JPH11205976A - Steel tower wiring communication cable therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain reduction in construction cost, maintenance of surrounding landscape, improvement of stirring work efficiency and degradation prevention for communication cables, and prevention of generating wind noise. SOLUTION: A tower body 1 consists of a hollow body with a plurality of steel pipes 2 or 6 connected. Their outer periphery surfaces 2A,... 6A are formed into smooth surfaces, a top opening part 10 is formed at the steel pipe 6 of the uppermost end, and a bottom opening part 11 is formed at the steel pipe 2 of the lowermost end. In the tower body 1, an upper side wire support body 12 is fixed in the vicinity of the top opening part 10, and a lower side wire support body 13 is fixed in the vicinity of the bottom opening part 11. Guard wires 14A-14D are stringed between the upper side wire support body 12 and the lower side wire support body 13, and communication cables 16, 17, and 18 are supported by the guide wires 14 through cable retaining bodies 15, 15,....

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication cable for suspending a communication cable connected between a tower communication device installed on an upper end side of a tower body and a ground communication device installed on the ground. Related to a fixed-type steel tower.

[0002]

2. Description of the Related Art Conventionally, steel towers or pillars for suspending communication cables for connecting communication equipment installed on the upper end side of a tower body with communication equipment installed on the ground include concrete iron pillars and hollow type steel towers. There are steel towers and angle-type iron poles. Concrete-type iron poles and angle-type iron poles have a structure in which communication cables are suspended in an externally exposed state, and hollow steel towers include a communication cable externally exposed type and an internal type.

[0003]

Among the above-mentioned prior arts, in the case of a steel tower or a steel pole that is externally exposed to a communication cable, a wind noise is generated by the exposed communication cable, which may cause environmental problems. However, there are disadvantages that the communication cable is easily deteriorated and that it is harmed by birds. In addition, metal fittings that are exposed to support the communication cable are easily deteriorated, have a poor appearance, and cause wind noise. On the other hand, telecommunication cable built-in towers are large and heavy because they have a large diameter so that workers can work inside the tower, requiring large heavy equipment for construction. However, there are drawbacks such as an increase in the cost of construction of the tower, a large site for the construction, and a sense of incongruity and intimidation in the surrounding area. In addition, there is a disadvantage that the work efficiency is poor because the work of installing the communication cable in a narrow tower is performed.

[0004] On the other hand, the ladder conventionally installed on the tower is a fixed ladder fixed to the outer surface of the tower, so that it is exposed to the outdoors for a long period of time and has a drawback that it rusts and its strength is reduced. Therefore, there is a problem that the maintenance cost is increased and it is necessary to replace the battery after using it for a long time. Also,
There are problems that the aesthetic appearance of the tower body and the surrounding scenery are impaired, and that it also becomes a source of wind noise.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and can reduce the construction cost, eliminate the damage to the surrounding scenery, and efficiently hang the communication cable. In addition, to provide a telecommunication cable built-in tower capable of preventing deterioration of the communication cable and generation of wind noise due to external factors, and generation of wind noise and reduction in strength due to being detachable from the tower body. It is an object of the present invention to provide a communication cable built-in tower having a detachable ladder that can be used for a tower body whose outer diameter changes in the height direction without having the problem.

[0006]

Means of the present invention configured to solve the above-mentioned problems are provided in a communication cable which is erected on the ground and hangs a communication cable from an upper end to a lower end inside the communication cable. A hollow steel tower formed by connecting a plurality of cylindrical portions having smooth outer peripheral surfaces, an upper opening formed at an upper end side of the tower body, and a lower end side of the tower body. A lower opening, a wire support provided at an upper end side and a lower end side of the inside of the tower, a guide wire stretched between the upper and lower wire supports to support a communication cable, and the guide wire And a cable holder for holding the communication cable.

