximum output and shortens the cooking time. It is about providing.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the high frequency cooking device of the present invention drives a magnetron via a drive circuit including an inverter, and uses microwaves output from the magnetron. A high-frequency heating cooker that cooks food by heating,
Temperature detection means for detecting the temperature of the heat generation part including the drive circuit or the magnetron, and the magnetron generates a maximum output larger than the normal continuous maximum output according to the temperature at the start of operation of the heat generation part detected by the temperature detection means. a time calculation means for calculating the possible time; and a control means for controlling the drive circuit so that the magnetron generates a maximum output that is greater than a normal continuous maximum output from the start of operation to the time calculated by the time calculation means. It is characterized by having the following.

(Function) In the high-frequency heating cooker of the present invention, the temperature at the start of operation of the heat generating part including the magnetron or its drive circuit is detected,
According to this temperature, calculate the time during which the magnetron can generate a maximum output that is higher than the normal continuous maximum output, and control the drive circuit so that the magnetron generates a maximum output that is higher than the normal continuous maximum output until this time. .

(Example) The present invention will be described in detail using the following five drawings.

FIG. 1 is a circuit diagram showing the configuration of a high frequency cooking device according to an embodiment of the present invention. The high-frequency cooking device shown in the figure operates using AC voltage from a commercial power source 1, and the AC voltage from the commercial power source 1 is applied to a door switch 2a that is closed by closing the door of the high-frequency cooking device. , 2b and the relay contact 3 to the fan motor 4 and the rectifier bridge 5 of the rectifier circuit 8, where it is rectified.

A fan (not shown) is attached to the fan motor 4,
This fan cools the switching transistor 9, high frequency transformer 12, magnetron 17, etc. of the inverter circuit 13, which will be described later.

The rectifier bridge 5 of the rectifier circuit 8 rectifies the AC voltage from the commercial power supply 1 and converts it into a DC voltage, smoothes this DC voltage with a choke coil 6 and a smoothing capacitor 7, and supplies the smoothed DC voltage to the inverter circuit 13.

The inverter circuit 13 is composed of a primary coil 12a1 of a high frequency transformer 12, a switching transistor 9 connected in series to this primary coil 12a, a regenerative current diode 10 and a resonance capacitor 11 connected in parallel to this switching transistor 9, and rectifier. A high output voltage is generated in the secondary coil 12b of the high frequency transformer 12 by cutting off the primary current (2) flowing from the circuit 8 to the primary coil 12a of the high frequency transformer 12 by the switching transistor 9.

The high output voltage generated in the secondary coil 12b of the high frequency transformer 12 by the intermittent operation of the switching transistor 9 in the inverter circuit 13 is transferred to the half-wave voltage doubler rectifier circuit 16.
The voltage is then boosted to double the voltage.

The half-wave voltage doubler rectifier circuit 16 is composed of a secondary coil 12b of the high-frequency transformer 12, a voltage doubler capacitor 14, and a voltage doubler diode 15.
The boosted voltage is applied between the anode and cathode of the magnetron 17, and the voltage generated in the tertiary coil 12c of the high frequency transformer 12 is applied to the filament of the magnetron 17, thereby driving the magnetron 17. , outputs microwaves.

Further, the AC voltage from the commercial power supply 1 is converted to a predetermined voltage via a transformer 18 and supplied to a control circuit 19, and then rectified to a predetermined DC voltage by a rectifier circuit (not shown) or the like.
It is supplied to each part of the control circuit 19 as an operating voltage of the control circuit 19.

The control circuit 19 includes a microcomputer 22, a clock oscillator 23 that generates an operating reference clock supplied to the microcomputer 22, and a relay drive unit that controls opening and closing of the relay contacts 3 based on command signals from the microcomputer 22. 21 and microcomputer 2
an output setting section 24 whose microwave output value is set by a command signal from 2; and the output setting section 24 is supplied with the set microwave setting value, and controls the switching of the switching transistor 9 according to this setting value. P
It is composed of a WM section 25.

