JP2000119985A - Shoe press device for paper machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To change the profile of a nip without exchanging a pressurizing shoe and optimize water squeezing effects by rotating a main shaft of a nip regulating mechanism to a minute angle with an actuator. SOLUTION: This shoe press device 11 is composed by rotating a main shaft 8 of a nip regulating mechanism with an actuator 9 and making the interval between a curved surface 70 of a pressurizing shoe 4 and an outer peripheral surface 73 of a pressing down roll 72 equal over the whole surface, etc., then actuating the shoe press device 11, pressurizing and nipping a paper sheet 57 through a presleeve 63 and felt belts 55 and 56, subsequently providing a guided surface 7 sliding on a guiding surface 3 extendedly provided in the front and rear directions of the nip, rotating the main shaft 8 freely rotatably screwed into a screw hole 5 bored in the sliding direction of an engaging protrusion 6 sliding in a groove 2 formed in a pressurizing piston 1 to a minute angle with the actuator 9 and changing the profile so that the nipping plane pressure can finely be adjusted without exchanging the pressurizing shoe 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shoe press device of a paper machine used for dewatering in a paper manufacturing process, and in particular, improves a dewatering performance by changing a profile of a gap between a pressing roll and a pressing shoe. In addition, it is possible to eliminate the troublesome adjustment work of replacing the pressure shoe.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a conventional paper machine 50.
The paper machine 50 is broadly divided into a pulp solution supplied from the header 52, and the pulp solution is spread in the width direction.
A head box 51 for spraying between the wire belts 3 and 54; a wire part A for dehydrating and forming a paper layer while moving on the wire belt 54; and a paper sheet 57 containing water conveyed by the wire belt 54 for felt belt 55. , 56, which presses the water of the paper sheet 57 by the shoe press device 60 in the process of transport and densifies the tissue.
And a dryer part C which is dried and finished by the dryer cylinder 58 in the process of receiving and conveying the paper sheet 57 still wet after the water squeezing on the canvas belt 59.

[0003] Of the three parts, the press part B determines the paper quality of the paper sheet 57 and determines the consumption of the drying steam in the dryer part C. Therefore, the press part B is important not only in terms of cost but also in terms of resource saving. Process.

FIG. 4 is a cross-sectional view of the shoe press device 60 shown in FIG. 3 cut along a plane perpendicular to the center axis of the roll 72. In FIG. 4, a cylindrical supporting beam 65 is provided in parallel above the pressing roll 72, and a pressing cylinder 67 is provided on a lower outer peripheral surface of the supporting beam 65 in parallel with the center axis of the pressing roll 72. Provided.

The pressurizing cylinder 67 has a pressurizing piston 68
Are slidably provided above and below, and a pressure shoe 69 is fixed below the pressure piston 68.

The surface (lower surface) of the pressure shoe 69 facing the outer peripheral surface 73 of the pressing roll 72 is a cylindrical curved surface 70 corresponding to the outer peripheral surface 73, and the curved surface 70 is in contact with the outer peripheral surface 73. The nip is formed by being arranged so as to maintain a required interval.

Pressure oil is introduced into a hydraulic chamber 66 formed between the pressurizing cylinder 67 and the pressurizing piston 68 via a control valve (not shown) from a hydraulic source (not shown). The pressure shoe 69 is pressed toward the central axis of the roll 72.

[0008] Pressing shoe 69 and supporting beam 6
5 is enclosed in the pre-sleeve 63, and the space between the pre-sleeve 63 and the supporting beam 65 is filled with a lubricating oil 64.

The nip between the outer peripheral surface 73 of the pressing roll 72 and the pre-sleeve 63 on the curved surface 70 of the pressing shoe 69 is supplied with a paper sheet 57 sandwiched between felt belts 55 and 56. While being compressed by the pressing force of the pressing shoe 69, it is fed in the direction of arrow D together with the felt belts 55 and 56 with the rotation of the pressing roll 72. The pre-sleeve 63 is made of lubricating oil 6
4, the sliding resistance of the felt belt 55 is reduced by sliding on the curved surface 70 of the pressing shoe 69.

