JPH1118259A - Grounding electrode for concrete electric pole and grounding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain elimination or reduction in labor and efficiency of installation work without requiring large man-hours labor required for setting up a grounding electrode by mounting a metallic cover in a lower surface of a hollow cylinder wall, and connecting a grounding wire to this metallic cover with the metallic cover serving as the grounding electrode. SOLUTION: In a lower end of a concrete electric pole 2, a metallic cover 1 is mounted so as to fit a lower end 4a of a reinforcing steel 4 and a groove 1a of the metallic cover 1, and a lower end of a grounding lead wire 3 is connected to a protrusion thereof. On the other hand, a hole for vertically building the concrete electric pole 2 is left as being excavated, the concrete electric pole 2 mounting the metal cover 1 is built vertically, so as to bury a total unit of the metal cover 1 in the ground. Next, an upper end of the grounding lead wire 3 is connected on the ground to a lower end of a grounding wire connected to a ground wire which is separately mounted in an upper end of the concrete electric pole 2, a safety cover is mounted. In this way, labor for excavating a grinding electrode-embedding hole and for embedding a grinding electrode is omitted, so that the elimination or the reduction of labor and efficiency of work can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to
The present invention relates to a ground pole and a grounding method for a concrete electric pole for protecting personal safety and electric equipment.

[0002]

2. Description of the Related Art When erection of this type of concrete electric pole,
Grounding electrodes are installed based on facility standards and grounding resistance that conform to electrical equipment technical standards. For example, as shown in FIG. 5, a grounding line c connected to a grounding line b laid on the upper end of a concrete power pole a is laid along the concrete power pole a inside a safety cover e made of synthetic resin having an insulating effect. Through the ground to reach the ground and buried underground
Connected to.

[0005] As shown in FIGS. 5 and 6, the concrete electric pole a is hollow, and a plurality of rebars f are built in a cylindrical shape in a cylindrical wall thereof, and the lower end protrudes from the lower surface of the concrete electric pole a. It is necessary to excavate at least about 1.1 m as the depth of embedding of the concrete pole a. However, the burial of the grounding pole d is also about the same level.
m or more).

[0004] The concrete utility pole a is hollow,
If it is buried as it is, the underground sand or the like may enter from the hollow lower surface and the utility pole may sink, so it is necessary to cover the lower surface. Therefore, conventionally, a concrete lid g as shown in FIG. 6B has been attached. The lid g has a central portion protruding so as to fit into the inner periphery of the cylindrical wall of the concrete utility pole a, and a plurality of notches h corresponding to the reinforcing bars f are provided on the outer periphery so that the reinforcing bars f are fitted. ing. Accordingly, the lid g is fitted to the lower surface of the concrete utility pole a by fitting the central portion thereof to the inner periphery of the cylindrical wall of the concrete utility pole a and the outer periphery provided with the notch h to the periphery of the reinforcing bar f. After the fitting, the outer periphery is caulked with concrete and closed.

Since the ground electrode d is rod-shaped, a plurality of ground electrodes must be buried in the ground in order to enhance the effect of reducing the electric resistance. When the resistivity of the soil is high, the soil is improved by using a liquid ground resistance reducing material containing a conductive powder.

[0006]

However, in the case of the above-described conventional earth pole d of the concrete utility pole a, it is necessary to excavate a buried hole other than the concrete utility pole a to a depth of the same for the installation. There is a problem that labor and effort are required for that. Also, the rod-shaped ground electrode d as described above
It is necessary to bury a plurality of ground electrodes d in order to increase the surface area of the conductor as much as possible to reduce the electrical resistance.
The labor and labor for burial increase accordingly. Therefore, there has been a demand for the development of a grounding electrode capable of reducing the labor and labor of the excavation work required for the grounding as much as possible and improving the work efficiency.

