JPH09101420A - Fiber optic cable puller - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: In a conventional pulling tool, an optical fiber equipped with a connector cannot be stored at a high density, and there is not sufficient tension resistance, and the optical fiber is damaged by twisting during pulling. There was something to do. An exterior body (8) and a connector housing (1)
1) and a connecting sleeve (1) for fixing the tension member.
2) and a gripping part (1 for gripping the optical fiber cable
0), the tip of the gripping part is an opening (10a), a supporting member is installed in the opening, the connecting sleeve is fitted to the supporting member, and the through hole (33) of the supporting member is inserted. The tension member is crimped and fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulling tool for an optical fiber cable, and more particularly to a pulling tool for pulling an optical fiber cable having a connector attached to an optical fiber core lead out from a terminal.

[0002]

2. Description of the Related Art When laying an optical fiber cable,
Generally, a method of pulling a pulling tool attached to the end of the optical fiber cable with a winch or the like is used. Generally, as shown in FIG. 5A, when the optical fiber cable 2 is installed in an optical communication network for a telephone line, the optical fiber cable 2 from the telephone station 1 is mainly used in the underground conduit 3. Through the subscriber's house 9 or the subscriber's building 9a. In the case of laying an underground pipe, the optical fiber cable 2 is connected to a traction tool 5 and a traction rope 4 is connected to the tip of the traction tool as shown in FIGS. By driving the towing machine 7a and winding the tow rope 4, the optical fiber cable 2 is unwound from the cable drum 6 installed in the pulling direction (left side in the drawing), and the optical fiber cable is laid. Even when the optical fiber cable is laid between the columns arranged in a plurality of rows on the ground, the pulling device 5 is pulled by the pulling device such as the winch.
It is common to pull and lay the optical fiber cable attached to the.

Conventionally, a pulling tool for an optical fiber cable (hereinafter abbreviated as a pulling tool), as shown in FIG. 3, has a tension member 7 for the optical fiber cable and a hexagon nut 14.
The steel wire 7a connected to the steel wire 7a is inserted through the central part of the pulling tool and connected to the tow hook 9, and the tension member 7 connected to the steel wire 7a is towed to pull the optical fiber cable. Was there. The traction tool 5a as described above includes the tension member 7 and the steel wire 7a at the center of the traction tool.
It is called the central traction type because it is inserted.

The center-pulling type pulling tool 5a protects the optical fiber T having the connector C attached thereto from contact with the steel wire 7a, so that a guide or a holder (not shown) for the connector C is provided in the connector housing 11. ) Had to be placed. Therefore, the number of the connectors C in which the optical fibers T are mounted is limited. Therefore, a pulling tool 5b called an exterior pulling type, which attempts to increase the number of stored connectors C by removing the tension member 7 from the inside of the housing 11 of the connector, is being studied.

As shown in FIG. 4, the exterior pulling type pulling tool 5b defines a connector storing portion 11 for storing the optical fiber having the connector C mounted therein, and a pulling metal fitting to which the pulling rope 4 is connected. An outer package 8 having a base end 9 and having a proximal end screwed to the grip component 10 with a screw 25, and a sheath 15 provided on the outer package 8 and formed at the end of the optical fiber cable 2 are gripped. It comprises a gripping component 10 having a retaining portion 16 and a coupling sleeve 12 which is inserted into a coupling hole 13a provided at the tip of the gripping component 10 and to which the tension member 7 is crimped and fixed.

The connecting sleeve 12 is inserted into the insertion hole 13a provided at the front end of the grip part 10 in the pulling direction with a certain clearance. This insertion hole 1
The peripheral wall portion 13 that engages with the peripheral connecting sleeve of 3a is
The front surface of a flange 12a projecting from the outer periphery of the connecting sleeve 12 comes into contact with the rear surface of the peripheral wall portion 13 so that the flange 12a is formed in a shape capable of engaging with the connecting sleeve 12. Further, the front surface of the peripheral wall portion 13 of the grip component 10 is locked to the connecting sleeve 12 via a washer 18 by a nut 19 which is screwed to a screw portion at the tip of the rigid portion 12b of the connecting sleeve in the pulling direction. . The insertion hole 13a is
The dimension in the axial direction is 10 mm, and the inner diameter is a dimension mainly due to a clearance of about 5 mm between the inner diameter and the connecting sleeve 8.