Further, an input signal is supplied to the microcomputer 22 from the operation section 20, and the microcomputer 22 operates in accordance with this input signal.

Further, a temperature detection element 27 is provided near the switching transistor 9 of the inverter circuit 13, and the resistance value of this temperature detection element 27 changes in accordance with the temperature of heat generated from the switching transistor 9. This change in resistance is detected by the temperature detection section 26 and converted into temperature information, and the detected temperature from the temperature detection section 26 is supplied to the microcomputer 22.

The high frequency heating cooking device constructed as above will be explained with reference to FIGS. 2 and 3. Furthermore, Fig. 2 shows the waveforms of various parts when the high-frequency heating cooker shown in Fig. 1 is operated at the normal continuous maximum output, and Fig. 3 shows the waveforms of each part when operating the high-frequency cooking device shown in Fig. 1 at the maximum continuous output. It is a figure which shows the waveform of each part when a high frequency heating cooking device is operated so that output may be generated.

The PWM section 25 of the control circuit 19 is connected to the microcomputer 2.
2 supplies the switching transistor 9 of the inverter circuit 13 with an on signal corresponding to a time corresponding to the setting value set in the output setting section 24 by the inverter circuit 2 . This PWM section 25
As shown in FIG. 2(f), the ON signal supplied to the switching transistor 9 from the time to is 1. When this ON signal is supplied to the switching transistor 9, the switching transistor 9 is in the ON state during this ON signal. When the switching transistor 9 is turned on, the current 11 flows through the switching transistor 9 from time to time so that it gradually increases according to the inductance of the high-frequency transformer 12 via the primary coil 12a of the high-frequency transformer 12, as shown in FIG. 2(a). to tl, and a current I2 as shown in FIG. 2(C) also flows through the high frequency transformer 12.
The current flows gradually upward into the primary coil 12a. In this way, when the switching transistor 9 is on, the collector-emitter voltage Vce of the switching transistor 9 is a very small voltage as shown in FIG. 2(b).

Furthermore, in this case, the secondary coil 12 of the high frequency transformer 12
A secondary current 3 and a magnetron current I4 shown in FIGS. 2(d) and 2(e) flow through the magnetron 17 and the magnetron 17, respectively, and the magnetron 17 is driven by the magnetron current 14 to generate microwaves. Of the secondary current I3 flowing through the secondary coil 12b of the high-frequency transformer 12, a positive current flows to the magnetron 17 as an anode current, and the other negative current is used for voltage doubler of the half-wave voltage doubler rectifier circuit 16. A charging current flows to the voltage doubler capacitor 14 via the diode 15, and the voltage charged in the voltage doubler capacitor 14 is added to the positive voltage of the next cycle, and the double voltage is applied to the magnetron 17. It looks like this.

During the on time ton from time to to tl, the same current as the current flowing through the primary coil 12a of the high frequency transformer 12 flows through the switching transistor 9, but when the on signal disappears at time t1, the switching transistor 9 The transistor 9 is turned off, and the current I flowing through the switching transistor 9 becomes zero as shown in FIG. 2(a).

After the switching transistor 9 is turned off, the current I2 flowing through the primary coil 12a of the high frequency transformer 12
is time 1 in FIG. 2(c). As shown below, the current flows to the resonant capacitor 11 and enters a resonant state, thereby charging the resonant capacitor 11 and increasing the voltage of the resonant capacitor 11, that is, the collector-emitter voltage Vce of the switching transistor 9, as shown in FIG. ). In this resonant state, the collector-emitter voltage Vce reaches its highest level at the time when the direction of the current I2 flowing through the primary coil 12a of the high-frequency transformer 12 is reversed, and thereafter this voltage Vce decreases at time t2.
At this point, the voltage Vce becomes O. In this way, the voltage Vce
At time t2 when becomes 0, the current flowing through the primary coil 12a of the high frequency transformer 12! 2 does not flow to the resonance capacitor 11, but flows through the regenerative current diode 10 as the current 11, and 1. -It becomes I2.

