Electromagnetic wave heating device

Abstract

In an electromagnetic wave heating device that can be used to heat an object laminated on a substrate, the heating efficiency of the object to be heated is ensured while suppressing friction of the substrate with the circuit that forms the electric field. [Solution] The electromagnetic wave heating device 10 includes a first field forming circuit 20 having a plurality of first conductor lines 31a arranged with gaps in a first direction, a second field forming circuit 25 having a plurality of second conductor lines 32a arranged with gaps in a second direction, wherein the arrangement region of the second conductor lines 32a faces the arrangement region of the first conductor lines 31a via a gap G1, and an input unit 15 that inputs electromagnetic waves transmitted through an unbalanced line to the field forming unit 12. During the input period when electromagnetic waves are input to the input unit 15, standing waves due to the resonance of electromagnetic waves are generated at multiple locations in the field forming unit 12, and a strong electric field region for heating the object to be heated is formed in the inter-circuit region 30 sandwiched between the first field forming circuit 20 and the second field forming circuit 25.

Description

[Technical Field]

[0001] The present invention relates to an electromagnetic wave heating device used for heating objects to be heated. [Background technology]

[0002] Conventionally, dielectric heating electromagnetic wave heating devices have been used for various applications, such as heating food. Electromagnetic wave heating devices irradiate the dielectric material contained in the object to be heated with electromagnetic waves. As a result, the electric field created by the electromagnetic waves causes molecular-level dipoles in the dielectric to vibrate, and the dielectric loss associated with this vibration generates heat, thus heating the object to be heated. In addition, with high-frequency heating methods other than dielectric heating, if the object to be heated contains conductive components or ionic substances, the heating occurs due to conductivity (Joule) loss caused by the electric current, and if it contains magnetic components, the heating occurs due to magnetic loss.

[0003] Patent Document 1 describes a drying apparatus in which a positive electrode and a negative electrode are arranged in parallel as electrodes for high-frequency application. Figure 10 of Patent Document 1 shows a transport path between the negative electrode and the positive electrode as a transport path through which the medium to which the ink is applied passes. A balanced circuit is used in the drying apparatus described in Patent Document 1.

[0004] Patent Document 2 describes an electromagnetic wave heating device using an unbalanced circuit. This electromagnetic wave heating device heats an object to be heated on a sheet-like, long substrate. This electromagnetic wave heating device is provided with a first comb-shaped electrode and a second comb-shaped electrode that interlock with a gap between them in the same plane. High frequency is supplied to the first comb-shaped electrode from a coaxial connector (input section) to which a coaxial cable (unbalanced line) is connected. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2019-162771 [Patent Document 2] Japanese Patent Publication No. 2022-25839 [Overview of the project] [Problems that the invention aims to solve]

[0006] Incidentally, in the electromagnetic wave heating device described in Patent Document 2, a thin, strong electric field region is formed near the first and second comb-shaped electrodes, which are arranged in the same plane. Therefore, when heating an object to be heated that is laminated on a substrate, it is necessary to bring the substrate close to the first and second comb-shaped electrodes in order to increase the heating efficiency of the object to be heated. However, in this case, there is a risk that the substrate may be scratched by rubbing against the first and second comb-shaped electrodes.

[0007] This invention has been made in view of these circumstances, and aims to provide an electromagnetic wave heating device that can be used to heat an object laminated on a substrate, while ensuring the heating efficiency of the object to be heated and suppressing friction of the substrate with the circuit that forms the electric field. [Means for solving the problem]

[0008] To solve the above-mentioned problems, the first invention is an electromagnetic wave heating device that heats an object to be heated using electromagnetic waves, comprising: a first field forming circuit having a plurality of first conductor lines arranged with gaps in a first direction; a second field forming circuit having a plurality of second conductor lines arranged with gaps in a second direction, wherein the arrangement region of the second conductor lines faces the arrangement region of the first conductor lines through a gap; and an input unit that inputs electromagnetic waves transmitted through an unbalanced line into the field forming unit including the first field forming circuit and the second field forming circuit, wherein during the input period when electromagnetic waves are input into the input unit, standing waves due to the resonance of electromagnetic waves are generated at multiple locations in the field forming unit, and a strong electric field region for heating the object to be heated is formed in the inter-circuit region sandwiched between the first field forming circuit and the second field forming circuit.

[0009] The second invention is the first invention, further comprising a first grounding electrode in contact with the first field forming circuit, wherein the first grounding electrode is formed as an electromagnetic wave shielding structure to shield the side of the first field forming circuit opposite to the inter-circuit region.

[0010] The third invention is the same as the second invention, wherein the array region of the first conductor lines and the array region of the second conductor lines are parallel to each other, the first ground electrode faces the plurality of first conductor lines on the opposite side from the inter-circuit region, and has a facing shielding portion that forms a shielding space between itself and the plurality of first conductor lines, and in a direction perpendicular to the array region of the first conductor lines, the distance between the first conductor line and the facing shielding portion is three times or more the distance between the first conductor line and the second conductor line.

[0011] The fourth invention is the first invention, wherein the input unit inputs electromagnetic waves transmitted through an unbalanced line to a first field forming circuit, the first field forming circuit has a base line to which one end of each of a plurality of first conductor lines is connected, and has a linear contact portion provided along the base line and in contact with the base line, and further includes a heat dissipation member that dissipates heat from the base line through the linear contact portion.

[0012] The fifth invention is the fourth invention, wherein the first electric field forming circuit has a circuit-side frame-shaped portion that includes a base line in part and surrounds the plurality of first conductor lines spaced apart from the other end of each of the plurality of first conductor lines, and the heat dissipation member has a heat dissipation-side frame-shaped portion that includes a linear contact portion and contacts the circuit-side frame-shaped portion around its entire circumference.

[0013] The sixth invention is the first invention, wherein the first ground electrode in contact with the first electric field forming circuit, It further comprises a second ground electrode that contacts the second electric field forming circuit.

[0014] The seventh invention is the first invention further comprising an oscillator that outputs electromagnetic waves toward the input section, where the wavelength of the electromagnetic waves in the oscillator is λ and the length of the first conductor line is L1, in which case Equation 1 holds true. α×λ×(2n-1) / 4≦L1≦λ×(2n-1) / 4 (Formula 1) Here, α is 0.6 and n represents a natural number.

[0015] The eighth invention, according to the first invention, further comprises an oscillator that outputs electromagnetic waves toward an input unit, wherein the electromagnetic wave density obtained by dividing the output power of the oscillator by the area of the inter-circuit region in a plan view is 25 W / cm 2 or less.

[0016] The ninth invention, according to the first invention, wherein of the first electric field forming circuit and the second electric field forming circuit, the one disposed on an upper side is defined as an upper electric field forming circuit, and the one disposed on a lower side is defined as a lower electric field forming circuit, further comprising: an upper compartment formed in a box shape with an opening provided on the lower side, disposed such that the opening is closed by the upper electric field forming circuit, and having an upper introduction port and an upper discharge port as an air passage; and an upper exhaust fan that exhausts air from the inside of the upper compartment through the upper discharge port.

[0017] The tenth invention, according to the ninth invention, further comprises an upper air supply fan that supplies air into the upper compartment through the upper introduction port.

[0018] The eleventh invention, according to the ninth invention, further comprises: a lower compartment formed in a box shape with an opening provided on the upper side, disposed such that the opening is closed by the lower electric field forming circuit, and having a lower introduction port and a lower discharge port as an air passage; and a lower exhaust fan that exhausts air from the inside of the lower compartment through the lower discharge port.

