JPH07157993A - Sieving machine - Google Patents

Abstract

PURPOSE:To provide a screening cylinder capable of performing a treatment regardless of the kind of raw material waste paper or the kind of the final product without requirement of exchange and enabling improvement in cost reduction of equipment and productivity. CONSTITUTION:This is related to a sieving machine equipped with a pressure- type slit screen. This sieving machine is equipped with a slit width control unit made up by fixing a longitudinally stretchable joint bar 24 to a screening member 21 which is prepared by making a slit opening 27 in each cylinder and putting the cylinders in layers or making a spiral slit in cylinders and capable of arbitrarily changing the opening dimension of the slit by stretching or contracting this joint bar 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wide range of industrial applications such as water treatment and wastewater treatment, and more particularly to a sieving apparatus for removing foreign substances used in the manufacturing process of paper pulp.

[0002]

2. Description of the Related Art A pressure type slit screen conventionally known as a sieving apparatus used in a paper pulp manufacturing process has mutually elongated circular cores having elongated slit-shaped openings as shown in FIGS. It has an inner screen cylinder 1 and an outer screen cylinder 2 which are spaced apart by. In such a conventional sieving apparatus, the stock material fed from the pump flows in from the inlet portion 3 to the flow path 4 surrounding the outer periphery, and the heavy foreign matters such as metal pieces and sand in the stock material are removed. It is discharged to the outside of the system from the trap 5 provided in the tangential direction opposite to the inlet portion 3 by the centrifugal force. Further, the stock material circulating in the flow path 4 is the screen cylinder 1,
In the process of entering the annular screening chamber 7 formed by 2 from the upper side in the direction indicated by the arrow 6 and flowing downward, some pass through the inner screen cylinder 1 and the other pass through the inner screen cylinder 1, and the other pass through the outer screen cylinder 2. Then, they are filtered and sorted to the outside, merged, and discharged from the outlet 8.

On the other hand, foreign matters such as plastic binding fibers and wood chips having a size that cannot pass through the screen cylinders 1 and 2 flow down through the screening chamber 7 and a tailing gutter 9 is provided.
It is discharged from the reject outlet 10 via the. Further, the rotary blade 12 suspended from the upper portion of the main shaft 11 and driven by the electric motor 13 continuously rotates at a high speed along the screen cylinder surface to agitate the stock material, so that foreign matter trapped on the screen cylinder surface and It acts to remove the fiber clumps and constantly clean the screen cylinder, while at the same time collecting the fiber clumps (flocs) formed together and decomposing them by vigorous stirring to promote the flow of fibers through the screen cylinder.

The screen cylinder used in the conventional pressure slit screen as described above is, as shown in FIGS. 9 to 11, an example of the inner screen cylinder 1 in which the stock material flows from the outside to the inside. There is. The outer screen cylinder 2 is basically the same. In the figure, at the upper and lower ends of a cylindrical screen plate 14, taper rings 15 for mounting to the screen device main body are fixed and attached by taper pins 16. The screen plate 14 has a large number of slit openings 19 arranged substantially in parallel with the axis of the screen cylinder and arranged in the circumferential direction. Further, on the surface 17 of the screen plate 14 facing the screening chamber 7, there are slit openings 19 which are straight in the thickness direction of the screen plate 14 and which are separated by a predetermined dimension and are constituted by mutually parallel walls. Back surface 18 of plate 14
Is provided with a trough-shaped relief groove 20 having an opening size sufficiently larger than that of the slit opening 19.

[0005]

The size of the slit opening 19 of such a screen cylinder is an important factor directly related to the foreign matter removal performance, and is generally set slightly finer to the foreign matter size to be removed. Target. On the other hand, the fibers in the stock material are required to pass through the slit openings 19, but generally, when the dimensions of the slit openings become small, the passage of fibers is hindered. At the same time, if the size of the slit opening is made fine, the opening area per unit area decreases, so that the processing flow rate decreases when the passage speed of the stock material is constant. Therefore, it is necessary to comprehensively determine the size of the slit opening in consideration of the foreign matter removal performance and the processing flow rate of the stock material. For example, in the case of a pressure type slit screen used in used paper processing equipment, in the case of used corrugated paper and used magazine paper, the size of the slit opening is 0.3 mm to 0.
35 mm, 0.2 mm to 0.25 for newspaper and fine waste paper
Although mm is generally used, the size of the slit opening is finally determined by the quality and degree of inclusion of foreign matter in the raw material, the concentration of the raw material, and the required final product quality.

