WO2015022857A1 - Infrared radiation device and infrared treatment device - Google Patents

Abstract

An infrared radiation device (20) is provided with an infrared heater unit (30) having a filament (32) radiating an electromagnetic wave containing infrared when heated, a lower wall part (61) reflecting upward an infrared beam radiated directly below from the filament (32) when a predetermined direction is downward, and a reflective body (62) having a reflective surface (63) reflecting an infrared beam radiated upward from the filament (32) so as to reach lower than the lower wall part (61). An insulation container (60) is provided with a second flow path (67) allowing a second refrigerant to flow through. The infrared radiation device (20) is provided with side wall parts (64a to 64d) for blocking an infrared beam radiated from the filament (32) in a front, back, left or right direction, orthogonal to the downward direction. The infrared radiation device (20) is provided with the insulation container (60) covering the filament (32), and the insulation container (60) has a hole (65) serving as an exit from the insulation container (60) for an infrared beam.

Description

Infrared radiation device and infrared processing device

The present invention relates to an infrared radiation device and an infrared processing device.

Conventionally, an infrared radiation device that emits infrared light to a processing target such as a coating film is known. For example, Patent Document 1 discloses a rod-shaped heating element made of carbon or silicon carbide that emits infrared rays when heated, and a cylindrical protective tube made of translucent alumina ceramic in which the heating element is hermetically accommodated. An infrared heater provided is described. This protective tube has a total transmittance of electromagnetic waves having a wavelength of 0.4 to 6 μm of 80% or more.

JP 2006-294337 A

By the way, in such an infrared radiation device, the radiant energy distribution (in-plane distribution) on the surface to be processed may be non-uniform, for example, the portion of the surface to be processed that is closer to the heating element has higher radiant energy. there were. In order to enable more uniform processing (for example, drying), there has been a demand for improving the in-plane uniformity of infrared radiation energy.

The present invention has been made to solve such a problem, and has as its main object to improve the in-plane uniformity of infrared radiation energy to the object to be treated.

The infrared radiation device of the present invention is
A heating element that emits electromagnetic waves including infrared when heated,
A lower shield that reflects upward the infrared rays emitted directly from the heating element when the predetermined direction is a downward direction;
A reflector having a reflecting surface for reflecting infrared rays radiated upward from the heating element so that the infrared rays can reach below the lower shield;
It is equipped with.

In the infrared radiation device of the present invention, when an electromagnetic wave including infrared rays is radiated from the heating element, the infrared radiation radiated directly from the heating element is reflected and shielded upward by the lower shielding body. On the other hand, the infrared rays radiated upward from the heating element are reflected by the reflecting surface of the reflector and reach below the lower shield. That is, the infrared rays that go directly below the heating element are reflected by the lower shielding body, and the infrared rays that are reflected by the reflecting surface reach below. For this reason, compared with the case where it does not have a lower shielding body, the in-plane uniformity of the infrared radiation energy radiated | emitted below the heat generating body (below a lower shielding body) improves. Therefore, it is possible to improve the in-plane uniformity of infrared radiation energy to the processing object disposed below. In addition, the infrared rays radiated directly below the heating element are reflected by the lower shielding body and further reflected by the reflecting surface of the reflecting body, so that the infrared rays can reach the lower part of the lower shielding body. Therefore, for example, compared with the case where the lower shield absorbs infrared rays without reflecting the infrared rays, the infrared rays from the heating element can be efficiently emitted to the processing target. Here, “downward direction” is a convenient name for “predetermined direction” (reference direction). Therefore, the “downward direction” may be, for example, a vertically downward direction, a vertically upward direction, or any other direction. For example, when the heating element is a long object, the direction perpendicular to the longitudinal direction of the heating element may be set as the “predetermined direction” (= downward direction). It is assumed that the upper direction and the left-right direction are determined based on the “downward direction”. Further, “downward” means not only directly below but also diagonally below. “Upward” means not only directly above but also diagonally above. “Reflecting infrared rays” may be anything as long as it reflects at least a portion of infrared rays. For example, a portion of infrared rays may be absorbed or transmitted. It is preferable that the lower shield has a higher infrared reflectance. For example, the lower shield may have an infrared reflectance of 50% or more from the heating element, may exceed 50%, may be 80% or more, or 90% or more. Similarly, the “reflecting surface” only needs to reflect at least part of infrared rays, and may absorb or transmit part of infrared rays, for example. It is preferable that the reflection surface has a higher infrared reflectance. For example, the reflective surface may have an infrared reflectance of 50% or more, may exceed 50%, may be 80% or more, or 90% or more. In addition, the lower shield is not limited to the infrared radiation radiated directly from the heating element, and may be capable of reflecting upward the infrared radiation radiated downward from the heating element.

In the infrared radiation device of the present invention, the reflecting surface may be wider in the left-right direction, which is a direction perpendicular to the lower direction, than the heating element. Further, the reflecting surface may be wider in the left-right direction, which is a direction perpendicular to the lower direction, than the lower shield. The left-right direction may be a direction perpendicular to the longitudinal direction of the heating element and perpendicular to the lower direction. Furthermore, the infrared radiation device of the present invention may include a reflector coolant channel through which a coolant for cooling the reflector can be circulated. If it carries out like this, overheating by a reflector absorbing a part of infrared rays can be suppressed.

In the infrared radiation device of the present invention, the reflection surface may be a surface that irregularly reflects the infrared light. In this way, the in-plane uniformity of the infrared radiation energy to the processing target can be further improved. In addition, since infrared rays can be irregularly reflected more reliably, the reflection surface may have an arithmetic average roughness Ra equal to or greater than the wavelength of infrared rays. For example, the reflective surface may have an arithmetic average roughness Ra of 3.5 μm or more, which is the maximum value of the near-infrared (wavelength 0.7 μm to 3.5 μm) wavelength.

The infrared radiation device of the present invention may include a side shield that shields infrared radiation emitted from the heating element in a direction perpendicular to the downward direction. If it carries out like this, it can suppress more that the infrared rays radiated | emitted from a heat generating body reach | attain directly to a process target without reflection. Thereby, the in-plane uniformity of the infrared radiation energy to a process target can be improved more. Here, “shielding infrared rays” may be anything that shields (does not transmit) at least part of infrared rays, and includes, for example, the case of absorbing or reflecting infrared rays. The said side part shield is so preferable that the transmittance | permeability of infrared rays is low. For example, the side shield may have an infrared transmittance of 50% or less, less than 50%, or 20% or less, or 10% or less. The side shield may be configured to shield infrared rays in two or more directions in a direction perpendicular to the lower direction when viewed from the heating element. The infrared radiation device of the present invention may include a plurality of the side shields.

In the infrared radiation device according to the aspect of the present invention including a side shield, the reflector, the lower shield, and the side shield, and including a shielding container that covers the heating element, The shielding container has a radiation port that is formed at a position other than directly below the heating element and serves as an outlet for the infrared light from the shielding container when the infrared light reflected by the reflecting surface reaches below the lower shielding body. You may have. If it carries out like this, the in-plane uniformity of the infrared radiation energy to the process target arrange | positioned under the radiation port can be improved. Moreover, since the heating element is covered with the shielding container, it is possible to further suppress the infrared rays radiated from the heating element from directly reaching the processing target without reflection. In this case, the radiation port may have a shape or an arrangement such that infrared rays radiated from the heating element cannot pass through the radiation port without being reflected. In this way, the infrared radiation from the heating element can be prevented from passing directly through the radiating port without reflection and reaching the processing target directly, and the in-plane uniformity of the infrared radiation energy radiated to the processing target. Can be further improved.

