JPH11278643A - Carrying object position tracking method and its device, moving speed detection method and its device, and position control method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform accurate position tracking in spite of small scale remodeling by tracking the position of a carried object using only the rotation speed of the carried object carrying rollers on which the carried object is placed in order. SOLUTION: The calculation to detect the position of a steel material 8 is started when it is recognized that the steel material 8 is positioned at a reference position by the head and tail detection signals output from the inlet side hot metal detector of a certain speed control section, and the movement from the place is performed by integrating the pulses sent from the first roller rotation detector PL1, and then multiplying the result by the moving distance per one pulse. In the tracking using this roller rotation detector PL1, it is required for accurate tracking to switch the first roller rotation detector PL1 to a roller rotation detector PL2 when the steel material 9 passes through the first roller rotation detector PL1 and moves to the next roller rotation detector PL2. This switching operation is performed by detecting that the steel material 8 has moved to the carrying roller R3, on which the roller rotation detector PL2 is provided, from the load torque current of the motor M3 of the carrying roller R3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for tracking the position of a conveyed object, a method and a device for detecting a moving speed, and a method and a device for position control. (Including speed) is continuously and accurately tracked, and based on the tracking information and the speed information, processing equipment for carrying out a process that requires a process control, for example, a steel material such as a steel plate, an H-shaped steel, and a sheet bar. Suitable for use in a hot rolling line or the like, it is possible to accurately track the position of an object conveyed using a plurality of rolls individually driven by a motor, a position tracking method and apparatus for a conveyed object, A method and an apparatus for detecting a moving speed of a conveyed object using the position tracking method, and
The present invention relates to a method and an apparatus for controlling the position of a conveyed object using the position tracking method and apparatus.

[0002]

2. Description of the Related Art In a conventional roll-based transport facility,
The position detection of the conveyed object is performed by integrating the number of rotation pulses (or the average value thereof) obtained from a very small number of rolls, such as one or two representative rolls of each speed control section, from the reference position, and displaying the results on the rolls. This is to calculate the moving distance of the transported object on board.

[0003]

However, in a usual transport roll facility, even a speed control section having a plurality of motors has only one motor drive power supply device such as a thyristor leonard, and each motor has its own motor drive unit. There is no individual speed control. Therefore, due to the difference in the load depending on the presence or absence of the conveyed object on the roll, each roll speed is greatly different from several% to several tens% due to the hanging characteristics of the motor.

[0004] For this reason, there has been a problem that the output pulse of the rotation detector of the representative roll cannot always constantly and accurately give the tracking information of the transported object.

As a method of reducing such an error, a sensor for detecting a transport object such as an optical type is installed at a main point of the transport line, and the rotation detector output is detected based on the detection information of the transport object at the installation point. Although the method of calibrating the position information is also adopted, an error still occurs between the installation points of the sensors, and it was not possible to continuously maintain sufficient accuracy.

On the other hand, in order to improve the speed control accuracy, there is a case where the speed feedback control of the power supply of the speed control section is performed using a typical roll speed.
Accuracy improves when the transported object is on the representative roll, but when the transported object moves to another roll,
You will have the same problem.

[0007] As a method for solving this problem, each roll motor is provided with a transport facility having a speed feedback control function, or a roll drive shaft in a speed control section is connected by a gear or the like, and each roll is driven by a machine. There is a method of controlling the speed of one motor that rotates a common shaft so that the speed becomes uniform, and detecting the rotation. However, in large facilities, both are very mechanically and electrically. Expensive equipment is required, and in particular, remodeling of existing equipment has a problem that it is not economically practical.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and enables accurate position tracking with a small-scale modification in a configuration of a relatively inexpensive general roll-based transport facility. As a first subject.

A second object of the present invention is to enable accurate detection of the moving speed in the same manner.

Another object of the present invention is to enable accurate position control in the same manner.

