JP3511793B2 - Device for changing the direction of passing of strip material - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for changing the direction of passing a strip made of a cold-rolled steel sheet or the like, in which a running strip is wound helically. The present invention relates to a sheet passing direction changing device that changes a sheet passing direction in a non-contact state. 2. Description of the Related Art A so-called helical floater-type sheet passing direction changing device which wraps a running strip in a helical manner around a floater and changes the sheet passing direction in a non-contact state is known. Can be changed, and the degree of freedom in the sheet passing direction is greater than that in the bend floater type sheet passing direction changing device. [0003] For this reason, this kind of passing direction changing device is
In recent years, it has been adopted in various process lines. In particular, since continuous two or more steps have a great effect on labor saving and improvement of yield, a case where two processes having different extending directions of pass lines are continued. Is also increasing. The helical floater-type passing direction changing device is considered to be useful in that the passing direction of the band-shaped material can be changed without causing non-contact, that is, without causing scratches. [0004] Conventionally, as an apparatus for floatingly supporting a strip-shaped material such as a steel strip in a helical manner as described above and changing the passing direction in a non-contact state, for example, it is described in Japanese Patent Application Laid-Open No. 51-25274. Are known. As shown in FIG. 6 and FIG. 7, for example, this apparatus is provided with a cylindrical floater 50 and a gas having a predetermined pressure provided along a belt material winding position (passing position) L on the surface of the floater 50. And a plurality of guide holes 53 and 54 for guiding the strip 52 on the entrance side and the exit side of the strip 52 with respect to the floater 50, respectively. Is done. [0006] Then, the conveyed strip 52 is guided by the guide roll 53 on the entry side, and is moved to the floater 50.
Wound obliquely along the surface of the floater 50
While the passing direction is changed while passing along the
It is sent to the next process via the guide roll 54 on the exit side. [0007] At this time, the band-shaped member 52 wound around the floater 50 is floated and supported from the surface of the floater 50 by the gas ejected from the ejection holes 51, and moves in a non-contact state with the floater 50. [0008] However, in the above-described conventional passing direction changing apparatus, the band member 52 is wound around the floater 50, and is simply supported by the gas ejected. Therefore, for example, when the following passing conditions change, the floating amount of the strip 52 from the floater 50 changes. When a tension fluctuation occurs in the strip-shaped material due to acceleration or deceleration in a section including the passing direction changing device, a change in tension generated due to acceleration or deceleration in a section adjacent to the passing direction changing device. When the tension changes in the strip due to the propagation to the section including the plate direction changing device, when the thickness or the width of the strip 52 changes, and when the floating amount of the strip 52 fluctuates as described above. ,
The guide roll 53 on the entrance side and the guide roll 54 on the exit side
, The pass line length of the band-shaped material 52 changes, and the band-shaped material 52 at the outlet side position shifts in the plate width direction of the band-shaped material 52. The fluctuation in the sheet width direction due to the fluctuation of the flying height is caused by winding the belt-shaped material 52 in a helical shape at a predetermined spiral angle, and is specific to the helical floater type sheet passing direction changing device. is there. That is, when the flying height changes as described above,
Since the belt 52 is wound around the floater 60 in a helical manner, meandering or offset occurs in the belt 52, and the belt 52 is twisted or skewed due to the restraint by friction with the guide rolls 53 and 54. There is a problem that may occur. For example, when the flying height increases, meandering occurs as shown in FIG. In FIG. 8, Δh indicates a deviation from a target flying height, and ΔH indicates a meandering amount generated at that time and its direction. In addition to the meandering, skew occurs as shown in FIG. In FIG. 9, the alternate long and short dash line indicates a change in the position of the plate end in accordance with the shift of the band-shaped material 52. Here, in the conventional sheet passing direction changing device, in order to suppress the swing in the sheet width direction at the time of the above-mentioned sheet passing direction change,
For example, as described in Japanese Patent Application Laid-Open No. 4-55254, a side plate or the like that guides the strip 52 along the strip winding position (passing position) L on the surface of the floater 50 may be provided. When the band-shaped material 52 swings in the width direction of the plate, the band-shaped material 52 rubs against a side plate or the like, which causes the quality of the band-shaped material 52 to deteriorate. Conventionally, in a bend floater type sheet passing direction changing device, as described in Japanese Patent Application Laid-Open No. 2-204264, when a band-shaped material passes through a stepped point in order to adjust a floating amount. The bend floater type changes the passing direction in the same plane, and adds a `` twist '' to a strip like a helical floater type in the passing direction. Is not converted, the change in the flying height is independent of meandering and offset. For this reason,
