JPS59157396A - Crown variable roll - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable crown roll that can be applied to paper machines, paper finishing machines, etc.

In paper machine presses, calenders, paper finishing machines, etc., a nip is formed between multiple rolls, an appropriate load is applied, and a uniform nip pressure is applied in the longitudinal direction of the roll surface to achieve the desired result. moisture, paper thickness, smoothness, etc.

When a load is applied to the nip, the roll flexes, so in order to obtain uniform nip pressure, a well-known and inexpensive method is to use a medium-height roll with a pre-crowned roll. .

However, if the nip pressure load is always constant, the above-mentioned medium-high rolls will be sufficient, but if the nip pressure load has to be changed frequently, the medium-high rolls with fixed crowns will no longer be satisfactory, and the nip It is desirable to use a variable crown roll that can adjust the crown to correspond to the pressure load.

For this variable crown roll, a large number of rolls having a structure as disclosed in Japanese Utility Model Publication No. 43-23043 are manufactured and used as adjustable mid-height rolls.
It greatly contributes to the ease and rationalization of operations such as presses and calender sections.

However, the above-mentioned adjustable medium height roll forms a nip, and theoretically it is possible to obtain a uniform nip pressure along the entire length of the roll with the mating roll for any nip pressure load.

However, in reality, the basis weight (weight per unit area) and moisture content of the wet paper transferred from the stock inlet and wire section may not be uniform in the width direction, and in the press, felt etc. In calenders, slight deformation of the rolls due to temperature variations in the rolls and paper often coexists, so in this case it becomes necessary to locally adjust the nip pressure.

However, in the conventional adjustable medium-height roll, the fluid pressure for crown A adjustment is common and the same value over the entire length of the roll, so it is impossible to locally adjust the nip pressure in any part. It's possible.

The present invention was proposed in order to eliminate the above-mentioned conventional drawbacks, and in the variable crown roll used in the location where the nip is formed, the present invention has been proposed to improve the roll surface length direction, which could not be achieved with the conventional variable crown roll. Nip pressure at any part,
The aim is to provide a roll with locally adjustable functionality.

To achieve this objective, the present invention provides a fluid pressure chamber that is controlled to maintain a continuous nip pressure within the roll cell and a shoe device that creates a support fluid film from the lubricating fluid within the roll cell, which is non-rotatably fixed. In addition to the conventional variable crown roll, which is provided on the center shaft along almost the entire length of the roll, there are also multiple fine-adjustment fluid pressure chambers and shoe devices with a similar structure that are subdivided and grouped on the opposite side of the fluid pressure chamber and shoe device. The purpose is to provide a variable crown roll that also has the function of locally adjusting the nip pressure in the longitudinal direction by assembling the rollers.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a variable crown roll in an embodiment of the present invention, and FIG. 2 is a sectional view taken along line XX in FIG. 1. Moat number 3
The figure is a schematic representation to make it easier to understand how a load is applied, and FIG. 4 shows another embodiment.

First, in Fig. 1, a rotatable bearing link (3) is attached around a center shaft (2) which is fixed so as not to rotate by a torque arm (1) or some other method.
), in which a fluid pressure chamber (6) for crown adjustment and a shoe are installed in the direction toward the mating roll (5) forming a nip. Device (forced).

The fluid pressure chamber (6) has a conduit (8) that can supply fluid pressure.
) is introduced, and the crown can be changed by adjusting this fluid pressure. Since the above structure is publicly known from Japanese Utility Model Publication No. 4.3-23048, detailed explanation will be omitted here.

Now, in the embodiment shown in FIG. 1, a fluid pressure chamber (6), a shoe device (force), and a plurality of sets that are subdivided and grouped discontinuously along the entire length of the roll in the direction directly opposite to the mating roll (5) are used. A fluid pressure chamber (9a) (g5) (9C) and a shoe device (■0cL) (10h)σOC) for fine adjustment are provided, and each fluid pressure chamber is connected to a conduit (11α) that can supply fluid pressure.
)(11/))(11C). In this figure, three sets of fine adjustment fluid pressure chambers and shoe devices are shown, but the number of sets is not limited and may be set in smaller numbers.

