JP2008267000A - Lead-in pole - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lead-in pole which facilitates reduction of earth resistance when erected in the ground. <P>SOLUTION: The lead-in pole 1 is formed of a support 9 and a tip mounting tool 5 arranged at the tip of the support 9. The tip mounting tool 5 is formed of an underground introduction portion 10, a support holding portion 11, and a spacer 12 arranged between the former and the latter. The cup-shaped underground introduction portion 10 which is fitted from below a lower end of the support is provided with an earth wire mounting portion 26 to which an earth wire 8 is attached. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pull-in pole for drawing a lead-in wire such as a power line or a communication line.

FIG. 7 shows a pull-in pole of the background art. FIG. 7 shows a case where the pull-in pole is used as a temporary pull-in pole. The temporary pull-in pole 100 is a pole for pulling in the power line 101 and attaching the switchboard 102 to which the construction electric appliance is connected. The temporary pull-in pole 100 is formed in a cylindrical shape. The switchboard 102 is provided with a grounded outlet into which a cord for supplying power to the electric appliance is inserted.
The switchboard 102 is grounded by connecting a ground wire 103 to a ground bar 104. The grounding rod 104 is inserted into the ground by hand placement. The ground wire 103 is protected by a pipe P.

  By the way, it is recommended that the distance between the switchboard 102 and the ground is 500Ω or less. For this reason, a ground rod 104 that is a separate body from the pole 100 is driven deeply or grounded by a plurality of ground rods to reduce the distance between the switchboard 102 and the ground to 500Ω or less. . For this reason, there has been a problem that the work for reducing the distance between the switchboard 102 and the ground to 500Ω or less is troublesome.

  Further, since the lower end of the pole 100 is opened in a cylindrical shape, earth and sand are clogged at the lower end of the pole 100 when the pole 100 is driven into the ground. For this reason, when this pole 100 is used for temporary installation, when the pole 100 is reused, work for removing earth and sand clogged in the lower end of the pole 100 has been difficult.

  For this reason, it has hitherto been desired to make it possible to easily reduce the grounding resistance to 500Ω or less when standing the lead-in pole without requiring a troublesome work.

  The present invention has been made in view of the background art described above. The purpose of the present invention is to prevent the intrusion of earth and sand into the pull-in pole, and to easily make the grounding resistance when standing the pull-in pole to be 500Ω or less. An object of the present invention is to provide a retractable pole that can be used.

The invention according to claim 1 is a lead-in pole for drawing in the lead-in wire,
A pipe-shaped column and a cup-shaped underground introduction part that covers the lower end of the column from below,
The underground introduction portion includes a ground wire attachment portion, and a ground wire is attached to the ground wire attachment portion.

  According to a second aspect of the present invention, in the lead-in pole according to the first aspect, the ground wire attaching portion is formed in a protrusion shape protruding in a wedge shape downward from a lower end of the underground introduction portion. It is characterized by this.

The invention according to claim 3 is the pull-in pole according to claim 1 or 2,
The underground introduction part is equipped with a column holding part that is inserted into the column from below, and the column holding unit is elastically inserted into the column by inserting the column holding unit into the column from the bottom of the column. It is characterized by being held.

  According to a fourth aspect of the present invention, in the pull-in pole according to any one of the first to third aspects, the upper portion of the support column holding portion is a scoop-shaped earth and sand cleaning portion. It is what.

  According to a fifth aspect of the present invention, in the lead-in pole according to any one of the first to fourth aspects, the lead-in line is a power line or a communication line.

  The invention according to claim 6 is the lead-in pole according to any one of claims 1 to 5, wherein the ground wire mounting portion is embedded at a depth of 1 to 1.5 meters. It is what.