The tension member 7 led out from the optical fiber cable 2 has its tip at the connecting sleeve 1.
2, the rigid portion 12b of the connecting sleeve 12 is partially deformed by compression and crimped and fixed. The optical fiber cable 2 has a sheath 15 formed at its tip.
The holding portion (demon eyes) 16 of the grip component 10 grips the inside of the grip component 10 to be fixed inside the grip component. The connector C is attached to the tip of the optical fiber T that is output from the optical fiber cable 2. This connector C is used for connection with an optical fiber output from another optical fiber cable after completion of pulling.

The optical fiber T to which the connector C is attached is housed in the connector housing portion 11, and the optical fiber cable 2
When the attachment of the optical fiber cable 2 to the pulling tool 5b is completed, the optical fiber cable 2 is laid by pulling the pulling tool 5b. When the pulling tool 5b is pulled, the pulling force is transmitted from the screw 25 that screws the exterior body to the connecting sleeve 12 through the grip component 10, and is applied to the tension member 7 crimped and fixed to the connecting sleeve 12. .

[0009]

By the way, in order to construct a recent subscriber optical communication network, the conventional tractor has the following problems. That is, the subscriber optical communication network is
It requires a very large number of cords. However, in the conventional center-pull type tractor, the connector is stored using a connector holder in order to avoid contact between the steel wire connected to the tension member inserted through the central axis of the tractor and the optical fiber with the connector attached. Therefore, the storage density could not be increased. Also, in the case of an external pulling type puller, the washer and nut for fixing the connecting sleeve, which are provided at the leading end of the connecting sleeve in the pulling direction, may damage the optical fiber with the connector installed, so there is sufficient storage capacity. There was a problem that could not be obtained.

On the other hand, since construction of a subscriber optical communication network requires long-distance laying, the conventional tractor has a problem that it cannot be efficiently laid because of insufficient tensile strength to withstand long-distance laying. . However, in order to improve the tensile strength with the conventional structure of the tow tool, it is necessary to increase the size of the entire tow tool by increasing the size of the connecting sleeve and the gripping parts. The size of the underground conduit is limited,
There were problems such as loss of versatility.

Furthermore, since there is a limit to the storage capacity of the closure at the connection point, and it is expected that the number of cores of the optical fiber will increase or the installation of a longer distance will be continued in the future, at least the size of the current traction tool will be changed. There is a need for a traction device with high tensile strength that can withstand long-distance installation without any problems. Also,
When the pulling force is applied to the optical fiber cable during installation by the pulling tool, the optical fiber cable is twisted, which causes damage such as breakage of the optical fiber. Preventing damage to the optical fiber due to twisting was also an issue.

The present invention has been made under such a background, without changing the size of the current traction device,
It can store a large amount of optical fibers with connectors installed at high density, and can be laid for a long time with high tensile strength.
An object of the present invention is to provide an optical fiber cable pulling tool configured to prevent damage to the optical fiber due to twisting of the optical fiber cable during pulling.

[0013]

The present invention adopts the following means in order to solve the above problems. That is, the invention according to claim 1 is a tractor (G) which is attached to a tip end portion of an optical fiber cable (2) and connects the tip end portion to a tow rope (4). An exterior body (8) which is provided substantially coaxially around the tip part, accommodates the optical fiber (T) led out from the tip part, and has a tow hook (9) used for connection with the tow rope. A fastening portion (16) supported by the outer casing and fixed to the outer skin at a position closer to the proximal end portion than the distal end portion of the optical fiber cable; Grasping part (1
0) and a connecting sleeve (12) that comes into contact with the other end of the holding component via a supporting member (30), the connecting sleeve being a tension drawn from the tip of the optical fiber cable. It is crimped and fixed to the member (7) and contacts the supporting member via the surface of the optical fiber cable facing the base end side, and the other end of the gripping part is directed to the tip end side of the optical fiber cable. It is characterized in that it comes into contact with the support member through the facing surface.

