JPS6222125B2 - - Google Patents

Description

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

When connecting optical cables in a straight line or when making a branch connection, an optical cable jacket connection part is provided to protect the connection part.
The optical cable jacket connection part includes a mechanical strength maintaining part to prevent external forces from being applied to the core connection part due to vibrations applied to the cable by passing vehicles, expansion and contraction of the cable due to heat cycles, etc., and a core part. It is generally comprised of an airtight maintenance part for preventing water from entering the line connection part.

As a mechanical strength maintaining section for such an optical cable jacket connection section, those shown in FIGS. 1 and 2 have conventionally been used. The one shown in Figure 1 is for a straight connection, and the one shown in Figure 2 is for a branch connection. In these figures, 1 is an external metal fitting, 2 is an internal metal fitting, 3 is a gripping metal tightening bolt, and 4 is a cable. Outer cover, 5 is the cable core, 6 is the external fitting for branching,
Reference numeral 7 denotes a connecting rod tightening bolt, which is used to tighten the connecting rod (see FIG. 8) that connects the external fitting 1 at the other end of the cable connection part and the external fitting 1. These conventional mechanical strength maintaining parts are constructed by sandwiching the end of the cable sheath 4 in two parts between the external fitting 1 or external fitting 6 and the internal fitting 2, and tightening the gripping fitting tightening bolt 3. By attaching the external fittings 1 or 6 to the ends of the cables to be connected, and connecting the external fittings 1 or 6 to each other with a connecting rod, it is possible to prevent external force from being directly applied to the core wire connection part. It is designed to prevent this. According to such a conventional mechanical strength retaining unit, the cable jacket 4 is sandwiched and tightened between the internal fitting 2 and the external fitting 1, so that sufficient gripping strength is obtained without applying lateral pressure to the cable core 5. be able to.

By the way, this method requires gripping fittings for straight lines and branches depending on the cable type, internal fittings and external fittings of many size types must be prepared, and the number of branches is limited to one branch on each side. All I could do was connect. In addition, since the internal fitting 2 is annular and not divided, if the cable connection section is changed (straight line → branched, etc.) and the internal fitting 2 is replaced, the cable core wire must be cut. had.

In order to eliminate these drawbacks, the present invention separates the external fitting into a common external fitting that can be commonly used for various cables and a plurality of holding spacers prepared according to the outer diameter of the cable. The present invention is characterized in that a plurality of internal metal fittings are prepared according to the outer diameter of the cable core, and the cable jacket is held between the holding spacer and the internal metal fittings. In addition, in order to enable connection of up to two branches of various cables on one side, three through holes are formed in the three common external metal fittings to which three pairs of gripping spacers can be attached.

Embodiments of the present invention will be described below based on the drawings.

3 to 6 are perspective views showing the structure of the first embodiment of the present invention, in which FIG. 3 shows a mechanical strength retaining part for linear connection, FIG. 4 shows an internal fitting 11, and FIG. 6 shows the gripping spacer 13, and FIG. 6 shows the external metal fitting A8. In these figures, 3 is a gripping fitting tightening bolt, 7 is a connecting rod tightening bolt, 8 is an external fitting A,
11 is an internal metal fitting, and 13 is a holding spacer.

Now, the internal fitting 11 inserted between the two-divided cable jacket and the core consists of two paired parts, and one part has a central part 11-2 that is connected to the cable. It has a semicircular shape corresponding to the core, and a protrusion 11-3 is provided on the outer surface by knurling or the like, and a flat plate part 11-1 is formed at both ends of the protrusion 11-3. A screw hole 11-4 is provided. Several types of internal metal fittings 11 are made according to the outer diameter of the applicable cable, and the central part 1 of these
The radius 1-2 corresponds to the outer diameter of the core of each cable.

