JPH0116252Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the improvement of overhead electric wires such as overhead power transmission lines, and particularly aims to provide an overhead electric wire that prevents snow accumulation.

Conventional overhead electric wires that prevent snow from accumulating are those in which a linear body is wrapped around the outer periphery of the electric wire, and the linear body acts as an obstacle to cause snow that has accumulated on the wire to fall.

However, with this electric wire, the wire must be attached by a separate operation, and if the wire breaks, it will hang down, so as an improvement to this problem, a circular element wire was used as shown in Figures 1 and 2. In an overhead wire constructed by twisting the wires into multiple layers, a deformed strand 2 having a substantially triangular cross section in a part of the outermost layer of the wire 1 and having an uneven portion 3 formed at the top along its longitudinal direction is used. We have proposed a method in which the strands 2 are twisted and pressed against the adjacent circular strands 4.

However, the cross-sectional shape of this wire changes rapidly at the edges A and A' of the recess shown in Figure 1A, so when the wire vibrates, stress concentrates on these edges, causing the deformed wire to fatigue. It becomes easy to disconnect.

The present invention was developed as a result of intensive research aimed at improving these shortcomings, and has developed an overhead power line that can prevent snow from accumulating without the risk of wire breakage. That is, the present invention provides an overhead wire constructed by twisting circular wires into multiple layers, in which a part of the outermost layer of the wire has a substantially triangular cross section, and a top portion along the longitudinal direction of the wire has a shape that is parallel to the axis. A grooved wire having a plurality of intermittent diagonally extending grooves is twisted together, and the grooved wire is pressed by an adjacent circular wire.

In the present invention, the reason why the grooves of the grooved wire are provided so as to extend diagonally with respect to the axis is that by providing the grooves, when the snow attached to the wire slides downward along the twisted groove, it is stopped at this part. , so they are prevented from moving and fall before the snow increases significantly, but
On the other hand, the provision of grooves reduces the strength of the strands, and particularly when the grooves are provided at right angles to the strands, the strength of the strands is significantly impaired. This is also because if grooves are provided along the axis of the wire, there is almost no effect of preventing snow buildup. Further, the preferable inclination angle of the groove is 75 to 80 degrees.

The depth of the groove is not particularly limited, but it is usually about 1 mm, and its shape can be such that it is deep at the center and becomes shallower toward the sides.

Next, one example of the present invention will be explained with reference to the drawings. Third
Figures A and B show grooved strands 5 in the overhead electric wire of the present invention.
The grooved wire 5 is made of metal or plastic, has a substantially triangular cross section, and has a plurality of grooved wires arranged at desired intervals along its longitudinal direction at the top. A circular groove 7 is provided. Further, the groove 7 has a shape extending obliquely to the axis of the strand 5. The grooved strands 5 are twisted into the outermost layer of a stranded wire formed by twisting together a large number of circular strands 4 as shown in FIGS. The overhead electric wire 8 of the present invention is obtained by pressing the circular strands.

As detailed above, according to the overhead wire of the present invention, the grooved wire has a substantially triangular cross section, so it can be held down well when twisted with the circular wire, so even if it breaks, it will not sag. It does not fall down, and since the groove is provided to extend obliquely to the axis of the strand, the area occupied by the groove in any cross section is smaller than that of conventional products, and it has excellent strength against vibrations and breaks. Not only does this not happen, but it also has a sufficient effect to prevent snow from accreting. In addition, since no protrusions are formed on the surface of the electric wire, the characteristics of all vehicle passages are good, and since it can be manufactured in a factory, it has remarkable effects such as improved productivity.

[Brief explanation of the drawing]

Fig. 1 shows a deformed wire twisted into a conventional overhead electric wire, A is a front view, B is a side view, Fig. 2 is a sectional view showing an example of a conventional overhead electric wire, and Fig. 3 is a cross-sectional view showing an example of a conventional overhead electric wire.
The figures show grooved strands twisted into the overhead electric wire of the present invention, A is a front view, B is a side view, and Figures 4 and 5 show an example of the overhead electric wire of the present invention.
FIG. 4 is a plan view, and FIG. 5 is a sectional view. 1... Conventional overhead electric wire, 2... Modified wire, 3...
Uneven portion, 4... Circular strand, 5... Grooved strand, 6
...Triangular surface, 7...Groove, 8...Overhead electric wire of the present invention.

Claims (1)

[Scope of utility model registration request] In an overhead electric wire constructed by twisting circular wires into multiple layers, a part of the outermost layer of the wire has an almost triangular cross section, and the top part has a wire extending along the longitudinal direction and diagonally to the axis. An overhead electric wire characterized in that grooved wires each having a plurality of grooves at desired intervals are twisted together, and the grooved wires are pressed together by adjacent circular wires.