JP2012045480A - Gas replacement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas replacement device which blows a replacement gas to an object to replace therewith a space in the vicinity of the surface of the object and improves replacement efficiency.SOLUTION: In the gas replacement device which blows out the replacement gas 16 from a blowing-out port 23 to the surface of a carrying sheet-like web 11 to replace the atmosphere on the surface of the web 11 with the replacement gas 16, the blowing-out port 23 is formed in an opposite face 21 arranged so as to be parallel to the surface of the web 11, blows out the replacement gas 16 along the direction orthogonal to the surface of the web 11, and divides the opposite face 21 into an upstream side opposite face 24 on the upstream side of the blowing-out port 23 and an downstream side opposite face 25 on the downstream side thereof. A space between the upstream side opposite face 24 and the surface of the web 11 is set to be 0.5-3.5 mm.

Description

  The present invention relates to a gas replacement device that blows a replacement gas toward the surface of a sheet-like object and replaces the vicinity of the surface of the object with a replacement gas.

  2. Description of the Related Art Conventionally, as described in Patent Document 1, for example, a gas replacement device provided in a device that irradiates a coating agent with ultraviolet rays or an electron beam is known. The gas displacement device blows an inert gas such as nitrogen gas toward the coating agent when the coating agent applied to a sheet-like object such as paper or film is cured. As a result, oxygen present around the coating agent is replaced with an inert gas, thereby preventing the curing reaction of the coating agent, which is a radical polymerization reaction, from being inhibited by oxygen.

JP-T-2002-524239

  By the way, in the gas replacement apparatus described above, the inert gas may be expensive, and the oxygen around the coating agent is replaced with the inert gas with a smaller amount of the inert gas, that is, the replacement efficiency is strongly improved. It has been demanded. In the gas replacement device of Patent Document 1, although the shape of the blowout port for blowing out the inert gas and the distance between the blowout port and the surface of the object can be changed, the replacement efficiency in the vicinity of the surface of the object is improved. There was room for further improvement regarding the shape in the vicinity of the outlet.

  The present invention has been made in view of the above circumstances, and the object thereof is to improve the replacement efficiency in a gas replacement apparatus that blows a replacement gas onto an object and replaces the vicinity of the surface of the object with a replacement gas. The object is to provide a gas displacement device.

  In order to solve the above-described problems, the present invention includes a transport unit that transports a sheet-like object, and a blow-out unit that blows a replacement gas from a blow-out port toward the surface of the target object. In the gas replacement apparatus that replaces the atmosphere on the surface with the replacement gas, the blowing portion has a facing surface parallel to the surface of the object, and the blowing port is formed on the object from directly above the object. The replacement gas is blown to the surface, and the facing surface is partitioned by the blowing port into an upstream facing surface on the upstream side and a downstream facing surface on the downstream side in the conveying direction of the object, and the upstream facing surface The distance from the surface of the object is set to 0.5 mm or more and 3.5 mm or less.

  As a result of performing various simulations related to the shape near the outlet in order to improve the replacement efficiency in the vicinity of the surface of the object, the present inventor has found that the surface of the object that has passed through the gas replacement device has the above-described configuration. It has been found that the substitution efficiency is improved in the vicinity.

In the gas replacement device of the present invention, an upstream flow path is formed by the upstream facing surface and the surface of the object, and a downstream flow path is formed by the downstream facing surface and the surface of the object. Then, the replacement gas blown out from the blowout port is blown out onto the surface of the object, thereby functioning as a gas curtain, and is pulled by the object to be transported and enters the upstream flow path. The gas is prevented from flowing into the downstream channel. Further, part of the blown-out replacement gas flows into the upstream flow path, and the rest flows into the downstream flow path. At this time, the replacement gas flows into each flow channel in such a manner that it is bounced back to the surface of the object. Therefore, in the upstream flow channel, the replacement gas is pulled in the conveyance direction by the external gas so as to be pulled by the object to be conveyed. A flow is formed on the object side, and a flow in the direction opposite to the conveying direction by the flowing replacement gas is formed on the facing surface side. The external gas is peeled off from the object by the replacement gas flowing into the upstream channel after being blown onto the surface of the object, and is discharged from the upstream channel together with the replacement gas. Thereby, the external gas that has entered the upstream flow path is replaced with a replacement gas that flows into the downstream flow path. Then, by setting the distance between the upstream facing surface and the object to be 0.5 mm or more and 3.5 mm or less, the diffusion of the replacement gas blown from the blowout port or the decrease in the flow velocity of the replacement gas blown to the object is suppressed. Therefore, it is considered that the replacement efficiency is improved because the external gas is easily separated from the object.

