JP4689387B2 - Embedded structure grounding device - Google Patents

Description

  The present invention relates to an embedded structure grounding device installed in an embedded structure such as a manhole or a handhole embedded in the ground, or a pipe line disposed between these manholes or handholes.

  The buried structure grounding device protects workers from electric shocks during repair work of the distribution lines and communication lines arranged in the buried structure and the connected devices connected thereto, and the construction machine. And for grounding equipment.

  In recent years, laying of distribution lines, communication lines, etc. has been increasingly laid on underground lines instead of overhead lines, and grounding devices such as protection from workers' electric shock and grounding of construction machinery and equipment, etc. Under the stable grounding resistance, the line and the like are grounded, and the wiring work and the like are performed in a limited narrow space.

  A conventional buried structure grounding device has a through-hole formed in the side wall of a manhole, and a metal grounding rod is placed in the ground through the through-hole. The anode rod is provided by being placed in the ground, and the ground rod and the sacrificial anode rod are electrically connected.

  In the above-mentioned conventional buried structure grounding device, the metal grounding rod is electrochemically corroded by the electrolyte of the soil and the like to prevent the grounding resistance from increasing and maintaining the predetermined grounding function. In order to achieve this, the sacrificial anode rod electrically connected to the metal ground rod constitutes a so-called galvanic battery, thereby preventing the corrosion of the ground rod. Such an embedded structure grounding device is disclosed in Patent Document 1 as an example.

Japanese Utility Model Publication No. 63-50779

  In a conventional buried structure grounding device, as described above, a through hole for placing a grounding rod and a sacrificial anode rod in the ground is drilled on the side wall of a manhole or the like constituting the underground buried structure. Need to do so. After installing the grounding rod, sacrificial anode rod, and grounding conductor in the ground, the through hole must be waterproofed to prevent water from entering the manhole, etc. There was a problem that it took a great deal of labor, time and money.

  Further, the buried structure grounding device described above has a great effect of preventing the corrosion of the grounding rod by the sacrificial anode rod, but on the other hand, the sacrificial anode rod electrically connected to the grounding rod is consumed, and the sacrificial anode rod There was a problem that had to be replaced. Thus, since the sacrificial anode rod is consumed, it is necessary to replace the sacrificial anode rod. Therefore, there is a problem that the replacement of the sacrificial anode rod requires a lot of labor, time and cost.

  An object of the present invention is to solve the problems of the above-described conventional buried structure grounding device.

In order to achieve the above object, the present invention provides a conductive cement laid on the bottom of a manhole member, a grounding body disposed on the top surface of the conductive cement, and connects the grounding body and the manhole member. And holding the grounding body in a plurality of substantially U-shaped members fixed to the inner surface of the hook-shaped member along the longitudinal direction of the hook-shaped member. A conductive metal plate attached to the bottom plate portion of the holding plate, an end cap, an insulated conductor connected to the conductive metal plate, and a conductive cement filled in the bowl-shaped member it is those constructed in accordance with.

  Conductivity attached to the box of a manhole member in which the conductive cement and the grounding body are installed through the conductive cement filled in the recessed groove of the bowl-shaped member having insulating properties constituting the grounding body Since the grounding body is installed on the box of manhole members embedded in the ground via cement, the grounding body and the ground can be securely connected to the ground, and the hook-shaped member is insulated. Therefore, there is no risk of electric shock even if an operator touches the grounding body.

  Also, the conductive cement is attached to the box of the manhole member in which the conductive cement and the grounding body are installed through the conductive cement filled in the concave groove of the bowl-shaped member having insulating properties constituting the grounding body. Since the grounding body is installed in the box of manhole members embedded in the ground via conductive cement, a through-hole through which the grounding body and sacrificial anode rod are inserted into the box of manhole members Since there is no need for drilling, it is possible to prevent an increase in the cost associated with the drilling of such a through-hole and an increase in the length of the construction, and a waterproof sealing process for closing such a through-hole. There is no need, so it is possible to shorten the construction work of the buried structure grounding device and provide a semi-permanent buried structure grounding device that eliminates the need for repair of waterproofing parts and has no running costs. Do Door can be. Furthermore, since it is not necessary to install a sacrificial anode rod, it is possible to save labor, time and cost conventionally required for exchanging the sacrificial anode rod.

  Further, the conductive cement is attached to the box of the manhole member in which the conductive cement and the grounding body are installed through the conductive cement filled in the concave groove of the bowl-shaped member having insulating properties constituting the grounding body. Since the grounding body is installed in the manhole member box embedded in the ground via conductive cement, contact resistance increases due to corrosion of the contact surface between the manhole member box and the grounding body. Can be prevented.

