Optical cable excess handling unit and optical cable wiring method

The invention relates to a unit for handling the remainder of optical cables wired in a device for mounting telecommunications equipment such as transmission devices, telephone switching devices and so on and to a method for wiring the optical cables using the unit for handling the remainder thereof.

The conventional units for handling the remainder thereof and cable supporting sections known are disclosed in JP-A-222866/1996, for example.

FIG. 1 is an exploded perspective view of construction of a telecommunication equipment unit-mounting device (hereafter, referred as a unit-mounting device) disclosed in the gazette above. FIG. 2 is an enlarged perspective view of construction of the conventional unit for handling the remainder of optical cables, the unit being arranged in the unit-mounting device shown in FIG. 1 . FIG. 3 is an enlarged perspective view of construction of a wire saddle, which is used in the unit shown in FIG. 2 in order to keep hold of the optical cables.

In FIG. 1, a reference numeral 1 denotes a telecommunications equipment mounted unit mounting telecommunications equipment (not shown) such as transmission devices, telephone switching devices and so on, the equipment using optical cables as a means of conveying intelligence. A reference numeral 2 denotes a unit-mounting frame mounting the telecommunications equipment mounted unit 1 thereon. A reference numeral 3 denotes a box-shaped rack including an inner wall face having a mounting section 3 a on which a plurality of unit-mounting frames 2 are mounted. A reference numeral 4 denotes a unit for handling the remainder of optical cables 5 used for transferring signals to the telecommunications equipment (not shown) mounted in the telecommunications equipment mounted unit 1 in order to install the optical cables 5 onto the unit 1 .

As shown in FIG. 2, the unit 4 includes a rectangular, flat-shaped cable supporting section 4 a for holding the loop-shaped remainder 5 a of the optical cables 5 and a pair of supporting arms 4 b extending from both sides of the cable supporting section 4 a . Each front end of the supporting arms 4 b is fixed on an upper face of one wall of the unit-mounting frames 2 to cantilever the cable supporting section 4 a . Two rows of mounting holes 4 c along the length of the cable supporting section 4 a are formed at the cable supporting section 4 a . A wire saddle 6 shown in FIG. 3 is fixed using a screw at the mounting hole 4 c corresponding to a position where the remainder 5 a of the optical cable 5 should be handled, of the mounting holes 4 c scattered over the cable supporting section 4 a . The wire saddle 6 is shaped like a letter U. The wire saddle 6 includes an approximately rectangular-shaped bottom section 6 a , a pair of wall sections 6 b , a pair of tilting sections 6 c and a mounting hole 6 d . The bottom section 6 a has a flat face corresponding to the upper face of the cable supporting 4 a . The wall sections 6 b are so formed at both sides of the bottom section 6 a as to extend upwardly from the both sides. The tilting sections 6 c is formed by bending sharply upper sections of the wall sections 6 b toward an upper space of the bottom section 6 a . The mounting hole 6 d is formed at a central section of the bottom section 6 a and allows insertion of a screw (not shown) which is used for mounting the wire saddle 6 on the cable supporting section 4 a through the mounting hole 4 c . A gap 6 e , which is defined between the tilting sections 6 c of the wire saddle 6 , has a dimension smaller than an outer diameter of the optical cable 5 .

An operation will be explained hereafter.

Initially, plural unit-mounting frames 2 are mounted in the rack 3 from the front as to be stacked in multi-layers and accordingly the unit 1 is mounted on each of the unit-mounting frames 2 . Next, the optical cables 5 , which are tied in a bundle and supplied from above or beneath along rear and side faces of the rack 3 , is installed onto the cable supporting section 4 a of the unit 4 which is mounted on a rear face of the unit-mounting frames 2 . On performing the installation of the optical cable, the wire saddles 6 are so fixed in the mounting hole 4 c of the cable supporting section 4 a that all of them are arranged on a circle. The remainder 5 a of the loop-shaped optical cable 5 is held on the wire saddles 6 arranged on the circle. In this case, the optical cable 5 is pressed downwardly against ends of the tilting sections 6 c in the gap 6 e while the optical cable 5 is sliding on upper faces of the tilting sections 6 c . At this time, the tilting sections 6 c are further bent downwardly due to elastic deformation of the tilting section 6 c with respect to the wall section 6 b . In this way, the gap 6 e , which is defined between the tilting sections 6 c , is spread briefly and becomes to have a dimension larger than the outer diameter of the optical cable 5 . Therefore, the optical cable 5 is mounted in a space enclosed by the wire saddle 6 . The gap 6 e just after the optical cable 5 is passed through becomes to have a dimension smaller than the outer diameter of the optical cable 5 because the tilting sections 6 c return to original positions, respectively. Therefore, even if the optical cable 5 floats in the air, the optical cable 5 is held in the space enclosed by the wire saddle 6 . Moreover, the optical cables 5 held by the wire saddle 6 are connected to optical connectors (not shown) arranged in the telecommunications equipment of the unit 1 , and then the optical cables 5 are fixed in a state of putting them in order.