[0019] The twelfth invention, according to the first invention, wherein the first conductor line and / or the second conductor line is provided with a width changing portion whose width changes locally in plan view, or a bent portion bent so as to protrude laterally.

[0020] The thirteenth invention, according to the first invention, wherein the second direction is the same direction as the first direction.

[0021] The fourteenth invention, according to the first invention, further comprises a frame-shaped shield portion provided around the electric field forming unit for blocking leakage of electromagnetic waves from the gap in the inter-circuit region, wherein a choke structure is provided in the frame-shaped shield portion.

[0022] The 15th invention further comprises, in the first invention, an oscillator that outputs electromagnetic waves toward an input section, and a control unit that controls the oscillation frequency of the oscillator so that the oscillation frequency of the oscillator follows the resonant frequency of the electromagnetic waves in the field forming section, based on (i) the intensity of the reflected electromagnetic waves returning from the input section to the oscillator, or (ii) the difference between the phase of the incident electromagnetic waves going from the oscillator toward the input section and the phase of the reflected electromagnetic waves returning from the input section to the oscillator. [Effects of the Invention]

[0023] In this invention, during the input period when electromagnetic waves are input to the input section, a strong electric field region is formed in the inter-circuit region sandwiched between the first electric field forming circuit and the second electric field forming circuit. During the input period, standing waves due to electromagnetic wave resonance are simultaneously generated at multiple locations in the electric field forming section, and furthermore, since the array region of the first conductor line and the array region of the second conductor line face each other with a gap in between, electromagnetic waves propagate between the first conductor line and the second conductor line. As a result, the electric field in the middle of the gap becomes relatively strong in the inter-circuit region. When heating an object to be heated laminated on a substrate, heating efficiency is ensured even if the substrate passes through the middle of the gap. In other words, heating efficiency is ensured even if the substrate is spaced apart from each electric field forming circuit. According to this invention, in an electromagnetic wave heating device that can be used to heat an object to be heated laminated on a substrate, it is possible to suppress friction of the substrate against the electric field forming circuit while ensuring the heating efficiency of the object to be heated. [Brief explanation of the drawing]

[0024] [Figure 1] Figure 1(A) is a perspective view of an electromagnetic wave heating device according to an embodiment, with the ventilation device omitted, and Figure 1(B) is a side view of the electromagnetic wave heating device shown in Figure 1(A). [Figure 2] Figure 2(A) is a cross-sectional view of the electromagnetic heating device at cutting position AA in Figure 1(A), and Figure 2(B) is a cross-sectional view of the electromagnetic heating device at cutting position BB in Figure 1(A). [Figure 3] Figure 3 is an exploded perspective view of the electromagnetic wave heating device shown in Figure 1(A). [Figure 4]Figure 4 is an exploded perspective view of the electric field forming section of the electromagnetic wave heating device shown in Figure 1(A). [Figure 5] Figure 5(A) is a plan view showing how the substrate passes above the first field forming circuit in the electromagnetic wave heating device of Figure 1(A), and Figure 5(B) is a plan view showing how the substrate passes above the first field forming circuit in the electromagnetic wave heating device according to the first modified embodiment. [Figure 6] Figure 6(A) is a plan view of the first field formation circuit of an electromagnetic wave heating device according to a second modified embodiment; Figure 6(B) is a plan view of the second field formation circuit of the electromagnetic wave heating device according to the second modified embodiment; and Figure 6(C) is a plan view of a first field formation circuit in a different form from that of Figure 6(A). [Figure 7] Figure 7 is a schematic diagram of an electromagnetic wave heating device according to a third modified embodiment. [Figure 8] Figure 8 is a cross-sectional view of an electromagnetic wave heating device according to a fourth modified example of the embodiment. [Figure 9] Figure 9 is a cross-sectional view of an electromagnetic wave heating device according to another embodiment. [Modes for carrying out the invention]

[0025] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. Note that the following embodiments and modifications are examples of the present invention and are not intended to limit the scope of the present invention, its applications, or its uses.

[0026] This embodiment is an electromagnetic wave heating device 10 that heats an object to be heated 2 using electromagnetic waves (high frequency). The electromagnetic wave heating device 10 is a dielectric heating type heating device.

[0027] The object to be heated 2, which is heated by the electromagnetic wave heating device 10, contains a substance (liquid, solid, etc.) that absorbs electromagnetic waves and is in the form of a sheet. The object to be heated 2 is, for example, ink or adhesive. The object to be heated 2 is, for example, applied to or placed on the surface of a long, sheet-like substrate 1 and transported together with the substrate 1 in a predetermined direction, passing through a strong electric field region described later. At that time, the object to be heated 2 is heated by absorbing electromagnetic waves. The object to be heated 2 does not have to be in the form of a sheet and may have a certain thickness. Hereinafter, the transport direction of the substrate 1 and the object to be heated 2 will simply be referred to as the "transport direction". In the electromagnetic wave heating device 10, the side of the substrate 1 on which the object to be heated 2 is placed will be called the "front side", and the opposite side will be called the "back side" (see Figure 2).

[0028] [Configuration of an electromagnetic heating device] As shown in Figures 1-3, the electromagnetic wave heating device 10 includes an oscillator 11 that outputs electromagnetic waves (high frequency), an electric field forming unit 12 to which the electromagnetic waves output from the oscillator 11 are supplied, a frame-shaped shielding unit 13 to prevent leakage of electromagnetic waves from the electric field forming unit 12, and a ventilation device 14 for discharging water vapor generated as the object to be heated 2 is heated.

[0029] Here, the electromagnetic wave heating device 10, together with the transport mechanism 5 (see Figure 2(A)) that transports the base material 1, constitutes a transport-type processing system. The transport mechanism 5 transports the base material 1 and the object to be heated 2 using multiple pairs of rollers 3.

[0030] As shown in Figures 2(A) and 4, the electric field forming unit 12 includes a first electric field forming circuit 20 having a plurality of first conductor lines 31a arranged with gaps in a first direction, a second electric field forming circuit 25 having a plurality of second conductor lines 32a arranged with gaps in a second direction, and an input unit 15 that inputs electromagnetic waves transmitted through the unbalanced line to at least one of the first electric field forming circuit 20 and the second electric field forming circuit 25. Each first conductor line 31a and each second conductor line 32a is a straight rod shape with a substantially rectangular cross-sectional shape. In this embodiment, the first direction is the same as the second direction. The first and second directions are the same directions as the transport direction of the substrate 1. In the electric field forming unit 12, the arrangement region of the second conductor lines 32a faces the arrangement region of the first conductor lines 31a via a gap G1. The arrangement region of the first conductor line 31a and the arrangement region of the second conductor line 32a are parallel to each other.

[0031] The "arrangement region of the first conductor line 31a" is a flat plate-shaped region formed by the first conductor line 31a and the gaps between the first conductor lines 31a. The "arrangement region of the second conductor line 32a" is a flat plate-shaped region formed by the second conductor line 32a and the gaps between the second conductor lines 32a.

[0032] In this embodiment, each electric field forming circuit 20, 25 has a number of conductor lines 31a, 32a. Here, "a number" means 5 or more. However, the number of conductor lines 31a, 32a only needs to be 2 or more.

