JP2001304566A - High frequency heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high frequency heating device capable of heating concurrently different kinds some items to be heated to a proper temperature. SOLUTION: There are provided an electrical supplying port 19 arranged at a right side surface 11 forming a heating chamber 10, a magnetron 17, a mounting pan 20 on which an item to be heated is mounted, a rotary table 21, a driving motor 22, an infrared ray sensor 25 and a control means 24. The electrical supplying port 19 is oppositely faced against the circumferential edge of the rotary table 21 so as to form a non-uniform distribution of micro-wave for forcedly heating the item to be heated present in front of the electrical supplying port 19. The control means the item to be heated of low temperature in response to a signal of an infrared ray sensor 25, heats the item to be heated strongly to eliminate a lack of heating state for the item to be heated and at the same time the items to be heated of different types and different temperatures are heated concurrently to a proper temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency heating apparatus for dielectrically heating an object to be heated by using high-frequency energy, and more particularly to dielectrically heating the object to be heated while detecting the temperature of the object with an infrared sensor. Related to the device.

[0002]

2. Description of the Related Art Some conventional devices of this type are equipped with an infrared sensor. Further, there is a type provided with a two-stage mounting plate for dielectrically heating a plurality of foods at the same time.
In addition, the conventional high-frequency heating apparatus focuses on making the heating of the object to be heated housed in the heating chamber uniform, and as a means of making the heating uniform, a radio wave stirring method, a method of rotating the object to be heated, a plurality of methods, and the like. A power supply system and the like have been put to practical use.

[0003]

The conventional various heating methods are intended to eliminate the concentration of high frequencies in a specific area in the heating chamber since the main purpose is to make the heating of the object to be heated uniform. For this reason, when simultaneously heating a plurality of different objects to be heated, when one object to be heated is heated to an appropriate temperature, the other objects to be heated are insufficiently heated or overheated. It was difficult to simultaneously heat the object to be heated to an appropriate temperature.

An object of the present invention is to provide a high-frequency heating apparatus capable of simultaneously heating different types of objects to be heated to an appropriate temperature.

[0005]

In order to solve the above-mentioned problems, a high-frequency heating apparatus according to the present invention has a heating chamber for accommodating an object to be heated, a high-frequency generating means for generating a high frequency supplied to the heating chamber, A mounting plate on which the object to be heated is mounted, a rotating table on which the mounting plate is mounted, a power supply port provided facing a peripheral portion of the rotary table, and the high-frequency generating means generated in the power supply port. Waveguide for transmitting the high-frequency wave, rotation driving means for rotating the turntable, an infrared sensor having a viewing angle equivalent to a radius of the placing plate in front of the power supply port, and a detection signal of the infrared sensor. Control means for controlling the high-frequency generating means and the rotation driving means based on the high-frequency generating means and the rotation driving means, respectively, and the control means controls the lowest-temperature part in simultaneous heating of a part having a low temperature or a plurality of objects to be heated. Move the heated object in front of the power supply port It is intended to locked.

According to the above invention, since the peripheral portion of the mounting plate on the rotary table is located in front of the power supply port, the object to be heated placed on the mounting plate rotates with the rotation of the mounting plate. When it comes close to, it can be heated strongly. Since the infrared sensor makes almost the entire area of the mounting plate a detection field of view by one rotation of the mounting plate, the infrared sensor detects the temperature distribution of the entire area on the mounting plate and identifies the area where the object to be heated is present. Then, in the detection signal group of the infrared sensor corresponding to the existing area of the object to be heated, the area on the mounting plate corresponding to the low temperature signal is stopped in front of the power supply port to stop heating the low temperature area strongly. Then, the temperature difference from other areas is reduced. By using this heating method, objects to be heated having different types and temperatures can be simultaneously heated to a desired appropriate temperature.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A high-frequency heating apparatus according to a first aspect of the present invention includes a heating chamber for accommodating an object to be heated, a high-frequency generating means for generating a high frequency to be supplied to the heating chamber, and A mounting plate for placing, and a turntable for placing the placing plate described above,
A power supply port provided to face a peripheral portion of the turntable, a waveguide for transmitting a high frequency generated by the high frequency generation means to the power supply port, a rotation driving means for rotating the turntable, and the power supply port An infrared sensor having a viewing angle equivalent to the radius of the placing plate in front of the sensor, and control means for controlling the high-frequency generating means and the rotation driving means based on a detection signal of the infrared sensor, the control means Is to stop moving the lowest-temperature object to the front of the power supply port when heating the lower-temperature part of the object or a plurality of objects to be heated simultaneously. The high-frequency distribution on the placing plate forms a distribution in which the high-frequency electric field strength near the power supply port is strong due to the relative positional relationship between the power supply port and the turntable. Due to the non-uniform high-frequency distribution, the object to be heated placed on the mounting plate can be strongly heated when approaching the power supply port with the rotation of the mounting plate. Since the infrared sensor makes almost the entire area of the mounting plate a detection field of view by one rotation of the mounting plate, the infrared sensor detects the temperature distribution of the entire area on the mounting plate and identifies the area where the object to be heated is present. Then, in the detection signal group of the infrared sensor corresponding to the existence area of the object to be heated, the area on the mounting plate corresponding to the low temperature signal is stopped in front of the power supply port to stop heating the low temperature area strongly. Then, the temperature difference from other areas is reduced. By using this heating method, objects to be heated having different types and different temperatures can be simultaneously heated to a desired appropriate temperature.

