WO2020079811A1

WO2020079811A1 - Induction heater

Info

Publication number: WO2020079811A1
Application number: PCT/JP2018/038853
Authority: WO
Inventors: 平和田; 暁人平井; 英悟桑田; 和宏弥政
Original assignee: 三菱電機株式会社
Priority date: 2018-10-18
Filing date: 2018-10-18
Publication date: 2020-04-23

Abstract

An induction heater (1), wherein matter to be heated (6) is fed between an electrode (3) and an electrode (4) by a capillary phenomenon, and the matter to be heated (6), fed between the electrode (3) and the electrode (4), is heated by an electric field produced between the grounded electrode (4) and the electrode (3) to which a high-frequency signal is applied from a signal source (2).

Description

Dielectric heating device

The present invention relates to an induction heating device.

For example, Patent Document 1 describes a device for heating and drying wood from the inside by applying a high frequency between a pair of electrodes sandwiching wood, which is an object to be heated. In this device, each of the pair of electrodes has a flat plate shape, and one electrode almost covers one surface of the wood. Therefore, by applying a high frequency between the electrodes, the whole wood is uniformly heated.

JP 2004-195931 A

When the object to be heated is a liquid and the liquid is vaporized by dielectric heating, the liquid may be uniformly heated by using a flat plate-shaped electrode like the conventional device described in Patent Document 1. There was a problem that it takes a long time to be vaporized.

The present invention solves the above problems, and an object of the present invention is to obtain an inductive heating device that can shorten the heating time required for the object to be vaporized.

The dielectric heating device according to the present invention includes a signal source of a high frequency signal, a first electrode connected to the signal source, and a second electrode which is arranged to face the first electrode and is grounded, An object to be heated is supplied between the first electrode and the second electrode by a capillary phenomenon, and is generated between the first electrode to which a high frequency signal is applied from the signal source and the grounded second electrode. The object to be heated supplied between the first electrode and the second electrode is heated by the generated electric field.

According to the present invention, the object to be heated is supplied between the first electrode and the second electrode by the capillary phenomenon, and the first electric field is generated by the electric field generated between the first electrode and the second electrode. The object to be heated supplied between the electrode and the second electrode is heated. Since the object to be heated is intensively heated between the first electrode and the second electrode, the heating time required for the object to be heated to vaporize can be shortened.

FIG. 3 is a perspective view showing a configuration example of the dielectric heating device according to the first embodiment. FIG. 3 is a front view showing a configuration example of the dielectric heating device according to the first embodiment. It is a graph which shows the relationship between the cross-sectional area of the space where the to-be-heated object moves by a capillary phenomenon, and the height of the liquid level of the to-be-heated object. It is a top view which shows the modification of the dielectric heating apparatus which concerns on Embodiment 1. It is a perspective view which shows the structural example of the dielectric heating apparatus which concerns on Embodiment 2. It is a top view which shows the structural example of the dielectric heating apparatus which concerns on Embodiment 2. It is a perspective view which shows the structural example of the dielectric heating apparatus which concerns on Embodiment 3. It is a top view which shows the electric force line formed by the electric field generated between two electrodes arrange | positioned in parallel. It is a top view which shows the electric force line formed by the electric field generated between three electrodes arrange | positioned in parallel. It is a top view which shows the electric force line formed by the electric field generated between two electrodes arranged concentrically. It is a perspective view which shows the structural example of the dielectric heating apparatus which concerns on Embodiment 4. It is a front view which shows the structural example of the dielectric heating apparatus which concerns on Embodiment 4.

Embodiment 1.
FIG. 1 is a perspective view showing a configuration example of the dielectric heating device 1 according to the first embodiment. As shown in FIG. 1, the dielectric heating device 1 includes a signal source 2, an electrode 3, an electrode 4 and a container 5, and heats an object 6 to be heated by inductive heating to be vaporized. Dielectric heating is a phenomenon in which electric dipoles inside a dielectric, which is the object 6 to be heated, rotate due to a high-frequency electric field, and the rotated electric dipoles cause friction to generate heat inside the dielectric.

Also, in dielectric heating, the phenomenon in which part of the electrical energy applied to the dielectric is converted into heat energy and dissipated is called dielectric loss. A member having a small dielectric loss is rarely heated by a high frequency electric field, and a member having a large dielectric loss is easily heated by a high frequency electric field.

The signal source 2 is a signal source that generates a high frequency signal, and has an output terminal a that outputs the high frequency signal and a ground terminal b of 0 potential. The high frequency signal generated by the signal source 2 is output to the electrode 3 via the output terminal a. The ground terminal b of the signal source 2 may be connected to the ground (0 potential) of the dielectric heating device 1.

