JP2011258506A - Method for producing electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an electric wire that facilitates simultaneous production of two electric wires with a target outer diameter and simultaneous termination of production thereof.SOLUTION: The method for producing an electric wire comprises a process S02 for determining an average value Dx of outer diameters D1 and D2 of electric wires C1 and C2 respectively; a process S04 for increasing or decreasing an extrusion flow rate of a resin to match the average value Dx with a target outer diameter D; processes S05 and S06 for increasing or decreasing a linear velocity of the electric wire C2 so that its outer diameter D2 is within a prescribed tolerance if the outer diameters D1 and D2 are out of the prescribed tolerance; a process for increasing or decreasing the linear velocity of the electric wire C2 in the opposite direction from the increasing or decreasing in S05 and S06 when the outer diameters D1 and D2 are within the prescribed tolerance resulting from continued process S04 for increasing or decreasing the extrusion flow rate and continued processes S05 and S06 for increasing or decreasing the linear velocity; and a process for matching the linear velocity of the electric wire C2 with that of the electric wire C1 when the electric wires C1 and C2 produced are identical in size.

Description

  The present invention relates to a method of manufacturing an electric wire in which a wire such as a conductive wire is covered with a resin.

  As a method of manufacturing an electric wire in which a wire is coated with a resin, the resin is melted by an extruder, and a plurality of branch supply paths and each branch supply path are supplied to a plurality of extrusion molding parts including dies and nipples provided in a cross head. Resin is supplied through a cylindrical resin supply channel that communicates, and the linear body is passed through the holes of each die, and the resin is simultaneously applied to the outer periphery of each linear body, thereby covering a plurality of wires, etc. What manufactures a body is known (for example, refer patent document 1).

JP 2007-207514 A

In the above manufacturing method, the amount of resin supplied to each resin supply flow path is adjusted by the flow rate adjustment mechanism so that the outer diameter of each electric wire becomes the target outer diameter, but without providing the flow rate adjustment mechanism. It is desired that the outer diameter of each electric wire be easily set as the target outer diameter.
Moreover, when manufacturing the electric wire of the same set length, if one of the electric wires is manufactured first, the resin supplied to one of the extrusion molding units is wasted until the other electric wire is manufactured. Therefore, it is desired to finish the production of electric wires having the same set length as much as possible.

  The objective of this invention is providing the manufacturing method of the electric wire which can manufacture simultaneously the two electric wires of a target outer diameter easily, and can match the completion | finish timing of manufacture.

The method of manufacturing an electric wire according to the present invention that can solve the above-mentioned problem is that a resin is fed into a pair of extrusion molding parts by an extruder (screw), and the outer periphery of each of the pair of wires is simultaneously coated with the extrusion molding part. A method of manufacturing an electric wire for manufacturing two electric wires having a target outer diameter,
An average value calculation process for measuring the outer diameter of each electric wire and obtaining an average value of these outer diameters;
Extrusion flow increase / decrease processing to increase / decrease the extrusion flow rate of the resin from the extruder and match the average value to the target outer diameter,
When the outer diameter of the electric wire deviates from a predetermined tolerance set with respect to the target outer diameter, a wire that increases or decreases the linear velocity of one electric wire so that the outer diameter of one electric wire falls within the predetermined tolerance Speed increase and decrease processing,
When the extrusion flow rate increase / decrease process and the wire speed increase / decrease process are continued and the outer diameter of each electric wire is within the predetermined tolerance, the wire speed of one of the wires adjusted for the wire speed is changed to the wire speed increase / decrease process. And linear velocity correction processing to increase or decrease in reverse,
And a line speed process for matching the line speed of the one electric wire with the line speed of the other electric wire when the production lengths of the respective electric wires become the same.

According to the method of manufacturing an electric wire of the present invention, two extrusion outer flow increase / decrease processes for increasing / decreasing the extrusion flow rate of the resin in the extruder and a linear velocity increasing / decreasing process for increasing / decreasing the linear velocity of one electric wire are used. Electric wires can be manufactured simultaneously. Thereby, it is possible to eliminate the trouble of adjusting the supply amount of each resin by providing a mechanism for adjusting the supply amount of the resin covering each wire, and the adjustment mechanism itself can be made unnecessary. .
In addition, the wire speed of the two electric wires is adjusted by a line speed correction process that reversely increases / decreases the wire speed of one of the electric wires and the line speed of one electric wire that matches the line speed of the other electric wire. It is possible to match the end timing of manufacturing, eliminate waste of materials due to the difference in end timing, and manufacture two electric wires with high productivity.

