JPS58117513A - Storing method of connection excessive length part of optical fiber - Google Patents

Abstract

PURPOSE:To reduce a box in designed size and to prevent an optical fiber from being twisted by connecting the optical fiber to an optical fiber cord and winding a connection excessive length part both outside the box. CONSTITUTION:The optical fiber 3' of an optical cable 3 is led out of a connection excessive length part storage box 12 through an opening part and then connected to one terminal of the optical fiber cord 9 which is connected previously to a connector 6 at the other terminal outside the box. Then, the optical fiber 3' and optical fiber cord 9 are wound nearly in a circle in this order on a connection excessive length part holding base 11 and fixed with a proper fixture. The holding base 11 is stored in the box 12 while rotated so that the optical fiber between the holding base and optical fiber fixation part is wound on the holding base.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method for accommodating an excess connecting length between an optical fiber and a single-core cord of an optical cable.

A conventional connection extra length storage box will be explained with reference to FIG. In FIG. 1, reference numeral 1 denotes a connection excess length storage box, 2 a storage rack, 8 an optical cable, 4 an optical-electrical converter, and 5 a connector for connecting an optical fiber and an optical fiber cord.

FIG. 2 is an enlarged view of the extra connection length storage box, and the same numbers as in FIG. 1 indicate the same parts. Note that 7 is a fixture for fixing an optical fiber or an optical fiber cord, and 8 is a bracket for fixing the connection extra length storage box l into the storage rack 2. Further, 3' indicates an optical fiber, and 9 indicates an optical fiber cord.

When connecting the optical fiber 8' of the conventional optical cable 3 and the optical fiber cord 9, the optical fiber cord 9 to which the connector 6 is connected in a factory is first prepared.

Since the connection between the connector 6 and the optical fiber cord requires extremely high precision such as axis alignment, it is generally not done at the cable site, but is done at the factory using a special tool with a microscope. As for the optical cable, the coating at the tip is removed to allow the optical fiber to protrude, and after the optical fiber is drawn into the box 1 from the cable entry port, it is properly fixed. Next, the excess connecting length of the optical fiber and the optical fiber cord is fixed to a fixture in the box 1 and wound into a coil to form a substantially circular shape. The extra connection length required for +Ir connection for connection switching etc. is usually 80 to 100 c1n. After winding up the excess length, the optical fiber and the optical fiber cord are connected, but the box requires a large amount of space because it is necessary to insert the tools for connection and the workpiece from outside.

A single optical cable usually has multiple optical fibers, and each is connected to a core optical fiber cord, or connected to a multi-core optical fiber cord, and is fixed by winding up the excess length of the cable. There is a problem that optical fibers or optical fiber cords are easily twisted. If this twisting occurs, it will cause the optical fiber to break, so it must be prevented from twisting, but in order to avoid this, the box L must be made large enough to prevent the optical fiber and optical fiber cord from getting caught in it. The problem is that it doesn't.

The present invention was made to solve the above problems. The present invention will be explained based on FIGS. 3, 4, and 5. In Fig. 8, Fig. 4, and Fig. 5, 3 is an optical cable;
3. is an optical fiber, 4 is an opto-electric converter, 5 is a connection part, 6 is a connector, 7 is a fixture for the optical fiber and optical fiber cord, 7゛ is a fixture for the connection part, 9 is an optical fiber cord, 10 11 is an optical cable fixing device, 11 is a connection extra length holding stand,
12 is a box, and 13.13' is a holding fixture.

The method of accommodating the extra connection portion of the present invention will be explained according to the accommodating procedure. First, the outer sheath at the tip of the optical cable 3 is stripped off to expose the optical fiber, and the cable is pulled in through the cable entry port (not shown) of the box 12 and fixed at an appropriate location. It may be fixed inside the box or outside the box.

Next, the optical fiber 3' is pulled out from the box opening, and the other end of the optical fiber cord 9 to which the connector 6 has been previously connected outside the box is connected to the optical fiber 3'. After that, the optical fiber 3' and the optical fiber cord 9
are rolled up into a substantially circular shape on the connection extra length holding base in that order and fixed with a fixing tool 7 as appropriate. In this case, at least the connecting portion 5 is fixed so that it does not move. The figure shows that the connection part itself is fixed, but since it is sufficient to prevent the connection part from moving, there are cases where the connection part itself is not held with a fixture, but the area around it is fixed.

Next, turn the connection extra length part holder in the direction of the arrow so that the optical fiber between the holder and the optical cable fixing part is wound onto the holder, and insert the holder and the extra length part held on it into the box. to accommodate. The connection extra length holding stand may be a simple disk-shaped plate as shown in the figure, but it can also be made double so that it can easily rotate in the direction of the arrow, so that the lower side supports the rotation of the upper side. Further, after the holding stand is housed in the box, it is fixed with fixtures 13 and 13' so that it does not move.

This fixing tool only needs to be used at one location as it is sufficient to securely fix the holding base. Next, the connector attached to the optical fiber cord is connected to a connector provided on a device such as an optical-to-electrical converter. This optical fiber cord may be led out from the box through holes provided as appropriate, or as shown in box 1, . Other devices may also be accommodated in the device 2 at the same time and connected to the connector there.

In the figure, only one optical fiber cord is shown, but if there are multiple optical fibers, there may be multiple optical fiber cords.

As described above, the present invention has the advantage that the box design can be made smaller because the connection between the optical fiber and the optical fiber cord is performed outside the box. Further, since the excess length of the optical fiber and optical fiber cord is wound in one direction and outside the box, there is an advantage that the optical fiber will not be twisted and accidents of breaking the optical fiber can be prevented.

[Brief explanation of the drawing]

FIGS. 1 and 2 are explanatory diagrams of a conventional method for accommodating an excess connection length, and FIGS. 3, 4, and 5 are explanatory diagrams of a method for accommodating an excess connection length according to the present invention. In the figure, 3 is an optical cable, 3' is an optical fiber, 5 is a connection part, 6 is a connector, 7.7' is a fixing device, 9 is an optical fiber cord, 10 is a cable fixing device, and 11 is a connection extra length holder 12 indicates a box. Direction 3 A 5

Claims (1)

[Claims] (1) In the method for storing the extra length of an optical cable in a box when the optical fiber and the optical fiber cord are connected, the optical cable is drawn into a cable entry port provided in the box and fixed at an appropriate location. Pull out the optical fiber protruding from the tip of the optical cable through the opening of the box, connect the other end of the optical fiber cord with a connector attached to one end in advance, and connect the optical fiber and the remaining optical fiber cord. Wrap the long part of the optical fiber cord in the order of the optical fiber cord onto the connecting extra length holding stand so that it becomes almost circular (fix the connecting part so that it does not move, and then hold the connecting extra length holding stand). The optical fiber between the stand and the above optical cable fixing part is wound onto the connection extra length holder and housed in the box while being rotated in the winding direction, and the above connection extra length holder is not moved within the box. 1. A method for accommodating an excess length of an optical fiber connection, which comprises fixing the fiber cord in the same manner as shown in FIG.