[0010]

In this case, the pressing roll 7 is used.
The optimum condition of the surface pressure (hereinafter referred to as the nip surface pressure) generated on the paper sheet 57 by the nip between the outer peripheral surface 73 of the second and the curved surface 70 of the pressure shoe 69 depends on the papermaking conditions (papermaking speed, material concentration,
Roll roll diameter, shape of the pressure shoe opposing surface of the pressure shoe)
It changes with.

For this reason, conventionally, a pressing cylinder 69 is used to press a pressing shoe 69 having a curved surface 70 formed so as to accurately match the outer peripheral surface 73 of a pressing roll 72 to reduce the required nip surface pressure. I was trying to get it.

FIG. 2 shows the nip surface pressure generated on the paper sheet 57 via the felt belts 55 and 56 on the pressure shoe 69 of the shoe press device 60 (hereinafter, the load application range of the pressure shoe 69 is referred to as nip width). Show. In FIG. 2, the nip surface pressure c indicates the nip surface pressure when the outer peripheral surface 73 of the pressing roll 72 and the curved surface 70 of the pressing shoe 69 shown in FIG. “d” indicates the surface pressure generated on the paper sheet 57 when the paper sheet 57 is pressed between two reduction rolls provided with the central axis provided in parallel.

In FIG. 2, it is known that the maximum surface pressure of the nip surface pressure c is significantly lower than the surface pressure d, but the amount of water removed is superior. It is known that by increasing the pressure and rapidly reducing the pressure in the zone 3, the water can be more effectively squeezed without damaging the paper quality. Further, as in the case of the nip surface pressure b, the pressure can be rapidly increased in the zone 1 and the pressure can be gently reduced in the zones 2 and 3, or the characteristics of the nip surface pressures a and b can be further variously changed. Therefore, from the viewpoint of energy saving of the dryer part C, it is necessary to consider the nip surface pressures a, b, and c and the nip shape showing the characteristics obtained by changing them.

Since the nip shape requires an accuracy of 1/100 mm unit, conventionally, various types of pressure shoes 69 formed with high accuracy according to the papermaking conditions are prepared, which is very uneconomical. Also, when mounting the pressure shoe 69, the positioning is also required to have the same accuracy, so that the adjustment is very difficult.

[0015]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the first means is to provide a pressing roll 72 provided in a press part of a paper machine and an outer periphery of the pressing roll 72. A pressing shoe 4 having a curved surface 70 forming a nip facing the surface 73 and being arranged at a predetermined interval with respect to the pressing roll 72; A press cylinder 67 for pressurizing toward the central axis of the paper machine, wherein the press shoe 4 is provided with an adjusting mechanism for moving the press shoe 4 by a small distance in the front-rear direction of the nip. I have.

According to the first means of the present invention, when the pressing shoe 69 is slightly moved in the rotation direction of the pressing roll 72 (behind the nip), the outer peripheral surface 73 of the pressing roll 72 and the curved surface 70 of the pressing shoe 69 are moved. Is gradually narrower and wider at first as the roll 72 rotates. At this time, the paper sheet exhibits a nip surface pressure corresponding to FIG. When the pressure shoe 69 is slightly moved in the reverse direction (forward of the nip), the paper sheet exhibits a nip surface pressure corresponding to FIG.
Therefore, by moving the pressure shoe 69 in the front-rear direction of the nip, the nip surface pressure in FIG. 2 can be arbitrarily adjusted so as to have a, b, c, and variously changed characteristics. .

Further, according to the first means of the present invention, there is an effect that the nip shape determined by many papermaking conditions can be examined in advance by a simple method. Further press shoe 69
By adjusting the moving direction and the moving amount of the nip, it is possible to obtain more appropriate examination data of the nip shape. For this reason, there is no need to manufacture a special nip-shaped pressure shoe in advance, and there is also an effect that the troublesome work of mounting these prototype pressure shoes with high accuracy can be omitted.