Moreover, in the gas replacement apparatus of this invention, the length of the said conveyance direction in the said downstream opposing surface is set to 20 mm or more and 250 mm or less.
As in this gas replacement device, the replacement efficiency of the gas replacement device is further improved by setting the length in the transport direction on the downstream facing surface to 20 mm or more and 250 mm or less.

Moreover, in the gas replacement apparatus of this invention, the length of the said conveyance direction in the said upstream opposing surface is set to 5 mm or more and 150 mm or less.
Like this gas replacement apparatus, the replacement efficiency of the gas replacement apparatus is further improved by setting the length of the upstream facing surface in the transport direction to 5 mm or more and 150 mm or less.

In the gas replacement device of the present invention, the downstream facing surface is provided with a recess, and a swirling flow is formed in the recess.
The present inventor performs a simulation on the replacement efficiency of the gas replacement device, and further improves the replacement efficiency of the gas replacement device by providing a recess on the downstream facing surface and forming a swirl flow in the recess. I found.

  According to the gas displacement device having the above-described configuration, the downstream facing surface is provided with the recess, and a swirling flow corresponding to the flow in the downstream channel is formed in the recess. Here, in the downstream flow path, the concentration of the external gas increases as it approaches the object due to the external gas that has not been separated from the surface of the object, and the concentration of the replacement gas increases as it approaches the opposite surface. . A part of the gas flowing on the opposite surface side flows into the concave portion, so that a swirl flow is formed in the concave portion. For this reason, in the recess, the state in which the concentration of the replacement gas is high is maintained, and the inflow from the downstream channel and the outflow to the downstream channel are repeated. In the downstream flow path, the flow of gas away from the surface of the object is induced in the downstream flow path by the inflow into the recess, so that the external gas is in the vicinity of the surface of the object. The portion having a high concentration is easily diffused. Therefore, it is considered that the replacement efficiency near the surface of the object is further improved.

  According to the gas replacement device of the present invention, the replacement efficiency in the vicinity of the surface of the object can be improved.

The figure which shows typically schematic structure of the coating agent hardening system using the gas displacement apparatus which concerns on this invention. The figure which shows the structure of a gas displacement apparatus typically. The graph which shows an example of the relationship between the length of a downstream facing surface, and oxygen concentration. The graph which shows an example of the relationship between the length of an upstream opposing surface, and oxygen concentration. The graph which shows an example of the relationship between a gap and oxygen concentration. The figure which shows typically the structure of the gas displacement apparatus provided with the recessed part. The graph which shows an example of the relationship between the length of a downstream facing surface, and oxygen concentration. In the modification, the graph which shows an example of the relationship between the flow volume of substitution gas and oxygen concentration in the gas substitution apparatus provided with the recessed part.

  Hereinafter, an embodiment of a gas replacement device of the present invention will be described with reference to FIGS. First, a coating agent curing system using a gas displacement device will be described. FIG. 1 is a diagram schematically showing a schematic configuration of a coating agent curing system using a gas displacement device.

  As shown in FIG. 1, the coating agent curing system 10 includes a transport unit 12 that transports a sheet-like web 11 as an object and constitutes a gas displacement device. The transport unit 12 transports the web 11 in the transport direction in the chamber 13 from the transport inlet 13a toward the transport outlet 13b.

  In the chamber 13, a blowing unit 14 and an irradiating unit 15 constituting a gas replacement device are arranged in parallel in the transport direction. The blowing unit 14 blows a replacement gas (inert gas) 16 from the blowing port along the direction perpendicular to the surface of the web 11 to the web 11 conveyed by the conveying unit 12, and the surface of the web 11. The vicinity is replaced with the replacement gas 16. In addition, the blowing unit 14 also serves to fill the chamber 13 with the replacement gas 16. The irradiation unit 15 cures the coating agent applied to the surface of the web 11 by irradiating an energy beam 18 such as an electron beam or ultraviolet light to the web 11 whose surface is replaced with the replacement gas 16. Let

  The present inventor performed various simulations related to the shape near the outlet in order to improve the replacement efficiency of the gas replacement device used in the coating agent curing system 10 described above. Hereinafter, although the simulation by this inventor is demonstrated, first, the gas replacement apparatus used for simulation is demonstrated using FIG. FIG. 2 is a diagram schematically showing the structure of the gas replacement device, showing the outer shape of the blowing section 14, and arrows in the upstream channel 26 and the downstream channel 27 indicate the gas flow in each channel. Is schematically shown. In FIG. 2, the conveyance unit 12 is omitted.

