KR101584710B1 - UV curing apparatus enforced nitrogen density - Google Patents

Abstract

The present invention relates to an ultraviolet (UV) hardening device which hardens a UV coating agent using UV light and, more specifically, to a UV hardening device with a reinforced nitrogen atmosphere and an increased hardening quality of a UV coating agent by reinforcing nitrogen atmosphere in a chamber irradiating UV light. The hardening device according to the present invention comprises: a drum where a film applied with the UV coating agent passes through; a semicylindrical chamber unit covering the drum so as to form the chamber; a UV lamp module irradiating UV light onto the chamber in the chamber unit; a nitrogen nozzle discharging nitrogen out to the chamber in the chamber unit; and a nitrogen knife member disposed on both sides of the chamber unit in a longitudinal direction and discharging nitrogen so as to prevent external air from being introduced into the chamber.

Description

A UV curing apparatus enforced nitrogen density enhanced nitrogen atmosphere,

The present invention relates to a UV curing apparatus for curing a UV coating using ultraviolet rays, and more particularly, to a UV curing apparatus for enhancing a curing quality of a UV coating by strengthening a nitrogen atmosphere in a chamber for irradiating UV (ultraviolet) .

The coating is to coat the surface of the object with a thin film such as resin to prevent damage (eg, scratch) on the surface of the object, to prevent foreign matter such as dust from adhering to the object surface, to adjust the reflectance of the object surface Coating is the reason.

Although there are many kinds of coating methods, UV curing coatings having advantages such as high curability, high hardness, and chemical resistance of coated coatings have been recently used in many cases, .

The UV curing coating is a coating method in which UV (ultraviolet) is irradiated to the surface of an object coated with a coating agent to cure the coating agent to form a coating.

UV cured coatings are very short, with a cure rate between seconds and tens of seconds, which is advantageous for continuous film coating. That is, a UV cured coating is suitable for coating such that the film coated with the coating agent is continuously passed through the irradiation chamber for irradiating UV.

However, UV is absorbed by oxygen in the air to generate ozone, and oxygen in the air inhibits the chemical reaction of the UV coating with the outward light (i.e., UV) to lower the curing density of the coating.

Therefore, in the above-mentioned Japanese Patent Application No. 10-1032398, "UV curing apparatus using nitrogen purge apparatus", and registered patent No. 10-1435288 "coating method of steel sheet using ultraviolet curing coating", inert gas Nitrogen) is injected to lower oxygen tension.

However, the conventional techniques such as the above-mentioned Japanese Patent No. 10-1032398 "UV curing apparatus using nitrogen purge apparatus" and the registered patent No. 10-1435288 "coating method of steel sheet using ultraviolet curing coating" In other words, it only provides a conceptual description that it is desirable to lower the oxygen concentration in the chamber), but does not provide a specific technique on how to lower the oxygen concentration.

For reference, the optical films used in the display fields such as LCD, OLEDI, and PDP, when cured in an oxygen atmosphere, oxidize the coating agent with oxygen in the atmosphere to weaken the optical function.

Thus, the UV coating of the optical film is generally coated and cured in a nitrogen atmosphere.

The present invention was conceived to overcome the limitations of the prior art, which suggests that it is desirable to lower the oxygen concentration in the chamber in the UV curing coating process,

(EN) A UV curing apparatus having a substantial structure capable of strengthening a nitrogen atmosphere inside a chamber (that is, minimizing oxygen concentration)

It is another object of the present invention to provide a UV curing apparatus which is simple in operation for strengthening a nitrogen atmosphere and is enhanced in nitrogen atmosphere to prevent safety accident caused by discharged nitrogen.

