Hot air drying device

Abstract

To provide a hot air type dryer excellent in environment friendliness, energy efficiency and safety, capable of adopting a heater heating system and suppressing heating energy required for obtaining a proper temperature and amount of heating hot air generated by heater heating due to its configuration of circulating and mixing exhaust hot air.SOLUTION: The hot air type dryer comprises a hot air generator 5 configured to control mixed hot air at an intended temperature, the mixed hot air being prepared by mixing heater heated hot air generated by heating sucked air by a heater 6 with exhaust hot air circulated from a drying chamber 3, to deliver it to a hot air delivery unit 4 present in the drying chamber 3.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a drying device provided in a coating device configured to convey a film-shaped workpiece (base material) and form a thin film (coating film) on the surface by discharging a coating liquid from, for example, a slit-shaped tip discharge hole. The drying device is a hot air drying device configured to convey a film-shaped base material after coating through a drying chamber configured to heat with hot air to dry the coating film on the surface of the base material.

Background Art

[0002] A hot air drying device provided in a coating device conveys a film-shaped base material on which a coating liquid is coated on the surface by the coating device and sent out from the coating device, and dries the coating film on the surface of the base material by hot air or heat from a further provided heater unit.

[0003] Such a hot air drying device is configured to include a plurality of drying chambers arranged side by side on the left and right with a main body part (a divided drying chamber forming part) for conveying a film-shaped base material through conveyance inlet / outlet parts provided on the left and right, and to form a long drying chamber length. In each drying chamber forming part constituting the drying chamber part, for example, a large number of support rollers are arranged side by side in the horizontal direction, the film-shaped base material is passed through the support rollers, and while the film-shaped base material is pulled and horizontally conveyed, the coating surface (coating film) of the base material is dried by hot air from a hot air delivery part or heat from a further provided heater unit, or hot air delivery parts are provided above and below to dry the coating film in a floating drying method while conveying it non-contact.

[0004] Also, such a hot air drying device is configured to include a hot air generation part that sends hot air heated and generated to a desired temperature into the hot air delivery part provided in the drying chamber part.

[0005] If this hot air generating unit is simply configured to draw in the air (outside air) drawn in by the air blowing unit (suction fan), heat it with the heater unit to generate hot air, and blow and send this hot air to the hot air sending unit through a conduit, it would require a large amount of heating energy and be inefficient. Therefore, all or part of the exhaust hot air from the drying chamber unit is branched off from the exhaust pipe and circulated, reheated, or mixed with the drawn-in outside air, heated to generate hot air at a desired temperature, and then sent back to the hot air sending unit of the drying chamber unit again.

[0006] Also, depending on the coating liquid applied to this substrate, there is a risk of generating dangerous gases such as flammable gases during drying. Therefore, there is a risk that the exhaust hot air contains such dangerous gases at a concentration above the dangerous level. For this reason, it is not preferable to heat the exhaust hot air exhausted from the drying chamber unit or the mixed hot air of this exhaust hot air and outside air with a heater in the heater unit for heating.

[0007] Therefore, conventionally, the heat source of the hot air generating unit for heating the circulated exhaust hot air is, for example, a steam type heat exchanger in which steam heated by a boiler is passed through a heat exchange pipe, and the exhaust hot air is sent through this to perform heat exchange heating.

[0008] However, in recent years, the demand for CO2 reduction to prevent global warming has been increasing, and there is an increasing demand to change the configuration of the hot air of the drying device to heater heating by an electric heater unit instead of heat exchange heating by a steam type heat exchanger that requires boiler heating.

[0009] Therefore, the applicant has been engaged in the research and development of a drying device that satisfies this demand while solving these problems, and the inventor has created the present invention.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0011] The present invention solves such problems and meets such requirements. Since the hot air of a desired temperature sent into the hot air discharge part of the drying chamber part is generated by heating with an electric heater part, it can respond to the demand for CO2 reduction and realize an environmentally friendly drying device. Moreover, since the drawn-in air is mixed with the heater-heated hot air obtained by heating the air with the heater and the exhaust hot air circulated, and the hot air of the desired temperature is generated by mixing, the energy efficiency can be improved, power can be saved, and it is more environmentally friendly. Further, even in the case of a drying device for drying a coating film which may generate dangerous gases such as combustible gas during drying, since the air (outside air) drawn in is heated by the heater without heating the exhaust hot air containing this, it aims to provide a hot air type drying device equipped with a hot air generation part excellent in safety.

