JP3125958B2 - Prevention method of seizure of color change valve in wire coating extruder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method of supplying a synthetic resin which is colored differently in accordance with a colored synthetic resin supplied from a main extruder when coating a synthetic resin on a conductor, The present invention relates to a switching device for interrupting a supply path of a colored coating synthetic resin when supplying a coating synthetic resin having a different color in place of a coloring synthetic resin supplied from a main extruder. The present invention relates to a method for preventing seizure of a color change valve in an electric wire covering extruder for preventing seizure of a color change valve for switching a color synthetic resin supplied in accordance with a synthetic resin supplied to a wire.

[0002]

2. Description of the Related Art In general, electric wires and cables have a structure in which a conductor is covered with a synthetic resin insulator. This electric wire / cable improves electrical stability, imparts flexibility,
In order to improve the space factor (multiple cores are accommodated in a small outer diameter), most of them, other than single-core cables, are stranded wires obtained by twisting a group of wire cores by various methods. In the case of this stranded cable, a plurality of electric wires and cables are stranded and an outermost sheath made of synthetic resin (for example, polyvinyl chloride resin) is coated on the outside. When coating this sheath, a main resin extruder 1000 as shown in FIG. 4 is generally used. That is, the resin extruder 1000 includes the crosshead 1
The die 1100 is attached to the tip of the crosshead 1700. This die 1
100 is a flange 112 at the rear end of the die body 1110.
0 is provided. The die body 1110 is
The die body 1110 is formed in a cylindrical shape, and a tapered portion 1130 is formed on the inner surface of the die body 1110 by providing a shape retaining portion 1150 at a predetermined distance from the tip end opening 1140. The tapered portion 1130 in the die body 1110 has a die body 11
10, a predetermined distance from the inner surface of the cylindrical nipple 14
00 is fitted. The die body 1110 and the nipple 1400 are arranged concentrically.

[0003] A die holder 1200 is engaged with a flange 1120 at the rear end of the die body 1110. An adjustment bolt 1300 is attached to the die holder 1200, and the adjustment bolt 1300 is for adjusting the deflection of the die body 1110. Also,
Nipple 14 fitted on the inner surface of die body 1110
00 is fixed to the nipple holder 1500,
The nipple holder 1500 is fixed to the sleeve 1600. The coating resin 2200 is sequentially fed under pressure from the adapter 1900 to the extrusion portion 1800 formed between the inner surface of the die body 1110 and the nipple 1400 through the conduit 2100 via the switching cock 2000. I have. The pressure feeding of the coating resin 2200
This is done by rotating the screw. A resin colored in a predetermined color in the form of pellets is supplied to the screw from a hopper (not shown), and heated and melted and extruded in the screw. A plurality of hoppers are provided according to the number of ground colors (for example, gray, white, etc.) of the coating resin, and can be switched and supplied according to the selection of the ground color of the coating resin. Therefore, the coating resin 2200 sequentially pressure-fed from the adapter unit 1900 is applied to the surface of the wire 3000 traveling substantially at the center of the nipple 1400 and the shape retaining unit 1 of the die 1100.
Coat at 150. The wire 30 coated with the coating resin 2200 in the shape retaining portion 1150 of the die 1100
00, after passing through the opening 1140 of the die 1100, the coating resin 2200 is cooled by contact with air,
Is cured and preserved.

