JP2012189274A - Heating cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating cooker having a humidity sensor the detection accuracy of which is not degraded even with a small load.SOLUTION: The heating cooker has: a microwave generation means 1; a heating chamber 2 for receiving a load heated by microwave; a fan 3 for sending air into the heating chamber 2; the humidity sensor 4 for measuring the amount of steam in the heating chamber 2; an infrared sensor 5 for contactlessly detecting a temperature of the load; a load determination means 6 for determining the amount of the load in the heating chamber 2 from the temperature of the infrared sensor 5; and a control means 7 for controlling a rotational speed of the fan 3. The control means 7 controls the rotational speed of the fan 3 in conformity with the load determined by the load determination means 6, and changes an air amount to be sent into the heating chamber 2. By this arrangement, the detection accuracy of the humidity sensor 4 can be enhanced even with the small load, and thereby the heating can be stopped without being overheated even with any load.

Description

  The present invention relates to a cooking device used in general homes, restaurants, offices, and the like.

  Conventionally, this type of cooking device changes the number of rotations of the fan when using an infrared sensor and when using a humidity sensor, so that the steam in the heating chamber can be easily detected by each sensor. A method of discharging is disclosed (for example, see Patent Document 1).

JP 61-149732 A

  However, in the conventional configuration, since the amount of steam generated from food depends on the load amount, there is a problem that the detection accuracy of the humidity sensor is deteriorated when the load amount is small.

  Further, it is known that when a large amount of dry air is sent before steam is generated from the food, the food is dried and the finish is deteriorated (for example, JP-A-2006-46714).

  The present invention realizes the finish selected by the user without drying the food even if the load changes, and automatically stops heating without overheating even when a small load is heated An object of the present invention is to provide a cooking device that can be heated.

  The cooking device of the present invention includes a microwave generating means, a heating chamber that stores a load that is heated by microwaves, a fan that sends air into the heating chamber, a humidity sensor that measures the amount of steam in the heating chamber, An infrared sensor that detects the temperature of the load in a non-contact manner, a load amount determination unit that determines the amount of load in the heating chamber from the temperature of the infrared sensor, and a control unit that controls the rotational speed of the fan The control means controls the number of rotations of the fan in accordance with the load amount determined by the load amount determination means, and changes the amount of air sent into the heating chamber.

  As a result, even if the amount of steam generated due to the small amount of load is small, the detection accuracy of the humidity sensor can be kept from falling.

  The cooking device of the present invention can increase the detection accuracy of the humidity sensor even when the load amount is small, and can stop heating without being overheated at any load amount. In addition, it is possible to provide a cooking device having a good heating finish.

Sectional drawing of the heating cooker in Embodiment 1 of this invention The graph which shows the change of the humidity sensor of the cooking-by-heating machine in Embodiment 1 of this invention. The graph which shows the temperature change of the to-be-heated object of the heating cooker in Embodiment 1 of this invention. The graph which shows the temperature distribution of the heating cooker in Embodiment 1 of this invention The figure which shows the detection result of the humidity sensor of the heating cooker in Embodiment 1 of this invention. The graph which shows the rotation state of the fan of the heating cooker in Embodiment 3 of this invention, and the detected value of a humidity sensor.

  According to a first aspect of the present invention, there is provided a microwave generation means, a heating chamber that houses a load heated by microwaves, a fan that sends air into the heating chamber, a humidity sensor that measures the amount of steam in the heating chamber, and a non-contact type An infrared sensor for detecting the temperature of the load at the load, a load amount determination means for determining the amount of the load in the heating chamber from the temperature of the infrared sensor, and a control means for controlling the rotational speed of the fan, The control means controls the number of rotations of the fan in accordance with the load amount determined by the load amount determination means, and changes the amount of air sent into the heating chamber.

  As a result, even when the amount of steam generated due to a small amount of load is small, the detection accuracy of the humidity sensor can be kept from falling, and a cooking device with a good finish during automatic cooking and heating is provided. can do.

