JP6073196B2 - High frequency heating device - Google Patents

Description

  The present invention relates to a high-frequency heating device, and more particularly to a high-frequency heating device that heats an object to be heated using a microwave.

  Conventionally, as a high-frequency heating device, the anode current of a magnetron detected by an anode current detection resistor is analog-digital converted by an A / D converter to obtain an anode voltage, and a microcomputer detects an abnormality of the magnetron based on the anode voltage. Some have an abnormality detection circuit for detecting an operation (see, for example, Japanese Patent Application Laid-Open No. 2008-292089 (Patent Document 1)).

JP 2008-292089 A

  By the way, in the above high-frequency heating device, when the abnormality detection circuit fails, for example, when the anode current detection resistor is opened, the microcomputer that controls the inverter circuit by the high voltage generated by the magnetron fails, and the magnetron May operate in an unstable state, and there is a problem that the inverter circuit cannot be safely stopped during such abnormal operation of the magnetron.

  Accordingly, an object of the present invention is to provide a high-frequency heating device that can reliably stop an inverter circuit during abnormal operation of a magnetron even if an abnormality detection circuit fails.

In order to solve the above problems, the high-frequency heating device of the present invention is:
A magnetron that generates a high frequency for heating the object to be heated;
An inverter circuit for driving the magnetron;
An inverter drive circuit for outputting a drive signal to the inverter circuit;
An abnormality detection circuit for detecting abnormal operation of the magnetron;
The inverter circuit and the inverter circuit board on which the abnormality detection circuit is mounted,
A conductive pattern for the drive signal from the inverter drive circuit and a conductive pattern for an abnormality detection signal output from the abnormality detection circuit are formed on the inverter circuit board,
The conductive pattern for the abnormality detection signal and the conductive pattern for the drive signal have regions close to each other,
Due to the abnormal operation of the magnetron, a high voltage is generated in the conductive pattern for the abnormality detection signal, and a discharge is generated from the conductive pattern for the abnormality detection signal to the conductive pattern for the drive signal in the region adjacent to each other. The drive signal from the inverter drive circuit is turned off.

Moreover, in the high-frequency heating device of one embodiment,
The inverter drive circuit includes a transistor that outputs the drive signal,
In the region where the conductive pattern for the abnormality detection signal and the conductive pattern for the drive signal are close to each other, the abnormal operation of the magnetron causes a discharge from the conductive pattern for the abnormality detection signal to the conductive pattern for the drive signal. When this occurs, the transistor of the inverter drive circuit becomes inoperative.

Moreover, in the high-frequency heating device of one embodiment,
In the region where the conductive pattern for the abnormality detection signal and the conductive pattern for the drive signal are close to each other, the abnormal operation of the magnetron causes a discharge from the conductive pattern for the abnormality detection signal to the conductive pattern for the drive signal. When this occurs, the conductive pattern for the drive signal is disconnected by discharge.

Moreover, in the high-frequency heating device of one embodiment,
The abnormality detection circuit has an anode current detection resistor or a current transformer for detecting the anode current of the magnetron.

  As is apparent from the above, according to the present invention, a high voltage is generated in the abnormality detection signal conductive pattern due to the abnormal operation of the magnetron, and the drive signal conduction from the abnormality detection signal conductive pattern in a region close to each other. A high-frequency heating device that can reliably stop the inverter circuit during abnormal operation of the magnetron even if the abnormality detection circuit fails, because the drive signal from the inverter drive circuit is turned off due to discharge occurring in the pattern. Can be realized.

FIG. 1 is a front view of a microwave oven as an example of the high-frequency heating device according to the first embodiment of the present invention. FIG. 2 is a block diagram of the main part of the microwave oven. FIG. 3 is a block diagram of the main part when the abnormality detection circuit of the microwave oven fails. FIG. 4 is a schematic diagram of a conductive pattern for driving signals and a conductive pattern for abnormality detection signals of the microwave oven. FIG. 5 is a schematic diagram of a microwave oven drive signal conductive pattern and an abnormality detection signal conductive pattern as an example of the high-frequency heating device according to the second embodiment of the present invention. FIG. 6 is a block diagram of the main part of the microwave oven of the comparative example. FIG. 7 is a block diagram of the main part when the abnormality detection circuit of the microwave oven of the comparative example fails. FIG. 8 is a back view of the microwave oven as an example of the high-frequency heating device according to the third embodiment of the present invention as viewed from obliquely above. FIG. 9 is a cross-sectional view of a main part of a door glass of a microwave oven as an example of the high-frequency heating device according to the fourth embodiment of the present invention. FIG. 10 is a cross-sectional view of a main part of a door glass of another example of the microwave oven. FIG. 11 is a cross-sectional view of a main part of a door glass of a conventional microwave oven. FIG. 12 is a control block diagram of a microwave oven as an example of the high-frequency heating device according to the fifth embodiment of the present invention. 13 (a) and 13 (b) are cross-sectional views of a net on which a microwave oven fish as an example of the high-frequency heating device according to the seventh embodiment of the present invention is placed. 14 (a) and 14 (b) are cross-sectional views of a net on which a microwave oven fish as an example of the high-frequency heating device according to the eighth embodiment of the present invention is placed. 15 (a) and 15 (b) are cross-sectional views of a net on which a microwave oven fish as an example of a high-frequency heating device according to the ninth embodiment of the present invention is placed.