[0033] The input section 15 is composed of an unbalanced transmission line. The input section 15 is, for example, an input terminal for a coaxial cable. The input section 15 has a signal line 15a through which electromagnetic waves flow and a ground conductor 15b having ground potential. As shown in Figure 2(A), the signal line 15a is connected to the first field forming circuit 20. The ground conductor 15b is connected to the first ground electrode 40, which will be described later. In this embodiment, the input section 15 causes the electromagnetic waves transmitted through the unbalanced transmission line to be input to the first field forming circuit 20. The first field forming circuit 20 functions as an unbalanced circuit with the first ground electrode 40 as ground. The electromagnetic waves input to the first field forming circuit 20 propagate to the second field forming circuit 25 through the gap G1. The second field forming circuit 25 also functions as an unbalanced circuit with the second ground electrode 45, which will be described later, as ground.

[0034] In this embodiment, the signal line 15a is connected to the first conductor line 31a on the upstream side in the carrier direction of the first field formation circuit 20. The oscillator 11 is directly connected to the input unit 15. However, the oscillator 11 may also be connected to the input unit 15 via an unbalanced line such as a coaxial cable.

[0035] Each of the first field forming circuit 20 and the second field forming circuit 25 is made of a conductor (such as metal) and functions as an antenna that radiates electromagnetic waves. Each of the first field forming circuit 20 and the second field forming circuit 25 is formed in the shape of a flat plate of constant thickness, and comb-shaped gaps are provided to form comb-tooth electrodes 31 and 32 (see Figure 4), which will be described later. The first field forming circuit 20 is positioned on the lower side to form the lower field forming circuit, and the second field forming circuit 25 is positioned on the upper side to form the upper field forming circuit. In this embodiment, electromagnetic waves are directly supplied from the oscillator 11 to the first field forming circuit 20. Electromagnetic waves are not directly supplied from the oscillator 11 to the second field forming circuit 25.

[0036] During the input period when electromagnetic waves are input to the input unit 15, electromagnetic waves are supplied to the first field forming circuit 20. As a result, standing waves due to electromagnetic wave resonance are simultaneously generated at multiple locations in the field forming unit 12, and a strong electric field region for heating the object to be heated 2 is formed in the inter-circuit region 30 sandwiched between the first field forming circuit 20 and the second field forming circuit 25. The inter-circuit region 30 has a band shape when viewed from above. The object to be heated 2 passing through the strong electric field region is heated by high frequency, causing its dielectric and conductive components to be heated. As a result, the object to be heated 2 undergoes a temperature increase and a desired physical / chemical change (polymerization, annealing, drying, hardening, etc.) occurs.

[0037] As shown in Figure 4, the first electric field forming circuit 20 has a plurality of first conductor lines 31a, as well as a first circuit-side frame-shaped portion 21 to which one end (base) of each of the plurality of first conductor lines 31a is connected to the inner circumferential surface. The first circuit-side frame-shaped portion 21 surrounds the plurality of first conductor lines 31a, spaced apart from the other end (tip) of each of the plurality of first conductor lines 31a. The first circuit-side frame-shaped portion 21 is formed in a substantially rectangular frame shape. One side (long side) of the first circuit-side frame-shaped portion 21 constitutes a first base line 31b to which the bases of each of the plurality of first conductor lines 31a are connected. For example, the width of each of the first circuit-side frame-shaped portion 21 and the first base line 31b is greater than the width of the first conductor lines 31a. Each first conductor line 31a protrudes perpendicularly to the first base line 31b, but it may also protrude diagonally to the first base line 31b.

[0038] In the first electric field forming circuit 20, multiple first conductor lines 31a and a first base line 31b constitute the first comb-tooth electrode 31. Each first conductor line 31a constitutes a tooth of the first comb-tooth electrode 31. In the first comb-tooth electrode 31, multiple first conductor lines 31a are arranged parallel to each other in the same plane. The width and length of each first conductor line 31a are equal, and the multiple first conductor lines 31a are arranged at equal intervals. The spacing between adjacent first conductor lines 31a in the first direction is 10 times (or 6 times or less) the width of the first conductor line 31a. The dimension (height) of the gap G1 is smaller than the spacing between adjacent first conductor lines 31a in the first direction.

[0039] As shown in Figure 4, the second electric field forming circuit 25 has a plurality of second conductor lines 32a, as well as a second circuit-side frame-shaped portion 26 to which one end (base) of each of the plurality of second conductor lines 32a is connected to the inner circumferential surface. The second circuit-side frame-shaped portion 26 surrounds the plurality of second conductor lines 32a, spaced apart from the other end (tip) of each of the plurality of second conductor lines 32a. The second circuit-side frame-shaped portion 26 is formed in a substantially rectangular frame shape. One side (long side) of the second circuit-side frame-shaped portion 26 constitutes a second base line 32b to which the bases of each of the plurality of second conductor lines 32a are connected. For example, the width of each of the second circuit-side frame-shaped portion 26 and the second base line 32b is greater than the width of the second conductor lines 32a. Each second conductor line 32a protrudes perpendicularly to the second base line 32b, but it may also protrude diagonally to the second base line 32b.

[0040] In the second electric field forming circuit 25, multiple second conductor lines 32a and second base lines 32b constitute the second comb-shaped electrode 32. Each second conductor line 32a constitutes a tooth of the second comb-shaped electrode 32. In the second comb-shaped electrode 32, multiple second conductor lines 32a are arranged parallel to each other in the same plane. The width and length of each second conductor line 32a are equal, and the multiple second conductor lines 32a are arranged at equal angular intervals (for example, the same interval as the first conductor line 31a). The spacing between adjacent second conductor lines 32a in the second direction is 10 times or less (may be 6 times or less) the width of the second conductor line 32a. The dimension (height) of the gap G1 is smaller than the spacing between adjacent second conductor lines 32a in the second direction.

[0041] Regarding the positional relationship between the first electric field forming circuit 20 and the second electric field forming circuit 25, the first electric field forming circuit 20 and the second electric field forming circuit 25 face each other with a gap G1 through which the substrate 1 passes. The first circuit-side frame-shaped part 21 and the second circuit-side frame-shaped part 26 are the same shape and size. The first circuit-side frame-shaped part 21 and the second circuit-side frame-shaped part 26 are arranged parallel to each other and overlap perfectly in a plan view. In this embodiment, the first comb-tooth electrode 31 and the second comb-tooth electrode 32, which were conventionally arranged in the same plane, are arranged vertically so that a gap G1 is created between them. The object to be heated 2 is sandwiched between the first comb-tooth electrode 31 and the second comb-tooth electrode 32.

[0042] The first conductor line 31a and the second conductor line 32a protrude in opposite directions. Therefore, the tip of the first conductor line 31a is located near the base of the second conductor line 32a, and the tip of the second conductor line 32a is located near the base of the first conductor line 31a. In addition, the first comb-tooth electrode 31 and the second comb-tooth electrode 32 have multiple first conductor lines 31a and multiple second conductor lines 32a arranged in a staggered pattern. In other words, the positions of the multiple first conductor lines 31a and multiple second conductor lines 32a in the first direction are offset from each other by half a pitch. In a plan view, the first conductor line 31a is located at the center of the gap between adjacent second conductor lines 32a, and the second conductor line 32a is located at the center of the gap between adjacent first conductor lines 31a (see Figure 2(A)). The shortest distance between the first conductor line 31a and the second conductor line 32a (the shortest distance in the cross-sectional view in Figure 2(A)) is smaller than either the spacing of the first conductor line 31a or the spacing of the second conductor line 32a. In Figure 2(A), this shortest distance is the distance between the corners of the first conductor line 31a and the corners of the second conductor line 32a that are diagonally opposite to each other.