  As shown in FIG. 2, the blowing section 14 is disposed so as to be parallel to the surface of the web 11, and is opposed to extend in the width direction of the web 11 (direction from the front side to the back side) perpendicular to the transport direction. It has a surface 21. Further, the blowing portion 14 has an end surface 22 that is perpendicular to the facing surface 21 at the end of the facing surface 21. A blowing port 23 for blowing the replacement gas 16 is formed on the facing surface 21 so as to extend along the normal direction of the surface of the web 11 with respect to the web 11. Therefore, the facing surface 21 is partitioned by the blowing port 23 into an upstream facing surface 24 that is upstream in the transport direction from the blowing port 23 and a downstream facing surface 25 that is downstream. An upstream flow path 26 is formed by the upstream facing surface 24 and the surface of the web 11, and a downstream flow path 27 is formed by the downstream facing surface 25 and the surface of the web 11.

In the gas replacement device having such a configuration, the external gas 28 in the external space 31 enters the upstream flow path 26 by being pulled by the transported web 11, but the replacement gas 16 blown out from the outlet 23 functions as a gas curtain. Therefore, it is possible to prevent the external gas 28 from entering the downstream channel 27 from the upstream channel 26. Further, the replacement gas 16 is supplied from the web 11.
After being sprayed on the surface, a part flows out to the external space 31 through the upstream channel 26 and the rest flows out to the external space 32 through the downstream channel 27. At this time, the replacement gas 16 flows into the flow paths 26 and 27 in such a manner that it is bounced back to the surface of the web 11. Therefore, in the upstream flow path 26, the flow in the transport direction by the external gas 28 in the external space 31 that has entered is formed on the web 11 side, and the flow in the direction opposite to the transport direction by the outflowing replacement gas 16 is upstream. It is formed on the facing surface 24 side. The external gas 28 is peeled off from the web 11 by the replacement gas 16 blown to the surface of the web 11, and is discharged from the upstream flow path 26 together with the replacement gas 16. As a result, the external gas 28 in the vicinity of the surface of the web 11 is replaced with the replacement gas 16 that flows into the downstream flow path 27.

Next, various conditions of the simulation performed for the gas replacement device described above will be described. In this simulation, “FLUENT ver12.0” (registered trademark, manufactured by ANSYS), which is thermal fluid analysis software, was used as analysis software, and various conditions were set as follows.
<Conditions for analysis>
・ 2D steady analysis ・ Mesh shape: Triangular and square hybrid mesh ・ Number of meshes: 36302
・ Turbulent model: Standard kε + extended wall function ・ Consideration of gravity ・ Relative velocity of fluid on the wall is “zero”
・ Diffusion coefficient: 2.14 × 10 ⁻⁵ m ² / s
<Web conditions>
・ Conveying speed: 200m / min
<Conditions related to external space>
・ External space 31, 32: Atmosphere (oxygen concentration 21%, nitrogen concentration 79%)
・ Viscosity: 1.79 × 10 ⁻⁵ Pa · s
Density: 1.225 kg / m ³
-Pressure in the external space: Atmospheric pressure-The external spaces 31, 32 are independent from each other and communicate with each other through the upstream flow path 26 and the downstream flow path 27.-Turbulent flow conditions when entering external gas: Turbulence intensity 10%, hydraulic diameter 1mm
<Conditions for replacement gas>
・ Replacement gas: inert gas (nitrogen 100%)
・ Viscosity: 1.79 × 10 ⁻⁵ Pa · s
Density: 1.225 kg / m ³
-Outlet: slit width Sw = 2 mm, width 500 mm in the width direction of the web 11
・ Flow rate: 320 L / min (equivalent to a flow rate of 5.33 m / s)
-Turbulent flow conditions when blowing: Turbulent strength 10% Hydraulic diameter 1 mm
<Conditions for evaluation>
Calculation of oxygen concentration at the measurement point MP of 70 μm from the surface of the web 11 at the outlet of the downstream flow path 27. Suitable range: 5 ppm or less. More preferred range: 1 ppm or less. The range in which the oxygen concentration at the measurement point MP at the exit of the pipe is 5 ppm or less is a suitable range, and the range of 1 ppm or less is a more preferred range. These criteria are derived from the fact that the cured state of the coating agent was good when the inventor produced a prototype of the coating agent curing system 10 based on the simulation results.
<Test Example 1>
First, conditions and results of Test Example 1, which is a simulation related to the length L2 of the downstream facing surface 25, will be described. In Test Example 1, the conditions were set as follows. There are no changes in the above-described analysis conditions, web conditions, external space conditions, replacement gas conditions, and evaluation conditions.
<Conditions of Test Example 1>
A gap G1 = 2.5 mm, which is the distance between the upstream facing surface 24 and the surface of the web 11
・ Length L1 of the upstream facing surface 24 = 18 mm
-Length L2 of downstream facing surface 25 = 2, 5, 10, 20, 30, 40, 47.75, 60, 75, 100, 150, 250 mm in total 12 types under the conditions of Test Example 1 in FIG. The result of simulation is shown. FIG. 3 is a graph showing the relationship between the length of the downstream facing surface and the oxygen concentration.

