JPH05269452A - Dust removing apparatus for sheet-like item - Google Patents

Abstract

PURPOSE:To float efficiently stuck dust and to make it possible to suck the floated dust in a suction box without leakage outside by making ejected air from a nozzle to come effectively into collision with the surface of a sheet-like item. CONSTITUTION:A dust removing apparatus for a sheet-like item wherein a nozzle 15 and a suction box 16 are provided and the angle of air ejection of the nozzle 15 is 65 or smaller to the face of the sheet-like item and the distance between the nozzle 15 and an opening part 17 of the suction box is at least 30mm and the face being in parallel to the sheet-like item adjoining to the nozzle 15 is extended to the upstream side of the nozzle by at least 15mm and to the downstream side by at least 5mm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust removing device which is applied to a sheet-like material manufacturing apparatus or processing apparatus such as film or paper and removes dust adhering to the surface of the sheet-like material from a running sheet-like object. ..

[0002]

2. Description of the Related Art A device for manufacturing or processing a sheet material such as a film is provided with a dust removing device for removing dust adhering to the surface of the traveling sheet material (for example, cutting powder of the sheet material in a slitting process). May be Since the dust is removed from the surface of the sheet material while it is running, it is desirable to use the non-contact method. Conventionally, air is ejected at high speed toward the surface of the sheet material, and dust adhering to the surface of the sheet material is ejected. There is known a dust remover that floats with air and sucks and removes dust with air jetting (for example, JP-A-58-159883 and JP-A-1-284).
No. 376).

Such a conventional dust removing device is constructed, for example, as shown in FIG. In the illustrated example, the dust removing device 1 is arranged on the guide roll 3 that conveys the sheet-shaped material 2 with a space provided between the sheet-shaped material 2 that is conveyed. The dust removing device 1 is provided with a nozzle 4 that ejects air at a high speed in a direction opposite to the traveling direction of the sheet-like material 2, and a suction box 5 that sucks air. The air ejected from the nozzle 4 is struck on the surface of the sheet-like material 2, and the dust adhering to the surface of the sheet-like material 2 is suspended. The suspended dust is sucked into the suction box 5 together with the jet air, and is removed from the surface of the sheet-like material 2. This prevents foreign matter from entering the product sheet.

[0004]

In the conventional device as described above, dust suspended from the surface of the sheet-like material 2 is
If the air leaks to the outside from between the dust removing device 1 and the sheet-like material 2 together with the jet air, the suspended dust may adhere to the surface of the sheet-like material 2 again. Therefore, it is desirable that the dust once suspended be sucked into the suction box 5 as much as possible (desirably the whole dust). To this end, the negative pressure in the suction box 5 is increased, and in addition to the air suction from the nozzle 4, air in the atmosphere is slightly sucked through between the dust removing device 1 and the sheet-like material 2. preferable.

However, if the relationship between the air jet from the nozzle 4 and the air suction (negative pressure) by the suction box 5 is set to the above-mentioned relation, the air jetted from the nozzle 4 collides with the surface of the sheet-like material 2. Will slow down,
The ability to float dust from the surface of the sheet is reduced.
In an extreme case, the air blown out from the nozzle 4 does not collide with the surface of the sheet-like object 2 at all, and a short circuit occurs, so that the suction box 5 is directly connected.
In some cases, the dust is not sucked into the body and the dust floating effect is not achieved. In such a case, the suction box 5 is unavoidable.
The negative pressure (suction force) of the nozzle 4 is reduced to allow a part of the air blown from the nozzle 4 to leak outside between the dust removing device 1 and the sheet-like material 2 (for example, to the downstream side in the sheet-like material traveling direction). However, in this case, once suspended dust adheres to the surface of the sheet-like material 2 again on the downstream side of the dust removing device 1, for example, and the dust removing effect is significantly reduced.