Means for Solving the Problems

[0012] The gist of the present invention will be described with reference to the accompanying drawings.

[0013] The present invention is a hot air type drying device in which a hot air sending part 4 for sending hot air for drying the coating liquid applied to a film-shaped base material 2 conveyed through a drying chamber part 3 where the coating liquid is applied by a coating device 1 and sent out from the coating device 1 is provided. A hot air generation part 5 for generating hot air to be sent into the hot air sending part 4 of the drying chamber part 3 is provided. The hot air generation part 5 for sending hot air into the hot air sending part 4 on at least the upstream side of the conveyance of the base material 2 in the drying chamber part 3 draws in air Electric type and heats it with a heater part 6 to generate a heater-heated generation part 7 for generating hot air, and a mixing part 8 for mixing the heater-heated hot air generated by the heater-heated generation part 7 and the exhaust hot air exhausted from the drying chamber part 3 and sending out the mixed hot air, and a blower part 9. and does not heat the exhaust hot airconfigured such that the mixed hot air drawn in and mixed by the air blowing unit 9 is sent to the hot air delivery unit 4 of the drying chamber unit 3 sent to the hot air delivery unit 4 The heating degree of the heater unit 6 is controlled according to the mixing ratio of the heater-heated hot air and the exhaust hot air so that the temperature of the hot air becomes the desired temperature as It is configured to include a hot air temperature control unit C that controls and The drying chamber unit 3 is configured such that a plurality of drying chamber forming units 11 are arranged side by side and connected in the conveying direction of the base material 2 The downstream hot air generation unit 12 that generates hot air and sends it to the hot air delivery unit 4 provided in the drying chamber forming unit 11 on the conveyance downstream side, which is provided in the drying chamber forming unit 11 on the conveyance upstream side of the base material 2 and sends hot air to the hot air delivery unit 4 on the conveyance upstream side, is different from the hot air generation unit 5 on the conveyance upstream side. It is composed of a circulation mixing heater heating generation unit 13 that heats the mixed hot air in which the drawn-in air and the exhaust hot air exhausted from the drying chamber unit 3 are mixed by the electric heater unit 6 to generate heater-heated mixed hot air, and the blower unit 9. The heater-heated mixed hot air generated by this circulation mixing heater heating generation unit 13 is configured to be sent to the hot air delivery unit 4 provided in the drying chamber forming unit 11 on the conveyance downstream side It relates to a hot air drying device characterized by this

[0014] Also On the conveyance upstream side of the base material 2 The hot air generation unit 5 draws in and mixes the heater-heated hot air generated by the heater heating generation unit 7 and the exhaust hot air exhausted from the drying chamber unit 3 by a blowing negative pressure, and the air blowing unit 9 is provided at a position where the drawn and mixed mixed hot air is blown and sent to the hot air delivery unit 4 of the drying chamber unit 3. The exhaust hot air is not heated by the heater unit 6 of the heater heating generation unit 7. It relates to the hot air drying device according to claim 1, characterized by this

[0015] Also, a temperature sensor 10 for detecting the temperature of the mixed hot air sent to the hot air delivery unit 4 of the drying chamber unit 3 is provided, and the hot air temperature control unit C is configured to control the heating intensity of the heater unit 6 based on the temperature detected by this temperature sensor 10. It relates to the drying device according to claim 1, characterized by this

[0016]

[0017] Also, a gas sensor 14 for detecting the degree to which the exhaust hot air contains combustible gas is provided 1 It relates to the hot air drying device described

Effects of the Invention

[0018] Since the present invention is configured as described above, the hot air at the desired temperature sent to the hot air discharge part of the drying chamber is generated by heating with an electric heater part, so it can meet the demand for CO2 reduction and realize an environmentally friendly drying device. At the same time, since the drawn-in air is mixed with the heater-heated hot air heated by the heater and the exhaust hot air circulated to generate the hot air at the desired temperature, the energy efficiency can be improved and power can be saved, making it more environmentally friendly. Moreover, even for a drying device that dries a coating film that may generate dangerous gases such as flammable gases during drying, since the air (outside air) taken in is heated by the heater without heating the exhaust hot air contained therein, it becomes a hot air drying device equipped with a hot air generation part excellent in safety.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0020] The embodiments of the present invention considered to be suitable will be briefly described with reference to the drawings to show the operation of the present invention.

