JP2596345Y2 - High frequency cable support structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for supporting a high frequency cable connected to a micro line or various communication and broadcasting antennas on a structure such as a steel tower.

[0002]

2. Description of the Related Art Conventionally, as a structure for supporting a high-frequency cable on an outdoor structure, a structure using a support fitting 3 as shown in FIG. 5 is generally employed.

The supporting bracket 3 includes a pair of Ω-shaped clamping members 5 for clamping the high-frequency cable 1 formed as a coaxial cable over substantially the entire circumference from both front and rear sides, and a structure (for example, a steel tower) And a pair of left and right bolts 6 fixed to the horizontal rail 2a or the like of the ladder 2. The high-frequency cable 1 is sandwiched between the sandwiching members 5 via the cushioning material 7 and tightened up and down with the nut 8 from the front and rear. It is supposed to.

[0004] A relatively short predetermined interval (for example, 1.
0 to 1.5 m) so that the long high-frequency cable 1 is firmly supported along the outer surface of the structure.

[0005] In FIG. 5, two bolts 6 are used.
The case where two high-frequency cables 1 are arranged side by side is shown.

[0006]

By the way, if the above-mentioned support fitting 3 is used, a sufficient gripping force can be obtained in supporting the load of the high-frequency cable 1, but the number of components is large and expensive. At the same time, there are many fastening operation points at the time of assembling, and it takes time and effort. In addition, conventionally, since the support fitting 3 is used for all the cable support locations,
There was a problem that the cost of the equipment increased considerably.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to solve such a problem of the conventional support structure.

Therefore, the support structure for a high-frequency cable according to the present invention includes a support member for supporting the weight of the high-frequency cable and a vibration stopper for suppressing vibration of the cable. The support member is provided at a predetermined interval, and the vibration stopper is provided at a predetermined interval. The support fittings are arranged and fixed on the outer surface of the structure at shorter intervals than the support fittings, and the support fittings are a pair of holding members for holding the high-frequency cable from both sides over substantially the entire circumference, and bolts for fixing the two holding members. And the nut, while the vibration stopper is a flat plate fixed with bolts.
And a substantially U-shaped contact portion extending from the fixed portion and extending along a part of the outer periphery of the high-frequency cable are formed in series.
And the opening for inserting the cable at the abutting portion is at the front.
It is provided so as to face a plane including the fixing portion.

[0009]

Considering the supporting strength when a high-frequency cable is supported outdoors, for example, when wind pressure acts on a cable supported at two points above and below, the maximum bending moment Mmax acting on the supporting point is Mmax = P · l ² / 12 (1) where l is the cable support interval, P = cqa. Where c
Wind coefficient, q is the rate pressure ^{(= v 2/16, v} ; wind speed), a is the wind area.

On the other hand, the relationship between the bending moment Mmax ′ and the allowable vibration strain εy is as follows: Mmax ′ = π · dm ² · t · E · εy / 4 (2) where dm is the average outer diameter of the outer conductor of the cable. , T is the average thickness of the outer conductor of the cable, and E is the Young's modulus of the cable.

From the above equations (1) and (2), the support interval which does not cause vibration fatigue fracture, that is, the support interval lmax satisfying Mmax ≦ Mmax 'is as follows.

[0012]

(Equation 1)

Accordingly, for example, when the cable is a coaxial cable equivalent to 39D, dm = 46 mm, t = 1.5 mm,
Allowable vibration strain E · εy = 1.3, wind speed v = 60 m / sec (P = 1
5 kg / m), lmax ≦ 1.6 m.

On the other hand, the maximum support interval lmax 'necessary only to support the cable's own weight is given by: lmax' ≦ if the weight per unit length of the cable is w and the support force per support point is p. p / w (4) where w = 1.9 kg / m, p
= 25 kg, lmax '≤ 13 m.

That is, in order to support the weight of the high-frequency cable, it is sufficient to provide a support point every 13 m.
On the other hand, in order to prevent wind pressure vibrations, it is sufficient to provide a cable anti-sway means at intervals of about 1.6 m between these support points.

In view of the above, the present invention uses a supporting bracket using a pair of holding members at a portion corresponding to the cable weight supporting point, and uses a supporting bracket at a part of the outer periphery of the cable at the steady rest supporting point. By using a simple vibration stop fitting that comes into contact, a desired cable support function and vibration stop function are exhibited.

[0017]

FIG. 1 shows a schematic configuration of a case where a high-frequency cable 1 is disposed and supported along an outer surface of a structure 2 such as an antenna tower. The high-frequency cable 1 includes a support fitting 3 and a vibration-stopping fitting. 4 and supported on the structure 2.