For the signal source 2, any one of a crystal oscillator, a rubidium oscillator, a voltage controlled oscillator (VCO), a direct digital synthesizer (DDS), and a phase lock loop (PLL) circuit capable of outputting a signal of an arbitrary frequency is used. May be. However, the oscillator used for the signal source 2 may have any configuration as long as it can generate a high-frequency signal. The high-frequency signal output from the signal source 2 may be a sine wave, a rectangular wave, a continuous wave (CW) signal, or a modulated signal. .

The electrode 3 is a first electrode connected to the output terminal a of the signal source 2, and the electrode 4 is a second electrode arranged so as to face the electrode 3. The electrode 4 is connected to the ground terminal b of the signal source 2 and grounded. When the high frequency signal generated by the signal source 2 is applied to the electrode 3 via the output terminal a, a high frequency electric field is generated between the electrode 3 and the electrode 4. A metal flat plate may be used for the

electrodes

3 and 4, for example.

The material forming the

electrodes

3 and 4 may be any material that can generate a high-frequency electric field between the

electrodes

3 and 4, and a plurality of materials may be used. The

electrodes

3 and 4 function as capacitors, and the object 6 to be heated is supplied between the

electrodes

3 and 4 by a capillary phenomenon. The object 6 to be heated may be any liquid that can be moved by a capillary phenomenon, and examples thereof include water and tobacco liquid.

The container 5 is a container for holding the object 6 to be heated. The

electrodes

3 and 4 are connected to the container 5 and their positions are fixed. For example, the distance between the

electrodes

3 and 4 is constant, and the objects to be heated 6 are supplied only from the bottom surface side of the container 5 between the

electrodes

3 and 4, so that the outer surfaces of the

electrodes

3 and 4 are The wall surface of the container 5 is connected.

Glass may be used as the material of the container 5, for example. In addition, although the rectangular parallelepiped container 5 is shown in FIG. 1, it is not limited to this. If the container 5 holds the article to be heated 6 without leaking, the

electrodes

3 and 4 are not short-circuited, and can withstand the heat generated between the

electrodes

3 and 4, the material and shape of the container 5 are It doesn't matter. Also, a plurality of materials may be used for the container 5.

FIG. 2 is a front view showing a configuration example of the dielectric heating device 1 according to the first embodiment. In FIG. 2, the front surface of the container 5 is transparent so that the inside of the container 5 can be visually recognized. The liquid level of the object to be heated 6 supplied between the

electrodes

3 and 4 is higher than the liquid level of the object to be heated 6 held in the container 5. That is, the object to be heated 6 moves from the container 5 in the direction indicated by the solid arrow in FIG. 2 by the capillary phenomenon and is supplied between the electrode 3 and the electrode 4. In FIG. 2, the height h indicates the height of the liquid surface of the object to be heated 6 which is supplied from the container 5 between the

electrodes

3 and 4 and rises due to the capillary phenomenon.

For example, when the object 6 to be heated rises due to the capillary phenomenon in the tube formed by being surrounded by the walls of the

electrodes

3, 4 and the container 5, the height h of the liquid surface of the object 6 to be heated is It can be represented by (1). In the following formula (1), ρ is the density of the object to be heated 6, T is the surface tension of the object to be heated 6, g is the gravitational acceleration, S is the cross-sectional area of the pipe, and L is the length of the outer circumference of the cross-section of the pipe. Is the contact angle between the object 6 to be heated and the inner wall of the tube.
h = TLcos θ / ρgS (1)

In the above formula (1), when the cross-sectional shape of the tube is a square with a cross-sectional area S, L = S ^1/2, and therefore the relation of the following formula (2) is established.
h = Tcos θ / ρgS ^1/2 (2)

FIG. 3 is a graph showing the relationship between the cross-sectional area S of the tube, which is the space in which the object to be heated 6 moves due to the capillary phenomenon, and the height h of the liquid surface of the object to be heated 6, where the horizontal axis represents S and the vertical axis represents S. The axis is h. In FIG. 3, ρ, g, T, and θ are assumed to be constant values regardless of the value of the cross-sectional area S. S _A is the minimum value of the cross-sectional area S at which the capillary phenomenon does not occur. From the above formula (2), when the cross-sectional area S of the tube is S _A or more (S ≧ S _A ), the capillary phenomenon does not occur, and the heated object 6 does not rise in the tube, so h = It becomes 0.

On the other hand, if the cross-sectional area S of the tube is less than S _A (S <S _A ), the capillary phenomenon occurs and the article 6 to be heated rises in the tube. At this time, the smaller the cross-sectional area S of the pipe, the larger the value of h. Assuming that the area of the liquid surface of the object 6 to be heated in the container 5 is S _B , the cross-sectional area S (S <S _A ) of the tube where the capillary phenomenon occurs is generally a value sufficiently smaller than the area S _B. Become. For example, when the cross-sectional area S of the tube in which the capillary phenomenon occurs is 1/10 or less of the area S _B , the object 6 to be heated is supplied to the tube by the capillary phenomenon. Note that the strict area S _B is an area obtained by removing the cross-sectional area S of the pipe from the area of the liquid surface of the object 6 to be heated in the container 5.

