JP2594876Y2 - Dryer canvas for papermaking - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION This invention relates to a dryer canvas used in a dryer part of a paper machine, wherein a shape of a side end face of the dryer canvas is suitable for detecting a displacement in a width direction during traveling by an ultrasonic sensor. It relates to a shaped dryer canvas.

[0002]

2. Description of the Related Art In a dryer part of a paper machine, a displacement of a running dryer canvas in a width direction is corrected.
A guide device is incorporated to stably drive the dryer canvas. In this specification, the term "dryer canvas" includes a needle canvas obtained by needling a web on a base cloth.

There are two types of guide devices: a contact type and a non-contact type. In the contact type, a plate-shaped member called a palm is arranged on the side of a dryer canvas so as to contact the ears of the dryer canvas, and the width of the dryer canvas is increased. When the palm is displaced in the direction, the palm is displaced, and the angle of the rotation axis of the guide roller that supports the dryer canvas is inclined according to the amount of movement, thereby returning the dryer canvas to the original traveling position.

In the non-contact type, a photoelectric sensor is used in place of the palm, and when the running position of the dryer canvas is deviated by a certain amount or more, its ear interrupts the optical path of the photoelectric sensor, and the signal is guided by the signal from the photoelectric sensor. The rotation axis of the roller is inclined in the same manner as described above, and the dryer canvas is returned to the original position. There are several prior applications using a photoelectric sensor, such as Japanese Patent Application No. 2-262253 and Japanese Utility Model Application No. 2-401646.

Further, as a non-contact type guide device replacing the photoelectric sensor, a device using an ultrasonic sensor has recently been proposed (Japanese Patent Application No. 4-308017). In this method, the distance to the dryer canvas is detected by an ultrasonic sensor in a non-contact manner, and the bias of the dryer canvas is detected by the ultrasonic sensor.

[0006]

In the contact type guide device using palm, since the palm and the ear portion of the dryer canvas are in contact with each other, the ear portion of the dryer canvas or the palm is worn out due to contact friction. Life is short.
In particular, recently, with the speeding up of paper machines, the progress of the abrasion has been accelerated.

[0007] Further, since the dryer canvas and the palm are in contact with each other, the material of the dryer canvas and foreign substances may be caught on the palm, which is an unstable factor in safety.

[0008] Even in a non-contact type guide device, when a photoelectric sensor is used, the surrounding environment of the paper machine is generally harsh. Particularly, in the dryer part, the photoelectric sensor may fail or malfunction due to high temperature and humidity. It was easy to occur and the practicality was low.

On the other hand, those using an ultrasonic sensor are practically high without being affected by the surrounding environment. However, the shape of the ear part of the dryer canvas which can be detected by the ultrasonic sensor was not sufficiently clarified.

This invention is intended to provide a drier canvas having an ear shape that can be reliably detected by an ultrasonic sensor.

[0011]

SUMMARY OF THE INVENTION The present invention is used for a dryer with a guide device that detects the side end surface of a running paper-making dryer canvas with an ultrasonic sensor and corrects a displacement in the width direction of the dryer canvas. The thickness of at least one of the ears is 0.1 mm
The paper dryer as described above, wherein the shape of the side end surface of the ear portion is a curved or flat end surface in which the angle between the tangent line and the vertical surface at two points 0.1 mm apart in the thickness direction is within 10 degrees, respectively. It is a canvas.

The end face is formed by welding the side end face of the dryer canvas, processing the resin, and further performing polishing.

[0013]

According to the present invention, since the end surface shape of the side surface of the dryer canvas is improved, the reflected wave that can be sensed by the ultrasonic sensor can be sufficiently returned to the ultrasonic sensor regardless of the vertical movement that may occur while the dryer canvas is running. Therefore, displacement of the dryer canvas in the width direction can be reliably detected.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 5, the guide device for stably moving the dryer canvas (10) is provided with a guide roller (12) for guiding the dryer canvas (10) and a swing arm (12) suspended from a stand (13). 14)
Push rod (16) provided on stand (13)
And a spring (17). The push rod (16) is pushed and pulled by the diaphragm (15).

The ears (1) of the dryer canvas (10)
The ultrasonic sensor (20) for detecting the displacement of 1) is installed on the side of the dryer canvas (10), and the ultrasonic waves emitted from the ultrasonic sensor (20) receive the ears (11) of the dryer canvas (10). ) So as to be in contact with the side end surface. In the embodiment, it is installed at a position about 150 mm away from the ear of the running dryer canvas (10).

When the dryer canvas (10) is displaced in the width direction, the ultrasonic sensor (20) controls the controller (2).
1) and the diaphragm (1) via the electropneumatic converter (22).
5) is operated to incline the guide roller (11) to return the dryer canvas (10) to the original position.

As shown in FIG. 1, the dryer canvas (10) guided as described above has at least a side end face (11a) of the ear (11) on the sensor side as shown in FIGS. It is formed in a suitable shape. For example, in FIG. 2, the side end surface (11a) is formed as a vertical surface. In FIG. 3, the side end surface (11a) is inclined.
In FIG. 4, the side end surface (11a) is formed as a curved surface. Also, various thicknesses of the dryer canvas (10) are manufactured.

