JPH0211342B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing stranded wire for, for example, electric cables, and more particularly to a method for manufacturing stranded wire by combining a wire drawing machine and a stranding machine in tandem on the same line. It is.

In order to reduce the number of processes in order to lower the manufacturing cost of electric cables, a wire stranding manufacturing device has been proposed in which a multi-strand wire drawing machine and a buncher-type wire stranding machine are combined in tandem on the same line. In this device, there are two types of wire drawing machines: non-slip type and slip type.

In the non-slip type, a predetermined amount of wire is wound around the capstan to store the wire so that no slip occurs between the capstan and the wire, and by controlling the rotation of the capstan, the wire is taken up and drawn from each wire drawing die. In order to prevent the wire from becoming loose or becoming too tight between the wire drawing dies due to speed fluctuations in the wire, a wire speed adjustment mechanism and dicer rolls are provided between the wire drawing dies.

With the slip type, the wire is wound around the capstan only once or twice, which is the minimum number of times that the capstan can pull the wire, and the circumferential speed of each capstan (excluding the final capstan) is set higher than the drawing speed of the wire in that part. The wire is then drawn by driving and controlling the rotation of the capstan so that a slip occurs between the capstan and the wire. If the speed of the wire changes and the wire becomes loose between the wire drawing dies, the pressure force between the wire and the capstan between the dies becomes weaker (the pressing force of the wire against the capstan becomes weaker). Since the slip friction force is reduced, the force required to draw the wire from the preceding wire drawing die is reduced, and the slip rate between the capstan and the wire (the difference between the circumferential speed of the capstan and the drawing speed of the wire) is (representing the percentage of the value divided by the wire drawing speed) increases, and the drawing speed of the wire from the preceding wire drawing die decreases to absorb the slack in the wire.

On the other hand, if the wire rod is stretched too much between the wire drawing dies, the crimp force of the wire rod of the capstan between the dies becomes stronger due to the opposite effect to the above, and the crimp force of the wire rod from the previous wire drawing die becomes stronger. , the pulling force of the wire rod from the wire drawing die in the previous stage increases, the slip ratio between the capstan and the wire rod decreases, and the drawing speed of the wire rod from the wire drawing die in the front stage increases,
To relieve excessive tension of the wire rod.

In this way, the slip type wire drawing machine creates a slip between the capstan and the wire to prevent the wire from becoming loose or overtensioned, and to balance the tension in the wire.

However, in any type of wire drawing machine, the final capstan controls the drawing speed of the wire rod drawn by the final wire drawing die to a constant value and winds the wire rod onto the take-up reel with a constant tension. The circumferential speed of the final capstan is controlled so that no slip occurs between the capstan and the wire, that is, the circumferential speed of the final capstan matches the drawing speed of the wire.

This kind of thinking has traditionally been applied to wire stranding manufacturing equipment, in which a wire drawing machine and a wire twisting machine are arranged in tandem and operated at the same time to perform wire drawing and twisting operations continuously. Therefore, when a plurality of wire rods drawn by a wire drawing machine are twisted by a wire twisting machine, the tension of each wire rod may not be equal.

For example, in the case of 7-strand twisting, the twisting rate of the wire rods entering the center and the wire rods of the outer layer are different, so that the wire rods of the outer layer are picked up by the twisting machine faster than the wire rods entering the center. However, the outer diameter and circumferential speed of the final capstan of the wire drawing machine are all the same, and the drawing speed of each wire rod drawn at the final capstan is the same so as to prevent slipping. Wire drawing speed (peripheral speed of final capstan)
If the drawing speed of the outer layer wire is adjusted to the above-mentioned drawing speed of the outer layer wire, the tension balance between the wire entering the center and the outer layer wire will be disrupted, and the wire entering the center will fly out during twisting, causing the elongation of each wire drawn at the final capstan. When the wire speed (peripheral speed of the final capstan) is matched to the above-mentioned take-up speed of the wire entering the center, a larger tension acts on the outer layer wire than the wire entering the center, causing the outer layer wire to be stretched and reduced in diameter. However, no matter which method is selected, it is not possible to perform stable wire stranding work for a long time, and the twisted shape of the stranded wires becomes uneven, making it impossible to manufacture high-quality stranded wires.

