JP2005100673A - High-frequency heating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-frequency heating apparatus which has both functions of microwave heating and dielectric heating while assuring prevention of electric discharge and suppression of microwave leakage in a power supply line for supplying high-frequency power to an electrode. <P>SOLUTION: The power supply line 36 for supplying the high-frequency power to the fixed electrode 19 is approximately formed of a coaxial line in a region where the coaxial line penetrates a bottom wall face 13, and while a projection 101 and an insulating member 106 equivalent to an external conductor are arranged inside a heating chamber, a coaxial choke 102 is arranged outside the heating chamber. Hereby, it is possible to prevent the occurrence of discharge caused by high voltage induced in the power supply line 36 in the vicinity of the fixed electrode 19 at the time of dielectric heating, and suppress the leakage of the microwave to the outside of the heating chamber by surely operating the coaxial choke while regulating the transmission direction of the microwave superimposed in the power supply line at the time of microwave heating. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-frequency heating apparatus that can be used in combination with microwave heating and dielectric heating in which an object to be heated is sandwiched between electrodes.

  A microwave oven, which is a representative of a high-frequency heating device, can directly heat an object to be heated, and has become an indispensable device in daily life with the simplicity that does not require preparation of a pot or a pot. In addition, a feature of microwave heating of this microwave oven is that heating energy can be supplied to the inside of the food, and frozen food has been distributed in large quantities by utilizing this feature for thawing frozen food.

  In the microwave oven, the size of the heating chamber for storing the object to be heated is approximately 30 to 40 cm in width and depth, and the height is approximately 20 cm. On the other hand, the wavelength of the microwave used is about 12 cm, and a strong and weak electric field distribution is inevitably generated in the heating chamber. Furthermore, the effect of the shape of the object to be heated and its physical characteristics is synergistic, and local heating occurs. There is. In the thawing of frozen foods, the heating energy is concentrated in the area where the ice melts and becomes water, so that the local heating phenomenon appears prominently, and there is a problem that partial boiling and unthawed coexist.

  The method of performing dielectric heating by using a high-frequency wave having a long wavelength and sandwiching an object to be heated between electrodes has a long history, and the batch method and the belt conveyor method are still used for industrial purposes. These are large-scale apparatus configurations for processing large-scale frozen products and large quantities of frozen products, and the operation of the apparatus is also performed by skilled workers.

  On the other hand, development of a device using this electrode to a home device has been studied for a long time, but it has not yet been possible to provide users with the value of convenience in life or convenience in use.

  This type of conventional high-frequency heating device intended to provide practical value as a household device is used as a turntable on which one of the electrodes used during dielectric heating is used to place an object to be heated during microwave heating. The other electrode is configured to move up and down in the vertical direction (see, for example, Patent Document 1).

According to this Patent Document 1, high-frequency power feeding to an electrode includes a coupling electrode arranged opposite to the electrode, and transmits the high frequency fed to the coupling electrode to the electrode side by capacitive coupling. .
JP-A-9-92455 (Claims, FIG. 1)

  However, in the conventional configuration, the microwave is superimposed on the coupling electrode facing the electrode during microwave heating, and as a result, the microwave leaks out of the heating chamber through the feed line connected to the coupling electrode. have.

  The lower electrode is used as a turntable for placing an object to be heated during microwave heating, and a non-metallic protective material is attached to the surface of the turntable. When heating a large object to be heated with microwave radio waves, such a turntable configuration has a problem that heating of the center of the object to be heated is insufficient.

  The present invention solves the above-mentioned conventional problems, devise the configuration and arrangement of dielectric heating electrodes and high-frequency power feeding to the electrodes, and easy-to-use high-frequency heating during microwave heating and dielectric heating. An object is to provide an apparatus.

  In order to solve the conventional problem, a high-frequency heating device of the present invention includes an electrode that sandwiches an object to be heated in a heating chamber, a high-frequency power source that generates a high frequency, and a power supply line that supplies the high frequency to the electrode. The feeder line has a substantially coaxial line configuration in a region penetrating the wall surface of the heating chamber, a coaxial choke configuration is arranged outside the heating chamber, and an outer conductor of the coaxial line protrudes inside the heating chamber, and the outer conductor An insulating member is extended at the tip of each.