In the infrared radiation device of the present invention having a shielding container, the lower shielding body and the side shielding body may be configured such that a surface on the heating element side can reflect infrared rays from the heating element. If it carries out like this, at least one part of the infrared rays radiated | emitted from the heat generating body will be radiated | emitted from a radiation | emission port, after being reflected in the shielding container in multiple times. Therefore, the in-plane uniformity of the infrared radiation energy radiated from the radiation port to the object to be processed can be further improved. In this case, any inner peripheral surface of the shielding container excluding the radiation port may reflect infrared rays.

The infrared radiation device of the present invention including a shielding container may include a shielding container coolant channel through which a coolant for cooling the shielding container can flow. If it carries out like this, overheating of the shielding container by infrared rays can be suppressed more by a refrigerant | coolant. In this case, the infrared radiation device of the present invention includes a tubular member that is disposed inside the shielding container, transmits infrared rays from the heating element, and covers the heating element. It may be a space between the shielding container and the tubular member. Further, the radiation port may be an opening communicating with the outside of the shielding container and the refrigerant flow path for the shielding container. If it carries out like this, while being able to cool a shielding container with a refrigerant | coolant, a refrigerant | coolant can be flowed out downward from a radiation | emission opening. Therefore, by circulating gas as the refrigerant, the refrigerant can serve as both cooling of the shielding container and blowing air to the processing target.

In the infrared radiation device of the present invention including a shielding container, the shielding container may include a partition member that transmits infrared rays and closes the radiation port to partition the inside and outside of the shielding container. Furthermore, the partition member may be formed of a material that transmits infrared rays having a wavelength of 3.5 μm or less and absorbs infrared rays having a wavelength exceeding 3.5 μm. Infrared rays having a wavelength of 3.5 μm or less are excellent in the ability to break hydrogen bonds in molecules such as water and solvents. Therefore, the partition member selectively transmits infrared rays having a wavelength of 3.5 μm or less, so that the processing target can be efficiently processed (for example, dried or dehydrated).

The infrared radiation device of the present invention having a shielding container has an inner circumferential surface along the vertical direction, and the infrared radiation reflected by the reflecting surface is reflected by the inner circumferential surface so that the infrared radiation is emitted from the radiation port. A waveguide leading to By doing so, at least a part of the infrared rays emitted from the heating element is reflected from the inner peripheral surface of the waveguide and then emitted from the radiation port. Therefore, the in-plane uniformity of the infrared radiation energy radiated from the radiation port to the object to be processed can be further improved. In this case, the lower end of the waveguide may be the radiation port. The inner peripheral surface of the waveguide may be capable of totally reflecting infrared rays. In this way, infrared rays can be radiated to the processing target more efficiently. The inner peripheral surface of the waveguide may be capable of totally reflecting infrared rays having a wavelength of 3.5 μm or less. The waveguide may have a shape and an arrangement such that infrared rays radiated from the heating element cannot reach the radiation opening without being reflected. In this way, the infrared rays from the heating element do not pass directly through the radiating port without reflection and reach the object to be processed, so that the in-plane uniformity of the infrared radiation energy radiated to the object to be processed is further improved. Can be improved.

In the infrared radiation device of the present invention having a shielding container, a plurality of the heating elements may be disposed in the shielding container, and may be disposed on both sides of the radiation opening in a direction perpendicular to the vertical direction. In this way, since infrared rays can be emitted from a plurality of heating elements, the infrared radiation intensity from the emission port can be increased. In addition, since the heating elements are arranged on both sides of the radiating port in a direction perpendicular to the vertical direction, for example, the in-plane uniformity of the infrared radiation energy from the radiating port is improved as compared with the case where there is only one heating element. It can be improved further.

In this case, the shielding container is a rectangular parallelepiped container having an upper wall portion including the reflector, a lower wall portion including the lower shielding body, and four side wall portions including the side shielding body. A plurality of the heating elements are arranged in the shielding container, and are arranged between the four side wall portions in the shielding container and the radiation opening, respectively, and the radiation opening is formed in a direction perpendicular to the vertical direction. It may be located so as to surround the periphery of. In this case, since the heating element is arranged so as to surround the periphery of the radiation port, the in-plane uniformity of the infrared radiation energy from the radiation port can be further improved. The “cuboid” includes a substantially rectangular parallelepiped. The heating elements may be arranged in the vicinity of the four side wall portions.

The infrared radiation device of the present invention may include a tubular member that transmits infrared rays from the heating element and covers the heating element, and the lower shielding body may be formed on an inner peripheral surface or an outer peripheral surface of the tubular member. Good.

The infrared processing apparatus of the present invention includes the infrared radiation apparatus of the present invention according to any one of the above-described aspects, and performs processing by radiating infrared rays from the infrared radiation apparatus to a processing target positioned below the infrared radiation apparatus. It is.

Since the infrared processing apparatus of the present invention includes the infrared radiation apparatus of the present invention according to any one of the above-described aspects, the effects of the infrared radiation apparatus of the present invention, for example, in the plane of the infrared radiation energy to the processing target An effect of improving the uniformity can be obtained. In addition, the infrared processing apparatus of this invention is good also as what is processed in the state which stopped conveyance of the process target, and is good also as what is processed while conveying.

1 is a longitudinal sectional view of a drying furnace 10. FIG. 2 is a perspective view of an infrared radiation device 20. FIG. FIG. 3 is a sectional view taken along line BB in FIG. It is explanatory drawing which shows a mode that infrared rays are radiated | emitted from the infrared heater unit 30 single-piece | unit and the infrared radiation apparatus 20. FIG. It is a longitudinal cross-sectional view of the drying furnace 110 of the modification. It is a longitudinal cross-sectional view of the drying furnace 10 of a modification. It is a perspective view of the infrared rays radiating device 220 of a modification. It is a perspective view of the infrared rays radiating device 320 of a modification. It is a longitudinal cross-sectional view of the drying furnace 410 of a modification. It is a longitudinal cross-sectional view of the drying furnace 510 of a modification.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a drying furnace 10 which is an embodiment of the infrared processing apparatus of the present invention. The drying furnace 10 performs drying of the coating film 82 applied on the sheet 80 using infrared rays, and includes a furnace body 12, an infrared radiation device 20, and a controller 90. The drying furnace 10 is configured as a roll-to-roll drying furnace, and includes a roll 17 provided on the left side of the furnace body 12 (left side in FIG. 1) and a right side of the furnace body 12 (in FIG. 1). And a roll 18 provided on the right side). The drying furnace 10 transports the sheet 80 and carries the coating film 82 to be processed (drying target) formed on the upper surface of the sheet 80 into the furnace body 12, and transports the sheet 80 inside the furnace body 12. And an intermittent feed type drying furnace that alternately repeats the step of drying the coating film 82. In the present embodiment, the vertical downward direction is described as “downward”.

The furnace body 12 is a heat insulating structure formed in a substantially rectangular parallelepiped, and includes a drying space 12a which is an internal space, and an entrance to the drying space 12a from the outside formed in the left end surface 13 and the right end surface 14 of the furnace body, respectively. Openings 15 and 16 are formed. The furnace body 12 has a length from the left end surface 13 to the right end surface 14 of, for example, 1 m to 6 m. An infrared radiation device 20 and the like are disposed in a drying space 12a that is a space inside the furnace body 12.

The infrared radiation device 20 radiates infrared rays to dry the coating film 82 formed on the upper surface of the sheet 80. FIG. 2 is a perspective view of the infrared radiation device 20. 3 is a cross-sectional view taken along the line BB of FIG. The cross-sectional view of the infrared radiation device 20 in FIG. 1 corresponds to the cross-sectional view along AA in FIG. The infrared radiation device 20 includes a plurality (two in this embodiment) of infrared heater units 30 and a shielding container 60. Note that one infrared heater unit 30 is disposed at each of both ends (left and right ends in FIG. 1) in the shielding container 60, the right side is also referred to as an infrared heater unit 30a, and the left side is also referred to as an infrared heater unit 30b.

