JPS6236452B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for retaining a POF cable connection part in order to prevent the cable connection part from moving beyond the allowable movement amount due to thermal expansion and contraction or wave riding phenomena.

BACKGROUND OF THE INVENTION An example of a conventional method for retaining a POF cable connection section is shown in "Fig. 1."

10 is a cable, 12 is a connection portion, 14 is a connection box, and 16 is a skid wire. Near the connection part 12, connect the skid wire 16 to the binding wire 1.
8, and the tip 160 of the skid wire 16
is connected to the junction box 14, taking into account the allowable movement amount (approximately 50 to 200 mm).

In "Figure 1" and "Figure 2" below, only one phase of the POF cable core is shown. Further, only the left side of the connecting portion 12 is shown as a retainer (the same method is used on the right side (not shown) as needed).

As the connection 12 moves to the right in FIG. 1, the tip 160 of the skid wire 16 becomes taut, preventing further movement. Further, when the connecting portion 12 moves to the left, the tip 160 of the skid wire 16 on the right side (not shown) acts in a similar manner to prevent movement beyond the allowable movement amount.

However, the connecting portion 12 may move more than the allowable amount of movement due to a large force. In such a case, the skid wire 16, while being tied to the binding wire 18, rubs against the surface of the cable 10 and becomes displaced. At this time, the stainless steel tape wrapped around the cable 10 may shift inadvertently, damaging the cable insulation and even causing an accident.

However, it is possible to take appropriate measures (such as increasing the number of turns of the binding wire 18 to a very large extent, or increasing the number of turns of the skid wire 18).
If the skid wire 16 strongly grips the cable 10 by wrapping a rubber sheet between the cable 10 and the skid wire 16 (see experimental example below), it is possible to prevent the connection part 12 from moving beyond the permissible amount of movement. You can also do it. However, it has been found that when a large force is applied to move the cable, the cable 10 twists due to the large tension on the skid wire 16, causing wrinkles in the cable insulation paper.

The object of the present invention is to provide a method for retaining a POF cable connection portion that does not have the above-mentioned problems.

Structure of the first invention (1) In a section of appropriate length near the connection part 12, the skid wire 16, which was conventionally wound only in one direction, is changed to the left-hand skid wire 162 and the right-hand skid wire 162 in FIG. (2) The skid wire 16 wound in both directions strongly grips the cable 10 at at least one location within such a bidirectionally wound section; (3) One end of the skid wire 16 wound in both directions is connected to the junction box 14.

Configuration of the second invention (1) Using the ring 21 placed over the cable 10, the skid wire 16 is folded back, and an appropriate section is wound in the opposite direction. (2) The cylindrical portion 30 and the disc 32 are integrated into one body. The bent clamp fitting 28 is fixed in the junction box 14, the cylindrical part 30 thereof is placed over the ring 21, and the movement of the ring 21 is restrained using the inner surface of the cylindrical part 30. shall be.

In addition, when winding the skid wire 16 on both the left and right sides, fold back one skid wire 16,
You can wrap it back in the opposite direction or use another skid wire. In the embodiments described later, the above-mentioned folding method is used.

Also, the skid wire 16 connects the cable 1
A specific method for strongly grasping 0 will be described in the following example.

In addition, one end of the skid wire 16 may be connected to the junction box 14 by a straight line connection (the fifth
2), or the skid wire 16 may be connected to a suitable member (for example, the ring 21 in FIG. 2) and then connected to the junction box 14.

Embodiment (FIG. 2) Reference numeral 21 is a ring, which is inserted into the folded portion of the skid wire 16 as described above. This is used to make the folding process easier and to ensure that the retaining force is applied evenly around the circumference of the cable. Moreover, this is a short cylindrical part, and the tip 210 is thick and rounded. Also, before connecting the cable conductor, cover the cable 10 in advance.

Place the rubber sheet 20 on the cable skid wire near the junction box 14 at an appropriate interval (approximately 20 to 30 cm), and wrap the rubber sheet 24 just above the cable core. The ring 21 is placed over the rubber sheet 24 near the junction box 14.

If the skid wire on the cable 10 is left-handed, for example, the end AB portion of the left-handed skid wire 162 is wound inside the ring 21 near the connection 12. Then turn around at B, pass BC through the outside of ring 21, and CDEF
Then, turn it to the right and return while overlapping it on top of the left-handed skid wire 162.

The end of the right-handed skid wire 164 is
For example, on the rubber sheet 20, the bind line 22 is tightly wound over the GH part, the HJ part is folded over the bind line 22, and the HJ part is further bound from above (however, this binding is not shown). The skid wire grips the cable 10 tightly.

Also, near the ring 21, the rubber sheet 24 and the intersecting skid wires 16 in both left and right directions are
2. Wrap the binding wire 26 over 164 so that the skid wire firmly grips the cable 10.

Then, use one end 36 of a suitable tensile strength wire 36 (skid wire may be cut to an appropriate length and used).
0 is connected to the ring 21 by, for example, welding, and the other end 362 is connected to the junction box 14 with a predetermined allowable movement amount.

In addition, in "Fig. 2", skid wire 1
Only one 6 was shown. However, in reality, many windings (for example, four) are wound with different phases. The same procedure as above is then taken for each of these skid wires.

Other embodiments (1) In the case of FIGS. 3 and 4 In the case related to the second invention, the skid wire 16
To hold down the folding ring 21, a clamp fitting 28 as shown in FIG. 3 is used instead of the above-mentioned tensile strength wire 36.

The clamp fitting 28 is made up of a cylindrical portion 30 and a disk 32, which are split into three pieces at a split line 34, and can be assembled by appropriate means (not shown).

The cylindrical portion 30 is placed over the ring 21 as shown in FIG. Also, the disk 32 is the connection box 1
Fix it to the inner surface of 4. On the inner surface of the cylindrical portion 30,
A taper 300 is provided at one end (the direction in which the cable 10 is likely to move). Also cable 1
Considering the case where 0 moves in the opposite direction, a stopper 302 is also provided at the opposite end.

As cable 10 moves to the left in FIG. 4, ring 21 is pulled against taper 300 and is prevented from further movement. If a split is made in the ring 21, a large brake will be applied to the ring 21 by the action of the wedge, making it more effective.

When such a clamp fitting 28 is used, 3
The holding forces of the three cables 10 (that is, the amount of movement of the cables 10) are equal, and the three cables 1
There will be no relative deviation between 0 and 0.

(2) In the case of FIG. 5 Instead of using the ring 21 as described above, the folded part ABC of the skid wire 16 is made longer and hooked to the stopper 38 provided on the junction box 14.

(3) In the case of Fig. 6, do not bend the end of the folded right-handed skid wire 164 as shown above, but leave it as it is on the GKM.
Stretch it out and connect it to the junction box 14.

Experimental Example 1 In the method shown in "Figure 2", rubber sheets 20 and 24 with a thickness of 2 mm are each wound twice with a distance of 407 mm (L in Figure 2), and the binding wire 26 is
Three turns of 2.6mmφ tin-plated mild steel wire were made at two locations. In addition, the bind wire 22 is a tightly wound wire of the same plated wire, and a right-handed skid wire 1 is placed on top of it.
I bent the HJ part of 64 and bound the same plating line on it in 3 turns and 3 places. The cable constructed in this manner was able to withstand a tension of 750 kg and did not damage the insulation of the cable 10.

Experimental Example 2 In the method shown in Figure 1, in which the skid wire 16 was wound only in one direction, a 2 mm rubber sheet was wrapped twice, and then the same 2.6 mmφ plated wire 18 as above was wrapped over a length of 140 mm. It was tightly wrapped. In this case, it was possible to hold the cable 10 under a tension of 750 kg, but the cable 10 was twisted and wrinkles appeared on 17 sheets of insulating paper from the outside.

Effects of the Invention The skidded wire is wound in both left and right directions, and at least one location within the bidirectional winding section,
After making sure that the skid wire has a strong grip on the cable, connect one end of the skid wire to junction box 1.
4 to hold the connection part 12, the movement of the connection part can be kept within an allowable amount against strong pulling force, and the cable is not twisted.

Furthermore, in the second aspect of the invention, the retaining forces between the three cables are particularly equal, and relative displacement does not occur.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the prior art, Fig. 2 is an explanatory diagram of an embodiment of the first invention, Fig. 3 is a schematic perspective view of the clamp fitting 28 used in the second invention, and Fig. 4 is its usage state. FIG. 5 and FIG. 6 are explanatory diagrams of another embodiment of the first invention. 10: Cable, 12: Connection part, 14: Connection box, 16: Skid wire, 21: Ring for folding skid wire, 28: Clamp fitting, 3
0: Cylindrical part.

Claims (1)

[Claims] 1. A skid wire is wound in both left and right directions in a section of an appropriate length near the connection part, and the skid wire wound in both directions grips the cable strongly at at least one location within the bidirectional winding section. and connecting one end of the bidirectionally wound skid wire to a connection box.
How to hold the POF cable connection. 2. Fold back the skid wire using a ring placed over the cable near the connection point, and return while winding the skid wire in the opposite direction for a section of an appropriate length, so that the skid wire wrapped in both directions wraps around the cable at least at one point within the bidirectional winding section. A clamp fitting made of a cylindrical part and a disc is fixed in the junction box, and the cylindrical part is placed over the ring, and the inner surface of the cylindrical part is used to tighten the ring. A method for retaining a POF cable connection portion, characterized by restricting movement.