[0007] A detachable ladder, which is configured to be extendable and contractable and has a plurality of arms provided with engaging members at the ends thereof, protruding from the ladder main body, is provided on the outer peripheral surface of the tower at predetermined intervals in the height direction. By attaching to the tower body by detachably engaging with a plurality of locking bodies fixed by the above, the ladder can be detachably installed on the tower body having an outer diameter different in the height direction. And
The problem of wind noise can be eliminated.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawing, reference numeral 1 denotes a tower body erected on the ground G via a foundation block A. The tower body 1 is formed by sequentially connecting a plurality of steel pipes 2, 3, 4, 5, and 6 with bolts and nuts. It is made of something that is closed. here,
Each of the steel pipes 2, 3, 4, 5, 6 has an outer peripheral surface 2A, 3A,
4A, 5A, and 6A are formed smoothly, and flanges 2B, 2C, 3B, 3C, 4B, 4C, 5
B, 5C, and 6B are formed of a hollow body, and the lower steel pipe 2 (3, 4, 5, 5) and the upper steel pipe 3
By sequentially reducing the diameter of (4, 5, 6), the entire tower 1 is tapered from the lower end to the upper end. And the platform 7, safety fence 8,
And a pair of cable outlet pipes 9, 9 communicating with the inside of the steel pipe 6, respectively.

Reference numeral 10 denotes an upper opening formed in the uppermost steel pipe 6, and the upper opening 10 can be opened and closed by a lid (not shown). Reference numeral 11 denotes a lower opening formed in the lowermost steel pipe 2. The lower opening 11 can also be opened and closed by a lid (not shown). An upper wire support 12 is located near the upper opening 10 and fixed in the steel pipe 6 by welding means. A reference numeral 13 is located near the lower opening 11 and fixed in the steel pipe 2 by welding means. The lower wire supports, each of which has an annular mounting plate 12A (13A).
A support cylinder 12B (13B) protruding from the inner peripheral edge of the annular mounting plate 12A (13A); and a support cylinder 12B (13
B) A plurality of locking holes 12C formed in the circumferential direction and spaced apart from each other.
(13C).

Reference numeral 14 denotes communication cables 16, 17,
A guide wire stretched between the upper wire support 12 and the lower wire support 13 to support the wire 18, the guide wire 14 is connected to the wire main body 14A and the upper end side of the wire main body 14A. A carabiner 14B detachable from the upper wire support 12, a turnbuckle 14C connected to the lower end of the wire body 14A, and a shackle 14D connected to the turnbuckle 14C. By adjusting, the guide wire 14 can be stretched with a desired tension.

Reference numerals 15, 15,... Denote cable holders for supporting the three communication cables 16, 17, 18 on the guide wire 14. The cable holder 15 has a pair of holding pieces 15A, 15A that can be integrated with bolts and nuts while holding the guide wire 14, and communication cables 16, 17, and a pair of holding pieces 15A, 15A.
A pair of tightening bands 15B, 15B for tightening 18 are used by being mounted on the guide wire 14 at predetermined intervals. The communication cable held by the cable holder 15 is a pair of fastening bands 15B,
By fastening at 15B, it is possible to cope with a change in the number of communication cables. Then, by using the cable holder 15 of the present embodiment, one guide wire 14 can support a plurality of desired communication cables.

Reference numerals 16, 17, and 18 denote three communication cables supported by the guide wires 14 by the cable holders 15 and suspended between the upper end and the lower end of the tower 1. The upper ends of the communication cables 16, 17, 18 are led out from the cable outlet pipe 9 or the upper opening 10, and are provided on the tower-side communication device 19 installed on the platform 7 or the transmission body provided on the tower 1. It is connected to antennas 19A, 19A. Further, the lower end side is led out from the lower opening 11 and is connected to a terrestrial communication device 20 which is located near the tower body 1 and installed on the ground G.

Reference numeral 21 denotes a detachable ladder made of aluminum for elevating and lowering the tower 1. The detachable ladder 21 includes a pair of columns 22, 22 set to a predetermined length, and the columns 2, 22.
Plural step materials 2 erected at predetermined intervals between 2 and 22
, 23,..., And two sets of arms 24, 24, 24, 24, each of which is a pair of two protruding laterally from upper and lower sides at predetermined intervals on each support 22, An engagement pin 25 is fixed to the tip of each arm 24.