The tension control described in Japanese Patent Application Laid-Open No. 2-204264 is merely for ensuring a non-contact state between the band-shaped material and the floater when passing through a stepped point. It does not control the quantity with high precision. On the other hand, in the helical floater type,
As described above, there is a risk of meandering due to a change in the flying height, in addition to a risk of abrasion due to contact between the belt-shaped material and the floater surface. That is, once a deviation occurs due to a change in the flying height, the deviation causes a meandering that periodically repeats the deviation. This is a hindrance in increasing the line speed because the meandering amplitude increases as the line speed increases. In addition, the occurrence of the offset may cause a trouble in breaking of the band-shaped material 52 in some cases, and may cause a reduction in operation rate. Further, as the floating amount becomes smaller, the gap between the floater and the band-shaped material becomes smaller, the flow velocity of the fluid for floating the band-shaped material becomes faster, and the band-shaped material is apt to flutter, which causes plate breakage and scratches. However, at this time, in the helical floater type, the "twist" is added, so that the plate tends to be inclined in the plate width direction, and the above-mentioned scratches and the like are liable to occur. From this point as well, the helical floater type is required to suppress the fluctuation of the flying height more than the bend floater type. As described above, in the helical floater type sheet passing direction changing device, since the control of the flying height greatly affects the production efficiency, it is required to perform control with much higher precision than in the bend floater type. However, in the conventional helical floater type passing direction changing device, no effective means for controlling the flying height with high accuracy is disclosed. Therefore, as the line speed increases, meandering frequently occurs in a process line employing this apparatus, which is one of the causes of a decrease in production efficiency.
That is, even if a plurality of process lines are continuously connected using a helical floater-type sheet passing direction changing device, a sufficient effect cannot be obtained. The present invention has been made in view of the above-described problems. By controlling the flying height with high precision, it is possible to prevent the occurrence of deviation and meandering of the band-shaped material and to increase the production efficiency. It is an object of the present invention to provide a helical floater type sheet passing direction changing device capable of performing the same. [0017] In order to solve the above-mentioned problems, the present invention relates to a device for changing the direction of passing a belt-like material through which a running belt-like material is wound at a predetermined spiral angle. In a non-contact type plate passing direction changing device that includes a floater that changes the direction of the plate passing and that ejects a fluid supplied from a fluid supply device from the surface of the floater to float and support the band, A floating amount detecting means for detecting a floating amount, and a controller for adjusting a supply flow rate from the fluid supply device based on a deviation between a floating amount of the band-shaped material detected by the floating amount detecting means and a target floating amount. And In the present invention, by directly detecting the floating amount of the band material and controlling the flow rate of the fluid supplied from the fluid supply device so that the floating amount always becomes the target floating amount, the band material is removed. The flow rate of the fluid ejected from the surface of the floater is adjusted for the purpose of supporting, thereby suppressing the fluctuation of the flying height from the target flying height. Here, from the balance of the force, the tension T generated in the strip wound around the floater and the average pressure P for supporting the strip by the fluid have the following relationship (1). is there. (T / W) = (1 / cos ² θ) · R · P (1) where: W: width of the strip R: radius of curvature θ at the position where the strip is wound around the floater: Represents the helix angle. Further, the average pressure P can be approximately expressed by the following equation (2) based on the flying height h of the band-shaped material and the flow rate Q of ejection. P = {Q ² / {2 · (L · h) ² } (2) where, ζ: proportionality constant L: length of the band material wound around the floater. Therefore, from the above equations (1) and (2),
It can be seen that the relationship is as shown in the following equation (3). (T / W) = (K / cos ² θ) · (Q / h) ² (3) K indicates a proportional constant. From equation (3), if the spiral angle is constant, the flying height h is uniquely determined with respect to the linear tension (T / W). Therefore, if the linear tension (T / W) is constant, The same flying height can be obtained irrespective of the width of the strip. When the linear tension (T / W) is kept constant, the flow rate of the fluid supplied from the fluid supply device, that is, the jetting flow rate Q for floating and supporting the strip material, and the floating amount h are as follows. The floating amount h can be changed to an arbitrary value by changing the supply flow rate from the fluid supply device that is proportional to the ejection flow rate Q. Q∝h When the flying height h is constant, the linear tension (T / T