For this reason, only the outer diameter of the final capstan on which the wire rod entering the center is hung is made smaller than the outer diameter of the final capstan on which the outer layer wire rod is hung.
There is a method in which the drawing speed of the wire entering the center (peripheral speed of the final capstan) is lower than the drawing speed of the outer layer wire (peripheral speed of the final capstan) so that the tension of both wires is balanced. (For example, see Japanese Patent Publication No. 54-22421.) Since the twisting ratio of the two wire rods is different when the size of the stranded wire to be manufactured is different, a large number of final capstans corresponding to the stranded wire to be manufactured are prepared and the wire drawing machine is used. It is necessary to attach and detach the device, which has the disadvantage of complicating the equipment.

In addition, since the final capstan is controlled to rotate so that no slip occurs between the final capstan and the wire rod, for example, when the wire stranding machine is started up,
If the wire grows rapidly during normal operation or stoppage, the wire will not be drawn at the final capstan and will be drawn directly by the stranding machine, which generally requires a large drawing force to draw the wire. Therefore, the pulling force of all the wires in the wire stranding machine becomes large in proportion to the number of wires, and unreasonable tension is applied to the stranding machine, which may reduce the performance of the stranding machine or cause the rotation of the stranding machine to increase. There are problems such as the cage being damaged and becoming unusable.

To prevent such problems from occurring,
It is also possible to control the tension by installing dancer rolls for each wire rod between the wire drawing machine and the wire twisting machine.
The capstan peripheral speed must be controlled independently for each wire rod in the wire drawing machine by electrically detecting the displacement of the dancer roll, and a motor or transmission is required for each head of the wire drawing machine. However, since dancer rolls corresponding to the number of wire rods are required, the equipment becomes large-sized and the equipment cost is high.

The purpose of the present invention is to apply tension in a well-balanced manner to each wire rod coming out of a wire drawing machine using simple and inexpensive equipment, so that the machine can be operated stably for a long period of time without trouble. To provide a stranded wire manufacturing method capable of efficiently manufacturing stranded wires of good quality with no elongation or loosening.

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 schematically shows the method of the present invention, in which a multi-strand wire drawing machine 12 and a buncher-type wire twisting machine 14 are installed on the same line. In the illustrated embodiment, the wire twisting machine 14 is shown to be stranding seven wires, and the seven wire rods 1 are set to a constant tension by a tension control roll 38 after leaving the wire drawing machine 12. A stranded wire is manufactured by twisting six outer layer wires around one center by a twisting machine 14 while maintaining the same.

The wire drawing machine 12 has six wire drawing dies 1 for each wire rod.
This is a known slip-type wire drawing machine in which six capstans 18 are alternately arranged in a straight line. Each capstan 18 is driven and controlled so as to generate a slip between each capstan 18 and each wire 1 at a drawing speed higher than that of each wire 1 drawn at step 16.

In FIG. 1, reference numerals 20 and 22 represent an entrance guide roll and an exit guide roll, respectively. 7
The main wire rod 1 is transferred from the entrance guide roll 20 to the wire drawing machine 1.
2, the wire rod 1' is drawn to have a predetermined outer diameter, and passes through an exit guide roll 22.

The wire twisting machine 14 has a rotating cage 2 in which the seven wire rods are
4 through the twisting cap 26, the guide roll 28, passing in the rotating cage 24 in an arcuate manner, passing from the guide roll 28' through the other twisting cap 26', and rotating at a constant speed with the number of revolutions of said cage 24. The capstan 30, which is rotationally driven at a constant speed, takes up the material at a constant take-up speed without slipping, passes through a guide roll 32 and a traverser 34, and winds it onto a take-up drum 36, during which time it is rotated by the twisting caps 26, 26'. One rotation of the cage 24 results in two twists. Incidentally, the twist cap 26' may be omitted depending on the case.