  According to the first aspect of the present invention, since the ground wire attaching portion is provided integrally with the support column at the lowermost end of the support column, the ground wire is pressed more strongly against the surrounding earth and sand by the weight of the support column. Since there is no gap between the earth and sand, the ground resistance can be reduced. In addition, since the lowermost end of the support is covered with the underground introduction part, intrusion of earth and sand into the support is prevented, and the trouble of cleaning the support is not required, so that it can be easily prepared for reuse. .

  According to the second aspect of the present invention, since the ground wire mounting portion is formed in a wedge shape, the ground wire mounting portion bites into the ground and comes into close contact with the ground without a gap. Thus, the grounding resistance between the ground wire attachment portion and the ground can be reduced.

  According to the invention described in claim 3, the pull-in pole can be assembled elastically.

  According to invention of Claim 4, earth and sand (slag etc.) adhering to the support | pillar can be easily scraped off by the earth and sand cleaning part.

  According to invention of Claim 5, it can use when drawing in a power line and a communication line as a lead-in line.

  According to the sixth aspect of the present invention, the ground wire mounting portion is buried at a depth of 1 meter to 1.5 meters, so that the ground resistance can be further reduced.

  1 to 5 show a first embodiment. This 1st Embodiment shows the case where the drawing pole 1 is used for temporary installation. FIG. 1 shows the appearance of the ground portion of the pull-in pole 1. FIG. 2 shows a state in which the pull-in pole 1 is erected. FIG. 3 shows a perspective view of the tip fitting 5 provided at the lower end of the pull-in pole 1. 4 shows a right side view of FIG. FIG. 5 shows a cross-sectional view taken along line AA of FIG.

  As shown in FIG. 1, the lead-in pole 1 is a pole for drawing in the lead-in wire 6. The lead-in line 6 corresponds to a power line or a communication line. This 1st Embodiment demonstrates the case where the electric power line 6 used for construction is drawn. In the middle of the pull-in pole 1, a switchboard 3 is attached and a power line 6 is connected.

  As shown in FIG. 2, the switchboard 3 is provided with a grounded outlet to which a cord 7 of a construction electric appliance is connected so that electric power can be supplied to the electric appliance. A ground wire 8 is connected to the ground terminal of the switchboard 3.

  As shown in FIG. 3, the pull-in pole 1 is configured to include a support column 9 and the distal end fixture 5 provided at the end of the support column 9. The appearance of the tip fitting 5 is shown in FIG. In FIG. 3, the support column 9 is indicated by a one-dot chain line.

  The support column 9 has a pipe shape. The support 9 is formed of a steel pipe. For example, the support 9 may be formed by connecting two pipe-shaped steel pipes in two upper and lower stages, but may be formed by a single pipe-shaped steel pipe.

  As shown in FIGS. 3 to 5, the distal end fixture 5 includes an underground introduction portion 10, a support column holding portion 11, and a spacer 12 provided between the underground introduction portion 10 and the support column holding portion 11. It has a structure.

  The underground introduction part 10 is provided at the lower end of the support 9, can guide the support 9 easily to be driven into the ground, and prevents a phenomenon that earth and sand enter the support 9. As shown in FIG. 5, the underground introduction part 10 is formed in a cup shape in which the upper side of the cylindrical part 13 is opened and the lower side is closed by a hemispherical bottom part 14. Bolt through holes are formed in the bottom portion 14. This underground introduction part 10 is formed of resin.

  As shown in FIG. 5, the column support part 11 is formed in a shape in which the upper side of the cylindrical part 15 is opened and the lower side is closed by a flat bottom part 16. This support | pillar holding | maintenance part 11 is formed in the trumpet shape which expands diameter upwards. The upper part of the support | pillar holding | maintenance part 11 is the cleaning part 17 of scoop-like earth and sand, as shown in FIG. 3, FIG. Bolt through-holes are formed in the bottom 16 of the support holder 11. This support | pillar holding | maintenance part 11 is formed with stainless steel.

