JPH07105768A - Control method for vertical type continuous valcanizing machine for electric power cable - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a runaway accident to increase follow-up performance at the time of a rise by adjusting the pulling tension of a traveling thread body through adjusting a pulling speed, and changing set tension in accordance with a traveling thread length to control the wire tension in the outlet of a valcanizing machine. CONSTITUTION:A conductor 2 delivered from a delivery device 1 is sent to an extruding head 4a by a delivering machine 3, an insulated body from extruders 4A... is coated and then is valvanized by a valcanizing machine 5, and the traveling wire thread body W of an obtained coated electric wire is wound by a winder 7 via a pulling machine 6. At that time, the tension of the traveling wire thread body W is detected by a tension sensor 8 to adjust a pulling speed via a controller 9 in accordance with a detected value. In a control method for the vertical type continuous valcanizer of the electric power cable, pulling tension is corrected via a pulling speed, and also is changed in accordance with the thread length of the traveling wire thread body W from starting time of a line to give wire tension in the reverse direction to the proceeding direction of the valcanizer 5 even after passing the outlet of the valcanizer 5. Consequently the variation of a line wire bundle can be restrained to follow to wire tension change.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a vertical type continuous vulcanizer for a power cable, and more particularly to a line for manufacturing a power cable by extruding an insulating material onto a conductor in a running state and coating the same. It improves the operability at the start of operation.

[0002]

2. Description of the Related Art In a line for producing a power cable by coating a conductor in a running state with a rubber / plastic insulating material, an insulating material is extruded from an extruder and coated on a conductor fed from a conductor feeding device and a feeder. However, the coating thickness on the conductor is set by the line linear velocity, the extrusion amount of the insulating material, and the like.

At the start of the operation of the line for producing a power cable, the conductor is connected to the lead wire, and the lead wire portion is guided to the line, that is, the conductor feeding device, the feeder, the extruder, the vulcanizer, These devices are sequentially activated through a take-up machine, a take-up machine, and the like, and in particular, the line linear velocity and tension between the feeder, the vulcanizer, and the take-up machine are appropriately adjusted.

For example, a desired linear line speed is set by a feeder, and the extrusion speed of the extruder is set in accordance with the linear line speed to make the coating thickness on the conductor constant and It is necessary to equilibrate the take-up speed of the take-up machine corresponding to the line linear velocity and keep the line tension constant. In this case, the line linear velocity is set by the feeding speed in the feeder, the lead wire in the take-up machine,
It is carried out by detecting the take-up speed of the cable and the like and sequentially correcting the take-up machine speed with reference to the speed of the sending machine.

On the other hand, at the time of starting the line, the line linear velocity is in an accelerating state, and the tension changes with the change of the line linear velocity. The phenomenon that the coating thickness becomes unstable tends to occur.

[0006] Further, the vulcanizer of the power cable manufacturing line is generally large, and in the case of the vertical vulcanizer, the distance between the feeder and the take-up machine is often several tens of meters, and the line linear velocity is high. It is relatively slow, often 10s of cm to several meters per minute. Therefore, when the insulating material is coated on the extruder immediately downstream of the feeder, it takes about several tens of minutes until the portion passes through the vulcanizer and reaches the take-up machine.

Therefore, when performing the tension adjustment,
For example, the necessary number of workers are attached to important points of the line, and fine adjustment is sequentially repeated based on the experience and intuition of the worker so as to keep the tension of the linear body constant. Also, by computer technology, for example, P
I control is performed to set the target value of the tension, the tension near the take-up machine is sequentially detected, and the take-up speed of the take-up machine is adjusted based on the detected tension value. A method of approximating the detected tension value by using the above method is also conceivable.

[0008]

However, in the case of the tension adjusting method based on the experience and intuition of the former operator, not only the labor becomes great, but also the cable core becomes constricted and the quality varies due to individual differences. The latter PI control method has a difficulty, and as described above, the time from adjustment to the detection of the result is, for example, several tens of seconds based on the long line distance and the slow line linear velocity. There is still a problem to be solved, such as the possibility that the line linear velocity may fluctuate more than necessary to cause a runaway and the safety may be impaired due to the automatic delay (time lag), or the hunting phenomenon that repeatedly increases and decreases may occur. .

