JPS60257010A - Snowfall preventing transmission line - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a snow-accumulation-preventing power transmission line that prevents snow that has settled on the surface of the wire from accumulating and developing into a cylindrical shape. be.

(Prior art and its problems) When snow adheres to the surface of a power transmission line made of stranded conductors during snowfall, this snow gradually develops and eventually accumulates in a cylindrical shape around the outer periphery of the wire.

The structure of the power transmission line can be considered to be the cause of such cylindrical accumulation of snow.

In other words, since power transmission lines generally have a stranded wire structure in which a large number of wires with a circular cross section are twisted together, relative movement is possible between the wires forming each layer of twisted wire and between the inner and outer twisted wire layers. Therefore, the torsional rigidity of the overall structure is low.

If we consider Figure 3 even when a power transmission line with low torsional rigidity is under snow removal conditions, snow S will adhere to a part of the surface of the power transmission line W, as shown in Figure (A), and this will cause When it develops to a certain size, it becomes an eccentric load, and the electric wire W with low torsional rigidity receives a rotational moment and is twisted and rotated in the circumferential direction of itself as shown by the arrow (a), and the above snow accretion position S■ becomes the fourth position. It changes as shown in figure (B). Then, new snow S■ adheres to the area on the outer periphery of the electric wire W that was previously occupied by snow S■, as shown in Fig. 1 (B), and as before, this eventually becomes a large eccentric load and causes the electric wire W to become Twist and rotate further,
Thereafter, the same action is repeated as shown in FIGS. 4(C) to 4(E), and finally the snow S1 to S2 is deposited in a cylindrical shape on the outer periphery of the electric wire W.

This cylindrical accumulation of snow is largely due to the low torsional rigidity of power transmission lines, as mentioned above.For this reason, conventional methods have been used to attach weights to power transmission lines to prevent snow from accumulating on power lines. Technology to prevent twisting/rotation (Utility Model No. 59-28233)
However, in this case, there are concerns such as fatigue due to stress concentration of the wire at the weight attachment part and accidents of the weight falling off, etc. The maintenance work must be strictly inspected, which significantly increases the burden of maintenance work, and the actual weight of the wires increases, leading to an increase in the tension required to keep the wires at a specified level of slack. This led to problems such as the need to make other structures more solid.

(Object of the Invention) The present invention provides a snow-accumulation-preventing overhead power transmission line that prevents snow from accumulating in a cylindrical shape by increasing the torsional rigidity of the electric wire while minimizing the increase in the weight of the electric wire. The purpose is to provide

(Structure of the Invention) The present invention is characterized in that the outermost layer of a power transmission line is formed by a plurality of segment wires gathered together to form a pipe shape as a whole, and the outer periphery of the outermost layer is tightened to form the pipe shape. The segment wires are pressed together and integrated by tightening with
The torsional rigidity of the outermost layer is increased.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the snow accumulation prevention type power transmission line according to the present invention, in which the outermost layer 1 of the power transmission line W is formed by a plurality of segment wires 2 assembled to form a pipe shape as a whole. 2, and the outer periphery of the outermost layer 1 is occupied by a clamping body 3 such as a brace-formed rod, so that the segment wires 2 are integrally pressed together as shown in FIG. be. According to this structure, the polar moment of inertia of the outermost layer 1 of the power transmission line W is significantly larger than that of the conventional case where the outermost layer 1 is made of twisted strands of circular cross-sectional wires, ).

The resistance to twisting shown in (b) is significantly improved.

Therefore, even if snow S as shown in FIG. 3(A) occurs on the surface of the power transmission line W, the outermost layer 1 does not twist and rotate in its own circumferential direction, and the snow S accumulates in a cylindrical shape. The development of children is hindered.

In the embodiment shown in FIG. 1, the outermost layer 1 is formed by assembling a plurality of segment wires 2 in parallel to the axial direction so as to form a pipe shape as a whole. 2 may be twisted and assembled to form a pipe shape as a whole.

In addition, if the surface of the outermost layer 1 is smooth in the circumferential direction, there is a risk that the snow itself will slide along the wire surface in the circumferential direction and develop into a cylindrical shape. Therefore, the surface of the outermost layer 1 may be provided with irregularities.

(Effects of the Invention) According to the present invention, the outermost layer of a power transmission line is formed by a plurality of segment wires assembled to form a -5-゛ pipe shape as a whole, and the outermost layer forming the pipe shape is Since the outer periphery is tightened by a tightening body and the segment wires are integrated by pressure bonding to each other, it is possible to significantly increase the torsional rigidity of the outer layer of the power transmission line without attaching a weight as in the conventional method. It is possible to effectively prevent snow from developing into a cylindrical pile.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the snow accumulation prevention type power transmission line according to the present invention, Fig. 2 is a cross-sectional view taken along the U-11 line in Fig. 1, and Fig. 3 shows snow accumulation in a cylindrical shape. It is an explanatory diagram of the phenomenon that occurs. W...Power line, S...Snowing, 1...
... Outermost layer, 2 ... Segment wire, 3 ...
...Tightening body. 6- Figure 1 Written amendment to the procedure (voluntary) 1. Indication of the case Patent Application No. 114295 of 1982 2. Name of the invention Snow accretion prevention type power transmission line 3. Person making the amendment Relationship to the case Patent applicant (518) #'Kura Densen Co., Ltd. 4, Agent May 5, 2-1 Yaesu, Chuo-ku, Tokyo, Column ``Detailed explanation of 1 invention in the specification subject to amendment''. 6. Correction details 1- (1) Correct "snow removal" in line 10 of page 2 to "snowfall". [2] Correct "case mo" in line 11 of page 2 to "case". (3) Correct ``Figure 4 Figure 1'' to ``Figure 3'' on page 2, line 17. (4) Correct “Figure 1, Figure 4” on page 2, line 18, to “Figure 3”. (5) Correct “Figure 1, Figure 4” in line 1 of page 3 to “Figure 3”. I”d

Claims (2)

[Claims] (1) The outermost layer 1 of the power transmission line W is formed by a plurality of segment wires 2 assembled to form a pipe shape as a whole, and the outer periphery of the pipe-shaped outermost layer 1 is the clamping body 3 A snow-accumulation prevention type power transmission line characterized by being tightened by. (2) The snow accretion prevention type power transmission line according to claim 1, wherein the outermost @10 surface is provided with irregularities.