  A conductive metal plate is attached to the concave groove of the bowl-shaped member constituting the grounding body via a holding plate, and a grounding conductor member to which an insulated conductor is connected is attached to the conductive metal plate. Since the conductive metal plate and the ground conductor member are embedded in the conductive cement filled in the concave groove of the bowl-shaped member, corrosion of the holding plate, the conductive metal plate and the ground conductor member is prevented. be able to.

  Examples of the present invention will be described below. However, the present invention is not limited to these examples as long as the gist of the present invention is not exceeded. In the following, an embodiment of the present invention will be described using an example in which the buried structure grounding device is installed in a manhole constituting the buried structure.

  In FIG. 1, reference numeral 1 denotes a manhole member such as a manhole or a handhole. The manhole member 1 is provided with a substantially cylindrical entrance / exit portion 1a, a line 2 such as a distribution line or a communication line, and a grounding body 3 described later. And a lid 1c covered by the upper opening of the entrance / exit part 1a. The manhole member 1 is embedded in an excavation space excavated in the ground G so that the lid 1c covered by the upper opening of the entrance / exit portion 1a is exposed to the ground surface GL. The manhole member 1 is made of concrete, synthetic resin or the like except for the lid 1c formed of a metal such as a casting.

  In one side wall 1b1 of the box 1b constituting the manhole member 1 described above, a line hole 1b2 for drawing the line 2 such as a distribution line or a communication line into the box 1b is formed.

  3 is a grounding body, and the grounding body 3 is formed of an insulating long bowl-shaped member 3a shown in FIG. 2, and a copper material, a titanium material, etc. shown in FIG. An end cap made of an insulating material shown in FIG. 5 disposed at the end of the elongated strip-shaped conductive metal plate 3b, the holding plate 3c shown in FIG. 4, and the flange-like member 3a 3d, a grounding conductor member 3e shown in FIG. 6, and a conductive cement 3f made of carbon and cement or the like filled in the bowl-shaped member 3a. As shown in FIG. 5, as an example, the end cap 3d includes a semicircular sealing wall 3d1 and an arc side of the sealing wall 3d1, and stands substantially perpendicular to the sealing wall 3d1. An arcuate peripheral wall 3d2 is provided.

  The flange-shaped member 3a has a recessed groove 3a1, and a hole 3a2 is formed at a predetermined position. In addition, the conductive metal plate 3b is formed to have substantially the same length as the flange-shaped member 3a, and a plurality of holes 3b1 are formed in the conductive metal plate 3b along the length direction. . Further, the holding plate 3c has a substantially U-shaped side surface by a bottom plate portion 3c1 and side plate portions 3c2 arranged so as to stand upright from the bottom plate portion 3c1 at both ends of the bottom plate portion 3c1. In addition, a hole 3c1 ′ is formed in the bottom plate portion 3c1. Furthermore, the insulated conductor 3e1 constituting the ground conductor member 3e is electrically connected to a connection terminal 3e2 having a hole 3e2 '.

  Next, the assembly of the bowl-shaped member 3a, the conductive metal plate 3b, the holding plate 3c, the end cap 3d, and the ground conductor member 3e constituting the grounding body 3 will be described.

  First, as shown in FIG. 7, the holding plate 3c is arranged in the recessed groove 3a1 of the bowl-shaped member 3a with a predetermined interval, and the inner surface of the bowl-shaped member 3a and the holding plate 3c are arranged. The side plate portion 3c2 is fixed with an appropriate adhesive or the like. Next, the conductive metal plate is aligned so that the hole 3b1 formed in the conductive metal plate 3b and the hole 3c1 ′ formed in the bottom plate portion 3c1 of the holding plate 3c are aligned with the bottom plate portion 3c1 of the holding plate 3c. 3b is placed. Thereafter, the bolt B is inserted into the hole 3b1 ′ formed in the bottom plate portion 3c1 of the holding plate 3c and the hole 3b1 formed in the conductive metal plate 3b, and the nut N is screwed into the bolt B. Thus, the conductive metal plate 3b is attached to the bottom plate portion 3c1 of the holding plate 3c. At this time, the predetermined conductive hole 3b1 formed in the conductive metal plate 3b (in this embodiment, the third hole 3b1 from the right as shown in FIG. 7) is located. The holding plate 3c is not disposed on the metal plate 3b, and the bolt B is not inserted into the predetermined hole 3b1.