Here, each arm 24 is fixed to the column 22 and protrudes in the lateral direction, and has a plurality of fixed arm members 24A having a plurality of bolt holes formed in the longitudinal direction. And a movable arm member 24B having a bolt hole of the same pitch as the fixed arm member 24A.
By fastening the movable arm member 24B to the fixed arm member 24A with a bolt / nut inserted into the bolt hole of B, the arm body 24 can expand and contract. The detachable ladder 21 having the above-described configuration is a lightweight body that can be carried by an operator.

On the other hand, reference numerals 26, 26,... Denote locking cylinders for detachably locking the detachable ladder 1 to the tower body 1. The locking cylinders 26 are steel pipes 2, 3, 4,. 5 and 6 outer peripheral surfaces 2A,
3A, 4A, 5A, and 6A are fixed in pairs in the height direction of the tower body 1 at the same interval as the arm body 24 and in the circumferential direction with a welding means. Therefore, each steel pipe 2, 3, 4,
The engaging pins 25 of the detachable ladders 21, 21,... Are engaged with the locking cylinders 26, 26,. . Can be connected in series.

This embodiment has the above-described configuration. Next, a procedure for suspending the communication cables 16, 17, and 18 in the tower 1 will be described. First, detachable ladders 21, 21,... Are sequentially mounted on the tower 1 from the lower end to the upper end by lifting the work by themselves or using heavy equipment such as a crane truck. And the platform 7 are communicated by detachable ladders 21, 21,.... In this case, since each detachable ladder 21 is configured so that the arm portion 24 can be extended and contracted, the diameter is sequentially reduced and the flanges 2C, 3B, 3
C, 4B, 4C, 5B, 5C, and 6B can be installed in a state where the entirety is perpendicular to the steel pipes 2, 3, 4, 5, and 6 from which they protrude.

The worker who climbs the platform 7 by the detachable ladder 21 connected to the upper wire support 1
A pulley (not shown) is engaged with the pulley 2, and a lead wire pulled up from the ground G is hung on the pulley, and the lead wire is suspended from the inside of the tower 1 to the ground G side. One end of the lead wire located outside the tower 1 is wound around a winch drum (not shown) installed on the ground G, and the other end of the lead wire inserted inside the tower 1 is a guide wire 14. The communication cables 16, 17 and 18 are supported by the guide wire 14 by the cable holder 15. Thereafter, the guide wire 14 is pulled up in the tower 1 by operating the winch to wind up the lead wire. When the guide wire 14 is pulled up by an appropriate length and the communication cables 16, 17, 18 are also raised,
Further, the communication cable 16, 17, 18 is supported on the guide wire 14 by the cable holder 15, and the guide wire 14 is pulled up again.

When the guide wire 14 reaches the upper opening 10, the carabiner 14B is engaged with the upper wire support 12, and the lead wire is removed. Then, the communication cables 16, 17, and 18 pulled up together with the guide wire 14 are pulled out from the upper opening 10 to make them connectable to the tower communication device 19. On the ground G side, a shackle 14D is engaged with the lower wire support 13, and a turnbuckle 14C guides the shackle 14D.
The communication cables 16, 17, and 18 extending outward from the lower opening 11 are connected to the ground communication device 20 so that the communication cables extend from the upper end to the lower end in the tower 1. 16, 17, 18 can be suspended. When the above operation is completed, the worker removes the detachable ladders 21, 21,... From the tower 1 by himself or by using a heavy machine such as a crane truck.

In this embodiment, three communication cables 16, 17, and 18 are supported by one guide wire 14. However, more communication cables may be supported in consideration of the thickness of the communication cable. Good thing.

The cable holder 15 is not limited to the one shown in the present embodiment, but is
A structure that can be locked to the guide wire 14 by applying its own weight of 6, 17, and 18 may be used.

As described above, according to the present embodiment, the communication cables 16, 17, and 18 are connected to the plurality of cable holders 15,
.. Are supported by the guide wire 14, the phenomenon that the communication cables 16, 17, and 18 are loosened or broken by their own weight can be reliably prevented.

