JPH0243154A - Fluid supporter for strip - Google Patents

Abstract

PURPOSE:To make a strip supportable in noncontact with a little discharge fluid by installing at least a row of fluid nozzles on the surface of a roll axial central part in the roll circumferential direction. CONSTITUTION:A rotary joint is installed in a shaft end of a roll 11, and a fluid is fed to a fluid nozzle 13 of this roll 11 from the outside via this rotary joint, spraying the fluid out of this hole 13. On the other hand, the fluid is also fed to an auxiliary fluid chamber 14 from the outside, spraying it out of its nozzle 15 as well. At this time, the fluid sprayed out of the fluid nozzle 13 of the roll 11 at the upper part goes down along a strip 12, but it is put back to the upper part by the fluid out of the nozzle 15, being spouted toward an upper part from a clearance between the auxiliary chamber 14 and the strip 12. Consequently, pressure in a roll winding part is keepable, and thereby the strip 12 is floated from the roll 11, thus the strip is supportable in a noncontact state with the roll 11.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is a method of moving a strip-shaped object (hereinafter referred to as a "strip") of metal, paper, plastic, etc. from upstream to downstream by repeating vertical or horizontal passes. The present invention relates to a device that uses fluid to support the strip in a non-contact manner when the strip is transported to the destination.

(Prior art) As a method of supporting the strip in a non-contact state, Jou
rnal of the iron and 5tee
l Institute (May.

1963, P401-408), the following two are shown as representative examples.

■ A device in which a large number of air bearings are arranged.As shown in FIG. 8, a large number of nozzle holes 2 having the shape shown in FIG. In this method, the strip 3 is supported and conveyed without contact. In addition, 4 in FIG. 8 is an air artificial piping.

This method is described as being impractical because increasing the tension of the strip requires a very large air pressure, and the strip has a large swinging motion.

However, as described in JP-A No. 62-167162, improvements have been made to the swinging of the strip for use with lightweight objects such as photographic film, photographic paper, and magnetic tape, which require small air ejection pressure. However, there are problems such as the number of nozzle holes being too large and the need for extremely high air jet pressure to support and convey the metal strip, making it uneconomical. This is because the idea of floating the strip using energy ejected from multiple air bearings is unreasonable.

■ Application of the hovercraft principle As shown in Figure 1O, slit nozzle holes 2' are arranged toward the inside of the strip 3 to be supported and conveyed, and jets from these slit nozzle holes 2' are made to collide with the strip 3. This method applies the hovercraft principle, which uses the cushion pressure generated in an area surrounded by a curtain of fluid to change the direction of the flow.

This method also basically supports the strip by converting the kinetic energy of the fluid into static pressure or dynamic pressure, so in order to avoid contact between the strips, the fluid pressure on the pressure receiving surface, that is, from 2° of the slit nozzle hole, In order to increase the injection pressure, it is necessary to increase the flow rate of the injection fluid, resulting in a very high running cost.

Note that measures to improve the problem of the floating height of the strip being different in the longitudinal direction have been disclosed in Japanese Patent Application Laid-open Nos. 139832-1983 and 142728-1982, but they basically require a large output. , it is economically unreasonable.

(Problems to be Solved by the Invention) In other words, in the conventional method described above, the kinetic energy of the fluid is converted into pressure to levitate the strip. It is bulky and inefficient.

■ On the other hand, it can be assumed that it would be more efficient to reduce the floating height, but in this case, dynamic pressure support would result in instability, resulting in swinging of the strip, contact, and flaws.

- Especially when considering air as a fluid, its density is low in high temperature areas, so if you try to support the strip, the jetting speed will exceed Matsuha's speed and it will make a lot of noise. Note that even at room temperature, the amount of ejection is large and the noise cannot be ignored.

The sound of the blower is also a problem.

■ Strip conveyance usually involves a meandering phenomenon, but it is difficult to prevent meandering with conventional methods.

■ There are strict restrictions on changing the strip width, making it impractical for lines where strip dimensions change frequently.

■ Because the conventional type is fixed, it is very difficult to thread the tip of the strip no matter what method you use, and it has drawbacks such as being unfinished industrially, but the biggest bottleneck is economic efficiency and threading. It is gender.

The present invention has been made in view of the above-mentioned problems, and provides a strip that is highly economical, compact, and stable, and can also prevent meandering of the strip, make it difficult to thread the tip of the strip, and eliminate problems. The purpose of the present invention is to provide a fluid support device.