The infrared heater unit 30 ( infrared heater units 30a and 30b) is a device that emits infrared rays. The infrared heater units 30a and 30b are both attached so that the longitudinal direction is along the front-rear direction. Note that the front-rear direction is a direction orthogonal to the up-down direction and the left-right direction, and is the front-rear direction in FIG. Since both the infrared heater units 30a and 30b have the same configuration, the configuration of one infrared heater unit 30a will be described below.

As shown in FIGS. 1 and 3, the infrared heater unit 30 a includes a heater body 38 formed so that the inner tube 36 surrounds the filament 32, which is a heating element, and an outer body formed so as to surround the heater body 38. A tube 40, a bottomed cylindrical cap 42 that is airtightly fitted to both ends of the outer tube 40, and a first flow path 47 that is formed between the heater body 38 and the outer tube 40 and through which the first refrigerant can flow. It is equipped with.

The filament 32 is a heating element that emits infrared rays when heated, and is made of W (tungsten) in this embodiment. Other examples of the material of the filament 32 include Ni—Cr alloy, Mo, Ta, and Fe—Cr—Al alloy. When the filament 32 is supplied with electric power from the electric power supply source 50 and heated to 700 to 1700 ° C., for example, the filament 32 emits infrared rays having a peak in the infrared region having a wavelength of 3.5 μm or less (eg, near 3 μm). . The electric wiring 34 connected to the filament 32 is drawn out to the outside airtightly through a wiring drawing portion 44 provided in the cap 42 and penetrating the upper wall portion 62 of the shielding container 60, and is connected to the power supply source 50. . The inner tube 36 and the outer tube 40 are formed of an infrared absorbing material that functions as a filter that passes infrared rays having a wavelength of 3.5 μm or less among the electromagnetic waves radiated from the filament 32 and absorbs infrared rays having a wavelength exceeding 3.5 μm. ing. Examples of such infrared transmitting materials used for the inner tube 36 and the outer tube 40 include germanium, silicon, sapphire, calcium fluoride, barium fluoride, zinc selenide, zinc sulfide, chalcogenide glass, and transmissive alumina ceramics. Other examples include quartz glass that can transmit infrared rays. In this embodiment, both the inner tube 36 and the outer tube 40 are made of quartz glass.

The heater body 38 is supported at both ends by holders 49 arranged inside the cap 42. Each cap 42 has a first refrigerant inlet / outlet 46. The first refrigerant is supplied from the first refrigerant supply source 52 to one of the first refrigerant outlets 46. The first refrigerant that has flowed into the outer tube 40 from one first refrigerant inlet / outlet 46 flows through the first flow path 47 and flows out from the other first refrigerant inlet / outlet 46. The 1st refrigerant | coolant which flows through the 1st flow path 47 is gas, such as air and an inert gas, for example, and these are cooled by contacting the inner tube | pipe 36 and the outer tube | pipe 40 and taking heat away.

In the infrared heater unit 30a thus configured, when infrared rays having a peak at a wavelength of 3.5 μm or less are emitted from the filament 32, infrared rays having a wavelength of 3.5 μm or less pass through the inner tube 36 and the outer tube 40. And radiated into the inner space of the shielding container 60. The inner tube 36 and the outer tube 40 absorb infrared rays having a wavelength exceeding 3.5 μm, but are cooled by the first refrigerant flowing through the first flow path 47 and the second refrigerant flowing through the second flow path 67 described later. (For example, 200 degrees C or less), it can suppress that self becomes an infrared secondary radiator.

The shielding container 60 is a substantially rectangular parallelepiped member that covers the filament 32 of the infrared heater unit 30. The shielding container 60 includes a lower wall portion 61, an upper wall portion 62, and side wall portions 64a to 64d. The lower wall portion 61, the upper wall portion 62, and the side wall portions 64a to 64d are joined together by welding, for example. The internal space of the shielding container 60, that is, the space surrounded by the lower wall portion 61, the upper wall portion 62, and the side wall portions 64a to 64d serves as the second flow path 67 through which the second refrigerant for cooling the shielding container 60 can flow. Yes. A temperature sensor 56 for detecting the surface temperature of the shielding container 60 (lower wall portion 61) is attached to the lower surface of the lower wall portion 61 (see FIG. 3).

The lower wall portion 61 is a member configured as a lower shielding body that shields infrared rays emitted directly under the infrared heater units 30a and 30b. The lower wall portion 61 is positioned below including the infrared heater units 30a and 30b. The lower wall portion 61 is formed to be wider in the left-right direction than the infrared heater units 30a and 30b, and extends from the right side of the infrared heater unit 30a to the left side of the infrared heater unit 30b. ing. A plurality of holes 65 that are openings having a circular cross section communicating with the inside and outside of the shielding container 60 are formed at positions other than directly below the infrared heater units 30 a and 30 b in the lower wall portion 61. In the present embodiment, as shown in FIG. 2, a plurality of holes 65 are formed near the middle in the left-right direction between the infrared heater unit 30a and the infrared heater unit 30b. A plurality of holes 65 are formed in the left-right direction and the front-rear direction, respectively. In the present embodiment, the holes 65 are formed by arranging a total of 50 holes in 5 rows in the left-right direction and 10 rows in the front-rear direction in a substantially rectangular shape (see FIG. 2). The hole 65 serves as a radiation port serving as an outlet from the infrared shielding container 60 radiated from the infrared heater unit 30. The holes 65 have a shape and an arrangement such that infrared rays radiated from the filaments 32 of the infrared heater units 30a and 30b cannot pass through the holes 65 without reflection. In other words, the hole 65 is formed so that a path (virtual straight line) from the filament 32 through the hole 65 to reach the outside of the shielding container 60 cannot be drawn. For example, such a hole 65 is formed by adjusting the distance from the filament 32 to the hole 65, the opening cross-sectional area of the hole 65, the path length of the hole 65 (= thickness of the lower wall portion 61), and the like. Can do.

The upper wall portion 62 is a member configured as a reflector having a reflection surface 63 that reflects infrared rays. The upper wall 62 is located above the infrared heater units 30a and 30b. The upper wall portion 62 is formed to be wider in the left-right direction than the infrared heater units 30a and 30b, and extends from the right side of the infrared heater unit 30a to the left side of the infrared heater unit 30b. ing. The upper wall portion 62 is formed of an infrared reflecting material capable of reflecting infrared rays emitted from the infrared heater unit 30. Therefore, the upper wall portion 62 reflects the infrared rays from the infrared heater unit 30 downward on the reflection surface 63 that is a portion facing the internal space of the shielding container 60 (the lower surface of the upper wall portion 62). The reflection surface 63 is a surface along a substantially horizontal direction. Examples of the infrared reflecting material include SUS304 and aluminum. The reflection surface 63 only needs to reflect at least part of the infrared rays from the infrared heater unit 30, and may absorb or transmit part of the infrared rays, for example. The reflecting surface 63 is more preferable as the reflectance of infrared rays is higher. For example, the reflective surface 63 may have an infrared reflectance of 50% or more, may exceed 50%, may be 80% or more, or 90% or more. In particular, the reflectance of infrared rays having a wavelength of 3.5 μm or less emitted from the infrared heater unit 30 is preferably high, and the reflectance of infrared rays having a wavelength of 3.5 μm or less may be the above value.

The side wall portions 64a to 64d are members configured as side shields that shield infrared rays radiated from the infrared heater unit 30 in a direction perpendicular to the downward direction (front-rear and left-right directions). The side wall part 64a is located on the right side of the infrared heater unit 30a. The side wall part 64b is located on the left side of the infrared heater unit 30b. The side wall 64c is located in front of the infrared heater units 30a and 30b. The side wall 64d is located behind the infrared heater units 30a and 30b. The side wall portions 64a to 64d are formed wider in the vertical direction than the infrared heater units 30a and 30b.