In order to form the side end face (11a) at a vertical plane or at a predetermined angle from the vertical plane, for example, when high precision is required, (a) the dryer canvas (1)
0) a method of welding and molding the ears (11), (b) a method of molding the resin by processing the ears (11), and (c) a molding of resin on the side end surface of the ears (11). There is a method of fixing the plate. In the case where very high precision is not required, (d) a method of polishing the end face (11a),
(E) A method of fixing a flat yarn having a slope of not less than 0.1 mm and an end surface (short surface) of not more than 10 degrees to a vertical surface on a side end surface, and (f) a thickness of 0.1 mm on a weft yarn. (G) When a round yarn is used as the weft, the resin is cut in the length direction so that the thickness becomes 0.1 mm or more, and (h) warp, single yarn is used. There is a method in which the yarn is cut to a length of 0.1 mm or more in the length direction, and then processed with a resin.

Also, the side end surface (11a) is formed into a curved surface by (a) a method of forming a curved surface by welding with a trowel to the ear (11), and (b) forming a curved surface by resin processing. (C) a method of fixing a round or semicircular yarn to the ear (11), and (d) a method of polishing the side end surface (11a) to a curved surface.

Dryer canvases having various thicknesses and short surface shapes were manufactured and tested, and the following results were obtained.

As shown in FIG. 6, the test apparatus holds a dryer canvas (10) having a width of 7 cm and a length of 15 cm so as to be able to move up and down, and 150 mm on the side of the dryer canvas (10).
An ultrasonic sensor (20) is installed at a remote position, and a signal from the ultrasonic sensor (20) is detected by a controller (21). The test was performed on a dryer canvas (1
0) is moved up and down with respect to the center line of the ultrasonic sensor (20), and the maximum detected vertical width (mm) (effective field of view) is measured.

The dryer canvas used as the sample is a warp
TM040 (polyester monofilament yarn 0.4m
mφ)

Weft TM050 (polyester monofilament yarn 0.5 mmφ)

Density 84.2 warps / 2.45 cm

Weft 17.2 × 2 yarns / 2.54 cm

The double weave of the above is used.

As shown in FIG. 7, the sample 1 has a thickness of 2.0 mm and a side end surface formed as a vertical surface. Sample 2 has a thickness of 2.0 mm and a side end surface formed in a semicircular shape. Samples 3 to 5 have a thickness of 2.0 mm and have side end surfaces inclined at 10, 15, and 30 degrees from the vertical plane, respectively. The sample 6 has a thickness of 2.0 mm, and has a shape in which the side end surface is pointed up and down by 45 degrees from the center. Samples 7 to 10 were formed with a polyester film having side end surfaces formed on a vertical surface and having thicknesses of 1.0 mm and 0.5 m, respectively.
m, 0.07 mm.

As a result of the test, the effective visual field (mm) in each of the samples 1 to 10 was 71, 65, 5 and 5 as shown in FIG.
9, 25, 25, 23, 63, 62, 62 and 4.

When the ultrasonic sensors are used to detect the samples 1 to 10 from a position 150 mm apart, the effective field of view varies, but all are detected. However, the displacement of the dryer canvas in the guide device of the paper machine is 20 mm above and below the standard position in consideration of safety.
Becomes Therefore, the effective visual field detected by the ultrasonic sensor (20) needs to be 40 mm. Therefore, Samples 1 to 3 and Samples 7 to 9 have an effective visual field of 40 mm or more and can be applied, but the remaining Samples 4 to 6 and Sample 10 have an effective visual field of 40 mm.
mm or less, it cannot be applied. Therefore, the dryer canvas must have a thickness of 0.1 mm or more.

It is conceivable that the dryer canvas is displaced 30 mm to the left and right from the standard position. When the effective field of view is 40 mm, the angle between the end face of the dryer canvas (10) and the vertical plane is equal to that of the dryer canvas (10). If the thickness is ignored, theoretically the standard position (150mm position)
When the dryer canvas (10) comes closest to the ultrasonic sensor (20) and reaches the maximum angle (at a position of 120 mm), it becomes 9.46 degrees, and if the thickness is taken into consideration, up to about 10 degrees is detected. It becomes possible. Therefore, it is desirable that the angle of the end face be within 10 degrees from the vertical plane.

[0032]

According to the present invention, if displacement is measured from the side by an ultrasonic sensor with respect to a side end surface formed into a predetermined shape of a papermaking dryer canvas, the widthwise direction of the running dryer canvas can be obtained. Can be detected. As described above, the displacement of the dryer canvas can be measured in a non-contact manner by the ultrasonic sensor, so that the dryer canvas does not wear out, and the conventional method does not cause the dryer canvas to come into contact with the palm as in the related art, thereby improving safety. Become. Also, reliable detection by the ultrasonic sensor becomes possible, the detection accuracy is high even under severe conditions of high temperature and high humidity, the running of the dryer canvas in the paper machine is stabilized, and the operation efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a dryer canvas according to the present invention.

FIG. 2 is a sectional view showing an example of a dryer canvas according to the present invention.

FIG. 3 is a sectional view showing another example of the dryer canvas according to the present invention.

FIG. 4 is a cross-sectional view showing another example of the dryer canvas according to the present invention.

FIG. 5 is a perspective view showing an example of a guide device for guiding the dryer canvas according to the present invention.

FIG. 6 is a side view showing a test apparatus.

FIG. 7 is a diagram showing a sample used in the test.

[Explanation of symbols]

 10 Dryer canvas 11 Ear 11a Side end face

Claims (1)

(57) [Scope of request for utility model registration] 1. A dryer canvas used in a dryer with a guide device for detecting a lateral end surface of a running papermaking canvas with an ultrasonic sensor to correct a displacement in a width direction of the dryer canvas, wherein at least one of the dryer canvases is used. The surface of the ear has a thickness of 0.1 mm or more, and the shape of the side end face of the ear is such that the angle between the tangent line and the vertical plane at two points 0.1 mm apart in the thickness direction is within 10 degrees, respectively. Or a papermaking dryer canvas with a flat end face.