JPH0139054Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a cable retention section.

When power cables are installed at an angle or vertically, upward cable extension is resisted in the manhole conduit to avoid the cable sliding downwards due to heat cycling of the power cable. A cable anchorage with directional resistance is required to have a resistance of several 100 kg against downward extension. In the prior art, a cleat that grips the cable is used as such a cable retention part, and this cleat is slidably supported via a compression spring so as to resist the movement of the cable in the sliding direction. is supported to freely allow movement in the opposite direction. On the other hand, due to space constraints within the manhole, the dimensions of the retaining part are usually
The length is limited to approximately 500 mm, and within this range it is required to obtain a retaining portion that has as large a retaining force as possible. If the cable is an oil-filled cable, this cable has a metal sheath, so the cleat can be manually tightened to a maximum torque of about 500 to 600 kg cm, so it is possible to obtain a retaining force of about 1000 kg. However, since the cable is a CV cable and does not have a metal sheath, it is not possible to apply a large external pressure to the insulator, and the maximum pressure is 0.5Kg/mm.
The cleat is required to be tightened using a spring having a predetermined spring constant. However, since the cable's retention force is given as a frictional force proportional to the surface pressure, the above-mentioned tightening force could only provide a maximum retention force of 200 kg.

An object of the present invention is to provide a cable retention section that can obtain a large retention force without requiring a large clamping force.

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a cable retaining section 10 according to the present invention.
, and this cable retention part 10 is connected to the cable 12
It consists of a packing material 14 fixed by adhesive to the outer peripheral surface of the packing material 14, and a gripping tool 16 fixed to a fixing base 13 and attached to grip the packing material 14.

The packing material 14 is made of, for example, an elastomer such as neoprene rubber containing aromatic polyamide fibers as a reinforcing material to increase the shear strength in the axial direction of the cable. Further, on the outer peripheral surface of the packing material 14, as shown in FIG. 2, a plurality of tapered protrusions 14a whose width changes at a taper angle α are spaced apart in the circumferential direction so that the width becomes smaller in the sliding direction of the cable 12. It is provided. The packing material 14 is additionally fixed at both ends with a non-magnetic binder 18 such as stainless steel tape.

The gripping tool 16 is an upper and lower gripping member 16 divided into two parts.
The lower gripping member 16B is screwed to the fixed base 13, and the upper and lower gripping members 16
A and 16B are mutually tightened with bolts 17. On the inner surface of this gripping tool 16,
As shown in the figure, a plurality of tapered grooves 16a corresponding to the tapered protrusions 14a of the packing material 14 are provided. This tapered groove 16a is connected to the tapered protrusion 14.
Cable 12 should be 1.0 to 2.0 mm deeper than the height of a.
The tapered protrusion 14a has a smaller taper angle β than the taper angle α of the tapered protrusion 14a. In addition, taper groove 1
In order to absorb the radial expansion of the cable 12, the total width of the wires 6a needs to be at least 1/5 of the inner circumference of the gripping tool, and therefore, as shown in 1 if it has a tapered groove 16a
The groove width of each tapered groove 16a is required to be 1/30 or more of the inner circumferential length. The number of tapered protrusions and tapered grooves is arbitrarily set in consideration of the cable diameter and the moldability of the packing material.

In this way, the tapered protrusion 1 of the packing material 14
4a, and the gripping tool 16 is provided with a corresponding tapered groove 16a. Therefore, when the cable 12 tries to extend in the sliding direction, the tapered protrusion 14a of the packing material 14 acts as a wedge and the side surface in the width direction of the tapered groove 16a. tightly engages to prevent its movement. Note that the gripping tool 16 has upper and lower gripping members 16A, 1
Since it is sufficient to tighten the cable 6B to the extent that it does not shift relative to the packing material 14, the allowable surface pressure of the cable 12 does not exceed 0.5 kg/mm.

In the above embodiment, the tapered protrusion 14a and the tapered groove 16a are tapered so that the width changes in the longitudinal direction of the cable, but they may also be tapered so that the height changes in the longitudinal direction of the cable.

According to the present invention, as mentioned above, it is possible to obtain a large retaining force with a small tightening force, so especially for CV
It is suitable for the retaining part of cables that cannot be tightened with a large tightening force like cables.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of the cable retaining part according to the present invention, Fig. 2 is a side view of the packing material installed,
FIG. 3 is a side view of the cable retaining part of the present invention. 10... Cable retention part, 12... Cable,
13... Fixed stand, 14... Packing material, 14a
...Tapered groove, 16...Gripper, 16a...Tapered groove.

Claims (1)

[Claims for Utility Model Registration] (1) Comprising a packing material adhesively fixed to the outer peripheral surface of a cable and a gripping tool attached to grip the packing material and fixed in a predetermined position, the packing material The material has a tapered protrusion on its outer peripheral surface that is tapered in the direction in which the cable slides down, and the gripping tool has a tapered protrusion on its inner surface that corresponds to the taper of the tapered protrusion, and the gripping tool has a tapered protrusion on its inner surface that corresponds to the taper of the tapered protrusion when the cable moves in the direction in which the cable slides down. A cable anchorage characterized in that it has a tapered groove that tightly engages in a wedging action but allows movement of said cable in the opposite direction. (2) The cable retaining portion according to claim 1, wherein the taper of the tapered projection and the tapered groove is a taper whose width changes in the longitudinal direction of the cable. (3) The cable retaining portion according to claim 1, wherein the taper of the tapered projection and the tapered groove is a taper whose height changes in the longitudinal direction of the cable.