The present invention has been made in view of the above circumstances, and suppresses the fluctuation of the line linear velocity to prevent the occurrence of a runaway accident, and the followability to the change of the linear tension at the start of the power cable manufacturing line. The purpose is to increase

[0010]

In a method of controlling a vertical type continuous vulcanizer of a power cable according to the present invention, a conductor sent from a feeder is extruded and covered with an insulating material from an extruder to cover the power cable. When manufacturing the product, when the tension of the traveling linear body is detected and the take-up speed of the traveling linear body is increased or decreased depending on the magnitude of the tension, whether the take-up tension is within the set tension range or not. Whether the pulling tension is out of the range is corrected by increasing or decreasing the pulling speed of the running linear body, and the set tension is changed according to the length of the linear body from the start of the line. Thus, even after the filament has passed through the outlet of the vulcanizer, the linear tension is controlled so as to be applied to the filament in a direction opposite to the traveling direction. In addition to these, when a threshold value range is set for the set tension, and the detected tension is within the threshold range rather than the correction degree of the take-up speed when the detected tension is outside the threshold range. The travel speed is corrected by reducing the correction degree of the take-up speed.

[0011]

[Operation] When the detected tension is out of the range of the threshold value, the take-up tension is corrected by increasing or decreasing the take-up speed, and the take-up tension is changed according to the length of the running linear body from the start of the line. This limits the increase in linear tension when passing through the outlet of the vulcanizer, that is, the packing portion, and prevents the occurrence of constriction. Further, the degree of correction of the take-up speed is gradually reduced according to the range of the threshold value in the set tension to reduce the fluctuation range of the take-up speed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a control method for a vertical type continuous vulcanizer of a power cable according to the present invention will be described below with reference to FIGS.
It will be described based on.

In each drawing, reference numeral 1 is a conductor feeding device, 2
Is a conductor, 3 is a feeder, 4A, 4B and 4C are extruders, 5 is a vulcanizer, 6 is a take-up machine, 7 is a take-up machine, 8 is a tension sensor, 9
Is a controller, 10 is tension setting means, 11 is conductor feeding speed setting means, 13 is conductor feeding speed setting means, 14A,
14B and 14C are extrusion speed setting means, 16 is a filament drawing speed setting means, and 17 is a filament winding speed setting means.

Even in the embodiment, the plastic insulating material is coated on the running conductor 2 to be applied to a line for producing a covered electric wire (running wire body) W. The tension of the body W is detected by the tension sensor 8 and the take-up speed of the traveling linear body W is increased / decreased according to the magnitude of the tension, but the technique described below is added to these.

First, an outline of a power cable manufacturing line will be described. The conductor 2 is fed by the conductor feeding device 1, the traveling speed of the conductor 2 is set by the feeder 3, and the molten plastic insulating material is coated on the running conductor 2 in the extrusion head 4a of the extruders 4A, 4B, 4C. Then, vulcanization and cooling are performed by guiding the vulcanizer 5.
The traveling filament W coated with the desired coating is taken up by the take-up machine 6 while adjusting the tension, and the traveling filament W is stored in the winding machine 7.

In these manufacturing lines, when the line is started, the conductor 2 is connected to the lead wire and the conductor 2 is inserted at least downstream of the extrusion head 4a. .

In the conductor feeding device 1, the feeding speed of the conductor 2 is adjusted to the feeding speed of the conductor 2 by the operation of the conductor feeding speed setting means 11.
By the data transmission of the line linear velocity detecting means 13d in 3, the setting for adjusting the feeding speed to the line linear velocity is made.

In the sending machine 3, the line drawing speed is set by the operation of the conductor sending speed setting means 13. The conductor feeding speed setting means 13 operates the feeder drive motor 13a to set the feeding speed of the conductor 2 and the line linear velocity detecting means 13d detects the feeding speed, and the conductor feeding speed setting means 11 and the pushing speed setting means. 14A, 14B, 14C, filament drawing speed setting means 16
To transmit. Then, the rotation speed of the delivery device drive motor 13a is set by the line linear velocity setting device 13c with the delivery device drive amplifier 13b interposed.

In the extruders 4A, 4B and 4C, the extrusion speed (coating thickness) of the insulating material forming the inner layer, the main insulating layer and the outer layer is set by the operation of the extrusion speed setting means 14A, 14B and 14C. To be done. At this time, the coating speed of the insulating material is kept constant by adjusting the extrusion speed of the insulating material according to the line linear velocity by the conductor delivery speed setting means 13. In addition, downstream of the extrusion head 4a,
Outer diameter measuring means 4b for measuring the outer diameter of the traveling filament W covered with the insulating material is arranged, and the outer diameter measuring means 4b is provided.
The detection data of is also fed back to the extruders 4A, 4B and 4C.

In the take-up machine 6, the take-up speed of the traveling line body W is increased or decreased in accordance with the line linear speed by the operation of the line body take-up speed setting means 16, and the tension sensor 8 is also provided.
Adjustment is performed with consideration of the detection data of. The take-up machine drive motor 16a in the filament take-up speed setting means 16 sets the take-up speed of the traveling line body W, and the take-up speed detecting means 16d detects the take-up speed to rotate the take-up machine drive motor 16a. The speed is set by the take-up speed setting device 16c with the take-up machine driving amplifier 16b interposed. At this time, a detection signal from the line linear velocity detecting means 13d in the conductor sending speed setting means 13 and a control signal via the controller 9 by the tension setting means 10 described later are transmitted to the take-up speed setting device 16c. .

