JP2000170088A - Discharge of foreign matter scraped by doctor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge method for foreign substances scraped off by a doctor device that can efficiently discharge the scraped foreign substances. SOLUTION: In the doctor device 1, a compartment chamber 15 is formed by the cover 11 to cover the top edge 2a of the doctor blade. An impeller 14 that is rotated by the rotation of the roller 10 is arranged in this compartment chamber 15. When the foreign substance is scraped off, the impeller 14 is rotated with the roller 10 to convey the scraped-off foreign substance toward the edge of the compartment chamber 15, until the foreign substance is excluded outside. In this process, the driving mechanism only for the foreign substance exhaustion and the like become unnecessary, and the foreign substances can be efficiently exhausted without increased cost in no need of the enlargement of the installation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a doctor device used for scraping foreign matter adhered to the surface of a roll such as a paper machine roll, and more particularly, to a doctor device for removing scraped foreign matter from the roll surface to the outside. The present invention relates to a method for discharging scraped foreign matter of a doctor device for discharging.

[0002]

2. Description of the Related Art When foreign matter such as paper scum adheres to the surface of a paper machine roll used in a paper machine, problems such as breakage of the conveyed paper due to the foreign matter occur. In addition, when foreign matter adheres to the surface of the rolling roll for steelmaking, the foreign matter causes unevenness on the surface of the rolled steel. In order to avoid such adverse effects, the roll is provided with a doctor device for scraping foreign substances attached to its surface.

A doctor device includes a doctor blade which is pressed against the surface of a roll, a blade holder for rotating the doctor blade to a pressed position where the doctor blade is pressed against the roll and an open position which is separated from the roll, and a blade holder. It basically consists of a supporting doctor back. By pressing the blade edge of the doctor blade against the rotating roll surface with a constant pressing force, foreign substances such as paper residue adhering to the roll surface can be reliably scraped off.

Foreign matter such as paper scraps scraped off from the surface of the roll accumulates on the blade edge of the doctor blade and on the surface of the roll against which the blade is pressed. If a large amount of foreign matter accumulates in such a part, a part of the foreign matter may enter between the cutting edge and the roll surface and be clogged there. If such a situation occurs, the performance of scraping foreign matter by the doctor blade is undesirably reduced.

Therefore, conventionally, an operator periodically cleans foreign matters such as accumulated paper residue from the blade edge portion and the roll surface in order to remove the foreign matters such as accumulated paper residue. Alternatively, the foreign matter is removed by periodically moving the foreign matter suction nozzle along the blade edge of the doctor blade. Alternatively, a compartment is formed to cover the blade edge portion of the doctor blade, and an air flow or a water flow is formed therein to discharge the scraped foreign matter to the outside from the edge of the doctor blade in the blade width direction.

[0006]

However, the method of removing foreign matter by hand has the drawbacks that the efficiency is low and that foreign matter cannot be removed during rotation of the roll. In addition, the method using a foreign matter suction nozzle requires a driving mechanism for moving the nozzle, and thus has the disadvantage that the apparatus becomes larger and the manufacturing cost increases accordingly. Similarly, in the method of forming a compartment and discharging foreign matter to the outside using an air flow and a water flow, a mechanism for guiding air and water from an air supply source or a water supply source using a hose or the like is required. is there. Depending on the installation location of the doctor device, such piping may not be able to be routed, and there is a disadvantage that the arrangement of such a supply pipe increases the size of the device and increases the manufacturing cost.

SUMMARY OF THE INVENTION An object of the present invention is to propose a method of discharging scraped foreign matter of a doctor device capable of discharging foreign matter with a small, compact and inexpensive structure without requiring a power source. .

[0008]

In order to solve the above-mentioned problems, according to the present invention, a blade of a doctor blade is pressed against a roll surface of a paper machine roll or the like and scraped off from the roll surface by the doctor blade. In the method of removing scraped foreign matter of a doctor device for discharging foreign matter in the blade width direction of the doctor blade, the scraped foreign matter is discharged to the outside as follows.

First, a compartment is formed along the blade width direction of the doctor blade to cover a surface portion of the roll against which the blade edge of the doctor blade is pressed. Then, by disposing an impeller extending in the blade width direction of the doctor blade in a state in contact with the surface of the roll in the compartment, the impeller is rotated by the rotating roll. Foreign matter scraped off from the surface of the roll by the rotating impeller is transported in the blade width direction of the doctor blade in the compartment, and is discharged to the outside from the end in the blade width direction.