Further, by reducing the air ejection angle of the nozzle 4 with respect to the sheet-like material 2, it is possible to reduce the air leakage to the downstream side of the sheet-like material traveling direction. The collision speed of the sheet 2 with the sheet-like material 2 decreases, the performance of floating the adhered dust decreases, and the dust removal performance decreases.

The present invention pays attention to the problems in such a conventional device, and more effectively causes the air blown from the nozzle to collide with the surface of the sheet-like material to efficiently float the attached dust from the surface of the sheet-like material. An object of the present invention is to provide an air blowing type dust remover for sheet-like objects, which efficiently sucks suspended dust into the suction box without leaking to the outside.

[0008]

Means for Solving the Problems A sheet-shaped object dust removing device according to the present invention, which is directed to the above object, is arranged at a distance from a running sheet-shaped object, and is provided on a surface facing the sheet-shaped object. It has a nozzle for ejecting air toward the sheet-like material and a suction box for sucking air from the direction of the sheet-like material, and the suction box is arranged on the upstream side in the sheet-like material traveling direction and the nozzle is arranged on the downstream side. In the above dust removing device for sheet material, the air ejection angle of the nozzle is set to 65 relative to the surface of the sheet material in the direction opposite to the sheet running direction.
The angle is less than or equal to 30 degrees, the nozzle and the opening of the suction box are arranged at a distance of 30 mm or more in the sheet running direction, and a surface facing the sheet and parallel to the surface of the sheet is provided. Adjacent to the nozzle, it extends 15 mm or more toward the upstream side in the sheet running direction and 5 mm or more toward the downstream side.

In the above dust removing device, the relationship between the width of the nozzle and the width of the suction box is not particularly limited, but it is preferable that the width is substantially the same. Further, adjacent to the nozzle on the surface facing the sheet-like material, the width of the portion parallel to the surface of the sheet-like material provided on the upstream side and the downstream side of the sheet-like material traveling direction is at least that of the nozzle. It is preferably the same as the width, and preferably larger than the nozzle width.

[0010]

In the sheet dust removing device,
As shown in the results of each of the examples described below, in a practical air ejection velocity range, the air ejection angle from the nozzle, the size of the surface parallel to the sheet-like material on the upstream side and the downstream side of the nozzle in the sheet-like material traveling direction. By optimizing the height, the air blown out from the nozzle collides with the surface of the sheet-like object along with the dust suspended even when no negative pressure is applied to the suction box. ). Therefore, the jetted air and the suspended dust are not leaked to the downstream side of the dust removing device. Further, by providing the nozzle and the suction box opening at a certain distance or more, even if the negative pressure of the suction box is increased, a large negative pressure does not reach the air ejection portion of the nozzle, and the air ejected from the nozzle is in the form of a sheet. It is possible to prevent a short circuit such as being sucked into the suction box without hitting an object and a decrease in the air velocity that collides with a sheet-like object, and it is possible to smoothly collect all ejected air and suspended dust in the suction box without leaking it to the outside. Therefore, it is possible to prevent the dust suspended by the air blown from the nozzle from adhering again to the surface of the sheet-like material.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a dust remover for sheet material according to an embodiment of the present invention, in which the present invention is applied to a slitter for cutting a plastic film into a desired width. In FIG. 1, reference numeral 11 denotes a plastic film (for example, a biaxially stretched film) after slitting as a sheet-shaped material. After the slit,
Cutting chips adhere to the surface of the film 11. On the guide roll 12 that conveys the film 11, the conveying film 1
The dust removing device 13 is installed at a distance from the position 1.

