JPH0316432B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a paper dust removal device for a doctor,
More specifically, the present invention relates to a small-sized, highly efficient paper dust removal device that can reliably remove paper dust, dust, etc. accumulated on each doctor etc. installed in paper making equipment.

[Conventional technology]

Removal of paper powder and dust that accumulates on the doctor or similar equipment such as a canvas cleaner (hereinafter simply referred to as the doctor) installed in papermaking equipment is an essential means for the operation of papermaking equipment and product quality. .

Conventionally, the above-mentioned paper dust has been widely removed by blowing it away with compressed air, or by manually suctioning it periodically with a vacuum cleaner or the like.

In addition, a suction device as shown in FIGS. 4 and 5 has been proposed in order to remove paper dust accumulated on the doctor by suction. In the apparatus shown in FIG. 4, paper powder accumulated on the tip of a doctor blade 402 attached to a doctor body 401 is installed at equal intervals in a chamber sealed by a hood 403 and a lip 404, and the doctor blade The paper dust is removed by suction by a plurality of nozzles 405 that move along the width of the paper 402 at preset time intervals.

The device shown in Fig. 5 is the doctor blade main body 5.
01 also serves as an exhaust pipe, and a plurality of orifices 503 are formed on the doctor blade 502 side at equal intervals (approximately 50 mm pitch) along the width of the doctor blade 502, and the orifices 503 are attached to the doctor blade 502. 50 foods that have been
The hood 504 has a suction port 505 formed in a slit shape over the entire width of the doctor blade 502 at the top of the doctor blade 502. By creating a negative pressure inside the doctor main body 501, the paper dust accumulated on the tip of the doctor blade 502 is removed by suction.

Conventionally, the method of blowing away paper powder with compressed air is not favorable in terms of the working environment, and the method of manually suctioning with a vacuum cleaner is complicated to remove paper powder from multiple doctor blades and has poor workability.

The devices shown in FIGS. 4 and 5 described above are all equipped with a suction port that is always open over the entire width of the doctor to suck paper powder from the entire width of the doctor. Therefore, it is difficult to obtain a uniform suction flow rate.

Figure 6 shows an example of suctioning paper dust using the device shown in Figure 4 or Figure 5, but the suction flow rate can vary between the suction end side and the opposite side of the entire width of the doctor. Because of the difference in formation, while paper dust can be removed on the suction side, it is difficult to completely remove it on the opposite side. Therefore, when the fan capacity is increased, the difference in suction flow velocity between the suction end side and the opposite side becomes even larger.

Not only that. In the apparatus shown in FIG.
Not only does this increase the variation in the suction flow velocity in the width direction, but also the hood 40
3 or lip 404 may be damaged.

Further, in the apparatus shown in FIG. 5 as well, pieces of paper are caught in the suction port 505 when the paper is cut, and paper powder accumulated in the partition of the orifice 503 gradually grows, causing a partial blockage. In particular, wet paper powder cannot be used because of the excessive accumulation of paper powder.

[Problems to be solved by the present invention]

In conventional devices, the suction part for paper powder is integrated with the doctor body, so it is not easy to install.

Uniform suction force in the longitudinal direction of the doctor surface cannot be secured.

When a piece of paper gets caught or a paper powder jam occurs, the operation is stopped, requiring time and effort to restore the system, and there is a risk of damage to the suction section.

There are drawbacks such as.

The object of the present invention is to improve the above-mentioned conventional drawbacks and provide a small, energy-saving device that can reliably remove paper dust.

[Means for Solving the Problems] The present invention has a fixed outer cylinder attached adjacent to the tip of a doctor blade of paper making equipment, and a rotatable and hollow inner cylinder inside the fixed outer cylinder. A tube is attached to the fixed outer tube, and a slit-shaped opening is formed in the fixed outer tube close to the doctor blade and over the entire width of the doctor blade.
On the other hand, a plurality of suction ports are formed on the outer circumferential surface of the inner cylinder and are arranged in a spiral along the axis of the inner cylinder,
This is a paper powder removal device for a doctor that is configured to rotate an inner cylinder and create a negative pressure inside the inner cylinder to suction and remove paper powder adhering to a doctor blade from a suction port.