  Next, as shown in FIG. 8, the hole 3b1 through which the bolt B of the conductive metal plate 3b is not inserted and the hole 3e2 'drilled in the connection terminal 3e2 constituting the ground conductor member 3e, After the ground conductor member 3e is arranged on the back surface of the conductive metal plate 3b so as to match, the hole 3b1 formed in the conductive metal plate 3b and the connection terminal 3e2 constituting the ground conductor member 3e are formed. By inserting the bolt B into the hole 3e2 'and screwing the nut N into the bolt B, the grounding conductor member 3e is attached to the conductive metal plate 3b, so that the conductive metal plate 3b and the grounding conductor are attached. The member 3e is electrically connected. Thereafter, the free end of the insulated conducting wire 3e1 constituting the ground conductor member 3e is inserted into the hole 3a2 drilled in the bowl-shaped member 3a, and the free end of the insulated conducting wire 3e1 is inserted as shown in FIG. The terminal board 4 is connected to the entrance / exit part 1a of the manhole member 1 or the like. Next, end caps 3d are put on both ends of the hook-shaped member 3a, and the end caps 3d are fixed to both ends of the hook-shaped member 3a with an appropriate adhesive or the like.

  As shown in FIG. 9, after assembling the bowl-shaped member 3a, the conductive metal plate 3b, the holding plate 3c, the end cap 3d, and the ground conductor member 3e constituting the grounding body 3, end caps at both ends are assembled. The concave groove 3a1 of the bowl-shaped member 3a to which the 3d is fixed is filled with raw conductive cement 3f obtained by kneading carbon and cement with water, and the raw conductive cement 3f is hardened, thereby grounding. The body 3 will be constructed.

  Next, a raw conductive cement similar to the conductive cement 3f obtained by kneading the carbon and cement with water is attached to the upper surface of the bottom 1b3 of the box 1b of the manhole member 1 to a predetermined thickness. After that, the grounding body 3 is placed so that the conductive cement 3f filled and hardened in the recessed groove 3a1 of the bowl-shaped member 3a constituting the grounding body 3 is brought into contact with the raw conductive cement. At the same time, the ground conductive body 3 is installed on the bottom 1b3 of the box 1b of the manhole member 1 by curing the raw conductive cement attached to the upper surface of the bottom 1b3 of the box 1b.

  In the embodiment described above, the conductive cement 3f filled in the recessed groove 3a1 of the bowl-shaped member 3a constituting the grounding body 3 is replaced with the manhole member 1 through the conductive cement similar to the conductive cement 3f. Although the example which made the grounding body 3 install in the manhole member 1 by making it contact with the box body 1b of this is shown, the grounding body 3 which is not filled with the conductive cement 3f is shown in the bowl-shaped member 3a. Is disposed on the bottom 1b3 of the box 1b of the manhole member 1 so that the recessed groove 3a1 is located on the box 1b side of the manhole member 1, and then the cement filling machine is placed in the recess 3a1 of the bowl-shaped member 3a. The grounding body 3 can also be configured to be installed in the manhole member 1 by filling the raw conductive cement 3f with the like and then curing the raw conductive cement 3f.

  As described above, the grounding body 3 composed of the bowl-shaped member 3a, the conductive metal plate 3b, the holding plate 3c, the end cap 3d, the ground conductor member 3e, and the conductive cement 3f is used as the box 1b of the manhole member 1. The buried conductor grounding device of the present invention is configured by connecting the insulated conductor 3e1 of the grounding conductor member 3e constituting the grounding body 3 to the manhole member 1 through the terminal plate 4 become.

  In the above-described embodiment, an example in which the conductive metal plate 3b is formed of a single metal plate is shown, but the conductive metal plate 3b is connected to a plurality of short metal plates. It can also be configured. As described above, it is difficult to form the conductive metal plate 3b by connecting a plurality of short metal plates. However, as a material for the conductive metal plate 3b, there is a difficulty in workability, but titanium having excellent corrosion resistance. This is particularly effective when using materials.

  Moreover, although the example which installed the grounding body 3 in the bottom part 1b3 of the box 1b which comprises the manhole member 1 is shown in the Example mentioned above, the grounding body 3 is shown in the inner surface of the side wall 1b4 of the box 1b. It can also be attached to (the surface located in the box 1b) or the inner surface (the surface located in the box 1b) of the top 1b5. Further, the grounding body 3 is connected to the outer surface of the bottom 1b3 of the box 1b (the surface positioned outside the box 1b), the outer surface of the side wall 1b4 (the surface positioned outside the box 1b), and the outer surface of the top 1b5 (box It can also be attached to the surface located outside the body 1b.

  As described above, the grounding body 3 is connected to the box body of the conductive cement 3f and the manhole member 1 through the conductive cement 3f filled in the concave groove 3a1 of the bowl-shaped member 3a constituting the grounding body 3. Since it installed in the box 1b of the manhole member 1 through the conductive cement attached to 1b, the grounding body 3 and the ground G can be reliably connected to the ground, and the bowl-shaped member 3a is insulative. Therefore, even if an operator touches the grounding body 3, there is no risk of electric shock.

