JPH0942674A - Cooker - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To make the rotation speed of a fan motor constant without being affected by a decrease in viscosity of grease contained in a sintered metal. A microwave oven is provided with a fan device and a heater, and after the air discharged from the fan device is blown to the heater to turn it into hot air, oven cooking is performed by supplying the air to the cooking chamber. In the case of this configuration, when the grease contained in the sintered metal is heated with the progress of cooking in the oven, the viscosity of the grease decreases. Therefore, as the conduction angle of the fan motor is reduced with the progress of oven cooking, the amount of voltage applied to the fan motor is reduced and the rotation speed of the fan motor is kept constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating cooker configured to control a phase of a fan motor for supplying hot air.

[0002]

For example, some microwave ovens have a hot air circulation type oven function. This microwave oven is configured to generate hot air by blowing air from the fan device to the heater and supply the hot air to the cooking chamber to perform oven cooking. In the case of this configuration, the motor drive circuit mainly composed of the triac controls the phase of the fan motor of the fan device, and the conduction angle of the fan motor is kept constant by giving the pulse signal to the triac at a constant phase angle. Hold on.

However, in the above-mentioned conventional structure, since the rotating shaft of the fan motor is supported by the sintered metal,
When the sintered metal is heated with the operation of the fan motor,
The viscosity of the grease contained in the sintered metal becomes smaller,
The fan motor speed increases. Therefore, the amount of hot air supplied to the cooking chamber may vary, and the finished state of the cooked product may be uneven.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a heating cooker in which the rotation speed of a fan motor can be made constant without being affected by heat generated by the operation of the fan motor. That is.

[0005]

A cooking device according to claim 1 is a fan device comprising a fan motor having a rotary shaft supported by a sintered oil-impregnated bearing, and a fan rotating when the fan motor is driven. A heat source for heating the air discharged from the fan device to generate hot air for heating and cooking, and a motor control means for phase-controlling the fan motor of the fan device. The feature is that the rotation speed of the fan motor is made substantially constant as the conduction angle of the fan motor is reduced in accordance with the above. According to the above means, the conduction angle of the fan motor becomes smaller as the heating and cooking time elapses, so that the viscosity of the grease contained in the sintered oil-impregnated bearing decreases (the rotation resistance of the fan motor decreases). The amount of voltage applied to is reduced. For this reason, the rotation speed of the fan motor is made substantially constant, so that the amount of hot air supplied into the cooking chamber is also made constant, and as a result, the finished state of the cooked product is made uniform.

A heating cooker according to a second aspect of the invention is provided with a clocking means for performing an adding operation with the passage of time at the time of heating and a subtracting operation with the passage of time at the end of the heating and the motor control means is provided. It is characterized in that the conduction angle of the fan motor is changed according to the time measurement result of the time measurement means. According to the above means, when the cooking is finished, the time counting result added during cooking is subtracted as time passes, and when the next cooking is performed, the subtracted time counting result is used as an initial value for the fan motor. The conduction angle of is adjusted. Therefore, the conduction angle can be adjusted with the viscosity of the grease improved during non-cooking as the initial value, so that the rotation speed of the fan motor is reliably made constant.

A cooking device according to a third aspect of the present invention includes a voltage detecting means for detecting a power supply voltage of the fan motor, and the motor control means corrects the conduction angle of the fan motor according to the detection result of the voltage detecting means. However, it has a feature. According to the above means, when the power supply voltage of the fan motor is detected, the conduction angle of the fan motor is corrected according to the magnitude of the power supply voltage. Therefore, the fan motor rotates at a constant speed regardless of the magnitude of the power supply voltage.

According to another aspect of the present invention, there is provided a heating cooker including temperature setting means for setting the temperature inside the cooking chamber, and the motor control means sets the conduction angle of the fan motor in accordance with the value set by the temperature setting means. The feature is that it corrects. According to the above means, when the temperature inside the cooking chamber is set, the conduction angle of the fan motor is corrected according to the set value of the temperature inside the cooking chamber. In this case, the rising state of the heat source, that is, the grease viscosity reduction rate is determined according to the set value of the internal temperature, so that the fan motor rotates at a constant speed without being affected by the grease viscosity reduction rate.

