JPH10125367A - Grounding member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metallic member, capable of being deformed pertinently and easily, and properly giving the specified resistance value through the enlargement of an effective area by forming a plurality of cuts on a metallic plate so as to be communicated to both the upper and reverse sides thereof, and enabling the plate to be expanded. SOLUTION: A square metallic plate of high conductivity, such as copper and aluminum is divided into four sections A to D. Then, linear cuts 2 of small breadth are formed on each of the sections A to D, and communicated to both of the upper and reverse sides thereof, with the front and rear positions dislocated from each other the center of a cross-shape part Z without cuts is provided with a connection part 3 such as a bolt hole, and a grounding member is thereby prepared. The overall shape of the grounding member can be deformed and easily manufactured in a factory. In addition, a large number of grounding members so formed are capable of being carried and stored in a stacked state. Also, the effective area of the grounding member can be enlarged by expanding cur parts approximately twofold into a mesh-type in a factory, thereby providing a resistance value equal to or less than the preset value. Furthermore, a grounding conductor 5 can be easily connected to the connection part 3 via a bolt or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a transformer, a lightning arrester,
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grounding member used in grounding work such as a steel tower or a telephone pole to which a high-voltage device or the like is attached.

[0002]

2. Description of the Related Art Grounding work is required by law to prevent accidents due to earth leakage on power poles equipped with transformers, lightning arresters, high-voltage equipment, and the like. This grounding work is performed by embedding a grounding member at a predetermined depth around the pole position and connecting a grounding wire to the grounding member.

Conventionally, in embedding work of this grounding member, a grounding member such as a metal rod is driven into the ground with a hammer, and the electric resistance value of the embedded grounding member is measured. If you had passed.

[0004]

However, the conventional grounding member has a small surface area for its volume, and its shape and area are constant irrespective of the diameter of the telephone pole. In many cases, the specified electrical resistance value could not be obtained.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a grounding member in which the shape of the grounding member can be appropriately changed, the effective area is widened, and it is easy to reliably obtain a specified resistance value.

[0006]

In order to solve the above problems, the present invention employs the following configuration. That is, the grounding member according to the present invention is characterized in that the grounding member is formed of an expandable metal plate having a plurality of cuts penetrating the front and back.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific examples of the grounding member of the present invention will be described. As shown in FIG. 1, this grounding member 1 is formed by cutting a large number of cuts 2 penetrating from front to back into a flat metal plate 1a rich in conductivity, such as copper or aluminum. The cuts 2,... Are for expanding the metal plate. In the illustrated example, the ground plate 1 is divided into four sections (A,
B, C, D), and linear cuts (grooves) 2 having a small width are alternately shifted in front and rear positions in each section, but the size, shape, direction, etc. of the cut 2 are Not limited to Between the sections, an unbroken portion Z is provided in a cross shape, and a ground line (lead wire) connecting portion 3 is provided at the center (although it may be an end, but the center is preferable because it has better balance). (In the illustrated example, bolt holes). A ground wire 5 is connected to this connection portion by an appropriate means (in the illustrated example, a connection is made with a bolt inserted into a bolt hole), but the connection may be made in a factory, or the connection may be made at a construction site. You may.

[0008] Since this grounding member is formed by cutting a metal plate, it can be easily mass-produced in a factory. And since it is a plate-shaped and does not bulky, many can be superimposed and it is convenient for conveyance, storage, etc. In addition,
Instead of using a bolt or the like, the ground wire may be connected by other appropriate means such as brazing or welding.

At the time of construction at the burial site, the grounding member can be deformed into a desired shape and size by stretching or bending. In this case, since many cuts 2,... Are made, this deformation is easy. FIG. 2 shows an example of this modification, but is not limited to this and can be modified into various shapes.

FIG. 3 shows a method of burying the grounding member. First, a utility pole hole 7 having a predetermined depth is formed at a predetermined position by a suitable drilling device. The depth of the drill hole is set to be 30 cm or more deeper than the burial depth (rooting depth) of the utility pole. When a hole 7 having a predetermined depth is formed, the bottom of the hole 7 is filled with a conductive bottom filler (for example, lime powder) 8 to a predetermined depth to evenly level the surface. On the other hand, telephone pole 10 to be built
Around the lower end of the ground wire 15 pulled down along the utility pole (or through the interior of the utility pole) from the upper part of the utility pole, is temporarily fixed with a tape 11 or the like at an appropriate position below the utility pole.