At time t3, which is delayed by a predetermined time from time t2, PWM
The on signal is generated again from the section 25 and is supplied to the switching transistor 9, so that the switching transistor 9 is turned on variably. When the switching transistor 9 is turned on, the current I2 flowing through the primary coil 12a of the high frequency transformer 12 becomes positive again from time t4 to the current 1.
1 will now flow through the switching transistor 9 instead of through the regenerative current diode 10. Thereafter, similarly, the on-time to when the switching transistor 9 is on is
During the period n, currents 11 and I2 flow through the switching transistor 9 and the primary coil 12a of the high-frequency transformer 12, respectively, so as to gradually rise with a slope according to the inductance of the high-frequency transformer 12, and after the on-time ton, the currents enter the resonant state again. This operation is repeated, and as a result, a magnetron current 4 as shown in FIG. 2(e) flows through the magnetron 17, which causes the magnetron 1 to
7 is driven to generate microwaves.

Here, when the microcomputer 22 sets a setting value corresponding to an on time smaller than the on time ton shown in FIG. 2 in the output setting section 24, the current flowing through the switching transistor 9 is 11% The primary current ■2 flowing through the primary coil 12a of the high-frequency transformer 12, the secondary current I3 flowing through the secondary coil 12b of the high-frequency transformer 12, and the magnetron current ■4 flowing through the magnetron 17 all have small current values in proportion to the set values. Become. That is, by varying the on-time ton for driving the switching transistor 9, the microwave output from the magnetron 17 can be varied to an arbitrary value.

FIG. 3 is a diagram showing operating waveforms of various parts corresponding to FIG. 2 during overdrive, which produces an instantaneous maximum output larger than the maximum output during continuous operation shown in FIG. 2.

In Figure 3, an overdrive state is formed and the magnetron outputs an instantaneous maximum output that is greater than the continuous maximum output in Figure 2.
7, the on-time ton shown in FIG.
The on-time ton is set to be longer than that. As a result,
Current waveform I at each part in Figure 3! 2, I3, and I4, as can be seen by comparing them with the corresponding current waveforms of each part in FIG.
After the on-time ton ends, the switching transistor 9
They are all loud and overdriven at the point when they turn off. Therefore, the magnetron 17 outputs microwaves with a maximum output larger than the continuous maximum output shown in FIG.

In addition, in this overdrive state, the current ■1 flowing through the switching transistor 9 increases, and the collector-emitter voltage Vce of the switching transistor 9 also increases, so the heat generated from the switching transistor 9 increases accordingly, and it continues as it is. If the overdrive state continues, the switching transistor 9 will be destroyed. Similarly, since the current flowing through the high frequency transformer 12 and magnetron 17 is also large,
The heat generated from the high frequency transformer 12 and the magnetron 17 also increases accordingly, and if the overdriven state continues as it is, the high frequency transformer 12 and the magnetron 17 will be damaged.

By the way, destruction and damage of each element such as the switching transistor 9, high frequency transformer 12, and magnetron 17 due to overdrive occurs due to temperature rise due to heat generation due to current and voltage in each element. It does not occur instantaneously, but it starts operating in an overdrive state and the temperature of each element gradually increases.
The breakdown temperature is reached, and it takes a certain amount of time from the start of operation until the breakdown temperature is reached.

More specifically, this will be explained with reference to FIG.

FIG. 4(a) is a graph in which the horizontal axis shows the operating time of the high-frequency cooking device shown in FIG. 1, and the vertical axis shows the temperature of the switching transistor 9 detected by the temperature detection element 27.
In FIGS. 4(b) to 4(d), the horizontal axis shows time taken corresponding to the time on the horizontal axis in FIG. 4(a), and the vertical axis shows the output level from the magnetron 17.