By sufficiently narrowing the interval between the

electrodes

3 and 4 and reducing the cross-sectional area S of the tube, the object to be heated 6 is supplied between the

electrodes

3 and 4 by the capillary phenomenon, and the object to be heated 6 is heated. The height h of the liquid surface becomes larger than zero. When the high frequency signal generated by the signal source 2 is applied to the electrode 3 in the state where the object 6 to be heated is present between the electrode 3 and the electrode 4, a high frequency electric field is generated between the electrode 3 and the electrode 4. It is generated and the object 6 to be heated is heated. Since the distance between the

electrodes

3 and 4 is narrow and the cross-sectional area S of the tube is small, the volume of the object to be heated 6 existing between the

electrodes

3 and 4 is very small. That is, in the dielectric heating device 1, a part of the object 6 to be heated held in the container 5 is intensively heated between the

electrodes

3 and 4. As a result, the heating time required for the heated object 6 to vaporize can be shortened.

For example, the vaporized object to be heated 6 is discharged in the direction indicated by the dashed arrow in FIG. 2, so that the object to be heated 6 existing between the

electrodes

3 and 4 is reduced. At this time, in the dielectric heating device 1, the object 6 to be heated is continuously supplied from the container 5 between the

electrodes

3 and 4 by a capillary phenomenon so as to compensate for the released amount. Thereby, the heating and vaporization of the object 6 to be heated can be continued between the

electrodes

3 and 4.

Next, a modification of the dielectric heating device 1 according to the first embodiment will be described.
FIG. 4 is a top view showing a dielectric heating device 1A which is a modification of the dielectric heating device 1. In FIG. 4, description of the signal source 2, the wiring that connects the signal source 2 and the electrode 3A, and the wiring that connects the signal source 2 and the electrode 4A is omitted. The dielectric heating device 1A includes an electrode 3A and an electrode 4A, and the

electrodes

3A and 4A are square pole-shaped electrodes.

In the dielectric heating device 1, by narrowing the gap between the electrode 3 and the electrode 4, a cross-sectional area S in which a capillary phenomenon occurs is secured. On the other hand, the dielectric heating device 1A secures the cross-sectional area S in which the capillary phenomenon occurs by narrowing the distance between the wall surface 5A-1 and the wall surface 5A-2 of the container 5A. Even with such a configuration, the object to be heated 6 is supplied to the space surrounded by the front wall surface 5A-1 and the rear wall surface 5A-2 of the electrode 3A, the electrode 4A, and the container 5A by a capillary phenomenon. As a result, the object to be heated 6 existing between the electrode 3A and the electrode 4A is intensively heated, so that the heating time required for the object to be heated 6 to vaporize can be shortened.

As described above, the dielectric heating device 1 according to the first embodiment includes the signal source 2, the electrode 3, and the electrode 4, and the object 6 to be heated is supplied between the electrode 3 and the electrode 4 by the capillary phenomenon. The object 6 to be heated supplied between the

electrodes

3 and 4 is heated by the electric field generated between the

electrodes

3 and 4. Since the object 6 to be heated supplied between the electrode 3 and the electrode 4 is intensively heated, the heating time required for the object 6 to be vaporized to be vaporized can be shortened. Similar effects can be obtained in the dielectric heating device 1A shown in FIG.

In the dielectric heating device 1 according to the first embodiment, the liquid level of the heated object 6 supplied between the electrode 3 and the electrode 4 is higher than the liquid level of the heated object 6 held in the container 5. In this state, the object to be heated 6 in the container 5 is continuously supplied between the

electrodes

3 and 4 by a capillary phenomenon so as to compensate for the amount of the object to be heated 6 vaporized by heating. Thereby, the heating and vaporization of the object 6 to be heated can be continued between the

electrodes

3 and 4. Similar effects can be obtained in the dielectric heating device 1A shown in FIG.

In the dielectric heating device 1 according to the first embodiment, the cross-sectional area S of the portion where the capillary phenomenon occurs between the electrode 3 and the electrode 4 is 10 minutes of the area S _B of the liquid surface of the object 6 to be heated in the container 5. Is less than or equal to 1. With this configuration, the object 6 to be heated can be supplied between the

electrodes

3 and 4 by the capillary phenomenon.

Embodiment 2.
FIG. 5 is a perspective view showing a configuration example of the dielectric heating device 1B according to the second embodiment. 5, the same components as those of FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. x is the height of the

electrodes

3 and 4. A partition member 7 is arranged between the electrode 3 and the electrode 4 included in the dielectric heating device 1B. The partition member 7 is a flat plate-shaped member, as shown in FIG.

