JPH0513424Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a pressurizing device for a roll coater, which is normally provided between a group of dryers in a paper machine and applies paint liquid, etc. to paper dried in a pre-dryer section.

<Conventional technology and its problems> A roll coater is usually installed between the pre-dryer section and the after-dryer section of the dryer group of a paper machine, and is used to apply paint liquid, sizing liquid, etc. to paper that has been dried in the pre-dryer. The wet paper coated with the liquid is then dried in an afterdryer.

A typical roll coater will be explained with reference to the drawings.

FIG. 2 is a front view of the roll coater. The roll coater applies a coating liquid to the paper 11 by passing the paper 11 through a nip 12 formed by pressing a pair of rubber-wrapped applicator rolls, that is, a top applicator roll 3 and a bottom applicator roll 2 against each other. It is something. A pair of gate rolls, ie, inner gate rolls 6, 6 and outer gate rolls 7, 7, are pressed on both sides of the pair of applicator rolls 2 and 3, respectively. The coating liquid is supplied to the nip portion 13 of the pair of gate rolls. The applicator rolls 2 and 3 are driven so that their surface speeds are the same as the running speed of the paper, and the gate rolls 6 and 7 are driven so that their surface speeds are slower than the surface speed of the applicator rolls. The coating liquid supplied to the nip portion 13 of the gate roll passes through the surfaces of the inner gate rolls 6 and 6 and the surfaces of the applicator rolls 2 and 3, respectively, and is applied to the surface of the paper. The bottom applicator roll 2 has bearings 2a, 2a fixed to a pair of frames 1, 1 provided on the front side (operation side) and the back side (drive side) of the roll, respectively. The top applicator roll 3 is mounted on a pair of arms 4, 4 which are swingably supported from the frame 1, and bearings 3a, 3a at both ends.
is supported. The arm 4 is connected to an air spring 5 supported by the frame 1, and when compressed air is supplied to the air spring 5, the air spring stretches and presses the top applicator roll 3 against the bottom applicator roll 2. When the air in the air spring 5 is released, the top applicator roll 3 separates from the bottom applicator roll 2 due to its own weight, and the nip is opened. The inner gate rolls 6 and 6 have bearings at both ends supported by an arm 4 and an arm 8 that is swingably supported from the frame 1, and the outer gate roll is an arm that is swingably supported from the arm 8. 9 supports bearings at both ends, and air springs 10 support the inner gate rolls 6, 6 to the applicator rolls 2, 3, and the outer gate rolls 7, 7 to the inner gate rolls 6, 7.
6, respectively, to be pressurized and released.

Although this example describes a case in which gate rolls are provided on both applicator rolls, there are various roll coaters, such as those with only one of the top or bottom applicator rolls, and those without gate rolls. .

<Problems to be solved by the invention> Paper passing through such a roll coater is performed in the following steps.

First, the nips of the applicator rolls 2 and 3 are opened, and the edges of the paper are passed through. Next, expand the edges and thread the entire width of the paper. Thereafter, the applicator rolls are pressed together and normal operation is achieved. Meanwhile, top applicator roll 3
The stroke from the open state of the nip to the state where they are pressed against each other follows the change in diameter due to wear of the rolls, so it is quite large and is equivalent to 50 to 100 mm when converted to the stroke of the air spring 5. After passing the paper, when the top applicator roll 3 is moved forward from the retraction limit toward the bottom applicator roll 2, the stroke is large, so it is difficult to move the front and back sides of the roll in perfect synchronization. When the applicator rolls start coming into contact with each other, a phenomenon of uneven contact from one end of the rolls may occur, and paper breaks often occur from the uneven contact area, causing a large amount of paper waste.

<Purpose of the invention> The present invention was devised in view of the above problems, and is a roll coater that prevents the applicator roll from hitting unevenly when paper is passed through, thereby eliminating one of the causes of paper waste. The purpose is to provide a pressurizing device for

<Means for Solving the Problems> In order to achieve the above object, the pressurizing device of the roll coater of the present invention applies paint to the surface of the paper by passing the paper through a nip formed between a pair of applicator rolls. A pair of arms that swingably support bearings at both ends of one applicator roll of a roll coater that applies liquid, etc., and an actuator such as an air spring that is connected to the arms and pressurizes and releases the roll. In a pressurizing device for a roll coater, when the roll is moved from the open side of the nip to the pressurizing side, before the rolls come into contact with each other, each of the above-mentioned pair of arms contacts the above-mentioned pair of arms, and a slight parallel gap between the pair of applicator rolls is applied. A stopper is provided that allows the two applicator rolls to contact simultaneously over the entire width by leaving a gap and releasing the contact on both sides at the same time. a screw rod provided at the tip of the arm; a cross shaft provided in front of the screw rod; an arm provided at both ends of the cross shaft; and an applicator provided on the arm facing the tip of the screw rod. It is characterized by having a cam follower that comes into contact with the tip of the screw rod when the roll approaches, and a rotation drive means that rotates the cross shaft to release the contact.