  FIG. 4 shows an upper side surface of the support column holder 11. As shown in FIG. 4, the earth and sand cleaning portion 17 can be formed in a scoop shape by cutting out the upper side of the support column holding portion 11 with a curved surface 18 as shown in FIG.

  As shown in FIG. 5, a connecting bolt 19 is provided so as to penetrate the support column holding part 11 and the underground introduction part 10. The connecting bolt 19 is made of steel. The connecting bolt 19 is inserted through a bolt through hole provided in the bottom portion 16 of the support column holding portion 11 and through a bolt through hole provided in the bottom portion 14 of the underground introduction portion 10.

  The upper side of the connecting bolt 19 is fixed with two washers-provided nuts 20 and 21 provided so as to sandwich the bottom 16 of the support column holding part 11 from above and below. The lower side of the connecting bolt 19 is fixed by two nuts 22 and 23 provided so as to sandwich the bottom 14 of the underground introduction part 10 from above and below. In addition, rubber packings 24 and 25 are interposed between the washers-equipped nuts 20 and 21 and the bottom portion 16 of the support holder 11. Since the rubber packings 24 and 25 are insulative, the connection bolt 19 and the support holder 11 are insulated.

  The lower side of the connecting bolt 19 extends downward through the bottom portion 14 of the underground introduction portion 10, and the ground wire attachment portion 26 is screwed. The ground wire attachment portion 26 is formed in a rod shape, a flange 27 is formed at the upper end, and the lower side is in a wedge shape. The ground wire attachment portion 26 is formed of hexagonal steel material to increase the surface area, and further, the surface is subjected to body plating or carbon coating to reduce the ground resistance. The periphery of the connecting bolt 19 is protected by a vinyl tube B.

  The ground wire 8 is attached so as to be sandwiched between the flange 27 of the ground wire attachment portion 26 and the washer 28 of the nut 23.

  Next, the operation will be described. First, as shown in FIGS. 3 and 5, the tip fixture 5 is attached to the lower end of the column 9. In this case, as shown in FIG. 5, the support column holder 11 is pushed into the lower end of the support column 9 from below the support column 9. The support column holder 11 is pushed into the support column 9 so as to push the lower end of the support column 9 from the inner side toward the outer side, so that the support column holding unit 11 contacts the inner surface of the support column 9 by a spring force. The lower side of the column 9 is elastically and strongly held by the column holding part 11. Thereby, the assembly of the pull-in pole 1 is completed.

  Next, as shown in FIGS. 3 and 5, the lower end of the ground wire 8 is attached so as to be sandwiched between the ground wire attachment portion 26 and the washer 28.

  Next, a hole with a depth of about 1 meter to 1.5 meters is dug in the land where the lead pole 1 is erected. Next, as shown in FIG. 1, the pull-in pole 1 was erected by inserting the lower end side of the pull-in pole 1 into the hole and raising the pull-in pole 1 and then backfilling the hole. Stand up in state. At this time, the upper end of the ground wire 8 is exposed to the ground.

  Next, the switchboard 3 is attached to the pull-in pole 1 with a belt 29. Then, the ground wire 8 is connected to a grounded outlet or a ground terminal of the switchboard 3.

Incidentally, the ground wire 8 is connected to a ground wire mounting portion 26 provided at the tip of the support column 9 as shown in FIGS. Since the support 9 has a considerable weight of about 23 kg to 28 kg, the ground wire mounting portion 26 is strongly pressed against the earth and sand by the large weight of the support 9, and the ground 9 The ground wire attachment portion 26 comes into close contact with the surrounding earth and sand without generating a gap between the wire attachment portion 26 and the surrounding earth and sand. Further, since the ground is always moderately wet at a position of about 1 meter to 1.5 meters from the ground surface, the grounding resistance of the ground wire attachment portion 26 can be reduced also in this respect. As a result, the ground resistance is reduced.
As a result of experiments conducted by the applicant, it was confirmed that the ground resistance was 500Ω or less.