W) and the ejection flow rate Q have the following proportional relationship. (T / W) Ｑ Q ² Therefore, even when the tension of the strip material fluctuates, the floating amount h is kept constant by adjusting the ejection amount Q, that is, the supply flow rate, in accordance with the tension fluctuation. can do. Here, from the above equation (3), the tension fluctuation causes the fluctuation of the flying height h, and the tension fluctuation is proportional to the fluctuation of the flying height. Therefore, the supply flow rate should be adjusted according to the fluctuation of the flying height. Then, the above-mentioned tension fluctuation is absorbed, and the flying height becomes the target flying height. As described above, even if the belt-shaped material fluctuates in tension or the like, by controlling the supply flow rate from the fluid supply device in proportion to the ejection flow rate in accordance with the deviation of the floating amount, the floating amount becomes the target floating amount. It is adjusted to. Next, an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a steel strip will be described as an example of the strip. The basic structure of the threading direction changing apparatus according to the present embodiment is the same as that of the conventional apparatus. As shown in FIG. By being wound around the spiral angle, the steel strip 2
Is changed. The main body of the floater 1 is cylindrical, and its surface has a helical extending position extending along a helical angle of, for example, 45 degrees. ) L has a large number of jet holes 3. Each ejection hole 3 communicates with a flow passage provided inside the floater 1, and the gas is ejected from each ejection hole 3 at a set pressure through the flow passage. The jet holes 3 are arranged on the floater surface at equal pitches. This is, for example,
This is realized by forming the steel strip hooking position portion L with a punching metal or the like. Here, the gas is preferably air from the viewpoint of cost, but may be composed of another gas such as nitrogen, or may be a liquid such as water instead of the gas. Also,
In FIG. 1, the opening shape of each ejection hole 3 is illustrated as a circular hole, but may be rectangular or the like, or the ejection hole 3 may be formed by a slit-shaped opening or the like. Here, in FIG. 1, reference numeral 4 denotes an inflow passage 4 among the above-mentioned flow passages, and reference numeral 5 denotes an outflow passage. A flow meter 6 is provided in the middle of the inflow path 4. A blower 7 constituting a fluid supply device is connected upstream of the inflow path 4. The above flowmeter 6
Can measure the flow rate of the gas flowing through the inflow path 4 and supply the flow rate signal to the controller 8. The blower 7 is capable of pumping gas at a discharge flow rate according to a command from the controller 8. A plurality of flying height detectors 9 are provided at the winding position L of the steel strip 2 on the surface of the floater 1 along the extending direction thereof. In the present embodiment, as shown in FIG. 2, the installation position of the flying height detector 9 is set at the both ends a, in the width direction of the steel strip 2 wound around the floater 1. d, c, f, and both ends b, e in the plate width direction at the center in the longitudinal direction of winding.
Each of the flying height detectors 9 is composed of a laser displacement meter, and as shown in FIG. 3, a detector main body 9a which is disposed on the outer surface of the steel strip 2 so as to face the outside, and a detector main body 9a. And a bracket 9b supported on the surface of the floater 1.
Then, the floating amount of the steel strip 2 at each of the target detection positions a to f is detected, and the detected value can be supplied to the controller 8. Here, in the present embodiment, the flying height detector 9 is constituted by a laser displacement meter, but is not limited to this, and may be an ultrasonic meter or the like. Further, in the above description, the example in which the flying height detector 9 is provided outside the floater 1 is described. However, the present invention is not limited to this, and it may be inside the floater 1 (portion 9c in FIG. 3). Alternatively, the floating amount of the steel strip 2 may be detected from the side. As shown in FIG. 4, the controller 8 mainly includes a flying height calculator 8A, a flying height deviation calculator 8B, a flow deviation calculator 8C, a set supply flow calculator 8D, a PI control calculator 8E, It is composed of a discharge flow controller 8F. The above-mentioned flying height calculator 8A receives the respective flying height signals a to f from the six flying height detectors 9, and obtains the following (4)
Average flying height h obtained by geometrical load averaging by the formula
_AVE is calculated and the average flying height h _AVE is supplied to a flying height deviation calculator 8B. H _AVE = (a + 2b + c + d + 2e + f) / 8 (4) In the flying height deviation calculator 8B, the flying height deviation Δh is obtained by subtracting the target flying height H _REF from the supplied average flying height h _AVE.
Is obtained, and the flying height deviation Δh is supplied to the flow deviation calculator 8C. The flow rate deviation calculator 8C calculates the increase / decrease value of the flow rate corresponding to the flying height deviation Δh based on the following equation (5), and supplies the corrected flow rate ΔQ to the set supply flow rate calculator 8D. ΔQ = f (Δh) (5) The above f (Δh) is set, for example, as K · Δh.
