Pulling sock for telecommunications cable

Abstract

Pulling sock for telecommunications cable. This description relates to a pulling sock (100) for telecommunications cable (101), comprising a pre-cut stripping tube (113) and a pulling wire (115); a device comprising such a pulling sock and an optical cable (101); an optical branching or termination point comprising such a device and a method for pulling a telecommunications cable by means of a pulling sock. Figure for the abstract: Fig. 1B

Description

Title of the invention: Pulling sock for telecommunications cable. Technical field.

[0001] This description relates generally to telecommunications installations, and more particularly to devices and methods for pulling telecommunications cables such as optical cables comprising at least one optical fiber. Previous technique

[0002] Various cable pulling devices and methods have been proposed. The term "cable pulling" refers to operations intended to allow the laying or installation of a cable by exerting a tensile force on one of its ends, typically to insert the cable into a protective sheath, a tube, a cable tray, etc. Among the existing cable pulling devices and methods, the use of cable pullers has been proposed. Pullers comprising a mesh or netting sheath are known, the mesh being made, for example, from wires of a metallic or plastic material.

[0003] However, existing cable pulling devices and methods, particularly for optical cables, suffer from several drawbacks. Existing cable pulling socks, in particular, are unsatisfactory because they require the use of tools, such as a cutting tool, to remove them after the cable has been pulled. This makes the cable pulling operation longer, more complex, and less safe, as cutting the sock can damage the cable. Furthermore, the use of mesh-sheathed cable pulling socks presents several disadvantages, notably the fact that one or more connectors attached to the cable ends can become stuck in the mesh or even be damaged. In addition, unwanted elements can enter the pulling sock by passing through the mesh. Summary of the invention

[0004] There is a need to overcome all or part of the drawbacks of existing cable pulling devices and methods. In particular, it would be desirable to improve existing cable pulling socks for telecommunications cables, especially for optical cables.

[0005] There is a particular need for an optical cable pull sock whose removal, after pulling the cable, does not require the use of any cutting tool or cutting tool.

[0006] For this purpose, one embodiment provides a pulling sock for telecommunications cable, comprising: - a pre-cut tube for stripping; and - a pulling wire.

[0007] According to one embodiment, the pull wire consists of a set of wires, preferably aramid, from the armor of the telecommunications cable.

[0008] According to one embodiment, the pull wire consists of a set of wires, preferably made of aramid, independent of the telecommunications cable.

[0009] According to one embodiment, the pre-cut tube is a heat-shrinkable sleeve.

[0010] According to one embodiment, the heat shrink sleeve has a shrinkage coefficient in a range from 2:1 to 6:1, preferably in a range from 2:1 to 4:1, more preferably equal to about 2:1 or 3:1.

[0011] According to one embodiment, the pre-cut tube comprises at least one pre-cut line comprising a plurality of holes each passing through the entire thickness of the pre-cut tube.

[0012] According to one embodiment, the pre-cut tube has a cylindrical shape with a circular cross-section.

[0013] According to one embodiment, each pre-cut line extends along a generatrix of the cylinder formed by the pre-cut tube.

[0014] According to one embodiment, the pre-cut tube has a length between approximately 100 mm and approximately 600 mm, for example equal to approximately 500 mm.

[0015] According to one embodiment, the pre-cut tube has a tensile strength on the order of several tens of newtons, preferably between about 80°N and about 250 N.

[0016] One embodiment provides a device comprising: - an optical cable including at least one optical fiber; and - a pulling sock as described, located at one end of the optical cable.

[0017] According to one embodiment, the optical cable comprises several optical fibers, the pull sock enclosing connectors located respectively at the ends of the optical fibers, the cable armor wire assembly extending out of a sheath of the optical cable and said sheath.

[0018] According to one embodiment, the optical cable comprises a single optical fiber, the pull sock enclosing a connector located at the end of the optical fiber and the armor wire assembly located opposite the connector.

[0019] One embodiment provides an optical branching point comprising: - a device as described; - a base; - a reel for winding the optical cable mounted to rotate relative to the base; and - a protective cover.

[0020] One embodiment provides for an optical termination point comprising: - a device as described; - a base; - a reel for winding the optical cable mounted to rotate relative to the base; and - a protective cover.