  As described above, in a state where the grounding resistance is reduced, as shown in FIG. 1, after drawing the power line 6, the cord of the construction electric appliance is connected to the switchboard 3, thereby supplying electric power to the electric appliance. Supply and execute construction.

  Then, when the construction is completed, the temporary pull-in pole 1 is removed. In this case, after the temporary pull-in pole 1 is dug out on the ground, the column 9 is pulled out from the tip fitting 5 as shown in FIG. As a result, the tip fitting 5 and the support 9 are separated. After that, holding the tip fitting 5 in the hand, the soil and sand cleaning part 17 of the tip fitting 5 scrapes off the soil, sand, mud, etc. attached to the surface of the column 9, and prepares for the next use. The support 9 is accommodated.

  Further, since the lower end of the support column 9 is covered with the cup-shaped underground introduction part 10, when the support column 9 is driven into the ground, soil, sand, mud or the like does not enter the support column 9. .

  In the first embodiment, the ground wire 8 is connected to the ground wire mounting portion 26. However, as shown by a one-dot chain line in FIG. It is also possible to connect to a part. In this case, since the ground wire 8 is connected to the upper end of the connecting bolt 19 through the support column 9, a pipe P (shown in FIGS. 1 and 2) for protecting the ground wire 8 is not necessary.

  FIG. 6 shows a second embodiment. Compared with the first embodiment, the feature of the second embodiment is that the tip fitting 5 includes only the underground introduction portion 10 and the support holder 11 and the spacer 12 shown in FIGS. 1 to 5. There is no point.

  The pull-in pole 1 according to the first embodiment shown in FIGS. 1 to 5 is used for temporary installation, whereas the pull-in pole 1 according to the second embodiment is used for permanent installation. In the second embodiment as well, the ground wire 8 can be connected to the upper end portion of the connecting bolt 19 in the underground introduction portion 10 as shown by a one-dot chain line in FIG.

  In addition, although the said embodiment demonstrated the case where it applied to a power line as a lead-in line, applying to a communication line as a lead-in line is also possible.

FIG. 1 is an external view of the ground portion of the pull-in pole. (First embodiment) FIG. 2 is a diagram illustrating a state in which the pull-in pole is erected. (First embodiment) FIG. 3 shows a perspective view of a tip fitting provided at the lower end of the retracting pole. (First embodiment) FIG. 4 is a right side view of FIG. (First embodiment) FIG. 5 is a sectional view taken along line AA in FIG. (First embodiment) FIG. 6 shows a second embodiment. (Second Embodiment) FIG. 7 is an external view of the ground portion of the pull-in pole of the background art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lead pole 3 Distribution board 5 Tip fixture 6 Lead wire 8 Ground wire 9 Strut 10 Underground introduction part 11 Strut holding part 19 Connection bolt 26 Ground wire attachment part

Claims (6)

A pull-in pole for pulling in the lead-in wire,
A pipe-shaped column and a cup-shaped underground introduction part that covers the lower end of the column from below,
The lead-in pole, wherein the underground introduction portion includes a ground wire attachment portion, and a ground wire is attached to the ground wire attachment portion.   The pull-in pole according to claim 1, wherein the ground wire attachment portion is formed in a protrusion shape protruding in a wedge shape downward from a lower end of the underground introduction portion.   The underground introduction part is provided with a column holding part to be inserted into the column from below, and the column holding unit is detachably inserted into the column from below to support the column holding unit in the column. The retractable pole according to claim 1 or 2, wherein the retractable pole is held elastically.   4. The retractable pole according to claim 1, wherein an upper portion of the support column holding portion is a scoop-shaped earth and sand cleaning portion. 5.   The lead-in pole according to any one of claims 1 to 4, wherein the lead-in line is a power line or a communication line.   The lead-in pole according to any one of claims 1 to 5, wherein the ground wire mounting portion is embedded at a depth of about 1 to 1.5 meters.

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