JP2000007132A - Material carrier device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To contrive a location stop with high accuracy by correcting a location actual record of a material moved by defining a set location of a second sensor as a reference by using a ratio of an actually measured distance between first and second sensors provided at an upstream end of a roller table which is upstream of a roller table at a stop target location of the material and an arithmetic distance between the first and second sensors calculated by speed actual record of a roller table which is downstream of the table of the stop target location of the material. SOLUTION: After a tip of a material 1 is detected by a material sensor 9, a calculation of a material moving distance is started. A speed control of a roller table 2 is performed so as to stop the material at a point of time when a distance which is substantially shorter than the calculated and obtained material location actual record is coincided with an actually measured distance from an installation location of the material sensor 9 up to a stop target location. A location actual record correction circuit 12 adds the material location actual record that a calculation of the material location actual record obtained by counting a pulse in a pulse count circuit 11 is executed and corrected to a subtracting machine 13. Therefore, a fixed location stop with high accuracy is made possible, regardless of the shape of the material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a material conveying device installed in a hot rolling line.

[0002]

2. Description of the Related Art FIG. 2 is a schematic structural view of a conventional material conveying device installed in a hot rolling line. In the figure, a plurality of roller tables 2 are arranged in series in the direction of transport of the material 1 indicated by arrow A. Generally, four or more roller tables 2 are often arranged, but FIG. 2 shows a case where three roller tables 2 are arranged for simplification of the drawing. The roller table 2 includes a predetermined number of rolls, and an electric motor 3 is coupled to each of these rolls. Further, a drive device 4, a drive device 5, and a drive device 6 for supplying drive power to the electric motor 3 are provided for each roller table 2, and these drive devices are provided in the corresponding roller table 2 according to the same speed reference _Vref. The speed of the electric motor 3 is controlled.

[0003] Of the above-mentioned roller tables 2, a roller table in which a target stop position of a material is set, that is,
A speed detector 7 for detecting the speed is attached to one of the rolls of the roller table that is speed-controlled by the drive device 5, in the illustrated example, the roll located on the most upstream side. The speed detector 7 outputs a voltage signal having a magnitude corresponding to the rotation speed and applies it to the material position control circuit 10A.
A material sensor 9 is provided between the roller table 2 driven by the drive device 4 and the roller table 2 driven by the drive device 5.

The material position control circuit 10A includes a pulse count circuit 11, a subtractor 13, and a speed reference circuit 14 as position result detecting means. Among them, the pulse count circuit 11 converts the voltage signal detected by the speed detector 7 into a pulse signal having a frequency corresponding to the magnitude thereof, counts the pulses, and starts from the material sensor 9 of the conveyed material. The actual position D _count to be performed is detected. Subtractor 1
3 is a position reference D _ref as a target position for stopping the material.
And calculating a difference between the actual position D _count a speed reference circuit 1
Add to 4. The speed reference circuit 14 converts the difference between the position reference D _ref and the actual position D _count into a speed reference V _ref and adds the difference to the drive devices 4 to 6.

[0005] When a target stop position P of the material is set in the middle of the roller table 2 driven by the drive device 5 in the transport direction, the distance from the installation position of the material sensor 9 to the target stop position P of the material is reduced. It is added to the subtractor 13 as the position reference _Dref . The pulse count circuit 11 starts the actual position D from the time when the material sensor 9 detects the leading end of the material 1.
Output _count . When the position reference D _ref matches the actual position D _count , the speed reference V _ref output from the speed reference circuit 14 becomes zero, and the driving of the roller table 2 is stopped.

[0006]

The bottom surface of the material 1, that is, the surface on which the material is placed on the roller table 2, is generally flat in many cases. In this case, since a substantially uniform load is applied to the roll on which the material 1 is placed, the loads on the plurality of electric motors 3 are also substantially constant. However, when the material 1 is curved in the vertical direction, the load of the material 1 is applied only to a small number of rolls among a plurality of rolls driven by one drive device. When the mounting surface of the material 1 on the roll is concavely curved with respect to the horizontal plane, in an extreme case, only the leading end and the rear end viewed in the traveling direction of the material 1 are in a state of being on the roll. In addition, the load of the material is intensively applied to the two rolls.