[0043] The electric field forming unit 12 further includes a first grounding electrode 40 that contacts the first electric field forming circuit 20 and a second grounding electrode 45 that contacts the second electric field forming circuit 25. Each grounding electrode 40 and 45 is grounded. Each grounding electrode 40 and 45 is formed as an electromagnetic wave shielding structure to shield the side opposite to the inter-circuit region 30 of the electric field forming circuits 20 and 25 that it contacts. The second grounding electrode 45 behaves as ground even when it is at a floating potential and no grounding conductor 15b or the like is connected, because its area is sufficiently large relative to the wavelength.

[0044] The first ground electrode 40 is a conductor formed to shield the side of the first electric field forming circuit 20 opposite to the inter-circuit region 30 (lower side) (see Figure 2(A)). The first ground electrode 40 is formed in the shape of a roughly rectangular box with an opening on the upper side. The first ground electrode 40 corresponds to the lower compartment portion, which is provided so that its opening is closed by the first electric field forming circuit (lower electric field forming circuit) 20.

[0045] The first ground electrode 40 is provided along the first base line 31b and has a first linear contact portion 41a that contacts (surface contact with) the first base line 31b (see Figures 2(B) and 4), and corresponds to a first heat dissipation member that dissipates heat from the first base line 31b through the first linear contact portion 41a.

[0046] The first ground electrode 40 has a first heat dissipation side frame-shaped portion 41 which includes a first linear contact portion 41a in part, and a first facing shield portion 42 which faces the plurality of first conductor lines 31a on the side opposite to the inter-circuit region 30. In the box-shaped first ground electrode 40, the first heat dissipation side frame-shaped portion 41 constitutes the side surface, and the first facing shield portion 42 constitutes the bottom surface. The lower end of the first heat dissipation side frame-shaped portion 41 is connected to the first facing shield portion 42.

[0047] The first heat dissipation side frame-shaped portion 41 is formed in a substantially rectangular frame shape. In a plan view, the first heat dissipation side frame-shaped portion 41 has the same shape and size as the first circuit side frame-shaped portion 21. In a plan view, the outer circumference of the first heat dissipation side frame-shaped portion 41 overlaps perfectly with the outer circumference of the first circuit side frame-shaped portion 21 and makes full contact (surface contact) with the first circuit side frame-shaped portion 21. The height of the first heat dissipation side frame-shaped portion 41 is greater than the height of the first circuit side frame-shaped portion 21.

[0048] The first opposing shielding portion 42 is formed in the shape of a substantially rectangular flat plate. The first opposing shielding portion 42 forms a first shielding space 71 between itself and the plurality of first conductor lines 31a (see Figure 2(A)). The first opposing shielding portion 42 is provided parallel to the arrangement region of the first conductor lines 31a. In a direction perpendicular to the arrangement region of the first conductor lines 31a, the distance D1 between the first conductor line 31a and the first opposing shielding portion 42 is equal to the distance D between the first conductor line 31a and the second conductor line 32a (height of the gap G1). G It is more than three times (see Figure 2(B)). The height of the gap G1 can be, for example, 1.5 mm or more and 3 mm or less. In this embodiment, distance D1 is distance D G It is set to be more than 5 times. In order to suppress the thickness of the electric field forming part 12, the distance D1 is set to distance D G It can be reduced to 20 times or less.

[0049] As shown in Figure 4, the first opposing shielding section 42 has a lower inlet 44 and a lower outlet 43 formed as air passages. Each of the lower inlet 44 and the lower outlet 43 is made up of multiple slit holes.

[0050] As shown in Figure 4, the first facing shielding section 42 has a through hole formed on the upstream side in the transport direction for passing the signal line 15a of the input section 15. The first heat dissipation side frame-shaped section 41 is provided with a conductor pin 16 for adjusting the impedance of the electric field forming section 12. The conductor pin 16 is fitted into the through hole of the first heat dissipation side frame-shaped section 41 and is movably provided relative to the first heat dissipation side frame-shaped section 41. By sliding the conductor pin 16, the length of its protrusion from the inner surface of the first heat dissipation side frame-shaped section 41 and the distance between the conductor pin 16 and the signal line 15a are changed, thereby adjusting the impedance of the electric field forming section 12. Since the conductor pin 16 is also inserted through the through hole 51a of the first shield section 51, the impedance can be adjusted from the outside of the frame-shaped shield section 13. In this specification, "distance between objects" means the shortest distance between two objects.

[0051] The second ground electrode 45 is a conductor formed to shield the side of the second field forming circuit 25 opposite to the inter-circuit region 30 (upper side) (see Figure 2(A)). The second ground electrode 45 is formed in the shape of a roughly rectangular box with an opening on the lower side. The second ground electrode 45 corresponds to the upper compartment portion, which is provided so that its opening is closed by the second field forming circuit (upper field forming circuit) 25.

[0052] The second ground electrode 45 has a second linear contact portion 46a that is provided along the second base line 32b and is in contact (surface contact) with the second base line 32b (see Figure 2(B)), and corresponds to a second heat dissipation member that dissipates heat from the second base line 32b through the second linear contact portion 46a.

[0053] The second ground electrode 45 has a second heat dissipation side frame-shaped portion 46 which includes a second linear contact portion 46a, and a second facing shield portion 47 which faces the plurality of second conductor lines 32a on the side opposite to the inter-circuit region 30. In the box-shaped second ground electrode 45, the second heat dissipation side frame-shaped portion 46 constitutes the side surface, and the second facing shield portion 47 constitutes the bottom surface. The upper end of the second heat dissipation side frame-shaped portion 46 is connected to the second facing shield portion 47.

[0054] The second heat dissipation side frame-shaped portion 46 is formed in a substantially rectangular frame shape. In a plan view, the second heat dissipation side frame-shaped portion 46 has the same shape and size as the second circuit side frame-shaped portion 26. In a plan view, the outer circumference of the second heat dissipation side frame-shaped portion 46 overlaps perfectly with the outer circumference of the second circuit side frame-shaped portion 26 and makes full contact (surface contact) with the second circuit side frame-shaped portion 26. The height of the second heat dissipation side frame-shaped portion 46 is greater than the height of the second circuit side frame-shaped portion 26.

[0055] The second opposing shielding portion 47 is formed in the shape of a substantially rectangular flat plate. The second opposing shielding portion 47 forms a second shielding space 72 between itself and the plurality of second conductor lines 32a (see Figure 2(A)). The second opposing shielding portion 47 is provided parallel to the arrangement region of the second conductor lines 32a. In a direction perpendicular to the arrangement region of the second conductor lines 32a, the distance D2 between the second conductor line 32a and the second opposing shielding portion 47 is equal to the distance D between the first conductor line 31a and the second conductor line 32a. G It is more than three times (see Figure 2(B)). In this embodiment, distance D2 is equal to distance D G It is set to more than 5 times. In order to suppress the thickness of the electric field forming part 12, the distance D2 is set to distance D G It can be reduced to 20 times or less.

[0056] As shown in Figure 4, the second opposing shielding section 47 has an upper inlet 49 and an upper outlet 48 formed as air passages. Each of the upper inlet 49 and the upper outlet 48 is made up of multiple slit holes.