The present invention reduces the electric resistance and exerts the grounding effect without requiring much labor and labor for the installation of the grounding electrode as in the prior art, thereby achieving labor saving and efficient installation work. It is an object of the present invention to provide a ground pole and a grounding method for a concrete electric pole that can be used.

[0008]

According to the present invention, in order to achieve the above object, a ground wire connected to a ground wire installed at the upper end of a concrete telephone pole is replaced with a concrete formed of a hollow cylindrical wall having a reinforcing bar. At the grounding pole of the concrete power pole laid along the power pole and connected to the ground wire, a metal cover is attached to the lower surface of the hollow cylindrical wall, and the metal cover is grounded by connecting the ground wire to the metal lid. It is characterized by a pole.

Further, according to the present invention, a ground wire connected to a ground wire erected at the upper end of a concrete power pole is laid along a concrete power pole formed of a hollow cylindrical wall having a built-in rebar and connected to the ground wire. In a grounding method for connecting to a ground pole of a concrete utility pole, a metal lid is attached to a lower surface of the hollow cylindrical wall, and the ground wire is connected to the metal lid, thereby making the metal lid a ground pole. .

[0010] According to the ground pole and the grounding method of the concrete power pole of the present invention, the ground wire laid on the concrete power pole for the purpose of grounding is connected to the metal lid attached to the lower surface of the hollow cylindrical wall. Since the conductive metal lid can maintain good electrical contact with the ground under a large ground area, the ground resistance can be greatly reduced. In addition, the concrete pole can be grounded without using a special grounding pole as in the past, and the drilling hole for the construction of the concrete pole can also be used as the ground pole burial hole. Therefore, it is possible to save the labor and labor for arranging the grounding electrodes in a special manner and burying them, thereby improving the work efficiency.

When the reinforcing bar is connected to the metal cover, the reinforcing bar built into the concrete cylindrical wall is also connected to the ground line via the metal cover, so that the reinforcing bar is electrically connected to the soil through the cylindrical wall. Contact That is, the grounding resistance is reduced even between the periphery of the cylindrical wall and the underground, and a groundable area is increased between the metal lid and the ground, which is preferable.

Further, according to the present invention, a ground wire connected to a ground wire erected at the upper end of a concrete power pole is laid along a concrete power pole consisting of a hollow cylindrical wall containing a reinforcing bar, and is connected to the ground wire. In a ground pole of a concrete electric pole, a metal wire is wound around a reinforcing bar protruding from the lower surface of the hollow cylindrical wall, and the ground wire is connected to the metal wire to make the metal wire a ground pole.

According to the ground pole of the concrete pole of the present invention, the ground wire laid on the concrete pole for the purpose of grounding is connected to the metal wire attached to the lower surface of the hollow cylindrical wall. The conductive metal wire can maintain good electrical contact with a sufficient ground area with the ground, so that the ground resistance can be sufficiently reduced and a commercially available inexpensive metal wire can be used. Therefore, the cost of parts can be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a side view showing a state in which a metal cover 1 serving as a ground electrode according to the present embodiment shown in FIGS.

The concrete utility pole 2 has a hollow cylindrical wall 2a.
A bar-shaped reinforcing bar 4 is incorporated. A plurality of main reinforcing bars 4 (hereinafter referred to as reinforcing bars) are arranged at equal intervals in the longitudinal direction,
Spiral bars not shown in the horizontal direction with respect to the reinforcing bars 4
By being arranged in a spiral shape so as to surround the outer peripheries of a large number of rebars 4, the rebars 4 are reticulated and built in the cylindrical wall 2a.

The lower end 4a of the reinforcing bar 4 protrudes from the lower surface of the concrete electric pole 2, and the lower end 4a is
Is inserted into a circumferential groove 1a formed in the metal cover 1 attached to the lower surface of the metal cover 1. The metal cover 1 is made of copper and has a thin outer wall 1.
Although the b and the bottom 1c are integrally formed, the cylindrical outer peripheral wall 1b and the bottom 1c may be formed separately from different materials. On the outer peripheral wall 1b, a projection 1d for attaching the ground lead wire 3 is integrally formed. A recess 1e is formed in the center of the bottom 1c, and a drain hole 1f is formed in the center of the recess 1e.
Is provided.