  Hereinafter, the high-frequency heating apparatus of the present invention will be described in detail with reference to the illustrated embodiments.

[First Embodiment]
FIG. 1 shows a front view of a microwave oven as an example of the high-frequency heating device according to the first embodiment of the present invention.

  As shown in FIG. 1, the microwave oven according to the first embodiment has a heating chamber 8 in a rectangular parallelepiped casing 1, and the front opening of the heating chamber 8 rotates about a lower end side. A door 2 is attached. A handle 3 is attached to the door 2 and a heat-resistant door glass 4 is attached to the door 2. An operation panel 5 is provided on the right side of the door 2. The operation panel 5 includes a display unit 6 and a button group 7.

  FIG. 2 shows a block diagram of the main part of the microwave oven. As shown in FIG. 2, the microwave oven includes a control board 10 as an example of an inverter drive circuit, an inverter circuit board 20 controlled by the control board 10, and a magnetron 30 driven by the inverter circuit board 20. ing.

  The control board 10 includes a control circuit 11, a transistor 12 that outputs a drive signal from the control circuit 11, and a connector CN1. The drive signal output from the control circuit 11 is a repetitive signal, a serial signal, a PWM (pulse width modulation) signal, or the like.

  The inverter circuit board 20 includes a connector CN2 connected to the connector CN1, a control circuit 21 that receives a drive signal input via the connector CN2, and a drive circuit 22 that is controlled by the control circuit 21 and drives the magnetron 30. And an iterative detection circuit 23 and an abnormality detection circuit 24. The control circuit 21, the drive circuit 22, and the repeated detection circuit 23 constitute an inverter circuit.

  In the connectors CN1 and CN2, the ground GND is connected to the terminal (1), the abnormality detection signal (detection signal in FIG. 2) is connected to the terminal (2), and the drive signal is connected to the terminal (3).

  The abnormality detection circuit 24 includes an anode current detection resistor (not shown) that detects the anode current of the magnetron 30. A ground GND is connected to one end of the anode current detection resistor (not shown), and a conductive pattern 27 for an abnormality detection signal is connected to the other end. A current transformer may be used instead of the anode current detection resistor.

  The drive signal from the control circuit 11 of the control board 10 is amplified by the transistor 12, and the drive circuit 22 of the inverter circuit board 20 and the repetitive detection circuit via the terminal (3) of the connector CN1 and the terminal (3) of the connector CN2. 23. The magnetron 30 is driven by the drive circuit 22 to which this drive signal is input.

  When the magnetron 30 operates abnormally and the anode current increases, the voltage across the anode current detection resistor increases. The abnormality detection circuit 24 outputs an abnormality detection signal (detection signal in FIG. 2) proportional to the anode current, and the abnormality detection signal is controlled via the terminal (3) of the connector CN2 and the terminal (3) of the connector CN1. Input to the control circuit 11 of the substrate 10. When the voltage level of the abnormality detection signal exceeds a predetermined level, the control circuit 11 of the control board 10 stops the inverter circuit (21, 22, 23) by turning off the output of the drive signal.

  The inverter circuit board 20 is formed with a conductive pattern 26 for driving signals from the control board 10 and a conductive pattern 27 for abnormality detection signals output from the abnormality detection circuit 24 on the inverter circuit board 20. . The drive signal conductive pattern 26 and the abnormality detection signal conductive pattern 27 are close to each other in the region S. In this embodiment, copper wire patterns are used for the conductive pattern 26 for drive signals and the conductive pattern 27 for abnormality detection signals.

  In the region S where the drive signal conductive pattern 26 and the abnormality detection signal conductive pattern 27 are close to each other, as shown in FIG. 4, the drive signal conductive pattern 26 and the abnormality detection signal conductive pattern 27 Discharge portions 26a and 27a each having a sharp tip extending from one to the other are formed.

  In the microwave oven having such a configuration, when the abnormality detection circuit 24 fails at the location A shown in FIG. 3, more specifically, when the connection between the abnormality detection circuit 24 and the ground GND is opened, the abnormal operation of the magnetron 30 is performed. Thus, the high voltage generated in the conductive pattern 27 for the abnormality detection signal can be applied to the conductive pattern 26 for the drive signal by discharging through the discharge portions 26a and 27a.

