JP4487435B2 - Flow linctor cleaning liquid foam prevention device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for preventing foaming of a cleaning liquid in a flow clintor used for cleaning a backing roll of a coating apparatus that uses paper manufactured in a paper mill as a raw material and applies a coating liquid on the surface thereof.
[0002]
[Prior art]
Paper manufactured at a paper mill is not immediately used as it is, and is often processed into base paper to be processed paper as a product that meets the desired purpose. There are various types of processed paper, one of which is coated paper. The coated paper is produced by applying a coating liquid (coating color) to the surface of the paper, and a coating apparatus is used as an apparatus for that purpose.
[0003]
One such coating apparatus is a blade coater as schematically shown in FIG. The blade coater is provided with a coating liquid ejecting head 3 that is a fountain that extends in parallel with the longitudinal direction of the backing roll 2 at a position near the lower side of the backing roll 2 on which the base paper 1 is wound. The excess coating liquid 4 applied to the surface of the base paper 1 is scraped off from the coating liquid ejecting head 3 at a position downstream of the coating liquid ejecting head 3 in the rotation direction of the backing roll 2. The metering blade 5 is disposed so as to be in contact with the surface of the base paper 1, and first, the coating liquid 4 is jetted and supplied from the coating liquid jet head 3 toward the surface of the base paper 1, and the width is applied to the surface of the base paper 1. The coating liquid 4 is applied uniformly in the direction, and then the surplus portion of the coating liquid 4 applied to the base paper 1 is scraped off by the metering blade 5 so that the surface of the base paper 1 has a required thickness. Uniform formation of coating liquid film Unishi to have.
[0004]
Further, as another coating apparatus provided with a backing roll, in the same configuration as the blade coater, a coating liquid supplied from the coating liquid ejecting head to the surface of the base paper by a rotating rod instead of the metering blade There are a rod coater that scrapes off the surplus part, an air knife coater that scrapes off the surplus part of the coating liquid supplied to the surface of the base paper by an air knife, and the like.
[0005]
By the way, paper powder may adhere to the backing roll of each of these coating apparatuses, or a coating liquid that has passed through the base paper or a coating liquid that has protruded from the end in the width direction of the base paper may adhere. Therefore, in the case of the blade coater shown in FIG. 3, the entire length of the backing roll 2 is generally parallel to the longitudinal direction of the backing roll 2 at a required position on the downstream side in the rotational direction from the top of the backing roll 2. A doctor body 7 having a blade 8 extending at the lower end and extending over the entire length in the longitudinal direction, and arranged so that the lower end of the blade 8 slides on the outer circumferential surface of the backing roll 2 without any gap over the entire length in the longitudinal direction. Then, a recess 9 for storing liquid is formed between the rotating backing roll 2 and the doctor body 7, and a cleaning liquid 10 such as water or warm water is supplied to the recess 9 from a cleaning liquid supply nozzle connected to a cleaning liquid supply device (not shown). At the same time, the cleaning liquid 10 that overflows in the recovery pans (not shown) installed at both ends of the backing roll 2 is recovered, A flow clincher 6 having a structure in which the cleaning liquid 10 is stored in the concave portion 9 to a predetermined level position is installed, and the surface of the backing roll 2 passing through the concave portion 9 as it rotates is accumulated in the concave portion 9. By bringing it into contact with the cleaning liquid 10, the paper powder and coating liquid adhering to the surface of the backing roll 2 can be cleaned.
[0006]
In recent years, coating apparatuses tend to be faster and wider. Of these, if the rotation of the backing roll 2 is increased in order to increase the speed, the air that is rotated by the rotating backing roll 2 is used. 11 is entrained in the cleaning liquid 10, causing a foaming phenomenon (boiling phenomenon) that generates a large amount of bubbles in the cleaning liquid 10 when boiling, and the cleaning liquid 10 and the coating liquid mixed in the cleaning liquid 10 may be scattered. In addition, the foaming phenomenon tends to cause instability such as disturbance in the contact between the blade 8 and the backing roll 2, which may cause damage to the surface of the backing roll 2 by the blade 8 and the cleaning liquid for the recess 9. 10 may leak to the downstream side of the blade 8. For this reason, conventionally, in order to prevent scattering of the liquid due to the foaming phenomenon, a cover 12 that covers the liquid surface of the cleaning liquid 10 is installed at a position slightly above the surface of the cleaning liquid 10 in the recess 9 of the doctor body 7. I was doing.