[0021] For example, the film-shaped base material 2 coated by the coating device 1 is dried by passing through the drying chamber part 3, and the coating film formed on the surface is dried.

[0022] That is, for example, the base material 2 coated on the upper surface is taken in and conveyed through the drying chamber part 3, and the coating film on the upper surface is dried by the heat of the hot air sent out from the hot air delivery part 4 provided in the drying chamber part 3.

[0023] The hot air sent into the drying chamber 3 from the hot air outlet 4 is heated and generated by the hot air generation unit 5, and is sent into the drying chamber 3 through the hot air outlet 4 by the air blowing unit 9 (a blower device or a fan device).

[0024] In the present invention, for example, outside air is drawn into the heater heating generation unit 7 of the hot air generation unit 5 by the air blowing unit 9 such as an intake fan, and this outside air is heater-heated by the electric heater unit 6 of the heater heating generation unit 7. The heater-heated hot air and the exhaust hot air (all or part of the exhaust hot air) exhausted from the drying chamber 3 are drawn into the mixing unit 8 at a predetermined mixing ratio through the valve 21, merged and mixed, and further, this mixed hot air is blown and sent out to the hot air outlet 4, and is sent into the drying chamber 3 through the hot air outlet 4.

[0025] Therefore, in the present invention, since the heating source (the heating source of the hot air generation unit 5) for obtaining the hot air of the desired temperature and the desired amount sent into the hot air outlet 4 of the drying chamber 3 is configured to be heater-heated by the electric heater unit 6 without using a steam heat exchanger that requires boiler heating, it is possible to meet the demand for CO2 reduction and realize an environmentally friendly drying device.

[0026] In addition, since the configuration is such that the heated hot air obtained by heater-heating the drawn-in air and the exhaust hot air to be circulated are drawn in, merged, and mixed, the temperature and the amount of the heated hot air can be reduced, the energy efficiency can be improved, power can be saved, and the hot air generation unit 5 becomes more environmentally friendly.

[0027] Moreover, even when drying a coating film that may generate dangerous gases such as combustible gas during drying in this exhaust hot air that is mixed to enhance efficiency, since the hot air generation unit 5 is configured to heater-heat the drawn-in outside air without heating this exhaust hot air, it is excellent in safety and also becomes a hot air generation unit 5 that can adopt the heater heating method.

[0028] For example, the electrode film of a lithium-ion battery is formed by applying an electrode film onto the upper surface of a base material 2 such as aluminum or copper foil and then drying it. When drying this electrode film, there is a possibility that flammable dangerous gases may be generated when the binder (a substance that adheres the electrode film to the base material) in the electrode film dries. A gas sensor is provided to monitor this to ensure that this concentration does not reach a dangerous level, and based on this monitoring, the amount of exhaust hot air to be circulated must be suppressed. Conventionally, a steam type heat exchanger using boiler heating was adopted without using heater heating. However, in the present invention, since the configuration is such that the exhaust hot air is not heated even when drying such a coating film, a heater heating method can be adopted. Therefore, a large amount of exhaust hot air can be circulated and mixed, and furthermore, the heating energy for obtaining the temperature and amount of the heated hot air by heater heating to be mixed into this exhaust hot air can be suppressed, enabling the realization of a hot air drying apparatus equipped with an epoch-making hot air generation unit that is excellent in environmental performance, energy efficiency, and safety.

Example

[0029] Specific embodiments of the present invention will be described with reference to the drawings.

