JPH03212108A - Method of stripping extra fine metal tube - Google Patents

Abstract

PURPOSE:To prevent tensile tearing due to partial bending by cutting an extra fine metal tube through slits directed in two directions opposite to each other out of four longitudinal slits and by causing the metal tube to spread round the remaining unseparated bidirectional slit to form flat, almost W-shaped cross sections and by winding the metal tube. CONSTITUTION:In order that a metal tube 3 being the outer cover of a cable body 2 is bisected into a pair of semicircular parts 13, 13 through a pair of slits 11, 11, where the central angle of the cross section of the cable body 2 with four slits 11, 11, 11, 11 formed therein is about 180 deg., the metal tube is puled in two directions A, A being opposite to each other and separated to form metal wastes 12, 12. In this case, respective semicircular parts 13 right after separation spared by themselves as shown by imaginary lines, around the slit 11 of non-split state to take flat, almost W-shaped cross sections. The thickness L of a metal waste 12 becomes very small in comparison with the first semicircular state, i.e., the metal waste 12 becomes almost flat, easily bends with a large curvature, abounds in flexibility, and can be prevented from tensil tearing due to buckling, etc.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for stripping ultrafine metal tubes.

[Problems to be solved by conventional techniques and inventions] Generally,
If an aluminum tube is manufactured by rolling a metal tape, for example, an aluminum tape into a circular tube shape and welding the abutting portions, the wall can be made thinner and long lengths with small diameters can be manufactured at low cost. It is particularly useful as an outer skin for preventing moisture and mechanical protection of cores of small-diameter electric wires, cables, etc. (hereinafter referred to as cable cores) whose internal properties deteriorate due to moisture absorption, etc.

By the way, in the above-mentioned aluminum tube, pinholes may occur in the welded portion due to slight changes in external factors such as minute fluctuations in the welding current or slight vibrations in the abutting portion. If there is a pinhole that penetrates the wall thickness of the tube, moisture will inevitably enter the aluminum tube, making it impossible to maintain the desired characteristics of the cable core built into the tube.

In particular, there are hundreds of strands with built-in cable cores.
If a defect such as a pinhole is found in a pressure test after welding, (conventionally,
Since there was no method for peeling off and removing such microtubules, the entire long striatum had to be discarded.

In order to solve these problems, the inventors of the present invention repeatedly conducted many trial-and-error experiments and arrived at the present invention.

For example, while running the filament in a straight line, two places on the metal tube, which is the outer skin, are cut in the longitudinal direction with a cutting blade to form a cut in the metal tube, and the cross section divided by the cut is halved. A method was attempted in which the arcuate portion was pulled in the outer diameter direction and the skin was peeled off by cutting each of the cuts.

According to this peeling method, the outer skin that is rolled up as waste material is divided into two semicircular arc-shaped sections, but these semicircular sections are easily bent (buckled) locally, and are made into ultra-thin aluminum tubes. In such cases, tensile breaks occur frequently due to local bending (buckling), which causes problems such as work being interrupted each time, damage to the built-in cable core, and deterioration of optical characteristics. Ta. Further, when the above-mentioned cuts were made at four or more locations and the skin was cut and peeled at each location, the cross-sectional area of the four semicircular portions was too small and the same problem occurred as the product was cut by tensile force.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a linear body with an ultra-fine metal tube, in which a built-in object such as a cable core is coated with an ultra-fine metal tube, while running it. Four cutting blades are pressed from four radial directions to form four longitudinal cuts, which are equally distributed with the center angle of the cross section being about 90°, and the center angle of the cross section is about 180°. It is divided into two semicircular parts forming a pair of semicircular parts (pulled in two opposite directions, and after separation, each semicircular part is expanded around the cut in the approximate center of the unseparated state to form a flat road W shape. Roll up as a cross section.

[For production]

Four longitudinal cuts are formed in an ultra-fine metal tube in four radial directions, with the center angle of the cross section being equally distributed at approximately 90°.
Cutting was performed at two opposing cuts, and the remaining unseparated cuts in the two directions were widened and wound into a flat W-shaped cross section, so there was no tensile breakage due to local bending (buckling). can be prevented.

Furthermore, since the outer skin, which is the metal tube, is pulled in the centrifugal direction and peeled off, external forces such as extra tension do not act on the built-in cable core.

〔Example〕

Hereinafter, the present invention will be explained in detail based on drawings showing examples.