<Function> When the top applicator roll 3 is moved from the open side of the nip to the pressure side, the stopper that contacts the arm temporarily stops the movement of the roll just before the roll contacts the nip, and then the stopper comes into contact with the stopper. Both ends are released at the same time by rotating the cross shaft, so the subsequent movement of the rolls is minimal, and the movements of the front and back sides of the rolls are perfectly synchronized, and the rolls are in contact over their entire width at the same time. . Therefore, there is no occurrence of uneven contact from one end of the roll when the applicator roll starts contacting, and there is no paper breakage caused by uneven contact.

<Example> An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view of the stopper of the pressurizing device of the present invention.

The pressurizing device for a roll coater according to the present invention is a conventional pressurizing device with a stopper attached, and other parts are the same as the conventional pressurizing device, so a description thereof will be omitted.

In FIG. 1, 20 is a cross shaft, 21
22 is an air cylinder, 23 is a bracket attached to the lower end of the arm 4, and 24 is a screw rod attached through the bracket 23. The cross shaft 20 is attached between the pair of frames 1, 1, passing through each frame 1, and is rotatably supported by a bearing (not shown) attached to the frame 1. The arms 21 are fixed to both ends of the cross shaft,
The tip of the arm 21 is connected to a piston rod of an air cylinder 22. As shown in the figure, the arm 21 is provided with a protrusion 21a at a position approximately 70° out of phase with respect to the arm center line 21b (the line connecting the arm rotation center and the piston rod connection point).
A cam follower 21C is attached to the tip of the protrusion. Screw rod 24 is bracket 23
By rotating the screw rod rod 24, the position of the tip of the rod can be adjusted.

Next, the action will be explained.

Paper is passed through the applicator rolls 2 and 3 of the roll coater in an open state, and after passing the paper, the top applicator roll 3 is advanced toward the bottom applicator roll 2 from the backward limit. At this time, the air cylinder 22 is in a retracted state, and the protrusion 21
a is positioned opposite to the tip of the screw rod 24. When the top applicator roll 3 moves forward as described above, the tip of the screw rod 24 comes into contact with the protrusion 21a just before the end of the stroke, and the roll stops moving forward. The position of the screw rod 24 relative to the bracket 23 is adjusted so that a small gap (for example 1-2 mm) remains between both applicator rolls 2, 3 when the rolls come to rest. Next, when the piston rods of the pair of air cylinders 22 are projected, the arm 21 rotates,
The contact between the protrusion 21a and the tip of the screw rod 24 is released. At this time, since the pair of arms 21 are connected by the cross shaft 20, they rotate in synchrony, and contact with the screw rod 24 is released on both sides at the same time. Also, the contact between the protrusion 21a and the tip of the screw rod 24 is caused by the cam follower 21c.
Therefore, the frictional force that acts when the contact is released is very small, and the movement is performed smoothly.

When the contact is released, the top applicator roll 3 moves further forward, and the bottom applicator roll 2
come into contact with. Since the stroke at this time is extremely small, synchronization is perfect and no uneven contact occurs at the start of contact.

Note that various modifications are possible, such as using an air cylinder instead of an air spring as the actuator for pressurizing the roll.

<Effects of the invention> As described above, the invention has the following effects.

(1) The applicator rolls contact each other simultaneously over the entire width after passing the paper, and there is no uneven contact, reducing the chance of paper breakage and the occurrence of paper waste.
It has effects such as improving productivity and saving energy.

(2) Although the structure of the stopper is simple and inexpensive, it operates reliably.

[Brief explanation of the drawing]

FIG. 1 is a front view of a stopper of a pressurizing device for a roll coater according to the present invention, and FIG. 2 is a front view of the roll coater. 1...Frame, 2...Bottom applicator roll, 3...Top applicator roll, 4...
arm supporting the top applicator roll; 5;
...Air spring, 12...Nip, 20...Cross shaft, 21...Arm, 22...Air cylinder.

Claims (1)

[Scope of utility model registration request] A pair of arms that swingably support bearings at both ends of one applicator roll of a roll coater that passes paper through a nip formed between a pair of applicator rolls and applies paint liquid, etc. to the surface of the paper. and an actuator such as an air spring connected to the arm to pressurize and release the roll, in which the roll comes into contact when moving the roll from the open side of the nip to the pressurized side. Before doing so, the two applicator rolls are completely moved by contacting the pair of arms and stopping them with a slight gap left in parallel between the pair of applicator rolls, and releasing the contact on both sides at the same time. A stopper is provided that simultaneously contacts the width of the applicator roll, and the stopper includes a screw rod provided at the tip of the arm of the applicator roll, a cross shaft provided in front of the screw rod, and a stopper that contacts the screw rod provided at the end of the arm of the applicator roll, the cross shaft provided in front of the screw rod, and the cross shaft. An arm provided at both ends, a cam follower provided on the arm facing the tip of the screw rod, which comes into contact with the tip of the screw rod when the applicator roll approaches, and a cross shaft that rotates to release the contact. A pressurizing device for a roll coater, characterized in that it has a rotational drive means for rotating.