[0030] In this embodiment, a film-shaped workpiece to be coated (base material 2) drawn from a winding roll 15 is drawn and conveyed through an opposing support roller 17 facing the nozzle portion 16 of a coating apparatus 1. A coating liquid is discharged from the tip discharge hole of this nozzle portion 16, and after coating this coating liquid on one side (upper surface) of the film-shaped base material 2 supported by this opposing support roller 17, the coated film-shaped base material 2 is horizontally conveyed through the drying chamber portion 3 of the drying apparatus and dried, and then wound around a recovery roll 18. The present invention is applied to the drying apparatus provided in the coating apparatus 1.

[0031] That is, this drying apparatus of this embodiment is configured to coat the coating liquid in a film shape on the upper surface of this base material 2 by discharging the coating liquid from the tip discharge hole of the nozzle portion 16 while conveying the film-shaped base material 2 facing this nozzle portion 16 with respect to this nozzle portion 16. appliedIt is provided on the downstream side of the conveying path of the coating device 1, and is configured to convey the film-shaped base material 2 whose upper surface has been coated by the coating device 1 and dry the coating film thereon.

[0032] Specifically, although not shown in the drawings, for example, it is composed of a drying chamber section 3 configured by arranging a plurality of main body sections (drying chamber forming sections 11) side by side on the left and right for conveying the film-shaped base material 2 through the left and right conveying inlets and outlets. (Although the drawing is simplified), a large number of supporting rollers 19 for supporting the base material 2 are provided at intervals in the drying chamber section 3, and hot air blowing sections 4 are provided above and below the base material 2 supported and conveyed by the supporting rollers 19 for hot air drying.

[0033] Specifically, a large number of the supporting rollers 19 are horizontally arranged in parallel in the drying chamber section 3, the film-shaped base material 2 is passed through the supporting rollers 19, and while the film-shaped base material 2 is pulled and horizontally conveyed, the coating surface (coating film) on the upper surface of the base material 2 is dried by the heat of the hot air from the hot air blowing section 4. Note that it may be configured to dry the coating surface (coating film) by a floating drying method while providing hot air blowing sections above and below and conveying it in a non-contact manner.

[0034] In this embodiment, hot air blowing sections 4 are provided below and above each of the supporting rollers 19 in the drying chamber section 3. Similar to the drying device having the configuration shown in the above-mentioned prior patent document developed by the applicant, a Coandă nozzle section 20 that generates a Coandă effect, that is, blows hot air in a predetermined direction to generate a force for pulling the base material 2 downward and causes an action of pressing and contacting the base material 2 against the supporting roller 19, is provided in the hot air blowing section 4 disposed below the supporting roller 19.

[0035] In this embodiment, it is configured to include a hot air generating section 5 that generates hot air to be sent to each of the hot air blowing sections 4 of each drying chamber forming section 11 of the drying chamber section 3 and sends the hot air to the hot air blowing sections 4.

[0036] Specifically, the hot air generation unit 5 that sends hot air into the hot air delivery unit 4 in the upstream side of the conveyance of the base material 2 in each drying chamber forming unit 11 of the drying chamber unit 3, that is, in the drying chamber forming unit 11 on the upstream side of conveyance where combustible gas may be generated until the coating film is dried to a certain extent, is configured as a path including a heater heating and generating unit 7 that heats the drawn-in air (outside air) with an electric heater unit 6 to generate hot air, a mixing unit 8 (in this embodiment, simply a pipeline junction) that draws in and mixes the heater-heated hot air generated by this heater heating and generating unit 7 and the exhaust hot air exhausted from the drying chamber unit 3 and blows out this mixed hot air, a blowing unit 9 for drawing in and blowing out due to this blowing negative pressure, and a filter 22. The mixed hot air at a desired temperature drawn in and mixed by this blowing unit 9 is blown out to each hot air delivery unit 4 of the drying chamber unit 3 in this manner through the filter 22.

[0037] More specifically, this hot air generation unit 5 of this embodiment draws in and mixes, due to the blowing negative pressure, the heater-heated hot air generated by the heater heating and generating unit 7 and the exhaust hot air that branches off a part of the exhaust hot air exhausted from the drying chamber unit 3 and draws in a predetermined amount through the valve 21, and provides the blowing unit 9 at the pipeline position where this drawn-in and mixed hot air is blown out to the hot air delivery unit 4 of the drying chamber unit 3. The exhaust hot air that may contain combustible gas or the like is configured such that it cannot be heated by the heater unit 6 of the heater heating and generating unit 7.