[0011]

SUMMARY OF THE INVENTION The present invention is directed to a method for tracking the position of an object to be conveyed using a plurality of rolls individually driven by a motor, by rotating the rolls at intervals shorter than the minimum length of the object to be conveyed. The first problem is solved by detecting the number and sequentially using only the rotation speed of the transport object loading roll on which the transport object is actually mounted to track the position of the transport object.

Further, the transported object loading roll is detected by a load torque current of a motor for driving each roll, so that the transported object loading roll can be easily and reliably detected.

Further, the position of the transport object loading roll detected by the load torque current is backed up by the transport object loading position information obtained from the length of the transport object, so that the position of the transport object loading roll by the load torque current is controlled. Even if detection is not possible, accurate tracking can be performed.

Further, when there are a plurality of rolls on which the transported object is loaded, an average value or a minimum value of the number of rotations of each roll is used, so that the number of rotations can be detected with high accuracy.

Further, the position information obtained from the rotation speed of the transporting object loading roll is calibrated by the output of a sensor for detecting the transported object, thereby improving the accuracy of the position tracking.

The present invention also provides a position tracking apparatus for tracking a position of an object to be conveyed using a plurality of rolls individually driven by a motor, wherein the position of the object is smaller than the minimum length of the object. A roll rotation detector disposed on a roll, and a drive current detection unit for detecting a load torque current of a motor driving each roll,
A roll driven by a motor whose load torque current is larger than a predetermined value is a load roll determining means for determining a transport object loading roll on which a transport object is actually mounted, and is determined as the transport object loading roll. The first problem is solved by providing tracking calculation means for tracking the position of the conveyed object by sequentially using only the outputs of the roll rotation detectors disposed on the rolls.

The present invention solves the second problem by obtaining the moving speed of the transported object from the position information of the transported object detected by using the tracking method as described above. .

According to the present invention, there is also provided a method for detecting a position of a conveyed object using the position tracking apparatus as described above.
The second problem is also solved by providing a moving speed calculating means for calculating the moving speed of the transported object.

According to the present invention, the position of the conveyed object is controlled based on the position information of the conveyed object detected by using the position tracking method as described above.
It is a solution to the above problem.

The present invention also includes a position control means for controlling the position of the conveyed object based on the position information of the conveyed object detected using the position tracking device as described above. It is a solution to the above problem.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention applied to an H-section steel hot rolling line will be described below in detail with reference to the drawings.

In the present embodiment, as shown in FIG. 1, the motor drive power supply units 10 ', 10... Each drive motor (also called a roll motor or table motor) M4 for each speed control section S', S. 'To M7', M1 to M7
A large number (seven for each speed control section) of the transport rollers R4 'to R7', R1 to R7.
.. in a hot rolling line for transporting the steel material 8 by using a transport roller R having an interval shorter than the minimum length L of the steel material 8
2 ', R4', R6 ', R1, R3, R5, R7 ...
Roll detectors (PLG) PL2 ', P
L3 ', PL1, PL2, PL3, PL4..., And load torque currents i'4 to i' of the motor driving the rolls
7, current detector I 'for detecting i1 to i7...
4 to I′7, I1 to I7..., And the passage of the leading end of the steel material 8 near the boundary between the main points of the line, for example, the speed control sections S ′, S. Detection signal hm
Output a 1, hm2, a hot metal detector (HMD) HM1, HM2,... For tracking reference detection;
The load torque currents i4 'to i7', i1 to i7 ...
The transfer roller driven by the motor whose value is larger than a predetermined value is determined by a load roll determining unit that determines the transfer object loading roll on which the steel material 8 is actually mounted, and the transfer roller determined to be the transfer object load roll. Tracking operation means for tracking the position of the steel material 8 by sequentially using only the output of the roll rotation detector provided, and movement for obtaining the movement speed Vfb of the steel material from the position information Dfb of the steel material detected by the tracking operation means. A steel tracking calculation device 30 including, for example, a microcomputer including a speed calculation means and the like is provided.

