JP2851562B2 - Centrifugal 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 centrifugal papermaking apparatus for a papermaking machine.

[0002]

2. Description of the Related Art As a conventional papermaking method, for example, as shown in FIG. A jet is jetted onto the horizontally moving wire 3 as a three-dimensional jet to form a raw material layer 4. The water is gradually dehydrated through the voids or pressure is applied by the compressor 8 from the cylindrical fiber suspension jetting device 7 having the water jetting nozzle 6 in the initial region of the paper layer forming portion as shown in FIG. Guide 9
Water is supplied to the wire 10 and the felt 11 traveling with a curvature along the line, a water film is formed on the wire 10, and then the raw material is supplied onto the inner surface of the traveling wire 10 by the multi-tube nozzle 12 on the water film. Fibers form a paper layer that is fixed on the inner surface of the wire 10 by centrifugal force, the water in the raw material is dehydrated by centrifugal force, and then the raw material on the wire 10 is passed through the wire 10 by the vacuum box 13. I have.

[0003]

However, in the former method described above, the fiber concentration of the raw material supplied to the head box is usually about 0.3 to 1.2 wt%, and the fiber concentration higher than this fiber concentration is higher than 0.3 wt%. When the raw material is supplied, the agglomeration speed of the fibers in the raw material increases rapidly, and it becomes easier to form an aggregate called floc, because the floc forming speed is faster than the speed at which water is dehydrated from the raw material layer. is there. When flocs are formed in the raw material layer, the fiber network structure which influences the strength of the paper is coarsened, and the strength is significantly reduced.

[0004] In the latter, when the raw material is sprayed from the multi-tube nozzle onto the inner surface of the wire running with a curvature, the fibers in the raw material landing on the wire are aggregated to form flocs by the action of centrifugal force. Although the fiber network forms a dense low layer because it is fixed on the wire, the raw material has a relatively low concentration due to the force acting on the wire toward the center of rotation due to tension in the part where the wire travels with curvature. In this case, the force toward the rotation center due to the tension becomes larger than the reaction force due to the dewatering resistance, and the wire may move toward the rotation center. Therefore, in this apparatus, the usable raw materials are limited to the high-concentration raw materials. There is a possibility.

The present invention has been developed to address such a problem, and it is an object of the present invention to prevent a wire traveling with a curvature from moving toward the center of rotation even when a raw material has a relatively low concentration. .

[0006]

According to a first aspect of the present invention, there is provided a dehydration suppressing plate having a concave curved surface, a water supply hole provided upstream of the concave curved surface, and a concave curved surface of the dehydration suppressing plate. An endless wire running at a high speed along a wire, a raw material transfer wire running along an open roll rotating with a concave curved surface of the dewatering suppressing plate and a minute gap, and a head box for supplying a raw material liquid between the two wires. A pinch roller for holding the endless wire between upper and lower ends of the dehydration suppressing plate and preventing tension applied to the wire.

Further, the present invention provides a dehydration suppressing plate having a concave curved surface and having a water supply hole upstream of the concave curved surface, an endless wire running at high speed along the concave curved surface of the dehydration suppressing plate, and an inner surface of the endless wire. A head box for supplying a raw material liquid to the upstream side of the water supply hole, and clamping both end portions of the endless wire,
A chain gripper that runs on the same concave track as the inner surface of the dewatering suppression plate along a rail.

Further, the present invention provides a dewatering suppressing plate having a concave curved surface formed with a water supply hole upstream of the concave curved surface, an endless wire running at high speed along the concave curved surface of the dewatering suppressing plate, and an inner surface of the endless wire. A head box for supplying the raw material liquid to the upstream side of the water supply hole, a narrow conveying belt on which both ends of the endless wire are fixed and the wire runs, and an end portion on which the narrow conveying belt is wound and rotated. And a pulley.

[0009]

According to the present invention, when the raw material layer on the wire is exposed to the centrifugal force without being dewatered by the above-described means, the specific gravity of water and fiber in the raw material is different, so that the fiber having a higher specific gravity is used for the inner surface of the wire. Electrophoresis in the raw material. At this time, since a shearing force proportional to the migration speed acts on the fiber, a fiber mat layer is formed on the inner surface of the wire while maintaining a uniform dispersion state. Even if fiber flocks remain in the raw material jet ejected from the head box,
The floc is strongly pressed against the inner surface of the wire by centrifugal force. For this reason, the floc is deformed so as to be flat on the inner surface of the wire. Since this deformation includes both compression and shear deformation components, the flocs split and redisperse, and as a result, a dense fiber mat layer is formed on the inner surface of the wire.

[0010] The fiber mat layer on the wire maintains its form by centrifugal force during the dewatering suppression time. Immediately after the completion of the dehydration suppression, the moisture in the raw material layer is rapidly dehydrated by centrifugal force, and the fiber mat layer is immobilized before re-flocating to form a paper layer having a dense fiber network structure.