  As a result, the power supply line is insulated from the outer conductor of the substantially coaxial line that has the same potential as the wall surface of the heating chamber, and the occurrence of discharge that tends to occur around the power supply line during dielectric heating is eliminated. In addition, microwaves that are superimposed on the power supply line during microwave heating and leak out of the heating chamber are defined as the direction of the power supply line by the outer conductor protruding into the heating chamber, and the microwave that transmits the power supply line On the other hand, the coaxial choke is reliably operated to suppress the leakage of the microwave to the outside of the heating chamber.

  Since the high-frequency heating device of the present invention can reliably guarantee the prevention of discharge and the suppression of microwave leakage around the power supply line that feeds high-frequency waves to the electrodes, the high-frequency heating device with the respective functions of microwave heating and dielectric heating is provided. Can be provided.

  A first invention is a heating chamber for storing an object to be heated, a microwave generating means for generating a microwave to be supplied to the heating chamber, an electrode for sandwiching the object to be heated in the heating chamber, and a high frequency for generating a high frequency. In the high frequency heating apparatus including a power source and a power supply line for supplying the high frequency to the electrode, the power supply line has a substantially coaxial line configuration in a through portion that penetrates the wall surface of the heating chamber, and a coaxial choke outside the heating chamber. By arranging the configuration so that the outer conductor of the coaxial line protrudes inside the heating chamber and the insulating member extends to the tip of the outer conductor, the feeder line is substantially coaxial with the same potential as the wall surface of the heating chamber. It insulates from the outer conductor of the wire and eliminates the generation of discharge around the feeder line during dielectric heating. In addition, microwaves that are superimposed on the power supply line during microwave heating and leak out of the heating chamber are defined as the direction of the power supply line by the outer conductor protruding into the heating chamber, and the microwave that transmits the power supply line On the other hand, the coaxial choke is reliably operated to suppress the leakage of the microwave to the outside of the heating chamber. In addition, since it is possible to reliably ensure prevention of discharge and suppression of microwave leakage around the power supply line that supplies high frequency to the electrode, it is possible to provide a high-frequency heating device having functions of microwave heating and dielectric heating.

  In the second invention, in particular, the impedance between the electrodes sandwiching the object to be heated is provided by disposing the through portion of the heating chamber wall surface of the power supply line of the first invention outside the heating chamber wall surface facing the electrode surface. The strength of the high-frequency electric field supplied to the electrode varies depending on the position of the feed-line at the through-portion by placing the penetrating part at a position that avoids the influence of the change in the high-frequency electric field generated between the electrode and the heating chamber wall surface Insulating properties can be guaranteed.

  In the third invention, in particular, the substantially coaxial line configuration of the power supply line of the first invention is provided with at least an elastic insulating member, so that the power supply line expands due to heat generation of the power supply line due to high-frequency loss. Insulation performance can be maintained.

  In the fourth invention, in particular, the electrode of the first invention is composed of a fixed electrode and a movable electrode, and includes a mounting plate made of a dielectric material on which an object to be heated is mounted, and the fixed electrode is provided below the mounting plate. By providing the above, it is possible to provide a device that is easy to use as long as the object to be heated is placed in the same manner for microwave heating and dielectric heating. If this fixed electrode is a high-voltage side electrode, the fixed electrode is not touched, and safety can be ensured.

  In the fifth invention, in particular, by providing a plurality of openings in the heating chamber wall faced by the fixed electrode of the fourth invention, the capacitance component generated between the fixed electrode and the heating chamber wall surface is reduced, Reactive power can be reduced and the object to be heated can be efficiently dielectrically heated.

  According to the sixth aspect of the invention, in particular, the fixed electrode of the fourth aspect of the invention has an opening at a substantially central portion thereof, and the periphery of the opening is formed in a convex shape on the movable electrode side. The high frequency electric field can be strengthened by shortening the distance between the electrodes by the convex portion against the weakening of the high frequency electric field between the electrodes, and the dielectric heating of the heated object facing the opening can be promoted.

  According to the seventh aspect of the invention, in particular, the aperture of the fixed electrode of the sixth aspect of the invention has a diameter that is about 1/4 or more of the wavelength of the microwave. Thus, the microwave can be sufficiently supplied to the portion of the object to be heated that faces the opening, and the heating of the object to be heated can be made uniform.

  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 is a front sectional view of a high-frequency heating device showing a state during dielectric heating in the first embodiment of the present invention, FIG. 2 is a sectional configuration view seen from the right side of FIG. 1, and FIG. FIG. 4 is a configuration diagram of the fixed electrode of FIG. 1.

