JPH081020Y2 - Air knife for paper machine - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a papermaking coating machine for coating a paper surface with a paint or the like at the time of papermaking, and more particularly to an air knife for adjusting the coating amount of the paint coated on the paper surface by using air.

[0002]

2. Description of the Related Art As is well known, at the time of papermaking, a paint or the like is applied in order to improve the smoothness of the paper surface and the printing characteristics.
A rod coater, a blade coater, an air knife coater, etc. are generally used as the coating device. Among the coaters, the air knife coater is a color
The coating material supplied to the pan is applied to the paper surface by an applicator roll, and the coating amount is adjusted to a predetermined amount by an air knife arranged on the downstream side of the applicator roll.

[0003]

By the way, as shown in FIG. 6, the air knife is a hollow body, and lips 2, 2 are provided on the tip side of the upper and lower knives 1, 1 which are arranged facing each other.
Is attached to form the air outlet 3 in the width direction, and the air supplied to the hollow portion 4 from the air pipes connected to both side plates is discharged from the outlet, and the upper and lower knives 1, 1 A plurality of reinforcing ribs 5 are arranged in the width direction to reinforce the knife. In the air knife of the above structure, when air is supplied from the air pipes arranged on both side plates, a turbulent flow is generated at the air confluence point in the center of the knife or in the vicinity of the rib arranged for the purpose of reinforcing the knife. Discharge as it is. The air knife blows air from the outlet toward the paint applied to the paper surface.
In addition, the air is sprayed with a uniform pressure in the width direction, and the excess paint is scraped off to smooth the coated surface, but when the air is sprayed in a turbulent state as described above, Air is not jetted at a uniform pressure in the width direction, resulting in unevenness on the coated surface, so-called uneven coating. The present invention has been made to eliminate the above-mentioned conventional problems, and an object of the present invention is to provide an air knife having a simple structure and free from uneven coating.

[0004]

In order to achieve the above object, the present invention provides a papermaking coating in which the coating material applied to the paper surface by an applicator roll is adjusted to a predetermined coating amount by an air knife equipped with an air outlet. An air knife for a machine, wherein a straightening plate having a large number of through holes that open toward the air outlet is provided inside the air outlet of the air knife.
In the air knife having the above-mentioned configuration, the straightening vane is arranged inside the air blowing port, so that the air passes through the through hole of the straightening vane to form a laminar flow of the same pressure and is jetted from the blowing port to the coating surface to paint. And scrape it evenly to smooth it. Therefore, there is no coating unevenness on the coated surface.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in the drawings. FIG. 1 is a schematic side view of a paper coating machine equipped with an air knife according to an embodiment of the present invention, in which reference numeral 10 is a coating machine. The coating machine 10 is a transfer roll 11,
It consists of an applicator roll 12, a color pan 13, a metering roll 14, a breast roll 15, a catch pan 16 and an air knife 17. The running base paper P is coated with the paint filled in the color pan 13 with the applicator roll 12, and the breast is pressed. The paint is evenly sprayed and smoothed by an air knife 17 arranged on the side of the roll 15, and the excess paint blown is collected in a catch pan 16.

An air knife 1 for scraping off the excess paint
In order to prevent the line from being stopped during maintenance and maintenance of the air outlet, a pair of right and left 7 are arranged in this embodiment as shown in FIGS. 2 and 3, and are rotated by a rotating mechanism (not shown). Either the left or right air knife 17 can be selected. The structure of the air knife 17 is the same on the left and right.
Therefore, the explanation of the operation etc. is also explained with one air knife.
Only 17 will be described . That et Anaifu 17 back plate as shown in FIG. 3 18, the knife holding member 19,1
9, a hollow body having an isosceles triangular shape in cross section, which is composed of both side plates 20, 20 and lips 21, 21, and has upper and lower lips 21, 2
An air outlet 22 is formed in the width direction on the front end side of 1, and pipes 23 for air supply are attached to both side plates. As shown in FIG. 4, a reinforcing rib 25 having a predetermined span in the width direction is provided in the hollow portion 24 of the air knife 17 in order to hold and reinforce the upper and lower lips 21, 21. A rectifying plate 26 is arranged in the width direction of the outlet 22.