[Effect]

The present invention is constructed as described above, and the fixed outer cylinder has a length that can cover the entire width of the doctor blade, and a slit-shaped opening is formed over the entire width of the doctor blade in a portion close to the doctor blade. has been done.

A rotatable and hollow inner cylinder is installed inside the fixed outer cylinder, and a suction valve is arranged in a spiral shape along the axis of the inner cylinder on the outer peripheral surface of the inner cylinder. A suction port is formed in the inner cylinder, and as the inner cylinder rotates, the suction port is arranged in a spiral pattern from one end of the suction port to the other end of the slit-shaped suction port of the outer cylinder. It is now possible to match.

That is, in the present invention, the slit-shaped opening formed in the fixed outer cylinder is sequentially aligned with one suction port by the rotation of the inner cylinder installed inside the fixed outer cylinder, so that the negative pressure inside the inner cylinder is reduced. The suction pressure is applied to the part where the two suction ports meet and does not work on the other suction ports, so the suction flow rate is high on the suction side and low on the opposite side, as in the conventional case. Non-uniformity does not occur, and the suction flow rate can be maintained at approximately the same rate over the entire width of the doctor blade.

Therefore, in the present invention, it is sufficient to use a suction pressure that is sufficient to remove paper powder using one of the plurality of suction ports formed in the inner cylinder, so that the power cost can be kept low.

In addition, the multiple suction ports of the inner cylinder are constantly moving inside the outer cylinder, so even if a piece of paper or paper powder gets stuck to the suction port, strong suction pressure will be applied to that part, so it will be easy to remove. Can be removed by suction. Note that the plurality of suction ports formed in the inner cylinder in the present invention may have a circular shape with a diameter equal to the slit width of the slit-shaped opening formed in the outer cylinder.
Preferably, it is an oval shape having the same direction and the same width as the slit of the outer cylinder.

Further, in the present invention, the distance between the fixed outer cylinder and the rotating inner cylinder may be approximately 0.05 to 0.1 mm. Also,
If necessary, the inner cylinder is divided into a plurality of parts in the axial direction on its outer periphery, and a split ring having a suction port formed at the same position as the suction port arranged in a spiral shape on the inner cylinder is fitted. It may be something you have.

〔Example〕

FIG. 1 shows one embodiment of the present invention, which will be described below based on the illustrated example. A slit-shaped opening 2 is provided on the outer peripheral surface of the outer cylinder 1 along the axis of the outer cylinder 1 and has the same length as the width of the doctor blade.
is formed.

An inner cylinder 3, which is rotatable around the axis of the outer cylinder 1 and has a hollow interior, is mounted inside the outer cylinder 1. On the outer peripheral surface of the inner cylinder 3, a plurality of slit-shaped suction ports 4 are arranged in a spiral shape in the axial direction.

Furthermore, a plurality of split rings 5 that are split in the axial direction are fitted onto the outer peripheral surface of the inner cylinder 3.
The plurality of divided rings 5 each have a suction port 6 formed in a portion corresponding to the plurality of suction ports 4 formed in the inner cylinder 3. However, in the present invention, the split ring 5 is not necessarily necessary, and the inner cylinder 3 may simply be attached.

FIG. 2 shows an example of the suction ports 4 and 6 formed in the inner cylinder 3 and the split ring 5, respectively, in a developed view. On the other hand, the length n in the axial direction of the suction port 6 is equal to the length l, and is arranged in a spiral shape on the outer peripheral surface of the inner cylinder 3. In addition, in the illustrated example, the suction port 6 formed in the split ring 5
As shown in FIG. 1, the opening is expanded toward the outer cylinder 1 side, but it is not limited to this, and may be the same size as the suction port 4 of the inner cylinder 3. . Further, the width of the slit of the suction port 4 is not particularly limited, but is approximately 8 to 12 mm, and the length n of the suction port 6 is approximately 150 to 350 mm.

FIG. 3 shows an example of the present invention installed in a paper machine, in which the outer tube 1 is suspended and fixed by an air cylinder 8 attached to a frame 7. Further, the slit-shaped opening 2 formed in the outer cylinder 1 is arranged at a position close to the doctor blade 9.