  As a result, the high voltage applied to the drive signal conductive pattern 26 causes the transistor 12 of the control substrate 10 (inverter drive circuit) connected to the drive signal conductive pattern 26 to be destroyed by the high voltage to be in an inoperative state. As a result, the drive signal is turned off, and the inverter circuits (21, 22, 23) are stopped. Thus, even if the abnormality detection circuit 24 fails, the inverter circuits (21, 22, 23) can be reliably stopped when the magnetron 30 operates abnormally.

  FIG. 6 shows a block diagram of the main part of the microwave oven of the comparative example. The block diagram shown in FIG. 2 of the first embodiment is different from the conductive pattern 126 for the drive signal and the conductive pattern 127 for the abnormality detection signal. Are different in that they are not close together. This comparative example is not the high-frequency heating device of the present invention.

  When the abnormality detection circuit 24 of the microwave oven in the comparative example fails at the location B shown in FIG. 7, a high voltage is generated in the conductive pattern 127 for the abnormality detection signal due to the abnormal operation of the magnetron 30, and The control circuit 11 of the control board 10 connected to the conductive pattern 127 is destroyed. For this reason, although the operation of the control circuit 11 becomes unstable, the control circuit 11 continues to output the drive signal, and the inverter circuits (21, 22, 23) do not stop the operation.

  On the other hand, in the microwave oven according to the first embodiment, even if the abnormality detection circuit 24 fails, the inverter circuit (21, 22, 23) can be stopped reliably when the magnetron 30 operates abnormally. It can be stopped safely.

  According to the microwave oven of the first embodiment, as shown in FIG. 3, in the region S where the drive signal conductive pattern 26 and the abnormality detection signal conductive pattern 27 on the inverter circuit board 20 are close to each other, The high voltage generated in the abnormality detection signal conductive pattern 27 due to the abnormal operation of the magnetron 30 in a state where the abnormality detection circuit 24 has failed can be applied to the drive signal conductive pattern 26 by discharge through the discharge portions 26a and 26b. To.

  As a result, the high voltage generated in the abnormality detection signal conductive pattern 27 due to the abnormal operation of the magnetron 30 is applied to the drive signal conductive pattern 26, and the transistor 12 that outputs the drive signal of the inverter drive circuit 10 has a high voltage. It is destroyed and becomes inoperable. Therefore, even if the abnormality detection circuit 24 fails, the inverter circuits (21, 22, 23) can be stopped more reliably when the magnetron 30 operates abnormally.

  If the magnetron 30 operates abnormally when the anode current detection resistor (or current transformer) for detecting the anode current of the magnetron 30 is opened and the abnormality detection circuit 24 fails, the magnetron 30 is connected to the anode current detection resistor. A high voltage is generated from the magnetron 30 in the conductive pattern 27 for the abnormality detection signal. The high voltage generated in the abnormality detection signal conductive pattern 27 is applied to the drive signal conductive pattern 26 to destroy the transistor 12 of the inverter drive circuit 10 or to disconnect the drive signal conductive pattern 26. As a result, the inverter circuits (21, 22, 23) can be stopped reliably.

[Second Embodiment]
FIG. 5 is a schematic diagram of a microwave pattern drive signal conductive pattern and a detection signal conductive pattern as an example of the high-frequency heating device according to the second embodiment of the present invention. The microwave oven according to the second embodiment has the same configuration as the microwave oven according to the first embodiment except for the discharge portion of the conductive pattern for the drive signal and the conductive pattern for the abnormality detection signal. 2 is used.

  As shown in FIG. 5, discharge portions 26b and 27b each having a sharp tip extending from one of the drive signal conductive pattern 26 and the abnormality detection signal conductive pattern 27 toward the other are formed. The discharge portion 26b is formed by bending the drive signal conductive pattern 26 in a dogleg shape toward the abnormality detection signal conductive pattern 27 side. Further, the discharge portion 27b is formed by bending the abnormality detection signal conductive pattern 27 in a dogleg shape toward the drive signal conductive pattern 26 side.

  The discharge portions 26b and 27b of the drive signal conductive pattern 26 and the abnormality detection signal conductive pattern 27 are generated in the abnormality detection signal conductive pattern 27 by the abnormal operation of the magnetron 30 in a state where the abnormality detection circuit 24 has failed. The applied high voltage is applied to the drive signal conductive pattern 26 via the discharge portions 26b and 27b, and the drive signal conductive pattern 26 is disconnected by discharge. That is, the shortest distance between the discharge portions 26b and 27b is set to a distance that can be discharged with a high voltage generated during the abnormal operation of the magnetron 30, and the line width of the conductive pattern 26 for the drive signal is set to the abnormal operation of the magnetron 30. It is set to a value at which disconnection occurs due to the discharge current assumed to flow sometimes.