The lower wall portion 61 and the side wall portions 64a to 64d are more preferable as the infrared transmittance is smaller. For example, the infrared transmittance from the filament 32 may be 50% or less, or 20% or less, or 10% or less. Further, in the present embodiment, the lower wall portion 61 and the side wall portions 64a to 64d are also formed of an infrared reflecting material like the upper wall portion 62. Therefore, the part (upper surface of the lower wall part 61) which faces the internal space of the shielding container 60 among the lower wall part 61 can reflect the infrared rays radiated | emitted downward from infrared heater unit 30a, 30b upward. Similarly, portions of the side wall portions 64a to 64d facing the inner space of the shielding container 60 can reflect infrared rays radiated from the infrared heater units 30a and 30b in the lateral direction (front and rear, left and right). As described above, in the present embodiment, the lower wall portion 61 and the side wall portions 64a to 64d shield infrared rays from the infrared heater unit 30 by reflecting infrared rays.

Further, as shown in FIG. 1, the upper wall portion 62 has a second refrigerant inlet / outlet 66. The second refrigerant is supplied from the second refrigerant supply source 54 to one of the second refrigerant inlets 66 (the right side in FIG. 1). The second refrigerant flowing into the shielding container 60 from one second refrigerant inlet / outlet 66 flows through the second flow path 67 and flows out from the other (left side in FIG. 1) second refrigerant inlet / outlet 66. . The second refrigerant flowing out from the other second refrigerant inlet / outlet 66 is discharged to the outside via the discharge valve 55. The second refrigerant is, for example, a gas such as air or an inert gas, and cools the second refrigerant by contacting the inner peripheral surface of the shielding container 60 and taking heat away when flowing through the second flow path 67. Thereby, the shielding container 60 can be maintained at a temperature lower than the ignition point of the solvent evaporating from the coating film 82 (for example, 200 ° C. or lower). Further, the second flow path 67 communicates with the hole 65, and the second refrigerant flowing through the second flow path 67 can pass through the hole 65 downward and flow out to the outside of the shielding container 60 (dry space 12a). It has become. The second refrigerant can be blown to the coating film 82 by allowing the second refrigerant to flow out of the hole 65. The flow rate of the second refrigerant from the hole 65 can be adjusted by adjusting the supply amount of the second refrigerant from the second refrigerant supply source 54 and the opening degree of the discharge valve 55. Note that penetrating portions (see FIG. 3) such as the wiring lead-out portion 44 and the first refrigerant inlet / outlet 46 in the upper wall portion 62 are sealed with a sealing material (not shown) and the like. The two refrigerants are prevented from flowing out from other than the hole 65 and the second refrigerant inlet / outlet 66.

The sheet 80 is not particularly limited, but is a metal sheet such as aluminum or copper, for example. The coating film 82 on the sheet is used as an electrode for a battery after drying, and is not particularly limited. For example, the coating film 82 becomes an electrode for a lithium ion secondary battery. As the coating film 82, for example, an electrode material paste obtained by kneading together an electrode material (positive electrode active material or negative electrode active material), a binder, a conductive material, and a solvent on the sheet 80 can be used. The thickness of the coating film 82 is not particularly limited, but is, for example, 10 to 1000 μm.

The controller 90 is configured as a microprocessor centered on a CPU. The controller 90 outputs a control signal for adjusting the magnitude of the power supplied from the power supply source 50 to the filament 32 to the power supply source 50 to individually control the filament temperature of the infrared heater unit 30. Further, the controller 90 outputs a control signal to an opening / closing valve and a flow rate adjustment valve (not shown) of the first refrigerant supply source 52 to individually control the flow rate of the first refrigerant flowing through the first flow path 47 of the infrared heater units 30a and 30b. To control. Further, the controller 90 inputs the temperature of the shielding container 60 detected by the temperature sensor 56 that is a thermocouple, outputs a control signal to an on-off valve and a flow rate adjustment valve (not shown) of the second refrigerant supply source 54, and discharges The flow rate of the second refrigerant flowing through the second flow path 67 is controlled by outputting a control signal for adjusting the opening degree of the valve 55. The controller 90 switches the conveyance and stop of the sheet 80 by switching between rotation and stop of the rolls 17 and 18, and controls the rotation speed of the rolls 17 and 18, thereby controlling the sheet 80 in the furnace body 12. In addition, the passage time of the coating film 82 and the tension applied to the sheet 80 and the coating film 82 are adjusted.

Next, how the coating film 82 is dried using the drying furnace 10 thus configured will be described. First, the coating film 82 is formed on the sheet 80 by screen printing using a coater (not shown). Then, after the coating film 82 is formed, the controller 90 rotates the rolls 17 and 18 to convey the sheet 80. As a result, the sheet 80 is unwound from the roll 17 disposed at the left end of the drying furnace 10, and the coating film 82 on the sheet 80 is carried into the furnace body 12 through the opening 15. In the present embodiment, the coating film 82 is formed and transported (positioned) so that the surface of the coating film 82 has the same size as the substantially rectangular region in which the plurality of holes 65 are formed. That is, the surface of the coated film 82 after loading is assumed to be directly below the plurality of holes 65 as shown in FIG.

When the loading of the coating film 82 is completed, the controller 90 dries the coating film 82. Specifically, the controller 90 controls the power supply source 50 to energize the filament 32 of the infrared heater units 30a and 30b to heat it. Thereby, infrared rays are emitted from the filament 32. Infrared rays from the filament 32 are reflected by the inner peripheral surface of the shielding container 60 including the reflecting surface 63 and then radiated downward from the holes 65 and are radiated to the surface of the coating film 82 to dry the coating film 82. Here, as described above, since the infrared heater units 30a and 30b have the inner tube 36 and the outer tube 40 that absorb infrared rays having a wavelength exceeding 3.5 μm, the infrared heater units 30a and 30b have a wavelength of 3 from the infrared heater unit 30a. Infrared rays of 5 μm or less are mainly emitted. Infrared rays having a wavelength of 3.5 μm or less are excellent in the ability to break hydrogen bonds in molecules such as water and solvents. Therefore, the coating film 82 can be efficiently dried.

The controller 90 controls the power supply source 50 and also controls the first refrigerant supply source 52, the second refrigerant supply source 54, and the discharge valve 55, so that the first flow path 47 and the second flow path 67 respectively. 1 refrigerant and 2nd refrigerant are circulated. Thereby, the inner pipe 36 and the outer pipe 40 are cooled by the first refrigerant flowing through the first flow path 47 and the second refrigerant flowing through the second flow path 67. Further, the shielding container 60 is cooled by the second refrigerant flowing through the second flow path 67. Further, the second refrigerant flowing through the second flow path 67 flows out from the hole 65 to the lower side of the shielding container 60 and becomes air blowing toward the coating film 82. In the present embodiment, the controller 90 controls the first refrigerant so that the flow rate of the first refrigerant becomes a flow rate determined in advance by experiments so that the inner tube 36 and the outer tube 40 do not become infrared secondary radiators. The supply source 52 was controlled. Further, the controller 90 is maintained based on the temperature of the shielding container 60 input from the temperature sensor 56 so that the shielding container 60 is maintained at a temperature lower than the ignition point of the solvent evaporating from the coating film 82 (for example, 200 ° C. or less). The second refrigerant supply source 54 and the discharge valve 55 are controlled to adjust the flow rate of the second refrigerant. The controller 90 adjusts the flow rate of the second refrigerant so that the flow rate of the second refrigerant flowing out of the holes 65 and blowing air is secured. The air blown from the holes 65 removes moisture and solvent from the inside of the coating film 82 by the action of infrared rays from the infrared heater unit 30. Thereby, the coating film 82 can be dried more efficiently. An exhaust port (not shown) is provided at the front end portion of the furnace body 12, and the atmosphere of the drying space 12a including the second refrigerant after passing over the surface of the coating film 82 is discharged from the exhaust port to the outside. Is done.