A second aspect of the present invention is the optical fiber cable pulling device according to the first aspect, wherein the engagement flange of the connecting sleeve separates a distance d between diametrically opposite ends of a disk having a diameter D. The connecting sleeve is formed into a shape notched by two straight lines which are kept apart from each other and are parallel to each other, and is fitted into a fitting recess having a width d, whereby the rotation of the connecting sleeve is prevented and the supporting member is supported. It is characterized by being fitted to.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a pulling tool for an optical fiber cable according to the present invention will be described below with reference to FIGS. In the figure, reference character G is an optical fiber cable pulling tool of the present embodiment (hereinafter, abbreviated as a pulling tool). The difference between the pulling tool G of the present embodiment and that of FIG. 4 is that
The connecting sleeve 12 has a tip opening surface 10a of the grip component 10.
Is to be engaged with the support member 30 provided on the gripping member, and the support member 30 is screwed and locked to the tip of the grip component. In the figure, the same components as those in FIGS. 3 and 4 are designated by the same reference numerals to simplify the description.

FIG. 1 shows the structure of the present pulling tool as shown in FIG.
FIG. 2B shows a cross-sectional structure of the base end portion of the traction tool, and FIG. 2C shows a cross-section of the connecting sleeve. Reference numeral 8 is an exterior body, 1
Reference numeral 1 is a connector housing portion, 10 is a holding component, and 30 is a supporting member. Inside the exterior body 8 to which the tow rope 4 which is the tow means is attached at the tip (on the right side in the figure), from the tip in the tow direction, the connector housing portion 11, the connecting sleeve 12, the supporting member 30 for the connecting sleeve 12, and the gripping part 10 Is provided. In addition, the exterior body 8 includes the tow metal fitting 9 and the screw 25.
The central portion 8 is formed of a metal tube that is made flexible by combining a corrugated tube and a metal mesh, except for the base end portion 8a that is screwed to the grip component 10.

The tension member 7 led out from the tip of the optical fiber cable 2 is fixed to the connecting sleeve 12 by crimping. The tension member 7 is inserted into an insertion hole 33 formed in the center of the support member 30, and is guided into a connection sleeve 12 fitted in a fitting recess 32 formed in a wall portion of the support member 30 in the pulling direction. Then, the rigid portion 12b of the connecting sleeve 12 is compressed and deformed to be crimped and fixed.

On the other hand, in the optical fiber cable 2, the sheath 15 provided at the distal end portion of the optical fiber cable 2 has the holding portion 1 of the holding component 10.
6 is gripped by using the onime 16a. Further, a screw hole is provided on the proximal end side of the grip component 10, and the exterior body 16 is fixed to the grip component by a screw 25.
The leading end of the grip component 10 on the pulling side has an opening 10a.
The support member 30 is installed in the opening 10a, and the tension member 7 of the optical fiber cable is crimped and fixed to the opposite side of the opening of the holding component 10 of the support member 30.

As shown in FIG. 2 (c), the connecting sleeve 1
2 is composed of a cylindrical rigid portion 12b and an engaging flange 12a, and the engaging flange 12a is provided so as to project outward from the base end of the rigid portion 12b in the pulling direction. The engagement flange 12a is fitted in the fitting recess 32 formed in the central portion of the support component 30 on the pulling side (FIG. 2 (b)). As shown in FIG. 2C, the engagement flange 12a has a shape in which two diametrically opposite ends of a disk having a diameter D are cut away by two parallel straight lines that are spaced apart from each other at a distance d.

The grip component 10 is a substantially cylindrical tubular body, and the tip in the pulling direction is an opening 10a.
Then, the support member 30 is screwed into the cylindrical wall surface 10 of the opening 10a so as to bridge the opening 10a.
b. On the other hand, a holding portion 16 for fixing the optical fiber cable is provided at the base end portion of the grasping component, and the sheath 15 formed at the tip end portion of the optical fiber cable is fixed by the demon eye 16a. Further, the grip component 10
Has an engagement concave portion 26 formed on the outer peripheral portion on the base end side thereof, and the engagement concave portion 26 engages with the engagement wall portion 25 formed on the terminal end portion of the exterior body 8.

A through hole 33 through which the tension member 7 is inserted is formed in the center of the support member 30 which is erected and fixed to the front opening 10a of the grip component 10.
Further, a fitting concave portion 32 is formed on the pulling direction side of the support member 30, and the engaging flange 12a of the connecting sleeve 12 is fitted therein. The tip end of the tension member 7 led out from the optical fiber cable 2 is guided through the insertion hole 33 of the support member 30 into the connecting sleeve 12, and the rigid portion 12b of the connecting sleeve 12 is compressed and deformed to be crimped. It is fixed by crimping.