[0004] When the color of the coating resin 2200 coated on the surface of the wire 3000 is changed, the crosshead 17 is temporarily changed.
The supply of the coating resin 2200 to the resin extruder 00 is stopped, the hopper containing the coloring material is switched to the designated color, and the resin is newly supplied to the resin extruder 1000. Then, after changing the colored resin, the old colored resin before the color change is switched to the switching cock 2.
When the operator discharges from a discharge port (not shown) of No. 000, the worker stays on the side and visually checks until a new color of the coating resin is discharged, and determines that the completely new color of the coating resin is output. Then, the extrusion coating on the wire 3000 is restarted. The switching cock 2000 has a coating resin 220
0 is supplied to the cross head 1700 to discharge a part of the coating resin of the new color connected to the old color coating resin 2200 before the color is changed. Also, this switching cock 2000 uses the coating resin 2200 to move the crosshead 17.
A heater is provided inside to smoothly supply the coating resin 200 to 00, and the coating resin 2200 is heated to an appropriate temperature. The switching of the switching cock 2000 is performed by using a spanner 250.
0 from the resin extruder 1000 to the crosshead 170
The supply path to 0 is changed to a discharge path from the resin extruder 1000 to the outside. When switching the switching cock 2000, before switching the switching cock 2000, the production line is stopped, the hopper containing the coloring material is switched, and the colored coating resin supplied to the resin extruder 1000 is changed. Exchange. Then, switch the switching cock 2000,
The supply path from the resin extruder 1000 to the crosshead 1700 is changed to a discharge path from the resin extruder 1000 to the outside. By the switching of the switching cock 2000, the coating resin extruded by the screw of the resin extruder 1000 is discharged from the outlet of the switching cock 2000. The resin discharged first from the outlet of the switching cock 2000 is the old-colored coating resin before the color is changed, and after a while, the resin in which the old-colored coating resin and the new-colored coating resin are mixed is discharged. After a while, only the coating resin of the new color is discharged. When the worker confirms that only the coating resin of the new color has been discharged, the worker switches the switching cock 2000 using the spanner 2500, and the resin extruder is discharged from the resin extruder 1000 to the outside through the discharge path. Change the supply path from 1000 to the crosshead 1700. By the switching of the switching cock 2000, the coating resin of the new color is supplied to the crosshead 1700.
The production line is restarted at the same time as the switching cock 2000 is switched. In this way, the switching from the old-colored coating resin to the new-colored coating resin is performed.

By the way, such electric wires and cables are
They are used differently depending on the purpose of use or the type of place of use. In other words, when connecting one end of an electric wire or cable to a specific device, and connecting the other end of the electric wire or cable connected to this device to another device or power supply, insulate it so that the connection of the wire to be connected is correct. The body is colored in stripes. In the case of electric wires and cables, it is particularly important that the insulator is colored, since there is a danger of line-to-line short-circuiting if the connection is incorrectly made at the terminals or connection parts.

[0007] Stripe coloring of the insulator is performed by using a sub-extruder 5000 as shown in FIG. 5 and using a coating resin supplied from a main resin extruder 1000 as a ground color, and coloring the striped shape there. It is formed by coating with a coating resin. The coating of the colored coating resin is performed by using a resin extruder 100.
At the same time as extruding and coating the coating resin from 0, the coating resin is extruded and coated from the sub-extruder 5000 so that the colored coating resin is vertically applied in a stripe shape. The stripes formed on the insulators and sheaths of the electric wires and cables are made of a resin colored differently from the ground color (eg, gray, white, etc.) of the insulators, for example, red, yellow, or the like. The colors of this stripe vary widely. Therefore, the sub extruder 5000 is also used as the main resin extruder 1000.
Similarly, a resin colored in a predetermined color in the form of pellets is supplied from a hopper into a screw, and is heated and melted and extruded in the screw. A plurality of hoppers containing colored resin are provided according to the number of stripe colors (for example, red, yellow, black, etc.) formed on the insulator of the electric wire or the sheath of the cable. It can be switched and supplied according to the color selection. Therefore, when changing the color of the stripe formed on the surface of the wire 3000, the supply of the stripe-forming resin to the crosshead 1700 is temporarily stopped, and the hopper for supplying the coloring material to the sub-extruder 5000 is switched. In the sub-extruder 5000, the colored coating resin for the stripe supplied from the hopper is extruded into the switching cock 6000 by the action of a screw. In changing the color of the coating resin for the stripe, after changing the color resin by switching the hopper containing the coloring material, the old coating resin before changing the color is discharged, and the coating resin of the new color is discharged. Until the worker stays on the side and visually checks, and when it is judged that the coating resin of a completely new color has been output, the extrusion coating on the wire 3000 is restarted.