Then, after the infrared radiation from the infrared radiation device 20 to the coating film 82 is continuously performed for a predetermined time and the drying of the coating film 82 is completed, the controller 90 rotates the rolls 17 and 18 to dry the coating film 82 after drying. Is carried out of the opening 16 together with the sheet 80 to the outside of the furnace.

Thus, the drying furnace 10 includes a coating film forming process for forming the coating film 82 on the sheet 80, a loading process for transporting the sheet 80 and bringing the coating film 82 into the furnace body 12, and the furnace body 12. A drying process in which the conveyance of the sheet 80 is stopped to dry the coating film 82 and a carry-out process in which the sheet 80 is conveyed and the dried coating film 82 is unloaded are performed. Moreover, the drying furnace 10 performs simultaneously the drying process of the coating film 82, and the coating-film formation process of the following coating film 82 so that the several coating film 82 can be dried efficiently efficiently. Similarly, the carrying-out process of the coating film 82 after drying and the carrying-in process of the coating film 82 to be dried next are simultaneously performed. Since the drying furnace 10 stops the conveyance of the sheet 80 in the drying process, the coating film 82 can be accurately printed in the coating film forming process in which screen printing is performed. When the plurality of coating films 82 are continuously dried, energization of the filament 32 and cooling of the inner tube 36, the outer tube 40, and the shielding container 60 are continuously performed during the carrying-in process (carrying-out process). May be.

Here, the in-plane uniformity of the infrared radiation energy radiated downward from the hole 65 of the infrared radiation device 20 will be described. FIG. 4 is an explanatory diagram showing a state in which infrared rays are radiated from the infrared heater unit 30 alone and the infrared radiation device 20. FIG. 4A is an explanatory view showing a state in which infrared rays are radiated from a single infrared heater unit 30 shown for comparison. FIG. 4B is an explanatory diagram showing a state in which infrared rays are radiated from the infrared radiation device 20. As shown in FIG. 4A, when infrared rays are directly emitted from the infrared heater unit 30 alone to the lower coating film 82 without the shielding container 60, for example, the portion closer to the filament 32, that is, FIG. ), The portion closer to the center of the coating film 82 tends to have higher radiant energy. Therefore, the infrared radiation energy radiated to the surface of the coating film 82 (upper surface in the figure) is relatively biased within the surface. On the other hand, as shown in FIG. 4B, when infrared rays are radiated from the infrared radiation device 20 having the shielding container 60 to the coating film 82, the infrared rays directly directed to the lower side of the filament 32 are reflected by the lower wall portion 61 and reflected. Infrared light reflected by the inner peripheral surface of the shielding container 60 including 63 passes through the hole 65 and reaches the lower coating film 82. Therefore, the unevenness of the infrared radiation energy is alleviated by the infrared rays being reflected inside the shielding container 60. As a result, in the infrared radiation device 20, the in-plane uniformity of the infrared radiation energy radiated below the heating element (below the lower wall portion 61) on the surface of the coating film 82 is improved.

Here, the correspondence between the components of the present embodiment and the components of the present invention will be clarified. The filament 32 of the present embodiment corresponds to a heating element of the present invention, the lower wall portion 61 corresponds to a lower shield, the reflection surface 63 corresponds to a reflection surface, and the upper wall portion 62 corresponds to a reflector. Further, the side walls 64a to 64d correspond to side shields, the holes 65 correspond to radiation holes, the second flow channel 67 corresponds to a shielding container coolant channel and a reflector coolant channel, and the outer tube. 40 corresponds to a tubular member.

According to the infrared radiation device 20 of the drying furnace 10 of the present embodiment described above, when an electromagnetic wave including infrared rays is radiated from the filament 32, the infrared rays radiated directly from the filament 32 are moved upward by the lower wall portion 61. Is reflected and shielded. On the other hand, the infrared rays radiated upward from the filament 32 are reflected by the reflection surface 63 of the upper wall portion 62 and reach below the lower wall portion 61. In other words, the infrared light directly going directly below the filament 32 is reflected by the lower wall portion 61, and the infrared light reflected by the reflecting surface 63 reaches below. For this reason, compared with the case where the lower wall part 61 is not provided, the in-plane uniformity of infrared radiation energy radiated below the filament 32 (below the lower wall part 61) is improved. Therefore, the in-plane uniformity of infrared radiation energy to the coating film 82 arranged below the lower wall portion 61 can be improved.

Further, the lower wall portion 61 can reflect the infrared rays radiated downward from the filament 32 upward. Thereby, the infrared rays radiated downward from the filament 32 are reflected by the lower wall portion 61 and further reflected by the reflecting surface 63 of the upper wall portion 62 so as to reach the lower portion of the lower wall portion 61. Therefore, for example, compared with the case where the lower wall portion 61 absorbs infrared rays without reflecting the infrared rays, the infrared rays from the filament 32 can be efficiently emitted to the coating film 82.

Furthermore, since the shielding container 60 includes the second flow path 67 through which the second refrigerant can be circulated, it is possible to suppress overheating due to the upper wall portion 62 absorbing a part of infrared rays.

The infrared radiation device 20 includes side wall portions 64a to 64d that shield infrared rays emitted from the filament 32 in the front-rear and left-right directions perpendicular to the lower direction. Therefore, it is possible to further suppress the infrared rays radiated from the filament 32 from directly reaching the coating film 82 without reflection. Thereby, the in-plane uniformity of the infrared radiation energy to the coating film 82 can be further improved.

Further, the infrared radiation device 20 includes an upper wall portion 62, a lower wall portion 61, and side wall portions 64a to 64d, and includes a shielding container 60 that covers the filament 32. The shielding container 60 includes the filament 32. It has a hole 65 that is an infrared ray exit from the shielding container 60 when infrared rays formed at positions other than directly below and reflected by the reflecting surface 63 reach below the lower wall portion 61. Thereby, the in-plane uniformity of the infrared radiation energy to the coating film 82 arrange | positioned under the hole 65 can be improved. Moreover, since the filament 32 is covered with the shielding container 60, it is possible to further suppress the infrared rays radiated from the filament 32 from directly reaching the coating film 82 without reflection. Further, the hole 65 has a shape and an arrangement such that infrared rays emitted from the filaments 32 of the infrared heater units 30a and 30b cannot pass through the hole 65 without being reflected. As a result, the infrared rays from the filament 32 pass through the holes 65 without reflection and directly reach the object to be processed, and the in-plane uniformity of the infrared radiation energy emitted to the object to be processed is reduced. It can be improved further.

Moreover, the lower wall portion 61 and the side wall portions 64a to 64d can reflect infrared rays from the filament 32 on the surface on the filament 32 side. Thereby, at least a part of the infrared rays radiated from the filament 32 is radiated from the hole 65 after being reflected a plurality of times in the shielding container 60. Therefore, the in-plane uniformity of the infrared radiation energy radiated from the hole 65 to the coating film 82 can be further improved. Moreover, since all the inner peripheral surfaces except the hole 65 of the shielding container 60 can reflect infrared rays, the infrared rays from the filament 32 can be radiated to the coating film 82 more efficiently.

Furthermore, the infrared radiation device 20 includes a second flow path 67 through which a second refrigerant for cooling the shielding container 60 can flow. Thereby, the overheating of the shielding container 60 due to the irradiation with infrared rays can be further suppressed by the second refrigerant. The hole 65 is an opening communicating with the outside of the shielding container 60 and the second flow path 67. Thereby, the shielding container 60 can be cooled by the second refrigerant, and the second refrigerant can flow out from the hole 65 downward. Therefore, by circulating gas as the second refrigerant, the second refrigerant can serve both for cooling the shielding container 60 and blowing air to the coating film 82.