Next, as shown in FIG. 5, the gripping spacer 13 has a semicircular shape that pairs with the internal fitting 11 to sandwich the cable jacket.
The inner surface of 3 has measures to be taken when the thickness of the outer covering changes.
A plurality of protrusions 13-1 are provided to cope with loads such as creep and the like over a long period of time.
This gripping spacer 13 is also made in several types depending on the outer diameter of the cable to which it is applied, and its inner diameter can be changed depending on the outer diameter of each cable. On the other hand, its outer diameter is constant, and its outer periphery is tightly fitted into the inner circumferential surface 8-3 of the external fitting A8 shown in FIG. Therefore, the wall thickness of the gripping spacer 13 varies depending on the type, but it is made so that the minimum thickness is 1 to 2 mm even in the case of an applicable cable of the largest diameter. The external metal fitting A8 is processed into a shape that can accommodate the gripping spacer 13, and has a stopper 8-1 to prevent the gripping spacer 13 from shifting in the length direction, and screw holes 8 at both ends. -2 is formed. The inner diameter of the inner circumferential surface 8-3 into which the gripping spacer 13 is fitted is set based on the largest diameter cable among the applicable cables.

In such a configuration, in order to attach the external fittings A8, 8 to the cable jacket, the cable jacket is divided into two equal parts of a predetermined length, torn, and then pushed apart, and then a pair of internal fittings 11, 8 that match the cable are attached. 11 is inserted between the cable jacket and the core, and from the outside of the cable jacket, a pair of external metal fittings A8, 8 fitted with a gripping spacer 13 that matches the cable.
, and tighten and fix the cable jacket with a pair of screws 3, 3 passing through the screw holes 8-2, 11-4, 8-2. In this way, the two connected
Attach external fittings A8 to each end of the optical cable, and attach both external fittings A8 to the ends of the optical cable.
By fixing a connecting rod (not shown) with a connecting rod tightening bolt 7, the connecting rods are connected to each other.

According to this first embodiment, the external fittings A8, 8 can be attached without applying a tightening force to the cable core, and the projections 11-3 are provided on the outer surface of the internal fitting 11 and the inner surface of the gripping spacer 13, respectively. , 13-1 prevents the cable jacket from slipping, and since the holding spacer 13 is firmly held from the outside by the external metal fitting A8, it does not deform. Can be gripped strongly.
Additionally, by simply replacing the internal fittings 11 and gripping spacer 13 with ones that match the core diameter and outer diameter of the cable, cables of various thicknesses can be connected without replacing the external fittings A8 and 8. .

Next, FIG. 7 is a partially cutaway perspective view showing the configuration of a second embodiment of the present invention. In this second embodiment, three external fittings A8, B9, and C10 are stacked, and a hole through which an optical cable can be inserted is formed between the external fittings A8 and B9. The spacers 13, 13 and the pair of internal fittings 11, 11 are sandwiched between them, and two holes are formed between the external fittings B9 and C10 through which the branch cable can be inserted. Two pairs of gripping spacers 13 and two pairs of internal fittings 11 are held in the holes.

According to this second embodiment, branch connections for various combinations of cables can be made using the gripping spacer 13.
This can be accomplished simply by replacing the and internal fittings 11. Furthermore, if external fittings A8 and B9 are used, this part can also be used to connect various cables in a straight line.

FIG. 8 is an assembly diagram of the mechanical strength maintaining section of the second embodiment. As shown in this figure, a mechanical strength maintaining section is completed by connecting external fittings A8, 8 and C10, 10 attached to both ends of a cable (not shown) with connecting rods 15, 15. Also, Figure 9 shows the 8th
FIG. 2 is a perspective view showing the overall configuration of an optical cable jacket connection section using the mechanical strength maintaining section shown in the figure. In FIG. 9, reference numeral 20 is an optical cable, 21 is a branch cable, 22 is a core wire, 23 is an end plate, 24 is a rubber tube, 25 is a halved cylindrical main sleeve, 26
is a folded plastic sheet for storing the connecting portion of the core wire 22 and the extra connecting length. As shown in FIG. 9, the mechanical strength retaining portion, which is attached to the outer sheaths of the optical cable 20 and the branch cable 21 and assembled as shown in FIG. 8, is hermetically housed in the main sleeve 25. By connecting the core wires 22 of these cables 20, 21, an optical cable jacket connection portion is completed which can prevent external force from being applied to the core wire connection portion and also prevent water from entering.

In addition, as shown in Fig. 3, external fittings A8, 8
When connecting the external fittings A8, 8 and 8, 8 in a straight line by connecting rods 15, 15,
When the external fittings A8, B9 form a straight line tangent, the external fittings A8, 8 and B9, 9 may be connected by connecting rods 15, 15.