In the method of the present invention, the circumferential speed y of the final capstan 18A of the wire drawing machine 12 is calculated as y=ax+A (a is a proportional constant, a≧1, A is a bias, A>0) with respect to the take-up speed x of the wire twisting machine 14. It should be controlled based on the relationship between

Generally, in a wire drawing machine, the frictional force between the wire drawing die and the wire is large, and a large drawing force is required to draw the wire. In particular, the startup of the wire drawing machine 12 is delayed compared to the wire twisting machine 14 when starting up, and conversely, when the wire drawing machine 12 is stopped, the wire twisting machine 14
There is a tendency that it is difficult to synchronize the speeds of the wire drawing machine 12 and the wire twisting machine 14, such as the wire drawing machine 12 stopping earlier than in the previous example. Therefore, the final capstan 1 of the wire drawing machine 12
By applying bias A to a circumferential speed of 8A,
When starting and stopping, the circumferential speed is increased by about 15% (slip rate 15%) than the take-up speed of the stranding machine 14, and during normal operation, the circumferential speed is increased according to the above relationship ax + A, (slip rate (reduced to about 5%), the final capstan 18A is driven and controlled so that the wire rod 1' taken off by the final capstan 18A is always taken off by the frictional force caused by the slip between the wire rod 1' and the final capstan 18A.

When the slip is caused in this way, the drawing speed of the wire rod 1' drawn at the final capstan 18A becomes equal to the drawing speed of the wire twisting machine 14, and the wire rod 1' between the final capstan 18A and the wire twisting machine 14 has a
An appropriate pulling force acts on the wire rod 1' in the twisting machine 14 to produce a high quality stranded wire.

That is, when the stranding machine 14 takes over the wire 14 at a higher speed than the drawing speed of the wire 1' when the stranding machine starts up, normally operates, or stops,
The compression force between the final capstan 18A and the wire 1' becomes stronger, and the slip rate between them becomes smaller.
The pulling force for drawing the wire rod 1' from the final wire drawing die tends to increase, but when this happens, the wire rod 1' becomes loose between the final capstan 18A and the wire twisting machine 14, so the final capstan 18
At point A, the force for drawing the wire 1' becomes weaker and the drawing speed decreases, so the drawing speed of the wire 1' only increases until it becomes equal to the drawing speed of the wire twisting machine 14, and the drawing speed of the wire 1' increases. The wire is always taken off at the final capstan 18A at a drawing speed equal to the drawing speed of the wire twisting machine 14.

On the other hand, when the take-up speed of the wire stranding machine 14 becomes relatively small with respect to the drawing speed of the wire rod 1', the pressure force between the final capstan 18A and the wire rod 1' becomes weaker, and the slip between the two becomes weaker. As the ratio increases, the pulling force for drawing the wire rod 1' from the final wire drawing die tends to decrease. Since it is coming, the final capstan 18
At point A, the force for drawing the wire rod 1' becomes stronger and its drawing speed increases, so the drawing speed of the wire rod 1' only decreases until it becomes equal to the drawing speed of the wire twisting machine 14, and the drawing speed of the wire rod 1' increases. The wire is always taken off at the final capstan 18A at a drawing speed equal to the drawing speed of the wire twisting machine 14.

Although the drawing speed of the wire 1' drawn by the stranding machine 14 is different between the wire entering the center and the wire in the outer layer (the former is slower than the latter due to the difference in the twisting rate of the stranded wire), The circumferential speed of the wire rod 18A is always higher than the take-up speed of each wire rod 1' in the twisting machine 14, and there is always a slip between the final capstan 18A and the wire rod 1', so the wire rod 18A is taken up by the final capstan 18A and enters the center. The drawing speed of the wire rod 1' is equal to the drawing speed of the wire rod 1' drawn by the wire twisting machine 14 and entering the center, and the drawing speed of the outer layer wire rod 1' drawn by the final capstan 18A is equal to the drawing speed of the wire rod 1' drawn by the wire twisting machine 14. The drawing speed is equal to the drawing speed of the outer layer wire 1' which is drawn at 1, and there is no problem of the wire entering the center being thrown out during twisting or the diameter of the outer layer becoming thinner. In addition, since the wire is not directly picked up and drawn by the stranding machine, no excessive tension is applied to the stranding machine, which may reduce the performance of the stranding machine or damage the rotating cage of the stranding machine, rendering it unusable. This eliminates problems such as .