In the dust removing device 13, a nozzle 15 for ejecting air from the pressure chamber 14 toward the film 11 and an opening of a suction box 16 for sucking air from the direction of the film 11 are provided on the surface facing the film 11. 17 are provided. In this embodiment, the nozzle 15 is opened in a direction that opposes the film traveling direction and ejects air at an ejection angle θ of 60 degrees with respect to the film surface, and continuously extends over the entire length in the width direction. .. It should be noted that the air ejection angle θ is the nozzle tangent to the tangent formed downstream from the ejection point among the tangents L passing through the collision point O of the air ejected from the nozzle on the film surface on the guide roll as described above. The air ejection angle. An opening 17 of the suction box 16 is opened in a direction in which air is sucked obliquely upward from the direction of the film 11 in the direction opposite to the film running direction. The width of the suction box 16 and its opening 17 is set to be the same as the nozzle width in this embodiment. Clean air that has passed through the filter 18 is pumped into the pressure chamber 14 by the blower 19,
It is ejected from inside the pressure chamber 14 through the nozzle 15 toward the film 11. The air sucked through the opening 17 is
The suction box 16 is sucked by the blower 21 through the filter 20 and is discharged to the outside. However, for supplying and sucking air, other means such as a compressed air source or a vacuum source in a factory may be used. Also, blower 19 and blower 2
One of the two may be omitted and one unit may be recycled.

The air ejection angle θ of the nozzle 15 of the dust removing device 13 is set to 65 degrees or less with respect to the surface of the film 11 in the direction opposite to the running direction of the film 11. On the surface of the dust removing device 13 facing the film 11, the portions (surfaces) 22 and 23 parallel to the surface of the film 11 are provided with the nozzle 15
Adjacent to the film 11 and extending toward the upstream side and the downstream side in the traveling direction of the film 11, and the length thereof is 15 mm or more as the upstream side dimension l ₁ of the nozzle 15 and 5 mm or more as the downstream side dimension l ₂ of the nozzle 15. Is set to be

In such a dust removing device 13, as shown in FIG.
As indicated by the arrow, the air ejected from the nozzle 15 collides with the surface of the film 11, and thereafter all the ejected air tries to flow toward the upstream side of the film 11, so that the suction box 16 naturally comes out. Flowing toward the opening 17 of the. Therefore, by applying an appropriate negative pressure to the suction box 16, the jet air and the floating dust are
All are collected smoothly and efficiently without leaking to the outside.

At the same time, the distance l ₃ between the nozzle 15 and the opening 17 of the suction box 16 is set at a distance of 30 mm or more, so that the negative pressure applied to the suction box 16 is within the above practical air ejection velocity range. The influence of the pressure can be made to hardly affect the air ejection portion of the nozzle 15, and the reduction of the collision speed of the ejection air from the nozzle 15 to the film 11 can be suppressed, and the ejection air can be made to collide with the film 11. Instead, it is prevented from short-circuiting and flowing to the suction box 16.

As described above, by optimizing the size of each part, the air blown out from the nozzle 15 collides with the surface of the film 11 as desired, and the air and suspended dust are sucked into the suction box 16 with good efficiency. To be done. Further, even if the distance between the dust removing device 13 and the film 11 is made a little large, the above performance can be maintained. Therefore, by increasing the distance, even if the device is wide, the dust removing device 13 and the film 11 or The risk of contact with the roll 12 can be eliminated, and a more practical and safe device can be realized.

Hereinafter, more specific embodiments will be described in comparison with the prior art. Example 1 A dust removing test was performed on a guide roll of a biaxially stretched film after slitting in a slitter, using a dust remover equivalent to that shown in FIG. The test condition is that the film has a width of 1 m and a thickness of 14 μm, the film traveling speed is 400 m / min, the nozzle blowing angle is 60 degrees in the direction opposite to the film traveling direction, and the suction box opening is 50m upstream from the nozzle to the film
The positions were separated by m, and the opening suction angle was 45 degrees with respect to the film surface. The width of the nozzle and the suction box opening is 1 m, the slit gap of the nozzle (opening length in the film running direction) is 0.8 mm, and the slit gap of the suction box opening (opening length in the film running direction) is 10 mm. did. Further, on the surface facing the film, a portion parallel to the film surface is adjacent to the nozzle and is 20 mm upstream in the film traveling direction and 10 mm downstream in the film traveling direction.
The width of each nozzle is the same as the width of the nozzle. Air jet speed V of the nozzle is 120m / sec, 3m from the film
The dust remover 13 was installed at a position m away from the film, and the dynamic pressure immediately before the film collided was measured and calculated to be 100 mm.
It was found to be colliding with the film at a speed of / sec. For each of the case where the dust remover was activated and the case where it was not activated, sampling was performed for a film length of 300 m, each sample was immersed in ultrapure water and ultrasonically cleaned, and the water was applied to a particle counter, The size of dust mixed in and the number of dust of each size were measured. As a result, when the dust removing device is operated, it is 70
%, And it was confirmed that it was reduced by 90% with dust having a size of 25.1 to 50 μm.