In the winding machine 7, the winding speed of the traveling linear body W is adjusted to the winding speed by the operation of the winding speed setting means 17 of the linear body.

On the other hand, at the time of starting the line, it is not enough to control the tension to be constant by changing the pulling force of the pulling machine 6. That is, as mentioned above,
When the vulcanizer 5 is large and the line linear velocity is low at the time of starting the line, even if the outer diameter of the traveling filament W is measured at the position of the extrusion head 4a in FIG. It takes several tens of seconds for the point to reach the position of the tension sensor 8, and each condition of the formula (1) may change within that time. Therefore, the thickness of the insulating material coating layer For the purpose of keeping constant, a special control method as shown in FIGS. 2 to 4 is adopted.

In the tension setting means 10 shown in FIG. 1, the pulling force (pulling tension) of the pulling machine 6 is set and calculated by the controller 9 from the relationship with the tension detected by the tension sensor 8. The stepping motor 16e is operated and the take-up speed setting device 16c is electrically adjusted to operate the stepping motor 16e. However, as shown in FIG. When the detected tension is within the threshold value Y, the take-up speed is controlled to increase or decrease with a speed adjustment value slightly smaller than that outside the threshold value. The speed adjustment value will be described later.

When such control is performed by changing the set tension of the tension setting means 10 according to the length of the filament, the conductor length and the linear tension are increased in the take-up direction, that is, the traveling direction of the conductor. As shown by S1 to S4 in FIG. 3, the relationship between and changes stepwise with time.

Here, the linear tension will be described. The linear tension mentioned here is a combined force of the tension acting on the take-up side and the tension acting on the sending side in the central portion of the feeder 3 in FIG. 1, and is expressed by the following equation. Line tension = force in the take-up direction (stripe weight + take-up tension + piston effect) -force in the send direction (conductor weight + send-out tension + buoyancy inside the vulcanizer) Equation (1) Here, the piston effect Is the pushing force due to (change in) the internal pressure applied to the cross-sectional area of the filament when the filament passes through the packing part at the exit of the vulcanizer, and the feeding tension corresponds to the braking force of the feeder 3. The buoyancy inside the vulcanizer is the buoyancy acting on the filament by the cooling water.

FIG. 4 shows a model of the control situation from the start of the line to the stable production of the power cable.
This depends on the type of cable, but the one shown here is when the conductor 2 is 1200 mm ² and the transmission output is 1
50 kg, the take-up force is 400 to 200 kg, the elapsed distance after starting until the insulating material coating layer passes through the seal packing 5a is 60 m, and the insulating material coating layer rises downstream of the take-up machine 6 and then faces downward ( The passing distance to the passing roller is 110 m.

The change in the linear tension in the example of FIG. 4 will be explained. At the time of starting the line, the set take-up tension is 400 k.
The tension when it is g is minus 750 kg, and as the traveling linear body W (or the conductor 2) travels, the traveling linear body weight increases, so that the tension shifts to the plus direction, and after traveling 10 m. The take-off force was reset to 350kg, and thereafter, as the mileage increased,
g, 250 kg, 200 kg, and the final take-up tension was 200 kg. By passing the insulating material coating layer through the seal packing 5a after traveling 60 m,
Although the tension sharply increases based on the equation (1), even in that case, a predetermined negative value (that is, a predetermined linear tension is applied in the delivery direction) is maintained. Furthermore, run 1
After 10 m and 120 m, the tension value became stable.

In these control methods, the reason why the linear tension is maintained at a predetermined value in the direction opposite to the feeding direction, that is, the traveling direction of the filament is that the linear tension is zero (the feeding direction and the take-up direction are balanced. This is because, if it is applied in a state) or slightly in the take-up direction, a disturbance (for example, a pressure fluctuation of the vulcanization cylinder) causes a speed fluctuation, and a constriction easily occurs.

Further, the control method shown in FIG. 4 will be described in detail. The change in the tension of the traveling linear body at the time of starting the line is as shown in the above equation (1). Occurs in relation to the conductor length). When the set value of the wire tension when the conductor length is 0 m is set to 750 kg, for example, the speed of the take-up machine is adjusted so that the take-up tension becomes 400 kg, but if the take-up speed continues to take up the running linear body, Drawing tension of 400kg 400kg
In the part where the conductor is longer than 60 m, the line tension exceeds zero and enters the constriction generation zone.
The phenomenon occurs.