In the grounding method according to the above configuration, first, a metal cover 1 is attached to a lower end of a concrete utility pole 2 so that a lower end 4a of a reinforcing bar 4 and a groove 1a of the metal cover 1 are fitted. Connect the lower end of the ground lead 3. here,
Temporarily fixing the upper part of the grounding lead wire 3 along the outer periphery of the concrete utility pole 2 improves workability afterwards. On the other hand, a hole for erecting the concrete utility pole 2 is excavated. And
The concrete utility pole 2 to which the metal cover 1 is attached is erected so that the entire metal cover 1 is buried underground. At this time,
It is preferable that a grounding resistance reducing agent is put around the metal lid 1. Next, the upper end of the grounding lead wire 3 is connected on the ground to the lower end of a grounding wire c connected to a grounding wire b erected separately on the upper end of the concrete utility pole 2, and a safety cover e is attached (FIG. 5 which is a conventional drawing). reference).

In the above grounding method, before the concrete utility pole 2 is erected, a safety cover e is attached to the outer periphery of the concrete utility pole 2 in advance, and the upper portion of the ground lead wire 3 is held in the safety cover e. Is also good.

The concrete electric pole 2 and the metal cover 1 are knocked into each other by fitting the lower end 4a of the reinforcing bar 4 into the groove 1a of the metal cover 1 and press-fitting the lower end of the concrete electric pole 2 and the outer peripheral wall 1b of the metal cover 1. Be combined. Therefore, the metal cover 1 and the reinforcing bar 4 are electrically connected to the ground line c through the ground lead wire 3 connected to the metal cover 1. The metal lid 1 can sufficiently reduce the grounding resistance between the metal lid and the underground and can have a sufficient grounding area. In the present embodiment, in addition to this, the reinforcing steel bar 4 is provided on the concrete cylindrical wall 2a and the main reinforcing steel bar is spirally mounted. Since the reinforcing bars are wound and wound in a mesh shape, the reinforcing bars are electrically connected to the ground via the cylindrical wall 2a by connecting the reinforcing bars to the ground line c. That is, the grounding resistance is reduced even between the periphery of the cylindrical wall 2a and the ground, and the groundable area is increased between the metal lid 1 and the ground.

As described above, according to the present invention, the work of attaching the metal cover 1 to the concrete utility pole 2 can be performed on the ground before the concrete utility pole 2 is erected. Can be omitted. Further, in the present embodiment, the grounding effect can be exhibited by reducing the grounding resistance by utilizing the existing concrete power pole 2 such as a reinforcing bar and a lid, and the installation work of the grounding pole (metal cover 1) is also performed. Excavation holes for the construction of 2 can be used as ground hole buried holes, which can save labor and improve work efficiency.

If the ground resistance value is below the standard depending on soil conditions, a conventional ground electrode such as a ground rod is used in combination. In that case, the grounding rod should be buried at least 1 m away from the reinforcing bar 4 and the metal lid 1.

The present invention can be configured in various modes in addition to the embodiments described above. For example, the metal cover 1 attached to the lower surface of the concrete utility pole 2 is not limited to the material and shape shown in the above embodiment, but may be a metal cover 5 made of sheet metal as shown in FIG. In this case, the lower end 4a of the reinforcing bar 4
It is preferable that the lower circumferential portion 5a of the metal lid 5 is formed to be inclined in a reverse taper shape so that the metal lid 5 can be easily connected to the metal lid 5.

As described in the above embodiment, the metal cover 1 connected to the ground line c can sufficiently reduce the ground resistance between the metal cover 1 and the ground, so that the metal cover 1 and the lower end 4 of the reinforcing bar 4 can be used.
The object of the present invention is achieved without connecting a.