FIG. 4 is a perspective view of an alternative cable supporting section, which is used in the unit shown in FIG. 2 . FIG. 5 is a perspective view of a state of holding the remainder of the optical cables using the wire saddle shown in FIG. 3 and the cable supporting section shown in FIG. 4 . As shown in FIG. 4 and FIG. 5, with the alternative, three rows of mounting holes 4 c along the length of the cable supporting section 4 a are formed at the cable supporting section 4 a . The central row of the mounting holes 4 c is shifted by one-half of travel between the mounting holes 4 c in a longitudinal direction of the cable supporting section 4 a with respect to the external rows of the mounting holes 4 c . Therefore, two mounting holes 4 c adjacent to each other in the central row and two mounting holes 4 c in the external rows close to the two mounting holes 4 c of the central row are used for handling the remainder 5 a of one optical cable 5 . Moreover, as shown in FIG. 5, in the central row of the mounting holes 4 c , two mounting holes 4 c adjacent to each other, except for both ends of the central row of the mounting holes 4 c , are used for handling two optical cables 5 .

The conventional unit for handling the remainder of the optical cables is however constructed as described above. Therefore, the optical connector (not shown) connected to the optical cable 5 handled using the unit 4 is close to the telecommunications equipment of the unit 1 , and is apart from the unit 4 . Accordingly, it is difficult to perform insertion and removal of the optical cable into and from the optical connector (not shown).

Moreover, with the conventional unit for handling the remainder of the optical cables, handling the remainder 5 a of the optical cables 5 connected to the optical connector on setting up the rack 3 must perform after handling during in-plant fabrication of the unit. The complicated handling results in a poor-workability.

Further, with the conventional unit for handling the remainder of the optical cables, since numerous wire saddles 6 must be mounted on the unit, it takes much time to mount the wire saddles 6 . Accordingly, there is a poor-workability problem.

The invention was made to solve the foregoing problems. Accordingly, it is an object of the invention to provide a unit for handling the remainder of optical cables improving the workability of connecting an optical cable to an optical connector, which is arranged in the device for mounting telecommunication equipment including transmission devices, the telephone switching devices and so on using the optical cables as a means of conveying intelligence, and improving the workability of handling the remainder of the optical cable.

A unit for handling the remainder of optical cables according to the invention, comprises: a cable supporting section holding the remainder of the optical cables; and a connector for interface, arranged at a central section of the cable supporting section to hold ends of the optical cables. In this way, when the optical cables are wired, the optical cables are connected simply to the optical connector arranged at the central section of the cable supporting section. Therefore, it is possible to facilitate check of positions where the optical cables are connected and that of insertion of the optical cables into the optical connector. It is further possible to improve the efficiency of workability during field installation of telecommunications equipment-mounting devices.

With the above arrangement, the cable supporting section may include: a first area for holding previously the remainder of one optical cable during in-plant fabrication; and a second area for holding the remainder of the other optical cable connecting through the connector for interface to an end of the one optical cable held by the first area during field installation of optical cables. In this way, when the remainder of the one optical cable is held previously on the first area during in-plant fabrication performed in advance of the field installation, it is possible to focus on handling the remainder of the specified optical cable on the field installation. As a result, it is possible to eliminate work-site errors, to improve the efficiency of workability and to reduce time for working. Since optical cables arranged during in-plant fabrication of the unit is not complicated with optical cables arranged during field installation, it is possible to facilitate work such as maintenance and so on.

