JP3316280B2 - Cable junction box - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a cable connection box used for a connection portion of an optical fiber cable or the like.

[0002]

2. Description of the Related Art It is necessary to prevent water or moisture from entering a connection portion such as an optical fiber cable. Therefore, the cable connection portion is protected by using a cable connection box (closure) having a sealing function. Since the cable connection box needs to be openable and closable for reconnection, a mechanical seal that can be mechanically assembled and has good workability is mainly used. FIG. 3A shows a conventional mechanical seal type, for example, a cable connection box of a band fastening type.
It has the structure shown in FIG. This cable junction box
The two half sleeves 1 are formed in a box having a substantially quadrangular cross section in which the two half sleeves 1 are opposed to each other at a side end cross section. The two half sleeves 1 have a packing groove on both side end cross sections, and are fastened by a metal band 3 via the packing 2 to form a watertight and airtight box. 4 is a band fastener.

[0003]

However, the above-mentioned cable connection box has the following problems. That is,
When the band 3 is fastened, the band 3 tries to become circular,
In order to apply pressure to the side of the sleeve, the substantially square box cross section is depressed on both sides as shown in FIG. Because only force can be applied, between A and B, C
-D tends to swell and become circular. As a result, as shown in FIG. 4, the packing 2 at the seam of the half sleeve 1 did not function sufficiently, and there was a risk of gas leak. Therefore, when the thickness of the half sleeve is increased to increase the rigidity in order to suppress the deformation of the half sleeve, there is a problem that the weight of the box increases.

[0004]

SUMMARY OF THE INVENTION The present invention provides a cable junction box which solves the above-mentioned problems, and has a substantially rectangular cross section and is divided into two in the longitudinal direction of the cable. In the cable connection box, the seam of the half sleeve is opposite
Is located at the center of the side where
Intervening, and the band fastening part is adjacent to the seam
It provided so as to face the substantially near the center between the-half the van <br/> de fastening portion on the circumference of the sleeve, convex particle previous
Interposed between the serial-half sleeve and the band, the fastening bands and the first invention to press the half-split sleeve with the convex-like material, the that in the invention, and the convex particle provided in the band 2 invention. In the cable junction box having the above-mentioned structure, the band directly presses the half sleeve at the four corners during the process of tightening the half sleeve with the band at the time of assembling the sleeve, and the half split via the convex object Since the sleeve is pressed from the outside to the inside, the half-split sleeve does not bulge outward and the cross section of the box does not deform into a circle. Therefore, even if the half sleeve is fastened with a band, the packing of the joint of the half sleeve sufficiently functions, and water tightness and air tightness can be secured. In addition, the present invention is applied to a sleeve having a substantially square cross section, but the meaning of the substantially square shape means that when the band is fastened, the band applies pressure to the four corners of the sleeve, and a substantially central portion of the half sleeve is provided. In order not to apply a pressure, the half sleeve is shaped to bulge outward.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is an explanatory sectional view of one embodiment of a cable connection box according to the present invention. In this embodiment, a pair of half sleeves 11 , 11 each of which is a half square tube made of fiber reinforced polypropylene is combined, and a stainless steel band 12 is joined to the half sleeve 11.
It is fastened so as to be located adjacent to the seam . The band 12 is provided with a projection 13 at a position substantially at the center on the circumference of the half sleeve 11. 14
Is a packing interposed at the seam of the half sleeve 11 , and 15 is a band fastener. FIG. 2 (a), (b)
FIG. 2 is a front view and a side view of the band in a fastened state. The band 12 presses the half-split sleeve 11 inward with the convex 13 so as to prevent the half-split sleeve 11 from expanding outward and becoming circular. In addition, the convex object is not always provided on the side of the band facing the half sleeve, and may be simply interposed between the band and the circumference of the half sleeve. Further, the shape of the half sleeve is not limited to the above embodiment, and it goes without saying that a half ellipse may be used.

[0006]

According to the present invention as described in the foregoing, cross-section a substantially rectangular, in the cable connection box has signed a halved sleeve which is bisected in the longitudinal direction of the cable band, the-half The joint of the sleeve is of cross section
Located at the center of the opposite side, packing
And the band fastening part is adjacent to the joint
And it provided, as opposed to the vicinity of substantially the center between the <br/> band fastening portion on the circumference of the semi-split sleeve, convex particle
Fear There interposed between said half-split sleeve and the band, because the fastening bands to press the half-split sleeve with the convex-like material, seam packing half sleeve to play a fully functional, causing gas leakage There is no good effect.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a cable connection box according to the present invention.

FIGS. 2 (a) and 2 (b) are a front view and a side view, respectively, of a band in the above embodiment in a fastened state.

FIGS. 3A and 3B are a side view and a cross-sectional view of a conventional cable junction box, respectively.

FIG. 4 is an explanatory diagram of a problem of a conventional cable junction box.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Half sleeve 12 Band 13 Convex object 14 Packing 15 Band fastener

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-53907 (JP, A) JP-A-6-59802 (JP, U) JP-A-2-33532 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) G02B 6/00 G02B 6/24 H02G 15/10 H02G 3/08

Claims (2)

(57) [Claims] 1. A cable connection box having a substantially rectangular cross section and a half-split sleeve divided in the longitudinal direction of a cable and fastened with a band, the joining of the half-split sleeves.
The seam is located at the center of the opposite side of the cross section.
Packing is interposed at the eye, and the band fastening part is
The serial seam disposed adjacent, to face the vicinity of substantially the center between the peripheral on the band fastening portion of the half-split sleeve
So that the convex is between the half sleeve and the band
Cable junction box interposed, the fastening bands is characterized in that for pressing the half-split sleeve with the convex thereof. 2. The cable connection box according to claim 1, wherein a convex member is provided on the band.