K is a proportionality constant. Here, when obtaining the correction flow rate ΔQ, it is preferable to perform correction in accordance with the pressure loss determined by the opening shape of the ejection hole 3, the set pressure, and the like. The set supply flow rate calculator 8D calculates the supply flow rate to be set by adding the correction flow rate ΔQ to the actual supply flow rate supplied from the flow meter 6, and discharges the supply flow rate via the PI control calculator 8E that converts the flow rate into a PI operation. It is supplied to the flow controller 8F. The discharge flow controller 8F can supply a command to the blower 7 at the supplied set flow rate. As described above, the controller 8 supplies the gas supplied to each of the ejection holes 3 of the floater 1 such that the flying height deviation Δh becomes zero based on the flying height deviation Δh between the current average flying height h _AVE and the target flying height H _REF. Is adjusted. Next, the operation, operation, and the like of the above-mentioned passing direction changing device will be described. The steel strip 2 is successively wound around the floater 1 while being guided by an inlet guide roll (not shown), and is floated and supported by gas so that the direction of the sheet passing is changed in a non-contact state with the floater 1. It is guided by the exit side guide roll and is sent to the next process. At this time, in a steady state where there is no change in the passing state of the steel strip 2, that is, in a state where the average flying height H _AVE of the steel strip 2 with respect to the floater 1 is the target flying height H _REF , Since the deviation Δh is zero, there is no change in the command from the discharge flow rate regulator 8F to the blower 7, so there is no change in the discharge flow rate fed from the blower 7, and the flow rate of the gas blown out from each blowout hole 3. Is kept constant. Accordingly, the supporting pressure of the gas on the steel strip 2 during the passing direction change is kept constant, and the floating amount of the steel strip 2 from the floater 1 is stably maintained at the target floating amount _HREF. As a result, the pass line of the steel strip 2 at the portion wound around the floater 1 is stabilized. That is, the fluctuation of the steel strip 2 in the width direction is suppressed, and the steel strip 2 is stably conveyed with its passing direction changed along the target pass line. If the line speed of the steel strip 2 fluctuates temporarily from the above steady state, the tension of the steel strip 2 wound around the floater 1 fluctuates, and the steel strip 2
The flying height changes. Then, based on the signal from the flying height detector 9, the controller 8 responds to the flying height deviation Δh between the current average flying height h _AVE calculated by the flying height calculator 8A and the target flying height H _REF. The corrected flow rate ΔQ is calculated, and the command value for the blower 7 is changed so that the corrected supply flow rate is obtained. As a result, the floater 1
The flow rate supplied to the inside is changed, and the flow rate of the gas ejected from each ejection hole 3 is adjusted. As a result, fluctuations in the flying height caused by the fluctuations in the tension of the steel strip 2 caused by the above fluctuations are absorbed, the flying height is maintained at the target flying height H _REF, and the steel strip wound around the floater 1 is held. The variation of the pass line length of No. 2 is suppressed, and the pass line is stabilized. That is, as described above, the supply flow rate from the blower 7, that is, the flow rate of the gas ejected from the ejection holes 3 is changed in accordance with the fluctuation from the steady state, so that the supporting pressure of the steel strip 2 by the gas is changed. Is adjusted, and the floating amount of the steel strip 2 from the floater 1 is reliably maintained constant even when the actual tension of the steel strip 2 temporarily changes. Further, not only changes in the flying height due to the fluctuations temporarily generated from the above-mentioned steady state, but also changes in the sheet passing conditions such as a change in the sheet width of the steel strip 2 to be passed, the steel sheet can be reliably removed. The flow rate is automatically adjusted so that the flying height of the strip 2 maintains the target flying height H _REF , the change in the sheet width direction of the steel strip 2 is suppressed, and the pass line is stabilized. As described above, in the passing direction changing device of the present embodiment, even in the case of the non-contact type, by controlling the discharge flow rate from the blower 7, the pass line at the time of changing the passing direction by the floater 1 can be obtained. Is always held at a desired position, and the occurrence of meandering and offset in the width direction of the steel strip 2 on the exit side of the floater 1 can be suppressed. As a result, even if a non-contact type sheet passing direction changing device is applied downstream of the annealing step or the like to make two or more steps continuous, it is possible to operate at a higher line speed than before. Even if the thickness of the steel strip 2 is changed or the operating conditions are changed, the flying height of the steel strip 2 is always the target flying height H _REF.