According to a second aspect of the present invention, there is provided a high-frequency heating apparatus, wherein a gap between a peripheral portion of the turntable and the power supply port is set to a size that is approximately one-fourth of a high-frequency propagation wavelength in the waveguide. is there. The high frequency radiated from the power supply port into the heating chamber is coupled to the periphery of the turntable and propagates on the turntable. Thus, even when the object to be heated is placed substantially at the center of the placing plate, the side closer to the power supply port can be heated more strongly than the opposite side.

In the high frequency heating apparatus according to a third aspect of the present invention, after the control means rotates the object to be heated in front of the power supply port,
The object to be heated is reciprocated in front of the power supply port by bidirectional rotation control of a rotation driving unit. By reciprocating the object to be heated having a low temperature in front of the power supply port, overheating of a specific portion of the object to be heated can be suppressed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is an external configuration diagram of a high-frequency heating apparatus showing Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional configuration diagram of FIG.

In FIG. 1 and FIG. 2, a heating chamber 10 has a right wall surface 11, which is a metal boundary portion made of a metal material.
The left side wall 12, the back wall 13, the top wall 14, the bottom wall 15, and an opening / closing door 16 which is an opening / closing wall through which the object to be heated is put into and taken out of the heating chamber 10, are formed in a substantially rectangular parallelepiped shape, and the supplied high frequency wave is supplied to the inside thereof. It is formed to be substantially confined. Reference numeral 17 denotes a magnetron, which is a high-frequency generation unit that generates a high-frequency power to supply power to the heating chamber 10. Reference numeral 18 denotes a waveguide that guides the high-frequency generated by the magnetron 17 to the heating chamber 10.
9 couples the heating chamber 10 and the waveguide 18 in a high frequency manner and applies the high frequency generated by the magnetron 17 to the heating chamber 10.
It is a power supply port radiating inward, and is provided substantially at the center in the front-rear direction of the right wall surface 11 when viewed from the opening / closing door 16. Reference numeral 20 denotes a mounting plate on which an object to be heated is mounted, which is mounted on a turntable 21. The power supply port 19 is provided at a position facing the periphery of the turntable 21. Reference numeral 22 denotes a drive motor that is a rotation drive unit that rotates the mounting plate 20 together with the turntable 21, and rotates only in one direction. By operating the drive motor 22, the turntable 21 and the mounting plate 20 are rotated.