[0057] The frame-shaped shielding section 13 is intended to prevent electromagnetic wave leakage from the gap G1 in the inter-circuit region 30. The frame-shaped shielding section 13 is provided around the electric field forming section 12 (see Figures 1 and 3). The frame-shaped shielding section 13 comprises a first shielding section 51 provided to surround the first electric field forming circuit 20 and the first ground electrode 40, and a second shielding section 52 provided to surround the second electric field forming circuit 25 and the second ground electrode 45. The first shielding section 51 is located below the second shielding section 52.

[0058] Between the first shield portion 51 and the second shield portion 52, a gap G2 is formed at least where the base material 1 passes, connecting to the gap G1 of the electric field forming portion 12 (see Figure 2). For example, the gap G2 is formed around the entire circumference of the frame-shaped shield portion 13. The second shield portion 52 is supported by a support member (not shown) so that it floats relative to the first shield portion 51. The height of the gap G2 can be, for example, 1.5 mm or more and 3 mm or less.

[0059] The first shield portion 51 is a frame-shaped member with a substantially rectangular opening formed on its inner side. The first ground electrode 40 is fitted into this opening. In cross-sectional view, the first shield portion 51, together with the sides of the first field forming circuit 20 and the first ground electrode 40, is bent to form a first choke structure 61 facing the gap G2. The first choke structure 61 is a choke groove that extends straight in the height direction.

[0060] The second shield portion 52 is a frame-shaped member with a substantially rectangular opening formed on its inner side. The second ground electrode 45 is fitted into this opening. In cross-sectional view, the second shield portion 52 has a protruding portion that extends downward, and together with the sides of the second field forming circuit 25 and the second ground electrode 45, it forms a second choke structure 62 facing the gap G2. The second choke structure 62 is a choke groove that extends straight in the height direction. In cross-sectional view, the second shield portion 52 has a third choke structure 63 on the outside of the protruding portion that faces the gap G2. The third choke structure 63 has a spiral-shaped space.

[0061] The frame-shaped shield section 13 employs choke structures 61-63, which cannot be used in balanced circuits. Each choke structure 61-63 is formed around the entire circumference of the electric field forming section 12. In each choke structure 61-63, electromagnetic waves incident into the interior through the gap G2 are reflected, canceling out the electromagnetic waves from the gap G1 at the gap G2, thereby preventing leakage of electromagnetic waves. The number and structure of the choke structures 61-63 are not limited to the structure of this embodiment.

[0062] The ventilation device 14 includes a first fan unit 66 for ventilating the first shielded space 71 and a second fan unit 67 for ventilating the second shielded space 72.

[0063] The first fan unit 66 includes a lower supply fan 66b that supplies air to the first shielded space (internal space of the lower compartment) 71 through a lower inlet 44, and a lower exhaust fan 66a that exhausts air from the first shielded space 71 through a lower outlet 43. Each fan 66a and 66b is provided on the outer surface of the first opposing shielded section 42.

[0064] The second fan unit 67 includes an upper supply fan 67b that supplies air to the second shielded space (internal space of the upper compartment) 72 through an upper inlet 49, and an upper exhaust fan 67a that exhausts air from the second shielded space 72 through an upper outlet 48. Each fan 67a and 67b is provided on the outer surface of the second opposing shielded section 47.

[0065] [Operation of electromagnetic heating device] The operation of the processing system, including the electromagnetic wave heating device 10, will be explained. When the power to the processing system is turned ON, the power to the electromagnetic wave heating device 10 and the transport mechanism 5 are also turned ON. As a result, the substrate 1 is transported by the transport mechanism 5, and electromagnetic waves are emitted from the oscillator 11. The substrate 1 is transported with the side facing the object to be heated 2 facing upwards, and a small distance from the first comb-tooth electrode 31 and the second comb-tooth electrode 32, through the gap G1. The ventilation device 14 is also operated. The substrate 1 may also be transported with the side facing the object to be heated 2 facing downwards.

[0066] In the electromagnetic wave heating device 10, electromagnetic waves output from the oscillator 11 are supplied to the first field formation circuit 20. Here, the wavelength λ of the electromagnetic waves from the oscillator 11 is, for example, between 50 mm and 75 cm. The frequency of the electromagnetic waves within this numerical range is in the microwave band between 400 MHz and 6 GHz. Examples of frequencies are 915 MHz and 2.45 GHz.

[0067] The length L1 of the first conductor line 31a is designed using Equation 1 (where n is a natural number), taking into account that the electrical length of the electromagnetic wave supplied to the first conductor line 31a is shortened from the wavelength λ at the oscillator 11. Similarly, the length L2 of the second conductor line 32a is designed using Equation 2 (where m is a natural number). In this embodiment, α = 0.6, but α = 0.8 is also possible. For example, n ≤ 5 and m ≤ 5. Note that both the length L1 of the first conductor line 31a and the length L2 of the second conductor line 32a include the portion where the line width widens at the base (see Figure 4). α×λ×(2n-1) / 4≦L1≦λ×(2n-1) / 4 (Formula 1) α×λ×(2m-1) / 4≦L2≦λ×(2m-1) / 4 (Formula 2)

[0068] In this embodiment, the first conductor line 31a and the second conductor line 32a are all the same length (L1=L2). However, the lengths of the first conductor line 31a and the second conductor line 32a may be different. Also, in this embodiment, the first conductor line 31a and the second conductor line 32a are the same width, but their widths may be different.

[0069] By setting the lengths L1 and L2 of the conductor lines 31a and 32a using equations 1 and 2, standing waves due to electromagnetic wave resonance are generated simultaneously at multiple locations in the electric field forming section 12. For example, the first electric field forming circuit 20 and the second electric field forming circuit 25 form a continuous electromagnetic wave path, and standing waves are generated simultaneously at multiple locations along this path. At locations where standing waves are generated, the electric field becomes stronger at the antinodes of the standing waves. In the electric field forming section 12, there are many antinodes of standing waves. Also, due to electric field coupling, electromagnetic waves propagate (power is transmitted) between adjacent conductor lines 31a and 32a. Furthermore, when the frequency of the oscillator 11 is set to 400 MHz or more and 6 GHz or less, the electric field at the ends of each conductor line 31a and 32a becomes stronger due to the edge effect. As a result, in the heating region, there are many dispersed locations with particularly strong electric fields, while the overall electric field becomes stronger. Therefore, the electromagnetic waves are effectively absorbed by the object to be heated 2.

[0070] The first field forming circuit 20 can be designed such that equation 3 holds true, with x1 being the number of first conductor lines 31a. The second field forming circuit 25 can be designed such that equation 4 holds true, with x2 being the number of second conductor lines 32a. L1×x1≧5λ···(Formula 3) L2×x2≧5λ···(Formula 4)

[0071] [Effects of the embodiment, etc.] In this embodiment, during the input period, standing waves due to electromagnetic wave resonance are simultaneously generated at multiple locations in the electric field forming section 12. Furthermore, since the array region of the first conductor line 31a and the array region of the second conductor line 32a face each other with a narrow gap between them, electromagnetic waves propagate between the first conductor line 31a and the second conductor line 32a. As a result, in the inter-circuit region 30, the electric field in the middle of the gap G1 in the height direction becomes relatively strong. When heating the object to be heated 2 on the substrate 1, heating efficiency is ensured even when the substrate 1 is passed through the middle of the gap G1. According to this embodiment, in an electromagnetic wave heating device 10 that can be used to heat the object to be heated 2 on the substrate 1, it is possible to ensure the heating efficiency of the object to be heated 2 while suppressing friction of the substrate 1 with the electric field forming circuits 20, 25.