[0007]
[Problems to be solved by the invention]
However, since the cover 12 must be provided with a required gap between the cover 12 and the backing roll 2 so that the cover 12 does not come into contact with the surface of the backing roll 2 to be damaged, the cleaning liquid 10 scatters from the gap. In addition, there is a problem that the bubbling phenomenon of the cleaning liquid 10 cannot be prevented because the air 11 on the surface layer of the backing roll 2 is circulated through the gap.
[0008]
In view of this, the present invention prevents flow of cleaning liquid by preventing the foaming phenomenon of the cleaning liquid and preventing the scattering of the cleaning liquid by preventing air entrained by the backing roll from being caught in the cleaning liquid of the flow clinic. It is intended to provide a prevention device.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a doctor body having a blade at the lower end at the upper position downstream in the rotational direction from the top of the backing roll, over the entire length in parallel with the longitudinal direction of the backing roll. The surface of the backing roll is washed with the cleaning liquid collected between the backing roll and the doctor body, and is rotated by the backing roll at a position upstream of the rotating direction of the backing roll of the flow clintor. An air cut device having an air blowing nozzle formed with a flow path at a required angle with respect to the surface of the backing roll toward the upstream side in the rotational direction so as to block the air toward the flow clintor, and the air outlet of the air blowing nozzle and placed in wide over the entire length of the backing roll so that a gap between the backing roll surface is reduced A guide plate having a length over the entire length in the longitudinal direction of the backing roll and curved in the width direction along the backing roll is provided at the downstream end of the air cut device in the rotational direction of the backing roll. A configuration in which the gap between the curved inner surface of the plate and the surface of the backing roll is arranged to be small, and the downstream end of the guide plate is immersed in the cleaning liquid stored in the flow clintor And
[0010]
The air that is rotated along with the rotation of the backing roll is pushed back by the air blown from the air blowing nozzle of the air cut device toward the upstream side in the rotating direction of the backing roll. Since it is cut at the position, the bubbling phenomenon of the cleaning liquid in the recess is eliminated, and the splashing of the liquid is prevented.
[0011]
Further, a guide plate having a length over the entire length in the longitudinal direction of the backing roll and curved in the width direction along the backing roll is provided at the downstream end of the air cut device in the rotational direction of the backing roll. and by the gap between the backing roll surface are a configuration in which mounting and arranged to be smaller, the space between the guide plate and the backing roll surface located on the backing roll rotation direction downstream of the air outlet, Ki out that the static pressure area by ejector effect, the air being brought fucked can be prevented the risk that another air is disturbed, it is possible to improve the effect of preventing bubbling of the cleaning liquid.
[0012]
Furthermore, by providing the downstream end of the guide plate so as to reach the cleaning liquid in the recess of the flow clintor, it is possible to more effectively prevent air from entering the cleaning liquid in the recess.
[0013]
Further, the air blowing nozzle is blown out to the upstream side in the rotating direction of the backing roll of the air blowing nozzle of the air cut device to which the downstream end of the cleaning liquid stored in the flow clincher is attached. And a suction box for collecting the air of the backing roll surface layer pushed back by the air, the air blown from the air blowing nozzle stays in the vicinity of the air blowing nozzle. It is possible to prevent the possibility of affecting the cleaning liquid of the flow clintor.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
FIG. 1 shows one embodiment of the apparatus for preventing foaming of a washing liquid flow cleaner of the present invention. Similar to that shown in FIG. 3, the upper required position on the downstream side in the rotational direction from the top of the backing roll 2 In addition, a doctor body 7 having a blade 8 is arranged at the lower end, and the cleaning liquid 10 is accumulated in a recess 9 formed between the surface of the rotating backing roll 2 and the doctor body 7 to a predetermined level position. In the configuration in which the flow clintor 6 is installed so as to clean the surface of the backing roll 2, the upstream side of the backing roll 2 in the rotational direction of the backing roll 2 with respect to the surface of the backing roll 2. An air cut device 13 having an air blowing nozzle 14 having a flow path inclined at a required angle toward the upstream side in the rotation direction is The air outlet 14a of the attaching nozzle 14 is installed as a wide width over the entire length in the longitudinal direction of the backing roll 2 so that the gap becomes small by approaching the surface of the backing roll 2, and is shown in the air blowing nozzle 14. The air 15 is connected to the backing roll 2 and connected to the flow roll doctor 6. The air 15 is counter-flowed to the air flow 11. The surface of the backing roll 2 is blown from the outlet 14 a of the air blowing nozzle 14. It is set as the structure which sprayed on.