According to the fifth aspect of the present invention, there is provided a heating cooker comprising a fan motor having a rotary shaft supported by a sintered oil-impregnated bearing, a fan device rotating with the driving of the fan motor, and a discharge device from the fan device. A heat source that heats the generated wind to generate hot air for heating and cooking, a motor control unit that controls the phase of the fan motor of the fan device, and a temperature detection unit that detects the temperature inside the cooking chamber. The motor control means is characterized in that the rotation speed of the fan motor is made substantially constant as the conduction angle of the fan motor is reduced as the temperature detected by the temperature detection means increases. According to the above means, the conduction angle of the fan motor becomes smaller as the temperature inside the chamber becomes higher. Therefore, the amount of voltage applied to the fan motor becomes smaller as the viscosity of the grease contained in the sintered oil-impregnated bearing decreases. .
For this reason, the rotation speed of the fan motor is made substantially constant, so that the amount of hot air supplied into the cooking chamber is also made constant, and as a result, the finished state of the cooked product is made uniform.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will now be described with reference to FIG.
A description will be given with reference to FIG. In this embodiment, the present invention is applied to a microwave oven having a hot air circulation type oven function. First, in FIG. 3, a cooking chamber 2 is formed inside the microwave oven main body 1. A door 3 is pivotally supported on the microwave oven main body 1, and the front opening of the cooking chamber 2 is opened and closed by the door 3.

As shown in FIG. 4, a magnetron 4 is arranged in the microwave oven main body 1. Then, when the magnetron 4 is operated, microwaves are radiated into the cooking chamber 2 through a waveguide (not shown) to perform range cooking. A rotary shaft projects into the cooking chamber 2, and when performing range cooking, a turntable is attached to the rotary shaft, and food is placed on the turntable.

At the back of the cooking chamber 2, as shown in FIG.
A hot air generating chamber 5 is formed, and an annular heater 6 corresponding to a heat source and a fan 7 of a fan device 7 are formed in the hot air generating chamber 5.
a is provided. The fan device 7 is composed of a fan 7a and a fan motor 7b. When the fan motor 7b operates and the fan 7a rotates, wind is blown to the annular heater 6 to generate hot air for oven cooking. The fan motor 7b is a bear removing motor, and the fan 7a is a centrifugal fan. The rotating shaft of the fan motor 7b is supported by sintered metal corresponding to a sintered oil-impregnated bearing.

Discharge ports 2a, 2a are formed in the upper and lower parts of the back wall of the cooking chamber 2, and the suction port 2 is located in the central part.
b is formed. Then, the hot air generated by the annular heater 6 is supplied into the cooking chamber 2 from both the discharge ports 2a as shown by the arrow, and then the hot air generating chamber 5 from the suction port 2b.
Returned inside. As a result, hot air circulates in the cooking chamber 2 and the food contained in the cooking chamber 2 is oven-cooked. When performing oven cooking, the shelf 8 is mounted in the cooking chamber 2 and the food is placed on the shelf 8.

As shown in FIG. 4, a control device 9 corresponding to motor control means is provided in the microwave oven main body 1. The control device 9 is mainly composed of a microcomputer, and the magnetron 4 is connected to the control device 9 via a magnetron drive circuit 4a.

An operation panel 1 is provided on the front of the microwave oven body 1.
0 is provided, and the operation panel 10 is provided with a cooking mode selection key 10a, a start key 10b, a temperature setting key 10c corresponding to temperature setting means, and the like. And
Each key 10a-10c is connected to the control device 9,
When the control device 9 detects that range cooking has been selected based on the operation content of the cooking mode selection key 10a, the magnetron drive circuit 4 is operated in accordance with the operation of the start key 10b.
The magnetron 4 is actuated via a to perform range cooking.

A motor drive circuit 11 is connected to the control device 9. The motor drive circuit 11 is mainly composed of a triac (not shown), and the fan motor 7b of the fan device 7 is connected to the motor drive circuit 11. Then, when the control device 9 detects that the oven cooking is selected based on the operation content of the cooking mode selection key 10a, the pulse signal shown in FIG. Give to the gate terminal. Then, the triac is turned on from the phase angle at which the pulse signal is given to the next zero cross point, and a sawtooth voltage is applied to the fan motor 7b as shown in FIG. Controlled.

As shown in FIG. 4, the cooking chamber 2 is provided with a temperature sensor 12 corresponding to a temperature detecting means. This temperature sensor is composed of a thermistor and is connected to the control device 9. Then, the control device 9 detects the internal temperature T of the cooking chamber 2 based on the output signal from the temperature sensor 12, and the heater 6 is held so that the internal temperature T is maintained at the temperature set by the temperature setting key 10c. Control on and off. Reference numeral 6a represents a heater drive circuit.