When the high-frequency heating cooker shown in FIG. 1 is operated at the continuous maximum output shown in FIG. 2, when the operation is started from time t10, as shown by curve A in FIG. 4(a), The temperature of the switching transistor 9, which was at the initial temperature T1 at the operation start time t10, gradually rises and reaches the saturation temperature T3 at the time t12, and even if the operation is continued, the temperature of the switching transistor 9 does not rise above the saturation temperature. Therefore, the switching transistor 9 can continue to operate continuously without being destroyed. In this normal continuous state, as shown in FIG.
Even if continuous maximum output of 0.00 watts is output continuously, it will not be destroyed.

On the other hand, if the high-frequency cooking device is operated in the overdrive state shown in Figure 3 by generating a maximum continuous output that is higher than the maximum continuous output in the normal continuous state, curve B in Figure 4 (a) As shown, the temperature of the switching transistor 9 is curve A
It rises more rapidly than in the case of , and the switching transistor 9
If the temperature does not break down, it should rise to temperature T6 and become saturated, but this shows that it breaks down at time t12 when the breakdown temperature T5, which is lower than the saturation temperature T6, is reached.

As shown in FIG. 4(d), this overdrive state occurs when the high-frequency heating cooker has a power output of 700, which is higher than the continuous maximum output.
The maximum output of watts is generated and breakdown occurs at time t12.

Further, a curve C shown in FIG. 4(a) indicates that the temperature of the switching transistor 9 is the saturation temperature T3 at the time of the continuous maximum output.
Time t11 at which the predetermined safe temperature T2 is reached, which is slightly lower than
Until then, the high-frequency heating cooker is operated in an overdrive state to generate maximum output, and the high-frequency cooking device is operated in an overdrive state to generate the maximum output, and the predetermined overdrive safety temperature T2 is reached.
After time t11, the output is reduced to the continuous maximum output and the operation is performed. By operating in this manner, the temperature of the switching transistor 9 will eventually be saturated at the saturation temperature T3 at the time of continuous maximum output, and the switching transistor 9 will not be destroyed.

FIG. 4(b) shows the output state of the high-frequency heating cooker in this case. During the period from time t+o to t11, the maximum output in an overdrive state of, for example, 700 watts is generated, and at time t After I+, a continuous maximum output of, for example, 500 watts is generated.

By the way, in actual usage conditions, the high-frequency heating cooker may be operated multiple times in succession, or the operating environment temperature may be low or high, and in these cases, the initial Although the temperature T1 varies, the duration of the overdrive state that can generate the instantaneous maximum output also varies depending on the initial temperature T1. For example, if the initial temperature T1 at the start of device operation is low, if the overdrive state occurs and the instantaneous maximum output is generated, the time required for the temperature of the switching transistor 9 to reach the overdrive safety temperature T2, that is, the instantaneous maximum output is generated. The duration of the overdrive state obtained becomes longer, and when the initial temperature T is high, the time until the temperature of the switching transistor 9 reaches the overdrive safety temperature T2, that is, the duration of the overdrive state that can generate the instantaneous maximum output increases. Time is getting shorter.

Specifically, this will be explained with reference to FIG. Figure 5(a)~
In each figure (f), the horizontal axis shows the operating time of the device, the vertical axis shows the temperature of the switching transistor 9 (a) to (C) in Fig. 5, and (d) to (f') show the temperature of the switching transistor 9. The output level from 17 is shown. Also, (a) and (d) in Fig. 5 correspond, (b) and (e) correspond, and (
c) and (r) correspond.

FIGS. 5(a) and 5(d) are diagrams in the case where the initial temperature of the switching transistor 9 at the start of device operation is T1, and the device is put into an overdrive state from the start of device operation to generate the instantaneous maximum output. . As shown in FIG. 5A, the temperature of the switching transistor 9 gradually rises from the initial temperature T1, and the overdrive state is stopped at time t25 when the temperature of the switching transistor 9 reaches the overdrive safety temperature T2. This is the case where the overdrive state is reduced to the normal continuous maximum output, and the duration of the overdrive state in which the instantaneous maximum output is generated until the overdrive safety temperature T2 is reached is from time to to t25.