  The second invention has a movable part that can change the measurement range in the heating chamber by moving the infrared sensor, in particular, in the first invention, and the load amount determination means includes the temperature and measurement position of the infrared sensor. By determining the amount of load in the heating chamber from the information, the size of the load can be estimated from the range of temperature rise, and the determination accuracy of the load amount can be further increased.

  In particular, according to the third aspect of the present invention, the control means of the first aspect of the present invention increases the rotational speed of the fan when the load amount determined by the load amount determination means is smaller than when the load amount is large. When there is a small amount of air, the detection accuracy of the humidity sensor can be increased by allowing a large amount of air in the heating chamber to flow toward the humidity sensor.

  According to a fourth aspect of the present invention, in particular, when the load amount determined by the load amount determination means is determined to be small in the first invention, the output of the microwave generation means is decreased to reduce the load amount. It can prevent becoming easy to be heated.

  According to a fifth aspect of the present invention, in particular, in the first aspect of the invention, when the load amount determined by the load amount determination unit is small, the control unit intermittently repeats the rotation and stop of the fan, thereby rotating the fan. By stopping the operation, the steam is stored in the heating chamber, and then the fan is rotated to increase the amount of steam in the air flowing to the humidity sensor, thereby increasing the detection accuracy of the humidity sensor.

  In the sixth aspect of the invention, in particular, the load amount determination means of the first aspect of the invention corrects the determination of the load amount from the output of the humidity sensor before and after changing the rotational speed of the fan, and according to the result The control means estimates the load amount from the degree of influence of the fan rotation speed on the output of the humidity sensor by further changing the fan rotation speed, and adds the load amount determination result determined from the information of the infrared sensor. Thus, the load amount can be more accurately determined, and the detection accuracy of the humidity sensor can be improved by changing the rotation speed of the fan to be more optimal for the load amount.

  In the seventh aspect of the invention, in particular, the load amount determining means of the first aspect of the invention determines whether or not the load is stored frozen from the load temperature at the start of heating, and is stored frozen. If it is determined that there is a humidity sensor, the control means increases the fan speed more than if it is not determined that the product has been stored frozen, so that the humidity sensor It is possible to realize a heating cooker that can automatically heat the load temperature to an optimum state without lowering the detection accuracy.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1: shows sectional drawing of the heating cooker in the 1st Embodiment of this invention.

  In FIG. 1, a heating cooker according to the present embodiment includes a microwave generating unit 1, a heating chamber 2 that stores a load heated by microwaves, a fan 3 that sends air into the heating chamber 2, and a heating chamber 2. A humidity sensor 4 that measures the amount of vapor of the gas, an infrared sensor 5 that detects the temperature of the load in a non-contact manner, load amount determination means 6 that determines the amount of load in the heating chamber 2 from the temperature of the infrared sensor 5, It is comprised with the control means 7 which controls the rotation speed of the fan 3. FIG.

  The microwave generating means 1 usually uses a magnetron in many cases, but may be a semiconductor type.

  The microwave generation means 1 generates microwaves by supplying power from an inverter circuit (not shown) based on an instruction from the control means 7. The microwave to be generated is normally 2450 MHz, but is not limited thereto.

  Microwaves are introduced into the heating chamber 2 via a waveguide and an antenna (not shown), but the load is placed at the same position as the configuration in which a rotating base is provided so that the antenna is fixed and the load is rotated. In some cases, the antenna is configured to rotate.

  The heating chamber 2 is made of metal such as aluminum or SUS, and the load is heated by placing the load in the heating chamber 2 and introducing the microwave generated by the microwave generating means 1 into the heating chamber 2. The

  Although microwaves exist in the heating chamber 2, it is ideal that only the load is heated by the microwaves. Therefore, when the heating chamber 2 is made of, for example, glass, the glass generates heat due to microwaves, resulting in a heating loss. Therefore, in order to reduce the heating loss, it is desirable to use a metal that does not generate heat by the microwave and reflects the microwave. However, since it is necessary to introduce the microwave generated from the microwave generating means 1 into the heating chamber 2, only that portion is usually changed to another material.