The switching cock 6000 stops the supply of the stripe coating resin to the crosshead 1700 and discharges a part of the new color stripe coating resin connected to the old color stripe coating resin before changing colors to the outside. belongs to. The switching cock 6000 is provided with the coating resin 2.
In order to smoothly supply 200 to the crosshead 1700, a heater is provided inside, and the coating resin 220 is provided.
0 is appropriately heated to a temperature. This switching cock 6000
Of the sub-extruder 500 using a spanner 2500
The supply path from 0 to the crosshead 1700 is changed to a discharge path from the sub-extruder 5000 to the outside. When switching the switching cock 6000, the switching cock 60
Before switching 00, the production line is stopped, the hopper containing the coloring material is switched, and the colored stripe coating resin supplied to the sub-extruder 5000 is replaced.
Thereafter, the switching cock 6000 is switched, and the sub extruder 50
The supply path from 00 to the crosshead 1700 is changed to a discharge path from the sub-extruder 5000 to the outside. By switching the switching cock 6000, the sub-extruder 5000
Is discharged from the outlet of the switching cock 6000.
The resin first discharged from the discharge port of the switching cock 6000 is an old-colored stripe coating resin before changing colors.
After a while, a resin in which the old color stripe coating resin and the new color stripe coating resin are mixed is discharged, and after a while, only the new color stripe coating resin is discharged. When the worker confirms that only the new color stripe coating resin has been discharged, the worker uses the spanner 2500 to switch the switching cock 600.
0, and the supply path from the sub-extruder 5000 to the crosshead 1700 is changed from the discharge path from the sub-extruder 5000 to the outside. By switching the switching cock 6000, the coating resin for the stripe of the new color is changed to the crosshead 1.
700. The production line is restarted at the same time as the switching cock 6000 is switched. In this way, the switching from the old-colored stripe coating resin to the new-color stripe coating resin is performed.

In the case where wires and cables are manufactured by forming stripes on the surface of the resin that covers the wire 3000, when the formation of stripes is stopped by coating the wire 3000 with plain resin, a spanner is used. The switching cock 6000 is switched using the 2500 and the supply path from the sub-extruder 5000 to the crosshead 1700 is shifted so that the coating resin for the stripe is not supplied from the sub-extruder 5000 to the crosshead 1700. To stop.

Thereafter, when a stripe is formed again on the surface of the resin to be coated on the wire 3000, the wrench 250 is used.
0, the switching cock 6000 is switched, and the sub-extruder 5
000 and the supply path from the sub-extruder 5000 to the crosshead 1700,
Activate the screw of the sub-extruder 5000.

[0010]

However, in the conventional method of coating the surface of a wire with a coating resin using a wire coating extruder, a wire / cable is manufactured by forming a stripe on the surface of the resin coated on the wire 3000. When the formation of stripes is stopped in order to manufacture an electric wire or cable in which a wire 3000 is coated with a plain resin, the switching cock 6000 is switched by the spanner 2500 and the sub-extruder 5000 is connected to the crosshead 1700. The supply path is changed to a discharge path from the sub-extruder 5000 to the outside, and the screw of the sub-extruder 5000 is stopped.
Thereafter, when forming a stripe on the surface of the resin to be coated on the wire 3000 again, the switching cock 6000 is switched by the spanner 2500, and the discharge path from the sub-extruder 5000 to the outside is transferred from the sub-extruder 5000 to the crosshead 1700. And the screw of the sub-extruder 5000 is operated. When the stripe is not formed on the surface of the resin that covers the wire 3000 in this manner, the switching cock 6000 is switched by the spanner 2500 to stop the stripping coating resin at the switching cock 6000. There is a problem that the coating resin for the stripe in the portion is burned and the switching cock 6000 does not rotate.

According to the present invention, the switching cock for switching the stripe coating resin supplied from the sub-extruder in accordance with the synthetic resin supplied to the crosshead from the main extruder is switched to switch the resin from the sub-extruder. It is an object of the present invention to provide a method for preventing color change valve seizure in an electric wire covering extruder that can prevent seizure of a switching cock even when extrusion is stopped for a long time.