[0072] In the present embodiment, heat generation (electrode heat generation) occurs in each of the electric field forming circuits 20 and 25. In particular, since resonance of electromagnetic waves is caused, each of the electric field forming circuits 20 and 25 is locally heated to a high temperature. Here, if a heat dissipation path is not provided for each of the electric field forming circuits 20 and 25, there is a possibility that extremely high temperature parts may be formed in each of the electric field forming circuits 20 and 25, and discharge triggered by thermionic emission from each of the electric field forming circuits 20 and 25 is likely to occur. When discharge occurs, if the base material 1 is a film, the base material 1 may be softened or melted, and the metal electric field forming circuits 20 and 25 may also be deformed or melted.

[0073] In contrast, in the present embodiment, the first ground electrode 40 is used as a heat dissipation path for heat generated in the first electric field forming circuit 20, and the second ground electrode 45 is used as a heat dissipation path for heat generated in the second electric field forming circuit 25. The heat dissipation side frame-shaped portions 41 and 46 of the respective ground electrodes 40 and 45 are in surface contact with the circuit side frame-shaped portions 21 and 26 of the respective electric field forming circuits 20 and 25 over the entire circumference. Therefore, the amount of heat transferred from the electric field forming circuits 20 and 25 to the ground electrodes 40 and 45 is relatively large, and a large amount of heat can be released to the outside from the facing shielding portions 42 and 47 connected to the heat dissipation side frame-shaped portions 41 and 46. Accordingly, temperature rise of each of the electric field forming circuits 20 and 25 and occurrence of discharge can be suppressed.

[0074] Further, in the present embodiment, the electromagnetic wave density (S / P) obtained by dividing the output power P of the oscillator 11 by the area S of the inter-circuit region 30 in plan view is 25 W / cm 2 or less. Here, as a result of intensive studies, the inventor of the present application found that when the electromagnetic wave density in the inter-circuit region 30 exceeds 25 W / cm 2 , discharge is likely to occur in the metal electric field forming circuit 20. Therefore, in the present embodiment, a value at which discharge is less likely to occur is employed as the value of electromagnetic wave density. The electromagnetic wave density can be lowered by increasing the area of each of the electric field forming circuits 20 and 25 without changing the output power of the oscillator 11. According to the present embodiment, the frequency of discharge occurrence in the inter-circuit region 30 can be reduced. Note that when there is a possibility of discharge between the base material 1 or the object to be heated 2 and the electric field forming circuit 20 due to physical properties and shape, the electromagnetic wave density is set to 8 W / cm 2The following is preferable: 4 W / cm 2 The following are even more desirable.

[0075] In this embodiment, the operation of each fan unit 66, 67 supplies cooling air to the field forming circuits 20, 25. Therefore, the temperature rise and discharge of each field forming circuit 20, 25 can be further suppressed.

[0076] In this embodiment, as the object to be heated 2 is heated, moisture evaporates from the object to be heated 2, causing the humidity in the second shielding space 72 above to rise particularly. If water vapor is not discharged from the second shielding space 72, condensation may occur, potentially adversely affecting the object to be heated 2. In contrast, in this embodiment, a second fan unit 67 is provided to ventilate the second shielding space 72, thereby suppressing the rise in humidity in the second shielding space 72. According to this embodiment, adverse effects of water vapor on the object to be heated 2 can be suppressed.

[0077] In this embodiment, a first fan unit 66 is also provided to ventilate the first shielding space 71. If the first fan unit 66 is not provided, the temperature and pressure differences between the front and back surfaces of the substrate 1 will be large. This will cause distortion in the substrate 1, making it easier for the substrate 1 to come into contact with the electric field forming circuits 20 and 25. In contrast, in this embodiment, since the first fan unit 66 is also provided, the temperature and pressure differences between the front and back surfaces of the substrate 1 will not be large. Therefore, it is possible to suppress contact between the substrate 1 and the electric field forming circuits 20 and 25 due to the temperature and pressure differences between the front and back surfaces of the substrate 1.

[0078] In this embodiment, the distance D1 between the first conductor line 31a and the first opposing shielding section 42 is equal to the distance D between the first conductor line 31a and the second conductor line 32a. G It is more than three times, and the distance D2 between the second conductor line 32a and the second opposing shielding section 47 is also greater than the distance D GThis is more than three times greater. Therefore, electromagnetic wave propagation in the height direction is predominantly between the first comb electrode 31 and the second comb electrode 32. Electromagnetic waves do not propagate easily between the comb electrodes 31, 32 and the opposing shielding parts 42, 47, and the contribution of each ground electrode 40, 45 to electric field formation is small. Consequently, the heating efficiency of the object to be heated 2 in the middle of the gap G1 can be improved.

[0079] Furthermore, in this embodiment, since distances D1 and D2 are relatively large, the air pressure loss in the shielded spaces 71 and 72 during the operation of the fan units 66 and 67 can be reduced. This allows the air from the fan units 66 and 67 to circulate more easily over a wider area, which is useful for cooling the substrate 1 and suppressing distortion of the substrate 1. It also allows for the rapid discharge of water vapor generated from the heated object 2 to the outside.

[0080] [Modified Example of Embodiment 1] In this modified example, the lengths L1 and L2 of each conductor line 31a and 32a are set to be at least 1.3 times the width W of the base material 1, thereby ensuring the distance from both ends of each conductor line 31a and 32a to the base material 1. The base material 1 is positioned near the center in the width direction such that, in a plan view, the distance from each end of the conductor lines 31a and 32a is approximately equal.

[0081] Here, Figure 5(A) shows the first electric field forming circuit 20, where the length L1 of the first conductor line 31a is approximately 1.1 times the width W of the base material 1. Since the base material 1 is transparent, the first electric field forming circuit 20 that overlaps the base material 1 is represented by a solid line. If L1 = L2 as in the embodiment described above, the length L2 of the second conductor line 32a is also approximately 1.1 times the width W of the base material 1. In this case, the distance from the ends of each conductor line 31a, 32a to the ends of the base material 1 is short, and the ends of the base material 1 are close to the points in each conductor line 31a, 32a where the electric field is particularly strong. The electric field is also likely to be strong at the ends of the base material 1. Therefore, discharge is likely to occur near the ends of the base material 1. Similarly, the electric field is also likely to be strong at the ends of the object to be heated 2, and discharge is likely to occur there as well.

[0082] In contrast, in this modified example, as shown in Figure 5(B), the lengths L1 and L2 of each conductor line 31a and 32a are set to be 1.3 times or more the width W of the base material 1. For example, if the width W of the base material 1 is 50 mm, the lengths L1 and L2 of each conductor line 31a and 32a can be set to 80 mm (in this case, the lengths L1 and L2 are 1.5 times or more the width W). Regarding these lengths L1 and L2, when the frequency of the electromagnetic wave at the oscillator 11 is 2.45 GHz (wavelength λ is 122 mm), the length L1 is included in the range when n=2 in the above equation 1 (55 mm to 92 mm), and the length L2 is included in the range when m=2 in the above equation 2 (55 mm to 92 mm). In this modified example, the distance from the ends of each conductor line 31a and 32a to the ends of the base material 1 is ensured, and the occurrence of discharge can be suppressed. Similarly, the distance to the ends of the object to be heated 2 is also ensured, and the occurrence of discharge can be suppressed.