As explained above, in the present invention, the gripping spacer is replaceably attached to the external metal fitting, and the cable jacket is gripped by the gripping spacer and the internal metal fitting, so that a tightening force is applied to the cable core. In addition, the external metal fittings can be attached without adding stress, and protrusions are provided on the outer surface of the internal metal fittings and the inner surface of the gripping spacer to prevent the cable jacket from slipping. Since it is firmly held, it does not deform, and therefore the cable jacket can be strongly gripped.
In addition, by simply replacing the gripping spacer and internal metal fittings, it can be applied to straight or branched connections of many types of optical cables with different outer diameters without replacing the external metal fittings, resulting in a reduction in the number of parts. It is possible to lower prices and improve construction reliability.
Furthermore, since it can be applied to all optical cable jacket connections, it can greatly contribute to the introduction of optical fiber cables, which are expected to increase dramatically in the future.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the configuration of a conventional mechanical strength retaining section for straight lines, FIG. 2 is a front view showing the configuration of a conventional mechanical strength retaining section for branching, and FIG. 3 is a front view showing the configuration of a conventional mechanical strength retaining section for branching. FIG. 4 is a perspective view showing the structure of the internal fitting 11, FIG. 5 is a perspective view showing the structure of the gripping spacer 13, and FIG. 6 is the external fitting. FIG. 7 is a partially cutaway perspective view showing the structure of the mechanical strength retaining section for both straight and branching purposes according to the second embodiment of the present invention, and FIG. 8 is a perspective view of the mechanical strength retaining section according to the second embodiment of the present invention. FIG. 9 is a perspective view showing the overall structure of the optical cable sheath connection section provided with the mechanical strength maintaining section shown in FIG. 8. 4...Cable jacket, 8...External metal fitting A, 9...
...External fitting B, 10...External fitting C, 11...Internal fitting, 11-1...Flat plate part, 11-2...Semicircular center part, 11-3...Protrusion, 13...For gripping Spacer, 13-1... protrusion, 15... connecting rod,
20... Optical cable, 21... Branch cable, 2
2... Heart line.

Claims (1)

[Scope of Claims] 1. Cutting and pushing apart the outer sheaths at the ends of two optical cables whose core wires are connected to each other, and clamping the end sheaths between an inner metal fitting and an outer metal fitting, respectively. Therefore, in the mechanical strength maintaining part of the optical cable sheath connection part in which the external metal fittings are attached to both sides of the core wire connection part and the external metal fittings are connected to each other by a connecting rod, the inner metal fitting has an inner diameter of It is composed of a pair of metal fittings consisting of a semicircular central part that corresponds to the core diameter of the applicable cable and has a protrusion on the outer surface, and a flat plate part extending radially outward from both ends of this central part, and the external metal fitting is Maintaining the mechanical strength of an optical cable sheath connection part, characterized in that it consists of a pair of metal fittings to which a semicircular gripping spacer whose inner diameter corresponds to the outer diameter of the applied cable and which has a protrusion on the inner surface is attached in a replaceable manner. Department. 2. Two optical cables with core wires connected to each other,
The outer sheaths of each end of the branch cable connected to the core wire connection section are cut and pushed apart, and the outer sheaths are sandwiched and tightened between the inner metal fitting and the outer metal fitting to connect the outer metal fitting to the core. In the mechanical strength maintaining part of the optical cable jacket connection part, which is attached to both sides of the line connection part and whose external metal fittings are connected to each other by a connecting rod, the internal metal fittings have an inner diameter that corresponds to the core diameter of the applicable cable. The external metal fittings are composed of a pair of metal fittings each having a semicircular center portion having a protrusion on the outer surface and a flat plate portion extending radially outward from both ends of the central portion, and the external metal fittings include:
It is composed of three metal fittings A, B, and C of different shapes, and a hole through which the optical cable can be inserted is formed between the metal fittings A and B, and two holes through which the branch cable can be inserted are formed between the metal fittings B and C. holes are formed, and semicircular gripping spacers each having an inner diameter corresponding to the outer diameter of the applied cable and having a protrusion on the inner surface are replaceably attached to each of the holes, and the above-mentioned By selecting the internal fittings and the holding spacer according to the core diameter and outer diameter of the applicable cable, it is possible to make a straight connection and a branch connection with up to two branches on one side compatible with several types of cable outer diameters. The mechanical strength retaining part of the optical cable jacket connection part.