Here, as the impeller, a blade having spiral blades formed in the blade width direction of the doctor blade can be used. A brush can be used as the spiral blade.

In the method for discharging scraped foreign matter of the doctor device according to the present invention, the impeller is rotated by the rotation of the roll to be scraped as a drive source, and the foreign matter is discharged to the outside by the rotation of the impeller. Therefore, the foreign matter can be discharged to the outside without the need to separately provide a drive mechanism for driving the impeller for discharging the foreign matter. Therefore, foreign substances can be discharged to the outside without increasing the size of the apparatus and without increasing the manufacturing cost.

Further, since the blades of the impeller are mechanically brought into contact with the roll surface and the blade edge of the doctor blade, the discharging operation of foreign matters can be performed more efficiently and reliably than in the case of using an air flow or a water flow. be able to.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a doctor device to which the method of the present invention is applied will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a cross-sectional configuration of the doctor device of the present embodiment, and FIG. 2 is a view as viewed from the direction of arrow II in FIG. With reference to these drawings, the doctor device 1 of the present example is
The doctor blade 2 has an elongated rectangular doctor blade 2 having a cutting edge 2a pressed against the blade a, a blade holder 3 holding a base end side of the doctor blade 2, and a doctor back 4 supporting the holder 3. ing.

The doctor back 4 is supported via a bearing on a side of a fixedly arranged pedestal (not shown) with journal shafts 4a attached to both ends thereof rotatable. A turnbuckle (not shown) is connected between the doctor back 4 and the gantry, and by adjusting this, the posture of the doctor back 4 can be adjusted to an arbitrary turning angle and fixed. .

The blade holder 3 is supported by the doctor back 4 so as to be rotatable about the connecting rod 3a. A tube 5 for opening the blade is arranged on the front side of the connecting rod 3a, and a tube 6 for pressing the blade is arranged on the rear side. These tubes 5,
6 is formed of a flexible material, and when the tube 5 side is expanded, the blade holder 3 holding the doctor blade 2 separates the doctor blade 2 from the surface 10a of the roll 10 around the connecting rod 3a. Swing in the direction, that is, the opening direction. When the other tube 6 is inflated, the blade holder 3 turns in the direction in which the doctor blade 2 is pressed against the surface 10a of the roll 10, that is, in the pressing direction.

The above configuration is the same as that of a commonly used doctor device, and further description will be omitted.

Here, in the doctor device 1 of the present embodiment, a plastic cover 11 extending in the blade width direction of the doctor blade 2 is attached to the blade holder 3. The cover 11 has a cross-sectional shape in which the side of the roll surface 11a is open, and when the blade edge 2a of the doctor blade is pressed against the roll surface 10a, the doctor blade is formed by the roll surface 11a and the doctor blade 2. 2, it is possible to form a closed compartment 15 having a substantially circular cross section extending in the blade width direction. For example, it is desirable to attach a rubber contact member to the edge 11a of the cover 11 on the side that comes into contact with the roll surface 11a to enhance the sealing property.

Plastic end plates 12 and 13 are attached to both ends (ends in the blade width direction) of the cover 11, respectively. An impeller 14 is hung between these end plates 12 and 13 in a rotatable state. The impeller 14 of the present embodiment includes a rotating shaft 14a made of plastic and a blade 14b made of a brush spirally received on the outer periphery of the rotating shaft 14a.

When the blade edge 2a of the doctor blade is pressed against the roll surface 10a, the brush blades 14b of the impeller 14 are also pressed against the roll surface 10a with a predetermined pressure.

An operation of discharging the scraped foreign matter in the doctor device 1 having the above configuration will be described. When the blade edge 2a of the doctor blade 2 is pressed against the surface 10a of the rotating roll 10, the blade edge 2a of the doctor blade 2
Foreign matter adhering to the roll surface 10a is scraped off.
The scraped foreign matter accumulates on the upper surface of the blade portion of the doctor blade, on the roll surface in the rotation direction closer to the pressing position of the blade edge 2a.

