JP3021223B2 - Twin wire paper machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double wire system, in which all wire parts and a top wire capable of providing a section where two wires can run across a raw material at a portion other than on a roll are provided (expansion). The present invention relates to a twin-wire paper machine which can be applied to a single-wire type wire part or the like in which two wires can run in parallel.

[0002]

2. Description of the Related Art Referring to FIGS. 6 and 7, an example of a conventional double wire type wire part will be described.
There are a curved shoe 1, a dehydrating blade (or deflector) 2, a curved or flat suction box 3, and the like. The curved shoe 1 dewaters the raw material (jet) from the head box 4 by sandwiching the raw material (jet) between the wires 5 and 6 with the pressure generated by the tension of the wire 5 along the curvature of the shoe 1 and dispersing the fiber. Ability is small. Dehydration blade 2
Is the raw material (jet) ejected from the head box 4
The material is dewatered by pressing the required number of blades 2 into the wire loop and the pressure generated by the wire tension while sandwiching the raw material between the wires 7 and 8. Is removed by the scraping action of the blade 2.

[0003]

As described above, in the conventional means, the dispersion is promoted due to the side effect during dehydration. As the dehydration proceeds, the raw material concentration increases, and the dispersion effect is significantly reduced. Cannot accumulate. In particular, the raw material subjected to the dehydration action by these devices is concentrated from the vicinity of the wire on the device side, and the fiber mat grows. Therefore, if an excessive action is given, the fiber mat may even be broken. Therefore, the arrangement of the dehydrating devices is arranged in consideration of the balance between the dehydrating power and the dispersing effect at the time of dehydrating. As a result, it is considered that when the concentration is about 2% or more, it is difficult to disperse the raw material in the wire part. An expensive device was desired. By the way, the dispersion of the fibers basically proceeds by the relative motion between the fibers and the white water in which the fibers are suspended. The present invention solves the problems such as the difficulty of dispersing the conventional raw material in the wire part, and the first is to make full use of the movement of the white water, and the second is to restrict the function of the device to only the dispersion. An object of the present invention is to provide a twin-wire paper machine that can handle high-concentration raw materials.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a paper machine having two wires running across a raw material, and a supporting device for supporting one of the wires in a concave shape in a raw material jet supply section. A water injection hole for forming a water film is provided on the concave support surface on the upstream side of the raw material jet landing part of the support device, and the raw material is ejected after the water film is formed. It is a means for solving the problem.

[0005]

According to the present invention, two running wires are curved and supported, and a wedge space narrowing with the running of the wires is formed between the two wire surfaces by the support. An opening for water injection is formed in a wide portion of the wedge space and near the tip of the curved outer support. Further, in the above configuration, a water film having a thickness of 1 mm or more is formed on the wire by injecting water from a support water injection hole on the outside of the curve into a wide portion of the wedge space, and the raw material is placed thereon to form a narrow curved portion of the wedge space. Introduce. As a result, even a raw material having a high fiber concentration is sandwiched between the two wires without impairing the easiness of movement of each fiber, and a centrifugal force acts due to the bending of the two wires. The fiber concentration can be gradually increased without impairing the fiber dispersion to the outside, the impact on the raw material is small, and the action time is long, so that a fiber mat with a good fiber dispersion state can be formed.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an embodiment of the present invention; FIG. First, FIG.
1 is a first embodiment according to the present invention, and FIG. 2 is an enlarged view of a main part of FIG. In FIG. 1, 4 is a head box, 5, 6
Is a wire, 9 is a suction roll, 10 is a concave forming board as a wire support, 11a is a convex forming board as a wire support, 12 is a water injection hole, and water is injected from the water injection hole 12 toward the wire. You can do it. In the enlarged view of the main part of FIG. 2, the concave forming board 10 with water injection holes and the convex forming board 11a have a structure that does not provide a dewatering function. The shape is such that it becomes narrower on the exit side opposite to the side. In the first embodiment, the raw material spouted from the head box 4 is supplied with two wires from the position of the water injection hole under the condition that the water film is formed on the wire from the water injection hole 12 of the concave forming board 10 with the water injection hole. Landing is performed at a position where the gap between 5 and 6 is narrowed, and sandwiched between the wires. Thus, in the conventional apparatus, where the concentration of the raw material concentration occurs, the raw material solution is diluted, and the fluidity of the fiber is remarkably improved, so that a good fiber dispersion can be obtained. After that, the raw material between the two wires passes between the concavely curved forming board 10 that is greatly curved and the convexly formed convex forming board 11a having a smooth convex surface, and is sent to a subsequent process.

At this time, centrifugal force acts on the raw material, and the concentration of the fiber mat solution becomes higher on the concave forming board side than on the convex forming board side. However, due to fiber concentration without dehydration, fiber aggregation (flock formation) becomes extremely light, and a fiber mat is formed with good fiber dispersion maintained. After that, the fiber mat structure is quickly fixed by rapidly dehydrating with a suction roll 9 or a suction box 3 which is a normal dehydrating device. It is desirable that the dehydrating equipment used here has a large dehydrating ability.

FIG. 3 shows a second embodiment according to the present invention. This embodiment is characterized in that the convex forming board 11b is formed to have a serrated projection. And this second
In the embodiment, the same or higher fiber dispersibility as that of the concave forming board side can be obtained also in the fiber mat layer of the convex forming board side. FIG. 4 shows a third embodiment according to the present invention, which is characterized in that the forming roll 11c is used on the curved convex forming board side. In the third embodiment, it is possible to speed up the running of the wire and significantly reduce the wear of the wire. FIG. 5 shows a fourth embodiment according to the present invention, which is characterized in that the suction roll 11d is used for a curved convex forming board portion. In the fourth embodiment, as in the third embodiment, it is possible to increase the speed of wire running and greatly reduce wire abrasion, and dewater the suction roll side having a low fiber concentration. Further, the speed of the wire running can be further increased.

[0009]

As described above, the formation of the formation by the conventional wire part is carried out in parallel with the dewatering operation, so that the effect is very small, and in some cases, may adversely affect the growing fiber mat. . Since the present invention is dispersed while maintaining fluidity as described in detail above,
The dispersing effect is significantly improved. The formation of the sheet sample obtained by the tester according to the present invention shows an effect equal to or higher than that of a commercially available high-quality paper (printing paper) even at a head box concentration of 1.4%. Also, even at a concentration exceeding 3%, the remaining shades (flock) are very blurred and soft, show a high degree of dispersion effect, and fibers that appear when the concentration is increased with the conventional wire part are produced. It won't be dirty. According to the present invention, since the fiber arrangement is arranged in the plane direction of the paper web, it is possible to obtain a strong plane-direction paper force even when operating with a high-concentration raw material. There is no disadvantage that the paper strength becomes extremely weak and causes a fatal defect. Further, the present invention has a significant feature in that concave surface support and water film formation are combined. That is, when forming a water film on the concave supporting surface co
By ejecting the raw material after the formation of the water film, the fibers and the filler in the raw material jet are subjected to a shearing force when they are pressed (settled) by a centrifugal force against a concave support surface that supports one wire in a curved manner. , The fibers disperse easily. Also, the raw material is diluted by the water film, and the effect is further increased.
Even in a high-concentration raw material, the easiness of movement of the fiber, in other words, the dispersibility of the fiber is not impaired. Furthermore, the present invention
By forming a water film on this curvature,
Dehydration from fiber raw material liquid is suppressed and specific gravity is heavy
Pulp fibers migrate inside the concave surface due to centrifugal force and
A layer is formed. Therefore, even for raw materials with high fiber concentration
Good fiber without compromising the ease of movement of individual fibers
A major feature is that the dispersibility is maintained.
It also has the novelty of the invention.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a paper layer forming apparatus according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part in FIG.

FIG. 3 is an enlarged view of a main part according to a second embodiment of the present invention.

FIG. 4 is an enlarged view of a main part according to a third embodiment of the present invention.

FIG. 5 is an enlarged view of a main part according to a fourth embodiment of the present invention.

FIG. 6 is a side sectional view showing a conventional double-wire type wire part.

FIG. 7 is a side sectional view showing another conventional double wire type wire part.

[Explanation of symbols]

 4 Head Box 5, 6 Wire 9 Suction Roll 10 Concave Forming Board 11a Convex Forming Board 12 Water Injection Hole

Claims (1)

(57) [Claims] In a paper machine provided with two wires running across a raw material, a supporting device for curving and supporting one of the wires in a concave shape is disposed in a raw material jet supply unit, and the raw material jet landing of the supporting device is provided. A water injection hole is formed on the concave support surface on the upstream side of the section to form a water film.
Twin wire paper machine, characterized in that the output.