It is a schematic block diagram which shows the manufacturing apparatus which can apply the manufacturing method of the electric wire which concerns on this invention. It is sectional drawing orthogonal to the running direction of the electric wire which shows an extrusion molding machine. It is XX sectional drawing of the extrusion molding machine of FIG. It is YY sectional drawing of the extrusion molding machine of FIG. It is a block diagram which shows the outer diameter control system of a control apparatus. (A) to (d) is a diagram for explaining the outer diameter control by the outer diameter control system.

Hereinafter, an example of an embodiment of a manufacturing method of an electric wire concerning the present invention is described with reference to drawings.
As shown in FIG. 1, a manufacturing apparatus 11 that manufactures an electric wire by the electric wire manufacturing method of the present embodiment includes a resin coating portion 13 having an extrusion molding machine 12. In the resin coating portion 13, a preheating device 14 is provided on the upstream side of the extruder 12, and a cooling device 15 is provided on the downstream side.
In order to manufacture the two electric wires C1 and C2 by the manufacturing apparatus 11, the wire 2 is sent from the two wire supply reels 17 to the resin coating portion 13, respectively, and these wires 2 are preheated by the preheating device 14 and extruded. The resin is extrusion coated with the molding machine 12 and cooled with the cooling device 15.

  The wire 2 differs depending on the type of electric wire to be manufactured. For example, when manufacturing an insulated wire, the wire 2 is a conductor, and when manufacturing a coaxial cable, the wire 2 is a shielded core wire in which an insulator and an outer conductor are sequentially provided around a central conductor. In the case where the insulated wire covered with the conductor is covered with a jacket layer made of resin, the wire 2 is an insulated wire.

Then, the two electric wires C1 and C2 covered with the resin by the resin coating portion 13 are respectively taken up by the respective capstans 18 provided for the two electric wires C1 and C2, and are respectively wound on the take-up reels 19. It is wound up.
Further, an outer diameter measuring device 16 is provided between the resin coating portion 13 and the capstan 18, and the outer diameter measuring device 16 measures the outer diameters of the electric wires C1 and C2 that pass therethrough and controls the control device ( (Not shown). As the outer diameter measuring device 16, for example, a laser measuring device that measures the outer diameter of the electric wires C <b> 1 and C <b> 2 in a non-contact manner using laser light is used.

Next, the extrusion machine 12 of the resin coating part 13 which coat | covers resin to the wire 2 is demonstrated.
As shown in FIGS. 2 and 3, the extruder 12 includes an extruder 31 and a crosshead 32. The extruder 31 includes a heating cylinder 33 and a screw 34. The screw 34 is rotated to increase the pressure in the heating cylinder 33, and the resin R is pressurized and melted. To the inside of the crosshead 32.

As shown in FIG. 4, the crosshead 32 includes a die holder 42 in which two extruded portions 40 are provided in parallel. Each extrusion molding part 40 has a holder hole 41 formed in the die holder 42, and these holder holes 41 are formed in parallel to each other. An extruder 31 is installed at an upper position between the holder holes 41.
A cylindrical nipple holder 43 is inserted into the holder hole 41 of each extrusion molding portion 40 from the rear side. These nipple holders 43 are formed with locking step portions 43a in the vicinity of the front ends by making the rear end side larger in diameter, and when the nipple holders 43 are inserted into the holder holes 41 of the die holder 42, The stepped portion 43a is engaged with an engaging projection 42a formed on the inner peripheral surface of the holder hole 41, and axial positioning is performed.

  A resin supply channel 51 formed in a cylindrical shape is formed on the outer periphery of the nipple holder 43 with the nipple holder 43 mounted in the holder hole 41. A branch supply path 52 is formed in the die holder 42. The branch supply path 52 includes a communication path 52a that communicates with the supply path 35 through which the resin R is fed from the extruder 31, and a branch path 52b that bifurcates from the communication path 52a. 52 b communicates with the resin supply flow path 51 of each extrusion molding unit 40.