In order to achieve the above-mentioned object, a UV curing apparatus reinforced with nitrogen atmosphere according to the present invention comprises:
A drum through which the film coated with the UV coating passes;
A chamber unit having a semi-cylindrical structure for forming a chamber surrounding the drum;
A UV lamp module for irradiating the chamber of the chamber unit with UV light;
A nitrogen nozzle for discharging nitrogen into the chamber of the chamber unit;
A nitrogen knife member disposed in both longitudinal sides of the chamber unit for discharging nitrogen to block external air from entering the chamber;
An actual panel disposed at an edge of the chamber unit and arranged in both the longitudinal direction and the both-side arc direction of the drum;
And a gap adjusting member for adjusting the gap with respect to the drum by respectively moving the yarn panels arranged in both the longitudinal direction and the both-side arc direction of the drum,
Wherein the nitrogen knife member discharges nitrogen to a portion where the film is in close contact with the drum,
The sealing panel is made of Teflon resin,

Wherein the gap adjusting member comprises: a fixing block fixedly coupled to the mounting plate of the chamber unit; an adjusting bolt screwed to the fixing block to move up and down; And a bracket coupled to the door panel so as to idly rotate together with the adjusting bolt to adjust the position of the door panel.
And the chamber unit
An upper frame and a lower frame arranged at the upper and lower sides and arranged in the longitudinal direction on the upper and lower sides of the drum,
A arc frame connected to both ends of the upper frame and the lower frame and having an arcuate shape and arranged at the outer periphery of the drum,
A plurality of compartment frames for connecting the two call frames on both sides in the longitudinal direction to form an arrangement space in which the UV lamp modules are arranged,
A plurality of transparent plates that cover the arrangement space and allow the ultraviolet rays emitted from the UV lamp module to pass therethrough while blocking inflow of outside air;
And a mounting plate mounted on the adjacent two section frames and on which the transparent plate is mounted,
The transparent plates are seated so as to be continuous with the mounting grooves formed in the periphery of the front opening of the mounting plate, and a blocking plate is disposed at a portion where the transparent plate and the transparent plate meet to cover the clearances between the transparent plates, And the pressure plate is fixed to the mounting plate so as to press the blocking plates toward the mounting plate so that the blocking plate seals the gap between the two transparent plates by the pressure of the blocking plate, And the gap is tightly sealed with the mounting plate so as to block the inflow of the outside air.

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And an exhaust duct disposed in both longitudinal sides of the chamber unit for sucking and removing nitrogen flowing out of the chamber,

A housing in which the chamber unit is mounted;

Forward and backward means for causing the housing to advance and retract;

And a stopper that restricts a forward range of the housing by the forward / backward means.

The UV curing apparatus having the nitrogen atmosphere enhanced according to the present invention as described above is characterized in that in addition to discharging nitrogen into the inner chamber of the chamber unit forming the chamber to which UV is applied by wrapping the drum through which the film coated with the coating agent passes, Nitrogen is injected into the gap between the drum and the chamber unit to block external air from flowing into the chamber, thereby enhancing the nitrogen atmosphere of the chamber, thereby enabling high-quality coating and minimizing the clearance between the drum and the chamber unit A UV curing apparatus reinforced with a nitrogen atmosphere which can enhance the nitrogen atmosphere and can easily operate the gap regulating member and can prevent accident caused by nitrogen by sucking and discharging nitrogen leaked to the surroundings through the exhaust duct It is a very useful invention for industrial development.

1 is a side view showing a schematic structure of a UV curing apparatus reinforced with a nitrogen atmosphere according to the present invention.
2 is a perspective view of a UV curing device reinforced with a nitrogen atmosphere according to the present invention.
3 is a perspective view showing the chamber unit and its surrounding components;
FIG. 4 is an exploded perspective view of FIG. 3; FIG.
Fig. 5 is a partial cutaway perspective view of Fig. 3; Fig.

Hereinafter, a UV curing apparatus having a nitrogen atmosphere enhanced according to the present invention will be described in detail with reference to the drawings.

Before describing the present invention in more detail,

While the present invention has been described in connection with certain embodiments, it is obvious that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the drawings, the same reference numerals are used for the same reference numerals, and in particular, the numerals of the tens and the digits of the digits, the digits of the tens, the digits of the digits and the alphabets are the same, Members referred to by reference numerals can be identified as members corresponding to these standards.

In the drawings, the components are expressed by exaggeratingly larger (or thicker) or smaller (or thinner) in size or thickness in consideration of the convenience of understanding, etc. However, It should not be.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the term " comprising " or " consisting of ", or the like, refers to the presence of a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

As shown in the figure, the UV curing apparatus having enhanced nitrogen atmosphere according to the present invention includes a drum 10, a chamber unit 20, a UV lamp module 30, a nitrogen nozzle 40, a nitrogen knife member 50, A stopper member 60, a gap regulating member 70, an exhaust duct 80, a housing 90, forward and backward means 100, a stopper 110, a pedestal 120, and the like.