Reference numeral 23 denotes an inverter drive power supply for driving the magnetron 17, and reference numeral 24 denotes control means for controlling the operation of the entire apparatus. Reference numeral 25 denotes an infrared sensor having four detection elements. Each detection element is provided with a power supply port 19 on the right side wall 11.
Plate 20 through two holes 26 and 27 provided above
The amount of infrared light on the surface of the object to be heated or the amount of infrared light on the surface of the object to be heated is detected when the object to be heated is placed, and the detected signal is input to the control means 24. The detection area of the four detection elements of the infrared sensor 25 is indicated by a dot-dashed circle 2 in FIG.
It is set in the areas indicated by 8a to 28d. Detection area 28
“a” is set to a substantially central area of the placing plate 20, a detection area 28d is set to a peripheral area of the placing dish 20, and detection areas 28b and 28c are set to an area therebetween. Thus, the infrared sensor 25 can detect the temperature of almost the entire area of the placing plate 20 by rotating the placing plate 20 with the radius of the placing plate 20 as a detection area. The control means 24 is based on the heating information input from the operation unit and a signal from a weight sensor (not shown) for detecting the weight of the object to be heated via the infrared sensor 25 and the rotating shaft of the drive motor 22. Inverter drive power supply 2
By controlling the operation 3 and the operation of the drive motor 22, the object to be heated housed in the heating chamber 10 is dielectrically heated.

The mounting plate 20 is a round plate made of a ceramic material, and the turntable 21 is made of a metal material. Further, a heater (not shown) for radiation heating is provided outside the heating chamber 10 on the bottom wall surface 15 and the upper wall surface 14.

The operating unit includes a "thaw" key and a "warm" key for automatic heating control, a "heating time input unit" and a "heating temperature input unit" for executing heating based on the user's intention. It has a display section for displaying the temperature of the object to be heated during heating, a "start" key for inputting the start of heating, and a "cancel" key for clearing input conditions or interrupting heating.

Next, the means for simultaneously heating the different types of objects to be heated, which are the main objects of the present invention, to an appropriate temperature and the operation thereof will be described with reference to FIGS. 3 and 4. FIG.

FIG. 3 shows heating characteristics due to a non-uniform high-frequency distribution formed in the heating chamber. The objects to be heated were two mugs each containing 200 cc of water.
This is a characteristic under the condition that the mug is placed at two positions on the power supply port side and the opposite side symmetrically with respect to the center position of the placement plate 20 on a line connecting the rotation axis of the turntable 21 and the center axis of rotation. . The horizontal axis represents the mounting position of the object to be heated, and the vertical axis represents the ratio between the temperature rise value of the mug on the power supply port side and the temperature rise value of the mug placed on the opposite side of the power supply port. A in FIG. 3 indicates that each mug is placed in the center of the
C is placed on the peripheral edge of the mounting plate 20 separately,
B shows the case where they are respectively placed at the intermediate positions. The solid line 29 and the broken line 30 show the characteristics when the diameter of the turntable is 245 mm and 200 mm, respectively. These diameters are selected based on the gap between the periphery of the turntable 21 and the power supply port 19 (indicated by L in FIG. 2) based on the wavelength of the high-frequency wave propagating in the waveguide 18. That is, the waveguide 18
Has a width dimension of 90 mm and a propagation wavelength of about 166 mm
And the diameter of the turntable 21 forming a gap dimension of approximately 1/4 and approximately 3/8 of the propagation wavelength. When the diameter of the turntable 21 is 200 mm, the temperature rise rates of the water loads on the power supply port side and the opposite side are almost the same, but the diameter 245
With the turntable of mm, the water load on the power supply side could be heated strongly. When the diameter of the turntable 21 is 245 mm, the high frequency radiated from the power supply port 19 can be caused to propagate along the turntable 21, and when the mug is placed in the center of the mounting plate However, the object to be heated existing near the power supply port can be strongly heated. FIG. 4 is an external view of the turntable 21 according to the first embodiment.

Next, the operation procedure and control contents of the high-frequency heating apparatus having the above-described configuration will be described with reference to FIG. In the following description, control contents for automatically heating and cooking a plurality of objects to be heated will be described in order to clarify the features of the present invention. After storing and placing multiple objects to be heated in the heating chamber,
The user selects the “warm” key on the operation unit (S
101). Next, by pressing the "start" key (S102), dielectric heating of the object to be heated is started. Note that S103
Confirms that the "start" key has been pressed, and returns to S101 if the "cancel" key is pressed prior to the "start" key. In S104, the inverter drive power supply unit 23 is operated to operate the magnetron 17 and the power supply port 1
A high frequency is supplied into the heating chamber 10 through 9. Also S1
At step 05, the driving motor 22 of the turntable 21 is operated to rotate the mounting plate 20. The driving motor 22 is constituted by a synchronous motor, and when the commercial power frequency is 60 Hz, the
The time required to make one rotation of 0 is 10 seconds.