[0021] One embodiment provides a method for pulling a telecommunications cable using a pulling sock as described, the method comprising the following steps: a) insertion of the pre-cut tube around one end of the cable; b) mechanical fixing of the pre-cut tube to the cable; c) after pulling the cable, remove the pre-cut tube by peeling.

[0022] According to one embodiment, in step c), the removal of the pre-cut tube is carried out manually, without a cutting tool. Brief description of the drawings

[0023] These features and advantages, as well as others, will be described in detail in the following description of particular embodiments, given by way of non-limiting example, in relation to the accompanying figures, among which:

[0024] [Fig.1A] and [Fig.1B] are schematic and partial views illustrating successive steps of a method for implementing a pulling sock for an optical cable according to an embodiment;

[0025] [Fig.2A] and [Fig.2B] are schematic and partial views illustrating successive steps of a method for implementing a pulling sock for an optical cable according to an embodiment;

[0026] [Fig.3A] and [Fig.3B] are schematic and partial views illustrating successive stages of an implementation variant of the draw sock of figures 2A and 2B;

[0027] [Fig.4] is a schematic and partial view of an example of a pre-cut tube of a pulling sock of a telecommunications cable according to an embodiment;

[0028] [Fig. 5] is a schematic and partial perspective view illustrating an example of an optical termination point comprising a pull sock according to one embodiment; and

[0029] [Fig.6] is a schematic and partial perspective view illustrating an example of an optical branching point comprising a pull sock according to one embodiment. Description of the implementation methods

[0030] The same elements have been designated by the same reference numerals in the different figures. In particular, the structural and / or functional elements common to the different embodiments may have the same reference numerals and may have identical structural, dimensional and material properties.

[0031] For the sake of clarity, only the steps and elements useful for understanding the described embodiments have been shown and detailed. In particular, the various applications of optical cables, optical termination points, and optical branch points in this description have not been detailed, as the described embodiments are compatible with all or most common applications using optical cables, optical termination points, and optical branch points, possibly with adaptations within the grasp of a person skilled in the art upon reading this description.

[0032] Unless otherwise specified, when referring to two elements connected together, this means directly connected without intermediate elements other than conductors, and when referring to two elements coupled together, this means that these two elements can be connected or linked through one or more other elements.

[0033] In the following description, when reference is made to absolute position qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative position qualifiers, such as the terms "above", "below", "superior", "inferior", etc., or to orientation qualifiers, such as the terms "horizontal", "vertical", etc., reference is made, unless otherwise specified, to the orientation of the figures.

[0034] Unless otherwise specified, the expressions "approximately", "about", "substantially", and "in the order of" mean to within 10% or 10°, preferably to within 5% or 5°.

[0035] One of the objectives of the described embodiments is to facilitate the pulling of a telecommunications cable, for example an optical cable comprising at least one optical fiber, by an operator. One embodiment is particularly aimed at reducing the number, duration, and difficulty of the operations associated with pulling cables. Another embodiment is further aimed at limiting the risks of damage to the cable and injury to the operator during these operations.

[0036] After using a cable pulling sock that has enabled the pulling, laying or installation of a cable in a protective sheath, a tube, a cable tray The cable, etc., is detached from the cable by an operator, usually using a cutting tool with at least one blade, such as scissors or a utility knife. This operation is delicate because if the operator's technique is inaccurate, the blade can injure them or cut the cable, weakening it or even rendering it unusable.

[0037] According to the embodiments described, a pulling sock is provided, the removal of which after pulling the cable does not require the use of any tool, in particular no cutting tool.

[0038] To avoid any cutting operation using a tool when removing the pulling sleeve, the described embodiments provide for the use of a pre-cut tube, for example, a section or sleeve of pre-cut sheathing. Before the pulling operation, one end of the cable from which the operator wishes to pull the cable is inserted into the pre-cut tube. The cable has, for example, one or more connectors at this end. In the case of an optical cable comprising one or more optical fibers, for example, a fiber optic whip, a connector or plug of type "LC" is, for example, located at the end of each optical fiber.

[0039] The connector(s) are placed inside the pre-cut tube. In one embodiment, the pre-cut tube is a section of heat-shrink tubing. In this case, the pulling sleeve is then heated, for example with a hot air gun, a lighter flame, etc., to cause the heat-shrink tubing to shrink, i.e., to reduce its diameter in the case of a cylindrical tubing with a substantially circular cross-section. The heat-shrink tubing thus conforms to the shape of the end of the cable to be pulled. More precisely, the heat-shrink tubing encloses the cable sheath, the end(s) of the optical fiber(s), and the connector(s).

[0040] The cable is then pulled, for example, by directly using the pulling sock or by using a pulling needle temporarily attached to the pulling sock. The pulling sock is then removed by "peel," for example, by opening the pre-cut tube along at least one pre-cut line. The operation of removing the pre-cut tube after pulling the cable is carried out manually by the operator without using any tools, in particular without using any cutting tools. Removing the pulling sock is thus greatly facilitated, and the risks of damage to the optical cable or injury to the operator are significantly reduced.

[0041] In the case of heat-shrink tubing, the external dimensions and the shrinkage of the heat-shrink tubing sleeve are, for example, chosen so as to allow the end of the cable to be pulled to be easily inserted into the sleeve before shrinking, and so that it can enclose an unstripped portion of the cable and the connector(s) at the end of the optical fiber(s). For this purpose, the heat-shrink sleeve of the pulling sock has, for example, a shrink ratio, that is, a ratio between the diameter of the sleeve before heating and the minimum diameter of the sleeve after heating, within a range of 2:1 to 6:1, for example, within a range of 2:1 to 4:1, for example, approximately 2:1 or 3:1. As an example, in a case where the connectors form an assembly with external dimensions greater, for example, approximately three times greater, than those of the optical cable, a shrink ratio of approximately 3:1 is chosen.

[0042] As an alternative or supplement, the pre-cut tube can be held mechanically attached to the optical cable by one or more mechanical means, for example one or more clamps.

[0043] [Fig.1A] and [Fig.1B] are schematic and partial views illustrating successive steps of a method for implementing a pulling sock 100 of an optical cable 101 according to an embodiment.

[0044] In the illustrated example, the optical cable 101 comprises one or more optical fibers 103 (twelve optical fibers 103 in the example shown), each equipped with a connector 105, for example, an LC-type connector or plug. The optical cable 101 is said to be "pre-connectorized." By way of example, the optical cable 101 is first stripped by removing a portion of a sheath 107 surrounding the optical fibers 103, for example, over a length of approximately 400 mm, and then the connectors 105 are attached to the ends of the optical fibers 103.

[0045] In the example shown, the optical fibers 103 of the optical cable 101 are of different lengths. This advantageously allows for staggered positions of the connectors 105. In the illustrated example where the optical cable 101 has twelve optical fibers 103, the connectors 105 are grouped into four sets of three connectors 105. The optical cable 101 has, for example, a maximum overall size, or outer casing, of between 20 and 25 mm. This corresponds, for example, approximately to the diameter of a circle in which three connectors 105 of the optical cable 101 are inscribed.

[0046] As an alternative, the optical fibers 103 may have the same length, within manufacturing variations. This corresponds, for example, to a case in which the optical cable 101 has a number of optical fibers 103, and therefore a number of connectors 105, less than or equal to four, preferably less than or equal to three.

[0047] In the example shown, a heat-shrink sleeve 109 encloses the optical fibers 103 and the sheath 107 near the end of the sheath 107 from which the optical fibers 103 emerge. The sleeve 109 allows, for example to avoid damaging the end of the sheath 107 during handling of the optical cable 101. As an alternative, the sleeve 109 may be omitted.

[0048] In the example shown, the optical cable 101 comprises a set of wires 111 made of a tensile-resistant material, for example, aramid armor wires, giving the cable 101 good tensile strength. The aramid wires 111 are, for example, exposed by stripping the end of the sheath 107 of the optical cable 101.

[0049] According to one embodiment, the pull sock 100 comprises a pre-cut tube 113 and a pull wire 115. In the example shown, the pull wire 115 is made up of the armor wires 111, for example aramid, of the optical cable 101. The wires 111 are for example knotted so as to form a loop 117 which, after the pre-cut tube 113 of the pull sock 100 is put in place, exerts a tensile force on the optical cable 101 which makes it possible to pull the pre-connectorized cable 101, for example to pass it through a protective sheath.