[0011]

FIG. 1 shows a first embodiment of the present invention. 20 in the figure
Denotes a dehydration suppressing plate, the dehydration suppressing plate 20 is formed in a concave curved surface, and a water supply hole 21 is provided on the concave curved surface, and an endless wire 22 running at high speed along the concave curved surface of the dehydration suppressing plate 20 is provided. To hold the endless wire 22
The pinch roller 23 for preventing tension applied to the ear
The pinch roller 2 is provided before and after the dehydration suppressing plate 20.
No. 3 shows that the wire length in the centrifugal force action area does not change with time.
The drive is controlled as
Endless wire 22 from the tension required to drive the wire
Be released.

A head box 25 for supplying a raw material liquid 24 is provided on the inner surface of the endless wire 22 on the upstream side of the water supply hole 21. The head box 25 supplies the raw material liquid 24 to the inner surface of the endless wire 22. Is sandwiched between pinch rollers 23. An open roll 29 having a water-permeable mesh surface is provided on the inner surface of the raw material layer 26 in order to further stabilize the running of the endless wire 22 and the raw material layer 26 in the centrifugal force action field, and is wound around the open roll 29 and conveyed. The raw material transfer wire 28 was brought into contact. In this case, since the raw material transfer wire 28 and the open roll 29 that are in contact with the inner surface of the raw material layer 26 are water-permeable, the movement of the fibers and moisture in the raw material layer 26 in the centrifugal force action field is not excluded.

FIG. 2 shows a second embodiment of the present invention, in which a running guide 30 is provided on the outer surface of the endless wire 22 and is fitted into a guide rail 31 provided on a concave curved surface of the dewatering suppressing plate 20. is there. FIG. 3 shows a third embodiment of the present invention, in which both ends of the endless wire 22 are clamped by a chain gripper 33 that moves along an arcuate rail 32, and the endless wire 22 travels in a circular locus. It is like that.

FIG. 4 shows a fourth embodiment of the present invention. A narrow conveying belt 34 is fixed to both ends of the endless wire 22, and the narrow conveying belt 34 is moved along an end pulley 35 and a guide roll 36. The endless wire 22 is caused to run on a concave surface by running. In the figure, 37 indicates felt, 38 indicates a pickup roll, and 39 indicates suction.

[0015]

As described above, according to the present invention, the endless wire is caused to run along the concave curved surface of the dewatering suppressing plate having a concave curved surface and having a water supply hole above the concave curved surface. Since the raw material liquid is supplied from the head box on the upstream side of the water supply hole and the endless wire is sandwiched between the upper and lower ends of the dewatering suppressing plate to prevent tension applied to the wire, the raw material concentration is 1.2 to 3 Even if the concentration is as low as 0.0 wt%, the endless wire does not move to the center of rotation, making it possible to make paper having a quality equal to or higher than that of the conventional papermaking method, and a higher dehydration efficiency than conventional papermaking by centrifugal dewatering. Thus, the subsequent steps can be omitted and simplified, and there are effects such as a reduction in dryer load and the like, and a reduction in running cost.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing a second embodiment of the present invention.

FIG. 3 is a perspective view showing a third embodiment of the present invention.

4A and 4B show a fourth embodiment of the present invention, wherein FIG.
(B) is a sectional view of a guide roll part, and (c) is a sectional view of a pulley part.

FIG. 5 is a system diagram showing a conventional example.

FIG. 6 is a system diagram showing another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 20 Dehydration suppression plate 21 Water supply hole 22 Endless wire 23 Pinch roller 24 Material liquid 25 Head box 28 Material transfer wire 29 Open roll 33 Chain gripper 34 Narrow belt for conveyance 35 End pulley

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Hiroshi Iwata, Inventor Hiroshima Research Center, Hiroshima Prefecture, Hiroshima Prefecture No. 6-22 Mitsubishi Heavy Industries, Ltd. Hiroshima Laboratory (56) References JP-A-51-67404 (JP, A)

Claims (3)

(57) [Claims] 1. A dehydration suppressing plate having a concave curved surface and having a water supply hole upstream of the concave curved surface, an endless wire running at high speed along the concave curved surface of the dehydration suppressing plate, and a concave curved surface of the dehydration suppressing plate. A raw material transfer wire running along an open roll rotating with a small gap, a head box for supplying a raw material liquid between the two wires, and holding the endless wire between upper and lower ends of the dehydration suppressing plate. A centrifugal papermaking device comprising a pinch roller for preventing tension applied to a wire. 2. A dewatering suppressing plate having a concave curved surface and having a water supply hole upstream of the concave curved surface, an endless wire running at high speed along the concave curved surface of the dewatering suppressing plate, and an inner surface of the endless wire. A head box for supplying the raw material liquid upstream of the water supply hole, and a chain gripper that clamps both ends of the endless wire and travels along a rail along a concave curved surface of the dewatering suppression plate along a rail. A centrifugal papermaking apparatus characterized by the above-mentioned. 3. A dehydration suppressing plate having a concave curved surface and provided with a water supply hole upstream of the concave curved surface, an endless wire running at a high speed along the concave curved surface of the dehydration suppressing plate, and an inner surface of the endless wire. A head box for supplying the raw material liquid to the upstream side of the water supply hole, a narrow conveying belt on which both ends of the endless wire are fixed and the wire runs, and an end on which the narrow conveying belt is wound and rotated. A centrifugal papermaking apparatus comprising: a pulley;