Here, at the time of scraping such a foreign substance,
The compartment 11 is formed by the cover 11. The impeller 14 disposed inside the compartment 15 is rotatable, and its brush blade 14b is pressed against the roll surface 10a. Therefore, at the time of scraping foreign matter, the impeller 14 is rotated by the roll 10, and the scraped foreign matter is transported in the blade width direction of the doctor blade by the spiral brush blade 14b.
The brush blade 14b performs an operation of wiping the blade edge 2a of the doctor blade and the roll surface 10a.

As a result, foreign matter is reliably removed from the blade edge 2a of the doctor blade and the roll surface 10a, and the removed foreign matter is removed from the end plate 12 or 13 located at one end in the blade width direction and the roll surface 10a. It is discharged outside from between.

As described above, according to the doctor device 1 of this embodiment, the compartment 11 is formed by the cover 11 so as to cover the blade edge 2a of the doctor blade, and the impeller 14 arranged inside the compartment 15 is By rotating using the rotation of the roll 10, the scraped foreign matter is discharged to the outside. Therefore, there is no need to arrange a dedicated drive mechanism or the like for discharging foreign matter, so that the scraped foreign matter can be efficiently discharged to the outside without increasing the size and cost of the apparatus.

Further, since the blade edge portion and the roll surface portion of the doctor blade are constantly wiped off by the brush blades 14b, foreign matters can be reliably removed from these portions and discharged to the outside.

(Other Embodiments) In the above example, a plastic screw can be used as the impeller 14 instead of the brush. Further, a screw made of a soft metal material can be used.
The soft metal material means a material whose hardness is sufficiently lower than the hardness of the roll surface.

The blades formed on the impeller 14 may be formed over the entire width in the axial direction, but may be formed only at both ends.

Further, a fluid circulation path for supplying water or air to the compartment 12 from one end and discharging the water or air from the other end may be formed. For example, when air is supplied, when using brush blades, there is an advantage that foreign substances clogged there can be discharged to the outside (brush clogging prevention).

The supply of the fluid is performed by the impeller 1
The rotary shaft 14a of 4 may be a hollow pipe, and a supply port opened at the end may pass through the hollow pipe, and may be blown into the compartment from a blowout port formed at a predetermined interval in the hollow pipe.

On the other hand, in the above example, the cover is made of plastic, but it goes without saying that other materials may be used. The sectional shape of the compartment may be a shape other than a circle, a rectangle, or the like.

[0031]

As described above, according to the method for discharging scraped foreign matter of the doctor device of the present invention, the impeller is rotated by using the rotation of the roll to be scraped, and the rotation of the impeller causes The scraped foreign matter is discharged to the outside. Therefore, according to the present invention, there is no need to arrange a drive source dedicated to scraping foreign substances, so that the scraped foreign substances can be efficiently discharged to the outside without increasing the size and cost of the apparatus.

Further, since the impeller mechanically hits the roll surface and the blade edge of the doctor blade, foreign matters can be reliably removed from these parts and discharged to the outside as compared with the case where a fluid is used.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a cross-sectional configuration of a doctor device to which a method of the present invention is applied.

FIG. 2 is a view of the doctor device of FIG. 1 as viewed from the direction of arrow II.

[Explanation of symbols]

 Reference Signs List 1 doctor device 2 doctor blade 2a blade tip 3 blade holder 4 doctor back 10 roll 10a roll surface 11 cover 12, 13 cover end plate 14 impeller 14a rotation axis 14b brush blade 15 compartment

Claims (4)

[Claims] 1. A doctor device for pressing a blade of a doctor blade against a roll surface of a paper machine roll or the like and discharging foreign matter scraped from the roll surface by the doctor blade in a blade width direction of the doctor blade. In the method for discharging foreign matter, a compartment is formed along the blade width direction of the doctor blade to cover a surface portion of the roll on which the blade edge of the doctor blade is pressed, and the blade of the doctor blade is provided in the compartment. By disposing an impeller extending in the width direction in contact with the surface of the roll, the impeller was rotated by the rotating roll, and was scraped off from the surface of the roll by the rotating impeller. Foreign matter is conveyed in the compartment width direction in the blade width direction of the doctor blade, A method of discharging foreign matter scraped off by a doctor device, characterized in that the foreign matter is discharged. 2. The method according to claim 1, wherein the impeller has blades formed spirally in a blade width direction of the doctor blade. . 3. The method according to claim 2, wherein the spiral blade is formed of a brush. 4. A doctor device for discharging scraped foreign matter by the method according to claim 1. Description: