JP2941595B2 - Bridle Roll Clutch Control Method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a rolling apparatus and a processing line for various metal strips such as steel strips, galvanized steel strips, stainless steel strips, aluminum steel strips and the like. The present invention relates to a bridle clutch control for use in which the magnitude relationship between the entrance side and the exit side tension of a bridle device for giving is reversed.

[0002]

2. Description of the Related Art Bridle rolls are incorporated into a line of a metal strip, and are installed at the entrance and the exit of a pass line in order to continuously apply tension to a metal strip passing therethrough. A skin pass mill and a tension leveler device are laid out between the entrance and exit bridle rolls. In addition, an intermediate bridle roll is installed between the entrance and exit bridles in case the distance between the entrance and exit bridle rolls is long or the tension is reduced by a device such as a tension leveler. You.

[0003] When passing through a bridle roll, there has conventionally been a problem of occurrence of surface flaws due to relative sliding between the roll surface and the metal strip. On the other hand, as described in JP-B-46-6854 and JP-B-46-8577, slippage is prevented by a method such as changing the outer diameter of a roll in a combination of bridle rolls. We try to suppress the generation of flaws.

[0004]

However, for example, when a skin pass mill is arranged upstream of the intermediate bridle roll and a tension leveler is arranged downstream,
The tension relationship between the entrance side and the exit side of the intermediate bridle roll changes depending on the passing condition of the metal strip. That is, rolling only with a skin pass mill Rolling only with a tension leveler (straightening) Rolling simultaneously with a skin pass mill and a tension leveler There are four conditions for both the skin pass mill and the tension leveler, ie, an empty pass. , The tension relationship between the outlet sides changes.

[0005] Under the condition, the entrance tension Te of the intermediate bridle becomes larger than the exit tension Td (Te> T).
d) In the case of the condition, on the contrary, the output side tension Td becomes larger than the input side tension Te (Te <Td). Further, in the case of the conditions, the relationship of the tension changes depending on the rolling conditions of the material to be rolled, the skin pass mill and the tension leveler (there are also Te> Td and Te <Td). In general, Te = Td under the condition.

In such an intermediate bridle in which the longitudinal tension relationship of the bridle roll changes depending on the passing condition, the slip cannot be prevented only by the technique described in the above-mentioned publication. In other words, if only the condition that the tension on the output side is increased, increasing the outer diameter of the roll toward the output side is effective against slippage, but the tension increases depending on the threading condition. If the direction changes to the entry side, slippage is likely to occur. Therefore, there remains a problem that surface defects of the metal strip occur. In order to solve this, the bridle roll diameter is arranged so that it is larger, smaller, larger or smaller, larger, or smaller than the inlet side (upstream side). In addition, a roll to be used may be selected by a clutch installed on each roll so that a small-diameter roll is arranged on the low tension side.

However, there is no means for detecting the tension relationship between the entrance side and the exit side of the bridle with high reliability, and there has been no example in which such a bridle has been adopted so far.

An object of the present invention is to provide a method for continuously and reliably detecting the longitudinal tension relationship of a bridle in such a bridle apparatus, and to solve the above-mentioned problem.

[0009]

According to the present invention, the bridle roll diameter is arranged as a large diameter, a small diameter, and a large diameter, or is arranged as a small diameter, a large diameter, and a small diameter, and the longitudinal tension relationship of the bridle drives the bridle. Utilizing a relationship proportional to the power of the apparatus, the direction of torque acting on the bridle is determined from the electric power of the motor, and clutch switching is performed so that a large-diameter roll is always arranged on the high tension side of the metal strip.

[0010]

The power for driving the bridle is proportional to the product of the tension difference before and after the bridle and the number of rotations of the bridle roll.
It is expressed by the following equation (1).

P∞ (Te−Td) × N (1) where, P: bridle drive power Te: bridle entry side tension Td: bridle exit side tension N: bridle rotation speed Therefore, the power P of the drive device From the polarity (+,-) of the value, the longitudinal tension relationship of the bridle is found. That is, the P value is +
, Te> Td, and if the P value is −, Te <T.
d. Because this method is sensorless,
It can be said that it is a low-cost and highly reliable method.

[0012]

1 is a schematic diagram of a line with clutch control of the bridle of the present invention. In the figure, a metal strip S
An intermediate bridle 1 is incorporated in the line, and a skin path mill 2 is disposed upstream of the intermediate bridle 1 and a tension leveler 3 is disposed downstream thereof. An entrance bridle 4 is disposed upstream of the line, and an exit bridle 5 is disposed downstream of the line, whereby tension is applied to the metal strip S passing through the skin pass mill 2 and the tension leveler 3.

The intermediate bridle 1 is a roll 1 of No. 1, No. 2 and No. 3 from upstream to downstream of the pass line.
This is a three-roll type in which a, 1b and 1c are arranged. The outer diameters of these rolls are provided with an appropriate difference according to the change in tension.

6 is a main drive motor, 7 is an entrance bridle 4
, A motor for controlling the elongation of the metal strip S on the outgoing side bridle 5,
Motor for controlling the elongation of the outgoing side to control the elongation of the outside, 9 is an incoming differential planetary gear, 10 is an outgoing differential planetary gear, 11 is an incoming bevel gear, 12 is an intermediate bevel gear, and 13 is an outgoing bevel gear. , 14 is an input side distribution gear, 15 is an intermediate distribution gear, 16
Is a delivery gear, and 17 is a clutch (torque transmitting device) of the No. 1 roll 1a and the No. 3 roll 1c of the intermediate bridle 1.

The arrow in the figure indicates the direction of the flow of electric power, and when it is determined as follows, the following equation (2) is established.

P _ME : electric power recovered from the entrance bridle 4 to the main drive motor 6, the direction of recovery being + P _SE : electric motor 7 from the entrance bridle 4 to the entrance elongation ratio
To the power to be recovered, the direction to be recovered + P _MD: in power delivered to the exit side bridle 5 from the main drive motor 6, the direction sent + P _SD: from egress elongation control electric motor 8 Outgoing bridle 5
The power delivered to the direction of sending _{+ Pc = Po + P ME -P} MD ··· (2) where, Po is the generated power of the main drive motor 6,
Pc is electric power transmitted from the main drive motor 6 to the intermediate bridle 1. If the Pc value is +, it indicates that power is being sent from the main drive motor 6 to the intermediate bridle 1, which indicates that Te> Td in the intermediate bridle inlet / outlet tension relationship. Further, the Pc value is-
, The power is supplied from the intermediate bridle 1 to the main drive motor 6
This indicates that Te <Td in the intermediate bridle inlet / outlet tension relationship.

Therefore, by controlling the clutch based on the polarity determination of the Pc value, it is possible to prevent relative slippage between the roll surface and the metal strip. For example, in the case of a three-roll bridle, when the No. 1 roll 1a has a small diameter, the No. 2 roll 1b has a large diameter, and the No. 3 roll 1c has a small diameter from upstream to downstream of the bridle, clutch control is performed. The method is as shown in Table 1 (in the case of a three-roll bridle, no clutch is provided based on the center No. 2 roll 1b).

[0018]

[Table 1]

The strong excitation in Table 1 means the excitation current of the clutch corresponding to the torque required to secure a predetermined tension, and the weak excitation corresponds to the torque required to accelerate and decelerate the roll itself. It means the exciting current of the clutch. Further, "OFF" means that torque is not transmitted to the roll when the clutch is released.

The values of P _ME and P _MD in the above equation (2) are
Motor power P _SE for controlling the elongation at the entry side via the differential planetary gear
And can be replaced by the output side elongation rate control motor power P _SD . Therefore, when the equation (2) is expressed by using the values of P _SE and P _SD , the following equation (3) is obtained.

[0021]

(Equation 3)

Here, Po: main drive motor power (measured value) P _SE : input side elongation rate control motor power (measured value) P _SD : output side elongation rate control motor power (measured value) A to F: Coefficient determined by the number of teeth, pitch circle radius, and roll diameter of the differential planetary gear εE: Elongation at entry skin pass mill (set value or measured value) εD: Elongation at output tension leveler (set value or Measured value) η _ME : Efficiency of drive system on the inbound side η _MD : Efficiency of drive system on the outgoing side That is, each power value of the main drive motor and the motor for controlling the elongation and elongation of the bridle device, and the skin pass mill and leveler The tension relationship before and after the intermediate bridle can be determined by the elongation of the part.

FIG. 2 conceptually shows the control method of the present invention. In the figure, reference numeral 18 denotes a main drive motor control device, 19 denotes a motor control device for controlling the inward elongation ratio, and 20 denotes a motor control device for controlling the elongation elongation ratio. Active power is output from a number or from the voltage and current of the motor. 21 is
An arithmetic unit that averages the power signal of the electric motor and calculates the Pc value using the elongation signal. Reference numeral 22 denotes a comparator for determining the polarity of the Pc value, which also has a dead zone function for preventing clutch chattering. Reference numeral 23 denotes a clutch control device, which controls the clutch current.

[0024]

According to the bridle apparatus having at least three roll rows, the roll diameter is larger than that of the upstream side.
The following effects can be obtained by using the bridle arranged as small, large or small, large, small together with the control of the present invention. (1) In any case of various passing forms, the relative slip between the roll surface and the metal strip surface can be suppressed completely or to the extent that it does not cause actual harm, so high quality processing is possible. is there. (2) Since the relative slip between the roll surface and the metal strip surface is eliminated or reduced, the life of the roll is extended. (3) In any case of various threading forms, relative slip between the roll surface and the metal strip surface can be suppressed completely or to the extent that it does not cause actual harm, so it is considered to be caused by stick slip. An excellent elongation action without tension fluctuation can be performed without vibration of the strip. (4) It is easy to adjust the set tension when the thickness changes.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a facility configuration of a strip plate transport line that embodies the present invention in one embodiment.

FIG. 2 is a block diagram conceptually showing the control contents of the present invention by functional blocks.

[Explanation of symbols]

1: Intermediate bridle (1a: No. 1 roll, 1b: No. 2 roll, 1c: No. 3 roll) 2: Skin pass mill
3: Tension leveler 4: Inlet bridle 5: Outlet bridle 6: Main drive motor 7: Inlet elongation rate control motor 8: Inlet elongation rate control motor 9: Inlet differential planetary gear 10: Outlet differential Moving planetary gear 11: Incoming bevel gear 12: Intermediate bevel gear 13: Outgoing bevel gear 14: Incoming distribution gear 15: Intermediate distribution gear 16: Outgoing distribution gear 17: Clutch (torque transmission device) 18: Main drive motor control device 19 ： Control device of the motor for controlling the elongation at the entrance side 20 ： Control device of the motor for controlling the elongation at the exit side 21 ： Pc calculator 22 ： Comparator (comparator) 23 ： Clutch control device S ： Metal strip Po ： Main drive motor Electric power (measured value) P _ME : Electric power collected from entrance bridle 4 to main drive motor 6 P _SE : Electric motor for entrance elongation control 7 from entrance bridle 4
(Electric power for control of elongation rate control: measured value) P _MD : Power transmitted from main drive motor 6 to output bridle 5 P _SE : Power output from elongation rate control motor 8 to output bridle 5
(Electric power for output elongation control: measured value) Pc: Electric power transmitted from the main drive motor 6 to the intermediate bridle 1 Te: Bridle entrance tension Td: Bridle exit tension εE: Ingress skin pass Elongation at mill εD: Elongation at output tension leveler

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshimi Tsuruyama 46-59 Ohara Nakahara, Tobata-ku, Kitakyushu Nippon Steel Corporation Machinery & Plant Division (58) Fields surveyed (Int. Cl. ⁶ , DB Name) B21B 39/08 B21B 39/34 B21C 47/00

Claims (1)

(57) [Claims] 1. A bridle device comprising a distribution gear having one drive shaft and at least three or more output shafts, a clutch for transmitting torque, and a roll for transmitting the torque to a metal strip. , The bridle roll diameter is changed from upstream to downstream of the flow of the metal plate, large diameter, small diameter,
Place it with a large diameter or place it with a small diameter, a large diameter, a small diameter,
A clutch control method for a bridle roll, which determines the direction of torque acting on the bridle from the electric power of the motor driving the bridle and switches the clutch so that the large-diameter roll is always arranged on the high tension side of the metal strip.