Furthermore, a plurality of infrared heater units 30 (filaments 32) are arranged in the shielding container 60 and arranged on both sides of the hole 65 in the left-right direction perpendicular to the up-down direction. Thereby, since infrared rays can be emitted from the plurality of filaments 32, the infrared radiation intensity from the holes 65 can be increased. Moreover, since the filaments 32 are arranged on both sides of the hole 65 in the left-right direction, for example, the in-plane uniformity of the infrared radiation energy from the hole 65 is further improved as compared with the case where the heating element is provided only on one of the left and right sides. be able to.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

For example, in the above-described embodiment, the reflection surface 63 is a surface that reflects infrared rays, but the reflection surface 63 is not limited to a regular reflection (specular reflection) of infrared rays, and may be a surface that irregularly reflects infrared rays. If the reflecting surface 63 is a surface capable of irregularly reflecting infrared rays, the in-plane uniformity of infrared radiation energy to the coating film 82 can be further improved. In addition, since infrared rays can be irregularly reflected more reliably, the reflective surface 63 may have an arithmetic average roughness Ra equal to or greater than the wavelength of infrared rays. For example, the reflective surface 63 may have an arithmetic average roughness Ra of 3.5 μm or more, which is the maximum value of the wavelength of near infrared rays (wavelength 0.7 μm to 3.5 μm).

In the above-described embodiment, the hole 65 formed in the lower wall portion 61 is an infrared radiation outlet, but is not limited thereto. For example, the infrared radiation device 20 may include a waveguide that guides infrared rays from the filament 32 to the radiation port. FIG. 5 is a vertical cross-sectional view of a drying furnace 110 provided with a modified infrared radiation device 120. The drying furnace 110 is the same as the drying furnace except that the infrared radiation device 120 includes a waveguide 168 unlike the infrared radiation device 20, and the hole 165 is formed in the lower wall portion 61 instead of the hole 65. 10 is the same configuration. Therefore, the same components as those in the drying furnace 10 among the components in the drying furnace 110 are denoted by the same reference numerals as those in the drying furnace 10 and the description thereof is omitted. In the drying furnace 110, a plurality of holes 165 are formed in the lower wall portion 61 near the middle in the left-right direction between the infrared heater unit 30a and the infrared heater unit 30b. Although not shown in detail, the holes 165 are formed by arranging a total of 15 holes in three rows in the left-right direction and five rows in the front-rear direction in a substantially rectangular shape. A waveguide 168 is connected to each of the plurality of holes 165. The waveguide 168 has an inner peripheral surface along the vertical direction, the upper end opening is connected to the hole 165, and the lower end opening 169 is an infrared radiation outlet. The waveguide 168 plays a role of guiding the infrared light to the opening 169 by reflecting the infrared light reflected by the reflecting surface 63 on the inner peripheral surface. In the drying furnace 110 of this modification, at least a part of the infrared rays emitted from the filament 32 is reflected by the inner peripheral surface of the waveguide 168 and then emitted from the opening 169 to reach the coating film 82. For this reason, infrared rays are reflected not only inside the shielding container 60 but also inside the waveguide 168, so that infrared rays radiated from the opening 169 to the coating film 82 below (particularly, infrared rays radiated directly below the opening 169). The in-plane uniformity of the radiant energy is further improved. The inner peripheral surface of the waveguide 168 is preferably capable of totally reflecting infrared rays. If it carries out like this, infrared rays can be radiated | emitted to the coating film 82 more efficiently. The inner peripheral surface of the waveguide 168 may be capable of totally reflecting infrared rays having a wavelength of 3.5 μm or less. Further, like the hole 65 of the above-described embodiment, the waveguide 168 preferably has a shape and an arrangement such that infrared rays radiated from the filament 32 cannot reach the opening 169 without being reflected. . In addition, since the waveguide 168 can easily lengthen the infrared path in the vertical direction as compared with the hole 65, the waveguide 168 can be easily configured so that the infrared rays cannot reach the opening 169 without being reflected.

In the embodiment described above, a plurality of holes 65 are formed, but the number of holes 65 may be one or more. However, the formation of a plurality of holes 65 facilitates a configuration in which the infrared radiation from the filament 32 cannot pass through the holes 65 without reflection, while increasing the total area of the infrared radiation outlet. Similarly, the number of the holes 165 and the waveguides 168 shown in FIG.

In the above-described embodiment, the hole 65 is an opening, but may be an infrared ray outlet from the shielding container 60. That is, the hole 65 only needs to be able to transmit infrared rays. For example, as shown in FIG. 6, a partition member 65 a that transmits infrared rays and partitions the inside and outside of the shielding container 60 may be provided inside the hole 65. In this case, the air cannot be blown from the hole 65 to the coating film 82, but the infrared light can be radiated from the hole 65 to the coating film 82 by passing through the partition member 65 a. The partition member 65a may be formed of an infrared absorbing material that transmits infrared rays having a wavelength of 3.5 μm or less and absorbs infrared rays having a wavelength exceeding 3.5 μm. In this way, even if the inner tube 36 and the outer tube 40 are not formed of an infrared absorbing material, infrared rays having a wavelength of 3.5 μm or less can be selectively emitted to the coating film 82 and can be efficiently dried. . In this case, the inner tube 36 and the outer tube 40 may not be provided.

In the above-described embodiment, two infrared heater units 30 are arranged in the shielding container 60, but may be one, or may be three or more. FIG. 7 is a perspective view of a modified infrared radiation device 220. As shown in FIG. 7, the infrared radiation device 220 according to the modified example includes infrared heater units 30c and 30d whose longitudinal direction is the left-right direction in addition to the infrared heater units 30a and 30b. That is, the infrared radiation device 220 has a total of four infrared heater units 30. The configuration of the infrared heater units 30c and 30d is the same as that of the infrared heater units 30a and 30b. The infrared heater units 30a to 30d are disposed in the vicinity of the side wall portions 64a to 64d in the shielding container 60, respectively. The infrared heater units 30a to 30d are respectively disposed between the side walls 64a to 64d in the shielding container 60 and the hole 65, and are positioned so as to surround the hole 65 from the front, rear, right and left. Thereby, since the filament 32 of the infrared heater units 30a to 30d is disposed so as to surround the hole 65, the in-plane uniformity of the infrared radiation energy from the hole 65 can be further improved. Further, by increasing the number of infrared heater units 30, the infrared radiation intensity from the holes 65 can be increased. Moreover, you may increase the infrared heater unit 30 further from the infrared radiation apparatus 220 of a modification. FIG. 8 is a perspective view of a modified infrared radiation device 320. In addition to the infrared heater units 30a to 30d, the infrared radiation device 320 of the modified example is an infrared heater located in the middle between the infrared heater unit 30a and the infrared heater unit 30b in the longitudinal direction in addition to the infrared heater units 30a to 30d. It has a unit 30e. That is, the infrared radiation device 320 has a total of five infrared heater units 30. The configuration of the infrared heater unit 30e is the same as that of the infrared heater units 30a to 30d. In addition, a plurality of holes 365a and 365b are formed in place of the holes 65 at positions other than directly below the infrared heater units 30a to 30e in the lower wall portion 61. A plurality of holes 365a are formed near the middle in the left-right direction between the infrared heater unit 30a and the infrared heater unit 30e, and are surrounded by the infrared heater units 30a, 30c, 30d, and 30e. A plurality of holes 365b are formed near the middle in the left-right direction between the infrared heater unit 30b and the infrared heater unit 30e, and are surrounded by the infrared heater units 30b, 30c, 30d, and 30e. Thus, by further increasing the number of infrared heater units 30, the infrared radiation intensity from the holes 365a and 365b can be further increased.