As is well known, when an induction motor is used as the electric motor 3, the slip varies depending on the load applied to the induction motor. There is a difference between the rotation speed of the rolls that are present and the rotation speed of the rolls that are not loaded with material. Therefore, when no load is applied to the roll to which the speed detector 7 is attached, the difference between the actual speed detected by the pulse count circuit 11 based on the speed signal of the speed detector 7 and the actual speed is obtained. As a result, there is a case where the material cannot be stopped at a fixed position with respect to the target stop position P.

In addition, when the load of the induction motor is increased due to the concentrated load, the slip increases, and the actual material speed may not reach the target speed reference.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a first object of the present invention is to provide a material transporting apparatus capable of performing high-precision fixed-position stop control irrespective of the material shape. is there.

A second object of the present invention is to provide a material conveying apparatus capable of matching a material speed to a speed reference.

[0011]

The invention according to claim 1 is
A plurality of roller tables are arranged in series in the material transport direction, and the same speed reference is given to a drive device provided for each roller table, and the material is located at the stop target position on the second and subsequent roller tables in the material transport direction. A first material sensor provided at an upstream end of a roller table upstream of a roller table at which a target stop position of a material is set, and a second material sensor provided at a downstream end of the roller table.
A material sensor, a speed detecting means for detecting the actual speed of the roller table downstream of the roller table on which the target stop position of the material is set, and a speed actual value of the roller table detected by the speed detecting means. Position record detecting means for detecting the position record of the material moved with reference to the installation position of the second material sensor, and the actual measured distance between the first and second material sensors and the roller table speed record detected by the speed detecting means. Position correction means for correcting the position result of the material position detection means using the ratio of the calculated distance between the first and second material sensors calculated based on is there.

According to a second aspect of the present invention, in the material transporting apparatus according to the first aspect, time detecting means for detecting a time when the material passes between the first and second material sensors; The actual speed of the material is calculated based on the measured distance between the material sensors and the material passage time detected by the time detecting means, and the obtained actual speed of the material and the actual speed of the roller table detected by the speed detecting means are calculated. And speed reference correction means for correcting the speed reference using the ratio of

According to a third aspect of the present invention, in the material transport apparatus according to the second aspect, a predetermined upper limit is set to a ratio between the calculated actual speed of the material and the actual speed of the roller table detected by the speed detecting means. It is characterized by having been provided.

According to a fourth aspect of the present invention, in the material transport apparatus of the second aspect, the ratio between the calculated actual speed of the material and the actual speed of the roller table detected by the speed detecting means is a predetermined upper limit value. , A means for displaying a warning when the state has reached is provided.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on preferred embodiments shown in the drawings. FIG. 1 is a schematic configuration diagram of an embodiment of a material conveying apparatus according to the present invention. In the figure, the same elements as those in FIG. 2 showing a conventional apparatus are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the target stop position P of the material is set on the roller table driven by the drive device 5, and the roller table upstream of the roller table, that is, the roller table driven by the drive device 4, The material sensor 8 is newly installed at the upstream end, and the material sensor is provided at the upper and lower ends of the roller table driven by the drive device 4 together with the material sensor 9 described above. Further, the speed detector 7 is attached to a roller table downstream of the roller table in which the target stop position P of the material is set, that is, a roller table driven by the drive device 6 and having no material 1 mounted thereon. A signal is applied to the material position control circuit 10B.

In the material position control circuit 10B, a position result correction circuit 12, a timer circuit 15, and a speed reference correction circuit 16 are newly added to the elements constituting the material position control circuit 10A shown in FIG. I have. Among them, the position performance correction circuit 12 uses the ratio of the measured distance between the material sensors 8 and 9 and the calculated distance calculated based on the speed signal of the speed detector 7 to calculate the material counted by the pulse count circuit 11. The position result is corrected and added to the subtractor 13. The timer circuit 15 as time detecting means detects the time when the material 1 passes between the material sensor 8 and the material sensor 9. The speed reference correction circuit 16 includes the first and second
The actual speed of the material is calculated based on the actually measured distance between the material sensors and the material passage time detected by the timer circuit 15, and the obtained actual speed of the material and the speed of the roller table detected by the speed detector 7 are calculated. The speed reference output from the subtractor 13 is corrected using the ratio with the actual result.