[0012]

In order to achieve the above object, a method for preventing seizure of a color change valve in an electric wire covering extruder according to the present invention is described in which a running insulated electric wire is covered by a main extruder from a main extruder. While supplying the resin and extruding a coating resin of a different color from the coating resin for the ground color from the sub-extruder to form a stripe and cover the sheath, based on a color change command input by the operation panel, The sub-extruder is stopped and the switching cock is rotated by the driving means to close the supply path of the stripe coating resin to the crosshead, and the supply of the stripe coating resin to the sub-extruder is stopped. After the extruder is stopped, the switching cock of the coating resin for the stripe is reciprocated by a predetermined angle every predetermined time by the driving means.

[0013]

After stopping the colored striping coating resin supplied from the sub-extruder in accordance with the ground color coating resin supplied from the main extruder based on a command from the operation panel, every predetermined time elapses The switching cock is rotated back and forth by a predetermined angle by the driving means, so that the coating resin for the stripe supplied from the sub-extruder is intermittently connected to the synthetic resin supplied to the crosshead from the main extruder. Even if the switching cock for switching is switched and the resin extrusion from the sub-extruder is stopped for a long time, seizure of the switching cock can be prevented.

[0014]

Embodiments of the present invention will be described below. FIG. 1 shows an embodiment of a method for preventing seizure of a color changing valve in an electric wire covering extruder according to the present invention.

In the figure, 1 is a hopper and 2 is a main resin extruder. A plurality of hoppers 1 are provided, each of which stores a pellet-shaped resin colored in a predetermined color. That is, the hopper 1
Plural resins are provided to the main resin extruder 2 by switching according to the selection of the ground color of the coating resin, and a plurality of the resins are provided according to the number of ground colors (eg, gray, white, etc.) of the coating resin. It has become. In addition, the main resin extruder 2 receives a supply of pellet-shaped resin from one of the plurality of hoppers 1, heats and melts the resin in a screw cylinder, and extrudes it while pressing with a screw. The main resin extruder 2 has a crosshead. The crosshead covers the wire 3000 with the coating resin 6 heated and melted in the screw cylinder of the main resin extruder 2.

From the screw cylinder of the main resin extruder 2, the switching cock 2
The coating resin 6 is sequentially fed under pressure through the pipe through the pipe 0. The switching cock 20 includes a rod-shaped switching valve having a passage formed therein, and is opened and closed by rotating the switching valve by a predetermined angle. The pressure feeding of the coating resin 6 is performed by rotating a screw in a screw cylinder. The screw is supplied with a resin colored in a predetermined color in the form of a pellet from a hopper 1 (not shown), and heated and melted and extruded in the screw. The hopper 1 is provided with a ground color (for example, gray,
(Eg, white), and can be switched and supplied according to the selection of the ground color of the coating resin.

Reference numeral 22 denotes a driving means for rotating the switching valve of the switching cock 20 by a predetermined angle. In this embodiment, a pneumatic device which performs a oscillating motion is constituted by an oscillating cylinder. That is, the oscillating cylinder in the present embodiment, for example, so that linear motion can be changed to rotational motion, for example,
Rack pinion is built in. Reference numeral 23 denotes an electromagnetic valve for controlling the driving of the driving means 22. That is, the solenoid valve 23 controls the flow of air supplied to the swing cylinder.

An operation panel 24 controls the electromagnetic valve 23, inputs a color change command, performs color change of the hopper 1 in response to the color change command input, and instructs a line stop / start. It is a control device.