The partition member 7 has a smaller dielectric loss than the object 6 to be heated, does not short-circuit the

electrodes

3 and 4, and can withstand the heat generated between the

electrodes

3 and 4. It is configured. The material forming the partition member 7 may be a material through which the article 6 to be heated permeates, or a plurality of materials may be used. Further, although the plate-shaped partition member 7 is shown in FIG. 5, the partition member 7 may have any shape as long as it can reduce the volume occupied by the article 6 to be heated between the

electrodes

3 and 4. It may have a shape other than a flat plate.

FIG. 6 is a top view showing a configuration example of the dielectric heating device 1B, and description of the signal source 2, the wiring connecting the signal source 2 and the electrode 3, and the wiring connecting the signal source 2 and the electrode 4 is omitted. are doing. In FIG. 6, the

electrodes

3 and 4 are metal parallel plates, and the container 5 is a rectangular parallelepiped glass container. The partition member 7 is a glass prismatic member. The dielectric loss of the partition member 7 is sufficiently smaller than the dielectric loss of the object 6 to be heated and can be ignored with respect to the dielectric loss of the object 6 to be heated. The object to be heated 6 and air exist inside the container 5.

The

electrodes

3 and 4 are parallel flat plates having a height x and a width 2d, and the distance between the

electrodes

3 and 4 is d. The partition member 7 has a square prismatic shape with a height x and a vertical and horizontal dimensions of d. Here, when the partition member 7 is not arranged between the electrode 3 and the electrode 4, the height h of the liquid surface of the object to be heated 6 supplied between the electrode 3 and the electrode 4 by the capillary phenomenon is It can be expressed by the following formula (3).
h = 3T cos θ / ρgd (3)

Since the cross-sectional area of the tube surrounded by the front wall surface and the rear wall surface of the electrode 3, the electrode 4, and the container 5 is 2d ² , the volume of the object to be heated 6 that has risen in the tube due to the capillary phenomenon is Vd. In this case, the volume V can be expressed by the following formula (4).
V = 2d ² h = 6d Tcos θ / ρg (4)

When the permittivity of the object to be heated 6 is ε, the voltage applied between the

electrodes

3 and 4 is v, and the energy stored between the

electrodes

3 and 4 is W, W is It can be expressed by the following formula (5).
W = (1/2) ・ ε ・ (2dx / d) ・ v ² = εxv ² (5)

When the energy applied per unit volume of the article to be heated 6 is E, E can be represented by the following equation (6) from the above equations (4) and (5).
E = W / V = ρg · εxv ² / 6dTcosθ (6)

On the other hand, when the partition member 7 is arranged between the electrode 3 and the electrode 4, the object to be heated 6 is surrounded by the electrode 3, the electrode 4, the front wall surface of the container 5 and the partition member 7 due to the capillary phenomenon. Supplied in a tube. The height h ′ of the liquid surface of the article 6 to be heated that rises in the tube can be expressed by the following equation (7).
h ′ = 4T cos θ / ρgd (7)

Since the cross-sectional area of the tube is d ² , the volume V ′ of the object to be heated 6 supplied into the tube by the capillary phenomenon can be expressed by the following formula (8).
V ′ = d ² · h ′ = 4d Tcos θ / ρg (8)

The energy E ′ added per unit volume of the object to be heated 6 existing in the tube is the energy W stored between the electrode 3 and the electrode 4, and the above equations (5) and (8) are used. ) And can be represented by the following formula (9).
E ′ = W / V ′ = ρg · εxv ² / 4dTcosθ (9)

As is clear from (6) and (9) above, the configuration in which the partition member 7 is arranged between the

electrodes

3 and 4 is different from the configuration in which the partition member 7 is not arranged between the

electrodes

3 and 4. In comparison, the energy applied per unit volume of the article to be heated 6 becomes large. As a result, the heating time required for the heated object 6 to vaporize can be shortened.

It is assumed that the dielectric loss of the partition member 7 is sufficiently smaller than the dielectric loss of the object 6 to be heated and can be ignored, but the dielectric loss of the partition member 7 cannot be ignored with respect to the dielectric loss of the object 6 to be heated. When the size is large, the heating effect of the object 6 to be heated is reduced. Therefore, the partition member 7 needs to be made of a material having a relative dielectric constant smaller than that of the object 6 to be heated.

5 and 6 show a configuration in which only one partition member 7 is arranged between the

electrodes

3 and 4, but a plurality of partition members 7 are arranged between the

electrodes

3 and 4. May be.
Further, the partition member 7 may be provided between the electrode 3A and the electrode 4A included in the dielectric heating device 1A shown in FIG. For example, the partition member 7 is arranged between the wall surface 5A-1 and the wall surface 5A-2 of the container 5A. By providing the partition member 7, the energy applied per unit volume of the object to be heated 6 becomes large, so that the heating time required for the object to be heated 6 to vaporize can be shortened.