  Thereby, even if the abnormality detection circuit 24 breaks down, the inverter circuit (21, 22, 23) can be stopped more reliably by disconnecting the conductive pattern 26 for the drive signal.

  The microwave oven of the second embodiment has the same effect as the microwave oven of the first embodiment.

[Third Embodiment]
FIG. 8: has shown the back view seen from diagonally upward of the microwave oven as an example of the high frequency heating apparatus of 3rd Embodiment of this invention. The microwave oven of the third embodiment has the same configuration as the microwave oven of the first embodiment except for the deep drawing portion of the rear plate, and FIG.

  As shown in FIG. 8, the microwave oven according to the third embodiment includes a rear plate 40 that is bent into an L-shaped cross section that covers the rear and bottom surfaces of the heating chamber 8. The rear plate 40 has a rear surface portion 40 a that covers the rear surface of the heating chamber 8 and a bottom surface portion 40 b that covers the bottom surface. And the deep drawing part 41 which protrudes back is provided in the rear surface part 40a of the rear board 40. As shown in FIG. An exhaust port 42 composed of a plurality of slits is provided on one of the side surfaces of the deep drawing portion 41.

  Further, an exhaust cover 43 is attached to cover the exhaust port 42 of the deep drawing portion 41 from the side. The upper part of the exhaust cover 43 is open, and the bottom is closed.

  Further, an exhaust port 8 a composed of a plurality of holes is provided on the back side of the heating chamber 8. Exhaust gas containing water vapor discharged from the inside of the heating chamber 8 through the exhaust port 8 a is exhausted from the side exhaust port 42 through the deep drawing portion 41 of the rear plate 40 and then guided upward by the exhaust cover 43. Discharged.

  Further, in the rear surface portion 40a of the rear plate 40, a cut and raised portion 43 that opens obliquely upward toward the outside is provided in a region near the exhaust port 42 covered with the exhaust cover 43. By this cut and raised 43, water droplets generated by condensation of water vapor on the rear surface portion 40a are returned into the main body and received by a drain pan (not shown) provided at the bottom of the main body, and then a dew receiving portion (not shown). I am trying to receive it at.

  According to the microwave oven having the above-described configuration, the exhaust gas exhausted from the heating chamber 8 to the rear surface side is exhausted from the exhaust port 42 on the side surface of the deep drawing portion 41 so that the rear surface can be installed close to the wall. Therefore, installation space and product depth can be shortened.

  In addition, even if it discharges to the side from the exhaust port 42 of the deep throttle part 41 without the exhaust cover 43, it becomes possible to install the rear surface close to the wall.

[Fourth Embodiment]
FIG. 9: has shown sectional drawing of the principal part of the door glass of the microwave oven as an example of the high frequency heating apparatus of 4th Embodiment of this invention. The microwave oven of the fourth embodiment has the same configuration as the microwave oven of the first embodiment except for the door glass adhesive structure, and FIG.

  In the microwave oven according to the fourth embodiment, when the door glass 4 is attached to the door 2, the viscous adhesive 55 is poured into the groove 50 provided in the frame portion of the door 2, and the door glass 4 is attached to the door 2. . The groove 50 of the door 2 includes a groove body 51 having a rectangular cross section and a gap portion 52 extending to the side of the groove body 51.

  Here, the adhesive 55 is put into the groove 50 so as to protrude from the groove main body 51 and partially reach the side gap portion 52.

  In a conventional microwave oven door glass, as shown in FIG. 11, in order to fill the groove 70 with no gap, it is necessary to strictly control the amount of the adhesive 75, which cannot be done manually.

  On the other hand, in the fourth embodiment, even if a large amount of the adhesive 55 is put in the groove main body 51, the portion protruding from the groove main body 51 escapes to the gap portion 52. Therefore, the amount of the adhesive 55 is strictly controlled. Without management, the door glass 4 can be bonded to the door 2 so that the adhesive 55 does not protrude from the groove.

  Moreover, FIG. 10 has shown sectional drawing of the principal part of the door glass of the other example of the said microwave oven. In FIG. 10, the groove 60 of the door 2 includes a groove main body 61 having a rectangular cross section, a gap portion 62 extending to the side of the groove main body 61, and a rib standing between the groove main body 61 and the gap portion 62. 63.

  Also in FIG. 10, even if a large amount of adhesive 65 is put in the groove main body 61, the portion protruding from the groove main body 61 escapes to the gap 62 through the rib 63, so the amount of the adhesive 65 is strictly controlled. The door glass 4 can be bonded to the door 2 without the adhesive 65 protruding from the groove.

  9 and 10, the gap portions 52 and 62 are provided on one side of the groove main bodies 51 and 61, but may be provided on both sides of the groove main body.