[0083] [Second modified example of the embodiment] In this modified example, as shown in Figures 6(A) and 6(B), the conductor lines 31a and 32a are provided with width-changing sections in the middle, which include a narrow section (node) 33 where the width is locally narrowed and a wide section 34 where the width is locally widened. In this modified example, one width-changing section 33 or 34 is provided for each conductor line 31a or 32a. The width-changing sections 33 or 34 are located near the middle of the conductor lines 31a or 32a in the longitudinal direction. Note that multiple width-changing sections 33 or 34 may be provided for each conductor line 31a or 32a.

[0084] In this modified example, the electric field tends to concentrate not only at both ends of the conductor lines 31a and 32a, but also at the width change sections 33 and 34, thus strengthening the electric field near the middle of the conductor lines 31a and 32a. As a result, the electric field strength in the inter-circuit region 30 is made uniform, and uneven heating of the object to be heated 2 can be suppressed.

[0085] In Figures 6(A) and 6(B), width-changing sections 33 and 34 are provided on all conductor lines 31a and 32a, but width-changing sections 33 and 34 may be provided on only a portion of the conductor lines 31a and 32a. Also, width-changing sections 33 and 34 may be provided on both the first conductor line 31a and the second conductor line 32a, or on only one of them.

[0086] As shown in Figure 6(C), instead of the width-changing sections 33 and 34, a bent section 35 that protrudes laterally may be provided in the middle of the first conductor line 31a. Although not shown, a bent section 35 may also be provided in the middle of the second conductor line 32a. One bent section 35 may be provided for each conductor line 31a, 32a, or multiple bent sections 35 may be provided. The bent section 35 may be provided for all conductor lines 31a, 32a, or for only a part of the conductor lines 31a, 32a. The bent section 35 may also be provided for both the first conductor line 31a and the second conductor line 32a, or for only one of them.

[0087] Although not shown in the diagram, a thickness-changing section may be provided in the middle of the conductor lines 31a and 32a, where the thickness changes locally. The thickness-changing section may be a part where the thickness increases locally, or a part where the thickness decreases locally.

[0088] [Third Modification of the Embodiment] In this modified example, frequency tracking control is performed to control the oscillation frequency of the oscillator 11 so that it follows the resonance frequency of the electromagnetic wave in the field forming unit 12.

[0089] In this modified example, frequency tracking control is performed based on the difference between the phase of the incident electromagnetic wave traveling from the oscillator 11 to the input unit 15 and the phase of the reflected electromagnetic wave returning from the input unit 15 to the oscillator 11. For this frequency tracking control, the control method described in Japanese Patent Application Publication No. 2022-183636 can be used.

[0090] In this case, as shown in Figure 7, the electromagnetic wave heating device 10 further includes a signal extraction unit 91 that extracts reflected wave information representing the waveform of the reflected wave returning from the input unit 15 in the electromagnetic wave transmission line 90, a phase difference information generation unit 92 that generates phase difference information representing the phase difference between the incident wave and the reflected wave through calculation processing using incident wave information representing the waveform of the incident wave and the reflected wave information, and a control unit 93 that repeatedly performs control processing to detect the direction of adjustment of the oscillation frequency using the phase difference information and to control the oscillation frequency based on the detected adjustment direction. A directional coupler can be used in the signal extraction unit 91.

[0091] In this modified example, the signal extraction unit 91 extracts not only reflected wave information but also incident wave information. The incident wave information can also be the phase at the output timing of the electromagnetic wave of the oscillator 11. A phase detector or an amplitude-phase detector can be used in the phase difference information generation unit 92.

[0092] The control unit 93 detects the direction of oscillation frequency adjustment that reduces the difference between the resonant frequency in the electric field formation unit 12 and the oscillation frequency of the oscillator 11, based on reference information of the state in which the phase of the incident wave and the phase of the reflected wave are equal, and phase difference information generated by the phase difference information generation unit. For example, the control unit 93 compares the phase difference voltage V with respect to a threshold range (-Vc to Vc) that includes a threshold (voltage = 0). If the phase difference voltage V falls below the lower limit of the threshold range -Vc, the control unit 93 controls the oscillator 11 to increase the oscillation frequency, and if the phase difference voltage V exceeds the upper limit of the threshold range Vc, the control unit 93 controls the oscillator 11 to decrease the oscillation frequency.

[0093] Frequency tracking control may also be performed based on the intensity of the reflected electromagnetic waves returning from the input unit 15 to the oscillator 11. In this case, the intensity of the reflected waves is detected from the reflected wave information extracted by the signal extraction unit 91, and feedback control is sequentially performed to control the oscillation frequency of the oscillator 11 so that the detected intensity of the reflected waves decreases.

[0094] [Fourth modified example of the embodiment] In this modified example, as shown in Figure 8, the electric field forming unit 12 is provided with multiple input units 15u, 15d (two input units 15u, 15d in this modified example), and oscillators 11u, 11d are connected to each of them. Furthermore, the phases of the electromagnetic waves between the multiple oscillators 11u, 11d are made to be different from each other. As a result, in the electric field forming circuits 20, 25, the electromagnetic waves from the upstream oscillator 11u and the electromagnetic waves from the downstream oscillator 11d interfere with each other, resulting in an irregular composite wave, which can suppress uneven heating in the width direction of the object to be heated 2. The phases of each oscillator 11u, 11d may also be electrically changed. As a result, the density of electromagnetic waves in the electric field forming unit 12 changes, altering the heating distribution, which can suppress uneven heating in the width direction of the object to be heated 2.

[0095] [Other embodiments] In this embodiment, the upper field forming circuit may be designated as the first field forming circuit, and the lower field forming circuit may be designated as the second field forming circuit.

[0096] In this embodiment, the signal line 15a of the input unit 15 may be connected to the second field forming circuit 25 instead of the first field forming circuit 20. Alternatively, two input units 15 may be provided, with the signal line 15a of each input unit 15 connected to the first field forming circuit 20 and the second field forming circuit 25, respectively. Furthermore, the signal lines 15a of both input units 15 may both be connected to either the first field forming circuit 20 or the second field forming circuit.

[0097] In this embodiment, the grounding conductor 15b of the input section 15 may be connected to the second field forming circuit 25 instead of the first field forming circuit 20, or it may be connected to each of the first field forming circuit 20 and the second field forming circuit 25.

[0098] In this embodiment, the ground electrodes 40 and 45 are in contact with each of the electric field forming circuits 20 and 25, but the ground electrodes 40 and 45 may be spaced apart from each of the electric field forming circuits 20 and 25.

[0099] In this embodiment, the second direction is the same as the first direction, but the second direction may be different from the first direction. In this case, the first conductor line 31a and the second conductor line 32a intersect in a plan view.

[0100] In the above-described embodiment, the electromagnetic wave heating device 10 may heat the object to be heated 2 without transporting the object to be heated 2.

[0101] In the above-described embodiment, the direction of the air supplied from the fan units 66 and 67 can be any direction. In the above-described embodiment, inlets 44 and 49 are provided on the upstream side and outlets 43 and 48 are provided on the downstream side, but outlets 43 and 48 may be provided on the upstream side and inlets 44 and 49 on the downstream side. Also, all the air passages provided in the ground electrodes 41 and 42 may be outlets, in which case air is introduced through the gaps G1 and G2. Also, all the air passages provided in the ground electrodes 41 and 42 may be inlets, in which case air is discharged through the gaps G1 and G2.