The ROM of the control device 9 stores an arithmetic expression for adjusting the conduction angle (conduction angle) of the triac. This calculation formula is the conduction angle (rad) of the triac.
1 is a functionalized version of the experimental data of FIG. 1 showing the relationship between the cooking time and the oven cooking time (t). When the oven cooking is started, the control device 9 assigns the cooking time to the arithmetic expression to give it to the triac. The phase angle of the pulse signal is changed to adjust the conduction angle of the triac.

Next, the operation of the above configuration will be described. When the control device 9 detects that the cooking mode selection key 10a has selected the oven cooking and the temperature setting key 10c has set the internal temperature, the start key 10b.
In accordance with the above operation, the fan motor 7b and the heater 6 are turned on to supply hot air into the cooking chamber 2. Then, the supply timing of the pulse signal is calculated based on the cooking time, and the energization angle of the fan motor 7b is reduced as the cooking time elapses.

For example, when the cooking time exceeds 60 minutes, in the first half of cooking (time 0-t1 in FIG. 1), the fan motor 7b is used.
The grease contained in the sintered metal is heated by the heat generated by the operation of, and the viscosity of the grease gradually decreases. Therefore, since the rotation resistance of the fan motor 7b decreases, the control device 9 gradually decreases the conduction angle from "π" to "π / 2" (the phase angle of the pulse signal is "0" as the cooking time elapses. From ”to“ π / 2 ”). Then, the amount of voltage applied to the fan motor 7b is reduced as the viscosity of the grease decreases, and the fan motor 7b
b rotates at a constant speed.

In the latter half of the cooking (time t1-t2), the grease contained in the sintered metal is sufficiently heated, and the viscosity of the grease becomes a constant low value. Therefore, the control device 9
Is a constant low value "π / 2" for the energization angle of the fan motor 7b.
(The phase angle of the pulse signal is set to “π / 2”). As a result, the amount of voltage applied to the fan motor 7b becomes constant according to the viscosity of the grease, and the fan motor 7b rotates at a constant speed.

According to the above-described embodiment, since the energization angle of the fan motor 7b is reduced with the elapse of the cooking time t, the viscosity change of the grease contained in the sintered metal (the reduction of the rotation resistance of the fan motor 7b). Accordingly, the amount of voltage applied to the fan motor 7b decreases. Therefore, the rotation speed of the fan motor 7b is made constant, so that the amount of hot air supplied into the cooking chamber 2 is also made constant, and as a result, the finished state of the cooked food is made uniform.

Next, a second embodiment of the present invention will be described with reference to FIG. The same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Hereinafter, only different members will be described. When starting the oven cooking, the control device 9 adds "1" to the value N of the counter (corresponding to the time measuring means) every 1 minute, and judges "N = 60?". When "N <60" (time 0 -t
In 1), the phase angle of the pulse signal is increased by “(1/60 × π / 2)” each time “1” is added to N, and the conduction angle of the triac is increased by “(1/60 × π / 2)”. ) "

When the controller 9 detects "N = 60" at the time t1, it stops the adding operation of the counter. Then, until the fan motor 7b and the heater 6 are turned off and the oven cooking is finished (time t1 to t2), a pulse signal is given at a constant low phase angle “π / 2” to set the conduction angle of the triac to a constant low value. Maintain at “π / 2”.

When the oven 9 finishes cooking at time t2, the controller 9 sets the counter value N to "6" every one minute.
Subtract "1" from "0" (time t2-t3). And
Each time N is subtracted by "1", the phase angle of the pulse signal is changed to "(1 /
60 × π / 2) ”, and the phase angle is sequentially rewritten as the non-oven cooking time elapses. The broken line in (a) is the energization angle corresponding to the count value N during non-oven cooking.

When the oven 9 restarts cooking while rewriting the phase angle (time t3), the controller 9 gives a pulse signal to the triac with the latest phase angle as an initial value. Then, while "N <60" (time t3 to t4), N
Each time "1" is added to, the phase angle becomes "(1/60 × π /
2) ”in increments, and the conduction angle of the triac is increased to“ (1 /
60 × π / 2) ”.

When the oven 9 finishes cooking at time t4, the controller 9 subtracts "1" from the count value N at the end of cooking every one minute (time t4-t5). Then, every time “1” is subtracted from the count value N, the phase angle of the pulse signal is decreased by “(1/60 × π / 2)”, and the phase angle is set to “0” as the non-oven cooking time elapses. Rewrite sequentially until.