  The fan 3 sends air outside the heating cooker into the heating chamber 2 via the intake port 8. The fan 3 is rotated, stopped, and controlled by the control means 7. Furthermore, the air sent into the heating chamber 2 by the fan 3 may be configured to be sent into the heating chamber 2 after cooling the microwave generating means 1 or an inverter circuit (not shown).

  The humidity sensor 4 detects steam (humidity) generated from the load. When the humidity sensor 4 is installed in the heating chamber 2, problems such as heat resistance and noise generation occur, and thus the humidity sensor 4 is installed in the exhaust port 9. The humidity sensor 4 includes a relative humidity sensor and an absolute humidity sensor, but either one may be used.

  The exhaust port 9 is for discharging steam or odor generated in the heating chamber 2 to the outside of the heating chamber 2, and the heating chamber 2 has a configuration in which steam or the like is difficult to leak from other than the exhaust port 9. . Further, the air is sent from the fan 3 into the heating chamber 2 so that the steam generated from the load can be detected quickly and reliably by the humidity sensor 4.

The infrared sensor 5 detects the temperature of the load in a non-contact manner, and there are a thermal type thermopile and a bolometer, or a quantum type photodiode and a phototransistor.
It can be anything.

  In particular, some thermopiles have a plurality of elements in one package, and each element can detect a temperature at a different position. Usually, in such an element, the temperature of each element is often taken out and used in many cases, but is not limited thereto.

  The movable part 10 is provided with an infrared sensor 5, and allows the infrared sensor 5 to measure different positions in the heating chamber 2 by moving the movable part 10.

  The use of a stepping motor is suitable for the movable unit 10 because the measurement position is determined, but a linear motor or the like may be used. Further, a rotary encoder or the like may be used for positioning.

  In addition, the movable part 10 may move the infrared sensor 5 one-dimensionally or may move two-dimensionally. The movable part 10 may be omitted, and in that case, the viewing angle of the infrared sensor 5 is often designed to be wide, but the present invention is not limited to this.

  The load amount determination means 6 determines the amount of load in the heating chamber 2, the result is transmitted to the control means 7, and the control means 7 changes the control method according to the load amount. The load amount determination means 6 and the control means 7 may be the same. Moreover, you may use the load amount which the load amount determination means 6 determined for the calculation which determines heating time.

  The fan 3 is connected to the control means 7, and the fan 3 is rotated and stopped, and the number of rotations is controlled. Further, the control means 7 may be connected to the microwave generation means 1, the humidity sensor 4, the infrared sensor 5, the load amount determination means 6, the movable part 10, and the like.

  When the user sets a heating method, time, or the like by an operation unit (not shown), the control means 7 operates an inverter circuit (not shown) to supply power to the microwave generation means 1, and the microwave generation means 1 Generate microwaves.

  The control means 7 moves the movable part 10, measures the temperature of the load placed in the heating chamber 2 by the infrared sensor 5, further controls the fan 3 and controls the amount of steam or humidity in the heating chamber 2 by the humidity sensor 4. Is measured, the operation state of the microwave generation means 1 is changed according to the results, and the operation of the microwave generation means 1 is stopped after the load is heated to a state desired by the user (for example, temperature). Take control.

  The control means 7 is often a microcomputer, a DSP, a custom IC, or the like, but is not limited thereto.

  About the cooking-by-heating machine comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  The user opens a door (not shown) and places a load in the heating chamber 2. In FIG. 1, the microwave generated by the microwave generating means 1 is introduced into the heating chamber 2 from a rotating antenna.

Since the antenna rotates, the distribution of the microwave in the heating chamber 2 changes every moment, and the microwave is heated no matter where the load is placed in the heating chamber 2. Therefore, in the cooking device having such a configuration, the user may place the load anywhere in the heating chamber 2, but when the antenna is fixed and the load is rotated, the rotation for rotating the load is performed. Since the platform exists, the user needs to place the load on the turntable, but either configuration may be used.

  The user determines a heating method by an operation unit (not shown). Usually, in the case of such a cooking device, there are many cases where several heating methods such as microwave heating, light heater heating, oven heating, superheated steam heating and the like can be selected. In this embodiment, the case of heating with microwaves will be described.

  In addition, there are a manual mode in which the user sets the output (heating power) and time and heats, and an automatic mode in which the heating is automatically stopped only by selecting cooking contents. When the user selects them and the door is closed, heating can be started.

  When heating is started, the control means 7 moves the infrared sensor 5 by the movable part 10, the infrared sensor 5 measures the temperature in the heating chamber 2, and the control means 7 receives the temperature information and changes the control content. To do.

  Further, the control means 7 controls the fan 3 to measure the steam amount or humidity in the heating chamber 2 by the humidity sensor 4, and changes the control content in response to the humidity information.

  For example, when a course for automatically warming is selected, heating is continued until the set temperature is reached, and when the set temperature is reached, the operation of the microwave generating means 1 is stopped and the heating is ended.

  At that time, it may be detected that the output of the infrared sensor 5 is equivalent to the set temperature, and the heating may be stopped, or the heating time may be calculated from the initial temperature and the load amount.

  Here, the humidity sensor 4 will be described with reference to FIG. FIG. 2 is a graph showing changes in the humidity sensor of the cooking device according to the first embodiment of the present invention. In FIG. 2, when the microwave generating means 1 is driven to heat the load, moisture contained in the load is heated and released as vapor.

  The amount of the released steam is extremely small (BA) at a low temperature, but the amount increases from a certain temperature (about 60 ° C.), eventually reaches boiling and releases a large amount of steam (C -A). The amount of steam generated at this time (BA or CA) depends on the amount of load.

  Therefore, assuming that the heating is stopped when the humidity sensor 4 detects the amount of B-A vapor, the finished temperature differs depending on the load amount. Therefore, in order to achieve the same finish temperature regardless of the load amount using the humidity sensor 4, it is necessary to cope with the difference in the load amount.

  Here, a method for determining the load amount will be described. FIG. 3 is a graph showing a temperature change of an object to be heated in the heating cooker according to the first embodiment of the present invention. As shown in FIG. 3, when different amounts of the same load are heated with microwaves of the same power, the time taken to heat from temperature A to temperature B is Ta in the case of a small amount, whereas In the case of a large amount, Tb is satisfied, and Ta <Tb.

  The relationship between Ta and Tb is almost proportional to the load amount. Therefore, when the temperature of the load after a predetermined time elapses is equal to or higher than the predetermined temperature, the load amount determination unit 6 detects that the load is a small amount.

Here, when the infrared sensor 5 is moved, the predetermined time cannot be set to be less than the time required for the movement, but needs to be a time that does not cause overheating even with a small load (for example, 15 seconds). ).

  Further, the predetermined temperature required for the determination is a temperature before overheating and is preferably equal to or lower than the heating target temperature. However, since the optimum temperature differs depending on the load, it is set to 50 ° C., for example.

  Alternatively, the load amount may be calculated from the time taken to reach a predetermined temperature (for example, 50 ° C.). Further, when the power of the microwave to be heated is different or not constant, the integrated power may be used instead of the time factor.

  FIG. 4 is a graph showing a distribution of temperatures detected by the infrared sensor 5 after a predetermined time has elapsed from the start of heating by the heating cooker according to the first embodiment of the present invention. Whereas there is a load, the temperature rises greatly (b to c), whereas in the positions where there is no load (ab, c, d), the temperature does not rise so much, so the magnitude of the load can be detected. . From these results, the load amount determination means 6 can determine the load amount.