(Means for Solving the Problems) In order to achieve the above object, a first strip fluid support device of the present invention is a device that winds a strip around a hollow roll and supports the strip while conveying the strip, The roller has at least one row of fluid ejection holes in the circumferential direction of the roll on the surface of the central portion in the axial direction of the roll, and the roll is configured to be able to rotate in forward and reverse directions and to be able to stop.

The second aspect of the present invention is to have an auxiliary fluid chamber facing the roll surface opposite to the strip winding surface of the roll, and to have at least one fluid ejection hole on the surface facing the roll. There is.

Furthermore, the third aspect of the present invention is that at least one fluid ejection hole is provided on the inflow side and/or outflow side surface of the strip opposite to the strip of the auxiliary fluid chamber.

Furthermore, the fourth aspect of the present invention is the above-described fluid support device for a strip, which is used for centering and preventing swinging of the strip facing the strip on the inflow side to the roll and/or the outflow side from the roll. It is constructed to be equipped with a fluid ejection nozzle for use.

In other words, the present invention does not levitate the strip by colliding fluid with the strip as in the conventional method, but levitates the strip by the pressure of the viscous fluid thin film.

That is, as shown in FIG. 4, fluid is pushed out from the jet port 23 in the center of the pressure chamber 22 at a pressure Po (pressure Pc), and the fluid flowing toward both ends of the strip 12 creates a pressure shell, and the end part is released at atmospheric pressure Pa.

When a viscous fluid flows along a solid surface, a frictional force proportional to the velocity gradient of the fluid is generated between the image surface and the fluid.

As a result, a pressure gradient (Pc-Pa)/(W/2) occurs (W is the width of the strip 12), and the fluid flows from the high pressure side to the low pressure side while causing a pressure loss. The present invention is based on the basic principle that the levitation force of the strip is obtained by integrating the pressure along the strip, and that even a strip under tension can be easily levitated. Therefore, the floating height h is much smaller than in the conventional method and the flow rate is also small.

(Function) Since the present invention has the above-described configuration, the strip can be supported without contact with a small flow of fluid.

In addition, the fluid jet nozzles provided on the inflow side and/or outflow side of the strip, and on opposite sides of the roll sandwiching the strip, are used to prevent the strip from meandering and to prevent the strip from swinging. work.

(Embodiments) The present invention will be described below based on embodiments shown in FIGS. 1 to 3 and 5 to 7.

FIGS. 1 and 2 show a first embodiment of fluid-supported fabrication of a strip according to the present invention. In the figures, 11 is a roll, and 12 is a strip that is wound around and supported by the roll 11. It shows.

Thus, in the circumferential direction of the central portion of the body in the axial direction of the roll 11, at least one fluid ejection hole 13 is arranged at a substantially equal pitch.
A column is opened and also a strip 12 of roll 11
An auxiliary fluid chamber 14 is provided close to the roll 11 on the side opposite to the winding surface.

At least one fluid ejection hole 15 is also provided in the substantially central portion of the surface of the auxiliary fluid chamber 14 facing the roll 11 .

The fluid ejection holes are provided in the center of the body in the axial direction of the roll, because when the strip is supported, the center in the width direction of the strip passes through the center of the roll. That is, it is sufficient if there is an ejection hole on the surface of the roll corresponding to the center of the width of the strip when the strip is supported.

In the fluid support device having such a configuration, a rotary joint 16 is provided at the end of the shaft of the roll 11, and the fluid ejection hole 13 is connected from the outside via the rotary joint 16.
The fluid is supplied to the pump, and the fluid is ejected from there at a pressure P1 as shown in FIG.

On the other hand, fluid is also supplied from the outside to the auxiliary fluid chamber 14 at a pressure P2, and the fluid is ejected from the fluid ejection hole 15.

Note that the strip 12 is wound around the roll 11 with a tension T. The angle of this winding is shown as 180@ in this embodiment, but it goes without saying that the angle is not limited to this.

Here, the pressure P of the fluid ejected from the fluid ejection hole 15.13! and P, must satisfy the condition p, >p. By doing so, no fluid is ejected from the unwound portions of the strip 12.

By the way, in the present invention, the fluid ejected from the roll 11 at the upper part descends along the strip 12.
Since the fluid ejected upward from the gap with the auxiliary fluid chamber 14 returns the strip 12 upward, the pressure of the roll can be maintained and the strip 12 can be levitated.