As described above, the engagement flange 12a of the connecting sleeve 12 has a shape in which a disk having a major axis D is cut out in parallel with the width d. The width of the fitting recess 32 of the support member 30 is set to d as shown in FIG. 2 (b). Therefore, the engagement flange 12a having the width d of the connecting sleeve 12 to which the tension member 7 is crimped and fixed is fitted into the fitting concave portion 32 having the width d of the supporting member 30, whereby the connecting sleeve is prevented from rotating. This is the detent means.

The towing tool G of the present invention is assembled in the following procedure. First, the optical cable 2 is inserted into the grip component 10. Next, the tension member 7 led out from the optical fiber cable 2 is introduced into the through hole of the connecting sleeve 12 through the insertion hole of the supporting member 30, and the rigid portion of the connecting sleeve 12 is compressed and deformed to be crimped and fixed. To be done. The engaging flange 12a of the connecting sleeve 12 to which the tension member 7 is fixed is fixed to the supporting member 3
It is fitted into the fitting recess of 0. At this time, since the width of the fitting concave portion 32 of the support member 30 is d, the parallel straight lines separated by the length d of the engagement flange 12a are the screw 3 of the support member 30.
It will be fixed perpendicular to the axis connecting 1s.

After the connecting sleeve 12 is thus fitted to the supporting member, the supporting member 30 is screwed and fixed to the front surface 10b of the opening 10a of the holding component 10 with the screw 31. Next, the sheath 15 formed at the end of the optical fiber cable 2 is fixed by the demon eye 16a of the fastening portion 16.

Then, the optical fiber T output from the optical fiber cable is guided to the connector accommodating portion through the opening 10a of the holding component 10. Then, the connector C is attached to the tip of the optical fiber T. And the exterior body 8
Is covered from the connector storage portion 11 so as to wrap the gripping component 10, and the engaging wall portion 25 of the exterior body 8 and the engaging recess 26 of the gripping component 10 are engaged, and the assembly is completed.

In the pulling tool G, as described above, the optical fiber ejected from the optical fiber cable is the gripping part 1
It is configured to be guided to the connector storage portion 11 through a wide opening portion 10a of 0. That is, the washer or nut that interferes with the insertion of the optical fiber is removed,
Moreover, since there is no tension member or the like in the connector storage portion 11 that causes damage to the optical fiber when the core wire stored in the pulling terminal is congested, it is not necessary to use a connector holder or the like, and the connector storage portion 11 is not necessary. The whole can be freely used to store the connector, which can increase the storage density and greatly increase the storage capacity.

When the optical fiber cable 2 is pulled and laid by using the pulling tool G, the pulling force is first applied to the exterior body 8, and the engagement wall portion 25 of the exterior body engages with the engagement concave portion 26 of the grip component 10. Through the connecting sleeve 12. As a result, the pulling force is applied to the connecting sleeve 12 as a force for pulling the connecting sleeve fixing the tension member 7 in the direction opposite to the pulling. In the pulling tool G, most of the length of the rigid portion 12b of the connecting sleeve 12 is used for crimping and fixing the tension member, and the length is about 1.5 times or more as compared with the length of the conventional crimping and fixing portion. Has been done. Therefore, the tension resistance of the tension member 7 fixing portion of the connecting sleeve 12 that bears the traction force is increased to 1.5 times or more. Then, the traction force causes the connecting sleeve 12 to support the support member 3
Since it acts as a force to press 0, no force is applied to the fixing screw 31 of the support member 30.

When pulling the optical fiber cable 2,
The optical fiber cable 2 receives resistance due to friction with the underground conduit. This resistance is applied to the sheath 15 formed at the tip of the optical fiber cable. On the other hand, the pulling of the optical fiber cable 2 by the pulling tool G pulls the tension member 7, so that the relative position of the sheath 15 and the tension member may change, and so-called layer misalignment may occur.

Actually, an internal member called a slot is interposed between the sheath 15 and the tension member 7, and most of the resistance is borne by the adhesion strength between the sheath 15 and the internal member and the tension member 7. It Therefore, 80
Even when it is pulled by a force of 0 kgf, the force that causes the layer deviation is evaluated as 100 kgf or less. In the present pulling tool, since the sheath 15 is held with a gripping force exceeding 100 kgf by the demon eye 16a provided in the gripping component, there is no risk of layer misalignment.

