JPH0794086B2 - How to cut corrugated metal sheath of power cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] When assembling an end portion or an intermediate connection portion of a power cable having a metal sheath, it is necessary to cut and remove a predetermined length of the end portion of the sheath.

The present invention particularly relates to a method of cutting a sheath in a power cable having a metal sheath corrugated in a spiral shape.

[Prior Art] In FIG. 2a, 10 is a cable core.

20 is a metal sheath, and the peaks 22 and the valleys 24 are formed in a spiral shape.

When removing the end of the metal sheath 20, conventionally, regardless of the presence or absence of a wave, the metal sheath 20 is cut along a cutting line 30 perpendicular to the length direction of the cable with a gold saw, and then the The previous part had been removed (Fig. 2b).

[Problems to be Solved by the Invention] In the above method, one portion, that is, the valley 24 must be cut.

In that case, there is a possibility that the cable core 10 may be damaged by the blade 32 of the gold saw as shown in FIG. In many cases, the metal sheath 20 is scratched 12 when the valley 24 to be cut comes under the cable, which is likely to be a blind spot during work.

The present invention significantly reduces the probability of damaging the cable core when cutting off the end of the metal sheath, and improves the work stability.

[Means for Solving the Problem] As illustrated in FIG. 1a to FIG. 1d, (1) A continuous cut 40 is made in the crest 22 of the metal sheath 20. The strip-shaped portion 28 of the sheath is formed between the parallel cuts 40 over one round, and (2) the sheath 26 on the side to be subsequently cut is twisted in the direction opposite to the corrugated spiral direction, (3) Thereafter, the sheath is cut at the strip portion 28.

[Operation] In the mountain portion 22, there is a gap between the cable core 10 and the sheath 20. Therefore, it is possible to make the cut 40 in the metal sheath 20 without damaging the cable core 10.

Then, if the sheath 26 on the side to be cut is twisted in the direction opposite to the corrugated spiral direction, for example, if the spiral spring is twisted in the direction opposite to the spiral direction, the same reason that the spring diameter becomes large will cause the strip-shaped portion 28 to move outward. It swells and rises from the cable core 10.

[Embodiment] (Figs. 1a to 1d) (1) Cut the metal sheath 20 at the ridges 22 with a metal saw, a pipe cutter type cutting tool, a metal sheet cutter, etc.
Make 40 consecutively. The break 40 extends over more than one circumference of the sheath.

In Fig. 1a, when the starting point is 42, the cut 40 goes around the metal sheath 20 once, and when the point A is passed, the cuts 40 are arranged next to each other, and the band portion 28 of the sheath is formed between them. , And it is formed to form part of a helix.

In this case, the strip-shaped portion 28 is in a state of being easily deformed, unlike the other portions of the cylindrical metal sheath 20.

(2) After that, the sheath 26 on the side to be cut is twisted in the direction opposite to the corrugated spiral direction as shown by the arrow 34 (Fig. 1b).

Then, as described above, the strip portion 28 bulges outward and floats from the cable core 10.

In this embodiment, the cut 40 is provided so as to surround the metal sheath 20 almost twice, so that the band-shaped portion 28 that surrounds the core is formed.

It is not particularly limited to the number of two laps, but a break
If the metal sheath 20 goes around the metal sheath 20 for a considerably long time, the force required for twisting the sheath 26 on the side to be cut is small, and the amount of bulging to the outside of the band-shaped portion 28 is large, so that 40 is easy to cut. become.

(3) After that, a cut 48 is provided so as to cross the strip-shaped portion 28 from the vicinity of the starting end 42 of the cut 40 (Fig. 1c), and the sheath 26 on the cutting side is separated from the metal sheath 20.

(4) After that, pull out the sheath 26 on the side to be cut, and
Set as shown in Fig. 1d.

[Advantages of the Invention] (1) Since the cuts are continuously formed in the crest portion of the metal sheath, there is no fear of damaging the cable core at that time.

(2) Cuts are made continuously in the crests of the metal sheath so that the cut extends over more than one circumference of the sheath so that a band-shaped portion of the sheath is formed between the cuts, and then the cut side is cut off. Since the sheath is twisted in the direction opposite to the corrugated spiral direction, as described above, the strip portion bulges outward and floats up from the cable core, which may cause damage to the cable core when cutting the sheath at the strip portion. Completely disappears.

[Brief description of drawings]

1a to 1d are explanatory views showing the method of the embodiment of the present invention in the order of steps, FIGS. 2a and 2b are explanatory views showing the method of the prior art in the order of steps, and FIG. 3 is the illustration of the prior art. Illustration of the problem. 10: Cable core, 20: Metal sheath 22: Mountain, 24: Valley 26: Sheath on the side to be cut 28: Band-shaped portion, 32: Gold saw 40: Cut, 42: Start end 44: End, 46, 48: Cut

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Manabu Yoshida 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Electric Wire Co., Ltd. (56) References Japanese Patent Publication No. 37-18836 (JP, B1)

Claims (1)

[Claims] 1. When cutting an end portion of a metal sheath of a power cable having a metal sheath corrugated in a spiral shape, a cut is continuously made in a mountain portion of the metal sheath, and the cut is a sheath. A strip-shaped portion of the sheath is formed between the parallel cuts over one or more rounds, and then the sheath on the cutting side is twisted in a direction opposite to the corrugated spiral direction, and then the sheath is formed in the strip-shaped portion. How to cut the corrugated metal sheath of the power cable.