Further, in order to prevent deterioration of the surfaces of the electrodes 3 and 4 (for example, rust) or deterioration of heating performance due to contact with the object to be heated 6, deterioration of the electrode surfaces of the

electrodes

3 and 4 is prevented. May be coated. Further, a partition member different from the partition member 7 may be provided between the

electrodes

3 and 4 and the object 6 to be heated so that the object 6 to be heated does not come into contact with the

electrodes

3 and 4. As the partition member, for example, a glass member can be used.

As described above, the dielectric heating device 1B according to the second embodiment includes the partition member 7 having a smaller dielectric loss than the object 6 to be heated between the electrode 3 and the electrode 4, so that the electrode 3 and the electrode 4 are separated from each other. The volume occupied by the article 6 to be heated can be reduced. As a result, the energy applied per unit volume of the article to be heated 6 when an electric field is generated between the

electrodes

3 and 4 is increased, so that the heating time required for the article to be heated 6 to vaporize is shortened. can do.

Embodiment 3.
FIG. 7 is a perspective view showing a configuration example of the dielectric heating device 1C according to the third embodiment. 7, the same components as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. The dielectric heating device 1C includes a signal source 2, an electrode 3, an electrode 4, a container 5 and an electrode 8.

The electrode 8 is a third electrode which is arranged to face the electrode 3 and is grounded. The electrode 8 is a conductor that is connected to the ground terminal b of the signal source 2 and that generates an electric field between the electrode 8 and the electrode 3 to which a high-frequency signal is applied from the signal source 2. The electrode 8 is connected to the container 5 and its position is fixed. A metal flat plate may be used for the electrode 8, for example.

The material forming the electrode 8 may be any material that can generate a high-frequency electric field with the electrode 3, and a plurality of materials may be used for the electrode 8. In FIG. 7, each of the

electrodes

3 and 4 and the

electrodes

3 and 8 functions as a capacitor, and a space between the

electrodes

3 and 4 and between the

electrodes

3 and 8 is heated by a capillary phenomenon. The item 6 is supplied.

Further, the height of the liquid surface of the object to be heated 6 supplied between the

electrodes

3 and 4 and the height of the liquid surface of the object to be heated 6 supplied between the

electrodes

3 and 8 are , Higher than the liquid surface of the object 6 to be heated held in the container 5. That is, in the dielectric heating device 1C, the object 6 to be heated is supplied by the capillary phenomenon into the first tube surrounded by the wall surfaces of the electrode 3, the electrode 4 and the container 5, and thus the electrode 3, the electrode 8 and the container 5 are surrounded. The object 6 to be heated is supplied by the capillary phenomenon into the second tube surrounded by the wall surface.

For example, the cross-sectional area of the first tube to which the object to be heated 6 is supplied by the capillarity is 1/10 or less of the area S _B of the liquid surface of the object to be heated 6 in the container 5, The cross-sectional area of the second pipe to which the heating object 6 is supplied is not more than 1/10 of the area S _B of the liquid surface of the heating object 6.

The

electrodes

3, 4 and 8 are metal parallel plates, the container 5 is a rectangular parallelepiped glass container, and the heated object 6 and air are present inside the container 5. When the high frequency signal generated by the signal source 2 is applied to the electrode 3 via the output terminal a, a high frequency electric field is generated between the electrode 3 and the electrode 4, between the electrode 3 and the electrode 8 and in the vicinity thereof. To do. Since a high frequency signal is applied to the electrode 3 and the

electrodes

4 and 8 are grounded, an electric field from the electrode 3 toward the

electrodes

4 and 8 is generated.

FIG. 8 is a top view showing lines of electric force formed by the electric field generated between the

electrodes

3 and 4 arranged in parallel. The dashed arrow is the line of electric force. In the dielectric heating device according to the first and second embodiments, as shown in FIG. 8, the electrode 3 and the electrode 4 are arranged in parallel. Therefore, when a high frequency signal is applied to the electrode 3, the lines of electric force are generated from the electrode 3 toward the electrode 4. At this time, the lines of electric force are mainly generated between the

electrodes

3 and 4, but some of the lines of electric force are widely generated at both ends of the

electrodes

3 and 4, as shown in FIG. .

The density of electric lines of force indicates the strength of the electric field. In FIG. 8, the electric field is strongly generated between the electrode 3 and the electrode 4, but it is also generated from both ends of the electrode 3 and the electrode 4 with a non-negligible strength. Since the object 6 to be heated is supplied between the

electrodes

3 and 4, the electric field generated between the

electrodes

3 and 4 is used to heat the object 6 to be heated. The electric field generated except between and is not used for heating.