  As another method for determining the load amount, there is another method in which a weight sensor is installed at a lower portion of the placement portion on which the load is placed, and the weight of the placement portion and the load is detected. However, since the weight data measured in this way includes the weight of the placing portion and the container on which the food that is the load is placed, it cannot be said that the weight is accurate.

  Therefore, in this embodiment, since the load amount is determined from the temperature rise of the load actually heated by the infrared sensor 5, the load amount can be accurately determined even if the initial temperature of the load changes.

  In the cooking device having such a configuration, the influence of the fan 3 will be described. In FIG. 1, the air inlet into the heating chamber 2 is one place of the intake port 8, and the air outlet is one place of the exhaust port 9.

  When the fan 3 is rotated by the control means 7, air is sent into the heating chamber 2, and air exits from the exhaust port 9.

  Here, if the fan 3 is stopped, air does not flow into the heating chamber 2 and at the same time, there is almost no air exiting from the exhaust port 9. Therefore, the steam generated by heating the load remains in the heating chamber 2 and the output of the humidity sensor 4 does not change.

  That is, in order to catch the change in humidity, the air in the heating chamber 2 needs to be discharged from the exhaust port 9, and for that purpose, the air needs to be sent into the heating chamber 2 by rotating the fan 3.

  FIG. 5 shows the detection result of the humidity sensor of the heating cooker according to the first embodiment of the present invention, and is the detection result of the humidity sensor 4 under a certain condition. The output of the humidity sensor 4 at the time of boiling is shown by changing the amount of water as a load, putting it in a mug, heating it with the same heating power. In addition, the speed of the fan at that time was measured with strong and medium.

  From FIG. 5, since the amount of generated steam is different when the load is changed even at the same boiling time, the output of the humidity sensor 4 becomes larger when the load is larger.

It can also be seen that the output of the humidity sensor 4 is larger when the rotation of the fan 3 is stronger.
Further, by reducing the rotation of the fan 3 from high to low, the output is reduced by about 30% when the load is large, and the output is reduced by about 70% when the load is small.

  That is, when the load amount is small, not only the output of the humidity sensor 4 is small, but also the dependence on the rotational speed of the fan 3 is high. For this reason, when the load is small, the output of the humidity sensor 4 is small, so that it is easily affected by noise and the like, and there is a problem in the detection accuracy of the humidity sensor 4.

  In the present embodiment, the control means 7 is a heating cooker that controls the rotation speed of the fan 3 in accordance with the load amount determined by the load amount determination means 6 and changes the amount of air sent into the heating chamber 2. It is.

  When it is determined by the load amount determination means 6 that the load is small, the output of the humidity sensor 4 is increased by increasing the number of revolutions of the fan 3 than when it is determined that the load is large. 4 detection accuracy can be increased.

  By doing so, it is possible to provide an easy-to-use cooking device that suppresses variations in the finished temperature when the food is warmed.

  Further, since the rotation speed of the fan 3 is increased only when the load is small, the food can be prevented from drying compared with the case where the rotation speed is constantly increased. Further, the noise of the fan 3 is reduced and the power consumption of the fan 3 is reduced. Reduction can also be achieved.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. Description of the same parts as those in the first embodiment will be omitted, and only differences will be described.

  As described in the first embodiment, the load amount determination unit 6 detects the temperature of the load amount by the infrared sensor 5 and determines the load amount. When the load is small, the temperature rises quickly, so even if the control means 7 stops the microwave generation means 1 according to the detection results of the infrared sensor 5 and the humidity sensor 4, the temperature is heated to a target temperature or higher. It is easy to end up.

  In order to prevent such a situation, in the present invention, when the load amount determined by the load amount determination unit 6 is determined to be small, the output of the microwave generation unit is reduced. By doing so, the rate of temperature rise of the load is alleviated and the accuracy of setting the load to the target temperature can be increased.