As shown in FIG. 2, the support 3 is the same as the support 3 conventionally used.
A pair of Ω-shaped holding members 5 for holding the high-frequency cable 1 over substantially the entire circumference from both front and rear sides, a pair of left and right bolts 6 for fixing the both holding members 5 to the horizontal rail 2 a of the structure 2, and the like. The high-frequency cable 1 is composed of a cushion member 7 and a nut 8 provided inside,
Then, it is sandwiched between the cushion members 7 and is fastened and fixed with nuts 8 from front and rear.

As shown in FIG. 2, the vibration stopper 4 has a flat fixing portion 4a which is fixed to the cross bar 2a of the structure 2 via one bolt 9 and nut 10. This fixed
Extending from one end of the tough by the contact portion 4b of the substantially U-shaped along the part of the outer periphery of the high frequency cable 1 is formed into a series, or
The opening for inserting the cable into the contact part 4b is fixed to the fixing part 4a.
Are provided so as to oppose a plane including. And
The cushion material 11 is attached to the inner surface of the contact portion 4b.
You. Thus, the opening for inserting the cable in the contact portion 4b is
If facing the plane including the fixing part 4a, the high-frequency cable
Even if excessive vibration is applied to cable 1, cable 1
From the vibration stopper 4 and jump out
Is prevented.

More specifically, for example, the support fittings 3 are installed at intervals of 5 to 7.5 m, and the vibration stopping fittings 4 are installed at intervals of 1.0 to 1.5 m.

As the vibration stopper 4, for example,
As shown in FIGS. 3 and 4, the abutment portion 4b is formed in a U-shape, and a fixing portion 4a having a locking concave portion 12 for locking the horizontal beam 2a is provided at both ends of the leg portion, and fixed to the horizontal beam 2a. The part 4a is hooked and the locking bolt 13 is screwed into the screw hole 14 of the fixing part 4a.
It is good also as composition screwed to. In this case, it is not necessary to form a hole in the cross rail 2a. Further, in this embodiment, two high-frequency cables 1 can be supported as shown by phantom lines in FIG.

[0022]

According to the present invention, by introducing a vibration-stopping bracket having a simple structure, a small number of components, and easy handling, the cable support strength and the vibration-stopping function can be reduced without increasing the cost. It is possible to reduce the number of supporting brackets that require time and effort for mounting to a fraction of the conventional number. Therefore, it has become possible to reduce the cost of the support member and the number of man-hours for mounting work as a whole.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing a part of a cable support structure according to an embodiment of the present invention.

FIG. 2 is a perspective view of a main part of FIG.

FIG. 3 is a perspective view showing another embodiment of the vibration stopper.

FIG. 4 is a partially cutaway side view showing a mounted state of a vibration stopper.

FIG. 5 is a perspective view of a main part of a conventional structure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High frequency cable, 2 ... Structure, 3 ... Support bracket, 4 ...
Vibration stoppers, 4a: fixed part, 4b: contact part, 5: clamping member, 6: bolt, 8: nut.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Eiichi Fujimura 1008 Niibori, Kumagaya-shi, Saitama Mitsubishi Cable Industry Co., Ltd. Kumagaya Works (72) Inventor Hirozo Okuzone 4-chome Ikejiri, Itami-shi, Hyogo Mitsubishi Electric Line Inside Itami Works, Ltd. (72) Inventor Kiyohiro Omatsuzawa 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Ryoji Morimoto 1-1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Japan Inside Telegraph and Telephone Co., Ltd. (56) References Japanese Utility Model Sho 63-198331 (JP, U) Japanese Utility Model Sho 54-24697 (JP, U) Japanese Utility Model Sho 48-27389 (JP, U) Japanese Utility Model Utility Model 55-173236 (JP, U) JP, U) Japanese Utility Model Showa 60-44423 (JP, U) Japanese Utility Model Showa 62-14926 (JP, U) Japanese Utility Model Showa 63-155104 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , (DB name) H02G 7/00-7/22

Claims (1)

(57) [Scope of request for utility model registration] 1. A support structure for fixedly supporting a high-frequency cable along an outer surface of a structure, comprising: a support bracket for supporting the weight of the high-frequency cable; and a vibration-stopping bracket for suppressing vibration of the cable. The metal fittings are arranged at predetermined intervals, the vibration-stopping metal pieces are arranged and fixed on the outer surface of the structure at shorter intervals than the supporting metal fittings, and the supporting metal fittings sandwich a high-frequency cable from both sides over substantially the entire circumference. And the vibration-stopping member is a flat plate-shaped fixing portion fixed with bolts, and is extended from the fixing portion. A substantially U-shaped contact portion along a part of the outer periphery of the high-frequency cable is formed in a series.
And the opening for inserting the cable in the contact portion is
A support structure for a high-frequency cable, which is provided so as to face a plane including a fixing portion .