With the above arrangement, at least one cable holder holding individually the remainder of the optical cables may be arranged at the first and second areas of the cable supporting section respectively, and the cable holder may include a wire saddle holding the remainder of the optical cables in being inserted into and passed through the wire saddle; and a cable guide ensuring the shortest bending radius of the optical cables. In this way, it is possible to ensure that the remainder of the optical cables is handled without increasing transmission loss of the optical cables.

With the above arrangement, the wire saddle may be integrated with the cable guide to constitute the cable holder. In this way, since there is no need to handle individually parts constituting the cable holder, it is possible to reduce time for assembling the cable supporting section including work of inserting the optical cables into the wire saddle and to bring down the cost of work.

With the above arrangement, it may further comprise a cover element jacketing the cable holder, wherein at least one part of the cover element is transparent. In this way, it is possible to check the interior of the cable holder through the transparent portion of the cover. Therefore, it is possible to prevent the transmission loss of the optical cables from increasing as a result of the optical cables, which should be wired, being pinched between the cable holder and the cover.

With the above arrangement, the cable holder may be stacked in multi-layers. In this way, it is possible to improve the efficiency of occupancy of the remainder of the optical cables.

We further provide a method for wiring optical cables by placing a unit for handling the remainder of the optical cables, by placing the unit in telecommunications equipment mounting device using the optical cables as a means of conveying intelligence and keeps hold of the remainder of the optical cables on a horizontal face, comprising the steps of: constituting the unit including a cable supporting section holding the remainder of the optical cables; and a connector for interface, arranged on the cable supporting section to hold ends of the optical cables; constituting the cable supporting section including: a first area for holding previously the remainder of one optical cable during in-plant fabrication of the unit; and a second area for holding the remainder of the other optical cable connecting through the connector for interface to an end of the one optical cable held by the first area during field installation of optical cables; handling the remainder of the optical cables in the first area; and placing the unit handled in the previous step in the telecommunications equipment mounting device. In this way, it is possible to improve the efficiency of workability and the productivity of the telecommunications equipment-mounting device, as compared with the case of handling the remainder of the optical cables in the first area after placing the unit for handling the remainder of the optical cables in the telecommunications equipment-mounting device.

FIG. 1 is an exploded perspective view of construction of the conventional telecommunication equipment unit-mounting device.

FIG. 2 is an enlarged perspective view of construction of the conventional unit for handling the remainder of optical cables, the unit being arranged in the unit-mounting device shown in FIG. 1 .

FIG. 3 is an enlarged perspective view of construction of a wire saddle, which is used in the unit shown in FIG. 2 in order to keep hold of the optical cables.

FIG. 4 is a perspective view of an alternative cable supporting section, which is used in the unit shown in FIG. 2 .

FIG. 5 is a perspective view of a state of holding the remainder of the optical cables using the wire saddle shown in FIG. 3 and the cable supporting section shown in FIG. 4 .

FIG. 6 is a perspective view of a state of arranging a unit for handling the remainder of optical cables as embodiment 1 according to the invention in a telecommunications equipment-mounting device as to be stacked in multi-layers.

FIG. 7 is a perspective view of a state of placing the unit in the telecommunications equipment-mounting device shown in FIG. 6 .

FIG. 8 is an exploded perspective view of construction of a cable holder and a cover used in the unit as embodiment 1 according to the invention.

FIG. 9 is an exploded perspective view of a state of arranging the cable holder used in a unit for handling the remainder of optical cables as embodiment 2 according to the invention as to be stacked in multi-layers.

FIG. 10 is a perspective view of construction of a unit for handling the remainder of optical cables as embodiment 3 according to the invention.

FIG. 11 is a perspective view of construction of a cable holder shown in FIG. 10 .

To explain the invention more in detail, the best modes of carrying out the invention will be described with reference to the accompanying drawings.