On the drum 10, a film 1 coated with a UV coating is adhered to the surface.

2, guide rollers 11 and 12 for guiding the film 1 to be drawn in and pulled out from the drum 10 are provided on the front (left) upper and lower sides of the drum 10, respectively, The film 1 coated with the supply reel around which the film 1 is wound and the UV curing device is supplied to the front of the guide rollers 11 and 12 so as to supply the film 1 to the UV curing device, Is provided with a take-up reel.

The two guide rollers 11 and 12 guide the movement of the film 1 pulled into and drawn out of the drum 10 and tension the film 1 so that the film 1 is stretched so that the film 1 is wound on the surface of the drum 10 Tightly. At this time, it is preferable that two guide rollers are disposed so that the film 1 is brought into close contact with the surface of the drum 10 in a circumferential direction by more than half.

For reference, the UV coating is applied to the surface of the film 1 between the supply reel and the guide rollers.

The chamber unit 20 covers the rear side (the right side in the figure) of the drum 10 and forms a chamber 21 with the drum 10.

The chamber unit (20)

An upper frame 22 and a lower frame 23 disposed on the upper and lower sides and arranged in the longitudinal direction on the upper side and the lower side of the drum 10,

A call frame 24 connected to both ends of the upper frame 22 and the lower frame 23 and having an arcuate configuration and disposed at the outer periphery of the edge of the drum 10,

A partition frame 25 connecting the two arc frames 24 on both sides in the longitudinal direction to form an arrangement space 251 in which the UV lamp module is disposed,

A transparent plate 26 covering the arrangement space 251 to block ultraviolet rays emitted from the UV lamp module 30 while blocking inflow of outside air,

And a mounting plate 27 mounted on the two partition frames 25 and on which the transparent plate 26 is mounted.

The transparent plate 26 is made of a transparent material such as glass or quartz excellent in transparency.

It is advantageous to use one of the transparent plates 26 having a size capable of covering the entire opening 271 of the mounting plate 27 connected to the arrangement space 251 to prevent penetration of the outside air, There is a large risk of damages such as breakage during handling, and it is not easy to attach the mounting plate 27 to the mounting plate 27. In the present invention, a plurality of small transparent plates 26 are successively used, and a transparent blocking plate 261 is disposed at a position where the transparent plate 26 meets the transparent plate 26, Closing the gap between the two.

The transparent plates 26 are seated so as to be continuous with the seating grooves 273 formed around the front opening 271 of the mounting plate 27. The transparent plate 26 is provided at a position where the transparent plate 26 meets the transparent plate 26 The blocking plate 261 is disposed to cover the clearance between the transparent plates 26. A pressing plate 263 is disposed on the upper and lower sides of the blocking plates 261. The pressing plate 263 is fixed to the mounting plate 27 And presses the blocking plates 261 toward the mounting plate 27 side. The blocking plate 261 closes the gap between the two transparent plates 26 and the transparent plate 26 is brought into close contact with the seating groove 273 of the mounting plate 27, (27) to block the inflow of outside air.

The UV lamp module 30 includes a lamp (not shown) for emitting ultraviolet rays and a case 31 containing a lamp.

The UV lamp module 30 may be mounted directly on the chamber unit 20 but requires relatively large maintenance such as replacement of the lamp and is not required to be mounted on the chamber unit 20 when mounted directly on the chamber unit 20. [ It is possible to cause a deformation of the chamber unit 20 by giving a load by a load to the chamber unit 20 so that the chamber unit 20 is coupled to the housing 90 on which the chamber unit 20 is mounted and is disposed in the arrangement space 251 of the chamber unit 20 desirable.

The nitrogen nozzle 40 discharges nitrogen into the chamber 21 of the chamber unit 20 to convert the chamber 21 into a nitrogen atmosphere. That is, the chamber 21 is filled with nitrogen to lower the oxygen concentration in the chamber 21.

The nitrogen nozzles 40 are arranged on both sides of the partition frame 25, that is, in front of the mounting plate 27 in the longitudinal direction so as not to interfere with the ultraviolet irradiation of the UV lamp module 30.

The nitrogen nozzle 40 is connected to the arc frame 24 of the chamber unit 20 and has a pipe structure in which discharge holes 41 are formed at regular intervals. So that the direction of the discharge hole can be adjusted so as not to adversely affect the curing of the coating of the coating layer.

The nitrogen knife member 50 is disposed on both sides in the longitudinal direction of the chamber unit 20, that is, in front of both the upper and lower sides of the chamber unit 20, and discharges nitrogen to the chamber unit 20 and the drum 10 To prevent the outside air from penetrating into the chamber 21. Of course, the nitrogen in the chamber 21 is also prevented from flowing out.

The nitrogen knife member 50 has a discharge port formed in its entire length in the longitudinal direction so as to discharge nitrogen in the form of a thin film and has a sharp tip.

Nitrogen discharged from the upper portion and the lower portion of the chamber unit 20 respectively hit the film 1 passing the drum 10 through the nitrogen knife member 50. If nitrogen, which is discharged from the nitrogen knife member 50, collides with the film 1 and causes deformation such as pressing of the film 1, the coating quality may be deteriorated. Therefore, it is preferable that the nitrogen knife member 50 does not cause deformation of the film 1 by discharging nitrogen to the portion where the film 1 is in close contact with the drum 10. [

The seal panel 60 is mounted on the upper and lower frames 22 and 23 of the chamber unit 20 in both longitudinal and lateral directions of the chamber unit 20, 24 of the chamber 21 and minimizes leakage of nitrogen in the chamber 21 to the outside by allowing the outside air to penetrate into the chamber 21 as close as possible to the drum 10 through the gap regulating member 70.

Since the seal panel 60 is as close to the drum 10 as possible and the film 1 passing through the drum 10 may sometimes come into contact with the drum 10, It is preferable to use a material. Teflon resin may be used as a material having a small coefficient of friction.

The clearance adjusting member 70 is positioned so that the position of the seal panel 60 is minimized so as to be as close as possible (e.g., 1 mm or less) to the drum 10 at a line where the operator does not touch the film 1 by hand Make fine adjustments.

The gap regulating member 70 includes a fixing block 71 fixed to the mounting plate 27 of the chamber unit 20, an adjusting bolt 73 coupled to the fixing block 71, And a bracket 75 for connecting the seal panel 73 and the seal panel 60 and moving the seal panel 60 according to the rotation of the adjustment bolt 73.

The adjusting bolt 73 is screwed to the fixing block 71 so that it can be raised and lowered by the fixing block 71. The bracket 75 is coupled to the adjusting bolt 73 idly So that the position of the seal panel 60 can be adjusted by moving up and down with the bolts 73. On the other hand, the adjustment bolt 73 is idly coupled to the fixed block 71. The bracket 75 is screwed to the adjustment bolt 73, It is possible to adjust the position of the seal panel 60 by moving up and down the control bolt 75 along the adjustment bolt 73.

The seal panel 60 is brought into tight contact with the upper and lower frames 22 and 23 or the arc frame 24 of the chamber unit 20 by adjusting the position of the seal panel 60, Even if the weir seal panel 60 moves, the close contact structure between them is maintained.

The exhaust duct 80 is disposed on both sides of the chamber unit 20 in the longitudinal direction, that is, on the upper and lower sides of the chamber unit 20 to suck and remove nitrogen flowing out of the chamber 21.

More specifically, when the nitrogen in the chamber 21 flows out to the outside, the surrounding oxygen concentration is lowered and the safety of the operator can be prevented. Therefore, when the oxygen concentration around the chamber 21 is lowered, When the concentration of oxygen reaches the level required for the safety of the operator, the exhaust duct 80 absorbs the air having a large amount of nitrogen around the exhaust duct 80 and discharges the air to the outside to secure the safety of the operator.

The exhaust duct 80 and the nitrogen knife member 50 are provided not only on the front side of the chamber unit 20 but also on the left and right sides of the chamber unit 20 so as to suck and remove nitrogen discharged in the arc direction to block the outside air to be infiltrated.