  As a result, the resin R supplied from the extruder 31 via the supply path 35 is sent to each branch path 52b via the communication path 52a of the branch supply path 52, and the respective extrusion molding units are supplied from these branch paths 52b. It is introduced into 40 resin supply channels 51.

  The nipple holder 43 holds a tapered nipple 61 at its tip. A wire rod introduction hole 61a is formed at the center of the nipple 61, and the wire rod 2 is inserted into the wire rod introduction hole 61a.

  The nipple 61 is formed at its rear end with a locking protrusion 61b that protrudes to the outer peripheral side along the circumferential direction. Further, the nipple holder 43 is formed with an engaging step portion 43b by making the inner diameter at the tip portion small. When the nipple 61 is inserted from the rear end side of the nipple holder 43, the locking protrusion 61 b of the nipple 61 is engaged with the engagement step portion 43 b of the nipple holder 43, and the nipple 61 is pivoted with respect to the nipple holder 43. Positioned in the direction.

Further, a die 62 formed in a mortar shape on the nipple 61 side is held at the tip side of the die holder 42, and a resin introduction gap is formed between the die 62 and the nipple 61. Then, the resin R supplied to the cylindrical resin supply channel 51 is introduced into the resin introduction gap.
The die 62 is formed with a die hole 62a formed in accordance with the outer diameter of the electric wires C1 and C2 to be molded. The die hole 62a is disposed coaxially with the wire rod introduction hole 61a of the nipple 61 in plan view. The wire 2 led out from the wire introduction hole 61a is pushed out from the die hole 62a together with the resin R introduced into the resin introduction gap.

In the manufacturing apparatus 11 including the extrusion molding machine 12 having the above configuration, the molten thermoplastic resin R supplied from the extruder 31 via the supply path 35 to the branch supply path 52 constitutes the branch supply path 52. It branches into each branch path 52b from the communication path 52a, and is sent.
Then, the resin R fed into each of the branch paths 52b is supplied to the cylindrical resin supply flow paths 51 of the respective extrusion molding portions 40, and is further introduced from the resin supply flow paths 51 into the resin introduction gaps. The wire 2 inserted through the wire introduction hole 61 a of the nipple 61 is pushed out from the die hole 62 a of the die 62. Thereby, the wire 2 is arrange | positioned in the center, and the electric wires C1 and C2 by which the outer periphery of the wire 2 was coat | covered with resin R are each extrusion-molded from each extrusion molding part 40. FIG.

Next, the control when manufacturing the two electric wires C1 and C2 by the manufacturing apparatus 11 will be described.
FIG. 5 is a configuration diagram of the outer diameter control system of the control device.
As shown in FIG. 5, the outer diameter measuring device 16 measures the outer diameters D1 and D2 of the respective electric wires C1 and C2, and outputs measurement data of these outer diameters D1 and D2.
The control device sets the outer diameter D1, D2 of the two electric wires C1, C2 to the target outer diameter D, based on the measurement data of the outer diameter measuring device 16, and the wire speed of the wire 2 and the extruder 31 by integral control. The outer diameter is controlled to control the extrusion flow rate of the resin R from.
These measurement data are also output to the outer diameter recorder and recorded by the outer diameter recorder (step S01).

Further, when the measurement data from the outer diameter measuring device 16 is input, the control device performs an average value calculation process for obtaining an average value Dx of the outer diameters D1 and D2 of the electric wires C1 and C2 (step S02).
The control device feeds back to the extruder 31 so that the difference between the obtained average value Dx and the target outer diameter D becomes zero, and controls the rotation of the screw 34 of the extruder 31 to extrude the resin R. Extrusion flow rate increase / decrease processing for adjusting the flow rate is performed (step S04). As a result, the average value Dx of the outer diameters D1, D2 of the electric wires C1, C2 matches the target outer diameter D. In addition, after the extrusion flow rate increase / decrease process, the outer diameter control is returned to the integral control.

  For example, as shown in FIG. 6A, when the average value Dx is shifted to the + (plus) side with respect to the target outer diameter D, the number of rotations of the screw 34 of the extruder 31 per unit time is decreased. Decrease the extrusion flow rate of resin R. As a result, the average value Dx of the outer diameters D1 and D2 of the electric wires C1 and C2 matches the target outer diameter D as shown in FIG.