However, the final capstan 18A of the wire drawing machine 12
When the drawing speed of the wire rod 1' to be drawn at the wire rod 1' increases or decreases, in the non-slip type wire drawing machine, the wire speed adjusting mechanism or the dancer roll is used to draw the wire rod 1' before the final capstan 18A as described above in the slip type wire drawing machine. The circumferential speed of each capstan 18 on the side is higher than the wire drawing speed of the wire rod, and a slip always occurs between them. Needless to say, tension imbalance can be prevented.

In addition, after the stranded wire manufacturing device is started, the peripheral speed y of the final capstan 18A of the wire drawing machine 12 is determined by the relationship y=ax+A (a is a proportional constant, a≧1, A is the bias A>0). If the drive is controlled to be higher than the take-up speed of the wire rod, as described above, it is possible to prevent tension imbalance due to speed fluctuations of the wire rod, but it is also possible to prevent the slip rate between the final capstan 18A and the wire rod 1' during normal operation. Since the slip rate is smaller than the slip rate during high-speed operation, it becomes easier to control the wire tension during high-speed operation.

For example, seven wire rods 1' made of copper wire with an outer diameter of 1 mm drawn by the wire drawing machine 12 are twisted together to have a twist pitch of 38 mm.
When producing stranded wire, the stranding machine 14 during normal operation
If the rotation speed of the rotation cage 24 is 1200 rpm,
The take-off speed of the wire twisting machine 14 is 91.2 m/min (this refers to the take-off speed of the wire 1' that normally enters the center). Therefore, the peripheral speed y of the final capstan 18A is y = 1.044x +
If the relationship of 0.53 (experimental formula) is selected, the circumferential speed of the final capstan 18A during normal operation is
Since the speed is 95.7m/min, the slip rate during normal operation is 4.9%.

On the other hand, if the cage rotation speed at startup is 66 rpm, the take-up speed of the stranding machine is 5 m/min. Therefore, if the circumferential speed y of the final capstan 18A is selected to satisfy the relationship in the above formula, the circumferential speed of the final capstan 18A at startup will be 5.57 m/min.
The slip rate at startup is 15%.

Note that the wire rods forming the outer layer of the stranded wire have a 1.2% higher take-up speed than the wire rods entering the center due to the twist ratio, but since the final capstan 18A is set to rotate at the same number of revolutions, the outer layer The circumferential speed of the final capstan 18A that takes over the wire is the same as the circumferential speed of the final capstan 18A that takes over the wire that enters the center, that is, 95.7 m/min during normal operation.
At startup, it is 5.75m/min. Therefore, the slip rate of the outer layer wire 1' at the final capstan 18A decreases slightly, to 3.7% during normal operation and 12.7% during startup.

By the way, when the take-off speed of the wire twisting machine 14 increases rapidly during normal operation, the pressure force between the final capstan 18A and the wire rod 1' increases as described above, and the wire drawing speed of the wire taken off from the final capstan 18A increases. However, since the wire drawing speed itself during normal operation is already high, the degree of increase in the wire drawing speed is large, and the wire drawing speed becomes too high, causing the wire rod 1'
becomes loose and becomes detached from the final capstan 18A, making it impossible to take it back, or after the wire drawing speed increases, the wire drawing speed suddenly decreases, which tends to cause hunting in the control system. It is difficult to control the tension of the wire. However, in the present invention, the slip ratio between the final capstan 18A and the wire 1' during normal operation is smaller than the slip ratio during startup, so the relative speed between the two becomes smaller, making it difficult for the wire to come off or hunt. The tension of the wire rod 1' between the final capstan 18A and the stranding machine 14 is stabilized, and the wire rod 1' is neither too tensioned nor too loose, allowing stable high-speed operation for long periods of time, improving the production capacity of stranded wire. can do.