The ground plate 1 is expanded in accordance with the utility pole hole 7 and placed on the bottom filler 8 of the utility pole hole 7. At this time, the distance from the lower end of the telephone pole to the ground plate 1 is a reference value (usually 30 cm).
That's it. Then, a filled soil 9 such as an improved soil in which a conductivity improving material (the same type as the bottom filler 8 and the like) is mixed into the excavated soil to a predetermined depth from above the grounding plate 1,
Roll it once or twice with a con pillar. After that, the base of the utility pole is put on it, and the ground wire 15 on the utility pole side and the ground wire 5 on the ground plate 1 side are placed.
Are connected, and the filled soil 9 or excavated soil is further filled around the utility pole. At this time, care must be taken to ensure that the depth at which the utility pole is buried and the distance from the lower end of the utility pole to the ground plate 1 have predetermined values. As a result, the construction work for the pole and the ground is completed, but if the ground resistance is higher than the specified value, the renovation work will be performed separately.

As the filler, ordinary soil can be used, but it is preferable to use a conductivity improving material for improving conductivity, such as lime-based powder. The lime-based powder is
This is also advantageous because it is alkaline and does not corrode the grounding members or wires made of copper. Furthermore, if an alkaline lime-based powder is used as a filler, effects such as neutralization of acidic soil and incorporation of underground heavy metals can be expected.

[0013]

Embodiments of the present invention will be specifically described below. A plurality of alternate cuts 2,... Penetrating the copper plate were formed at 10 mm intervals in the width direction of a rectangular copper plate of 100 × 400 × 1 mm as shown in FIG. A connecting portion (bolt hole in the illustrated example) 3 for connecting a ground wire is provided at the center of the grounding member 1.

When the grounding member 1 is buried, as shown in FIG. 2, the cut portion is made about 50% of the original length.
The connecting portion 3 is further extended in the length direction to form a mesh-like expanded structure, and the connecting portion 3 is provided with a ground wire 5 by a bolt, a nut,
The connection was made by tightening with a washer or the like. Needless to say, any connection method may be used as long as both can be electrically connected.

On the other hand, as shown in FIG.
A utility pole hole 7 was drilled. The drilling depth was about 5 m, and the diameter was about 200 mm.

When a telephone pole hole 7 having a desired depth is formed,
After the filler 8 and the grounding member 1 were inserted in the above procedure, the filler 9 was filled. In this state, the resistance was measured, and a resistance lower than the specified value of 10Ω was obtained.
Subsequently, soil was filled, and the opening (depth 0.75 m) was filled with topsoil to complete the embedding.

The grounding member 1 can have a shape and structure other than those described above. The cut 2 has a narrow linear groove shape as shown in FIG. 4 as shown in FIG. 1, but has a circular enlarged portion 2 at both ends as shown in FIG.
6, 2a having a rhombus shape as shown in FIG. 6, 2c having a triangular enlarged portion 22 at the center as shown in FIG. As shown in FIG. 9, various types such as a drum-shaped object 2 d in which the central portion 23 is gradually narrowed from both sides, and an object 2 e in which the central portion 24 is gradually narrowed from one side as shown in FIG. As shown in FIGS. 5 to 9, it is preferable to form a cut having a portion having a different width or an edge portion because the deformability is improved. Such cuts (grooves) can be easily formed by punching or the like. The cuts 2,... Are preferably independent from each other, but may be partially continuous in some cases.

[0018]

As described above, the grounding member according to the present invention has a thin plate shape before use, so that it is convenient for storage and transportation, and the area and volume can be expanded when buried. This is preferable because the effective area is wide and a resistance value equal to or less than a specified value can be obtained. In addition, since the entire shape can be deformed, it is excellent in adaptability to the situation at the site, the embedding condition, and the like.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a grounding member of the present invention.

FIG. 2 is an external view of a grounding member expanded to a mesh structure.

FIG. 3 is an explanatory view of a method of burying a grounding member.

FIG. 4 is an explanatory diagram of a cut shape.

FIG. 5 is an explanatory diagram of different cut shapes.

FIG. 6 is an explanatory diagram of different cut shapes.

FIG. 7 is an explanatory diagram of different cut shapes.

FIG. 8 is an explanatory diagram of different cut shapes.

FIG. 9 is an explanatory diagram of different cut shapes.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ground member 2 Cut 3 Connection part 5 Ground wire 7 Utility pole hole 8 Filler 10 Utility pole

Claims (1)

[Claims] 1. A grounding member connected to a grounding wire and buried in the ground, wherein the grounding member is formed of an expandable metal plate having a plurality of cuts penetrating from front to back.