Reference numeral 30 denotes a hopper, and 31 denotes a sub resin extruder. A plurality of the hoppers 30 are provided, each of which stores a pellet-shaped resin colored in a predetermined color. That is, a plurality of hoppers 30 are provided in accordance with the number of colors (for example, red, yellow, etc.) of the coating resin for the stripe, and the hopper 30 is switched according to the selection of the ground color of the coating resin to switch the pellet-shaped resin to It can be supplied to the resin extruder 31. Further, the sub-resin extruder 31 receives a supply of pellet-shaped resin from one of the plurality of hoppers 30, heats and melts the resin in a screw cylinder, and extrudes the resin while pressing with a screw. The sub resin extruder 31 has a crosshead 50. The crosshead 50 covers the wire 3000 with the coating resin 6 heated and melted in the screw cylinder of the main resin extruder 2, and at the same time, coats the striped coating resin 40 heated and melted in the screw cylinder of the sub resin extruder 31. Is extruded thinly so as to be coated in a stripe shape, and as shown in FIG. 2, the coating material 6 is coated on the wire 3000 together with the coating resin 6 in a stripe shape.

Reference numeral 32 denotes a switching cock, which is a sub resin extruder 31.
This is a valve that controls the intermittent supply of the coating resin for stripes to the crosshead 50 from the. Therefore, switching cock 3
2 has a built-in heater and is always heated to a constant temperature so that it can be supplied immediately when a stripe coating resin supply command is issued. A switching valve 33 is rotatably fitted to the switching cock 32, and the switching valve 33 is provided with an overflow hole 34. Therefore, the switching cock 32 is connected to the switching valve 3
3 is rotated by a predetermined angle, and the strip coating resin 40 is discharged from the supply path for supplying the strip coating resin 40 to the crosshead 50 through the sub resin extruder 31 to the overflow hole 34 through the sub resin extruder 31. Or the crosshead 5 passes through the sub-resin extruder 31 from the discharge path through which the stripping resin 40 is discharged into the overflow hole 34 through the sub-resin extruder 31.
For example, the supply path for supplying the stripe coating resin 40 to 0 is changed.

The switching valve 33 of the switching cock 32 is rotated by a predetermined angle, and passes through the
If the supply path for supplying the stripe coating resin 40 to the discharge path for discharging the stripe coating resin 40 to the overflow hole 34 through the sub-resin extruder 31 is changed, the stripe from the sub-resin extruder 31 to the crosshead 50 is changed. The supply of the coating resin 40 is stopped, and in the sub-resin extruder 31, the colored stripe coating resin 40 supplied from the hopper 30 is pushed out to the switching cock 32 by the action of the screw. Therefore, the coating resin for stripes 40 of the old color is overflowed by the action of the screw for a certain period of time (color change time) to be replaced with the coating resin for stripes 40 of the new color, that is, for a certain period of time until the color change is completed. 40 overflows.

Reference numeral 35 denotes a driving means for rotating the switching valve 33 of the switching cock 32 by a predetermined angle. In this embodiment, a pneumatic device which performs a oscillating motion is constituted by an oscillating cylinder. Means may be used. That is, the swing cylinder according to the present embodiment is configured to include, for example, a rack and pinion so that the linear motion can be changed to the rotary motion. Numeral 36 denotes an electromagnetic valve for controlling the driving of the driving means 35. That is, the solenoid valve 36 controls the flow of air supplied to the swing cylinder.

Next, the operation of this embodiment will be described.
When changing the color of the coating resin 6 coated on the surface of the wire 3000, a color change command is input to the operation panel 24. By this color change command input, the operation panel 24 causes the hopper 1 and the solenoid valve 2
3, and outputs a line stop signal for stopping the production line to the line control device. The production line is stopped by the line stop signal. In addition, the hopper 1 containing the resin in the form of pellets with the coloring specified based on the color change operation signal moves or opens the inlet of the main resin extruder 2, and the pellets are transferred to the main resin extruder 2. The supply of resin in a shape is started. At the same time, the electromagnetic valve 23 operates based on the color change operation signal, drives the drive means 22, rotates the switching valve of the switching cock 20 by a predetermined angle, and supplies the switching resin from the main resin extruder 2 to the crosshead. The path is changed to a discharge path from the main resin extruder 2 to the outside. Then, the supply of the coating resin 6 from the main resin extruder 2 to the crosshead is stopped, and in the main resin extruder 2, the colored coating resin 6 supplied from the hopper 1 is supplied.
Is pushed out to the discharge port of the switching cock 20 by the action of the screw. Therefore, the resin of the old color overflows for a certain period of time (color change time) by the action of the screw, and overflows for a certain period of time until the resin of the new color is changed, that is, until the color change is completed.