As shown in FIG. 3, it was recognized that the length L2 of the downstream facing surface 25 where the oxygen concentration at the measurement point MP is 5 ppm or less is 20 mm or more and 250 mm or less. Moreover, it was recognized that the length L2 of the downstream facing surface 25 where the oxygen concentration is 1 ppm or less is 30 mm or more and 250 mm or less. That is, the length of the downstream facing surface 25 was found to be 20 mm or more and 250 mm or less, more preferably 30 mm or more and 250 mm or less.
<Test Example 2>
Next, conditions and results of Test Example 2, which is a simulation related to the length L1 of the upstream facing surface 24, will be described. In Test Example 2, the conditions were set as follows. There are no changes in the above-described analysis conditions, web conditions, external space conditions, replacement gas conditions, and evaluation conditions.
<Conditions of Test Example 2>
・ Gap G1 = 2.5mm
-Length L2 of upstream facing surface 24 = 1, 2, 5, 10, 18, 30, 50, 75, 100, 150mm-Length L2 of downstream facing surface 25 = 47.75mm
FIG. 4 shows the results of simulation under the conditions of Test Example 2. FIG. 4 is a graph showing the relationship between the length of the upstream facing surface and the oxygen concentration.

As shown in FIG. 4, it was recognized that the length L1 of the upstream facing surface 24 where the oxygen concentration at the measurement point MP is 5 ppm or less is 5 mm or more and 150 mm or less. Moreover, it was recognized that the length L1 of the upstream facing surface 24 where the oxygen concentration is 1 ppm or less is 5 mm or more and 100 mm or less. That is, it was recognized that the length L1 of the upstream facing surface 24 was 5 mm or more and 150 mm or less, more preferably 5 mm or more and 100 mm or less.
<Test Example 3>
Next, the conditions and results of Test Example 3, which is a simulation related to the gap G1, which is the distance between the web 11 and the upstream facing surface 24, will be described. In Test Example 3, the conditions were set as follows. There are no changes in the above-described analysis conditions, web conditions, external space conditions, replacement gas conditions, and evaluation conditions.
<Conditions of Test Example 3>
・ Gap G1 between the upstream facing surface 24 and the surface of the web 11 = total of six types of 0.5, 1.5, 2.5, 3.5, 5, and 7 mm ・ Length L1 of the upstream facing surface 24 = 18mm
・ Length L2 of the downstream facing surface 25 = 47.75 mm
FIG. 5 shows the result of the shredding obtained in Test Example 3. FIG. 5 is a graph showing the relationship between the oxygen concentration and the gap G1, which is the distance between the upstream facing surface and the surface of the web.