At this time, if the conveying speed υ of the strip 12 increases, fluid film breakage may occur at the entrance side of the roll 11 due to soil, but in this case, as shown in FIG. 3, the auxiliary fluid chamber 1
A fluid ejection hole 17 may also be provided on the side surface of 4, and fluid may be ejected from this also to prevent membrane breakage. The fluid ejection holes 17 may be provided only on the inlet side of the strip 12, but they may be provided on both sides to eject the fluid as in this embodiment.

Further, when the strip 12 has a camber, meandering occurs, so the strip 12 has a camber as shown in FIG.
For example, air nozzle 1 ejects air toward the width center of 2.
For example, the air nozzle 18 may be installed on the entrance side to prevent meandering.This air nozzle 18 can also prevent the strip 12 from swinging at the same time.

Note that the air nozzle 18 is not limited to the one installed on the inlet side as in this embodiment, but may be installed on the outlet side or both.

Moreover, an electromagnetic or mechanical device may be used instead of the air nozzle 18 as long as it can prevent the strip 12 from meandering and swinging.

Next, the results of an experiment using the apparatus of the present invention will be described.

Part 1) When using gas (air) as the fluid The fluid support device of the present invention was tested on the strip 12 threading line shown in FIG.

That is, the fluid support device shown in FIGS. 1 and 2 was attached to the position of the A roll shown in FIG. 5. At this time, roll 11
The body has an outer diameter of 10,100 mm and a body length of 300 mm, and there is one row of fluid jet ports 13 with a diameter of 0.3 tm in the center of the body.
were processed to be arranged substantially uniformly in the circumferential direction at a pitch of about 6flI11. Further, an auxiliary air chamber I4 is provided at the bottom of the roll 11, and the distance from the roll 11 surface is approximately 0.3.
tm and placed facing each other as shown in FIG.

One φ3 fluid spout 15 is provided in the center of the surface of the auxiliary air chamber 14 facing the roll 11. The rotation speed and direction of the roll 11 can be freely selected using a variable variable inverter, and the roll 11 can also be made non-rotating.

A test device as shown in FIG. 6 was prepared by using air as the fluid in the fluid support device of the present invention. In addition, the 6th
In the figure, 19 is a flow control valve, 20 is a pressure reducing valve, and 21 is a pressure gauge.

The strip 12 used is 0.1 m thick + s x width 250
It is a cold-rolled steel plate with a tension of σT = 0.1 to 5 kg/i.
Variable up to n''. Also, the speed is variable from lO to 200m/ll.
It is variable with l1n. Leading thickness 0.15w x width 230
A coil with a thickness of 0.1 mm and a width of 250 m is connected to a coil of M, and when the coil head is wound onto a reel, the strip tension is cl t = 1 kg/am'', V
=50a+pm - roll 11 and auxiliary air chamber 1 as constant
4 to P+=1.2 kg/cd, P, -1,4k
When air was blown out at a rate of g/cd, it was confirmed by the displacement meter 22 that the strip 12 was floating by an average of 0.5 am. Next, when the roll 11 was made non-rotating, the floating height increased slightly to 0.55ew, but no significant difference was observed in the conveyance phenomenon.

At this time, increasing P1 increases the levitation height.
It was also observed that as the tension was increased, the levitation height became smaller. As the speed υ increases from the above standard, the roll becomes 11.
It was found that the floating height h became smaller at both ends of the strip on the entry side, causing contact between the strip 12 and the roll 11.

Therefore, as shown in Fig. 3, from the side of the auxiliary air chamber 14, P, =
When air was blown out at 1.4 kg/cj, roll 1
1. Non-contact on the entry side was ensured. In addition, strip 12
Since the strip 12 meanders from side to side in the camber area, the air nozzle 18 shown in FIG. 7 is arranged as shown in FIG.
When using ee, the meandering amount of the camber part was 1/3 to 1
/4, and stable threading was possible.

In addition, in the above experiment, the average pressure was 1.25 to 1.5 kg/C.
When calculating the average flow velocity with TA and the average buoyancy height as 0.5 m, it becomes v = 7.1 to 21.2 m/sec.

From this state, adjust the flow rate control valve 19 to remove the strip 12.
When the feeding state of the strip 12 was observed, it was found that high frequency vibrations were generated in the strip 12 when the flow velocity exceeded a certain average flow velocity. If the average flow velocity is calculated from the data at this time with the average floating height set to 0.5 wa, it will be υ-50 to 59 m/sec.

Therefore, the average flow velocity in the case of gas needs to be 60 m/sec or less.

Part 2) When used as a submerged roll for electroplating A strip 12 having a width of 1850mm was supported via a submerged roll for electroplating having a roll diameter of 800M using the apparatus of the present invention having the configuration shown in FIG.

At this time, the rotation speed of the roll 11 is such that the circumferential speed is approximately 1 of the sheet passing speed.
/2, and the tension of the roll 11 is 5000 kgf on one side,
Assuming that the water pressure at the roll shaft is 1.5 to 3 kgf/c and the flow rate is 100 to 2001/min and the floating height is calculated as follows.

The strip contact length (circumferential direction) of the roll 11 is φ0.
8 m x 3.14/2~1.26 m Liquid flow rate is 0.
20rrf/m1n=3.33X10-'rrr/se
c (both sides) 0.10rrf/m1n=1.67X10
-'rrf/sec (both sides) Therefore, the flying height is 1
m (10-3 m), the liquid flow rate is 1.32 to 0.6
6m/sec, and the flying height is 0.5m (0.5XI
O-3m), the liquid flow rate is 2.65 to 1.32m/5
eC1 also has a flying height of 0.25mm (0.25X10
-'m), the liquid flow velocity is 15.29 to 2.65 m/s
It becomes ec.

Next, change the pump to increase the flow rate to 5001/s.
When the temperature was set at 3 to 4 kgf/cd, high frictional noise was generated and vibrations were generated in the strip.

At this time, the average calculated flow velocity is 6.6 m/sec for a buoyancy height of 0.5 tm. Therefore, the limit is 7m/
It is necessary to set it to sec.

In the case of the conventional submerged roll method (called zinc roll), ■ Since the zinc roll has a crown, strip 1
2 is not completely flat, causing plate warping and making it impossible to narrow the distance between the electrodes.

■ When the rotation speed of the zinc roll increases, the plating liquid is drawn to the strip 12 and spreads irregularly onto the strip 12.
and the zinc roll, the crown effect disappears, causing meandering, and the relative position of the electrode and strip 12 becomes unstable.

There is a problem. In contrast, in the fluid support device of the present invention, the above problems can be solved, and the distance between the electrode and the strip can be narrowed to significantly reduce the electric power consumption.

(Effects of the Invention) As explained above, the present invention is capable of preventing the meandering of the strip, making it easy to thread the tip of the strip, and supporting the strip stably in a compact and non-contact manner. This invention has the great effect of solving all the problems.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the first embodiment of the present invention, Fig. 2 is a perspective view thereof, Fig. 3 is a drawing similar to Fig. 1 of the second embodiment, and Fig. 4 is a detailed explanation of the invention. Figure 5 is an explanatory diagram of the installation position during testing of the present invention, Figure 6 is an explanatory diagram of the test equipment,
Figure 7 is an explanatory diagram of the air nozzle, (a) is a front view, (b) is a side view, Figures 8 to 10 are conventional explanations, Figure 8 is an explanatory diagram of the nozzle hole, and Figure 9 is an overall perspective view, and FIG. 1O is another explanatory view of the nozzle hole. 11 is a roll, 12 is a strip, 13.15 is a fluid ejection hole, 14 is an auxiliary fluid chamber, and 18 is an air nozzle for alignment and vibration prevention. Figure 1

Claims (4)

[Claims] (1) A device for winding a strip around a hollow roll to convey and support the strip, which has at least one row of fluid ejection holes in the roll circumferential direction on the surface of the central part in the roll axis direction, and A fluid support device for a strip, characterized in that the roll can rotate in forward and reverse directions and can be stopped. (2) A claim characterized in that the roll has an auxiliary fluid chamber facing the roll surface opposite to the strip winding surface of the roll, and has at least one fluid ejection hole on the surface facing the roll. 1. A fluid support device for a strip according to claim 1. (3) The fluid support device for a strip according to claim 2, characterized in that at least one fluid ejection hole is provided on the inflow side and/or outflow side surface of the strip opposite to the strip of the auxiliary fluid chamber. (4) In the fluid support device for a strip according to any one of claims 1 to 3, there is provided a fluid supporting device for aligning the strip and preventing swinging of the strip, which is opposed to the strip on the inflow side to the roll and/or the outflow side from the roll. 1. A fluid support device for a strip, comprising a fluid ejection nozzle.