Example 2 Under the conditions of Example 1, when the air jet velocity V from the nozzle was set to 80 m / sec, the jet velocity of the jet air to the film was 60 m / sec. As a result, when the dust remover is activated, it is 0.1-2 as compared to when it is not activated.
It was confirmed that the dust with a size of 5 μm decreased by 40% and the dust with a size of 25.1-50 μm decreased by 60%. Therefore, it is understood that the practical range of the air ejection velocity V from the nozzle is at least 80 m / sec, preferably 100 m / sec or more.

Example 3 Under the conditions of Example 1, when the air jet velocity V from the nozzle was increased to 160 m / sec, the jet velocity of the jet air to the film was 130 m / sec. As a result, when the dust removing device is operated, it is 0.
80% for dust with a size of 1 to 25 μm, 25.1 to 50
It was confirmed that dust with a size of μm reduced 95%. Therefore, although the dust removal rate was slightly improved, it can be seen that the air ejection rate from the nozzle need only be above a certain level and a sufficient removal rate can be obtained.

Example 4 When the distance l ₃ between the nozzle and the opening of the suction box was set to 80 mm in comparison with the conditions of Example 1, the collision speed of the air blown from the nozzle with the film did not change, and the dust The removal rate did not change either. Therefore, 50 is sufficient for l ₃ , and it is considered that 30 mm or more is sufficient from the comparison with Comparative Example 1 described later.

Comparative Example 1 Under the conditions of Example 1, when the distance l ₃ between the nozzle and the opening of the suction box was set to 20 mm, the suction box was prevented from leaking air between the dust remover and the film. Although the negative pressure of No. 1 was adjusted, the collision speed of the ejected air on the film was reduced to 50 m / sec. Similar to Example 1, as a result of sampling the case where the dust remover was activated and the case where it was not activated, as a result, when the dust remover was activated, compared with the case where it was not activated, the amount of dust was 0.1 to 25 μm. %, With dust having a size of 25.1 to 50 μm, there was only a 50% reduction. Therefore, l
_When the dimension of ₃ is less than 30 mm, it is considered that a part of the air blown from the nozzle is short-circuited to the suction box, and the dust floating effect and dust removal effect cannot be fully exerted.

Comparative Example 2 Under the conditions of Example 1, a negative pressure applied to the suction box was applied when tested with an apparatus in which the air ejection angle of the nozzle was 75 degrees with respect to the film surface in the direction opposite to the film running direction. Under the same conditions as in Example 1, the air leaked from the downstream side of the dust remover leaked. For this reason, the dust that has been suspended will leak to the outside of the dust remover together with the ejected air and adhere to the film surface again.To prevent this, increase the suction box negative pressure and balance the air leak-free state. .. When the dynamic pressure is measured in this state, the air ejected from the nozzle at 120 m / sec is 3 m.
It was found to collide with the film surface at a distance of m at 30 m / sec. As a result of performing a dust removal test in this state, when the dust removal apparatus is operated, it is 10% with dust having a size of 0.1 to 25 μm and 25.
Dust size of 1 to 50 μm reduced only 25%. Therefore, it can be seen that when the air ejection angle of the nozzle becomes large, that is, when it exceeds 65 degrees, the dust removal performance sharply deteriorates.