FIG. 9 is a top view showing electric lines of force formed by electric fields generated between the

electrodes

3 and 4 and between the

electrodes

3 and 8 which are arranged in parallel. The dashed arrow is the line of electric force. In the dielectric heating device 1C, as shown in FIG. 9, the electrode 3 is arranged in parallel between the electrode 4 and the electrode 8. When a high-frequency signal is applied to the electrode 3, the lines of electric force are mainly generated from the electrode 3 to the electrode 4 and from the electrode 3 to the electrode 8. Some of the lines of electric force are generated at both ends of the

electrodes

3 and 4, and are generated at both ends of the

electrodes

3 and 8.

However, comparing FIG. 8 and FIG. 9, the lines of electric force generated at both ends of the

electrodes

3 and 4 and both ends of the

electrodes

3 and 8 shown in FIG. It is less dense than the lines of electric force generated at the ends of the electrodes 4. That is, in the dielectric heating device 1C, the electric field generated except between the electrodes is weak. Therefore, leakage of the electric field to the outside of the dielectric heating device 1C is reduced. Further, in the dielectric heating device 1C, most of the generated electric field is used for heating the object 6 to be heated, so that the heating time required for the object 6 to be vaporized to be vaporized can be shortened.

7 and 9 show a configuration in which three electrodes are arranged in parallel, but in the dielectric heating device 1C according to the third embodiment, a high frequency signal is applied between two grounded electrodes. A configuration in which five or more odd-numbered electrodes are arranged may be arranged so that the electrodes are arranged. For example, it is provided with five flat plate-shaped electrodes (1) to (5), and the grounded electrode (1), the electrode (2) to which a high frequency signal is applied, the grounded electrode (3) and the high frequency signal are applied. The electrode (4) and the grounded electrode (5) are arranged in this order. Even with this configuration, leakage of the electric field to the outside of the dielectric heating device 1C is reduced. Furthermore, since most of the electric field generated between the electrodes can be used for heating the object 6 to be heated, the heating time required for the object 6 to be heated to vaporize can be shortened.

The partition member 7 shown in the second embodiment may be arranged between the

electrodes

3 and 4 and between the

electrodes

3 and 8. Further, in a configuration in which an odd number of five or more electrodes are arranged so that an electrode to which a high-frequency signal is applied is arranged between two grounded electrodes, a partition member 7 is arranged between the electrodes. Good. By arranging the partition member 7 between the electrodes, the effect shown in the second embodiment can be obtained.

FIG. 10 is a top view showing lines of electric force formed by an electric field generated between the

electrodes

3B and 4B arranged concentrically. In FIG. 10, the dashed arrow is the line of electric force. The cylindrical electrode 4B is arranged around the columnar electrode 3B. When a high frequency signal is applied to the electrode 3B, an electric force line is generated from the electrode 3B toward the inner wall of the electrode 4B, and no electric force line is generated except between the electrode 3B and the electrode 4B. Therefore, leakage of the electric field to the outside of the dielectric heating device is reduced.

Further, the dielectric heating device having the electrode structure shown in FIG. 10 can utilize more of the electric field generated between the electrodes for heating the object to be heated 6 than the electrode structure shown in FIG. As a result, the heating time required for the heated object 6 to vaporize can be shortened.
Although the columnar electrode 3B and the cylindrical electrode 4B are shown in FIG. 10, the electrode 3B may be columnar and the electrode 4B may be cylindrical. For example, the electrode 3B may have a polygonal columnar shape, and the electrode 4B may have a polygonal cylindrical shape.

Although FIG. 10 shows a configuration in which two electrodes are concentrically arranged, the dielectric heating device 1C may have a configuration in which an even number of four or more electrodes are concentrically arranged. For example, a cylindrical electrode (2a) having a columnar electrode (1a) and cylindrical electrodes (2a) to (4a), which is grounded around the columnar electrode (1a) to which a high frequency signal is applied. The cylindrical electrode (3a) to which a high frequency signal is applied and the grounded cylindrical electrode (4a) are concentrically arranged in this order. Even with this configuration, leakage of the electric field to the outside of the dielectric heating device 1C is reduced. Furthermore, since most of the electric field generated between the electrodes can be used for heating the object 6 to be heated, the heating time required for the object 6 to be heated to vaporize can be shortened.

The partition member 7 shown in the second embodiment may be arranged between the electrode 3B and the electrode 4B shown in FIG. Furthermore, in a configuration in which four or more even-numbered electrodes are arranged concentrically, the partition member 7 may be arranged between each electrode. By arranging the partition member 7 between the electrodes, the effect shown in the second embodiment can be obtained.

In order to prevent deterioration (for example, rust) of the surface of the electrode 3, the electrode 4 and the electrode 8 or the electrode 3B and the electrode 4B or deterioration of the heating performance due to contact with the object 6 to be heated, deterioration prevention The coating may be applied to the electrode surface. Further, a partition member other than the partition member 7 may be provided between each electrode and the object to be heated 6 so that the object to be heated 6 does not come into contact with the electrodes. As the partition member, for example, a glass member can be used.

