JPS6218885B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a mechanical strength maintaining section in an optical cable jacket connection section.

(Prior art) Conventionally, this type of mechanical strength retaining part has been developed by patent application 1983-
170828, it is composed of the internal fitting shown in Fig. 1, the gripping spacer shown in Fig. 2, and the external fitting shown in Fig. 3 that accommodates the gripping spacer, and when making a branch connection, the fitting shown in Fig. 4. As shown in Figure 2, three types of external fittings and the parts shown in Figures 1 and 2 were used in combination.

In this holding part, in response to variations in the cable outer diameter, the internal metal fittings shown in FIG. 1 and the gripping spacers shown in FIG. 2 are replaced as appropriate, and the external metal fittings are used in common.

However, the gripping spacer has a special shape with protrusions of 1.5 mm in height scattered around, and the wall thickness must be changed depending on the cable, so it has to rely on cutting, etc., making it expensive. Moreover, the external metal fitting shown in FIG. 3 also requires a groove to suppress the back and forth movement of the gripping spacer, and has the drawback that a significant reduction in price cannot be expected due to its structure.

In addition, the method of fixing the tension member is to fix the tension member with metal fittings in such a way that it runs vertically across the front of the cable, which has the disadvantage of complicating the work of organizing the fibers coming out of the cable and connecting the core wires. It was hot.

(Objective of the Invention) In order to eliminate these drawbacks, the object of the present invention is to simplify parts, reduce the cost by reducing the number of parts, and improve workability. The present invention will be explained in detail below with reference to the drawings.

(Structure and operation of the invention) FIG. 5 is a perspective view of an internal fitting used in the invention, which is composed of a semicircular central part 1 and a flat plate part 2 extending radially outward from both ends of the central part 1. , a projection 3 is provided on the outer peripheral surface of the central portion, and a bolt hole 4 is provided in the flat plate portion 2.

FIG. 6 is a perspective view of the external fitting used in the present invention, which is composed of a central part 5 and a flat plate part 6 like the internal fitting, and has a protrusion 7 on the inner circumferential surface of the central part 5.
The flat plate part 6 has a bolt hole 8 at the same position corresponding to the bolt hole 4 of the internal fitting.

FIG. 7 shows a state in which the cable jacket 11 is gripped using the internal fitting 9 of FIG. 5 and the external fitting 10 of FIG. 6.

The applicable cables have large variations in jacket thickness, but the protrusion 7 for the minimum thickness of the jacket
completely bite into the outer cover 11, and at this time, the outer surface of the flat plate part 2 of the internal fitting 9 and the flat plate part 6 of the external fitting 10
If the inner surface of the external fitting 1 is designed so that it is in close contact with the external fitting 1, the
Therefore, the size and height of the protrusions 7 can be reduced to 0.5 to 1.0 mm, and the number of protrusions 7 can be reduced.

As mentioned above, the internal fitting 9 and the external fitting 10
Both have extremely simple shapes and can be manufactured using a press or the like, and the cost of the parts can be significantly reduced.

Further, FIG. 8 shows an embodiment in which the present invention is applied to a branch connection section. In FIG. 8, 13 is a cable (core), 14 is a base metal fitting for fixing the cable grip, and the angle of the line connecting the center of the base metal fitting 14 and the center of the cable core 13 is
It is 120°.

By making the base metal fitting 14 into such a simple shape, processing by extrusion etc. is possible,
Compared to the grip shown in Figure 4, the number of parts is reduced,
It is possible to achieve a significant price reduction.

Changes in the cable outer diameter can be accommodated by appropriately replacing the internal fitting 9 and the external fitting 10, and by using the base fitting 14 shown in Fig. 8, it is possible to change the cable from a straight connection to two branches. This makes it possible to connect various cable diameters up to.

Note that the connection to the other end of the cable can be performed by connecting the centers of the base metal fittings or by connecting the base metal fittings to the connection case.

Optical cables often include a tension member in the center of the cable to reduce the force exerted on the fiber during installation. If this tension member is left disconnected within the connection part, it will protrude or retract due to heat cycles etc., which will adversely affect the fiber, so it is necessary to fix it to the mechanical strength maintaining part.

9, 10, and 11 show a method of fixing tension members, 15 is a tension member, 16 is a metal pipe, 17 is an optical fiber, and 18 is a tension member.
A connecting rod 19 is for fixing the caulked metal pipe 16 and connecting it to the metal fitting 20 protruding from the base metal fitting 14, and 19 is a hole for attaching the caulked metal pipe, and the depth is narrower than the caulked metal pipe and the width is metal. Smaller than the outside diameter of the pipe.