As shown in FIG. 5, it was recognized that the gap G1 at which the oxygen concentration at the measurement point MP is 5 ppm or less is 0.5 mm or more and 3.5 mm or less. The oxygen concentration is 1p
It was recognized that the gap G1 which is pm or less is 0.5 mm or more and 2.5 mm or less. That is, the gap G1 was found to be 0.5 mm or more and 3.5 mm or less, more preferably 0.5 mm or more and 2.5 mm or less. The lower limit of 0.5 mm of the gap G1 is an interval necessary for preventing the web 11 being conveyed from coming into contact with the facing surface 21 due to vibrations accompanying the conveyance.
<Test Example 4>
Further, the present inventor conducted various simulations on the shape near the outlet, and provided a recess in the downstream facing surface 25 to form a swirl flow in the recess, thereby improving the replacement efficiency of the gas replacement device. It has been found that further improvement. A gas displacement device provided with the recess will be described with reference to FIG. FIG. 6 is a diagram schematically showing the structure of a gas displacement device provided with a recess, showing the outer shape of the blowing section 14, and arrows in the upstream flow path 26 and the downstream flow path 27 indicate the respective flow. The flow of the gas in a path is shown typically. In FIG. 6, the conveying unit 12 is omitted.

  As shown in FIG. 6, the blowout portion 14 is provided with one recess 35 on the downstream facing surface 25. The recess 35 has an inner peripheral surface constituted by a bottom surface 35a and an end surface 35b, and is formed to extend in the width direction. A projection 36 is formed in the vicinity of the outlet of the downstream channel 27 by the recess 35. Of the gas flowing through the downstream flow path 27, a part of the gas flowing away from the surface of the web 11 flows into the recess 35, so that the recess 35 has an inner peripheral surface as shown in FIG. 6. A swirling flow is formed. Here, in the downstream flow path 27, the concentration of the external gas 28 increases as it approaches the web 11 due to the external gas 28 that has not been separated from the surface of the web 11, and conversely, the concentration of the replacement gas 16 increases as the distance from the web 11 increases. Tend to be higher. Therefore, the high concentration of the replacement gas 16 is maintained in the recess 35 into which the gas flowing away from the web 11 flows. Further, the swirl flow is formed in the recess 35, whereby the inflow from the downstream channel 27 and the outflow to the downstream channel 27 are repeated in the recess 35. Since the flow into the recess 35 induces a flow away from the surface of the web 11, the vicinity of the surface of the web 11, that is, the portion where the concentration of the external gas 28 is high is easily diffused. Therefore, it is considered that the replacement efficiency near the surface of the web 11 is further improved.

Next, conditions and results of Test Example 4 in which a simulation is performed on the gas replacement device provided with the above-described recess 35 will be described. In Test Example 4, the conditions were set as follows. There are no changes in the above-described analysis conditions, web conditions, external space conditions, replacement gas conditions, and evaluation conditions.
<Conditions of Test Example 4>
・ Gap G1 between the upstream facing surface 24 and the surface of the web 11 = 2.5 mm
・ Gap G2 between the downstream facing surface 25 and the surface of the web 11 = 5 mm
・ Length L1 of the upstream facing surface 24 = 18 mm
-Length L2 of the downstream facing surface 25 = 30, 40, 47.75, 60, 75, 100, 150, 250 mm in total- Length L3 of the protrusion 36 = 10 mm
-Height H of the protrusion 36 is less than 10 mm (length L2 is 30 to 40 mm), 10 mm (length L2 is 47.75 mm or more)
The recess 35 is formed on the basis of the length L2 of the downstream facing surface 25 being 47.75 mm, and the inclination of the bottom surface 35a of the recess 35 with respect to the surface of the web 11 is the length of the downstream facing surface 25. Constant regardless of L2. That is, when the length L2 of the downstream facing surface 25 is smaller than 47.75 mm, the concave portion 35 maintains the length L3 of the protruding portion 36 and the end surface 35b of the concave portion 35 according to the difference of the length L2. It is translated in the direction opposite to the transport direction. Therefore, in the range where the length of the downstream facing surface 25 is 30 to 40 mm, the height H of the protruding portion 36 is less than 10 mm. On the contrary, when the length L2 of the downstream facing surface 25 is larger than 47.75 mm, the recess 35 is recessed according to the difference of the length L2 while maintaining the length L3 and the height H of the protrusion 36. The end surface 35b of 35 is translated in the transport direction. That is, the concave portion 35 at this time is constituted by a surface whose bottom surface 35 a is inclined with respect to the surface of the web 11 and a surface parallel to the surface of the web 11.