As described above, the dielectric heating device 1C according to the third embodiment includes, in addition to the electrode 3 and the electrode 4, the electrode 8 that is arranged to face the electrode 3 and is grounded. An object to be heated 6 is supplied between the

electrodes

3 and 8 by a capillary phenomenon, and an electric field generated between the electrode 3 to which a high frequency signal is applied from the signal source 2 and the grounded electrode 8 is generated. The object 6 to be heated supplied between the electrode 3 and the electrode 8 is heated. With this configuration, leakage of the electric field to the outside of the dielectric heating device 1C is reduced. Further, most of the electric field generated between the electrodes can be used for heating the object 6 to be heated, so that the heating time required for the object 6 to be vaporized to be vaporized can be shortened.

Fourth Embodiment
In the fourth embodiment, a dielectric heating device in which the distance between two electrodes is different in the height direction will be described. FIG. 11 is a perspective view showing a configuration example of the dielectric heating device 1D according to the fourth embodiment. 11, the same components as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. The dielectric heating device 1D includes a signal source 2, a container 5, an electrode 9 and an electrode 10.

The electrode 9 is a first electrode connected to the output terminal a of the signal source 2, and is a conductor that generates an electric field with the electrode 10. The electrode 9 is connected to the container 5 and its position is fixed. When the high frequency signal generated by the signal source 2 is applied to the electrode 9 via the output terminal a, a high frequency electric field is generated between the electrode 9 and the electrode 10. A metal flat plate may be used for the electrode 9, for example. The material forming the electrode 9 may be any material that can generate a high-frequency electric field with the electrode 10, and a plurality of materials may be used for the electrode 9.

The electrode 10 is a second electrode which is arranged facing the electrode 9 and is grounded. The electrode 10 is a conductor that is connected to the ground terminal b of the signal source 2 and that generates an electric field between the electrode 10 and the electrode 9 to which a high-frequency signal is applied from the signal source 2. The electrode 10 is connected to the container 5 and its position is fixed. For the electrode 10, for example, a metal flat plate may be used. The material forming the electrode 10 may be any material that can generate a high-frequency electric field with the electrode 9, and a plurality of materials may be used for the electrode 10.

As shown in FIG. 11, the

electrodes

9 and 10 have a shape in which the thickness gradually increases along the direction (height direction) away from the bottom surface side of the container 5. When the

electrodes

9 and 10 are arranged so as to face each other, the distance between the

electrodes

9 and 10 becomes narrower along the height direction of the

electrodes

9 and 10. That is, the interval between the electrode 9 and the electrode 10 is partially narrowed.

FIG. 12 is a front view showing a configuration example of the dielectric heating device 1D according to the fourth embodiment. In FIG. 12, the front surface of the container 5 is transparent so that the inside of the container 5 can be visually recognized. The

electrodes

9 and 10 are metal members, and the container 5 is a rectangular parallelepiped glass container. The object to be heated 6 held in the container 5 moves in the direction indicated by the solid arrow by the capillary phenomenon and is supplied between the electrode 9 and the electrode 10. The dashed arrow indicates the line of electric force formed by the electric field generated between the electrode 9 and the electrode 10 by applying a high frequency signal.

In FIG. 12, the direction toward the bottom side of the container 5 is the downward direction, and the direction away from the bottom side of the container 5 is the upward direction. In the dielectric heating device 1D, the density of the lines of electric force generated in the upper portion where the distance between the

electrodes

9 and 10 is narrow is high. That is, since the strength of the electric field generated in the upper portion where the distance between the electrode 9 and the electrode 10 is narrow increases, the heated object 6 heated in this portion vaporizes.

-The capacitance of a capacitor composed of two plates is proportional to the area of the plates and inversely proportional to the distance between the plates. That is, the smaller the distance between the flat plates, the larger the electrostatic capacity and the stronger the electric field. As shown in FIG. 11, in the dielectric heating device 1D, the electric field strength increases in the upper portion where the distance between the electrode 9 and the electrode 10 is narrow, and the object 6 to be heated is intensively heated in this portion. As a result, the heating time required for the heated object 6 to vaporize can be shortened.

Further, the dielectric heating device 1D may have a configuration in which the interval between the electrodes shown in FIG. 4, FIG. 7 or FIG. 10 is partially narrowed. Further, in an arrangement in which an odd number of electrodes of 5 or more is arranged so that an electrode to which a high frequency signal is applied is arranged between two electrodes which are grounded, the interval between the electrodes is partially narrowed. Good. Further, in the dielectric heating device 1D, in a configuration in which four or more even-numbered electrodes are arranged concentrically, the interval between the electrodes may be partially narrowed.
Even with these configurations, the object to be heated 6 supplied to the portion where the interval between the electrodes is narrow is intensively heated by the capillary phenomenon, so that the heating time required for the object to be heated 6 to be vaporized is shortened. be able to. Further, in these configurations, the partition member 7 shown in the second embodiment is arranged between the electrodes, so that the effect shown in the second embodiment can be obtained.