The operation of the present embodiment configured as described above will be described below. It is assumed that the material is conveyed by giving the speed reference _Vref having a fixed value to the drive devices 4 to 6. At this time, the pulse _count value based on the output signal of the speed detector 7 from when the tip of the material 1 is detected by the material sensor 8 to when it is detected by the material sensor 9 is P _count (inc).
And then, the material movement amount per one pulse, i.e., when the weight and _{W coun t (mm / inc)} , the distance D from the tip of the material 1 is detected by the material sensor 8 until detected by the material sensor 9 _count is calculated by the following equation.

D _count = P _count × W _count (mm) (1) On the other hand, if the measured distance from the material sensor 8 to the material sensor 9 is D _meas1 (mm), D _count does not match D _meas1. , D _count > D _meas1 . The reason for this is
Since no material is placed on the roller table 2 to which the speed detector 7 is attached, the roller table 2 rotates at substantially the same speed as the speed reference given to the drive device 6, whereas the roller table driven by the drive device 4 rotates. This is because the material 2 is loaded on the material 2 and is slower than the speed reference, and as a result, the transport speed of the material 1 is lower than the speed reference given to the drive device 4.

In the fixed position stop control of the material, the calculation of the material moving distance is started after the tip of the material 1 is detected by the material sensor 9, and the material position result _Dstop (mm) obtained by the calculation is obtained.
The roller table 2 is stopped so that the material stops when the distance substantially shorter than the actual distance D _meas2 (mm) from the installation position of the material sensor 9 to the target stop position P of the material.
Speed control must be performed. Therefore, the position result correction circuit 12 performs the following operation on the material position result D _stop (mm) obtained by counting the pulses in the pulse counting circuit 11 and corrects the material position result D _comp (mm). ) Is added to the subtractor 13.

[0020] _{D comp = D stop × D meas1} / D count ... (2) That is, the material position actual D _{st op} calculated based on the speed detection value of the speed detector 7, measured between the material sensor 8,9 The material position result D _comp corrected using the ratio of the distance D _meas1 and the calculated distance D _count between the material sensors 8 and 9 calculated based on the speed result of the roller table driven by the drive device 6 is obtained. As a result, highly accurate fixed-position stop control can be performed regardless of the material shape.

Next, it is _assumed that a fixed material conveyance speed reference V _refo is given to the drive devices 4 to 6. Material 1
The timer circuit 15 detects the actual time T (sec) from the time when the material sensor 8 detects the front end of the material 1 until the time when the material sensor 9 detects the front end of the material 1, and uses the detected value as a speed reference. It is applied to the correction circuit 16. Here, the material sensors 8, 9
Since the measured distance between is _D meas1 (mm) As described above, the actual conveying velocity V _{ac t} (mm / sec) is calculated by the following equation. V _act = D _meas1 / T (mm / sec) ... (3)

This actual material transport speed V _act (mm / sec)
And the material transport speed reference V _refo (mm / sec) do not match due to a material slip or the like. To correct this, _assuming that the target speed is V _aim (mm / sec), the drive devices 4 to 6
If the speed reference V _ref given to is calculated by the following equation, the material 1 can be transported at a predetermined speed. V _ref = (V _aim / V _act ) × V _refo (4)

By the way, if the material has a slip,
The value of V _aim / V _act shown in the equation (4) becomes larger than “1.0”. Thus, the speed reference V _{re f} slip material is large there is a possibility that becomes excessive. Therefore, by providing an upper limit of the speed reference _{Vref in} the speed reference correction circuit 16 and adding a function of limiting and outputting this value, the corrected speed reference _Vref exceeds the maximum speed based on the rating of the motor. In such a case, the deviation between the speed reference and the actual speed can be prevented.