In S106, the control means 24 counts the elapsed time from the time when the driving power is supplied to the driving motor 22, and takes in the detection signal of the infrared sensor 25 at 0.5 second intervals. This detection signal is stored in a register 1 of 4 rows and 1 column indicating the current temperature, and the next signal (ie, after 0.5 seconds)
Hold the signal value until is input. On the other hand, the control means 24 has a register 2 composed of a matrix of 4 rows and 40 columns. The matrix register 2 includes a mounting plate 20
The above-mentioned temperature distribution data is stored. As soon as power is supplied to the drive motor 22, the detection signal of the infrared sensor 25 at that time is taken in and the register 1
To be stored. Then, after a lapse of 0.5 seconds, the data of the register 1 is stored in the register of the first column of the register 2 in the fourth row and the first column, and then the current detection signal of the infrared sensor 25 is stored in the register 1. Along with the operation elapsed time of the drive motor 22, the detection signal is stored in the register 2 as needed, and after 10 seconds elapse, the temperature distribution of the entire area on the mounting plate 20 is stored in the 1st to 20th rows of the register 2. The control means 24 stores the detection data taken in the next 10 seconds in the register 2
Store from column to column 40. Then, the detection data after 20.5 seconds is sequentially overwritten and stored from one column of the register 2.

The control means 24 operates from the first column of the register 2 to 2
The data in column 0 is compared with the data in columns 21 to 40, respectively, and it is determined that there is an object to be heated in a column exceeding a predetermined temperature rise, for example, 2 ° C. Based on the result, the positions of the plurality of objects to be heated on the mounting plate 20 are determined and S
Proceed to 107. Note that, even during this determination processing, since the placing plate 20 is continuously rotated,
Receives a new signal from the infrared sensor 25 as needed.

Next, in step S107, the temperature difference between the highest temperature and the lowest temperature of the group of rows (represented by the average temperature of each row) of the register 2 in which it is determined that there is an object to be heated is a predetermined temperature difference, for example, 10 ° C. Compare. When the temperature difference is less than 10 ° C., the process proceeds to S111, and the maximum temperature of each row group and the end heating temperature are compared. If the end heating temperature has not been reached, S10
Returning to 5, when the end heating temperature is reached, the process proceeds to S112. S
If the temperature difference becomes equal to or more than 10 ° C. in S 107, the process proceeds to S 108.

In step S108, the power supply to the drive motor 22 is cut off when the row corresponding to the lowest temperature in the row of the register 2 determined to have an object to be heated comes to the position facing the power supply port 19. . Then, the counting of the operation elapsed time of the drive motor 22 is stopped. In this state, the power supply port 19
The object to be heated existing at the position facing the object is dielectrically heated more strongly than the other object to be heated. Further, the infrared sensor 25 monitors only the surface temperature of the strongly heated object as needed. At this time, the data taken from the infrared sensor 25 is only the register 1.

Next, in S109, the temperature of the register 1 is compared with the end heating temperature. If the end heating temperature has been reached, the process proceeds to S112. If the end heating temperature has not been reached, S1
Go to 10.

In S110, it is determined whether or not the current temperature data obtained from the strongly heated object has risen from the previous minimum temperature to a temperature value equal to or higher than a predetermined value. The default value at this time is, for example, 15 ° C. which is 1.5 times the above temperature difference.

If the temperature has not reached the predetermined temperature, the flow returns to S108 to execute the contents of S108. If it is determined in S110 that the temperature of the register 1 has reached the predetermined temperature, the process proceeds to S11.
Proceed to 1. In S111, it is determined whether or not the maximum temperature of the average temperature in each row of the register 2 has reached a predetermined end heating temperature. If the end heating temperature has not been reached, the process returns to S105.

In S105, drive power is supplied to the drive motor 22 again. As a result, the mounting plate 20 starts to rotate again and the counting of the operation elapsed time of the drive motor 22 is started again. Also, the detection signal data of the infrared sensor 25 is sequentially taken into the register 1 and the data in the register 2 is updated. At this time, the update start column of the register 2 is S108
This is a column having the lowest temperature data at the time of execution. Therefore, at this time, the position of the object to be heated on the mounting plate 20 is in a known state. If the drive motor 22 operates continuously for 20 seconds or more, the data in the register 2 is all updated, so the position of the object to be heated may be determined again.