[0016]
Further, at the downstream end of the air cut device 13 in the rotational direction of the backing roll 2, as shown in FIG. 1, the backing roll 2 has a length over the entire length in the longitudinal direction and the outer circumference of the backing roll 2 in the width direction. Attaching one end of the guide plate 16 in the width direction that is curved along the guide plate 16, and so that the inner side surface in the curve direction of the guide plate 16 approaches the surface of the backing roll 2 so that the gap is reduced, A static pressure region can be formed between the guide plate 16 and the surface of the backing roll 2 by an ejector effect generated when the air 15 is blown from the air blowing nozzle 14 toward the upstream side in the rotation direction of the backing roll 2. Like that.
[0017]
Further, as shown in the drawing, a suction box 17 extending over the entire length of the backing roll 2 in the longitudinal direction is provided on the upstream side of the air blowing nozzle 14 of the air cut device 13 in the rotational direction of the backing roll 2. Further, the air 15 blown to the surface of the backing roll 2 and the air 11 circulated by the backing roll 2 can be sucked.
[0018]
The angle of the air outlet 14a of the air blowing nozzle 14, that is, the angle formed with respect to the surface of the backing roll 2, is a blowing angle that can cut the air 11 that is carried by the backing roll 2. For this purpose, an angle larger than a certain angle is necessary, for example, about 3 to 30 degrees.
[0019]
When the coating apparatus is in operation, a constant level of the cleaning liquid 10 is always accumulated in the recess 9 of the flow clintor 6, so that the surface of the backing roll 2 continuously moves as the backing roll 2 rotates. Cleaning is performed by passing through the recess 9 of the flow clintor 6 and being brought into contact with the cleaning liquid 10. When the surface of the backing roll 2 is cleaned, the air 15 led to the air blowing nozzle 14 from the air supply source is blocked in order to block the air 11 that is rotated by the rotating backing roll 2 from reaching the flow clean doctor 6. With respect to the surface of the backing roll 2 from the blower outlet 14a, it is made to blow off diagonally toward the upstream side. At this time, the flow rate of the air 15 blown out from the air outlet 14 a of the air blowing nozzle 14 along the surface of the backing roll 2 is made larger than the flow rate of the air 11 rotated along with the rotation of the backing roll 2. Specifically, by increasing the peripheral speed of the backing roll 2 by 20 to 50%, the air 11 circulated by the backing roll 2 passes through the position of the suction box 17 and blows air. When it comes to the position of the nozzle 14, it is pushed back by the air 15 blown out from the outlet 14 a of the air blowing nozzle 14 toward the upstream side in the rotation direction of the backing roll 2, and pushed back in the direction of the suction box 17. It will be made to flow backward. Thereby, the air 11 of the surface layer of the backing roll 2 is cut at the position of the air outlet 14 a of the air blowing nozzle 14.
[0020]
Further, the guide plate 16 is attached to the downstream end of the air cut device 13 in the direction of rotation of the backing roll 2 so that the backing roll 2 rotates more than the air outlet 14a by the air 15 blown out from the air outlet 14a. Between the guide plate 16 located on the downstream side in the direction and the surface of the backing roll 2, a static pressure region is caused by the ejector effect, and there is no turbulence of air different from the air 11 to be rotated, and the wind speed becomes zero.
[0021]
Next, FIG. 2 shows another embodiment of the present invention. The guide plate 16 in the embodiment shown in FIG. 1 has a downstream end that is the free end in the width direction. 6 is configured to be extended so as to be immersed in the cleaning liquid 10 accumulated in the recess 9.
[0022]
According to this embodiment, since the other end of the guide plate 16 is made to be immersed in the cleaning liquid 10 accumulated in the recess 9 of the flow clintor 6, the air outlet 14 a and the flow clintor 6 Since no air is newly brought to the backing roll 2 between the air, the air is not involved in the cleaning liquid 10 of the flow clintor 6 and the occurrence of foaming phenomenon can be prevented and the scattering of the liquid can be prevented. The
[0023]
In each of the above embodiments, the air 15 blown out from the air blowing nozzle 14 and the air 11 in the surface layer of the backing roll 2 pushed back to the suction box 17 side by the air 15 are sucked into the suction box 17. And recovered. For this reason, the possibility that the air 15 blown out from the air blowing nozzle 14 stays in the vicinity of the air blowing nozzle 14 and affects the cleaning liquid 10 of the flow clintor 6 can be prevented.
[0024]
In addition, this invention is not limited only to said each embodiment, It can apply to the flow clintor 6 attached to the backing roll 2 of various coating machines, such as a blade coater, a rod coater, an air knife coater, etc. Of course, various modifications can be made without departing from the scope of the present invention.