The chamber unit 20, the UV lamp module 30, the nitrogen knife member 50, the exhaust duct 80, and the like are mounted on the housing 90. The housing 90 covers the left and right sides of the chamber unit 20.

The housing 90 is mounted on the pedestal 120 and moves back and forth on the pedestal 120 through the forward and backward means 100.

The forward and backward means 100 includes a guide rail 101 formed on the pedestal 120 and guiding the forward and backward movement of the housing 90 and the housing 90 through a piston 103 And a cylinder 105 for pulling the cylinder 105 forward and backward.

The stopper 110 limits the advance range of the housing 90 moving forward and backward.

The stopper 110 is provided at a front end of the contact block 111 or the piston 103 and a contact block 111 provided at the pedestal 120 so as to be positioned in the maximum advance range of the piston 103 And a limit switch 113 for sensing when the front end of the advanced piston 103 contacts the contact block 111. [ The contact block 111 and the piston 103 are in contact with each other when the limit switch 113 provided on the contact block 111 contacts the front end of the piston 103 or when the front end of the piston 103 contacts Quot; is contacted with the limit switch 113 provided in the block 111. [

When the contact of the piston 103 with the contact block 111 is detected, the limit switch 113 transmits the contact to the controller, and the cylinder stops driving under the control of the controller, Allow forward movement to stop.

The stopper 110 configured as described above is also provided in the maximum reverse range of the piston 103 to limit the backward range of the housing 90.

The present invention aims at minimizing the gap between the drum (10) and the chamber unit (20) so that nitrogen in the chamber (21) flows out to the outside, and that external air penetrates the chamber (21) It is preferable to set the advance range of the housing 90 by the forward and backward means 100 and the stopper 110 as far as possible to the position where the gap between the drum 10 and the chamber unit 20 is minimized.

Therefore, the contact block 111 is provided with an adjusting pin 115 that can adjust the position of contact with the front end of the piston 103. The adjustment pin 115 is screwed to the contact block 111 and is movable forward and backward within a predetermined range so that the operator can arbitrarily adjust the contact position of the contact block 111 and the piston 103 within the range.

The procedure for setting the gap between the drum 10 and the chamber unit 20 through the forward / backward means 100, the stopper 110 and the gap regulating member 70 is as follows.

First, the housing 90 is retracted through the forward / backward means 100 to move the chamber unit 20 away from the drum 10.

Next, two or more dummy films are closely contacted to the drum 10 and wound. Here, winding of two or more rolls takes into account the coating material applied to the process film (1). At this time, the entire dummy film should not be more than 1 mm.

Next, the gap adjusting member 70 is loosened so that the seal panel 60 is advanced.

Next, the housing 90 is advanced through the forward / backward means 100, and when the seal panel 60 of the chamber unit 20 comes into contact with the dummy film of the drum 10, And the adjustment pin 115 is adjusted so that the limit switch 113 of the stopper 110 contacts the front end of the piston 103 (or the contact block 111).

Next, the housing 90 is retracted through the forward / backward means 100, and the gap regulating member 70 is tightened to fix the seal panel 60 at that position.

The dummy film is removed and the drum 10 and the chamber unit 20 are placed in the processing chamber 1 after the process film 1 is installed. More specifically the gap between the film 1 of the drum 10 and the seal panel 60 of the chamber unit 20 can be minimized to the level of 0.1 to 0.2 mm.

After setting the gap between the drum 10 and the chamber unit 20 and installing the film for processing 1, nitrogen is first supplied into the chamber 21 without transferring the film 1, So that the UV lamp module 30 emits ultraviolet rays. Thereafter, the process film 1 is transferred to perform the UV curing operation.

Although not shown in the drawings, the present invention is characterized in that it comprises a nitrogen supplier for supplying nitrogen to the nitrogen nozzle 40 and the nitrogen knife member 50, an internal sensor for measuring the nitrogen concentration (or oxygen concentration) in the chamber 21 And a control unit for controlling the driving of the nitrogen supply unit and the exhaust duct (80) by receiving the measured nitrogen concentration of the internal sensor and the external sensor to adjust the oxygen concentration in the chamber (21) And a controller for warning the danger to the operator by sounding an alarm when the surrounding oxygen concentration is lowered below the level required for the operator, by sucking and removing the surrounding nitrogen to keep the operator safe.