COMPARATIVE EXAMPLE 3 Under the conditions of Example 1, the film was run at a dimension l ₂ of a part downstream of the nozzle in the film running direction from the nozzle in a part parallel to the film surface provided adjacent to the nozzle on the surface facing the film. In the case where the test was conducted with an apparatus having a direction of 1 mm, when the negative pressure applied to the suction box was set to the same condition as in Example 1, leakage of jet air occurred downstream of the dust removing apparatus.
For this reason, dust that has been suspended will leak to the outside of the dust remover together with the jet air and adhere to the film surface again.To prevent this, increase the negative pressure in the suction box and balance the air to prevent air leakage. It was When dynamic pressure measurement is performed in this state, 120m from the nozzle
The air blown out at the speed of 3 / s is 3 on the film surface 3 mm away.
It was found that the vehicle collided at 5 m / sec. As a result of performing the dust removal test in this state, if the dust removal device is activated,
Compared to the case where it was not operated, the dust with a size of 0.1 to 25 μm decreased by 10%, and the dust with a size of 25.1 to 50 μm decreased only by 30%. Therefore, the dimension l
It can be seen that if ₂ is made too small, the dust removal performance deteriorates sharply, and l ₂ needs to be at least about 5 mm.

Comparative Example 4 Under the conditions of Example 1, the film traveled at a dimension l ₁ of a portion upstream of the nozzle in the film traveling direction from the nozzle in a portion parallel to the film surface provided adjacent to the nozzle on the surface facing the film. When tested with a device having a direction of 12 mm, when the negative pressure applied to the suction box was the same as in Example 1, leakage of jet air occurred downstream of the dust removing device. For this reason, dust that has been suspended will leak to the outside of the dust remover together with the jet air and adhere to the film surface again.To prevent this, increase the negative pressure in the suction box and balance the air to prevent air leakage. It was When the dynamic pressure is measured in this state, the air ejected from the nozzle at 120 m / s is 40 m / s on the film surface 3 mm away.
It turned out to be a collision in seconds. As a result of performing the dust removal test in this state, when the dust removal device is operated, compared with the case where the dust removal device is not operated, dust with a size of 0.1 to 25 μm is 15%, and a size of 25.1 to 50 μm. 35 of dust
Only%. Therefore, it can be seen that if the dimension l ₁ is made too small, the dust removal performance deteriorates sharply, and that l ₁ needs to be at least about 15 mm.

Comparative Example 5 In comparison with the conditions of Comparative Example 4, only the distance between the dust removing device and the film was changed from 3 mm to 0.5 mm, and the negative pressure applied to the suction box was set to the same negative pressure as in Example 1 to prevent air leakage. Balanced. When dynamic pressure measurement is carried out in this state, the air ejected from the nozzle at 120 m / sec has a pressure of 0.
It was found that the film surface collided at a distance of 5 mm at 100 m / sec. As a result of performing a dust removal test in this state,
When the dust remover is activated, compared with the case where it is not activated, the dust with a size of 0.1 to 25 μm is 65%, 2
It was found that the dust with a size of 5.1 to 50 μm reduced 90%, and it was found that the dust removal performance was equivalent to that of Example 1. However, the distance between the dust remover and the film is 0.5m.
In the case of production equipment, the film may be wound around the film guide roll portion in the case of production equipment. At present, the film is wound at a speed of 300 m / min or more, and the winding amount is large. In the meantime, multiple layers of film are caught, and it takes time to restore the device. Further, in a severe case, the pinched film may apply an unreasonable force to the guide roll and the dust removing device, which may damage the device. Therefore, it is difficult to actually use the gap size as in Comparative Example 5 in the production apparatus.

The results of Examples 1 to 4 and Comparative Examples 1 to 5 are summarized in Table 1.