In order to change the color of the stripe coating resin 40 in the coating resin 6 coated on the surface of the wire 3000, a color change command is input to the operation panel 24. In response to the input of the color change command, the operation panel 24 outputs a color change operation signal to the hopper 30 and the electromagnetic valve 36 and outputs a line stop signal for stopping the production line to a line control device (not shown). The production line is stopped by the line stop signal. Further, the hopper 30 containing the pellet-shaped striped resin coated with the coloring specified based on the color change operation signal moves to the input port of the sub-resin extruder 31, and The supply of the pellet-shaped stripe coating resin is started. At the same time,
Based on the color change operation signal, the solenoid valve 36 is operated, the driving means 35 is driven, the switching valve 33 of the switching cock 32 is rotated by a predetermined angle, and the sub resin extruder 31
Is changed to a discharge path from the sub-resin extruder 31 to the overflow hole 34. Then, the supply of the stripe coating resin 40 from the sub-resin extruder 31 to the crosshead 50 stops, and in the sub-resin extruder 31,
The colored striping coating resin 40 supplied from the hopper 30 is pushed out to the switching cock 32 by the action of a screw. Therefore, the coating resin for the old color stripe is caused to overflow for a predetermined time (color change time) by the action of the screw, and is allowed to overflow for a predetermined time until the coating resin for the new color is changed, that is, until the color change is completed.

FIG. 3 is a flowchart showing this control. In FIG. 3, when the production line starts, in step 300, necessary data such as a color change condition is read. Next, in step 301, it is determined whether or not there is an instruction that a stripe exists. This step 3
At 01, it waits until an instruction indicating that a stripe exists is issued.
In step 301, when an instruction for the presence of a stripe is issued, in step 302, the sub-resin extruder 31 is drive-controlled. When the sub-resin extruder 31 is driven, it is determined in step 303 whether or not the striping has been completed. If it is determined in step 303 that the stripes have been added, step 304
, It is determined whether or not there is a color change instruction, that is, whether or not to change the color of the stripe currently attached. If there is a color change instruction in step 304,
Moving to step 305, the production line is stopped.

If it is determined in step 303 that the stripes have not been added, step 306 is executed.
, It is determined whether or not there is a color change instruction, that is, whether or not to change the color of the stripe currently attached. If it is determined in step 306 that there is no color change instruction, the process returns to step 303. If it is determined in step 304 that there is a color change instruction, the process proceeds to step 305 to stop the production line.

When the production line is stopped in step 305, in step 307, the hopper 30 storing the stripe coating resin of the color specified based on the color change instruction is moved or opened, and the color change condition (what The color change time (a fixed time until the color change is completed) is calculated based on the number of colors changed from the color). These color change times are empirical values, approximately 4 when changing from white to pink.
0 seconds, and about 55 seconds when changing from pink to black can also be set. In step 307, the color change time is calculated based on the color change condition, and at the same time, the solenoid valve 36 is opened to drive the drive means 35 to thereby control the overflow hole 34
To the position.

Next, in step 308, it is determined whether or not the color change time calculated in step 307 has elapsed.
If it is determined in step 308 that the color change time has elapsed, in step 309, the solenoid valve 36 is operated to drive the driving means 35, and the switching valve 33 of the switching cock 32 is rotated by a predetermined angle, so that the sub resin extruder 31 The discharge path to the overflow hole 34 is changed from the sub resin extruder 31 to the supply path to the crosshead 50. Then start the line. Further, it is determined in step 310 whether or not the production line is stopped. If the production line is stopped, the flow is terminated. If it is determined that the production line is not stopped, the process returns to step 303.