  In addition, although the said 4th Embodiment demonstrated adhesion | attachment of the door glass 4 to the door 2 of a microwave oven, not only this but the substance which has viscosity, such as an adhesive agent, in the groove | channel provided in the 1st board | plate material. You may apply to the structure which burys and attaches a 2nd board | plate material to a 1st board | plate material.

  In addition, a hole or a slit or the like through which a viscous substance such as an adhesive leaks is provided at the bottom of the groove provided in the first plate material, so that the material having a large viscosity in the groove is applied to the first plate material. A structure may be adopted in which a substance having viscosity escapes not in the lateral direction of the groove but in the longitudinal direction by leaking from a hole or a slit when the second plate member is attached.

[Fifth Embodiment]
FIG. 12 shows a control block diagram of a microwave oven as an example of the high-frequency heating device according to the fifth embodiment of the present invention. The microwave oven of the fifth embodiment has the same configuration as the microwave oven of the first embodiment except for the function of heating using an infrared sensor and water vapor, and FIGS. 1 and 2 are used.

  The microwave oven according to the fifth embodiment includes a control device 100 that controls the magnetron 30 and the heater 110 as shown in FIG. In this control device 100, a multi-eye infrared sensor 9 that detects the temperature in the heating chamber 8 and an operation panel 5 are connected.

  The control device 100 includes a microcomputer, an input / output circuit, and the like. Based on a detection signal from the heating control unit 100a that controls the magnetron 30 and the heater 110 and the infrared sensor 9, the presence or absence of water for generating steam is determined. A determination unit 100b for determination.

  A steam generating container (not shown) filled with water is placed at the bottom of the heating chamber 8 shown in FIG. 1, and the water in the steam generating container is heated by heating with a microwave output from the magnetron 30. To generate water vapor. Heating is performed with microwaves while water is given to the surface of the object to be heated with water vapor generated in the heating chamber 8. In addition, before cooking, the inside of the heating chamber 8 without an object to be heated is preliminarily filled with steam with steam generated from the steam generating container.

  This microwave oven detects the temperature of the water in the steam generating container heated by the microwave by the multi-eye type infrared sensor 9. The steam generating container is placed at a predetermined position (for example, the back corner) at the bottom of the heating chamber 8. The multi-eye type infrared sensor 9 can detect the temperature of each region obtained by dividing the bottom of the heating chamber 8 into a plurality of portions, and one of the regions is a position where the team generating container is placed.

  The determination unit 100b of the control device 100 forgets to put in the steam generating container or places the steam generating container without water in the heating chamber 8 in cooking in which the object to be heated is heated by microwaves using steam. Even in such a case, the absence of water for steam generation is determined based on the temperature change of the bottom corner (the place where the steam generation container is placed) in the heating chamber 8 detected by the multi-eye type infrared sensor 9.

  When the determination unit 100b determines that there is no water for generating steam, the heating control unit 100a stops the magnetron 30 and stops cooking, and displays on the display unit 6 that there is no water for generating steam. To inform the user. In addition to displaying on the display unit 6, the user may be notified by synthetic speech that there is no water for generating steam.

  According to the microwave oven of the fifth embodiment, it is possible to detect the absence of water in the steam generating container with a simple configuration. In addition, in the pre-humidification operation in which the steam is previously filled in the heating chamber 8 where there is no object to be heated before cooking, the steam generation container is forgotten to be placed or the steam generation container without water is placed in the heating chamber 8. However, by detecting the absence of water and stopping the microwave, it is possible to prevent the magnetron 30 and the like from being damaged by continuously outputting the microwave in an unloaded state.

  In the fifth embodiment, the water in the steam generating container is heated by microwaves using a multi-eye infrared sensor, and the water temperature is detected. However, a swing type infrared sensor may be used. An infrared sensor that detects only the temperature at the position of the steam generating container may be used.

[Sixth Embodiment]
A microwave oven as an example of the high-frequency heating device according to the sixth embodiment of the present invention will be described. The microwave oven according to the sixth embodiment has the same configuration as that of the microwave oven according to the fifth embodiment except for the operation of the control device 100 (shown in FIG. 12), and FIG. 1, FIG. 2, and FIG. To do.

  In this microwave oven, when a plurality of foods are placed in the heating chamber 8 (shown in FIG. 1) and heated at the same time, the user operates the operation panel 5 (shown in FIG. 1) to adjust the size of the food. In accordance with the above, it is arranged in the heating chamber 8 to input in which region the food is placed, and a set temperature corresponding to each food is input for each region.

  Then, the control device 100 starts heating by the heating control unit 100a, and then detects the temperature for each region obtained by dividing the bottom in the heating chamber 8 detected by the multi-eye infrared sensor 9 (shown in FIG. 5) into a plurality of regions. Based on the above, the position of the food that has reached the set temperature among the plurality of foods is displayed on the display unit 6 (shown in FIG. 1), and the heating control unit 100a once ends the heating.