Further, the coupling sleeve 12 has a flange with a disk having a diameter D cut out to have a width d, and the fitting recess 32 of the support member 30 has a width d. The engagement flange 12a of the connecting sleeve is fitted to the support member 30 while being prevented from rotating. The tension member 7 of the optical fiber cable 2 receives a rotational torque due to the twisting of the optical fiber cable when a pulling force is applied, and the optical fiber is damaged when the connecting sleeve 12 rotates due to the rotational torque. As described above, since the connection sleeve is prevented from rotating, damage to the optical fiber due to twisting is prevented.

[0031]

According to the first aspect of the present invention, in the external pulling type pulling tool for the optical fiber cable, the distal end portion of the grasping component is a wide opening, and the supporting member is installed in the opening and the supporting member is attached to the supporting member. The tension member is crimped and fixed to the fitted connecting sleeve. With this configuration, the optical fiber, which is led out from the optical fiber cable and has the connector attached thereto, can be introduced into the connector storage portion through the wide opening of the holding component without being restricted by the washer, the nut, and the like. Further, since there is no obstacle in the storage section that may damage the optical fiber when the stored cores are congested, without using a protection means such as a connector holder,
An optical fiber with a connector attached can be stored freely. Therefore, the storage density is improved and the storage capacity can be greatly increased.

On the other hand, most of the rigid portion of the connecting sleeve is
Since it is used for crimping and fixing the tension member, the tension resistance of the traction device is improved. Further, the pulling force of the pulling tool is applied to the connecting sleeve and the tension member in the direction opposite to the pulling direction. Since the force in the pulling direction is only the force at the time of handling, the load on the fastening portion of the optical fiber cable that receives the force is reduced and the durability is increased.

In the pulling tool for the optical fiber cable according to the second aspect, the connecting sleeve is fitted and supported by the support member while being prevented from rotating. Therefore, according to this configuration, it is possible to prevent the optical fiber from being damaged due to the twisting of the tension member that occurs when the optical fiber cable is pulled.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a schematic configuration of a pulling tool for an optical fiber cable according to the present invention.

FIG. 2 is a schematic configuration diagram showing a configuration on a proximal end side of a pulling tool of an optical fiber cable of the present invention and a sectional view of a connecting sleeve.

FIG. 3 is a configuration diagram showing a configuration of a conventional center-pull type pulling tool for an optical fiber cable.

FIG. 4 is a configuration diagram showing a configuration of a conventional optical fiber cable exterior pulling type pulling tool.

FIG. 5 is an explanatory diagram for explaining a situation of laying an optical fiber cable.

[Explanation of symbols]

G optical fiber cable pulling tool T optical fiber tape (optical fiber) C connector 2 optical fiber cable 4 pulling means (pulling rope) 7 tension member 8 exterior body 10 gripping part 12 connecting sleeve 15 sheath 16 fastening part 25 screw 30 supporting member

Claims (2)

[Claims] 1. A tractor (G) attached to the tip of an optical fiber cable (2) for connecting the tip to a tow rope (4), wherein the tractor (G) is substantially coaxial around the tip of the optical fiber cable. An exterior body (8) which is provided on the top and accommodates the optical fiber (T) led out from the distal end portion and has a tow hook (9) used for connection with the tow rope, and a base end of the exterior body. The holding part (1) is fixed and has a retaining part (16) for fixing the sheath (15) of the optical fiber cable at the proximal end side, and the other end extending in the distal direction of the terminal.
0) and a connecting sleeve (12) that comes into contact with the other end of the holding component via a support member (30), the connecting sleeve being a tension drawn from the tip of the optical fiber cable. While being crimped and fixed to the member (7), it contacts the supporting member via the surface of the optical fiber cable facing the base end side, and the other end of the gripping component is directed to the tip end side of the optical fiber cable. A pulling tool for an optical fiber cable, which is in contact with the supporting member via a facing surface. 2. The engagement flange (12a) of the connecting sleeve (12) is formed by notching two diametrically opposite ends of a disk having a diameter D by two straight lines parallel to each other with a distance d therebetween. By fitting in the fitting recess (32) of the support member (30) having a width d, the connecting sleeve is prevented from rotating and fitted into the support member. Item 1. An optical fiber cable puller according to item 1.