When it is determined in S109 that the maximum temperature of the register 1 has reached the end heating temperature, or in S111, it is determined that the average temperature of each row corresponding to the position of the object to be heated in the register 2 has reached the end heating temperature. When it is determined, the process proceeds to S112.

In S112, the operation of the inverter drive power supply 23 is stopped, and the flow proceeds to S113. In S113, the driving motor 2
The power supply of Step 2 is stopped to complete the dielectric heating of the object to be heated.

Next, the specific movement of the placing plate on which the object to be heated is placed will be described with reference to FIGS.

FIG. 6 shows a state in which frozen rice 31 (-18 ° C.) and refrigerated hamburger 32 (7 ° C.) are separately placed and heated. When the heating is started, the placing plate 20 is turned to an arrow 33.
Rotate in the direction indicated by. That is, when the object is placed in the state shown in FIG. 6A, the object to be heated moves in the heating chamber 10 as shown in FIG. During this time, the control means operates the detection area 2 of the infrared sensor 25 every 0.5 seconds.
The detection signals from 8a to 28d are taken in. In the state shown in FIG. 6A, the infrared sensor 25 detects the temperature of the frozen rice 31 and the temperature of the container and the dish of the refrigerated hamburger 32, respectively. On the other hand, in the state of FIG. 6B, the infrared sensor 25 detects the temperature of the plate of the refrigerated hamburger 32 and the temperature of the placing plate 20 in the detection region 28a, and the detection element of the detection region 28b mounts on the container of the frozen rice 31. The temperature of the tray 20 is detected, and the detection areas 28c and 28d detect the temperature of only the tray 20.

Then, the control means starts to determine the position of the object to be heated on the mounting plate from the time when the mounting plate 20 makes one rotation. When the placing plate 20 makes one more rotation, the control means confirms the existence of a plurality of objects to be heated and obtains temperature information of each object to be heated. When the temperature difference between the maximum temperature and the minimum temperature of each row of the register 2 which has been determined to include the object to be heated exceeds 10 ° C., the row of the register 2 having the lowest temperature faces the power supply port. When it comes, the power of the drive motor is cut off. Thereby, the placing plate 20 stops in a state where the low temperature food, for example, the frozen rice 31 is present at the position facing the power supply port 19, and the frozen rice 31 is strongly heated with respect to the refrigerated hamburger 32 so that the two foods are cooled. Reduce the temperature difference.

When the frozen rice 31 is heated to a desired temperature or higher in this state, the placing plate 20 rotates again. Then, the heated rice and the hamburger heated all over are heated almost equally by dielectric heating. When either the temperature of the rice or the hamburger reaches the end heating temperature of 75 ° C., the dielectric heating is completed. Thereby, the rice and the hamburger can be simultaneously heated to an appropriate temperature.

FIG. 7 shows a frozen hamburger 34 (−18).
C.) and a frozen potato 35 (-18 ° C.) are heated. In this case, the arrow 3 of the placing plate 20
The detection area 28 of the infrared sensor 25 with the rotation in six directions
a, 28b, and 28c pass over the respective heated objects. After the existence position of the heated object is determined in the same manner as in the above example, the row of the register 2 corresponding to the existing position of the frozen hamburger 34 is displayed. When the temperature becomes the lowest temperature below the predetermined temperature difference, the frozen hamburger 34 is located at the position facing the power supply port and corresponds to the detection areas 28a to 28b of the infrared sensor 25 as shown in FIG. At this position, the rotation of the mounting dish 20 is stopped, and the frozen hamburger 34 is strongly dielectrically heated with respect to the frozen potato 35. Subsequent operations are as described above. When either the temperature of the hamburger or the potato reaches the end heating temperature, the dielectric heating is completed, and both are heated to an appropriate temperature.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described. The second embodiment differs from the first embodiment in that the drive motor (corresponding to 22 in FIG. 1) of the turntable is bidirectionally controlled. The specific movement of the placing plate using the bidirectional rotation control will be described with reference to FIG. 8 and in comparison with FIG.