The extrusion flow rate increase / decrease process is executed in an ON state when the coated electric wire reaches the outer diameter measuring device 16. When the deviation of the average value Dx with respect to the target outer diameter D exceeds a standard value (for example, 5% of the wire diameter), it is fed back to the extruder 31 and the flow rate is changed.
In addition, in the joint part etc. of the wire 2, the outer diameters D1 and D2 of the electric wires C1 and C2 may fluctuate greatly temporarily. If such fluctuations are fed back to the extruder 31, the increase or decrease in the extrusion flow rate of the resin R from the extruder 31 increases, and the outer diameter control becomes unstable.

  For this reason, the control device is provided with a limiter, and even when the deviation of the average value Dx with respect to the target outer diameter D temporarily becomes abnormally large, the outer diameter fluctuation is set to the upper limit value (for example, 10 of the standard value). %) Is preferably performed so that the extrusion flow rate increase / decrease process is performed (step S03).

  In addition, the control device determines that the average value Dx of the outer diameters D1 and D2 of the electric wires C1 and C2 substantially matches the target outer diameter D, but D1 and D2 deviate from a predetermined tolerance centered on the target outer diameter D. If it is, the acceleration / deceleration value ± Dy is fed back to the capstan 18 that picks up the one electric wire C2, and the linear velocity increasing / decreasing process for increasing / decreasing the linear velocity of the electric wire C2 is performed (steps S05, S06). In addition, after the linear speed increase / decrease by the linear speed increase / decrease processing, the outer diameter control is returned to the integral control.

In this linear speed increase / decrease process, when the outer diameter D2 of the electric wire C2 is deviated to the + (plus) side of a predetermined tolerance (for example, 5% of the outer diameter), the acceleration value + Dy corresponding to the deviation amount from the predetermined tolerance When the wire speed is increased and the outer diameter D2 of the electric wire C2 deviates to the − (minus) side of the predetermined tolerance, the wire speed is decreased by the deceleration value −Dy corresponding to the deviation amount from the predetermined tolerance.
The linear velocity increase / decrease process is executed when the deviation of the average value Dx from the target outer diameter D becomes almost zero. Therefore, if the deviation of the average value Dx with respect to the target outer diameter D is not substantially 0 and within ± 0.3 mm, only the extrusion flow rate increasing / decreasing process is executed.

For example, as shown in FIG. 6B, the deviation of the average value Dx with respect to the target outer diameter D is set to 0 by the extrusion flow rate increasing / decreasing process, and the outer diameter D1 of the electric wire C1 is a predetermined tolerance (± 0 in the example of FIG. 6). .025 mm) is deviated to the + (plus) side, and when the outer diameter D2 of the electric wire C2 is deviated to the minus (−) side of the predetermined tolerance, the linear speed increase / decrease process is performed.
Specifically, the capstan 18 is controlled, and the line speed of one electric wire C2 is reduced. Then, the outer diameter D2 of the electric wire C2 increases, and as shown in FIG. 6C, the outer diameter D2 of the electric wire C2 falls within a predetermined tolerance.

  When the linear velocity increase / decrease process is performed in this way and the outer diameter D2 of the electric wire C2 falls within a predetermined tolerance, the linear velocity increase / decrease process is turned off. At this time, since the outer diameter D2 of the electric wire C2 is increased, the average value Dx is shifted to the + (plus) side, and the deviation from the target outer diameter D is not zero. The extrusion flow rate increase / decrease process is executed, the rotation of the screw 34 of the extruder 31 is controlled, and the extrusion flow rate of the resin R is decreased. As a result, the average value Dx of the outer diameters D1, D2 of the electric wires C1, C2 matches the target outer diameter D.

  At this time, D1 and D2 decrease, and as shown in FIG. 6 (d), if the outer diameters D1 and D2 of the respective electric wires C1 and C2 eventually fall within the predetermined tolerance, the extrusion flow rate increase / decrease process and the linear velocity increase / decrease process Exit. If D1 and D2 are not within the predetermined tolerance, the extrusion flow rate increase / decrease process and the wire speed increase / decrease process are repeated until the outer diameters D1 and D2 of the electric wires C1 and C2 finally fall within the predetermined tolerance (± 0.025 mm). Done.