In the above embodiment, the metal lids 1, 5 attached to the lower surface of the concrete utility pole 2 are ground electrodes.
If there is no danger that the concrete utility pole 2 will sink into the ground, a copper wire is attached without attaching the metal lids 1 and 5 so as to surround the lower ends 4a of a large number of reinforcing bars 4 arranged in a circle from the outside. The copper wire may be wound and connected to the ground wire c to use the copper wire as a ground electrode, and the same effect as described above can be obtained.

[0026]

According to the concrete pole and method of the present invention, the ground wire is connected to the metal cover attached to the lower surface of the hollow cylindrical wall of the concrete power pole, and the conductive metal cover is connected to the metal cover. Good electrical contact can be maintained with a large grounding area between the ground and the ground resistance can be greatly reduced, and the existing concrete telephone pole lid can be replaced with a grounding pole without the need for a special grounding pole as in the past. In the installation work, the excavation hole for the construction of the concrete utility pole can be used as the hole for burying the ground pole, and the work can be saved and the efficiency can be improved.

When the reinforcing bar is connected to the metal cover, the reinforcing bar built into the concrete cylindrical wall is also connected to the ground line via the metal cover, and the reinforcing bar is electrically connected to the soil through the cylindrical wall. Because it is in contact, the ground resistance between the metal lid and the ground can be reduced, and the ground resistance can be reduced between the periphery of the cylindrical wall and the ground to expand the groundable area,
It is suitable.

Further, according to the ground pole of the concrete utility pole of the present invention, the ground wire is connected to the metal wire attached to the lower surface of the hollow cylindrical wall so that the conductive metal wire is sufficiently connected to the ground. Since good electrical contact can be maintained with a large ground area, the ground resistance can be sufficiently reduced, and a commercially available inexpensive metal wire can be used, so that the cost of parts can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing one embodiment of the present invention and showing a state where a metal lid is attached to a lower end of a concrete utility pole.

FIG. 2 is a longitudinal sectional side view showing an embodiment of a metal cover serving as a ground electrode.

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is a longitudinal sectional side view showing another embodiment of the present invention.

5A and 5B show a conventional example, in which FIG. 5A is a side view in which a part thereof is cross-sectionally viewed, and FIG.

FIG. 6 (a) is a plan view of a concrete power pole as viewed from below, and FIG. 6 (b) is a plan view of a lid attached to a lower end of the concrete power pole as viewed from the back.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal cover (grounding pole) 2 Concrete utility pole 2a Cylindrical wall 3 Grounding lead wire 4 Reinforcement b Ground wire c Grounding wire

Claims (4)

[Claims] 1. A concrete electric pole connected to a concrete electric pole composed of a hollow cylindrical wall having a reinforcing bar and connected to a ground line provided at an upper end of the concrete electric pole, and connected to the ground line. A metal lid is attached to a lower surface of the hollow cylindrical wall, and the ground wire is connected to the metal lid, thereby making the metal lid a ground electrode. 2. The earth pole of a concrete electric pole according to claim 1, wherein a reinforcing bar is connected to the metal lid. 3. A concrete power pole which is laid along a concrete power pole consisting of a hollow cylindrical wall containing a reinforcing bar, and which is connected to a ground wire erected at the upper end of the concrete power pole. Wherein a metal wire is wound between rebars projecting from the lower surface of the hollow cylindrical wall, and a ground wire is connected to the metal wire to make the metal wire a ground electrode. very. 4. A concrete power pole connected to a concrete power pole consisting of a hollow cylindrical wall containing a reinforcing bar, and a ground wire connected to a ground wire installed at an upper end of the concrete power pole is connected to the ground wire. A grounding method, wherein a metal cover is attached to the lower surface of the hollow cylindrical wall, and the grounding wire is connected to the metal cover, thereby making the metal cover a grounding electrode.