To fix the tension member 15 to the base metal fitting 14, cut the tension member 15 protruding from the cable 13 at a predetermined position, and insert a metal pipe 16 whose inner diameter is slightly larger than the tension member from the cut side. Then, use a tool to caulk the center part of the metal pipe 16 and attach the tension member 15.
Fix it on top. Thereafter, the caulked metal pipe 16 is inserted into the hole of the connecting rod 18 while lowering the connecting rod 18 from above. Insert the metal fitting 20 protruding from the base metal fitting 14 into the hole of the connecting rod, and
The tension member 15 is fixed to the base metal fitting 14 by tightening bolts from the front side of the member 8.

FIG. 11 shows the fixed state seen from the connection side.
Since the connecting rod 18 only extends from the center of the base metal fitting 14 to the vicinity of the tension member 15 with respect to the cable, subsequent cable connection and cable arrangement are easy.

(Effects of the Invention) As explained above, the mechanical strength maintaining part of the present invention not only has a small number of parts constituting the cable gripping part, but also has a simple structure, so it is easy to process and inexpensive.

In addition, by simply tightening the internal and external fittings at the same time, sufficient strength can be reliably obtained without adversely affecting the fiber. By using a base fitting with a simple structure, it is possible to make connections ranging from straight connections to bifurcated connections on one side. Various types of cables can be easily connected.

Furthermore, the method of fixing the tension member improves work efficiency by reducing the number of screws as much as possible, and since the connecting rod only crosses a part of the front of the cable, it is easier to connect the core wires.
It is possible to easily organize the core wires.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional internal fitting, Fig. 2 is a perspective view of a conventional gripping spacer, Fig. 3 is a perspective view of a conventional external fitting, and Fig. 4 is a conventional gripping for branch connection. A perspective view of the metal fitting, FIG. 5 is a perspective view of the internal metal fitting of the present invention, and FIG. 6 is a perspective view of the external metal fitting.
FIG. 7 is a perspective view showing the gripping state, FIG. 8 is a view showing the gripping fitting for branch connection, FIG. 9 is a perspective view showing how the metal pipe is attached to the tension member, and FIG. 10 is the connecting rod. The configuration diagram, FIG. 11, is a diagram showing how the tension member is fixed to the base metal fitting as seen from the connecting portion side. 1...Semicircular center part, 2...Flat plate part of the terminal, 3...
Projection, 4... Bolt hole, 5... Semicircular center, 6...
Terminal flat plate part, 7...Protrusion, 8...Bolt hole, 9...Internal metal fitting, 10...External metal fitting, 11...Cable jacket,
12...Screw, 13...Cable (core), 14...Base metal fitting, 15...Tension member, 16...Metal pipe, 17...Optical fiber, 18...Connecting rod, 19
...Hole for caulking pipe, 20...Metal fitting protruding from base metal fitting.

Claims (1)

[Claims] 1. In the mechanical strength maintaining part of the optical cable jacket connection part, which is tightened by sandwiching the cable jacket that has been torn apart and spread out between the internal metal fitting and the external metal fitting, the internal metal fitting has a semicircular central part with a protrusion on the outer surface and this It consists of a pair of metal fittings consisting of a flat plate part having bolt holes extending radially outward from both ends of the central part, and the external metal fitting has a semicircular central part having a protrusion on the inner circumferential surface, and a flat plate part having bolt holes extending radially outward from both ends of the central part. It consists of a pair of metal fittings consisting of a flat plate part extending in the radial outward direction and having bolt holes at positions corresponding to the bolt holes of the internal fitting. By setting the four flat plate parts of the internal metal fitting and external metal fitting to be in close contact with each other, the protrusion completely bites into the outer cover for cables with various jacket thicknesses, and the inner metal fitting and the external metal fitting are set so that they are in close contact with each other. By attaching three sets of internal and external metal fittings to the base metal fitting, which has a structure that allows the centers of the cables held by the metal fittings to be installed at 120° intervals, it is possible to connect from a straight line to two branches on one side. A metal pipe with an inner diameter larger than the outer diameter of the tension member is placed on the tension member located in the center, and after the pipe is fixed to the tension member by caulking the center part, the caulking part is attached to the terminal part. The caulking part is attached to the hole of the connecting rod, and the connecting rod has a hole at the other end that can be screwed to the metal fitting protruding from the center of the base metal fitting, and the connecting rod protrudes from the base metal fitting. A mechanical strength maintaining part of an optical cable jacket connection part, characterized in that it is connected to a base metal fitting via.