Therefore, if the take-up tension by the take-up machine is changed to 350 kg for a conductor length of 10 m, 300 kg for a conductor length of 20 m, 250 kg for a conductor length of 30 m, and 200 kg for a conductor length of 40 m, depending on the conductor length, The curve shown by the thick solid line in FIG. 4 shows that even if the line tension increases due to the effect of the piston at the conductor length of 60 m, the line tension is maintained at a predetermined value in the delivery direction, and the "constriction" phenomenon occurs. Can be prevented. Note that, in FIG. 4, the relationship between the linear tension and the conductor length is expressed in a sawtooth shape based on the switching of the take-up tension, but by setting the threshold value, as shown in FIG. It changes slowly.

Then, for example, in FIG. 4, the speed adjustment value outside the threshold value Y and inside the threshold value Y is ± per second.
It is set to 0.0033 m and ± 0.01 m per second. As a result, the fluctuation of the take-up tension in the take-up machine becomes gentle (see FIG. 3), and the set value of the linear tension is changed according to the strip length as shown in FIG. The thickness of the insulating coating layer of the covered electric wire can be controlled to be constant.

[0032]

According to the control method of the vertical continuous vulcanizer for the electric power cable of the present invention, the following effects can be obtained. (1) It is determined whether the detected tension is within the set tension range, and if the detected tension is out of the range, the take-up tension is corrected by increasing or decreasing the take-up speed of the traveling linear body, and the set tension is started on the line. By changing it according to the length of the filaments from time to time, even after the filaments have passed through the outlet of the vulcanizer, linear tension is applied to the filaments in the direction opposite to the traveling direction. By controlling, it is possible to suppress the occurrence of the "constriction" phenomenon in which the insulation coating thickness of the manufactured coated electric wire is partially thinned, reduce defects in the coated electric wire, and obtain a high-quality power cable. (2) It is possible to prevent the occurrence of a runaway accident by gradually reducing the correction rate of the take-up speed based on the range of the threshold value in the set tension to reduce the fluctuation range of the take-up speed.

[Brief description of drawings]

FIG. 1 is a connection diagram showing an embodiment of a method for controlling a vertical continuous vulcanizer for a power cable according to the present invention.

FIG. 2 is an implementation model diagram of three-position control by the tension setting means shown in FIG.

3 is a relationship curve diagram between time and tension increase by the three-position control of FIG.

FIG. 4 is a curve diagram modeling a control situation by a control method of a vertical type continuous vulcanizer of a power cable according to the present invention.

[Explanation of symbols]

 W coated electric wire (running filament) 1 conductor feeding device 2 conductor 3 feeder 4A, 4B, 4C extruder 4a extrusion head 4b outer diameter measuring means 5 vulcanizer 5a seal packing 6 take-up machine 7 winder 8 tension sensor 9 controller 10 tension setting means 11 conductor feeding speed setting means 13 conductor feeding speed setting means 13a feeder driving motor 13b feeder driving amplifier 13c line linear velocity setting device 13d line linear velocity detecting means 14A, 14B, 14C extrusion velocity setting means 16 Filament body take-up speed setting means 16a Take-up machine drive motor 16b Take-up machine drive amplifier 16c Take-up speed setter 16d Electric motor 16e Step motor 17 Filament body take-up speed setting means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toraichi Ishikawa 1800 Kishioka-cho, Suzuka-shi, Mie Fujikura Suzuka Co., Ltd. (72) Toshiharu Katsuhara 1800 Kishioka-cho, Suzuka-shi, Mie Fujikura Suzuka Co., Ltd. in the factory

Claims (2)

[Claims] 1. A conductor (2) sent from a sender (3)
When a power cable is manufactured by extruding and covering an insulating material from the extruder (4A, 4B, 4C), the tension of the traveling filament (W) is detected and the traveling filament is determined by the magnitude of the tension. It is a control method of a vertical continuous vulcanizer for electric power cables that increases or decreases the take-up speed, determines whether the take-up tension is within the set tension range, and when the take-up tension is outside the range, The linear body (W) is corrected by increasing or decreasing the take-up speed of the linear body, and the set tension is changed according to the length of the traveling linear body from the start of the line. A control method for a vertical continuous vulcanizer of a power cable, which is controlled so that a linear tension is applied to the linear body (W) in a direction opposite to its traveling direction even after passing. 2. A take-up value when the detected tension is within the threshold range rather than a correction degree of the take-up speed when the detected tension is outside the threshold range by setting a threshold range for the set tension. The method for controlling a vertical continuous vulcanizer of an electric power cable according to claim 1, wherein the traveling speed is corrected by reducing the correction degree of the speed.