  The user takes out only the food that has reached the set temperature at the position displayed on the display unit 6 and restarts and repeats the heating, thereby setting a plurality of foods that are heated differently due to differences in size and materials. Can be heated at temperature.

  In the sixth embodiment, the temperature of each region obtained by dividing the bottom of the heating chamber 8 into a plurality of parts is detected using the multi-eye type infrared sensor 9, but an infrared sensor for detecting the temperature of each region is provided. Also good.

[Seventh Embodiment]
FIGS. 13 (a) and 13 (b) are cross-sectional views of a net on which a microwave oven fish as an example of the high-frequency heating device according to the seventh embodiment of the present invention is placed. The microwave oven of the seventh embodiment has the same configuration as that of the microwave oven of the first embodiment except for the mesh 120, and FIGS. 1 and 2 are used.

  In the microwave oven according to the seventh embodiment, as shown in FIG. 13A, for example, a fish is placed on a net 120 and cooked by a heater 110 (shown in FIG. 5).

  The mesh 120 includes a plurality of trapezoidal mesh main bodies 121 provided substantially parallel to each other at intervals, and a plurality of circular cross-sections provided substantially parallel to the net main body 121 in the vicinity of each net main body 121. And a rotating part 122. The plurality of rotating portions 122 are supported so as to be rotatable about a rotation axis parallel to the net body 121.

  During cooking, fish are placed on the plurality of net main bodies 121, and the plurality of rotating portions 122 are at a position lower than the net main body 121.

  When the cooking is finished and the fish is taken out, as shown in FIG. 13 (b), the plurality of rotating portions 122 are simultaneously rotated around the rotation axis O1 by a rotation mechanism (not shown). By doing so, the fish placed on the plurality of net bodies 121 are separated from the plurality of net bodies 121 and placed on the plurality of rotating portions 122.

  In this way, it is possible to cleanly remove the fish stuck to the net body 121 during cooking. Moreover, it is not necessary to gradually pull the stuck fish away from the net, and the take-out time can be shortened.

  In conventional nets on which food is placed, the net is coated with Teflon (registered trademark) in order to improve the peelability of the food, but when exposed to high temperatures, the state of the coating gradually deteriorates and the peelability decreases. For this reason, the food could not be removed cleanly from the net, or it took time to remove the food from the net.

  In contrast, according to the microwave oven of the seventh embodiment, it is possible to quickly separate the cooked food from the net with a simple configuration.

[Eighth Embodiment]
14 (a) and 14 (b) are sectional views of a net on which a microwave oven fish as an example of the high-frequency heating device according to the eighth embodiment of the present invention is placed. The microwave oven according to the eighth embodiment has the same configuration as the microwave oven according to the seventh embodiment except for the mesh 130, and FIGS. 1, 2, and 5 are used.

  In the microwave oven according to the eighth embodiment, as shown in FIG. 14A, for example, a fish is placed on a net 130 and cooked by a heater 110 (shown in FIG. 5).

  The mesh 130 is provided with a plurality of trapezoidal first mesh portions 131 that are substantially parallel to each other with a space between each other, and substantially parallel to the first mesh portion 131 in the vicinity of each first mesh portion 131. A plurality of second net portions 132 having a circular cross section. The plurality of second mesh portions 132 are supported so as to be movable in the vertical direction.

  During cooking, fish are placed on the plurality of first net portions 131, and the plurality of second net portions 132 are located at a lower position than the first net portion 131.

  Then, when cooking is finished and the fish is taken out, as shown in FIG. 14B, a plurality of second nets 132 are simultaneously moved upward by a moving mechanism (not shown), thereby The fish placed on the first net 131 is separated from the plurality of first nets 131 and is placed on the plurality of second nets 132.

  In this way, the fish stuck to the first net 131 during cooking can be taken out cleanly. Moreover, it is not necessary to gradually pull the stuck fish away from the net, and the take-out time can be shortened.

  According to the microwave oven of the eighth embodiment, the cooked food can be quickly separated from the net with a simple configuration.

[Ninth Embodiment]
15 (a) and 15 (b) are sectional views of a net on which a microwave oven fish as an example of the high-frequency heating device according to the ninth embodiment of the present invention is placed. The microwave oven of the ninth embodiment has the same configuration as the microwave oven of the seventh embodiment except for the mesh 140, and FIG. 1, FIG. 2, and FIG.

  In the microwave oven according to the ninth embodiment, as shown in FIG. 15 (a), for example, a fish is placed on a net 140 and cooking is performed by a heater 110 (shown in FIG. 5).

  The mesh 140 is provided with a plurality of trapezoidal first mesh portions 141 that are substantially parallel to each other with a space between each other, and substantially parallel to the first mesh portion 141 in the vicinity of both sides of each first mesh portion 141. And a plurality of second nets 142 having a circular cross section. The plurality of second mesh portions 142 are supported so as to be movable in the vertical direction.

  During cooking, fish are placed on the plurality of first net portions 141, and the plurality of second net portions 142 are located at positions lower than the first net portion 141.

  When the cooking is finished and the fish is taken out, as shown in FIG. 15 (b), a plurality of second nets 142 are simultaneously moved upward by a moving mechanism (not shown), thereby The fish placed on the first net 141 is separated from the plurality of first nets 141 and placed on the plurality of second nets 142.

  In this way, the fish stuck to the first net portion 141 during cooking can be taken out cleanly. Moreover, it is not necessary to gradually pull the stuck fish away from the net, and the take-out time can be shortened.

  According to the microwave oven of the ninth embodiment, it is possible to quickly remove the cooked food from the net with a simple configuration.

  In the seventh to ninth embodiments, the fish placed on the nets 120, 130, and 140 is heated, but food other than fish may be placed on the net.

  Moreover, although the said 7th-9th embodiment demonstrated the microwave oven provided with the magnetron 30 and the heater 110, the high frequency heating apparatus of this invention is a microwave oven which heats a to-be-heated object using a microwave. Applicable.

  Although specific embodiments of the present invention have been described, the present invention is not limited to the first to ninth embodiments, and various modifications can be made within the scope of the present invention.

The high-frequency heating device of this invention is
A magnetron 30 for generating a high frequency for heating an object to be heated;
Inverter circuits 21, 22, 23 for driving the magnetron 30;
An inverter drive circuit 10 for outputting a drive signal to the inverter circuits 21, 22, 23;
An abnormality detection circuit 24 for detecting an abnormal operation of the magnetron 30;
The inverter circuits 21, 22, 23 and the inverter circuit board 20 on which the abnormality detection circuit 24 is mounted,
On the inverter circuit board 20, a conductive pattern 26 for the drive signal from the inverter drive circuit 10 and a conductive pattern 27 for an abnormality detection signal output from the abnormality detection circuit 24 are formed.
The abnormality detection signal conductive pattern 27 and the drive signal conductive pattern 26 have regions close to each other,
Due to the abnormal operation of the magnetron, a high voltage is generated in the conductive pattern 27 for the abnormality detection signal, and a discharge is generated from the conductive pattern 27 for the abnormality detection signal to the conductive pattern 26 for the drive signal in the adjacent region. Thus, the drive signal from the inverter drive circuit 10 is turned off.

  According to the above configuration, in the region where the drive signal conductive pattern 26 and the abnormality detection signal conductive pattern 27 on the inverter circuit board 20 are close to each other, the abnormal operation of the magnetron 30 is performed in a state where the abnormality detection circuit 24 has failed. Thus, the high voltage generated in the abnormality detection signal conductive pattern 27 is applied to the drive signal conductive pattern 26 by discharge. As a result, the high voltage applied to the drive signal conductive pattern 26 destroys the transistor 12 and the like of the inverter drive circuit 10 connected to the drive signal conductive pattern 26 to make the drive signal non-operational. The inverter circuits 21, 22, and 23 are stopped by turning off. Thus, even if the abnormality detection circuit 24 fails, the inverter circuits 21, 22, and 23 can be reliably stopped during the abnormal operation of the magnetron 30.

Moreover, in the high-frequency heating device of one embodiment,
The inverter drive circuit 10 includes a transistor 12 that outputs the drive signal,
In the region where the conductive pattern 27 for the abnormality detection signal and the conductive pattern 26 for the drive signal are close to each other, the conductive pattern for the drive signal is changed from the conductive pattern 27 for the abnormal detection signal by the abnormal operation of the magnetron 30. When the discharge occurs in the transistor 26, the transistor 12 of the inverter drive circuit 10 becomes inoperative.

  According to the embodiment, the high voltage generated in the conductive pattern 27 for the abnormality detection signal due to the abnormal operation of the magnetron 30 in a state where the abnormality detection circuit 24 has failed is applied to the conductive pattern 26 for the drive signal, and the inverter drive circuit Since the transistor 12 that outputs the drive signal 10 is destroyed by a high voltage and becomes non-operational, the inverter circuits 21, 22, and 23 can be more reliably operated when the magnetron 30 operates abnormally even if the abnormality detection circuit 24 fails. Can be stopped.

Moreover, in the high-frequency heating device of one embodiment,
In the region where the abnormality detection signal conductive pattern 27 and the drive signal conductive pattern 26 are close to each other, the abnormality detection signal conductive pattern 27 to the drive signal conductive pattern 26 are caused by the abnormal operation of the magnetron. When the discharge occurs, the drive signal conductive pattern 26 is disconnected by the discharge.

  According to the above embodiment, the high voltage generated in the abnormality detection signal conductive pattern 27 due to the abnormal operation of the magnetron 30 in a state where the abnormality detection circuit 24 has failed is applied to the drive signal conductive pattern 26 to drive the drive signal. As a result, the inverter circuit 21, 22, 23 can be stopped more reliably during abnormal operation of the magnetron 30 even if the abnormality detection circuit 24 fails.

Moreover, in the high-frequency heating device of one embodiment,
The abnormality detection circuit 24 has an anode current detection resistor or a current transformer for detecting the anode current of the magnetron 30.

  According to the above embodiment, when the magnetron 30 operates abnormally when the anode current detection resistor (or current transformer) for detecting the anode current of the magnetron 30 is opened and the abnormality detection circuit 24 fails, the anode current detection resistor is detected. A high voltage is generated from the magnetron 30 in the conductive pattern 27 for the abnormality detection signal connected to the resistor. The high voltage generated in the abnormality detection signal conductive pattern 27 is applied to the drive signal conductive pattern 26 via the discharge portions 26a, 27a, 26b, and 27b to destroy the transistor 12 of the inverter drive circuit 10. The inverter circuits 21, 22, and 23 can be reliably stopped by disconnecting the conductive pattern 26 for driving signals.

DESCRIPTION OF SYMBOLS 1 ... Casing 2 ... Door 3 ... Handle 4 ... Door glass 5 ... Operation panel 6 ... Display part 7 ... Button group 8 ... Heating chamber 9 ... Infrared sensor 10 ... Control board 11 ... Control circuit 12 ... Transistor 20 ... Inverter circuit board 21 ... Control circuit 22 ... Drive circuit 23 ... Repeat detection circuit 24 ... Abnormality detection circuit 26 ... Conductive pattern for drive signal 26a, 26b ... Discharge part 27 ... Conductive pattern for abnormality detection signal 27a, 27b ... Discharge part 30 ... Magnetron 40 ... rear plate 40a ... rear face part 40b ... bottom face part 41 ... deep drawing part 42 ... exhaust port 43 ... exhaust cover 50 ... groove 51 ... groove body 52 ... gap part 55 ... adhesive 60 ... groove 61 ... groove body 62 ... gap part 63 ... Rib 65 ... Adhesive 100 ... Control device 100a ... Heating control unit 100b ... Determination unit 110 ... Heating heater 120 ... Net 121 ... Net body DESCRIPTION OF SYMBOLS 122 ... Turning part 130 ... Net 131 ... 1st net part 132 ... 2nd net part 140 ... Net 141 ... 1st net part 142 ... 2nd net part CN1 ... Connector CN2 ... Connector

Claims (4)

A magnetron that generates a high frequency for heating the object to be heated;
An inverter circuit for driving the magnetron;
An inverter drive circuit for outputting a drive signal to the inverter circuit;
An abnormality detection circuit for detecting abnormal operation of the magnetron;
The inverter circuit and the inverter circuit board on which the abnormality detection circuit is mounted,
A conductive pattern for the drive signal from the inverter drive circuit and a conductive pattern for an abnormality detection signal output from the abnormality detection circuit are formed on the inverter circuit board,
The conductive pattern for the abnormality detection signal and the conductive pattern for the drive signal have regions close to each other,
Due to the abnormal operation of the magnetron, a high voltage is generated in the conductive pattern for the abnormality detection signal, and a discharge is generated from the conductive pattern for the abnormality detection signal to the conductive pattern for the drive signal in the region adjacent to each other. A high-frequency heating apparatus, wherein the drive signal from the inverter drive circuit is turned off. In the high frequency heating apparatus according to claim 1,
The inverter drive circuit includes a transistor that outputs the drive signal,
In the region where the conductive pattern for the abnormality detection signal and the conductive pattern for the drive signal are close to each other, the abnormal operation of the magnetron causes a discharge from the conductive pattern for the abnormality detection signal to the conductive pattern for the drive signal. When this happens, the transistor of the inverter drive circuit becomes inoperative. In the high frequency heating apparatus according to claim 1,
In the region where the conductive pattern for the abnormality detection signal and the conductive pattern for the drive signal are close to each other, the abnormal operation of the magnetron causes a discharge from the conductive pattern for the abnormality detection signal to the conductive pattern for the drive signal. A high-frequency heating apparatus, wherein the drive signal conductive pattern is disconnected by discharge. In the high frequency heating device according to any one of claims 1 to 3,
The high-frequency heating apparatus according to claim 1, wherein the abnormality detection circuit includes an anode current detection resistor or a current transformer for detecting an anode current of the magnetron.

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