FIG. 1 is a simplified diagram showing the method for peeling an ultra-fine metal tube according to the present invention, and the filament 2 with an ultra-fine metal tube fed out from the filament feeding mechanism 8 is as shown in FIG. A built-in material such as a core (cable core) of an electric cable or the like whose characteristics deteriorate due to moisture absorption is built in, and is covered with an ultra-fine metal tube 3 having an outer diameter of approximately 4 to 7 mm. Then, the filament body 2 is held in a straight line and is guided to travel and sent to the cutting mechanism 15. In FIGS. 1 and 2, the cutting mechanism 15 has four cutting blades 4, 4. is pressed to form four longitudinal cuts 11.11°11,11. The depth of the cut 11 is 50 to 90% of the wall thickness of the metal tube 3, preferably 55 to 75% (optimally 60 to 80%).

Next, a pair of cuts 11.11 in which the center angle of the cross section of the linear body 2 having four cuts 11.11.11.11 is about 180° In order to divide the metal tube 3 into a pair of semicircular parts 13 and 13, the metal pipe 3 is pulled in two opposite directions A and A, separated, and the metal waste 12
．． 12. At this time, each of the semicircular parts 1 immediately after separation
3 naturally expands as shown by the imaginary line around the approximately central cut 11 in the unseparated state (as shown in FIG. 2),
The road has a W-shaped cross section. That is, it is pulled while being curved in a direction to gradually separate from the built-in material 1 by the guide roll 6, and is further pressed by the drive roll 5a and the pressure roll 5b, so that it is deformed into a flat road W-shaped cross section. The metal scrap 12.12 is then wound onto the metal scrap winding mechanism 10.10. On the other hand, the cable core, which is the built-in object 1, is wound up by the built-in object winding mechanism 9 in a tension-free state. At this time, the thickness L of the metal waste material 12 becomes extremely small compared to the initial semicircular state, that is, the metal waste material 12 becomes a substantially flat state, easily bends to a large curvature, and becomes highly flexible. , tension breakage due to buckling etc. can be prevented.

In addition, in FIG. 1, the metal waste 12 is placed on the guide roll 6.
The metal waste material winding mechanism 10 sequentially takes up the metal waste material by pulling it by drive rolls 5a, 5a, etc. directly connected to the drive source 7.

The present invention is not limited to the illustrated embodiment, and the design may be changed without departing from the gist of the present invention.For example, the cutting blade 4.
... is preferably a fixed blade, but may be a rotating blade.

〔Effect of the invention〕

The present invention is configured as described above, and in particular, the four cuts 11
... are separated, and the remaining two unseparated cuts 11 are expanded around the center to be wound into a flat approximately W-shaped cross section. No bending (buckling) occurs and tension breakage can be prevented. As a result, it is possible to peel the ultra-thin metal tube 3 without interruption (continuously) from the long filament 2 of several hundred meters or more, and not only can a remarkable improvement in work efficiency be achieved, but also it is possible to peel off the built-in material 1 due to cutting.
(cable core) can also be reliably prevented from being damaged. Also,
Since the ultra-fine metal tube 3 is separated by pulling in two opposite directions to divide it into a pair of semicircular parts 13 whose cross-sectional center angles are approximately 180°, no external force such as tension is applied to the built-in material l. Therefore, there is no damage to the built-in component 1 (cable core), making it possible to fully reuse it.

Furthermore, only two metal waste winding mechanisms 10 are required.

[Brief explanation of drawings]

FIG. 1 is a simplified diagram showing one embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of a filament and a cross-sectional explanatory diagram showing changes in metal waste. 1...Built-in substance, 2...Striatum with ultra-fine metal tube, 3...
・Extremely thin metal tube, 4... Cutting blade, 11... Cut, 13
...Semicircle part.

Claims (1)

[Claims] 1. While running a linear body with an ultra-fine metal tube, in which a built-in component such as a cable core is coated with an ultra-fine metal tube, the metal tubes are equally distributed in four radial directions with a central angle of about 90° in the cross section. 4 cutting blades are pressed to form 4 longitudinal cuts, and the cross section is pulled in two opposite directions in order to divide into a pair of semicircular parts with a center angle of about 180°. A method for peeling an ultra-fine metal tube, characterized in that each of the separated semicircular portions is expanded around a substantially central cut in the unseparated state and then wound into a flat, substantially W-shaped cross section.