[0025]
【The invention's effect】
As described above, according to the cleaning liquid foam preventing device of the flow clintor of the present invention, the doctor body having the blade at the lower end is disposed at the upper position downstream of the top of the backing roll in the rotational direction. An upstream position in the direction of rotation of the backing roll of the flow clintor, which is arranged over the entire length in parallel with the longitudinal direction and which cleans the surface of the backing roll with the cleaning liquid accumulated between the backing roll and the doctor body. In addition, an air cut device having an air blowing nozzle that forms a flow path at a required angle with respect to the surface of the backing roll toward the upstream side in the rotational direction so as to block the air directed to the flow clintor by being rotated by the backing roll, The clearance between the air blowing nozzle outlet and the backing roll surface is reduced. Tsu installed in wide over the entire length of the king roll, and, to the backing roll rotation direction downstream side end portion of said air-cut device, along the backing roll and the width direction has a length over the longitudinal direction of the length of the backing roll The guide plate is bent and arranged so that a gap between the inner side surface of the guide plate in the bending direction and the surface of the backing roll is reduced, and the downstream end of the guide plate is attached to the flow clintor. Because it is configured to be immersed in the cleaning liquid stored in the air, the air that is circulated on the surface of the backing roll can be pushed back to the upstream side in the rotation direction of the backing roll without contact, and the air can be cut. Air no longer gets caught in the cleaning fluid of the clintor, preventing the foaming phenomenon of the cleaning fluid, Scattering can be prevented, also the backing roll rotation direction downstream side end portion of said air-cut device, is curved along the backing roll and the width direction has a length over the longitudinal direction of the length of the backing roll and the guide plate, by the gap between the bending direction in the side surface and the backing roll surface are a configuration in which mounting and arranged to become smaller, the guide plate positioned backing roll rotation direction downstream of the outlet Between the surface and the backing roll surface can be made a static pressure region by the ejector effect, and it is possible to prevent the turbulence of the air different from the air that is rotated by the rotating backing roll, preventing the foaming of the cleaning liquid It can be improved, further, as a structure in which immerses downstream end of the guide plate in a cleaning solution flow Klin doctor Therefore , it is possible to more effectively prevent the inflow of air into the cleaning liquid. In addition, the air blowing device is equipped with a guide plate with the downstream end immersed in the cleaning liquid stored in the flow clintor. By providing a suction box for collecting the air blown from the air blowing nozzle and the air of the backing roll surface layer pushed back by the air on the upstream side of the nozzle's backing roll rotation direction, air blowing An excellent effect is exhibited such that air blown out from the nozzle can be prevented from staying in the vicinity of the air blowing nozzle and affecting the cleaning liquid of the flow clintor.
[Brief description of the drawings]
FIG. 1 is a partially cut schematic side view showing an embodiment of a washing liquid foaming prevention device for a flow clintor of the present invention.
FIG. 2 is a partially cut schematic side view showing another embodiment of the present invention.
FIG. 3 is a side view schematically showing an example of a coating apparatus.
[Explanation of symbols]
2 Backing roll 6 Flow clintor 7 Doctor body 8 Blade 9 Recess 10 Cleaning liquid 11 Air 13 Air cut device 14 Air blowing nozzle 14a Air outlet 15 Air 16 Guide plate 17 Suction box

Claims (2)

At the upper position downstream of the top of the backing roll in the rotational direction, a doctor body provided with a blade at the lower end is disposed over the entire length in parallel with the longitudinal direction of the backing roll, and the backing roll and the doctor body The surface of the backing roll is cleaned with the cleaning liquid collected during the period of rotation, and is rotated so as to shut off the air that is rotated by the backing roll and directed to the flow clintor at the upstream side of the backing roll rotation direction. An air cut device having an air blowing nozzle in which a flow path is formed at a required angle with respect to the surface of the backing roll toward the upstream side in the direction so that a gap between the air outlet of the air blowing nozzle and the surface of the backing roll is reduced. installed in wide over the entire length of the backing roll, and, aeration of the air cut-off device A guide plate having a length extending over the entire length in the longitudinal direction of the backing roll and curved along the backing roll in the width direction at the downstream end in the roll rotation direction, A flow characterized by having a structure in which a gap between the surface of the backing roll is arranged to be small, and the downstream end of the guide plate is immersed in a cleaning liquid stored in the flow clintor. Cleaner foam prevention device for clintor. The air blown from the air blowing nozzle on the upstream side in the backing roll rotation direction of the air blowing nozzle of the air cut device in which the guide plate with the downstream end immersed in the cleaning liquid stored in the flow clintor is attached, and flow Clean doctor cleaning liquid foaming prevention apparatus according to claim 1, wherein is provided a suction box for collecting the air backing roll surface layer is pushed back by the air.

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