FIG. 8 shows a frozen rice 31 (−) as in FIG.
(18 ° C.) and refrigerated hamburger 32 (7 ° C.) are separately placed and heated. The drive motor controls rotation in one direction at the beginning of heating. When heating is started, the mounting plate 20 rotates in the direction indicated by the arrow 37. That is, when the table 20 is placed in the state shown in FIG.
The object to be heated moves in the heating chamber 10 as shown in FIG. During this time, the control means operates the infrared sensor 2 at 0.5 second intervals.
The detection signals from the five detection areas 28a to 28d are taken in. In the state of FIG. 8A, the infrared sensor 25 detects the temperature of the refrigerated hamburger 32 and the temperature of the dish, respectively. On the other hand, in the state of FIG.
And the temperature of the placing plate 20 are detected.

Then, the control means starts to determine the position of the object to be heated on the mounting plate from the time when the mounting plate 20 makes one rotation. When the placing plate 20 makes one more rotation, the control means confirms the existence of a plurality of objects to be heated and obtains temperature information of each object to be heated. When the temperature difference between the maximum temperature and the minimum temperature of each row of the register 2 which has been determined to include the object to be heated exceeds 10 ° C., the row of the register 2 having the lowest temperature faces the power supply port. When it comes, the power of the drive motor is cut off. Thereby, the placing plate 20 stops in a state where the low-temperature food, for example, the frozen rice 31 exists at the position facing the power supply port 19. Thereafter, the driving motor is controlled to rotate bidirectionally (arrow 38), and the placing plate 20 is reciprocated. This reciprocating rotation range is set to a rotation angle of approximately ± 45 degrees (39 in the figure) about a stop position in front of the power supply port. As a result, the entire frozen rice 31 is strongly heated with respect to the refrigerated hamburger 32 while avoiding overheating of the local portion of the frozen rice 31, thereby reducing the temperature difference between the two foods. Also in the case of this reciprocating rotation, the infrared sensor 25 takes in the temperature in a time cycle linked with the cycle of the reciprocating rotation. In this case, the temperature data fetched into the register 1 is transferred to the column designated by the register 2 at the timing when the next data is fetched, and the data in that column is updated.

When the frozen rice 31 is heated to a desired temperature or higher during the heating period in the reciprocating rotation state, the driving motor is again controlled to rotate in one direction, and the placing plate 20 is rotated in one direction. Then, the heated rice and the hamburger heated all over are heated almost equally by dielectric heating. When either the temperature of the rice or the hamburger reaches the end heating temperature of 75 ° C., the dielectric heating is completed. As a result, the rice and hamburger can be simultaneously heated to an appropriate temperature without local overheating.

As described above, in the present embodiment, the case where two different kinds of objects to be heated are heated at the same time has been described. It may be performed according to the case. That is, when heating three objects to be heated at the same time, first, the mounting plate is heated while rotating, and the object to be heated having the lowest temperature among the respective temperatures of the object to be heated at a certain point in time is selected. When the object to be heated arrives at a portion where radio waves are strong, the rotation of the mounting plate is stopped, and heating is performed in a state where radio waves are strong. By rotating the mounting plate and repeating the above process, all the objects to be heated can be heated to an appropriate temperature.

Further, the size of one heated object is large,
In the case where a temperature difference occurs in the object to be heated, assuming that one object to be heated is composed of two objects to be heated, that is, a high temperature object and a low temperature object, the present embodiment By using the same method as described above, the entirety of the single object to be heated can be adjusted to an appropriate temperature.

As described above, in the present embodiment, the strength of the high-frequency radio wave is formed between the power supply port and the turntable, and the difference in the strength of the radio wave is used. However, the object to be heated having a high temperature is weakly heated with weak radio waves, so that the entire object to be heated can be heated to an appropriate temperature.

In this embodiment, the case where four detecting elements are used for the infrared sensor has been described. However, the temperature measuring range of the normal element is a circle having a diameter of about 3 cm. Accuracy decreases and errors increase.
Further, if the range is narrowed, the accuracy is improved but the cost is high. Normally the radius of the food tray of the high frequency heating device is 15c
m, in this case 5 to measure the temperature of the entire radius.
Although four detection elements are required, four detection elements are used in this embodiment except for the center or the end of the mounting plate or between the detection ranges of the elements. As described above, the number of detection elements is not limited to the number in the present embodiment, and may be determined according to the size of the mounting plate and the required accuracy.

[0042]

As described above, the present invention has the following effects.