In the above-described embodiment, the inner peripheral surface of the shielding container 60 is capable of reflecting infrared rays, but it is sufficient that at least the reflection surface 63 and the lower wall portion 61 can reflect infrared rays. The side wall portions 64a to 64d only need to be able to shield infrared rays from the filament 32, and may be, for example, those that absorb infrared rays without reflecting them.

In the above-described embodiment, the upper wall portion 62 is formed of an infrared reflecting material that reflects infrared rays, but it is sufficient that the reflecting surface 63 can reflect infrared rays. For example, an infrared reflection layer capable of reflecting infrared rays is formed on the surface of the upper wall portion 62, and the surface of the infrared reflection layer may be used as the reflection surface 63. Examples of the material used for such an infrared reflective layer include gold, platinum, and aluminum. The infrared reflective layer can be formed, for example, by forming an infrared reflective material on the surface of the upper wall portion 62 using a film forming method such as coating and drying, sputtering, CVD, or thermal spraying. Note that the lower wall portion 61 and the side wall portions 64a to 64d may also be configured to be able to reflect infrared rays by forming an infrared reflecting layer in a portion facing the internal space of the shielding container 60.

In the above-described embodiment, the internal space in which the infrared heater unit 30 is disposed in the shielding container 60 is the second flow path 67. For example, each of the lower wall portion 61, the upper wall portion 62, and the side wall portions 64a to 64d. In addition to the internal space in which the infrared heater unit 30 is disposed, a second flow path capable of circulating the second refrigerant may be formed. Even in this case, the shielding container 60 can be cooled by the second refrigerant.

In the above-described embodiment, the space between the inner tube 36 and the outer tube 40 is the first flow path 47, but the first refrigerant may not be circulated between the inner tube 36 and the outer tube 40. Even in this case, the outer pipe 40 can be cooled by circulating the second refrigerant between the shielding container 60 and the outer pipe 40. In this case, one of the inner tube 36 and the outer tube 40 may be omitted.

In the above-described embodiment, the infrared heater unit 30 is covered with the shielding container 60. However, the lower wall portion 61 that shields infrared rays emitted from the filament 32 and the filament 32 is emitted upward. If it has the upper wall part 62 which reflects infrared rays, it will not be restricted to this. For example, the side walls 64a to 64d may not be provided. Alternatively, the lower wall portion 61, the upper wall portion 62, and the side wall portions 64a to 64d are separated from each other. For example, the lower wall portion 61, the upper wall portion 62, and the side wall portions 64a to 64d are not joined to each other. It may be arranged around the unit 30.

In the above-described embodiment, the lower wall portion 61 and the upper wall portion 62 exist around the infrared heater unit 30, but the present invention is not limited to this. For example, instead of the lower wall portion 61, a layered shielding body that shields infrared rays from the filament 32 may be formed on the surface of the outer tube 40. FIG. 9 is a longitudinal sectional view of a drying furnace 410 provided with a modified infrared radiation device 420. As illustrated, the infrared radiation device 420 does not include the shielding container 60 but includes an infrared heater unit 430 and a reflection plate 462 that is a plate-like member that covers the infrared heater unit 30. The infrared heater unit 430 has the same configuration as the infrared heater unit 30 except that the infrared heater unit 430 has a layered shield 461 formed on the outer surface of the outer tube 40 (see the enlarged portion in FIG. 9). The shield 461 has the same longitudinal direction as that of the outer tube 40 and shields infrared rays radiated directly from the filament 32 by reflection like the lower wall portion 61. The shield 461 is made of an infrared reflecting material, and is configured as the above-described infrared reflecting layer capable of reflecting the infrared rays from the filament 32 upward. The shield 461 covers the lower side of the surface of the outer tube 40. In FIG. 9, the downward direction is 0 ° as viewed from the filament 32, and the surface of the outer tube 40 is −45 ° to the left and right in the cross-sectional view. It covers a range of 45 ° (the counterclockwise direction in FIG. 9 is positive). However, the shield 461 only needs to reflect the infrared rays radiated from the filament 32 directly below. For example, the shield 461 may cover at least the region directly below the filament 32 (the width in the left-right direction is wider than that of the filament 32). The shield 461 may cover a range of −90 ° to 90 °, for example, or may cover another range. Depending on the size of the coating film 82 in the drying process and the positional relationship with the filament 32, the shield 461 is disposed on the outer tube 40 so that infrared rays radiated from the filament 32 cannot reach the coating film 82 without reflection. You may define the range which covers the surface of. The reflection plate 462 is disposed outside the outer tube 40 when viewed from the filament 32. The reflection plate 462 has the same longitudinal direction as that of the infrared heater unit 30, and the cross-sectional shape of the reflection surface 463 that is the surface on the filament 32 side is a curved shape such as a parabola, an elliptical arc, or an arc. The filament 32 may be disposed at the focal point or the center position of the reflecting surface 463 in the curved shape. The reflecting plate 462 can reflect infrared rays downward on the reflecting surface 463. The reflecting plate 462 may be formed of an infrared reflecting material, similar to the upper wall portion 62 described above. Further, an infrared reflection layer capable of reflecting infrared rays is formed on the surface of the reflection plate 462 on the filament 32 side, and the surface of the infrared reflection layer may be a reflection surface 463. The reflection plate 462 preferably covers a region directly above the shield 461 (wider in the left-right direction than the shield 461). Similarly to the infrared radiation device 20 described above, the infrared radiation device 420 is also shielded by being reflected by the shield 461 with respect to the infrared radiation radiated directly from the filament 32. On the other hand, infrared rays radiated upward from the filament 32 are reflected by the reflecting surface 463 and reach below the shield 461. Thereby, in the same manner as the infrared radiation device 20, the in-plane uniformity of the infrared radiation energy to the coating film 82 disposed below the infrared heater unit 30 (for example, directly below the filament 32 or directly below the reflecting surface 463). Can be improved. The shield 461 may be formed on the inner peripheral surface of the outer tube 40, or may be formed on the outer peripheral surface or inner peripheral surface of the inner tube 36. Further, the reflection plate 462 may be flat. That is, the cross section of the reflecting surface 463 may be a straight shape instead of a curved shape. Further, the reflection surface 463 may be capable of irregularly reflecting infrared rays. Further, the infrared radiation device 420 may include a reflector coolant channel through which a coolant for cooling the reflector 462 can flow. For example, a pipe that contacts the surface of the reflector 462 opposite to the filament 32 (upper surface in FIG. 9) is provided, and the refrigerant is circulated through the pipe using the internal space of the pipe as a refrigerant flow path for the reflector. Also good. Alternatively, a coolant channel may be formed inside the reflecting plate 462, and the coolant may be circulated inside the reflecting plate 462.

In FIG. 9, the infrared radiation device 420 including the shielding body 461 without the shielding container 60 has been described. However, the infrared radiation device may include both the shielding container 60 and the shielding body 461. FIG. 10 is a longitudinal sectional view of a drying furnace 510 provided with a modified infrared radiation device 520. In the infrared radiation device 520 of the drying furnace 510, a layered shield 537 is formed on the outer surface of the outer tube 40 of the infrared heater unit 30. The shield 537 is configured as the above-described infrared reflecting layer capable of reflecting the infrared rays from the filament 32 upward, similarly to the shield 461 shown in FIG. Also, a plurality of holes 565 formed in the lower wall portion 561 are formed in the entire lower wall portion 561 including the region directly below the infrared heater unit 30 unlike the hole 65 of FIG. In the drying furnace 510, as in the drying furnace 10, the infrared rays emitted directly below the filament 32 are reflected and shielded upward by the shield 537. On the other hand, infrared rays radiated upward from the filament 32 are reflected by the reflecting surface 63 of the upper wall portion 62, pass through the hole 565, and reach below the lower wall portion 561. Therefore, the in-plane uniformity of infrared radiation energy radiated below the filament 32 (below the lower wall portion 561) is improved. Moreover, since the hole 565 can be formed also in the region directly under the infrared heater unit 30 by having the shield 537, it is also in-plane with respect to the processing target disposed in the region directly under the infrared heater unit 30. Infrared rays can be emitted while maintaining uniformity. That is, a region where infrared rays can be emitted while maintaining in-plane uniformity extends in the left-right direction of the figure. Thereby, the surface area of the coating film 82 which can be dried at once in the furnace body 12 can be increased, and the processing efficiency is improved. In addition, since the shielding body 537 shields the infrared rays radiated directly from the filament 32 by the reflection, the lower wall portion 561 is not necessarily made of a material that reflects the infrared rays. For example, the lower wall portion 551 may be made of a material that absorbs infrared rays or a material that transmits infrared rays. Further, when the lower wall portion 561 transmits infrared rays, the hole 565 may not be formed.