[0027]

[Table 1]

The preferable range of the present invention will be considered as follows while considering the results of Examples and Comparative Examples in Table 1. The sheet-like material conveying speed is not particularly limited, but is preferably 1 to 1000 m / min, more preferably 1 to 50 m.
The thickness of the sheet-like material is not particularly limited, but is preferably 0.5 to 5 mm, more preferably 1 μm to 2 m.
m, the distance between the sheet and the dust remover is preferably 0.5
-15 mm, more preferably 2-10 mm. The width of the nozzle and suction box is 10-60
00 mm is preferable, and more preferably 100 to 4000.
mm. The gap between the nozzles is preferably 0.1 to 5 mm, more preferably 0.5 to 1.5 mm. The blowing angle of the nozzle needs to be 65 degrees or less, and preferably 45 to 60 degrees, with respect to the surface of the sheet-shaped material in the direction opposite to the traveling direction of the sheet-shaped material. The distance in the sheet running direction from the nozzle to the suction box opening is
(L ₃ ) is preferably 30 mm to 300 mm, more preferably 30 mm to 100 mm. The gap between the suction box openings is preferably 2 to 100 mm, more preferably 5 to 30 mm. The suction angle of the suction box opening is preferably 5 to 90 degrees with respect to the surface of the sheet-like material, and more preferably 30 to 60 degrees. Further, in a portion parallel to the surface of the sheet-like object provided adjacent to the nozzle on the surface facing the sheet-like object, the upstream side (l ₁ ) in the sheet-like object traveling direction from the nozzle is preferably 15 to 200 mm, and more preferably 20 to 100 mm, the downstream side (l ₂ )
Is preferably 5 to 100 mm, more preferably 10 to
It is 50 mm. The l ₁ to l ₃ is may be l ₁ = l ₃ if they meet a predetermined dimensional relationship.

[0029]

As described above, according to the dust remover for sheet material of the present invention, the air ejection angle of the nozzle is 65 degrees or less with respect to the surface of the sheet material in the direction opposite to the sheet running direction. At an angle of 15 mm or more to the upstream side in the sheet running direction and 5 m to the downstream side in the traveling direction of the sheet adjacent to the nozzle.
By providing m or more and separating the nozzle and the suction box opening by 30 mm or more in the sheet running direction,
It is possible to prevent the collision speed of the air blown from the nozzle from colliding with the surface of the sheet-like material, and to prevent the jetting air from short-circuiting to the suction box. Can be suspended. Further, since the negative pressure of the suction box can be increased, the suspended dust can be strongly sucked without causing a problem, and the suspended dust can be prevented from adhering to the surface of the sheet again. .. As a result, the dust removing performance of the dust removing device can be significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of a dust remover for a sheet-like object according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a conventional dust removing device.

[Explanation of symbols]

11 Film as sheet material 12 Guide roll 13 Dust remover 14 Pressure chamber 15 Nozzle 16 Suction box 17 Suction box opening 22 Part parallel to the surface of the sheet (upstream of the nozzle) 23 Parallel to the surface of the sheet Part (downstream from nozzle) l ₁ Length of part parallel to sheet surface (upstream side from nozzle) l ₂ Length of part parallel to sheet surface (downstream from nozzle) l ₃ Distance from nozzle to suction box opening

Claims (2)

[Claims] 1. A nozzle, which is arranged at a distance from a running sheet-like object, ejects air toward the sheet-like object on a surface facing the sheet-like object, and from a direction of the sheet-like object. A suction box for sucking air, the suction box on the upstream side in the sheet running direction, the dust removing apparatus for a sheet-shaped article having the nozzle disposed on the downstream side, the air ejection angle of the nozzle, the sheet-shaped The nozzle and the opening of the suction box are arranged at an angle of 65 degrees or less with respect to the surface of the sheet-like object in the direction opposite to the object-running direction, and the nozzle and the opening of the suction box are arranged at a distance of 30 mm or more in the sheet-like object running direction. The surface facing the object and parallel to the surface of the sheet-like object is adjacent to the nozzle, and is 15 mm or more toward the upstream side in the sheet-like material traveling direction and 5 m toward the downstream side.
A dust remover for sheet-like objects, which is extended by m or more. 2. The dust remover for a sheet-like object according to claim 1, wherein the dust remover is provided on a sheet-like article conveying roll.