In the second means of the present invention, the pressure shoe 4
The adjusting mechanism is a guide surface 3 extending in the front-rear direction of the nip.
And a pressurized piston 1 having a guide groove 2, a guided surface 7 that slides on the guide surface 3 of the pressurized piston 1, and an engagement projection 6 that slides on the guide groove 2. A pressure shoe 4 having a screw hole 5 drilled in the sliding direction of the engagement protrusion 6, a main shaft 8 rotatably screwed into the screw hole 5 of the pressure shoe 4, and rotating the main shaft 8. It comprises an actuator 9.

According to the second means of the present invention, it is possible to finely adjust the moving amount of the pressing shoe 4 with respect to the pressing roll 72, and to ensure reproducibility of the position. Therefore, the nip shape can be accurately reproduced.

Further, since it is easy to obtain a structure having sufficiently high rigidity, there is little possibility of deformation due to an eccentric load.

[0021]

FIG. 1 shows an example of an embodiment of a shoe press apparatus 11 according to the present invention.
2 is a cross-sectional view taken along a plane perpendicular to the central axis of FIG.
Only the pressurizing piston 1 and the pressurizing shoe 4 partially show the external shape. In FIG. 1, the same parts as those of the conventional example are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, on the lower surface of the pressure piston 1,
A guide surface 3 and a guide groove 2 extending in the front-rear direction (horizontal direction in FIG. 1) of the nip are formed. Pressure shoe 4
Is provided on its upper surface with a guided surface 7 guided by the guide surface 3 on the lower surface of the pressurizing piston 1 and a engagement projection 6 engaging with the guide groove 2 of the pressure piston 1. It is slidably supported in the direction of the guide groove 2 on the lower surface. The outer surface (lower surface) of the pressing shoe 4 facing the outer peripheral surface 73 of the pressing roll 72 has a curved surface 70 so as to generate an appropriate nip surface pressure.
Has been processed.

A screw hole 5 is formed in the pressure shoe 4 along the sliding direction of the engagement protrusion 6 and the guided surface 7.
A main shaft 8 is rotatably screwed into the screw hole 5.

An actuator 9 is fixed to the pressure piston 1, and an output shaft of the actuator 9 is connected to one end of the main shaft 8. Power is supplied to the actuator 9 from a power source (not shown). A rotation sensor is provided on the opposite side of the joint between the actuator 9 and the main shaft 8.
A control circuit 10 is attached.

Next, the operation of the above embodiment will be described.

In FIG. 1, when the main shaft 8 is a right-hand thread, the main shaft 8 is rotated left and right by the actuator 9 so that the distance between the curved surface 70 of the pressure shoe 4 and the outer peripheral surface 73 of the pressing roll 72 becomes equal over the entire surface. When the shoe press device 11 is operated by moving the shoe press device 11 to a position (hereinafter, this position is referred to as a center), a nip surface pressure c shown in FIG. 2 appears on the paper sheet 57 via the pre-sleeve 63 and the felt belts 55 and 56.

Next, when the main shaft 8 is rotated clockwise by the actuator 9 to move the pressure shoe 4 to the actuator side (to the rear of the nip), the nip surface pressure of the paper sheet 57 corresponds to that of FIG. Becomes If the main shaft 8 is further advanced to the right by a small angle at this position, the nip surface pressure becomes as shown in FIG.
The rising of the zone 1 becomes even steeper with respect to b, and the maximum surface pressure rises. The maximum surface pressure in zone 3 decreases, the surface pressure drop becomes gentle, and the gradient in zone 2 becomes slightly steep.

When the main shaft 8 is returned to the left by a small angle, the gradient of the zone 1 becomes gentle with respect to b in FIG. 2 and gradually approaches the nip surface pressure c.