  1 to 4, a heating chamber 10 that accommodates an object to be heated includes a left wall surface 11, a right wall surface 12, a bottom wall surface 13, an upper wall surface 14, and a back wall surface, which are boundary surfaces of a metal material that can confine microwaves. 15 and an opening / closing door 16 having a punching plate through which the heating chamber can be seen through, and a mounting plate 18 made of a dielectric material on which the object to be heated 17 is mounted is disposed in the heating chamber 10. A fixed electrode 19 that is one electrode for dielectric heating is disposed below the mounting plate 18, and a movable electrode 20 that is the other electrode is disposed above the mounting plate 18, and the movable electrode 20 slides. However, it is configured to move vertically. A radio wave radiation means 21 that radiates microwaves is disposed below the fixed electrode 18. The waveguide 22 has a magnetron 23 which is a microwave generating means arranged on one end side, transmits the microwave generated by the magnetron 23 and guides it to the radio wave radiating means 21 arranged on the other end side. The rotation axis of the radio wave radiation means 21 is inserted into the waveguide 22. The motor 24 has an output shaft that fits with the rotating shaft of the radio wave radiating means 21, and the radio wave radiating means 21 is rotated by operating the motor 24. The radio wave radiation means 21 has a disk configuration having an opening, and is configured such that the radio wave radiation direction or radiation distribution changes with rotation. The radio wave radiating means 21 may be configured as a long plate, a waveguide antenna, or the like.

  The fixed electrode 19 is provided with an opening 19a having a diameter of 1/4 or more of the wavelength of the microwave at a substantially central portion (corresponding to a substantially central portion in the left and right and front and rear directions of the heating chamber), and the periphery of the opening 19a. The part has a configuration in which a convex processing 19b is applied to the movable electrode 20 side.

  The diameter of the opening 19a is preferably 31 mm or more when using a microwave of 2450 MHz band, and is selected to be 50 mm or less at the maximum. Further, the height of the convex portion around the opening is about 3 mm with respect to the plane of the fixed electrode 19.

  The distances G1 and G2 between the fixed electrode 19 and the wall surface of the heating chamber are at least 1/4 or more of the wavelength of the microwave used.

  On the other hand, the peripheral part of the movable electrode 20 is configured closer to the wall surface side of the heating chamber than the peripheral part of the fixed electrode 19 (corresponding to W1 in FIG. 1 and W2 in FIG. 2). Two movable shafts 26 and 27 are assembled to the movable electrode 20 via a support portion 25. These two rotary shafts 26 and 27 are configured so as to be freely rotatable in the through holes provided in the support portion 25, respectively, and are movable in the lifting and lowering operation of the movable electrode 20 accompanying the rotation of the rotary shafts 26 and 27. The electrode 20 moves up and down substantially parallel to the fixed electrode 19. One rotating shaft 27 is provided with an elastic metal wire 28. One end of the metal wire 28 is connected to the movable electrode 20, and the other end is fixed to the rotating shaft 27 by welding. The movable electrode 20 is electrically connected to the metal wall surface of the heating chamber 10 through the metal wire 28 and the rotating shaft 27. The motor 29 rotates the rotary shafts 26 and 27. In addition, by using a drive system configured with a plurality of gears or the like for this rotational drive, the load on the motor 29 can be reduced and a small motor can be used. The rotary shafts 26 and 27 are rotatably supported by penetrating the wall surface of the heating chamber 10, and a radio wave seal mechanism 30 is disposed on each of the support portions.

  Further, the fixed electrode 19 is supported by a support column 32 made of an insulating material with a predetermined gap from the bottom wall surface 13 of the heating chamber so as to be disposed close to the lower surface of the mounting plate 18.

  The high frequency power source 33 generates a high frequency (for example, 13.56 MHz, 27.12 MHz) to be supplied to each electrode. The power detector 34 detects incident power transmitted from the high-frequency power source 33 in the direction of the electrode and reflected power returning from the electrode side to the high-frequency power source side (such as a CM type SWR circuit). The matching circuit 35 has a circuit configuration of a coil connected in series to an electrode and a capacitor connected in parallel, and at least the coil has a configuration in which the impedance of the coil can be continuously changed. To match. The high-voltage side of the matching circuit 35 is connected to the fixed electrode 19, and the ground side is connected to the wall surface of the heating chamber 10. The high-voltage power supply line 36 has a substantially coaxial line configuration 37 (details will be described later with reference to FIG. 3) in a region penetrating the wall surface of the heating chamber 10.