  FIG. 7 shows the result of the simulation obtained in Test Example 4. FIG. 7 is a graph showing the relationship between the length of the downstream facing surface and the oxygen concentration. In addition, in FIG. 7, the result of the said test example 1 was also shown as a comparison object.

  As shown in FIG. 7, in Test Example 4, it is recognized that the oxygen concentration is lower than Test Example 1 in which the recess 35 is not provided, and that the oxygen concentration is 1 ppm or less under all conditions. It was. That is, it was recognized that the gas replacement device in which the concave portion 35 is provided on the downstream facing surface 25 has improved replacement efficiency compared to the gas replacement device in which the concave portion 35 is not provided.

  Even when the concave portion 35 was provided in the condition of Test Example 3, a better result was obtained than the simulation result of Test Example 3 shown in FIG. Therefore, even when the recess 35 is provided, the gap G1 which is the distance between the upstream facing surface 24 and the surface of the web 11 can be in the same range as the result obtained in Test Example 3. it can.

As described above, according to the present embodiment, the effects listed below can be obtained.
(1) In the gas displacement device of the above embodiment, the air outlet 23 is formed on the facing surface 21 arranged so as to be parallel to the surface of the web 11, and is orthogonal to the surface of the web 11 from the air outlet 23. The replacement gas 16 was blown out along the direction. Further, the facing surface 21 is configured by an upstream facing surface 24 and a downstream facing surface 25 in the conveyance direction of the web 11, and a distance between the upstream facing surface 24 and the surface of the web 11 is 0.5 mm or more and 3.5 mm. It was observed that the substitution efficiency was improved if:

  By adopting such a configuration, the diffusion of the replacement gas 16 blown out from the blow-out port 23 and the decrease in the flow velocity of the replacement gas 16 blown to the web 11 are suppressed, and the external gas 28 is easily separated from the web 11, thereby reducing the gas. It is considered that the replacement efficiency of the replacement device is improved.

  (2) From Test Example 1 above, it is recognized that the replacement efficiency of the gas replacement device is further improved by setting the length L2 of the downstream facing surface 25 to 20 mm to 250 mm, more preferably 30 mm to 250 mm. It was.

  (3) From Test Example 2 above, it is recognized that the replacement efficiency of the gas replacement device is further improved by setting the length L1 of the upstream facing surface 24 to 5 mm to 150 mm, more preferably 5 mm to 100 mm. It was.

  (4) From Test Example 4 described above, a recess 35 is provided in the downstream facing surface 25 and a swirling flow is formed in the recess 35, thereby inducing a flow away from the surface of the web 11 in the downstream flow path 27. Therefore, it was recognized that the replacement efficiency in the vicinity of the surface of the web 11 was further improved.

(5) In Test Example 4, the gap G2 that is the distance between the downstream facing surface 25 and the surface of the web 11 is made larger than the gap G1 that is the distance between the upstream facing surface 24 and the surface of the web 11. According to such a configuration, the flow passage cross-sectional area in the downstream flow passage 27 is larger at the outlet than at the inlet (immediately after the blow-out port 23), so that a flow away from the surface of the web 11 is easily induced. Thereby, the replacement efficiency in the vicinity of the surface of the web 11 can be further improved.

  (6) By applying the gas replacement device with improved replacement efficiency to the coating agent curing system 10 as in the above-described embodiment, the irradiation unit 15 disposed on the downstream side of the gas replacement device can efficiently perform the vicinity of the surface. The energy beam 18 is applied to the web 11 that is often replaced with the replacement gas 16. That is, it is possible to make the curing state of the coating agent by the coating agent curing system 10 better. The irradiation of the energy beam 18 by the irradiating unit 15 may be performed on the downstream side of the gas replacement device. However, in order to maintain the concentration of the replacement gas in the vicinity of the surface, it is preferable that the energy beam 18 is close to the gas replacement device.

In addition, the said embodiment can also be suitably changed and implemented as follows.
In the above embodiment, one recess 35 is provided on the downstream facing surface 25. By changing this, a plurality of recesses in which a swirl flow is formed may be formed along the conveyance direction, or a plurality of recesses may be formed along the width direction of the web 11. In addition, as long as a swirl flow is formed in the recess, the shape of the recess is not limited to the shape of the recess 35 described in the above embodiment.