[0022]

The present invention has the following advantages because it is constructed as described above. (1) It is sufficient for the tower to have an inner diameter in which a guide wire and a communication cable can be installed, and it is not necessary to have an inner diameter in which a worker can enter. Therefore, the tower can be configured in a thin shape. The weight can be reduced, the construction cost can be reduced, and the site area for installation is minimal. In addition, it does not give a sense of incongruity or intimidation to the surroundings, and can avoid damage to the landscape. (2) Since the communication cable is configured to be supported by the guide wire via the cable holder, it is possible to reliably prevent the communication cable from being loosened or broken by its own weight. (3) The work of suspending the communication cable can be performed on the ground and on the upper end side of the tower, and it is not necessary to perform the work inside the tower. (4) Because the communication cable is installed inside the tower,
The communication cable can be prevented from deteriorating due to external factors such as rainwater, freezing and temperature change, and can be protected from bird damage. (5) Since the outer peripheral surface of the tower body is smooth, the generation of wind noise can be reduced as much as possible, and the situation where the surrounding environment is damaged by noise can be eliminated. (6) Since the detachable ladder is configured so that the arm body can be extended and contracted, it can be installed on a tower body having a different diameter in the height direction or an overhanging flange, and only one ladder is used. Since there are enough types, equipment costs can be reduced and work efficiency can be improved. (7) The detachable ladder is configured to be detachable from the tower so that it can be removed except during work, so that the problem of early deterioration due to the ladder being exposed to the weather can be eliminated, and there is no wind noise caused by the ladder. Can be installed as a tower.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a communication cable built-in steel tower according to an embodiment of the present invention.

FIG. 2 is an enlarged half sectional view showing a main part of an upper end side and a lower end side of a steel tower.

FIG. 3 is an external perspective view of a cable holder.

FIG. 4 is an explanatory view showing a part of a tower body and a detachable ladder.

FIG. 5 is a partially enlarged view of a state where a detachable ladder is attached to a tower body.

FIG. 6 is a plan view showing a tower body to which a detachable ladder is engaged, which is cut at an intermediate position.

[Explanation of symbols]

 1 Tower 2, 3, 4, 5, 6 Steel Pipe 10 Upper Opening 11 Lower Opening 12 Upper Wire Support 13 Lower Wire Support 14 Guide Wire 15 Cable Holder 16, 17, 18 Communication Cable 21 Detachable Ladder 24 Arm 25 Engagement pin (engagement body) 26 Locking cylinder (locking body)

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takeshi Shirakata 3-1, Kita 3-Jo Nishi, Chuo-ku, Sapporo, Hokkaido 5 NTT Hokkaido Mobile Communication Network Co., Ltd. (72) Inventor Dr. Fujita Hokkaido 5-3-1-1, Kita 3-Jo Nishi, Chuo-ku, Sapporo-shi NTT Mobile Communications Network Co., Ltd. (72) Inventor Masami Hayashi 7-3-1, Odori-nishi, Chuo-ku, Sapporo, Hokkaido NTT Corporation・ In the facility of Hokkaido Branch (72) Masayuki Hayashi 7-3-1, Odori Nishi, Chuo-ku, Sapporo, Hokkaido, Japan In the facility of NTT Facility Corporation Hokkaido Branch (72) Kazuki Nakamura Sapporo, Hokkaido 7-3 Odori Nishi 1-chome, Chuo-ku NTT Facility Corporation Hokkaido Branch

Claims (2)

[Claims] 1. A communication cable built-in type tower that is erected on the ground and hangs a communication cable from an upper end side to a lower end side of the inside, and is formed by connecting a plurality of cylindrical portions having smooth outer peripheral surfaces. A hollow tower body, an upper opening formed at an upper end side of the tower body, a lower opening formed at a lower end side of the tower body, and wire supports provided at an upper end side and a lower end side of the tower body, respectively. Body and
A guide wire extending between the upper and lower wire supports to support a communication cable; and a cable holder attached to the guide wire at a predetermined interval and holding the communication cable. Characterized by a telecommunication cable built-in tower. 2. A detachable ladder comprising a plurality of arms which are configured to be extendable and contractable, and are provided with an engaging body at the tip thereof, are spaced apart in the longitudinal direction of the ladder main body and project laterally. 2. The telecommunication cable internal type tower according to claim 1, wherein said tower is configured to be attached to said tower body by detachably engaging with a plurality of locking bodies fixed to the outer surface at predetermined intervals in a height direction.