When the count value N is subtracted to "0" at time t5, the control device 9 stops the counter subtraction operation (time t5-t6). Then, when the oven cooking is restarted at time t6, a pulse signal is given to the triac with the phase angle “0” as an initial value, and the phase angle is “(1/60 × π / 2)” every time “1” is added to N. ”Increments, and the conduction angle of the triac is increased to“ (1 /
60 × π / 2) ”. Each operation described above is performed based on the software configuration of the control device 9.

According to the above-described embodiment, the count value N added during the oven cooking is subtracted as the non-oven cooking time elapses, and when the oven cooking is restarted, the subtracted count value N is set as the initial value of the triac. The conduction angle was adjusted. Therefore, when the oven cooking is restarted, the conduction angle is adjusted with the viscosity of the grease improved during the non-oven cooking as an initial value, so that the rotation speed of the fan motor 7b is reliably kept constant. As a result, the amount of hot air supplied to the cooking chamber 2 is surely made uniform, so that the finished state of the cooked product is further improved.

Next, a third embodiment of the present invention will be described with reference to FIG. The same members as those in the second embodiment are denoted by the same reference numerals, and description thereof will be omitted. Hereinafter, only different members will be described. When starting the oven cooking, the controller 9 corresponding to the voltage detecting means starts the fan motor 7b.
The A / D conversion result of the power supply voltage V is sampled and the magnitude of the power supply voltage V is detected by detecting the peak value of the sampling data.

For example, when the power supply voltage V is "V≤90VOLT", the control device 9 controls the time 0a as shown by the solid line α.
The counter does not perform the addition operation up to and the conduction angle of the triac is maintained at "π". And from time 0a to t1a
Until 0, the counter is added with the initial value "0", and the conduction angle of the triac is calculated as "(1/60 × π /
2) ”each smaller.

The controller 9 stops the addition operation when "N = 60" is reached at the time t1a, and keeps the conduction angle of the triac at a constant low value "π" until the oven cooking is finished at the time t2.
/ 2 ". After that, the subtraction operation of the counter is performed from t2 to time t2a, and the phase angle of the pulse signal is sequentially rewritten until it reaches "0". Therefore, when the oven cooking is next performed, the control device 9 adds the count value N with "0" as the initial value. The broken line α in (a) is the energization angle corresponding to the count value N during non-oven cooking.

Further, the power supply voltage V is "90VOLT <V≤10.
When it is “0VOLT”, the control device 9 performs the addition operation of the counter from time 0 to t1 with “0” as the initial value, as shown by the solid line β, and sets the conduction angle of the triac to “(1
/ 60 × π / 2) ”.

The controller 9 stops the addition operation when "N = 60" is reached at time t1. Then, the conduction angle of the triac is maintained at a constant low value “π / 2” until the oven cooking is finished at time t2. After this, the counter is subtracted from time t2 to t2a, and the phase angle is rewritten in sequence until it reaches "0". Therefore, when the oven cooking is next performed, the control device 9 adds the count value N with "0" as the initial value. The broken line β in (a)
Is an energization angle corresponding to the count value N during non-oven cooking.

Further, the power supply voltage V is "100VOLT <V≤1.
10VOLT ”, the control device 9 performs the counter addition operation with Na (> 0) as the initial value, as shown by the solid line γ, and changes the conduction angle of the triac from the initial value θa from time 0 to t1b. Decrease by “(1/60 × π / 2)”. Then, when “N = 60” is reached at time t1b, the addition operation is stopped, and the conduction angle of the triac is kept at a constant low value “π / 2” until the oven cooking is finished at time t2.

When the oven cooking is finished at the time t2, the control device 9 performs the subtraction operation of the counter from the time t2 to the time t2b and sequentially rewrites by subtracting the phase angle of the pulse signal. When "N = Na" is detected at time t2b, the counter subtraction operation is stopped and the phase angle is rewritten to a constant low value. Therefore, during the next oven cooking, the phase control is performed with the phase angle (conduction angle θa) when the subtraction operation is stopped as the initial value. The above-mentioned operations are performed based on the software configuration of the control device 9.