FIG. 6 is a perspective view of a state of arranging a unit for handling the remainder of optical cables as embodiment 1 according to the invention in a telecommunications equipment-mounting device as to be stacked in multi-layers. FIG. 7 is a perspective view of a state of placing the unit in the telecommunications equipment-mounting device shown in FIG. 6 . FIG. 8 is an exploded perspective view of construction of a cable holder and a cover used in the unit as embodiment 1 according to the invention. Components of the embodiment 1 common to those of the conventional units shown in FIG. 1 to FIG. 5 are denoted by the same reference numerals and further description will be omitted.

In the drawings, a reference numeral 10 denotes a unit for handling the remainder of optical cables. The unit 10 includes a cable supporting section 11 and an optical connector (connector for interface) 12 arranged at a central section of the cable supporting section 11 . The cable supporting section 11 includes a first area 11 a for holding previously the remainder 5 a of the optical cables 5 during in-plant fabrication of the unit, and a second area 11 b for holding the remainder of the other optical cable connecting through the connector for interface to an end of the one optical cable held by the first area 11 a during field installation of optical cables. Each of the first area 11 a and the second area 11 b is a board having a rectangular shape, and a plurality of optical connectors 12 are arranged at a boundary between both areas. The first area 11 a is located at the back of the rack 3 , and the second area 11 b is located at the front of the rack 3 . Moreover, the first area 11 a is located at a position, which is slightly higher than the second area 11 b.

A plurality (with the embodiment 1, four) of cable holders 13 are arranged at the first area 11 a and the second area 11 b of the cable supporting section 11 . As shown in FIG. 8, the cable holder 13 includes a central cylinder 13 a located at a central section of the cable holder 13 and functioning as a hub, and a cable holding section 13 b extending from the central cylinder 13 a in all directions. Amounting hole 13 c is formed at the bottom of the central cylinder 13 a and allows insertion of a screw (not shown), which is used for fixing the cable holder 13 on the cable supporting section 11 . The cable holding section 13 b includes radial sections 13 d each extending outwardly from the bottom of the central cylinder 13 a in the radial direction, standing-up sections 13 e each extending upwardly from a front end of each radial section 13 d , first tabs 13 f each extending from a front end of each standing-up section 13 e toward an upper section of the central cylinder 13 a , and second tabs 13 g each extending outwardly from the upper section of the central cylinder 13 a in the radial direction as to face the first tabs 13 f . Gaps 13 h are formed between the first tabs 13 f and the second tabs 13 g and have the same dimension as the outer diameter of the optical cable 5 . Each gap 13 h is cut in a direction (slanting direction) of intersecting a circumference or tangent of the remainder 5 a of the loop-shaped optical cables 5 mounted on the central cylinder 13 a . The cable holder 13 is formed in one piece of materials such as ABS resins, for example.

An all-transparent cover 14 is mounted on the upper section of the cable holder 13 . A projection (not shown) is formed at a lower section of the cover 14 and engages with upper and outer sections of the standing-up sections 13 e of the cable holder 13 . Moreover, amounting hole 14 a is arranged at a central section of the cover 14 and holds the cover 14 to the cable holder 13 as to align the mounting hole 14 a in the mounting hole 13 c of the cable holder 13 .

Such a unit 10 is mounted on the mounting section 3 a of the rack 3 using a screw 15 as shown in FIG. 7 .

An operation will be explained hereafter.

Initially, the remainder of the optical cables is held previously on the first area 11 a of the cable supporting section 11 of the unit 10 during in-plant fabrication. The remainder 5 a of the optical cables 5 , which will be connected through the connector 12 to an end of the optical cable (not shown) held on the first area 11 a during field installation, is then held on the second area 11 b during the field installation.

With work for handling the remainder, as shown in FIG. 8, the cable holder 13 is held on the cable supporting section 11 using the screw (not shown). The remainder 5 a of the optical cables 5 is then inserted from the gaps 13 h of the cable holding section 13 b into the radial sections 13 d . The insertion work is performed at each cable holding section 13 b formed at a periphery of the central cylinder 13 a in order to arrange the remainder 5 a of the optical cables 5 at the periphery of the central cylinder 13 a in a loop. Next, the cable holder 13 is covered with the cover 14 . At this time, the projection (not shown) formed at the lower section of the cover 14 is engaged with the upper and outer section of the standing-up section 13 e of the cable holder 13 to mount the cover 14 on the cable holder 13 . Here, it is possible to check visually through the cover 14 that the remainder 5 a of the optical cables 5 is not pinched between the cable holder 13 and the cover 14 .