(1) Due to the relative positional relationship between the power supply port and the turntable, the high-frequency distribution on the mounting plate forms a distribution in which the high-frequency electric field strength near the power supply port is strong. Due to the non-uniform high-frequency distribution, the object to be heated placed on the mounting plate can be strongly heated when approaching the power supply port with the rotation of the mounting plate. Since the infrared sensor makes almost the entire area of the mounting plate a detection field of view by one rotation of the mounting plate, the infrared sensor detects the temperature distribution of the entire area on the mounting plate and identifies the area where the object to be heated is present. Then, in the detection signal group of the infrared sensor corresponding to the existing area of the object to be heated, the area on the mounting plate corresponding to the low temperature signal is stopped in front of the power supply port to stop heating the low temperature area strongly. Then, the temperature difference from other areas is reduced. By using this heating method, objects to be heated having different types and temperatures can be simultaneously heated to a desired appropriate temperature.

(2) By optimizing the gap size between the periphery of the turntable and the power supply port, the high frequency radiated from the power supply port into the heating chamber is coupled to the periphery of the turntable and propagates on the turntable. . Thus, even when the object to be heated is placed substantially at the center of the placing plate, the side closer to the power supply port can be heated more strongly than the opposite side.

(3) After the object to be heated is rotated in front of the power supply port, the object to be heated is reciprocated in front of the power supply port to suppress overheating of a specific portion of the object to be heated. it can.

[Brief description of the drawings]

FIG. 1 is an external configuration diagram of a high-frequency heating device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the high-frequency heating device.

FIG. 3 is a heating characteristic diagram using the turntable of the high-frequency heating device.

FIG. 4 is an external configuration diagram of a turntable of the high-frequency heating device.

FIG. 5 is a flowchart showing control contents of the high-frequency heating device.

FIG. 6 (a) is a diagram showing a state of heating control of a specific example 1 of the high-frequency heating device. (B) is a diagram showing a state of heating control of a specific example 1 of the high-frequency heating device.

7A is a diagram showing a state of heating control in a specific example 2 of the high-frequency heating device. FIG. 7B is a diagram showing a state of heating control in a specific example 2 of the high-frequency heating device.

FIG. 8A is a diagram illustrating a state of heating control of a specific example of the high-frequency heating device according to the second embodiment of the present invention. FIG. 8B is a diagram illustrating a state of heating control of a specific example of the high-frequency heating device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Heating chamber 17 Magnetron (high frequency generation means) 18 Waveguide 19 Power supply port 20 Placement dish 21 Turntable 22 Drive motor (rotation drive means) 24 Control means 25 Infrared sensor

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Akemi Fukumoto 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 3K086 AA01 BA08 BB02 BB08 CA04 CB04 CB12 CB15 CC01 CC06 CD09 CD19 CD27 DA02 DB11 3K090 AA01 AB02 AB03 BA01 BB01 CA02 DA19 EA01 EB14 EB16 3L086 AA04 BB05 BF07 CB08 CB16 CC03 CC08 CC14 DA03 DA12 DA29

Claims (3)

[Claims] 1. A heating chamber for accommodating an object to be heated, high frequency generating means for generating a high frequency to be supplied to the heating chamber, a mounting plate for mounting the object to be heated, and a mounting plate for mounting the object to be heated. Turntable, and a power supply port provided facing the periphery of the turntable,
A waveguide for transmitting the high frequency generated by the high frequency generating means to the power supply port, a rotation driving means for rotating the turntable, and an infrared ray having a viewing angle corresponding to a radius of the placing plate in front of the power supply port. A sensor, and control means for controlling the high-frequency generation means and the rotation driving means based on a detection signal of the infrared sensor, wherein the control means controls a low-temperature portion of the object to be heated or a plurality of objects to be heated. In the simultaneous heating, a high-frequency heating device that stops moving an object to be heated having the lowest temperature in front of the power supply port. 2. The high-frequency heating apparatus according to claim 1, wherein the gap between the peripheral portion of the turntable and the power supply port is approximately 略 of the high-frequency propagation wavelength in the waveguide. 3. The control means rotates the object to be heated in front of the power supply port, and then bi-directionally controls the rotation driving means to reciprocate the object to be heated in front of the power supply port.
The high-frequency heating device as described.