FIG. 2 shows one embodiment for carrying out the method of the invention, in which the take-off speed x of the wire twisting machine 14 is removed from the tension control rolls 38 and Drive motor 4
0 is controlled. A take-up speed signal Sx corresponding to the take-up speed x is detected from the tension control roll 38 via a belt transmission mechanism 42 by a rotation speed detector 44.

The slope of this take-up speed signal Sx is changed by a variable resistor _VR1 in a range of about 0 to 15% to obtain a variable slope signal Sax corresponding to ax. The arithmetic circuit 44 adds a bias signal S _A corresponding to the bias A generated from the variable resistor VR ₂ to the variable slope signal Sax to generate a control signal Sy corresponding to ax+A, and controls the drive motor via the start/stop switch 46. 40 drive circuits 48. Therefore, the drive motor 40 drives each final capstan 18A of the wire drawing machine 12 at y=
It is driven by a drive circuit 48 to set the peripheral speed to the same controlled speed of ax+A. In FIG. 2, the reference numeral 49 is a gear transmission mechanism that drives the final capstan 18A from the drive motor 40, and the reference numeral 50 is a rotation speed detector of the drive motor 40, the signal of which is fed back to the drive circuit 48 and used as a control signal. Sy
The rotary motor 40 is driven at a predetermined rotation speed.

FIG. 3 shows how the circumferential speed y of the final capstan 18A of the wire drawing machine 12 changes depending on the operation of the stranded wire manufacturing apparatus according to the method of the present invention, where the dotted line a indicates y=x and the broken line b is y=ax, solid line c is y=ax
The cases controlled by +A are shown respectively. In this figure, in case a, at startup, during normal operation,
There is a risk that the tension will become excessive when stopped.
In case b, there is a risk that the tension will become excessive at the time of starting and stopping, but in case c of the present invention, the peripheral speed of the capstan is maintained not only during normal operation but also during starting and stopping as described above. is made higher than the take-up speed of the wire twisting machine so that a slip occurs between the wire being taken off at the final capstan and the capstan, so that the tension does not become excessive and no unreasonable force is applied to the wire twisting machine. There is no. In addition, in FIG. 3, t is the final capstan 18 due to bias A.
Indicates the time by which the stop of A is delayed.

The following table shows that when seven wires 1' of mm ² are twisted together,
Each final capstan 18A of the wire drawing machine 12 is set to y=1.03x+ for the tension control roll circumferential speed x (take-up speed).
Examples of driving at peripheral speeds (P, Q) of 1.1 and y=x+2.8 are shown, and in both cases, continuous and stable operation was possible.

table Although the take-up speed x was taken out from the tension control roll 38, the capstan 3
It may be taken out from 0 or from another roll that engages the wire 1' or the stranded wire. Furthermore, the take-up speed of the wire stranding machine is not limited to the speed at which a single strand itself is taken off after being twisted by the stranding machine; It may be the running speed of the outer layer wire in the case of a stranded wire with an incoming wire, or each wire in a set stranded wire without an incoming wire. Further, in the embodiments of the present invention, a wire drawing machine that hangs one wire rod for each capstan (including the final capstan) has been described, but a device that hangs each wire rod on one common capstan may also be used. This is particularly effective when the number of wire rods to be twisted is small.