The pass line of the steel strip 2 in the portion wound around the floater 1 is adjusted to a desired position and stabilized. When changing the flying height, the controller 8
The actual flying height is automatically changed only by changing the target flying height _HREF supplied to the _motor . Here, in the above embodiment, the floater 1
Has a cylindrical shape, but is not limited to this. In the floater 1, only the outline shape of the portion L around which the steel strip 2 is wound has a predetermined substantially circular arc shape. In the above embodiment, the case where the supply flow rate is adjusted by directly changing the discharge flow rate from the blower 7 has been described as an example. The supply flow rate to the ejection holes 3 provided on the surface of the floater 1 may be adjusted by inserting a valve and adjusting the opening of the control valve by the controller 8. In the above embodiment, the feedback control of the flow rate is performed by the signal from the flow meter 6, but it is not always necessary to perform the feedback control. However, the accuracy of the control is improved by performing the feedback control based on the signal from the flow meter 6. An embodiment in which a passing direction changing device which controls the supply flow rate from the blower 7 as described above is actually used.
For comparison, a meandering condition at the outlet side of the floater 1 was confirmed in a case where a passing direction changing device which does not control the flow rate as in the related art was used, and the result shown in FIG. 5 was obtained. Was. In FIG. 5, A is based on the present invention. On the other hand, B is a case where the flow control was not performed as in the related art for comparison. Here, the target flying height H _REF was set to 20 mm, and the steel strip 2 having a thickness of 0.6 mm and a sheet width of 1200 mm was used. As can be seen from FIG. 5, if the flow rate control is not performed, the meandering amount increases as the line speed increases. However, in the apparatus according to the present embodiment, the increase in the meandering amount is suppressed even if the line speed is increased. Have been. That is, it is understood that by controlling the flow rate so that the flying height becomes the target flying height _HREF , the meandering can be suppressed even when the line speed is increased. As described above, in the apparatus for changing the direction of passing a band-shaped material according to the present invention, the supply flow rate is adjusted in accordance with a change in the flying height, thereby temporarily changing the passing state to the passing state. Even if the fluctuation occurs and the flying height fluctuates, the target flying height can always be automatically adjusted. As a result, meandering or the like occurring in the band material during the pass-through conversion is suppressed, and the path line of the band material wound around the floater is maintained at a desired position and stabilized. Further, even if the operating conditions are changed, for example, the band material to be passed is changed, the floating amount of the band material can be reliably and automatically adjusted to the target floating amount. by this,
When changing the passing direction of the strip using the strip passing direction changing apparatus of the present invention, even if the line speed is increased,
At the same time, scratches and the like caused by the contact of the strip with the floater can be avoided, and meandering of the strip is suppressed to a small value, thereby improving production efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram showing an apparatus for changing the direction of passing a band-shaped material according to an embodiment of the present invention. FIGS. 2A and 2B are diagrams illustrating a detection position of a flying height, wherein FIG. 2A is a perspective view thereof, and FIG. FIG. 3 is a cross-sectional view illustrating detection of a flying height. FIG. 4 is a block diagram of a controller. FIG. 5 is a diagram showing a relationship between a line speed and meandering. FIG. 6 is a view showing a conventional floater. FIG. 7 is a diagram showing a conventional belt-shaped sheet passing direction changing device. FIG. 8 is a diagram illustrating a meandering state accompanying a change in a flying height. FIG. 9 is a diagram showing a state of skewing accompanying a change in flying height. [Description of Signs] 1 Floater 2 Steel strip 3 Injection hole 4 Inflow path 6 Flow meter 7 Blower 8A Floating amount calculator 8B Floating amount deviation calculator 8C Flow deviation calculator 8D Flow setting calculator 8E PI control calculator 8F Discharge flow rate Adjuster 9 Flying height detector H _REF Target flying height h _AVE Average flying height Δh Flying height deviation ΔQ Correction flow rate

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yotoshi Yamashita 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Kawasaki Steel Corporation Chiba Works (56) References JP-A-58-135049 (JP, A) Sho 56-127538 (JP, A) JP-A Sho 60-87156 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B65H 23/32 B65H 20/14 B65H 23/032 B65H 23 /twenty four

Claims (1)

(57) [Claim 1] A floater for winding a running strip at a predetermined spiral angle to change the passing direction of the strip is provided, and a fluid supplied from a fluid supply device is provided. In the non-contact type sheet passing direction changing device for ejecting the float from the floater surface to float and support the strip, the float detecting means for detecting the float of the strip from the floater surface, and the band detected by the float detecting means A controller for adjusting a supply flow rate from the fluid supply device based on a deviation between a floating amount of the material and a target floating amount.