In addition, FIGS. 5(b) and 5(e) show the initial temperature T1, which is higher than the initial temperature T1. In this case, the temperature of the transistor 9 reaches the overdrive safety temperature T2 at time t23, and the duration of the overdrive state that generates the instantaneous maximum output is from time to to t23 when the initial temperature T1. It is shorter than .

Furthermore, FIGS. 5(c) and (f') show that the initial temperature is higher than T.
1. In this case, the temperature of the switching transistor 9 reaches the overdrive safety temperature T2 at time t2□, and the duration of the overdrive state where the instantaneous maximum output is reached is from time to
It became even shorter from t21 to t21.

In either case shown in FIG. 5, the temperature of the switching transistor 9 is almost the same at the time when the instantaneous maximum output is generated in the overdrive state and then switched to the normal continuous maximum output, and each element is without destroying it,
In each case, it is possible to generate the instantaneous maximum output and operate in an overdrive state, but the duration of the overdrive state that can generate the instantaneous maximum output varies depending on the initial temperature, and the maximum instantaneous output is It can be seen that the duration of the possible overdrive condition depends on the initial temperature.

As described above, the present invention focuses on the initial temperature of each element at the start of device operation, measures this initial temperature, and calculates the duration of the overdrive state that can generate instantaneous maximum output according to the measured initial temperature. is calculated, and the overdrive state is set only during the calculated duration time to generate the instantaneous maximum output.

FIG. 6 is a flowchart showing the operation of this embodiment. The operation will be explained with reference to FIG. first,
When the temperature detection element 27 detects the initial temperature of the switching transistor 9 at the start of heating the device (step 110), it is checked whether this detected initial temperature is lower than the initial temperature T1 shown in FIG. 5 described above (step 120).
). If the detected initial temperature is below temperature T1, the duration of the overdrive state that can generate the instantaneous maximum output is set to t25 (step 130), and the overdrive state is maintained until this set time to generate the instantaneous maximum output. After that, switch to the normal continuous maximum output.

Further, when the detected initial temperature is higher than temperature T1, the detected initial temperature is temperature T1. Check whether it is less than or equal to (step 140). If the temperature is below T1°,
The duration of the overdrive state that can generate the instantaneous maximum output is t
23 (step 150), the cooking is performed by generating instantaneous maximum output in the overdrive state until this set time, and thereafter switching to the normal continuous maximum output.

Similarly, the detected initial temperature is the temperature T1. If the detected initial temperature is higher than temperature T1. It is checked whether the value is less than or equal to (step 160). Temperature T1. In the following cases, the duration of the overdrive state that can generate the instantaneous maximum output is set to t2□ (Step 170), the overdrive state is maintained until this set time, the instantaneous maximum output is generated, and cooking is performed, After that, switch to normal continuous maximum output. Furthermore, the detected initial temperature is temperature T1. , the duration of the overdrive state that can generate instantaneous maximum output is 0.
, and the cooking operation is performed using only the normal continuous maximum output (step 180).

Furthermore, FIG. 7 is a flowchart showing another operation of this embodiment. In the figure, in step 210, the temperature of the switching transistor 9 is detected by the temperature detection element 27.
), if this detected temperature is below the predetermined temperature T4 mentioned above, the heating operation is continued (steps 220, 230), but if it is higher than the predetermined temperature T4, the heating is stopped (step 240). Through this process, even if the fan motor 4 breaks down and each element in the device becomes high temperature, the temperature detection element 27 detects this temperature, and when the detected temperature reaches the predetermined temperature 14 or higher, The heating operation of this high-frequency cooking device is stopped to prevent each element from being destroyed. In this way, the temperature detection element 27 not only detects the initial temperature for calculating the duration of the overdrive state that can generate the instantaneous maximum output, but also detects abnormal conditions when a part of the high-frequency heating cooker malfunctions. It also has the function of detecting temperature rises, increasing the safety of the device.

As explained above, in this embodiment, the duration of the overdrive state that can generate instantaneous maximum output is determined based on the initial temperature at the start of operation of the device, but this By calculating the duration of the overdrive state that can generate instantaneous maximum output when the user is about to start using the system, and displaying this calculated time on a display, for example, to clearly show the user. , it is possible to grasp the shortened cooking time due to the instantaneous maximum output due to the overdrive state.

Specifically, for example, if there is a cooking that requires heating at 500 watts for 3 minutes, and in this case the instantaneous maximum output time of 700 watts is displayed as 4 minutes, the user would
It was found that cooking could be done with only the instantaneous maximum output of 0 watts, and as a result, the heating time was set to 2.14.
It turns out that it is sufficient to set the number of minutes, that is, 3×500/700=2.14 minutes.

Similarly, in the case of cooking that requires heating at 500 watts for 3 minutes, if the instantaneous maximum output time is displayed as 1 minute 30 seconds, the heating time is 2.4 minutes, that is (3X500
It can be seen that the setting should be -1.5×700)÷500+1.5=2.4 minutes.

In the above embodiment, as shown in FIG. 6, the initial temperature at the start of operation is divided into three stages, but the invention is not limited to this and may be further divided into a plurality of stages. Of course, it is also possible to change the value continuously using a mathematical formula.

Further, in the above embodiment, the temperature of the switching transistor 9 is detected and controlled, but the temperature is not limited to this, and the temperature of the high frequency transformer 12 and magnetron 17 is also detected to perform similar control. The same effect can be achieved by detecting multiple temperatures of each part at the same time, and determining the duration of the overdrive state that can generate instantaneous maximum output based on the multiple detected temperatures. Good too.

[As described in the detailed description of the invention, according to the present invention, the temperature at the start of operation of the magnetron or the heat generating part including its drive circuit is detected, and according to the detected temperature, the magnetron outputs more than the normal continuous maximum output. The time during which a large maximum output can be generated is calculated, and the drive circuit is controlled so that the magnetron generates a maximum output larger than normal continuous maximum output until this time. It is possible to shorten the heating cooking time, and also to calculate the duration of time during which the instantaneous maximum output can be generated at the start of the device operation.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a high-frequency heating cooker according to an embodiment of the present invention, and FIG. 2 is an operation waveform diagram of each part when the high-frequency heating cooker of FIG. 1 generates the maximum output during continuous operation. Third
The figure shows the operating waveforms of each part when the high-frequency cooking device shown in Fig. 1 generates the instantaneous maximum output. 6 and 7 are flowcharts showing the operation of the high frequency cooking device of FIG. 1. 9... Switching transistor, 12... High frequency transformer, 13... Inverter circuit, 17... Magnetron, 19... Control circuit, 24... Output setting section, 25... PWM section, 26 ...Temperature detection section, 27...Temperature detection element. “Yo”! 1st category 1st Physician Hidekazu Miyoshi Figure 1 Figure 5 Figure 4r! ! j Figure 6 Figure 7

Claims (2)

[Claims] (1) A high-frequency cooking device that drives a magnetron via a drive circuit consisting of an inverter and heats and cooks food using microwaves output from the magnetron, and the temperature of the heat generating part including the drive circuit or the magnetron. temperature detection means for detecting; and time calculation means for calculating the time during which the magnetron can generate a maximum output larger than the normal continuous maximum output according to the temperature at the start of operation of the heat generating part detected by the temperature detection means; and a control means for controlling the drive circuit so that the magnetron generates a maximum output that is higher than a normal continuous maximum output from the start of operation to the time calculated by the time calculation means. . (2) Claim (1) further comprising a stop means for stopping the operation of the drive circuit when the temperature of the heat generating part detected by the temperature detecting means exceeds a predetermined temperature.
High frequency heating cooker as described.