According to the present invention, in the wire stranding manufacturing method in which a multi-strand wire drawing machine and a bunchier-type wire stranding machine are combined on the same line to continuously strand a plurality of wire rods after drawing, the stranding machine The peripheral speed y of the final capstan of the wire drawing machine is determined by the relationship y=ax+A (a is a proportional constant, a≧1, and A is a bias, A>0) for the take-off speed x of the wire stranding machine. The final capstan is driven and controlled so that the wire drawn at the final capstan is always pulled by the frictional force generated by the slip between the final capstan and the final capstan, and the drawing speed of the wire stranding machine is adjusted to match the final capstan of the wire drawing machine. When the drawing speed is relatively higher than the drawing speed of the wire, the crimping force between the final capstan and the wire becomes stronger and the slip ratio between them becomes smaller, making the drawing speed of the wire equal to the drawing speed of the wire stranding machine. When the drawing speed of the wire twisting machine becomes relatively smaller than the drawing speed of the wire drawn at the final capstan of the wire drawing machine, the crimping force between the final capstan and the wire becomes weaker, causing slippage between them. By decreasing the wire drawing speed until it becomes equal to that of the wire twisting machine, the drawing speed of the wire drawn at the final capstan becomes equal to the drawing speed of the wire twisting machine.

Therefore, when multiple wire rods drawn by a wire drawing machine are twisted by a wire twisting machine, even if the take-up speed of the wire entering the center and the wire rod of the outer layer is different due to the difference in twisting rate, the wire drawing machine The tension of each wire rod between the final capstan and the wire twisting machine becomes equal, and the wire rods entering the center will not fly out during twisting, and the wire rods in the outer layer will not be stretched and become thinner, resulting in good twisted appearance. Wires can be manufactured stably for a long time.

In addition, there is no need to prepare a large number of final capstans that match the size of the stranded wire to be manufactured, or to install a dancer roll for each wire between the wire drawing machine and the stranding machine to control the tension, making the equipment simpler and smaller. Therefore, equipment costs are also low. Furthermore, when the stranding manufacturing equipment is started up, during normal operation, or when it is stopped, even if the drawing speed of the stranding machine is relatively high compared to the drawing speed of the wire drawn at the final capstan, each wire cannot be stranded. Since the wire is not directly picked up and drawn by the wire twisting machine, no excessive force is applied to the wire twisting machine, and the performance of the wire twisting machine can be maintained for a relatively long time.In addition, the rotating cage is free from damage such as breakage. The system does not become unusable due to damage, the failure rate is reduced, and maintenance is easy.

Furthermore, the slip rate between the final capstan and the wire is smaller during normal high-speed operation than during startup and stop, so the wire may come off from the final capstan or the control system may become hunting even during normal operation. The tension of the wire between the final capstan and the stranding machine is stabilized, and stable high-speed operation is possible for a long period of time, which improves the production capacity of stranded wire.

[Brief explanation of drawings]

FIG. 1 is a schematic system diagram showing an embodiment of the present invention;
FIG. 2 is a circuit diagram showing an example of a control system used in the present invention, and FIG. 3 is a diagram showing the method of the present invention in terms of circumferential speed of the final capstan versus time. 1,1'... wire rod, 12... wire drawing machine, 14...
Stranding machine, 18A...Final capstan.

Claims (1)

[Claims] 1. In a stranded wire manufacturing method in which a multi-strand wire drawing machine and a bunchier-type wire stranding machine are combined on the same line to continuously strand a plurality of wire rods after drawing, the drawing speed x of the stranding machine is On the other hand, the circumferential speed y of the final capstan of the wire drawing machine is y=ax+A (a is a proportional constant and a≧
1. A is the bias (A>0), and the drawing speed is set higher than the wire twisting machine so that the wire drawn at the final capstan is always drawn by the frictional force caused by the slip between this and the final capstan. When the final capstan is driven and controlled, and the take-off speed of the wire twisting machine becomes relatively higher than the drawing speed of the wire taken by the final capstan of the wire drawing machine, the crimping force between the final capstan and the wire becomes stronger, causing a gap between the two. The slip rate of the wire becomes smaller, and the wire drawing speed is increased until it becomes equal to the drawing speed of the wire stranding machine, and the drawing speed of the stranding machine is relative to the drawing speed of the wire drawn at the final capstan of the wire drawing machine. When the wire rod becomes smaller, the crimping force between the final capstan and the wire becomes weaker, and the slip rate between them increases. A method for manufacturing a stranded wire, characterized in that the drawing speed of the wire being drawn is equal to the drawing speed of a stranding machine.