  Based on the detection signal of the power detection unit 34, the control unit 38 performs variable control of the output of the high frequency power supply 33, the values of the coils and capacitors of the matching circuit 35, or operation control of the motor 29. 2 indicates the apparatus main body 39.

  Next, a configuration around the feeder line 36 that feeds a high frequency to the fixed electrode 19 will be described. The feed line 36 has a heating chamber bottom wall surface 13 as a through wiring, and the through region has a substantially coaxial line configuration. That is, in FIG. 3, the heating chamber bottom wall surface 13 forms a protruding portion 101 corresponding to an external conductor by drawing processing inside the heating chamber. A coaxial choke 102 is disposed outside the heating chamber bottom wall surface 13. The coaxial choke 102 includes a first structure 103 and a second structure 104. These first and second structures 103 and 104 are each configured with a predetermined inner diameter and length so that the impedance at the cut 105 of the outer conductor of the coaxial line becomes substantially infinite in the microwave frequency band to be used. It is configured. The coaxial choke 102 is welded (or screwed) to the heating chamber bottom wall surface 13.

  The power supply line 36 passes through the coaxial choke 102 and the protruding portion 101 and is wired substantially concentrically with respect to the coaxial choke 102 and the protruding portion 101 via an insulating member. As this insulating member, an elastic insulating member 106 and a molded non-elastic insulating member 107 are used, and the elastic insulating member 106 (for example, a silicon rubber tube) is disposed inside. The inelastic insulating member 107 is further extended from the tip of the protruding portion 101. Further, the through portion of the heating chamber wall surface of the power supply line 36 is disposed outside the facing region of the heating chamber bottom wall surface 13 where the fixed electrode 19 faces. Thereby, the other end of the power supply line 36 is bent to approximately 90 degrees and is assembled and connected to the fixed electrode 19 by the screw 108.

  As a configuration example of the coaxial choke, the first structure 103 has an inner diameter of 15.5 mm, a length of 10.0 mm, a plate thickness of 0.5 mm, and the second structure 104 has an inner diameter of 8.5 mm on the inner side. The length is 13.5 mm, the plate thickness is 0.5 mm, and the outside has an inner diameter of 27.5 mm, a length of 16.5 mm, and a plate thickness of 0.5 mm. The protruding portion 101 has an inner diameter of 8.5 mm, a length of 6 mm, the length of the insulating member 107 from the tip of the protruding portion 101 is 6 mm, and the feeder line 36 has a diameter of 3 mm.

  In addition, a plurality of apertures 13 a are provided in the heating chamber bottom wall surface 13 facing the fixed electrode 19. The opening 13a functions as a leakage prevention structure for microwaves, and as an example, a hole having a diameter of 3 mm is arranged with an opening ratio of about 50%. In the region corresponding to the tube wall surface of the waveguide 22, holes having a diameter of 2 mm of the opening 13a are arranged with an opening ratio of about 40%.

  In the configuration as described above, the power supply line 36 has a double insulation configuration with respect to the outer conductor, and the insulation member 107 is interposed between the protruding portion 101 and the power supply near the fixed electrode 19 during dielectric heating. The occurrence of discharge due to the high voltage generated in the electric wire 36 is eliminated. For microwaves that are superimposed on the power supply line during microwave heating and are going to leak out of the heating chamber, the transmission direction is defined as the direction of the power supply line by the external conductor protruding into the heating chamber, and the power supply line is transmitted. A coaxial choke is reliably applied to the microwave to suppress leakage of the microwave to the outside of the heating chamber. In addition, since it is possible to reliably ensure prevention of discharge and suppression of microwave leakage around the power supply line that supplies high frequency to the electrode, it is possible to provide a high-frequency heating device having functions of microwave heating and dielectric heating.

  In addition, by arranging the through portion of the heating chamber wall surface of the power supply line 36 outside the heating chamber wall surface facing the electrode surface, the high-frequency electric field strength supplied to the electrode by the impedance between the electrodes sandwiching the object to be heated is Although it changes, a penetration part can be arrange | positioned in the position which avoided the influence of the change of the high frequency electric field produced between the electrode and heating chamber wall surface in connection with it, and the insulation of the feeder in a penetration part can be ensured.

  In addition, since at least an elastic insulating member 106 is provided in the substantially coaxial line constituent portion of the power supply line 36, insulation performance against linear expansion of the power supply line 36 due to heat generation of the power supply line 36 due to high frequency loss is provided. Can be maintained.

  Further, by providing the radio wave radiation means 21 below the fixed electrode 19, microwaves are radiated from below the object to be heated in the same direction as the electric field generated between the electrodes in dielectric heating. The heated object can be placed in a shared configuration without a turntable (mounting plate 18 structure), and the heated object can be placed in the same manner for microwave heating and dielectric heating. A good device can be provided. Further, if the fixed electrode 19 is a high-voltage side electrode, the structure does not touch the fixed electrode, and safety can be ensured.

  Further, by providing a plurality of apertures 13a in the heating chamber wall surface 13 to which the fixed electrode 19 opposes, the capacitance component generated between the fixed electrode 19 and the heating chamber wall surface 13 is reduced, and the reactive power is reduced. The object to be heated can be efficiently dielectrically heated.

  In addition, the opening 19a provided in the central portion of the fixed electrode 19 has a substantially circular shape, and the diameter of the opening 19a is not less than 1/4 of the wavelength of the microwave to be used. Therefore, it is possible to sufficiently supply the microwave to the portion of the object to be heated that faces the opening 19a, and it is possible to more reliably guarantee the uniform heating of the object to be heated during the microwave heating. It should be noted that by setting the opening 19a to a maximum of 50 mm or less, it is possible to suppress a region where no high frequency electric field exists at the center of the electrode during dielectric heating.

  Further, by forming at least the periphery of the opening 19a of the fixed electrode 19 in the convex shape 19b on the movable electrode side, the distance between the electrodes is shortened by the convex portion against the weakening of the high-frequency electric field between the electrodes due to the presence of the opening 19a. Thus, the high frequency electric field can be strengthened, and the dielectric heating of the object to be heated facing the opening 19a can be promoted. Further, by performing this convex processing 19b, the mechanical strength of the fixed electrode 19 can be increased and the occurrence of thermal strain can be suppressed.

  In addition, the distance between the fixed electrode 19 and the wall surface of the heating chamber is at least 1/4 or more of the wavelength of the microwave to be used, so that the microwave can be evenly distributed from the periphery of the fixed electrode 19 to the heated object side. It is possible to make the heating of the object to be heated uniform.

  Further, the peripheral part of the movable electrode 20 gives the user a sense of security that the storage position of the object to be heated is wide by adopting a configuration closer to the wall surface side of the heating chamber than the peripheral part of the fixed electrode 19, A user-friendly device can be provided by reducing the concentration of the electric field distribution at the end portion around the electrode.

  Furthermore, the movable electrode 20 moves up and down while sliding, not simply moving up and down. And it is set as the structure accommodated directly under the upper wall surface 14. FIG. During this up and down operation, the movable electrode 20 is operated so as to vary the facing interval while facing the fixed electrode 19 substantially in parallel, thereby adjusting the facing interval according to the thickness of the object to be heated. It is possible to maximize the dielectric heating energy supplied to the object to be heated and to perform heating for a short time.

  Next, the operation of the control unit 38 during dielectric heating will be described.

  After the object to be heated is stored, when the dielectric heating start key is pressed, the motor 29 is operated to lower the movable electrode 20 and set it at a position having a predetermined gap from the object to be heated. Thereafter, the high frequency power supply 33 is operated with a low power output of about 50 W, and the matching circuit is operated so as to minimize the reflected power obtained from the power detection unit 34. After the reflected power is minimized, the output of the high frequency power supply 33 is maximized, and the object to be heated is dielectrically heated. Even during this heating, the detection signal from the power detection unit 34 is taken in at any time, and the operation of the matching circuit 35 (or the motor 29) is controlled so that the reflected power is minimized. Thereafter, when the end time of the dielectric heating comes due to the elapse of a predetermined heating time or the heating end time determination based on the signal change of the power detection unit, the operation of the high frequency power supply 33 is stopped, the motor 29 is operated, and the movable electrode 20 is operated. Is moved up and stored immediately below the upper wall surface 14 of the heating chamber.

  Note that it is desirable to convection or supply / exhaust air in the heating chamber 10 during dielectric heating.

  Next, main operations in the case of microwave heating will be described. In the case of microwave heating, the movable electrode 20 performs heating while being housed immediately below the upper wall surface 14 of the heating chamber.

  After the object to be heated is placed on the placing plate 18, the door 16 is closed, the heating condition is input using the operation keys in the operation panel (not shown), and the heating start key is pressed. Wave heating starts. When recognizing that the heating start key has been pressed, a control unit (not shown) incorporated in the apparatus operates a power source (not shown) that drives the magnetron 23. As a result, the magnetron 23 generates microwaves. The generated microwave is transmitted through the waveguide 22, supplied to the radio wave radiation means 21 provided on the terminal end side of the waveguide 22, and radiated into the heating chamber 10. The microwave radiated here passes through the gap 19 between the peripheral edge of the fixed electrode 19 and the wall surface of the heating chamber and the opening 19 a provided in the center of the fixed electrode 19, passes through the mounting plate 18, and is applied to the object to be heated. Wave energy is supplied to uniformly heat the object to be heated.

  Next, main operations in the case of using both dielectric heating and microwave heating will be described.

  Such heating includes “thawing warming” of frozen food. For “thaw and warm”, first, dielectric heating is performed, and then microwave heating is performed. The operation at the time of delivery of each heating method will be described. As the dielectric heating ends, the operation of the high-frequency power source 33 is stopped and the movable electrode 20 is moved up and directly below the upper wall surface 14. Immediately thereafter, the magnetron 23 is operated to complete the transition to microwave heating.

  Since the high-frequency electric field generated between the opposing electrodes penetrates the frozen food, the temperature of the frozen food is surely increased to the inside of the food, so that the food is uniformly thawed. By performing microwave heating from this state, the thawed food can suppress consumption of heat energy for melting, and the whole food is heated to a desired appropriate temperature in a short time.

  An example of the dimensions of the heating chamber and the electrodes used in Embodiment 1 of the present invention is that the heating chamber has a width of 415 mm, a depth of 315 mm, a height of 230 mm, and the fixed electrode 19 has a width of 280 mm, a depth. The shape of the movable electrode 20 is 200 mm wide, the depth is 220 mm, and the gap between the fixed electrode 19 and the heating chamber wall surface 13 is 30 mm.

  As described above, since the high-frequency heating device according to the present invention can be used in combination with microwave heating and dielectric heating, it can be used for food heating, thawing device, ceramic heating device, drying device, biochemical reaction device, and the like. Applicable.

Front sectional view at the time of dielectric heating of the high-frequency heating device of Embodiment 1 of the present invention Sectional view seen from the right side of the high-frequency heating device Configuration diagram of a substantially coaxial line configuration of the feed line of the high-frequency heating device Configuration diagram of lower electrode of the same high-frequency heating device

Explanation of symbols

10 Heating chamber 13a Multiple openings (openings on the wall of the heating chamber)
17 object to be heated 18 mounting plate 19 fixed electrode 19a opening 19b convex 20 movable electrode 23 magnetron (microwave generating means)
33 High-frequency power supply 36 Feed line 101 Projection (projection of external conductor)
102 Coaxial choke 106 Elastic insulating member 107 Insulating member

Claims (7)

A heating chamber for storing an object to be heated; microwave generation means for generating a microwave to be supplied to the heating chamber; an electrode for sandwiching the object to be heated in the heating chamber; a high-frequency power source for generating a high frequency; A high-frequency heating device including a power supply line for supplying power to the electrode, wherein the power supply line has a substantially coaxial configuration at a penetration portion that penetrates the wall surface of the heating chamber, and is disposed outside the heating chamber of the penetration portion. A high-frequency heating apparatus having a configuration in which a coaxial choke is arranged, an outer conductor of a coaxial line is projected on the heating chamber side of the penetrating portion, and an insulating member is extended to a tip of the outer conductor. The high-frequency heating device according to claim 1, wherein the penetrating portion is disposed outside a heating chamber wall surface facing the electrode surface. The high-frequency heating device according to claim 1, wherein at least an insulating member of an elastic body is disposed in the substantially coaxial line configuration of the power supply line. The high-frequency heating device according to claim 1, wherein the electrode includes a fixed electrode and a movable electrode, and includes a mounting plate made of a dielectric material on which an object to be heated is mounted, and the fixed electrode is provided below the mounting plate. The high frequency heating device according to claim 4, wherein a plurality of apertures are provided in a wall surface of the heating chamber facing the fixed electrode. The high-frequency heating device according to claim 4, wherein the fixed electrode is provided with an opening at a substantially central portion thereof, and a periphery of the opening is formed in a convex shape toward the movable electrode. The high-frequency heating device according to claim 6, wherein the opening of the fixed electrode has a size having a diameter of approximately ¼ or more of the wavelength of the microwave.

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