According to the above embodiment, the energization angle of the fan motor 7b is corrected by selecting the energization angle subtraction pattern according to the power supply voltage V of the fan motor 7b. Therefore, the fan motor 7b rotates at a constant speed without being affected by the magnitude of the power supply voltage V, so that the hot air supply amount into the cooking chamber 2 is more surely made uniform, and as a result, the finished state of the cooked product is obtained. Is further improved. In the third embodiment, the power supply voltage V is detected based on the software configuration of the control device 9, but the present invention is not limited to this, and a dedicated voltage sensor may be provided, for example.

Next, a fourth embodiment of the present invention will be described with reference to FIG. The same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Hereinafter, only different members will be described. When starting the oven cooking, the control device 9 reads the set temperature T by the temperature setting key 10c.

For example, the set value T of the internal temperature T is "T≤2.
In the case of "00 ° C", there is a circumstance that the on / off ratio of the heater 6 is small and the rise of the heater 6 is slow. Therefore, since the viscosity reduction rate of the grease contained in the sintered metal is low, the control device 9 sets the counter value N to "1" every 1 minute from time 0 to t1 as shown by the solid line α. 0.7 "each, and the conduction angle of the triac is gradually reduced according to the addition rate of N. At the same time, the count value N is compared with the set value N1, and at time t1, “N ≧ N1”
When the temperature is detected, the counting operation is stopped and the energization angle of the triac is kept at a constant low value θ1 until time t2 when the oven cooking ends.

Further, the set value T of the internal temperature T is "250 °
When C <T ≦ 300 ° C. ”, there is a circumstance that the on / off ratio of the heater 6 is large and the heater 6 rises quickly. Therefore, since the viscosity reduction rate of the grease contained in the sintered metal is high, the control device 9 controls
From time 0 to t1b, the value N of the counter is incremented by "2" every one minute, and the conduction angle of the triac is quickly reduced according to the addition rate of N. At the same time, the count value N is compared with the set value N3 (> N1), and when “N ≧ N3” is detected at time t1b, the addition operation is stopped and the energization angle of the triac is stopped until time t2 when the oven cooking is finished. It is kept at a constant low value θ3.

Further, when "200 ° C <T≤250 ° C", the on / off ratio of the heater 6 is medium, so that the control device 9 starts from time 0 to t1 as shown by the solid line β.
The value N of the counter is set to "1" every 1 minute until reaching a.
And the energization angle of the triac is adjusted according to the N addition rate. Then, the count value N is set to the set value N2 (N3
>N2> N1), and when “N ≧ N2” is detected, the addition operation is stopped and until the time t2 when the oven cooking ends,
The conduction angle of the triac is maintained at a constant low value θ2.

According to the above embodiment, the temperature setting key 10c
Select the addition rate of the counter according to the set temperature T by
The energization angle of the fan motor 7b was corrected. Therefore, the conduction angle of the trike can be adjusted according to the rate of decrease in viscosity of the grease based on the rising state of the heater 6, so that the rotation speed of the fan motor 7b is reliably kept constant. Therefore, the amount of hot air supplied to the cooking chamber 2 is surely made uniform, and as a result, the finished state of the cooked product is further improved.

Next, a fifth embodiment of the present invention will be described with reference to FIG. The same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Hereinafter, only different members will be described. The ROM of the control device 9 stores an arithmetic expression for setting the energization angle of the triac. This arithmetic expression is a function of the experimental data of FIG. 8 showing the relationship between the energization angle rad and the temperature T in the cooking chamber 2, and the control device 9 controls the temperature sensor 12 to start the oven cooking. Is read at a predetermined cycle to detect the temperature T in the cooking chamber 2. Then, the phase angle of the pulse signal is calculated by substituting the internal temperature T into the arithmetic expression, and the energization angle of the fan motor 7b is reduced as the internal temperature T rises.

According to the above embodiment, the amount of voltage applied to the fan motor 7b can be reduced according to the heating state of the grease contained in the sintered metal, that is, the decrease in the viscosity of the grease, so that the rotation speed of the fan motor 7b can be made constant. It Therefore, the amount of hot air supplied into the cooking chamber 2 is made uniform, and as a result, the finished state of the cooked product is also made uniform.

In the first to fifth embodiments, the experimental data is made into a function and stored in the ROM of the control device 9, but the present invention is not limited to this, and it is stored as a table, for example. It may be configured.

Further, in the above-mentioned first to fifth embodiments,
Although the triac is used as the switching element of the motor drive circuit 11, the present invention is not limited to this, and a thyristor such as GTO may be used.