As described above, according to the embodiment 1, the optical connector 12 is arranged at the central section of the unit 10 . In this way, it is possible to facilitate check of positions where the optical cables are connected and that of insertion of the optical cables into the optical connector 12 .

With the embodiment, the cable supporting section 11 of the unit 10 is divided into the first area 11 a for handling the remainder of optical cables during in-plant fabrication and the second area 11 b for handling the remainder of optical cables during field installation. In this way, there is no need to perform two kinds of work for handling the remainder of optical cables with respect to an overlapped area. Further, it is possible to eliminate work-site errors, to improve the efficiency of workability and to reduce time for working. Since optical cables (not shown) arranged during in-plant fabrication of the unit is not complicated with optical cables 5 arranged during field installation, it is possible to facilitate work such as maintenance and so on.

With the embodiment 1, the cover 14 all is so formed as to be transparent. In this way, it is possible to check visually work-site errors such as a pinch of the optical cables 5 from outside through the cover 14 . Therefore, it is possible to improve reliability with respect to work for handling the remainder of optical cables.

With the embodiment 1, the cover 14 all is so formed as to be transparent. Alternatively, there is no need to form the cover 14 all to be transparent, on condition that the cover 14 has a transparent part allowing a worker to check circumstances that the remainder 5 a of the optical cables 5 handled by the cable holder 13 is pinched between the cable holder 13 and the cover 14 .

FIG. 9 is an exploded perspective view of a state of arranging the cable holder used in a unit for handling the remainder of optical cables as embodiment 2 according to the invention as to be stacked in multi-layers. Components of the embodiment 1 common to those of the embodiment 1 are denoted by the same reference numerals and further description will be omitted.

The embodiment 2 is characterized in that the cable holder 13 is so constructed as to be stacked in two layers. In other words, the central cylinder 13 a of an upper-side cable holder 13 is mounted on the central cylinder 13 a of a lower-side cable holder 13 . Each radial section 13 d of the upper-side cable holder 13 is mounted on each radial section 13 d of the lower-side cable holder 13 . Both mounting holes 13 e are locked with one screw (not shown).

As described above, according to the embodiment 2, the cable holder 13 is so constructed as to be double-stacked. In this way, it is possible to improve the efficiency of occupancy of the remainder 5 a of the optical cables 5 .

Moreover, with the embodiment 2, the cable holder 13 is so constructed as to be stacked in two layers. Alternatively, the invention is not limited to the construction above, and the cable holder may be stacked in multi-layers.

FIG. 10 is a perspective view of construction of a unit for handling the remainder of optical cables as embodiment 3 according to the invention. FIG. 11 is a perspective view of construction of a cable holder shown in FIG. 10 . Components of the embodiment 1 common to those of the embodiment 1 are denoted by the same reference numerals and further description will be omitted.

The embodiment 3 is characterized in that the cable holder 13 includes the wire saddles 6 and a cable guide 15 . The wire saddles 6 are arranged on the circumference of a circle having the shortest bending radius of the remainder 5 a of the optical cables 5 at regular intervals. The cable guide 15 is inserted into the wire saddles 6 and ensures the shortest bending radius of the remainder 5 a of the optical cables 5 .

As described above, according to the embodiment 3, the remainder 5 a of the optical cables 5 is arranged at the periphery of the cable guide 15 in a loop, and the cable guide 15 is inserted into four wire saddles 6 through the gaps 6 e arranged on the circumference of the circle. In this way, it is possible to simplify work for inserting the optical cables 5 into the wire saddles 6 and to improve the efficiency of workability of handling the remainder of optical cables.

As described above, the unit for handling the remainder of optical cables according to the invention is adequate for improving the workability of connecting an optical cable to an optical connector and of handling the remainder of the optical cable. The optical connect is arranged in the device for mounting the telecommunication equipment such as transmission devices, the telephone switching devices and so on, the telecommunications equipment mounting device using the optical cables as a means of conveying intelligence.