[0102] In the embodiment described above, the first shield portion 51 and the second shield portion 52 may be reversed vertically.

[0103] In the above-described embodiment, the electromagnetic wave heating device 10 may include a waste heat utilization unit 80 that uses the waste heat from the oscillator 11 to heat the air supplied to the object to be heated 2 by the fan unit 66, as shown in Figure 9. The waste heat utilization unit 80 includes, for example, a heat dissipation unit 81 that dissipates the heat generated by the oscillator 11 during operation, and a case 82 that houses the heat dissipation unit 81 between the inlet 83 and the outlet 84, with an air inlet 83 and an air outlet 84, respectively. The heat dissipation unit 81 is, for example, a plurality of heat dissipation fins thermally connected to the heat-generating part of the oscillator 11. External air flows into the inlet 83 of the case 82. The outlet 84 of the case 82 is connected to the intake port of the lower air supply fan 66b. As a result, the air heated in the case 82 is supplied by the lower air supply fan 66b mainly to the back side of the base material 1, thereby heating the object to be heated 2. If the base material 1 is transported with the side facing the object to be heated 2 facing downwards, the heated air will directly heat the object to be heated 2. Alternatively, a connecting passage may be provided between the outlet 84 of the case 82 and the intake port of the upper supply fan 67b so that the air heated inside the case 82 is supplied to the second field forming circuit 25 side to which the oscillator 11 is not connected. [Industrial applicability]

[0104] The present invention is applicable to electromagnetic wave heating devices and the like used for heating objects. [Explanation of symbols]

[0105] 1 Base material 2 Object to be heated 10 Electromagnetic heating device 11 Oscillator 12. Electric field forming section 13 Frame-shaped shield section 14. Ventilation system 15 Input section 20 First field formation circuit 25. Second field formation circuit 30 Intercircuit area 31 1st comb electrode 31a First conductor line 32 Second comb electrode 32a Second conductor line 40 First grounding electrode 45 Second grounding electrode

Claims

1. An electromagnetic wave heating device that heats an object using electromagnetic waves, A first electric field forming circuit having a plurality of first conductor lines arranged with gaps in the first direction, A second electric field forming circuit having a plurality of second conductor lines arranged with gaps in the second direction, wherein the arrangement region of the second conductor lines faces the arrangement region of the first conductor lines with a gap between them, The system includes an input unit that inputs electromagnetic waves transmitted through an unbalanced transmission line to an electric field forming unit including the first electric field forming circuit and the second electric field forming circuit, An electromagnetic wave heating device wherein, during the input period in which electromagnetic waves are input to the input section, standing waves due to the resonance of electromagnetic waves are generated at multiple locations in the electric field forming section, and a strong electric field region for heating an object to be heated is formed in the inter-circuit region sandwiched between the first electric field forming circuit and the second electric field forming circuit.

2. The first ground electrode is provided in contact with the first electric field forming circuit, The electromagnetic wave heating device according to claim 1, wherein the first ground electrode is formed as an electromagnetic wave shielding structure to shield the side of the first electric field forming circuit opposite to the inter-circuit region.

3. The arrangement region of the first conductor line and the arrangement region of the second conductor line are parallel to each other. The first ground electrode faces the plurality of first conductor lines on the side opposite to the inter-circuit region and has a facing shielding portion that forms a shielding space between itself and the plurality of first conductor lines. The electromagnetic wave heating device according to claim 2, wherein, in a direction perpendicular to the arrangement region of the first conductor lines, the distance between the first conductor line and the opposing shielding portion is three times or more the distance between the first conductor line and the second conductor line.

4. The input unit inputs the electromagnetic wave transmitted through the unbalanced transmission line to the first electric field forming circuit. The first electric field forming circuit has a base line to which one end of each of the plurality of first conductor lines is connected, The electromagnetic wave heating device according to claim 1, further comprising a heat dissipation member having a linear contact portion provided along the base line and in contact with the base line, which dissipates heat from the base line through the linear contact portion.

5. The first electric field forming circuit includes the base line in part and has a circuit-side frame-shaped portion that surrounds the plurality of first conductor lines, spaced apart from the other end of each of the plurality of first conductor lines. The electromagnetic wave heating device according to claim 4, wherein the heat dissipation member includes the linear contact portion in part and has a heat dissipation side frame-shaped portion that contacts the circuit side frame-shaped portion over its entire circumference.

6. A first ground electrode in contact with the first electric field forming circuit, The electromagnetic wave heating device according to claim 1, further comprising a second ground electrode in contact with the second electric field forming circuit.

7. The system further includes an oscillator that outputs electromagnetic waves toward the aforementioned input section, The electromagnetic wave heating device according to claim 1, wherein equation 1 holds true when the wavelength of the electromagnetic wave in the oscillator is λ and the length of the first conductor line is L1. α×λ×(2n-1) / 4≦L1≦λ×(2n-1) / 4...(Formula 1) Here, α is 0.6 and n represents a natural number.

8. The system further includes an oscillator that outputs electromagnetic waves toward the aforementioned input section, The electromagnetic wave density obtained by dividing the output power of the oscillator by the area of ​​the inter-circuit region in a plan view is 25 W / cm². ２ The electromagnetic wave heating device according to claim 1, which is as follows:

9. The upper of the first and second electric field forming circuits is designated as the upper electric field forming circuit, and the lower of the two electric field forming circuits is designated as the lower electric field forming circuit. It is formed in a box shape with an opening on the lower side, and the opening is closed by the upper electric field forming circuit, and the upper compartment has an upper inlet and an upper outlet as an air passage, The electromagnetic wave heating device according to claim 1, further comprising an upper exhaust fan that exhausts air from the inside of the upper compartment through the upper exhaust port.

10. The electromagnetic wave heating device according to claim 9, further comprising an upper air supply fan that supplies air to the interior of the upper compartment through the upper inlet.

11. It is formed in a box shape with an opening on the upper side, and the opening is closed by the lower electric field forming circuit, and the lower compartment has a lower inlet and a lower outlet as an air passage, The electromagnetic wave heating device according to claim 9, further comprising a lower exhaust fan that exhausts air from the inside of the lower compartment through the lower exhaust port.

12. The electromagnetic wave heating device according to claim 1, wherein the first conductor line and / or the second conductor line are provided with a width-changing section in which the width locally changes, a thickness-changing section in which the thickness locally changes, or a bent section that is bent to protrude laterally.

13. The electromagnetic wave heating device according to claim 1, wherein the second direction is the same direction as the first direction.

14. The electric field forming portion is further provided with a frame-shaped shielding portion to prevent electromagnetic wave leakage from the gap in the inter-circuit region, The electromagnetic wave heating device according to claim 1, wherein the frame-shaped shield portion is provided with a choke structure.

15. An oscillator that outputs electromagnetic waves toward the aforementioned input section, The electromagnetic wave heating device according to claim 1, further comprising: (i) a control unit that controls the oscillation frequency of the oscillator to follow the resonant frequency of the electromagnetic wave in the electric field forming unit, based on the intensity of the reflected electromagnetic wave returning from the input unit to the oscillator, or (ii) the difference between the phase of the incident electromagnetic wave going from the oscillator to the input unit and the phase of the reflected electromagnetic wave returning from the input unit to the oscillator.

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