[0047]

As is apparent from the above description, the heating cooker of the present invention has the following effects. According to the means described in claims 1 and 5, it is possible to reduce the amount of voltage applied to the fan motor according to the decrease in the viscosity of the grease contained in the sintered oil-impregnated bearing. For this reason, the rotation speed of the fan motor becomes constant, so that the hot air supply amount into the cooking chamber becomes constant,
As a result, the finished state of the cooked food is made uniform.

According to the second aspect, the conduction angle can be adjusted with the viscosity of the grease improved during non-cooking as the initial value. For this reason, the rotation speed of the fan motor is reliably made constant, so that the amount of hot air supplied to the cooking chamber is surely made constant, and as a result, the finished state of the cooked food is made more uniform.

According to the third aspect, the conduction angle of the fan motor can be corrected according to the power supply voltage of the fan motor. For this reason, the fan motor rotates at a constant speed without being affected by the magnitude of the power supply voltage, so that the amount of hot air supplied into the cooking chamber can be more reliably equalized, and as a result, the finished state of the cooked product can be further improved. To do.

According to the fourth aspect of the present invention, the conduction angle of the fan motor can be corrected according to the set value of the internal cold storage temperature (grease viscosity reduction rate). Therefore, since the fan motor rotates at a constant speed without being affected by the set value of the internal temperature,
The amount of hot air supplied to the cooking chamber is more surely made uniform, and as a result, the finished state of the cooked product is further improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention (a diagram showing how the conduction angle of a triac changes as the cooking time elapses).

FIG. 2 is a diagram showing the principle of phase control.

FIG. 3 is a vertical sectional view of a microwave oven.

FIG. 4 is a block diagram showing an outline of an electrical configuration.

FIG. 5 shows a second embodiment of the present invention, in which (a)
FIG. 4A is a diagram showing how the conduction angle of the triac changes with time, and FIG. 6B is a diagram showing how the counter value changes with time.

FIG. 6 shows a third embodiment of the present invention, (a)
Is a diagram corresponding to FIG. 5A when voltage correction is added, and FIG.
Is a diagram equivalent to (b) of FIG. 5 when voltage correction is added

FIG. 7 shows a fourth embodiment of the present invention, (a)
Is a diagram corresponding to (a) of FIG. 5 when temperature correction is added, (b)
Is a diagram equivalent to (b) of FIG. 5 when temperature correction is added

FIG. 8 is a diagram showing a fifth embodiment of the present invention (a diagram showing how the conduction angle of the triac changes as the temperature inside the refrigerator changes).

[Explanation of symbols]

2 is a cooking chamber, 6 is an annular heater (heat source), 7 is a fan device, 7a is a fan, 7b is a fan motor, 9 is a control device (motor control means, voltage detection means), and 12 is a temperature sensor (temperature detection means). Indicates.

Claims (5)

[Claims] 1. A fan device comprising a fan motor having a rotary shaft supported by a sintered oil-impregnated bearing, and a fan that rotates when the fan motor is driven, and the air discharged from the fan device is heated and heated. A heat source that generates hot air for cooking and a motor control unit that controls the phase of the fan motor of the fan device are provided, and the motor control unit reduces the conduction angle of the fan motor according to the elapse of heating and cooking time. Accordingly, the heating cooker is characterized in that the rotation speed of the fan motor is made substantially constant. 2. A time control means for performing an adding operation with the passage of time at the time of heating and a subtracting operation with the passage of time at the end of the cooking, wherein the motor control means has a time counting result of the time counting means. The cooking device according to claim 1, wherein the conduction angle of the fan motor is changed in response to the change. 3. A voltage detecting means for detecting the power supply voltage of the fan motor is provided, and the motor control means corrects the conduction angle of the fan motor according to the detection result of the voltage detecting means. Or the heating cooker according to 2. 4. A temperature setting means for setting the temperature inside the cooking chamber, wherein the motor control means corrects the conduction angle of the fan motor according to the value set by the temperature setting means. The heating cooker according to claim 1. 5. A fan device including a fan motor having a rotary shaft supported by a sintered oil-impregnated bearing and a fan that rotates when the fan motor is driven, and the air discharged from the fan device is heated and heated. A heat source that generates hot air for cooking, a motor control unit that controls the phase of the fan motor of the fan device, and a temperature detection unit that detects the temperature inside the cooking chamber, and the motor control unit is the temperature detection unit. A heating cooker characterized in that the rotation angle of the fan motor is made substantially constant by reducing the conduction angle of the fan motor as the temperature detected by the means increases.