In the above-described embodiment, the drying furnace 10 may further include a blower that blows air toward the surface of the coating film 82 or in parallel with the surface of the coating film 82.

In the embodiment described above, the vertical downward direction has been described as “downward”, but it is only necessary to define the upward direction and the left-right direction with reference to “downward direction”, and even if “downward direction” is another direction. Good. For example, the vertically upward direction may be “downward”. In that case, the infrared radiation device 20 radiates infrared rays to a processing object arranged vertically upward.

In the embodiment described above, the drying furnace 10 is an intermittent feed type, but is not limited thereto. For example, you may comprise as a continuous-type drying furnace which dries the coating film 82, conveying the sheet | seat 80 inside the furnace body 12 continuously. Or you may comprise as a batch-type drying furnace which does not equip the rolls 17 and 18 and mounts the sheet | seat 80 in which the coating film 82 was formed in the furnace body 12, and dries.

In the above-described embodiment, the coating film 82 to be processed is exemplified by a coating film that becomes an electrode for a lithium ion secondary battery after drying, but the drying symmetry is not limited thereto. For example, a coating film used as a thin film for MLCC (multilayer ceramic capacitor) may be a processing target. In this case, the coating film may contain, for example, ceramic powder or metal powder, an organic binder, and an organic solvent. The sheet may be a resin such as PET. Alternatively, the coating film 82 may be used as a thin film for LTCC (low temperature fired ceramics) or other green sheets. In the present embodiment, the coating film 82 is formed on the sheet 80 by screen printing. However, the present invention is not limited thereto, and the coating film 82 may be formed using other methods such as gravure printing.

In the above-described embodiment, the drying furnace 10 dries the coating film 82 using infrared rays. However, the drying oven 10 is not limited to a drying oven as long as it is an infrared treatment apparatus that treats a treatment target using infrared rays. Examples of the treatment using infrared rays include chemical reactions such as cross-linking and imidization of the treatment target, dehydration, annealing, and the like.

This application is based on Japanese Patent Application No. 2013-167482, filed on August 12, 2013, and claims the priority thereof, the entire contents of which are incorporated herein by reference.

INDUSTRIAL APPLICABILITY The present invention can be used in industries that require treatment such as drying using infrared rays on the object to be treated, such as the battery industry that produces electrode coatings for lithium ion secondary batteries, and the ceramic industry that produces MLCC or LTCC. It is.

10 drying furnace, 12 furnace body, 12a drying space, 13 left end face, 14 right end face, 15, 16 opening, 17, 18 roll, 20 infrared radiation device, 30, 30a-30e infrared heater unit, 32 filament, 34 electrical wiring , 36 inner pipe, 38 heater body, 40 outer pipe, 42 cap, 44 wiring outlet, 46 first refrigerant inlet / outlet, 47 first flow path, 49 holder, 50 power supply source, 52 first refrigerant supply source, 54th 2 refrigerant supply source, 55 discharge valve, 56 temperature sensor, 60 shielding container, 61 lower wall part, 62 upper wall part, 63 reflecting surface, 64a-64d side wall part, 65 holes, 65a partition member, 66 second refrigerant inlet / outlet, 67 2nd flow path, 80 sheet, 82 coating film, 90 controller, 110 drying furnace, 120 External radiation device, 165 hole, 168 waveguide, 169 opening, 220, 320 infrared radiation device, 365a, 365b hole, 410 drying furnace, 420 infrared radiation device, 430 infrared heater unit, 461 shield, 462 reflector, 463 Reflective surface, 510 drying furnace, 520 infrared radiation device, 537 shield, 561 lower wall, 565 hole.

Claims (14)

1. A heating element that emits electromagnetic waves including infrared when heated,
   A lower shield that reflects upward the infrared rays emitted directly from the heating element when the predetermined direction is a downward direction;
   A reflector having a reflecting surface for reflecting infrared rays radiated upward from the heating element so that the infrared rays can reach below the lower shield;
   Infrared radiation device with.
2. The reflective surface is a surface that irregularly reflects the infrared rays,
   The infrared radiation device according to claim 1.
3. The infrared radiation device according to claim 1 or 2,
   A side shield that shields infrared rays emitted from the heating element in a direction perpendicular to the downward direction;
   Infrared radiation device with.
4. The infrared radiation device according to claim 3,
   A shielding container having the reflector, the lower shielding body, and the side shielding body and covering the heating element;
   With
   The shielding container is a radiation port that is formed at a position other than directly below the heating element and serves as an outlet for the infrared light from the shielding container when the infrared light reflected by the reflecting surface reaches below the lower shielding body Having
   Infrared radiation device.
5. The lower shielding body and the side shielding body are capable of reflecting infrared rays from the heating element on the surface on the heating element side.
   The infrared radiation device according to claim 4.
6. An infrared radiation device according to claim 4 or 5,
   A refrigerant flow path for a shielding container through which a refrigerant for cooling the shielding container can flow;
   Infrared radiation device with.
7. The infrared radiation device according to claim 6,
   A tubular member disposed inside the shielding container and transmitting infrared rays from the heating element to cover the heating element;
   With
   The shielding container coolant channel is a space between the shielding container and the tubular member.
   Infrared radiation device.
8. The radiation port is an opening communicating with the outside of the shielding container and the refrigerant flow path for the shielding container.
   The infrared radiation device according to claim 6 or 7.
9. The shielding container includes a partition member that transmits infrared rays and blocks the radiation port to partition the inside and outside of the shielding container.
   The infrared radiation device according to any one of claims 4 to 7.
10. The infrared radiation device according to any one of claims 4 to 9,
    A waveguide having an inner peripheral surface along the vertical direction, and guiding the infrared light to the radiation port by reflecting the infrared light reflected by the reflecting surface by the inner peripheral surface;
    Infrared radiation device with.
11. A plurality of the heating elements are arranged in the shielding container, and arranged on both sides of the radiation port in a direction perpendicular to the vertical direction.
    The infrared radiation device according to any one of claims 4 to 10.
12. The shielding container is a rectangular parallelepiped container having an upper wall portion including the reflector, a lower wall portion including the lower shielding body, and four side wall portions including the side shielding body,
    A plurality of the heating elements are arranged in the shielding container, and are arranged between the four side wall portions in the shielding container and the radiation port, respectively, so that the radiation ports are arranged in a direction perpendicular to the vertical direction. It is located to surround the surroundings,
    The infrared radiation device according to claim 11.
13. The infrared radiation device according to any one of claims 1 to 3,
    A tubular member that transmits infrared rays from the heating element and covers the heating element;
    With
    The lower shield is formed on the inner peripheral surface or the outer peripheral surface of the tubular member,
    Infrared radiation device.
14. An infrared processing apparatus comprising the infrared radiation device according to any one of claims 1 to 13, wherein the infrared radiation device radiates infrared rays to a processing target positioned below the infrared radiation device.

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