The controller continues to supply nitrogen to the chamber 21 through the nitrogen nozzle 40 and the nitrogen knife member 50 until the oxygen concentration in the chamber 21 is below the set value and the ambient air continues to flow through the chamber 21). When the oxygen concentration in the chamber 21 becomes lower than the set value, the supply of nitrogen to the chamber 21 is stopped to prevent unnecessary waste. At this time, the nitrogen knife member 50 may intermittently discharge nitrogen when the nitrogen is supplied to the chamber 21 by interlocking with the nitrogen nozzle 40, and when the supply of nitrogen is stopped, Nitrogen may be continuously discharged regardless of the nitrogen supply of the fuel cell 40.

Although the present invention has been described with reference to the accompanying drawings, it is to be understood that the present invention is not limited thereto, and various modifications and changes thereto may be made by those skilled in the art. And should be construed as falling within the scope of protection of the present invention.

10: Drum 20: Chamber unit
21: chamber 22: upper frame
23: lower frame 24: arc frame
25: compartment frame 26: transparent plate
261: closure plate 27: mounting plate
30: UV lamp module 40: nitrogen nozzle
50: Nitrogen knife member 60: Seal panel
70: gap adjusting member 80: exhaust duct
90: housing 100: forward / backward means
110: stopper 120: pedestal

Claims (4)

A drum through which the film coated with the UV coating passes;
A chamber unit having a semi-cylindrical structure for forming a chamber surrounding the drum;
A UV lamp module for irradiating the chamber of the chamber unit with UV light;
A nitrogen nozzle for discharging nitrogen into the chamber of the chamber unit;
A nitrogen knife member disposed in both longitudinal sides of the chamber unit for discharging nitrogen to block external air from entering the chamber;
An actual panel disposed at an edge of the chamber unit and arranged in both the longitudinal direction and the both-side arc direction of the drum;
And a gap adjusting member for adjusting the gap with respect to the drum by respectively moving the yarn panels arranged in both the longitudinal direction and the both-side arc direction of the drum,

Wherein the nitrogen knife member discharges nitrogen to a portion where the film is in close contact with the drum,
The sealing panel is made of Teflon resin,
Wherein the gap adjusting member comprises: a fixing block fixedly coupled to the mounting plate of the chamber unit; an adjusting bolt screwed to the fixing block to move up and down; And a bracket for adjusting the position of the seal panel by moving up and down together with the adjustment bolt to adjust the position of the seal panel. The method according to claim 1,
The chamber unit
An upper frame and a lower frame arranged at the upper and lower sides and arranged in the longitudinal direction on the upper and lower sides of the drum,
A arc frame connected to both ends of the upper frame and the lower frame and having an arcuate shape and arranged at the outer periphery of the drum,
A plurality of compartment frames for connecting the two call frames on both sides in the longitudinal direction to form an arrangement space in which the UV lamp modules are arranged,
A plurality of transparent plates that cover the arrangement space and allow the ultraviolet rays emitted from the UV lamp module to pass therethrough while blocking inflow of outside air;
And a mounting plate mounted on the adjacent two section frames and on which the transparent plate is mounted,

The transparent plates are seated so as to be continuous with the mounting grooves formed in the periphery of the front opening of the mounting plate, and a blocking plate is disposed at a portion where the transparent plate and the transparent plate meet to cover the clearances between the transparent plates, And the pressure plate is fixed to the mounting plate so as to press the blocking plates toward the mounting plate so that the blocking plate seals the gap between the two transparent plates by the pressure of the blocking plate, And the air gap is tightly sealed with the mounting plate to block the inflow of outside air. The method according to claim 1,
Further comprising: an exhaust duct disposed in both longitudinal sides of the chamber unit for sucking and removing nitrogen flowing out of the chamber. 4. The method according to any one of claims 1 to 3,
A housing in which the chamber unit is mounted;
Forward and backward means for causing the housing to advance and retract;
Further comprising: a stopper for limiting a forward range of the housing by the forward and backward means.

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