[0038] Also, in this embodiment, a hot air temperature control unit C is provided to control the mixing ratio of the heater-heated hot air and the exhaust hot air, the heating degree (heater heating power amount) of the heater unit 6, or the blowing degree (fan rotation speed) of the blowing unit 9 so that the temperature of the mixed hot air sent into each hot air delivery unit 4 becomes a desired temperature, for example, 120°C, and a predetermined flow rate.

[0039] Specifically, it may be configured to include a control unit that controls all of these. However, in this embodiment, for example, the adjustment setting of the valve 21 that circulates the exhaust hot air and the adjustment setting of the rotation speed of the blower unit 9 are set manually, and the heating intensity of the heater unit 6 is controlled according to the mixing ratio based on the temperature of the temperature sensor 10 that detects the temperature of the mixed hot air sent into the hot air delivery unit 4 for feedback control to reach the desired temperature.

[0040] For example, in order to improve energy efficiency, by setting the mixing ratio of the exhaust hot air to be circulated to 90% or 80%, the amount of outside air to be heated by the heater can be reduced to 10% or 20%. Also, since this exhaust hot air is at 90°C to 80°C and can be circulated and mixed in a predetermined amount, the degree of heating of the outside air drawn in by the heater unit 6 can be reduced. However, the less the amount of the outside air drawn in, the higher the temperature of the mixed hot air has to be raised to 120°C. Therefore, the output of the heater unit 6 has to be increased so that the temperature of the heated hot air by the heater becomes quite high, and it is difficult to increase the mixing ratio of the exhaust hot air too much. These are studied and adjusted to configure the above-mentioned respective parts for setting or control.

[0041] In this embodiment, taking such things into consideration, it is set and controlled according to the desired temperature, flow rate, and mixing ratio of the hot air. However, in this embodiment, the hot air temperature control unit C is configured to control the heating intensity of the heater unit 6 based on the temperature sensor 10.

[0042] Therefore, by only controlling the heating intensity (heater heating power) of the heater unit 6 hot air with the desired temperature and flow rate can be efficiently and simply supplied, and as described above, a hot air generation unit 5 with excellent energy efficiency in terms of environmental performance and safety can be realized.

[0043] Also, in this embodiment, as described above, a temperature sensor 10 for detecting the temperature of the mixed hot air to be sent to the hot air delivery section 4 of the drying chamber section 3 is provided, and the hot air temperature control section C is configured to control the heating intensity (heater heating power) of the heater section 6 based on the temperature detected by this temperature sensor 10, so that stable temperature control (temperature management) can be achieved and the drying performance of the hot air drying device can be maintained.

[0044] Also, in this embodiment, the drying chamber section 3 is configured such that a plurality of drying chamber forming sections 11 are arranged side by side in the conveyance direction of the base material 2, and the drying chamber forming section on the conveyance downstream side 11 The downstream hot air generation section 12 that generates hot air and sends it into the hot air delivery section 4 provided in the downstream hot air generation section 12 is not the hot air generation section 5 because sufficient drying has progressed and there is no risk of containing combustible gas at a dangerous concentration or higher. Instead, the downstream hot air generation section 12 that generates hot air to be sent into the drying chamber forming section 11 on the conveyance downstream side, that is, the drying end side, is a circulation mixing heater heating generation section 13 that heats the mixed hot air obtained by mixing the drawn-in air and the exhaust hot air exhausted from the drying chamber section 3 with a heater section 6 (the same heater section 6 as the hot air generation section 5) to generate a heater-heated mixed hot air, and the blower section 9. Also, in the same manner as the hot air generation section 5, a hot air temperature control section C is provided to control the mixing ratio of the outside air and the exhaust hot air, the heating degree (heater heating power amount) of the heater section 6, or the blowing degree (fan rotation speed) of the blower section 9. The heater-heated mixed hot air at a desired temperature generated by this circulation mixing heater heating generation section 13 is sent into the hot air delivery section 11 provided in the drying chamber forming section on the conveyance downstream side.