Further, by providing a means for alerting the operator when the speed correction ratio V _aim / V _act based on the slip of the material 1 exceeds a predetermined upper limit, it is possible to further improve the material transport and safety. Fixed position stop control can be performed.

In the above-described embodiment, the description has been given of the material conveying apparatus installed in the hot rolling line. However, the present invention is not limited to this, and a plurality of roller tables are serially arranged in the material conveying direction. It can be applied to most devices that are arranged and stop the material at the stop target position on the second and subsequent roller tables as viewed in the material transport direction.

[0026]

As is apparent from the above description, according to the first aspect of the present invention, the material is provided at the upper and lower ends of the roller table upstream of the roller table where the target stop position of the material is set. Calculation between the first and second material sensors calculated based on the actually measured distance between the first and second material sensors and the actual speed of the roller table downstream of the roller table where the target stop position of the material is set. Since the actual position of the moved material is corrected with reference to the installation position of the second material sensor using the ratio with the distance, the material transfer that enables highly accurate fixed-position stop control regardless of the material shape. An apparatus can be provided.

According to the second aspect of the present invention, the ratio between the actual speed based on the measured distance and the required time and the actual speed of the roller table downstream of the roller table where the target stop position of the material is set is used. Since the speed reference applied to the drive device is corrected, the effect that the material speed can be matched with the speed reference can be obtained.

According to the third aspect of the present invention, since a predetermined upper limit is set for the ratio between the actual speed of the material calculated based on the actually measured distance and the actual speed of the roller table detected, the speed reference and the speed are set. There is also obtained an advantage that it is possible to prevent deviations in the results.

According to the present invention, when the ratio between the calculated actual speed of the material and the actual speed of the roller table detected by the speed detecting means reaches a predetermined upper limit, the state is warned. Since the display is performed, there is an effect that the material can be transported and the fixed position stop control can be performed with further enhanced safety.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of a material conveying device according to the present invention.

FIG. 2 is a schematic configuration diagram of a conventional material transport device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Material 2 Roller table 3 Motor 4,5,6 Drive device 7 Speed detector 8,9 Material sensor 10A, 10B Material position control circuit 11 Pulse count circuit (Position actual detection means) 12 Position actual correction circuit 13 Subtractor 14 Speed Reference circuit 15 Timer circuit (time detection means) 16 Speed reference correction circuit

Claims (4)

[Claims] A plurality of roller tables are arranged in series in a material conveying direction, and the same speed reference is given to a drive device provided for each roller table, and the second and subsequent roller tables as viewed in the material conveying direction are provided. In the material transport apparatus for stopping the material at the upper stop target position, a first material sensor and a downstream end provided at the upstream end of the roller table upstream of the roller table where the target stop position of the material is set A second material sensor provided; speed detecting means for detecting the actual speed of the roller table downstream of the roller table on which a target stop position of the material is set; and the roller detected by the speed detecting means. Based on the actual speed of the table, the actual position of the moved material is detected based on the installation position of the second material sensor. Means, and a calculated distance between the first and second material sensors calculated based on an actually measured distance between the first and second material sensors and a speed result of the roller table detected by the speed detecting means. And a position result correcting means for correcting the position result of the material position detecting means using the ratio of the material position detecting means. 2. A time detecting means for detecting a time required for a material to pass between said first and second material sensors, and an actually measured distance between said first and second material sensors and a time detected by said time detecting means. The actual speed of the material is calculated based on the obtained material passing time, and the speed reference is corrected using a ratio of the obtained actual speed of the material and the actual speed of the roller table detected by the speed detecting means. The material transporting apparatus according to claim 1, further comprising: 3. A material conveying apparatus according to claim 2, wherein a predetermined upper limit is provided for a ratio between the calculated material speed result and the roller table speed result detected by said speed detecting means. apparatus. 4. When the ratio between the calculated actual speed of the material and the actual speed of the roller table detected by the speed detecting means reaches a predetermined upper limit, there is provided means for displaying a warning of the state. The material conveying apparatus according to claim 2, wherein: