JPH0588290B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to prevention of meandering during conveyance of a belt-shaped article, such as a strip.

[Conventional technology]

As a conventional meandering correction technique, one that utilizes the thread winding effect of the convex crown roll 1 as shown in FIG. 4 is known. This is easy, but
The meandering correction ability is small, and in order to increase the meandering correction ability, it is necessary to increase the crown amount. However, when the crown amount is increased for particularly soft band-shaped material 2,
There is a limit to the amount of crown, since buckling may occur and cause deterioration of product quality and threadability.

Methods for forcibly correcting meandering include a method of tilting and moving the conveyor roll 3 as shown in Figures 5a to 5c, a method using a meandering correction device as shown in Figure 6 (Japanese Utility Model Publication No. 50-3904), etc. There is.

The former is a method in which the traveling direction of the strip 2 is changed by setting an angle between the roll shafts 4. However, the fifth
As shown in Figures a to 5c, the path length l differs, for example, from l ₁ to l ₂ , depending on the position in the lengthwise direction of the roll body, and the strip 2 is locally pulled, especially when the strip 2 is soft. Wrinkles (backling) occur when the board is threaded.
There is a drawback that it tends to cause generation and shape defects.
Regarding the latter, the meandering is corrected by generating a tensile force in the width direction of the strip 2 due to the difference in vectors between the circumferential speed of the meandering correction roll 5 and the plate speed.
In this method, slipping occurs between the meandering correction roll 5 and the strip 2, which tends to cause eaves.

There is also another meandering correction method using suction force as shown in FIG. 7 (Japanese Patent Laid-Open No. 60-21332).

[Problem that the invention seeks to solve]

Although these proposals have been made, when conveying a strip, the threading speed may change suddenly depending on the circumstances of the preceding and following processes, or the strip itself may be wide or narrow. In addition, if the strip is made of a continuously annealed soft material, or if it is a thin strip with a thin plate, for example,
The reality is that the meandering correction has not always been completely satisfactory, and further study is required.

[Purpose of the invention]

An object of the present invention is to correct the meandering of a soft belt-shaped object to be conveyed without causing wrinkles (backling) or eaves.

[Means for solving problems]

The gist of the present invention resides in a method for correcting the meandering of a conveyed belt-shaped object by ejecting fluid onto the roll surface from a jet port provided in the body of the conveying roll to change the coefficient of friction on the surface of the conveying roll.

The present invention will be described in detail below based on one embodiment with reference to FIGS. 1, 2, and 3.

In FIG. 1, reference numeral 6 denotes a transport roll, and its body 7 is provided with a large number of ejection ports, for example, small holes 8. The conveying roll 6 is hollow, and has a partition 9 inside, and both sides are independent spaces. The body 7 has a large number of small holes 8 penetrated from the inside described above, from which fluids such as N ₂ , H ₂ , gases such as air, and liquids such as air and water are spouted. There is. This may be a slit instead of the eyelet 8. A hole passes through the shaft 10 and supplies liquid into the roll 6 via a rotary joint 11. 12 is a fluid flow control valve;
In this embodiment, they are provided on both sides of the shaft 10, and their flow rates are independently controlled. Thus, fluid whose pressure is independently controlled is supplied into the transport roll 6 and ejected from the small holes 8 onto the roll surface, changing the coefficient of friction.

The profile of the body 7 of the transport roll 6 is the second
It may be a concave crown as shown in the figure or a convex crown as shown in FIG. 3.

The control mechanism for meandering correction is as follows.

Referring again to FIG. 1, 13 is a sensor for detecting the position of the strip 2. As shown in FIG. Reference numeral 14 denotes a belt-like object position control device, which receives a signal from the sensor 13 and outputs a control signal to a fluid flow rate control valve 12, which is an operating end, to control the flow rate of fluid supplied to the transport rolls 6.

Next, we will discuss the effect. When conveying the strip 2 through a tapered roll, the strip 2
It is a well-known fact that the phenomenon of creep creeping from the small diameter side to the large diameter side of the roll is a well-known fact. Therefore, in the concave crown roll a as shown in FIG. A tensile force F acts, and this force is expressed by the following equation (1).

F=πμσhB...(1) Here, μ: coefficient of friction between the roll and the strip, σ: tensile force per unit area of cross-section of the strip, h: Thickness of the strip B: Width of the tapered part.

Considering the concave crown roll shown in FIG. 2, when the strip 2 meanderes in the positive direction B (to the right) by ΔB, the tensile force F increases by ΔF, causing the strip 2 to meander further. That is, the concave crown roll itself does not have the ability to correct meandering. However, when the fluid is ejected from the roll body 7 as in the present invention, the friction coefficient μ
is reduced by Δμ, so if Δμ/μ>ΔB/B, the tensile force F is reduced, which can contribute to meandering correction. To be precise, when ΔB meandering occurs, the tensile force F on the opposite side (left side) decreases by ΔF, so when considered in total, the relationship Δμ/μ>2ΔB/B is the condition under which the meandering can be corrected by the present invention. It is a well-known fact that concave crown rolls are effective in preventing the occurrence of wrinkles (backling), so the present invention makes it possible to correct meandering without causing wrinkles (backling).

In the case of a convex crown roll (Fig. 3), equation (1) becomes as follows.

F=-πμhB (1') Therefore, even if the meandering amount increases by ΔB, the tensile force F decreases by ΔF, so the roll itself has the ability to correct the meandering. However, since the tensile force F acts in a direction that compresses the strip 2, it causes wrinkles (backlinks). For example, if the strip 2 meanderes by ΔB in the positive direction of B (right side), if fluid is ejected from the roll surface on the opposite side (left side), the compressive force will be
Since F ₂ decreases due to a decrease in the friction coefficient μ,
It is possible to prevent the occurrence of wrinkles (backlinks). Furthermore, the effect of reducing the compressive force F ₂ due to the reduction in the friction coefficient μ is combined to increase the meandering correction ability.

〔Effect of the invention〕

As described above, the present invention makes it possible to correct meandering without causing wrinkles (backlinks) or eaves by ejecting fluid from the surface of the conveying roll and changing the coefficient of friction. Become. The effect is particularly great when applied to continuous annealing where a wide strip of soft and thin material is passed through.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of an apparatus for carrying out one embodiment of the present invention, Fig. 2 is a front view showing the force exerted on the strip by the tapered part of the concave crown roll, and Fig. 3 is the tapered part of the convex crown roll. Fig. 4 is a front view of a convex crown roll used in the conventional meandering correction method; Fig. 5a is a front view showing the force exerted on the strip material;
5b and 5c are a front view and a perspective view showing another conventional meandering correction method, and FIGS. 6 and 7 are a plan view and a front view showing another conventional meandering correction method. 1... Convex crown roll, 2... Band-shaped object, 3...
... Conveyance roll, 4 ... Roll axis, 5 ... Meandering correction roll, 6 ... Conveyance roll, 7 ... Body, 8 ...
... Hole, 9 ... Partition, 10 ... Shaft, 11 ... Rotary joint, 12 ... Flow rate control valve, 13 ... Position sensor, 14 ... Position control device.

Claims (1)

[Claims] 1. When a belt-shaped object is run on a conveyor roll, the inside of the body of the conveyor roll is partitioned into a plurality of independent chambers in the roll axis direction, and fluid is ejected from a spout provided on the surface of each body. A method for correcting meandering of a belt-like object, which comprises changing the coefficient of friction in the roll axis direction by adjusting the amount of ejection to correct the position of the belt-like object being conveyed.