Incidentally, in order to prevent the deterioration of the surfaces of the

electrodes

9 and 10 or the deterioration of the heating performance due to the contact with the object 6 to be heated, a deterioration preventing coating may be applied to the electrode surfaces. Further, a partition member other than the partition member 7 may be provided between each electrode and the object to be heated 6 so that the object to be heated 6 does not come into contact with the electrodes. As the partition member, for example, a glass member can be used.

As described above, in the dielectric heating device 1D according to the fourth embodiment, the gap between the electrode 9 and the electrode 10 is partially narrowed. With such a configuration, the object 6 to be heated is intensively heated at a place where the interval between the electrodes is narrow, and thus the heating time required for the object 6 to be heated to be vaporized can be shortened.

In addition, in the dielectric heating device 1D according to the fourth embodiment, it suffices that the gap between the electrodes is partially narrowed, and the portion that narrows the gap is not limited to the upper portion.
For example, the interval between the electrodes may be narrowed in the lower part, or may be narrowed in the middle part between the lower side and the upper side. In any of the configurations, the object 6 to be heated is intensively heated in the portion where the distance between the electrodes is narrow, so that the heating time required until the object 6 to be heated is vaporized can be shortened.

It should be noted that the present invention is not limited to the above-described embodiments, and within the scope of the present invention, each free combination of the embodiments or any modification of any of the constituent elements of the embodiments or the embodiments. It is possible to omit arbitrary components in each of the above.

Since the dielectric heating device according to the present invention can shorten the heating time until the object to be heated is vaporized, it can be used for various devices that heat a liquid object to be heated to generate an aerosol.

1, 1A, 1B, 1C, 1D dielectric heating device, 2 signal sources, 3, 3A, 3B, 4, 4A, 4B, 8, 9, 10 electrodes, 5, 5A container, 5A-1, 5A-2 wall surface, 6 objects to be heated, 7 partition members.

Claims

A signal source for generating a high frequency signal,
A first electrode connected to the signal source,
A second electrode which is arranged to face the first electrode and is grounded;
Equipped with
An object to be heated is supplied between the first electrode and the second electrode by a capillary phenomenon,
An electric field generated between the first electrode to which a high-frequency signal is applied from the signal source and the grounded second electrode causes a gap between the first electrode and the second electrode. A dielectric heating device, which heats the supplied object to be heated.
A container for holding the object to be heated,
The liquid level of the object to be heated supplied between the first electrode and the second electrode is higher than the liquid level of the object to be heated held in the container. 1. The dielectric heating device according to 1.
The dielectric heating device according to claim 1, further comprising a partition member that is disposed between the first electrode and the second electrode and has a dielectric loss smaller than that of the object to be heated.
The first electrode is a columnar electrode,
The second electrode is a tubular electrode,
The said 1st electrode and the said 2nd electrode are arrange | positioned concentrically centering | focusing on the said 1st electrode, The dielectric heating apparatus of any one of Claim 1 to 3 characterized by the above-mentioned.
A third electrode which is arranged to face the first electrode and is grounded,
The object to be heated is supplied between the first electrode and the third electrode by a capillary phenomenon,
An electric field generated between the first electrode to which a high-frequency signal is applied from the signal source and the grounded third electrode causes a gap between the first electrode and the third electrode. The dielectric heating device according to claim 1, wherein the supplied object to be heated is heated.
A container for holding the object to be heated,
The liquid surface of the object to be heated supplied between the first electrode and the second electrode, and the object to be heated supplied between the first electrode and the third electrode The liquid level is higher than the liquid level of the object to be heated held in the container.
A partition member that is arranged between the first electrode and the second electrode and has a dielectric loss smaller than that of the object to be heated, and is arranged between the first electrode and the third electrode. And a partition member having a dielectric loss smaller than that of the object to be heated. 7. The dielectric heating device according to claim 5, further comprising:
The dielectric heating device according to claim 1, wherein a gap between the first electrode and the second electrode is partially narrowed.
The interval between the first electrode and the second electrode is partially narrowed,
The dielectric heating device according to claim 5, wherein a distance between the first electrode and the third electrode is partially narrowed.
A cross-sectional area of a portion where a capillary phenomenon occurs between the first electrode and the second electrode is 1/10 or less of an area of a liquid surface of the object to be heated in the container. The dielectric heating device according to claim 2.
The cross-sectional area of the portion where the capillary phenomenon occurs between the first electrode and the second electrode is 1/10 or less of the area of the liquid surface of the object to be heated in the container,
The cross-sectional area of the portion where the capillary phenomenon occurs between the first electrode and the third electrode is 1/10 or less of the area of the liquid surface of the object to be heated in the container. The dielectric heating device according to claim 6.