As for the screen cylinder, in addition to the structure shown in FIGS. 9 to 11, various structures and forms of the screen cylinder have been put into practical use. However, in all of them, the size of the slit opening is specified at the time of manufacture and changed thereafter. It is not possible. Therefore, when a plurality of used waste papers are used or the final product is not a single product, it is necessary to prepare screen cylinders with various opening sizes and replace them according to the processing conditions. And to replace it, it is necessary to release the screen device body,
The equipment will be stopped for several hours. Further, when the equipment cannot be stopped due to continuous operation, it is necessary to install a plurality of screen devices equipped with screen cylinders having different opening sizes and switch to the screen device to be used according to the processing conditions. As a result, equipment costs increase because multiple screen device bodies and screen cylinders are prepared, and production efficiency decreases due to equipment shutdown,
It is necessary to secure personnel for replacement of the screen cylinder and switching of the screen device, which causes a problem of increased operating cost. The present invention intends to solve the above-mentioned problems in the conventional sieving apparatus, and to provide a sieving apparatus capable of coping with these regardless of the type of raw material waste paper or the type of final product without replacement. is there.

[0007]

Therefore, according to the present invention, in a sieving apparatus equipped with a pressure type slit screen, a screen member is formed by stacking with a gap between the cylinders or by forming a spiral slit in the cylinder. To
An axially expandable and contractible connecting rod is fixed, and the connecting rod is expanded and contracted so that the slit opening size can be arbitrarily changed, and the slit opening size can be adjusted from the outside even during operation. Then, this is a means for solving the problems.

[0008]

According to the present invention, the connecting rods which can be expanded and contracted in the axial direction are fixed to the screen member which is formed by stacking the cylinders with a gap therebetween or by forming the spiral slits in the cylinders.
The structure that allows the slit opening size to be adjusted by expanding and contracting the connecting rod allows multiple screens to be handled with a single screen cylinder even when there are multiple used waste papers or a single final product. There is no need to prepare the cylinder. Further, by adopting a structure in which the size of the slit opening can be adjusted from outside the screen device during operation, the size of the slit opening can be adjusted to an optimum value without stopping the operation. Therefore, it is not necessary to install a plurality of screen devices.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments of the drawings. FIGS. 1 to 6 show the embodiments of the present invention. First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 5. Disk-shaped screen members 21 are stacked in a cylindrical shape and fixed by a connecting rod 24 which can expand and contract. Since the material of the connecting rod 24 is required to have a property that it is easy to expand with less permanent strain due to expansion and contraction, it is desirable that the material has a low longitudinal elastic modulus and has corrosion resistance to the raw material of the stock. Specifically, in addition to metal materials such as copper alloys and aluminum alloys, plastics can be applied. The screen member 21 and the connecting rod 24 can be fixed by various fixing methods according to their materials. However, when the screen member 21 and the connecting rod 24 are both metal materials, electron beam welding which causes less thermal deformation. Alternatively, a fixing method by laser beam welding is preferable. Further, both ends of the connecting rod 24 are firmly fixed to the screen end material 23 by means such as welding, and the screen end material 23 is attached to the taper ring 22 for mounting on the screen device main body through the adjusting screw 26. It is assembled with a structure that can move in the axial direction.

The taper ring 22 is supported by a frame 25. When the adjusting screw 26 is rotated in the direction in which the connecting rod 24 extends, the connecting rod 24 extends evenly, and the screen member 21 adjacent to each other and the screens at both ends are rotated. The size of the slit opening 27 in the direction perpendicular to the axis formed by the scrap material 23 and the screen member 21 becomes wider. When the adjusting screw 26 is rotated in the opposite direction, the connecting rod 24 is compressed and contracts, so that the size of the slit opening 27 is narrowed.
Since the reaction force due to the expansion and contraction of the connecting rod 24 acts on the frame 25, when the connecting rod 24 is adjusted in the extending direction, the frame 25 is compressed by the acting reaction force. Since the compressive deformation of the frame 25 at this time needs to be made as small as possible, the total axial rigidity of the frame 25 is preferably 10 times or more the total axial rigidity of the connecting rod 24. With the above structure and operation, the size of the slit opening 27 can be arbitrarily adjusted by rotating the adjusting screw 26. A rubber O-ring 34 is used for the purpose of preventing the stock material from entering the thread portion of the adjusting screw 26.