  When the extrusion flow rate increasing / decreasing process and the linear velocity increasing / decreasing process are continued and the outer diameters D1 and D2 of the respective electric wires C1 and C2 are within the predetermined tolerance, the control device outputs a correction signal to the capstan 18 to reduce the linear velocity. A linear speed correction process is performed to increase / decrease the linear speed of the adjusted one electric wire C2 in reverse to the linear speed increase / decrease process.

Specifically, when the wire speed of the electric wire C2 is decreased, the control device outputs a correction signal to the capstan 18 to gradually increase the wire speed of the electric wire C2. Conversely, when the wire speed of the electric wire C2 is increased, the wire speed of the electric wire C2 is gradually decreased.
The increase or decrease of the linear velocity in this linear velocity correction process is limited so that the outer diameters D1 and D2 of the electric wires C1 and C2 do not deviate from the predetermined tolerance, and the amount of change in the linear velocity is the set linear velocity (C1 Speed) within ± several percent (eg ± 2.5%).

When the production lengths of the electric wires C1 and C2 are the same, at that time, the control device controls the capstan 18 so that the linear velocity of one electric wire C2 matches the linear velocity of the other electric wire C1. Process.
Thereby, the production of the set-length electric wires C1 and C2 is completed almost simultaneously.

  Even if the outer diameters D1 and D2 of the electric wires C1 and C2 deviate from the predetermined tolerance (± 0.025 mm) again, the extrusion flow rate increase / decrease process, the linear speed increase / decrease process, the linear speed correction process, and the equal linear speed process are executed. The outer diameters D1 and D2 are accommodated within a predetermined tolerance (± 0.025 mm), and the wire speeds and manufacturing lengths of the electric wires C1 and C2 are matched.

According to the electric wire manufacturing method of the above embodiment, the target outer diameter D and the extrusion flow increase / decrease process for increasing / decreasing the extrusion flow rate of the resin R in the extruder 31 and the linear velocity increasing / decreasing process for increasing / decreasing the linear velocity of one electric wire C2 are performed. The two electric wires C1 and C2 thus manufactured can be manufactured at the same time. Thereby, a flow rate adjustment mechanism can be made unnecessary.
In addition, two lines are provided by a line speed correction process for conversely increasing / decreasing the line speed of one electric wire C2 whose line speed is adjusted and an equal line speed process for matching the line speed of one electric wire C2 with the line speed of the other electric wire C1. The end timings of the production of the electric wires C1 and C2 can be matched, and the two wires C1 and C2 can be manufactured and productivity can be improved without inconvenience such as waste of materials due to the end timings being different. .
Further, the control of the wire speed is performed only when the outer diameters D1 and D2 of the electric wires C1 and C2 deviate from the predetermined tolerance, and the wire speed of the other electric wire C1 is fixed and performed only on the one electric wire C2 side. It is possible to simplify the system by simplifying the control.

2: wire rod, 11: manufacturing apparatus, 12: extrusion molding machine, 13: resin coating part, 31: extruder, 40: extrusion molding part, C1, C2: electric wire, D: target outer diameter, D1, D2: outer diameter , Dx: average value, R: resin

Claims (1)

A method of manufacturing an electric wire, in which a resin is fed into a pair of extrusion-molded portions by an extruder, and the outer periphery of each of a pair of wires is simultaneously coated with the resin by the extrusion-molded portion to produce two wires having a target outer diameter. ,
An average value calculation process for measuring the outer diameter of each electric wire and obtaining an average value of these outer diameters;
Extrusion flow increase / decrease processing to increase / decrease the extrusion flow rate of the resin from the extruder and match the average value to the target outer diameter,
When the outer diameter of the electric wire is out of the predetermined tolerance set with respect to the target outer diameter, the linear velocity of the one electric wire is increased or decreased so that the outer diameter of the one electric wire falls within the predetermined tolerance. Linear velocity increase / decrease processing;
When the extrusion flow rate increasing / decreasing process and the linear velocity increasing / decreasing process are continued and the outer diameter of each electric wire is within the predetermined tolerance, the linear velocity of the one electric wire adjusted for the linear velocity is changed to the linear velocity increasing / decreasing process. Linear velocity correction processing to increase or decrease in reverse to the time,
Equal wire speed processing to match the wire speed of the one electric wire with the wire speed of the other electric wire when the production length of each electric wire becomes the same,
The manufacturing method of the electric wire characterized by including.

Images