Further, one end of the inner cylinder 3 attached to the outer cylinder 1 is connected to a continuously variable transmission 11 via a universal joint 10, and an exhaust pipe 12 is connected to the other end.

The continuously variable transmission 11 is started to rotate the inner cylinder 3. The continuously variable transmission 11 has a speed of 7 revolutions/minute or less, and a normal motor capacity of 2 revolutions/minute is about 90W.

A plurality of suction ports 4 formed on the outer circumferential surface of the inner cylinder 3 by the rotation of the inner cylinder 3 are arranged in a spiral pattern from the suction ports 4 at one end to the suction ports 4 at the other end of the outer cylinder 1. The suction port 4 matches the slit-like opening 2 of the pump, and suction is carried out only through the matching suction port 4. Therefore, the suction pressure hardly changes between any of the suction ports 4, and approximately predetermined suction pressure and suction flow rate can be maintained. In addition, since the suction port 4 of the inner cylinder 3 constantly repeats movement from one end of the doctor blade 9 to the other as it rotates, the doctor blade 9 uniformly removes the paper powder by suction without leaving any partial paper powder. can do.

Further, according to the present invention, since the diameter of the outer cylinder 1 can be made relatively small, the apparatus can also be made small and compact.

Furthermore, in the present invention, most paper dust can be easily removed by appropriately changing the rotational speed of the inner cylinder 3 depending on the situation, such as whether dry paper dust, wet paper dust, or a large amount of paper dust is generated.

In addition, the present invention is not an integral structure with the doctor blade, but is attached separately, and the air cylinder 8
Since the doctor blade is suspended by the doctor blade, it is easy to remove and move, and therefore the doctor blade can be easily replaced, repaired, and repaired.

〔effect〕

As described above, in the present invention, a rotatable inner cylinder is mounted inside the outer cylinder, a plurality of suction ports are formed in a spiral shape on the outer peripheral surface of the inner cylinder, and the plurality of suction ports are sequentially opened as the inner cylinder rotates. Since it is aligned with the slit-shaped opening of the outer cylinder and suction can be drawn from the aligned suction port, the suction pressure can also be reduced. Furthermore, as the multiple suction ports repeatedly move from one end of the doctor blade to the other as it rotates, it is possible to maintain almost uniform suction pressure and suction flow rate over the entire width of the doctor blade, so there is no risk of paper dust remaining in some areas. do not have.

Further, by appropriately adjusting the rotation of the inner cylinder, paper dust can be reliably removed regardless of whether the amount of paper dust is dry, wet, or small.

Furthermore, since the present invention has a small and compact structure and is attached separately from the doctor blade, operations such as replacing and repairing the doctor blade can be facilitated.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an embodiment of the present invention, Fig. 2 is an example of a developed view of an inner cylinder and a split ring, Fig. 3 is an explanatory view of the present invention installed, and Fig. 4 is a conventional device. FIG. 5 is an explanatory diagram of one example, FIG. 5 is another explanatory diagram of a conventional device, and FIG. 6 is a graph of an example of suction flow rate versus doctor blade width of the conventional device. 1: Outer cylinder, 2: Opening, 3: Inner cylinder, 4: Suction port, 5: Split ring, 6: Suction port, 7: Frame, 8: Air cylinder, 9: Doctor blade, 11: Continuously variable transmission .

Claims (1)

[Claims] 1. A fixed outer cylinder is attached adjacent to the tip of the doctor blade of papermaking equipment, and a rotatable inner cylinder with a hollow interior is attached to the fixed outer cylinder. A slit-shaped opening is formed near the doctor blade and over the entire width of the doctor blade, and on the other hand, a plurality of openings are arranged in a spiral shape along the axis of the inner cylinder on the outer peripheral surface of the inner cylinder. What is claimed is: 1. A paper dust removing device for a doctor, characterized in that a suction port is formed therein, and paper dust adhering to a doctor blade is removed by suction by rotating an inner cylinder and creating a negative pressure inside the inner cylinder.