The roll rotation detectors PL2 'to PL2
3 ', the arrangement interval of PL1 to PL4 is set to an interval shorter than the minimum length L of the steel material 8, and is preferably not more than half of the minimum length L if possible. In this embodiment, a roll rotation detector is provided for every other transport roller R4 ', R6', R1, R3, R5, R7,.

The hot metal detectors HM1, HM2
.. Detect the leading end of the steel material 8 based on the presence or absence of a heat ray detected from the steel material 8 in a red hot state. In addition, steel material 8
Is not limited to the HMD, and an optical tail end sensor such as a photoelectric switch having a light emitter and a light receiver can be used.

The steel tracking arithmetic unit 30 includes:
In addition to this section, the previous section, the rear section, etc.
Data from other sections have been entered as well.

In the position detection calculation of the steel material 8, first, it is recognized that the steel material 8 exists at the reference position by the leading and trailing end detection signal hm1 of the output of the hot metal detector HM1 on the input side of a certain speed control section (here, S). The movement from there is started by integrating the pulse pl1 from the first roll rotation detector PL1, as shown in FIG.
Moving distance k per pulse k (= m / P: where m is PL
The arrangement interval of G and P are multiplied by the total number of pulses of the arrangement interval.

In the tracking using this PL1, when the steel material 8 passes through the PL1 and shifts to the next PL2,
Switching to using PL2 is necessary for accurate tracking. So, for this switch,
The fact that the steel material 8 has moved to the transport roll R3 provided with PL2 is detected from the load torque current i3 of the motor M3 of the transport roller R3.

Further, in the case of a lightly loaded material, in addition to the tracking information calculated and recognized as the switching logic, a method of determining from a steel material loading position obtained from steel material length information given in advance is used as a backup. You can also.

The logic for detecting the roll on which the steel material rides is as follows. That is, the motor load torque T (k
gm) is represented by the following equation.

T = To + Taco + TL + TacM (1)

Here, To is a steady torque when there is no steel material, Taco is an acceleration torque when there is no steel material, and TL is
Steady torque due to steel load, TacM is the acceleration torque required to accelerate the steel, and when the acceleration rate is constant, To and Taco are constant.

Further, the steady torque TL due to the load of the steel material is expressed by the following equation.

TL = KμWg (2)

Here, W is the weight (kg) of steel material per roll, μ is the friction coefficient of the shaft system, K is the conversion coefficient of the motor shaft system, and TL is a function of the steel material weight W.

The torque TacM for accelerating the steel material is
It is expressed by the following equation.

[0036] ^{TacM = (GD 2/375)} · dN / dt ... (3)

Here, GD ² is the motor shaft converted inertia of the material, and N is the motor rotation speed (rpm).

The motor shaft converted inertia GD ² is represented by the following equation.

GD ² = (W / 9.87) · (V / N) ² (4)

Here, V is a steel material speed (mpm).

Therefore, as shown in FIG.
The presence or absence of a steel material can be detected by determining whether the torque is near To or near To + TL based on the motor current i.

During acceleration, the presence or absence of a steel material can be detected by determining whether the torque is near To + Taco or near To + Taco + TL + TacM.

If only the rotation detector data provided on the steel material loading roll detected in this way is used sequentially for the position calculation as shown in the lower part of FIG. 2, the actual steel material transfer position can be calculated. It is possible to calculate correctly.

When the steel material is on two or more transport rollers at the same time and there are a plurality of steel material loading rolls, the average value or the minimum value of the number of rotations of each roll can be used. Here, the reason why the minimum value is used is that there is a possibility that a slip occurs when the roller rotation speed is higher.

When the steel weight information W is obtained in order to improve the accuracy of the determination of the load of the presence or absence of the steel material, this information can be used together.

Further, when the steel material length is given, even if the motor load information cannot be taken in by the material tracking information calculated by itself, a backup for switching the rotation detector used for the distance calculation can be performed.