  Therefore, it is possible to provide a user-friendly cooking device that suppresses variations in the finished temperature when the food is warmed even when the load amount changes.

(Embodiment 3)
Next, a third embodiment of the present invention will be described. Description of the same parts as those in the first embodiment will be omitted, and only differences will be described.

  As described in the first embodiment, when the load amount is small, the amount of generated steam is small, and the humidity sensor 4 needs to capture the slight change, and is easily affected by noise or the like, resulting in a large error.

  As one of the countermeasures, as described in the first embodiment, a method of increasing the detection accuracy by increasing the number of rotations of the fan 3 to supply sufficient air to the humidity sensor 4 has been shown.

  As another countermeasure, in the present invention, when the load amount determined by the load amount determination unit 6 is small, the control unit 7 intermittently repeats rotation and stop of the fan 3.

  When the rotation of the fan 3 is stopped, the air in the heating chamber 2 remains in the heating chamber 2 because there is no pressure from the outside, and almost no air flows through the exhaust port 9. For this reason, the humidity sensor 4 cannot measure the humidity in the heating chamber 2.

  On the other hand, the load is heated by the microwave generating means 1 to generate steam, and the generated steam is accumulated in the heating chamber 2.

  After a certain period of time, steam has accumulated in the heating chamber 2, and when the fan 3 is rotated by the control means 7, the air in the heating chamber 2 is discharged from the exhaust port 9, and the humidity sensor 4 The humidity in 2 can be measured. The state at that time is shown in FIG.

  FIG. 6 is a graph showing the rotation state of the fan of the heating cooker and the detected value of the humidity sensor in the third embodiment of the present invention. 6A shows the detection value of the humidity sensor 4, and FIG. 6B shows the timing when the rotation of the fan 3 is on and off.

  Since the air around the humidity sensor 4 does not flow when the fan 3 is not rotating, the humidity sensor 4 continues to maintain the same detection value. However, when the fan 3 rotates, air is sent into the heating chamber 2 and heated. It can be seen that the humidity in the heating chamber 2 can be measured by the air in the chamber 2 being pushed out and flowing around the humidity sensor 4.

  Thus, even when the amount of steam generated due to a small load is small, the steam can be stored in the heating chamber 2 by temporarily stopping the fan, so that the generation from the load Even when the amount is small, measurement can be performed without reducing the detection accuracy of the humidity sensor.

  Here, the timing at which the fan 3 is rotated and stopped hardly generates steam at the initial stage of heating, and therefore the rotation of the fan 3 has little influence. However, when steam begins to be generated, the amount increases rapidly.

  Therefore, the fan may be stopped or fixed at the initial stage of heating, and the fan may be controlled in accordance with the increase in load temperature by the infrared sensor 5. The rotation time and the stop time of the fan 3 do not have to be the same time, and an off period, that is, a period for collecting steam may be determined in accordance with the detection accuracy of the humidity sensor 4.

  Further, the ON period of the fan 3 may be determined in consideration of the rise time of the rotation of the fan 3, or a certain time (for example, 5 second rotation, 5 second stop) may be simply repeated periodically. .

  The control means 7 varies or stops the output of the microwave generation means 1 based on the detection result of the humidity sensor 4 when the fan 3 is rotating. By performing such control, the detection accuracy of the humidity sensor 4 does not drop even when the load amount is small. Therefore, the cooking temperature is easy to use by suppressing variations in the finished temperature when the food is warmed. Can be provided.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described. Description of the same parts as those in the first embodiment will be omitted, and only differences will be described.

  As described in the first embodiment, the output of the humidity sensor 4 is greatly influenced by the amount of load and the speed of the fan 3. As described with reference to FIG. 5, by changing the speed of the fan 3 from strong to medium even under the same conditions, the load is reduced by about 30% when the load is large, whereas the load is reduced. If it is small, it decreases by about 70%.

