JPS59357A - Transfer apparatus of coater - Google Patents

Abstract

PURPOSE:To attain to stabilize the flow of a liquid, by a method wherein the leading end of a nozzle supplying a coating liquid between an upper side roll and a lower side roll having base paper trained therearound is arranged in a direction crossing the line connecting the centers of two rolls at right angles and an overflow port is further provided. CONSTITUTION:A coating liquid is supplied between an upper side packing roll 2 and a lower side applicator roll 4 having base paper 1 trained thereover from the leading end part of a liquid supply nozzle 7. The upper side plate 7a forming the leading end of the aforementioned nozzle 7 is arranged almost at right angles with respect to the line connecting the centers of two rolls 2, 4 and an overflow port 8 is provided below the vicinity of the outlet of the nozzle 7. By this structure, the main stream A-B of the coating liquid smoothly enters the nip part of two rolls 2, 4 and the whole flow thereof is stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows seven examples of conventional paper coaters. (1) is a base paper, which runs in the direction of the arrow in contact with a packing roll (2). (3) is a liquid supply nozzle, which has the function of supplying the coating liquid between the base paper (1) and the applicator roll (gear). The applicator roll (1, t) rotates at a peripheral speed slower than the packing roll (2) while keeping a small gap between it and the banking roll (2), and applies the coating liquid to the base paper (
1) Create the pressure necessary to transfer.

Furthermore, by adjusting the circumferential speed and gap of the applicator roll (da), the amount of coating liquid transferred and the coating quality can be controlled. (5) is a coating liquid scraping blade that controls the final coating thickness, and (6) is a saucer for collecting the coating liquid.

However, in the apparatus shown in Fig. 1, the coating liquid is splashed backwards (inlet side) from between the λ rolls (λ) (ge), and the coating liquid is completely sprayed in the form of bands or dots on the base paper (1). There was a drawback that some parts (skips) were not adhered to.

The disadvantages of the device shown in Fig. 1 are shown in Fig. 3 (to explain in detail, the following can generally be said. (S times to /θ times), most of the coating liquid flows along the packing roll (2).

(b) Packing roll (
2) Backflow part E is located closer to the applicator roll.
exists.

(c) The larger the length 11 of the first half of the nip, the smaller the pressure gradient at the inlet.

For this reason, the conventional type has the disadvantage that the above-mentioned splash and skip occur due to the following reason.

That is, the overflow runs in the opposite direction at high speed (1
), the flow is unstable and scatters (splash).

Furthermore, since there is nothing blocking the reverse flow direction (E→F) in the reverse flow section E, as the circumferential speed of the roll increases, the reverse flow speed also increases and the water is ejected backward (splash).

Furthermore, when the circumferential speed of the rolls (2) (4') decreases, the length of the first half of the entrance side nip section becomes 1 for the same liquid supply amount.
．． ) increases, the pressure gradient at the inlet decreases, and air becomes more likely to be trapped, resulting in skipping.

The present invention was proposed in order to solve the above-mentioned conventional drawbacks, and the upper plate forming the tip of the liquid supply nozzle is arranged so as to be almost perpendicular to the line connecting the centers of the upper and lower two rolls,
In addition, by providing an overflow roller near and below the exit of the liquid supply nozzle, it is possible to provide a transfer device for a coater that does not cause the splash or skip that occurs in the prior art.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows an embodiment of the present invention, in which (1) is a base paper, (C) is a packing roll, (t) is an applicator roll, and (S) is a blade. , (6) are the saucers, which are the same as the conventional device shown in Fig. 7. What differs from the conventional device is the liquid supply nozzle (7).
).

The liquid supply nozzle (7) has an upper plate (7a) forming its tip.
is almost horizontal (almost perpendicular to the line connecting the centers of the two rolls (,2) (4')), and there is an o/
<7 tff-mouth (g). overflow D
(, ri & edge elastic plate (9) is provided, and the tip of the elastic plate (l) forming the bottom plate of the tip is in contact with the applicator roll (tI). The upper surface of the upper plate (7a) has a minimum distance from the base paper (1) on the packing roll (2).

Next, to explain the operation of the embodiment shown in FIG.
) flows downward without contacting any rolls.

The opening degree of the overflow roller (A') is naturally adjusted by the elastic plate (9) according to the overflow lever.The elastic plate (lθ) also moves the applicator roll (+) up and down to adjust the gap. It also serves as a liquid seal.It also serves as a liquid seal between the upper plate (io) of the upper surface of the liquid supply nozzle (7) and the base paper (1
), and the lower elastic plate (10) is brought into contact with the applicator roll (4') to almost completely close the nip entrance.

Fig. S shows an embodiment of the present invention which is similar to Fig. 2, in which the elastic plate (10) of Fig. 1 is omitted, so that the overflow flows down while contacting the applicator roll. This is what I did. However, although the overflow and the movement direction of the applicator roll (ri) are opposite, the circumferential speed of the applicator roll (da) is low, and the center of the roll (ko) (da) is Since the upper side plate (7a) is provided so as to be almost perpendicular to the connecting line, the overflow is prevented from coming into contact with the high-speed base paper (1), and the flow is stable and no splash occurs. .

Since the present invention is configured as explained in detail above,
The main flow A→B (Fig. 9) smoothly enters the nip between the two rolls without bending, making the overall flow stable and preventing skips and splashes. Also, backflow part E
Since the backflow direction E→F is directed into the liquid supply nozzle, there will be no splashing to the outside even if the backflow speed increases.

In addition, since the upper plate that forms the tip of the liquid supply nozzle is arranged to be almost perpendicular to the line connecting the centers of the upper and lower λ rolls, the nip entrance of the λ rolls is almost completely covered by the liquid supply nozzle. As a result, the length lI of the inlet side nip portion does not exceed 1 m, ensuring the inlet pressure gradient is at least a certain value, reducing the amount of air trapped in the nip portion, and preventing skipping. In addition, by forming a lower surface at the tip of the liquid supply nozzle and providing an elastic plate in contact with the applicator roll, the overflow will flow out without coming into contact with the applicator roll, resulting in a stable overflow and further preventing splashes. It's completely possible.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an example of a conventional paper coater, and FIG. 2 is a side sectional view of a transfer device of a coater showing an embodiment of the present invention.
Figure 3 is an explanatory diagram showing the flow state of the coating fluid in the case of Figure 7, Figure q is an explanatory diagram showing the flow state of the coating fluid in the case of Figure 2, and Figure S is an explanatory diagram showing the flow state of the coating fluid in the case of Figure 2. FIG. 3 is a side sectional view of a transfer device of a coater showing an embodiment different from the one shown in the figure. Explanation of the main parts of the diagram/... [utE) 2...Packing roll q...Applying roll? ...Liquid supply/
Zuru 7a...Upper plate g...Overflow 9...Elastic plate Patent applicant Mitsubishi Heavy Industries, Ltd.

Claims (1)

[Claims] In a device that supplies liquid from a liquid supply nozzle between an upper roll on which a sheet is hung and a lower applicator roll, the upper plate forming the tip of the liquid supply nozzle is connected to a line G+1 connecting the centers of the two rolls. A transfer device for a coater, which is arranged at a nearly right angle and has an overflow roller located below the mouth of the liquid supply nozzle.