  Further, the conductive cement 3f is filled in the box 1b of the manhole member 1 embedded in the ground G via the conductive cement 3f filled in the recessed groove 3a1 of the bowl-shaped member 3a constituting the grounding body 3. Since the grounding body 3 is installed in the manhole member 1 through the conductive cement attached to the box 1b of the manhole member 1, the contact surface between the manhole member 1 and the grounding body 3 is corroded. It is possible to prevent an increase in contact resistance due to.

  Further, as described above, the grounding body 3 is installed in the manhole member 1 without drilling a through-hole for attaching the grounding body 3 to the manhole member 1 embedded in the ground G. Therefore, there is no need for a waterproof sealing treatment work that closes the through-hole formed in the manhole member 1, so that the construction work of the buried structure grounding device can be shortened and the waterproof seal is sealed. A semi-permanent buried structure grounding device can be provided that does not require repair of the stop point and therefore has no running cost.

  Furthermore, since the grounding body 3 is attached to the box 1b of the manhole member 1 with a small specific resistance embedded in the soil of the ground G, a buried structure grounding device having a low grounding resistance can be provided easily and inexpensively. Obtainable.

  Furthermore, the conductive cement 3f filled in the recessed groove 3a1 of the bowl-shaped member 3a constituting the grounding body 3 or the conductive cement 3f and the conductive material attached to the box 1b of the manhole member 1 are provided. Since the grounding body 3 is configured to be installed on the box 1b of the manhole member 1 through cement, no special fixing member or mechanical member is required. Therefore, the grounding body 3 is narrow in the manhole member 1. It can be easily and quickly installed at a place.

  Still further, a conductive metal plate 3b is disposed in the recess groove 3a1 of the bowl-shaped member 3a constituting the grounding body 3 via a holding plate 3c, and an insulated conductor 3e1 is connected to the conductive metal plate 3b. Install the grounding conductor member 3e. Furthermore, since the holding plate 3c, the conductive metal plate 3b, and the ground conductor member 3e are embedded in the conductive cement 3f, corrosion of the holding plate 3c, the conductive metal plate 3b, the ground conductor member 3e, etc. can be prevented. it can.

  In the embodiment described above, an example is shown in which the holding plate 3c is not provided in the conductive metal plate 3b portion to which the ground conductor member 3e is attached. At the conductive metal plate 3b portion to which 3e is attached, the side plate portion 3c2 of the holding plate 3c is fixed to the inner surface of the bowl-shaped member 3a with an appropriate adhesive or the like, thereby attaching the holding plate 3c. The hole 3c1 'drilled in the bottom plate portion 3c1 of the holding plate 3c and the hole 3e2' drilled in the ground conductor member 3e connection terminal 3e2 are aligned, and bolts B are fitted in these holes 3c1 'and 3e2'. The ground conductor member 3e can also be attached to the conductive metal plate 3b on which the holding plate 3c is disposed by inserting a nut N into the bolt B.

FIG. 1 is an overall perspective view of an embedded structure grounding device and the like according to the present invention. FIG. 2 is a perspective view of a bowl-shaped member constituting the grounding body of the buried structure grounding apparatus of the present invention. FIG. 3 is a perspective view of a conductive metal plate constituting the grounding body of the buried structure grounding apparatus of the present invention. FIG. 4 is a perspective view of the holding plate constituting the grounding body of the buried structure grounding apparatus of the present invention. FIG. 5 is a perspective view of an end cap constituting the grounding body of the buried structure grounding apparatus of the present invention. FIG. 6 is a perspective view of a ground conductor member constituting the grounding body of the buried structure grounding apparatus of the present invention. FIG. 7 is a perspective view of the grounding body constituting the buried structure grounding device of the present invention during assembly. FIG. 8 is a perspective view of the grounding body constituting the buried structure grounding device of the present invention in the middle of assembly. FIG. 9 is a perspective view of a state in which the grounding body constituting the embedded structure grounding device of the present invention is assembled.

Explanation of symbols

G ························· GL ······· grounding body 3a ··········· 3b ···············································・ ・ ・ End cap 3e ・ ・ ・ ・ ・ ・ ・ ・ Grounding conductor 3f ・ ・ ・ ・ ・ ・ ・ ・ Conductive cement 4 ・ ・ ・ ・ ・ ・ ・ ・ Terminal board

Claims (1)

The conductive cement is laid on the bottom of the manhole member, the grounding body is disposed on the top surface of the conductive cement, and the insulated conductor connecting the grounding body and the manhole member. and sex of the trough-shaped member, along the longitudinal direction of the該樋member, a plurality of substantially U-shaped holding plate which is fixed to the inner surface of the trough-shaped member, is attached to the bottom plate portion of the holding plate Embedded structure comprising: an electrically conductive metal plate; an end cap; an insulated conductor connected to the electrically conductive metal plate; and an electrically conductive cement filled in the bowl-shaped member. Grounding device.

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