Also, the fluid pressure chamber (6) and the fine adjustment fluid pressure chamber (9a)
(9A) and (9C) are connected to fluid supply devices that can set different fluid pressures.

Fig. 4 shows an embodiment different from Fig. 1; in the example of Fig. 1, the shoe device is a fine adjustment fluid pressure chamber (9G) (91)).
Paired with (90) (loa) (IOA) (
10C), whereas in the example shown in Figure 4, there are fine adjustment fluid pressure chambers (9a) (95) (9
The shoe device 00), which engages C), is continuous and integral. The example shown in FIG. 4 has the same structure as that shown in FIG. 1 except for this shoe device, and detailed explanation will be omitted.

The variable crown roll with the structure shown in Figures 1 and 4 is
Since the roll cannot be driven by itself, it is rotated by the driving force from the other roll. However, it is also possible to use a drive type roll that can be driven by itself by attaching a prime mover to the end of the roll. It is not limited.

Next, to explain the operation, FIG. 3 schematically shows the variable crown roll having the structure shown in FIGS. 1, 2, and 4. In FIG. 3, a nip is formed by a plurality of rolls, and when loads Fl and F2 are applied to the rolls, the rolls deflect, but this deflection is corrected by fluid pressure (20).

In this case, if the nip pressure is high at the center of the roll on the plate and low at the end of the roll, lower the fluid pressure (20) set value, and if the opposite is the case, increase the fluid pressure (20) set value. This results in uniform nip pressure over the entire length of the roll.
No special problems occur during normal normal operation. However, it is not possible to locally adjust the nip pressure by adjusting only the fluid pressure (20).

Adjust the fine adjustment fluid pressure (2) in the opposite direction to the fluid pressure (20) position.
1) (22) (23), this area A, C
, D, a fluid pressure difference in both directions acts on the cell (4).

On the other hand, in region B which does not have a fluid pressure chamber for fine adjustment, only the fluid pressure (20) at the position facing the mating roll (5) acts on the cell (A), so local nip pressure adjustment is possible. It becomes possible. Furthermore, fluid pressure (21) (22) (c)
The areas (A) CB) (C) [F]) in Fig. 3 are set to different pressures, respectively, and the opponent roll (
5) It becomes possible to obtain different nip pressures.

In the example of FIG. 1 with the L roller, the fine adjustment fluid pressure 'M' and the shoe device (9a) σOa), (9') (
10b), (9') (10C) are provided, but
It will be easily understood that by increasing the number of sets, the number of local nip pressure adjustment areas can be increased.

It should be noted that it is also possible to set the fine adjustment fluid pressure (21) (22) f231 to zero, and it will be easily understood that if it is set to zero, it can be used as a round variable opening in the same way as in the conventional case.

Since the present invention is configured as explained in detail above,
In variable crown rolls that form a nip with a plurality of rolls, it is possible to locally adjust the nip pressure in the longitudinal direction of the roll surface. Furthermore, since the fluid pressure chambers are provided at the top and bottom of the roll, a vibration-proofing effect can be obtained.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of a variable crown roll showing one embodiment of the present invention, Fig. 2 is a sectional view taken along line XX in Fig. 1, and Fig. 3 is a schematic diagram clearly showing how a load is applied. , FIG. 4 is a side sectional view of a variable crown roll showing an embodiment of the present invention different from FIG. 1. Explanation of the main parts of the diagram 2...Center shaft 301. Bear link 4 (... cell 5... mating roll 6... fluid pressure chamber 7... shoe device 8... conduit 94, 9A, 9c... fine adjustment fluid pressure chamber loa
, 10b, 10c...Segmented shoe device patent Applicant: Mitsubishi Heavy Industries, Ltd.

Claims (1)

[Claims] In variable crown rolls consisting of cells rotatably supported by bearings around a fixed center shaft, a continuous roll with a length approximately equal to the full length of the roll in the direction toward the mating roll forming the nip. A fluid pressure chamber for crown adjustment and a shoe device having a straight or nearly continuous shape are provided, and a plurality of fluid pressure chambers for fine adjustment are discontinuously subdivided and grouped in the opposite direction. A variable crown roll characterized in that it is provided with a discontinuously segmented shoe device or a continuous integral shoe device that engages a pressure chamber.