The main shaft 8 is rotated counterclockwise by the actuator 9 to move the pressure shoe 4 beyond the center and move the actuator 9
If you move in the direction away from the front (in front of the nip)
The nip surface pressure corresponds to FIG. In addition, the inclination of the nip surface pressure a can be finely adjusted by rotating the main shaft 8 left or right in the same manner as in the previous section.

As described above, according to the embodiment of the present invention, the pressing shoe 4 having the curved surface 70 at the position opposing the outer peripheral surface 73 of the pressing roll 72 is moved forward and backward of the nip to thereby provide the nip. By changing the shape, the water squeezing effect can be measured, and the shape of the desired nip surface pressure can be examined in advance. Furthermore, there is an effect that it is free from the trouble of mounting and adjusting the individually processed pressure shoes with high precision.

The shoe press device 11 of the present invention is not limited to the above-described embodiment, but any known displacement drive device can be employed. The shape of can be selected variously,
Of course, various changes can be made without departing from the scope of the present invention.

In this embodiment, for example, by pressing the front and rear sides of the pressure shoe 4 with different pressures with different pressure cylinders, the nip surface as shown in FIG. Although it is conceivable to obtain a pressure, it is difficult for a shoe press device requiring control of 1/100 mm to secure the accuracy, and thus it is difficult to adopt this method.

[0033]

According to the first aspect of the present invention, the reduction roll 7 is provided.
By moving the pressure shoe 4 having the curved surface 70 at a position opposing the outer peripheral surface 73 of the second nip before and after the nip, the nip shape can be changed and the water squeezing effect can be measured. The shape of the pressure can be considered in advance. Furthermore, there is an effect that it is free from the trouble of mounting and adjusting the individually processed pressure shoes with high precision.

According to the invention of claim 2, the reduction roll 72
In contrast, the amount of movement of the pressure shoe 4 can be finely adjusted, and reproducibility of the position is ensured. This has the effect that the nip shape can be accurately reproduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view taken along a plane perpendicular to the center axis of a pressing roll of a shoe press device according to the present invention, showing only a partial appearance of a pressing piston and a pressing shoe.

FIG. 2 is a diagram showing nip surface pressures when a shoe press according to the present invention, a conventional shoe press, and two pressing rolls are used.

FIG. 3 is an overall view showing an example of a paper machine.

FIG. 4 is a cross-sectional view illustrating an example of a conventional shoe press device when cut along a plane perpendicular to the center axis of a pressing roll.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 pressure piston 2 guide groove 3 guide surface 4 pressure shoe 5 screw hole 6 engagement protrusion 7 guided surface 8 main shaft 9 actuator 67 pressure cylinder 70 curved surface 72 reduction roll 73 outer peripheral surface of roll

Claims (2)

[Claims] 1. A pressing roll (72) provided in a press part of a paper machine, and an outer peripheral surface (7) of the pressing roll (72).
A pressing shoe (4) having a curved surface (70) facing the 3) and forming a nip and being arranged at a predetermined interval with respect to the pressing roll (72); A pressurizing cylinder (67) for pressurizing the pressurizing roll (72) toward a central axis of the pressing roll (72) by a pressurizing piston (1). A shoe press device for a paper machine, comprising: an adjusting mechanism adapted to move a minute distance in a direction. 2. An adjusting mechanism comprising: a pressurizing piston (1) having a guide surface (3) and a guide groove (2) extending in the front-rear direction of a nip; and a guide surface of the pressurized piston (1). It has a guided surface (7) that slides on (3) and an engagement protrusion (6) that slides on the guide groove (2), and is provided in the sliding direction of the guided surface (7) and the engagement protrusion (6). A pressure shoe (4) having a perforated screw hole (5), and a screw hole (5) of the pressure shoe (4).
2. A shoe press device for a paper machine according to claim 1, further comprising a main shaft rotatably screwed to said main shaft, and an actuator for rotating said main shaft.