  In Test Example 4 of the above embodiment, that is, in the case where the concave portion 35 is provided, the surface of the web 11 and the downstream facing surface 25 rather than the gap G1 that is the distance between the surface of the web 11 and the upstream facing surface 24 The gap G2 which is the interval of is increased. By changing this, the gap G1 and the gap G2 may be made equal, or the gap G2 may be smaller than the gap G1. Even if it is such a structure, the effect similar to the effect described in said (4) can be acquired.

  In the above embodiment, the length L1 of the upstream facing surface 24 is 5 mm or more and 150 mm or less, more preferably 5 mm or more and 100 mm or less. The length L1 of the upstream facing surface 24 is such that the distance between the upstream facing surface 24 and the surface of the web 11 is 0.5 mm or more and 3.5 mm or less, and the length of the downstream facing surface 25 is 20 mm or more and 250 mm. If it is the following, it is not restricted to the said range.

  In the above embodiment, the length L2 of the downstream facing surface 25 is 20 mm or more and 250 mm or less, more preferably 30 mm or more and 250 mm or less. The length L2 of the downstream facing surface 25 is such that the distance between the upstream facing surface 24 and the surface of the web 11 is not less than 0.5 mm and not more than 3.5 mm, and the upstream facing surface 24 is provided. It is not limited to the above range.

  In the above-described embodiment, the air outlet 23 is formed to extend over the entire area in the width direction of the web 11 on the facing surface 21. However, the blowout port is not limited to this, and the blowout port may be formed of a blowout group in which the webs 11 extending in the width direction of the web 11 are arranged in parallel in the width direction.

  -From the blow-out port 23 of the gas substitution apparatus of the said embodiment, it is possible to blow out substitution gas according to the use not only as inert gas, such as said nitrogen gas, as substitution gas. For example, in the case of drying an object with water droplets, dry air or heated air may be used as a replacement gas.

FIG. 8 shows a graph of the relationship between the flow rate of the replacement gas 16 and the oxygen concentration when the length L2 of the downstream facing surface 25 is 47.75 mm in Test Example 4 of the above embodiment. As shown in FIG. 8, the flow rate of the replacement gas 16 was set to 320 L / min (corresponding to a flow rate of 5.33 m / s) in Test Example 4, but the oxygen concentration near the surface of the web 11 according to the flow rate of the replacement gas 16. Therefore, it is preferable to change the flow rate of the replacement gas 16 according to the occasional request.

  The gas replacement apparatus according to the present invention can be applied to an apparatus that performs predetermined processing on an object after the vicinity of the surface of the object is replaced with a replacement gas.

  H: Height, G1, G2 ... Gap, L1, L2, L3 ... Length, MP ... Measurement point, 10 ... Coating agent curing system, 11 ... Web, 12 ... Conveying section, 13 ... Chamber, 13a ... Inlet, 13b ... Exit port, 14 ... Blowout part, 15 ... Irradiation part, 16 ... Substitution gas, 18 ... Energy beam, 21 ... Confronting surface, 22 ... End face, 23 ... Blowout port, 24 ... Upstream facing surface, 25 ... Downstream side Opposing surface, 26 ... upstream channel, 27 ... downstream channel, 28 ... external gas, 31,32 ... external space, 35 ... concave, 35a ... bottom surface, 35b ... end surface, 36 ... projection.

Claims (4)

A transport unit for transporting a sheet-like object;
A blowing part that blows out a replacement gas from the blowing port toward the surface of the object;
In the gas replacement apparatus for replacing the atmosphere on the surface of the object with the replacement gas,
The blowing portion has a facing surface parallel to the surface of the object,
The outlet blows the replacement gas from directly above the object onto the surface of the object,
The facing surface is partitioned by the blowout port into an upstream facing surface on the upstream side and a downstream facing surface on the downstream side in the conveyance direction of the object,
The gas replacement device, wherein a distance between the upstream facing surface and the surface of the object is set to 0.5 mm or more and 3.5 mm or less. The gas replacement device according to claim 1, wherein a length in the transport direction on the downstream facing surface is set to 20 mm or more and 250 mm or less. The gas replacement device according to claim 2, wherein a length in the transport direction on the upstream facing surface is set to 5 mm or more and 150 mm or less. The gas replacement device according to any one of claims 1 to 3, wherein a concave portion is provided on the downstream facing surface, and a swirling flow is formed in the concave portion.

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