If it is determined in step 304 that there is no color change instruction, the process proceeds to step 311 and the switching cock 32 is closed. That is, the solenoid valve 36 is operated to drive the driving means 35, and the switching valve 33 of the switching cock 32 is rotated by a predetermined angle, so that the sub resin extruder 31
Block the supply route to When the switching cock 32 is closed in step 311, it is determined in step 312 whether or not there is an instruction to form a stripe on the wire / cable to be manufactured. If it is determined in step 312 that an instruction to form a stripe has been issued, the process returns to step 302. If it is determined in step 312 that there is no instruction to perform stripe formation, in step 313, after waiting for a predetermined time, in step 314, the switching valve 33 of the switching cock 32 is moved from the sub-resin extruder 31 to the cross position. The angle of rotation is such that the supply path to the head 50 does not open. Reciprocating movement of the switching valve 33 of the switching cock 32 is more effective. Then, returning to step 312, the switching valve 33 of the switching cock 32 is set at an angle within a range that the supply path from the sub-resin extruder 31 to the crosshead 50 is not opened at regular intervals until an instruction to form a stripe is issued. Rotate.

Therefore, according to the present embodiment, the crosshead 5 is moved from the sub-resin extruder 31 through the switching cock 32.
When the coating resin for stripes is not supplied to 0, it is possible to prevent the coating resin for stripes from burning in the switching cock 32 heated to a certain temperature.

[0031]

According to the present invention, a ground extruder is supplied to a traveling insulated wire from a main extruder and a colored extruded resin different from the ground extruder is extruded from a sub-extruder. While forming the stripe and covering the sheath, the sub-extruder is stopped and the switching cock is rotated by the driving means based on the color change command input by the operation panel, so that the crossing of the coating resin for the stripe is performed. The supply path to the head is closed, the supply of the coating resin for stripes to the sub-extruder is stopped, and after the sub-extruder is stopped, the switching cock of the coating resin for stripes is turned on by the driving means every predetermined time. The reciprocating angle is set to a preset value, so that the sub-extruder feeds the synthetic resin supplied to the crosshead from the sub-extruder. Can be stopped for a long time the resin extruded from the sub-resin extruder by switching the switch cock for performing intermittent-switching of Ripe for coating resin to prevent burn-in of switching cock.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an entire configuration showing an embodiment of a color change control method in an electric wire covering extruder according to the present invention.

FIG. 2 is a sectional view of electric wires and cables discharged from a crosshead in the embodiment shown in FIG.

FIG. 3 is a control flowchart of the embodiment shown in FIG.

FIG. 4 is a plan view showing the overall configuration of a conventional wire coating extruder for coating a resin on a wire or cable.

FIG. 5 is an overall schematic view of a conventional wire coating extruder for extruding and coating a striping resin at the same time as coating a resin on an electric wire or cable.

[Explanation of symbols]

1,30 ………………………… hopper 2 …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………… …………… Crosshead 6 ……………………………… Coating resin 20, 32 ……………………………………… Switching cock 22, 35 ...... Driving means 23, 36 ...... Solenoid valves 24, 37 ...... …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………… Valve 34 ...... Overflow hole 40 ...... Overlap hole 40 ...... Striping coating resin 3000 ...... ………………………wire

Continuation of the front page (56) References JP-A-1-307113 (JP, A) JP-A-64-84523 (JP, A) JP-A-60-83821 (JP, A) JP-A-62-163208 (JP, A) , A)

Claims (1)

(57) [Claims] 1. A coating resin for ground color is supplied to a traveling insulated wire from a main extruder, and a coating resin different in color from the coating resin for ground color is extruded from a sub-extruder to form a stripe. During coating, the sub extruder is stopped based on a color change command input from the operation panel, and the switching cock is rotated by the driving means to supply the stripe coating resin to the crosshead. After closing the supply of the coating resin for the stripe to the sub-extruder and stopping the sub-extruder, the switching cock of the coating resin for the stripe by the driving unit is reciprocated at a predetermined angle every predetermined time. A method for preventing seizure of a color changing valve in an electric wire coating extruder configured to rotate.