In the first embodiment, the inner screen cylinder in which the stock material flows from the outer side to the inner side is shown, but the same applies to the outer screen cylinder. Further, the disc-shaped screen member 21 and the screen end material 23 form a ring-shaped slit opening 27. However, by fixing the screen member 21 with a stretchable connecting rod 24 in a continuous spiral shape, a spiral shape is obtained. The slit opening 27 can be configured. In the first embodiment described above, in order to adjust the size of the slit opening 27, it is necessary to stop the screen device, remove the upper lid, and rotate the adjusting screw.

On the other hand, in the second embodiment of the present invention shown in FIG. 6, the lower screen end material 27 is firmly fixed to the screen device main body with bolts, and the upper screen end material 28.
Is attached to the upper lid 33 via the lifting rod 29 and the lifting ring 30.
It is fixed with an adjusting bolt 31 and an adjusting nut 32. Therefore, by rotating the adjusting nut 32 and moving the adjusting bolt 31 in the axial direction, the connecting rod 24 can be expanded and contracted to arbitrarily adjust the size of the slit opening. That is, in the second embodiment, the size of the slit opening can be adjusted by rotating the adjusting nut 32 even when the screen device is in operation.
The conventional pressure type slit screens shown in FIGS. 7 and 8 exemplify a structure in which two cylinders, an inner screen cylinder and an outer screen cylinder, are mounted, but the present invention can be applied to this conventional structure. Further, it can be easily applied to the structure of the inner screen cylinder alone or the outer screen cylinder alone. The axial direction of the pressure type slit screen is illustrated as a vertical axis, but it can be applied to a horizontal axis structure.

[0013]

As described in detail above, even if there are a plurality of used waste papers or the final product is not a single piece, the screen cylinder of the present invention is capable of arbitrarily adjusting the size of the slit opening. The wide range of screen cylinders can be used. Therefore, since it is not necessary to prepare a plurality of screen cylinders, the equipment cost can be reduced and it is economical.
Also, by making it possible to adjust the size of the slit opening from the outside, it is easy to adjust the size of the slit opening even during operation, without interrupting the operation Can be selected.
Therefore, it is not necessary to install a plurality of screen devices according to the type of operating conditions as in the past, and it is not necessary to switch the screen devices, so there is no need to secure personnel for operation, and it is economical, and Production efficiency is improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a screen cylinder according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of FIG.

3 is an enlarged view of part D of FIG.

FIG. 4 is a top view of FIGS.

5 is a sectional view taken along line F-F in FIG.

FIG. 6 is a vertical sectional view of a pressure type slit screen according to a second embodiment of the present invention.

FIG. 7 is a plan view of a conventional pressure type slit screen.

FIG. 8 is a side view of a partial cross section of a conventional pressure type slit screen.

FIG. 9 is a perspective view of a conventional screen cylinder.

10 is a sectional view taken along line AA of FIG.

11 is a sectional view taken along line BB of FIG.

[Explanation of symbols]

 1, 2 screen cylinder 21 screen member 22 taper ring 23 screen end material 24 connecting rod 25 frame 26 adjusting screw 27 slit opening 28 upper screen end material 29 lifting rod 30 lifting ring 31 adjusting bolt 32 adjusting nut 33 upper lid

Claims (2)

[Claims] 1. A sieving apparatus equipped with a pressure type slit screen, wherein cylinders are stacked with a gap between them and stacked, or a screen member made by inserting spiral slits into cylinders is provided with an axially expandable and contractible connecting rod. A sieving device equipped with a slit width adjusting device that allows the slit opening size to be arbitrarily changed by fixing and fixing the connecting rod. 2. A mechanism for adjusting the slit opening size from the outside even during operation is provided.
The described sieving device.