The current plate 26 is made of high-density polyethylene having a thickness of about 15 mm and has a large number of through holes 27 formed therein. The through holes 27 are two holes 27a having different diameters,
As shown in FIG. 5, the diameter of the hole 27a on the rib 25 side is larger than the diameter of the hole 27b on the outlet 22 side as shown in FIG.

The operation of the air knife 17 of this embodiment having the above construction will be described. The base paper P coated with the coating by the applicator roll 12 arranged in the lower stage of the transfer roll 11 is the metering roll 14 and the breast roll 1.
After passing through 5, the excess knife is removed by the air knife 17 arranged at a position facing the breast roll 15, and the surface is smoothed.

That is, the air knife 17 is always provided with the side plate 2
Air is supplied from the pipes 23, 23 attached to the Nos. 0 and 20, and the air passes from the hollow portion 24 through the through hole 27 of the flow straightening plate 26 to become a laminar flow having the same pressure and from the blowout port 22. 2 is sprayed in the direction orthogonal to the coated surface of the processed base paper P, and the paint applied to the base paper P is evenly blown to a constant thickness with a constant wind pressure, and excess paint is blown off. It is one. The paint that has been blown off is caught by the catch pan 1 provided on the lower surface of the air knife 17.
Recovered in 6.

Since the air knife of the present embodiment has the above-mentioned structure, even if turbulent flow occurs in the air supplied to the hollow portion of the air knife, the air knife passes through the through hole of the straightening vane, and the entire width direction of the outlet is Air blows out as a laminar flow of constant pressure,
Does not cause uneven coating on the coating surface .

Although the current plate 26 is made of high-density polyethylene in the above embodiment, the present invention is not limited to this, and other synthetic resins such as epoxy resin and phenol resin may be used. The through hole 27 to be provided may be a through hole in which the diameter of the hole is gradually reduced, instead of the step diffuser type.

Further, it is needless to say that the present invention is not limited to the above-mentioned embodiment, and various modifications and design changes can be made without changing the gist of the invention.

[0013]

[Effects of the Invention] The present invention is designed so that a fixed amount is provided inside the air outlet.
Attach a rectifying plate with a thickness, and
A through hole is formed and the diameter of the through hole is set to the air inlet side.
The hole diameter on the rib 25 side is different from that on the outlet side, and the outlet 2
Larger hole diameter on the 2 side, so high laminar flow formation effect
Exerts the effect. In other words, the present invention is as described above.
Since it has such a structure, the air supplied inside the air knife is
Passes through the through hole of the baffle plate,
A laminar flow of constant pressure is ejected from the width direction toward the coating surface.
However, it is possible to evenly spread the entire coated surface in the width direction.
Therefore, uneven coating does not occur. Well
Moreover , the structure is simple and the number of parts is small, so that it can be applied to the existing air knife, which is practical.

[Brief description of drawings]

FIG. 1 is a schematic side view of a coating machine equipped with an air knife according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an air knife of the present invention.

FIG. 3 is a sectional view of the air knife of the present invention.

FIG. 4 is a partially cutaway perspective view showing the inside of the air knife.

FIG. 5 is a partially cutaway perspective view showing a current plate.

FIG. 6 is a view showing a conventional air knife.

[Explanation of symbols]

 10 Coating Machine 11 Transfer Roll 12 Applicator Roll 13 Color Pan 14 Metalling Roll 15 Breast Roll 16 Catch Pan 17 Air Knife 18 Back Plate 19 Knife Holding Member 20 Side Plate 21 Lip 22 Air Blowout 23 Pipe 24 Hollow Part 25 Rib 26 Rectifier 27 Through hole

Claims (2)

[Scope of utility model registration request] 1. A paper manufacturing method in which a coating material applied to a paper surface by an applicator roll (12) is adjusted to a predetermined coating amount by an air knife (17) having an air outlet (22). A rectifying plate (26) having a constant thickness is provided in the air outlet (22) of the coating machine for the outlet .
In addition, a large number of through holes (27) are bored in the straightening vane,
The diameter of the through hole located on the side of the outlet (22)
An air knife for a paper coating machine characterized by being made smaller than the diameter . 2. The air knife for a papermaking coating machine according to claim 1, wherein the through hole provided in the current plate is a through hole having two steps (27a) and (27b) having different diameters and having a step.