[0045] That is, the downstream hot air generation section 12 that generates hot air to be sent into the drying chamber forming section 11 on the drying end side is configured to heat the mixed hot air obtained by mixing the exhaust hot air and the outside air with a heater to send hot air at a desired temperature into the hot air delivery section 4 in order to further improve energy efficiency. As a result, a hot air drying device with even better energy efficiency can be realized.

[0046] In this embodiment, both the hot air generation unit 5 that sends hot air into the hot air delivery unit 4 on the upstream side of the conveyance and the downstream hot air generation unit 12 that sends hot air into the hot air delivery unit 4 on the downstream side of the conveyance are configured to include a gas sensor 14 for detecting the degree to which the exhaust hot air contains combustible gas, thereby monitoring the content of combustible gas and ensuring safety.

[0047] Note that the present invention is not limited to this embodiment, and the specific configurations of the respective constituent elements can be designed as appropriate.

Explanation of Reference Numerals

[0048] 1 Coating device 2 Base material 3 Drying chamber section 4 Hot air delivery unit 5 Hot air generation unit 6 Heater section 7 Heater heating generation unit 8 Mixing section 9 Blower section 10 Temperature sensor 11 Drying chamber forming section 12 Downstream hot air generation unit 13 Circulation mixing heater Heating generation unit 14 Gas sensor 15 Take-up roll 16 Nozzle section 17 opposite Support roller 18 Recovery roll 19 Support roller 20 Coandă nozzle section 21 Valve 22 Filter

Claims

1. In a hot air drying device provided with a hot air delivery section for delivering hot air for drying the coating liquid applied to a film-shaped base material that is coated with the coating liquid by a coating device and conveyed through the device, a hot air generation section for generating hot air to be fed into the hot air delivery section in the hot air drying section is provided, the hot air generation section for feeding hot air into the hot air delivery section at least on the upstream side of the conveyance of the base material in the hot air drying section includes a heater heating and generating section that heats the drawn-in air with an electric heater section to generate hot air, a mixing section that mixes the heater heating hot air generated by this heater heating and generating section and the exhaust hot air exhausted from the hot air drying section to send out mixed hot air, and a blower section, and is configured not to heat the exhaust hot air, and the mixed hot air drawn in and mixed by this blower section is configured to be sent out to the hot air delivery section in the hot air drying section, a hot air temperature control section is provided to control the heating degree of the heater section according to the mixing ratio of the heater heating hot air and the exhaust hot air so that the temperature of the hot air sent out to the hot air delivery section becomes a desired temperature, the hot air drying section is configured such that a plurality of hot air drying forming sections are arranged and connected in parallel in the conveyance direction of the base material, a downstream hot air generation section that generates hot air to be fed into the hot air delivery section provided in the hot air drying forming section on the downstream side of the conveyance of the base material, which is different from the hot air generation section on the upstream side of the conveyance, heats the mixed hot air in which the drawn-in air and the exhaust hot air exhausted from the hot air drying section are mixed with the electric heater section to generate heater heating mixed hot air, and consists of the blower section, and the heater heating mixed hot air generated by this circulation mixing heater heating and generating section is configured to be fed into the hot air delivery section provided in the hot air drying forming section on the downstream side of the conveyance. A hot air drying device characterized by the above. Claim 2: The hot air generation unit on the upstream side of the conveyance of the base material draws in and mixes the heater-heated hot air generated by the heater heating generation unit and the exhaust hot air exhausted from the drying chamber unit by means of a blowing negative pressure, and is provided with the blowing unit at a position where the mixed hot air obtained by this drawing-in and mixing is blown and sent out to the hot air sending-out unit of the drying chamber unit, and the exhaust hot air is configured not to be heated by the heater unit of the heater heating generation unit. The hot air drying device according to claim 1, characterized in that.

3. The drying device according to claim 1, characterized in that a temperature sensor for detecting the temperature of the mixed hot air sent out to the hot air sending-out unit of the drying chamber unit is provided, and the hot air temperature control unit is configured to control the heating intensity of the heater unit based on the temperature detected by this temperature sensor.

4. The hot air drying device according to claim 1, characterized in that it is configured to be provided with a gas sensor for detecting the degree to which the exhaust hot air contains combustible gas.

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