JPH0922627A - Method for controlling wire speed during extrusion covering process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for ensuring rapid control of the tension of wire, allowing replacement of winding bobbins to be performed safely and enabling the speed of the wire to be increased easily. SOLUTION: A process for extrusion covering includes forming a covered wire 1A by extrusion covering using an extruder 3 a wire 1 fed out of a feeder 2, and winding the covered wire 1A on a winding device 7 located downstream of a taking device 5, while taking the wire by means of the taking device 5. A wire storage device 8 is provided upstream of the winding device 7 to store the wire during replacement of winding bobbins, and a tension detection means 9 is provided between the feeder 2 and the extruder 3 to control the taking speed of the taking device 5, based on the feed rate of the feeder 2 and on a tension value detected by the tension detection means 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear velocity control method in an extrusion coating process.

[0002]

2. Description of the Related Art FIG. 2 shows a conventional apparatus used in an extrusion coating process for forming an extrusion coating on a wire 1, such as a high-foam coaxial cable manufacturing line.
As for the conventional process, the wire 1 sent out from the delivery device 2 at a constant speed is covered with a coating in the extruder 3 and then passed through the cooling water tank 4 to be taken up by, for example, a belt wrap type take-up device 5. While being wound, the winding device 7 located downstream
It is wound up.

The take-up device 5 is provided with a dancer roller 6, and the tension fluctuations occurring in the line are caused by the dancer roller 6.
It is configured to be absorbed by raising and lowering. The fluctuation of tension in the line impairs the uniformity of the coating thickness and the like, which is extremely undesirable in quality control of the product.

[0004]

When the take-up bobbin of the take-up device is replaced, the product cannot be taken up during this period, so that it is difficult to process the wire that flows while being covered, and the floor of the workplace is difficult to handle. We had to hurry to replace the winding bobbin while putting together the product lines that accumulated in such as by two or more human powers. Also, the tension in the line is kept at a predetermined value by a dancer roller device provided with a predetermined load on the take-up device. However, this dancer roller system has a slow response and cannot perform constant tension adjustment sufficiently. There was an inconvenience.

[0005]

The present invention has been made to solve the above-mentioned problems, and the solution means according to the invention of claim 1 is to extrude a wire sent from a feeding device in an extruder. In the extrusion coating process, in which the coated wire is formed by applying a coating and then the coated wire is taken up by a take-up device and wound on a winding device downstream thereof, a wire-storing device is provided on the upstream side of the winding device to wind the wire. The wire is stored here when the bobbin is replaced, and tension detecting means is provided between the feeding device and the extruder, and the tension is detected by the feeding speed of the feeding device and the tension value detected by the tension detecting means. It is a linear velocity control method in an extrusion coating process, characterized in that a take-up speed of a take-up device is controlled.

[0006]

In the wire-storing device, the extrusion covered wire is stored in the wire-storing device for a long time, so that the winding bobbin can be easily replaced, and the tension fluctuation signal from the tension detecting means is sent by the sending device at that time. By the signal of the result of comparing
The take-up device is rotationally driven so as to eliminate the tension fluctuation.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENT An example of an apparatus for carrying out the method of the present invention will be described with reference to FIG. The strands 1 are sent from the left side to the right side of the figure, and the description will be made sequentially from the device upstream of the flow of the strands 1.

The filament 1 is delivered by a caterpillar type delivery device 2, for example. The drive device 21 is driven so that the delivery device 2 delivers the strand 1 at a constant speed. An extruder 3 is provided downstream thereof, and the extrusion coated wire 1A is formed through the extruder 3. In the present invention, a tension pickup, that is, a tension detecting means, of a type in which a load cell is combined with a roller that is in pressure contact with the traveling line of the wire between the feeding device 2 and the extruder 3 to detect the tension fluctuation of the wire. 9 is provided.

A cooling water tank 4 is installed downstream of the extruder 3, and a belt wrap type take-up device 5, which is rotationally driven by a drive motor 51, is provided downstream of the cooling water tank 4. A storage device 8 is provided downstream of the take-up device 5, and a take-up device 7 is provided at the final position as in the conventional case.

The storage line device 8 is of a type in which the line is stored by winding the line between a number of sheaves several times, and the stored dose is increased by increasing the spacing between the sheaves. Is. This sheave interval is set so as to be constant according to the tension of the covered wire to be wound, and when the tension on the winding side becomes zero, such as when replacing the winding bobbin, the spacing increases and automatically The line will start at.

A signal line extends from the tension detecting means 9 and the delivery drive motor 21, and a control circuit is provided for controlling the rotation speed of the take-up drive motor 51 in accordance with the result of comparison of signals from the two.

This control circuit is simply described, for example, when an increase in tension is detected by the tension detecting means 9,
The control circuit controls the drive motor 51 so that the take-up speed of the take-up device 5 becomes slower than the take-out speed of the take-out drive motor 21 to lower the tension.

[0013]

According to the present invention, since the storage line device is provided, there is an advantage that the time for changing the take-up bobbin can be increased, the change of the take-up bobbin is easy, and it is safe because it does not depend on human power. The tension response signal from the tension detecting means is compared with the current delivery speed of the delivery device, and the control response is extremely fast because the take-up speed of the take-up device is rapidly controlled so as to eliminate the tension variation. There is an effect.

[Brief description of drawings]

FIG. 1 is a simplified side view showing an example of an apparatus for carrying out the present invention.

FIG. 2 is a simplified side view showing an example of a conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Elementary wire 1A Coated wire 2 Feeding device 21 Feeding drive motor 3 Extruder 4 Cooling water tank 5 Pulling device 51 Pulling drive motor 7 Winding device 8 Storage wire device 9 Tension detecting means

Claims (1)

[Claims] 1. A wire (1) sent out from a delivery device (2) is extrusion coated in an extruder (3) to form a coated wire (1A), and the wire (1A) is then taken out by a take-up device (1A). Winding device (7) downstream of the take-up device (5)
The winding device (7) in the extrusion coating step of winding into
A wire storage device (8) is provided on the upstream side of the wire so that the wire is stored here when the winding bobbin is replaced, and a tension detecting means (9) is provided between the delivery device (2) and the extruder (3). And an extraction speed of the extraction device (2) and a tension value detected by the tension detection means (9) to control the withdrawal speed of the withdrawal device (5). Linear velocity control method in coating process.