Further, the signal of the rotation detector selected according to the present invention indicates that the speed of the steel material itself is detected more accurately than usual, and this material speed signal Vfb is, for example, shown by a broken line in FIG. As shown in FIG. 7, the processing quality can be improved by feeding back to the motor drive power supply device 10 to perform speed correction control of the motor drive current or to use it as other process control data or material processing information.

In the above-described embodiment, the present invention is applied to the hot rolling line of the H-section steel, but the present invention is not limited to this. It is clear that the present invention can be similarly applied to the material transfer equipment.

[0049]

According to the present invention, it becomes possible to continuously and accurately track the leading and trailing ends of a conveyed object and accurately detect a moving speed. For example, in an automatic rolling line,
At the optimal timing, it is possible to perform process control such as opening and closing of the guide, cooling water flow control, acceleration / deceleration, and forward / reverse rotation. Therefore, the quality can be improved, and the efficiency can be improved by shortening the time cycle and the rolling pitch.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main configuration of a hot-rolled steel rolling line to which an embodiment of the present invention is applied.

FIG. 2 is a diagram showing a steel material position, each motor load, and a roll rotation detector output switching state in the embodiment.

FIG. 3 is a diagram showing transition of a motor load, a speed, and a material presence / absence state.

[Explanation of symbols]

 8 steel material 10 motor drive power supply device M1 to M7 motor R1 to R7 transport rollers PL1 to PL4 roll rotation detector I1 to I7 current detector HM1, HM2 hot metal detector (HMD) hm1, hm2 Tail edge detection signal

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B21B 39/00 G01B 21/00 C B21C 51/00 B21B 37/00 BBH G01B 21/00 136B

Claims (10)

[Claims] When tracking the position of a conveyed object using a plurality of rolls individually driven by a motor, the number of rotations of the roll is detected at intervals shorter than the minimum length of the conveyed object, and the actual conveyance is performed. A position tracking method for a transported object, characterized in that the position of the transported object is tracked by sequentially using only the rotation speed of the transported object loading roll on which the object is riding. 2. A method according to claim 1, wherein said transport object loading roll is detected by a load torque current of a motor for driving each roll. . 3. The method according to claim 2, wherein the position of the transport object loading roll detected by the load torque current is backed up by transport object loading position information obtained from the length of the transport object. A method for tracking the position of a conveyed object, characterized in that: 4. The method according to claim 1, wherein when there are a plurality of rolls on which the transported object is loaded, an average value or a minimum value of the number of rotations of each roll is used. Object position tracking method. 5. The position tracking method for a transported object according to claim 1, wherein the position information obtained from the rotation speed of the transported object loading roll is obtained by an output of a sensor for detecting the transported object. A position tracking method for a transported object, characterized by performing calibration. 6. A position tracking device for a transported object for tracking the position of an object transported by using a plurality of rolls individually driven by a motor, wherein the device is disposed on rolls having an interval shorter than the minimum length of the transported object. Roll rotation detector, and drive current detection means for detecting the load torque current of the motor driving each roll, the roll driven by the motor the load torque current is greater than a predetermined value, A loading roll determining means for determining a transported object loaded roll on which a transported object is actually mounted; and a transported object using only the output of a roll rotation detector disposed on the roll determined to be the transported object loaded roll. And a tracking calculating means for tracking the position of the object. 7. The transporting method according to claim 1, wherein a moving speed of the transported object is obtained from position information of the transported object detected by using the position tracking method of the transported object according to any one of claims 1 to 5. A method for detecting the moving speed of an object. 8. The position information of a transport object detected by using the position tracking device for a transport object according to claim 6:
A moving speed detecting device for a transported object, comprising a moving speed calculating means for calculating a moving speed of the transported object. 9. A method for controlling the position of a transported object based on position information of the transported object detected by using the method for tracking the position of a transported object according to claim 1. To control the position of the conveyed object. 10. A position control means for controlling the position of a conveyed object based on position information of the conveyed object detected by using the conveyed object position tracking apparatus according to claim 6. Position control device for transported objects.