  That is, the degree of influence due to the speed of the fan 3 varies depending on the load amount. Therefore, the load amount can be determined from the change rate of the output of the humidity sensor 4 before and after the change of the speed of the fan 3.

  Therefore, with respect to the load amount determined by the load amount determination means 6 from the output of the infrared sensor 5, the load amount is more accurately determined by the load amount determined from the influence of the change in the speed of the fan 3 on the output of the humidity sensor 4. However, by changing the speed of the fan 3 in accordance with the load, the humidity sensor 4 can be detected with higher accuracy, and the variation in the finished temperature when the food is warmed is suppressed and the heating is easy to use. A cooker can be provided.

(Embodiment 5)
Next, a fifth embodiment of the present invention will be described. Description of the same parts as those in the first embodiment will be omitted, and only differences will be described.

  Even if the load is the same, the amount of steam generated when it is heated differs depending on whether it is stored frozen or not. In general, since the amount of moisture is reduced in the case of being stored frozen, the amount of steam is reduced.

  That is, the output of the humidity sensor 4 becomes small and difficult to detect. Therefore, when the load stored in the frozen state is a load, the output of the humidity sensor 4 can be increased by increasing the number of revolutions of the fan 3 as described in the first embodiment, thereby preventing a decrease in detection accuracy. it can.

  Whether or not the load is stored frozen can be detected from the output of the infrared sensor 5. Therefore, when it is determined that the load is stored frozen, the control means 7 is stored frozen. It is possible to prevent the detection accuracy of the humidity sensor 4 from being lowered by increasing the number of rotations of the fan 3 compared to when it is not determined that the humidity sensor 4 has been determined.

  Therefore, it is possible to provide an easy-to-use heating cooker that suppresses variations in the finished temperature when a frozen and stored food is warmed.

  As described above, the heating cooker according to the present invention can increase the detection accuracy of the humidity sensor even when the load amount is small, and stops heating without being overheated at any load amount. Since the finish at the end of heating can be improved, it is useful for heating cookers used in general households.

DESCRIPTION OF SYMBOLS 1 Microwave generation means 2 Heating chamber 3 Fan 4 Humidity sensor 5 Infrared sensor 6 Load amount determination means 7 Control means 8 Intake port 9 Exhaust port 10 Movable part

Claims (7)

A microwave generating means, a heating chamber for storing a load heated by microwaves, a fan for sending air into the heating chamber, a humidity sensor for measuring the amount of steam in the heating chamber, and the temperature of the load in a non-contact manner An infrared sensor to detect; load amount determining means for determining the amount of load in the heating chamber from the temperature of the infrared sensor; and control means for controlling the number of rotations of the fan, wherein the control means includes the load amount A heating cooker that controls the number of rotations of the fan in accordance with the load amount determined by the determining means and changes the amount of air sent into the heating chamber. 2. A movable part capable of changing the measurement range in the heating chamber by moving the infrared sensor, and the load amount determination means determines the amount of load in the heating chamber from information on the temperature and measurement position of the infrared sensor. The heating cooker described in 1. The cooking device according to claim 1, wherein the control means increases the rotational speed of the fan when the load amount determined by the load amount determination means is smaller than when the load amount is large. The cooking device according to claim 1, wherein when the load amount determined by the load amount determination unit is determined to be small, the output of the microwave generation unit is reduced. The cooking device according to claim 1, wherein when the load amount determined by the load amount determination means is small, the control means intermittently repeats rotation and stoppage of the fan. The load amount determination means corrects the determination of the load amount from the output of the humidity sensor before and after changing the rotation speed of the fan, and the control means further changes the rotation speed of the fan according to the result. The heating cooker according to 1. The load amount determination means determines whether or not the load has been stored frozen from the load temperature at the start of heating. If it is determined that the load has been stored frozen, the control means is stored frozen. The heating cooker according to claim 1, wherein the number of rotations of the fan is set higher than that in a case where it is not determined that the fan has been caught.