[0050] The unstripped part of the optical cable 101 has, for example, a substantially circular cross-section with a diameter of approximately 3 mm.

[0051] In the example shown, the pre-cut tube 113 of the pull sock 100 is formed by a section of pre-cut heat-shrink tubing conforming to the shape of the group of connectors 105 located at the ends of the individual optical fibers 103. This facilitates pulling the optical cable 101, for example into a conduit, by preventing the connectors 105 from getting stuck or being damaged during pulling. The section of heat-shrink tubing 113 has a dotted pre-cut line 119 extending along a longitudinal direction of the section 113. Although only one pre-cut line 119 is visible in [Fig. 1B], the section of heat-shrink tubing 113 can include any number of pre-cut lines 119 to facilitate its removal after pulling the optical cable 101.

[0052] As an alternative or additional feature, one or more mechanical retaining elements for the pre-cut tube 113 around the sheath 107, the optical fibers 103, and the connectors 105 of the optical cable 101 may be provided. This corresponds, for example, to a variant in which the pre-cut tube is not heat-shrinkable. By way of example, each mechanical retaining element is a cable tie, for example, made of polyamide or plastic, for example, known by the trade name "Rilsan".

[0053] Depending on the application, the optical cable 101 can be pulled by exerting a pulling force directly on the loop 117 or by using a pulling needle mechanically fixed to the loop 117. The pulling needle allows, for example, the optical cable 101 to be installed in longer conduits than when using the pulling sock 100 alone.

[0054] Fig. 2A and Fig. 2B are schematic and partial views illustrating successive steps of a method for implementing a pulling sock 200 of an optical cable 201 according to an embodiment.

[0055] The optical cable 201 of Figures 2A and 2B differs from the optical cable 101 of Figures IA and IB in that the optical cable 201 is "single-fiber," that is, it comprises a single optical fiber 103 (not visible in Figures 2A and 2B) one end of which is equipped with a connector 205, for example, an LC connector or plug. In this example, the aramid armor of the optical cable 201 does not extend beyond the sheath 107.

[0056] The pull sock 200 is, for example, analogous to the pull sock 100. In the example shown, the pull sock 200 comprises the pre-cut tube 113 and differs from the pull sock 100 in that the pull wire 115 of the pull sock 200 comprises a set of wires 211, for example, made of aramid, independent of the optical cable 201. In the example shown, one end 216 of the wires 211 is knotted and intended to be placed opposite the connector 205, and another end 217 forms a loop intended to be placed outside the pre-cut tube 113 of the pull sock 200 to allow the optical cable 201 to be pulled. The knot formed on the connector 205 side is intended to be clamped by the pre-cut tube 113, for example after shrinking by exposure to a heat source, for example from a hot air gun, a flame for example from a lighter, etc., in the case where the pre-cut tube 113 is a section of heat-shrink tubing. .

[0057] Fig. 3A and Fig. 3B are schematic and partial views illustrating successive stages of an implementation variant of the 200 draw sock of Figures 2A and 2B.

[0058] The variant of Figures 3A and 3B differs from the embodiment of Figures 2A and 2B in that, in the variant of Figures 3A and 3B, the end 216 of the wire assembly 211 is knotted around the connector 205 of the optical cable 201. By way of example, the knot used is a clove hitch, a bowline, etc., or, more generally, any type of knot suitable for exerting traction on the connector 205.

[0059] The [Fig.4] is a schematic and partial view of the pre-cut tube 113 of the draw sock 100 or 200 according to one embodiment.

[0060] In the illustrated example, the pre-cut tube 113 has a cylindrical shape with a substantially circular cross-section. The pre-cut tube 113 has, for example, three longitudinal cut lines 119 that are substantially parallel to each other. Each pre-cut line 119 comprises a plurality of holes, each passing through the entire thickness of the pre-cut tube 113, separated from each other by uncut portions of the pre-cut tube 113. The pre-cut lines 119 are adapted to withstand the forces exerted on the pre-cut tube 113 when tightened around the optical cable 101 or 201. For example, during heat shrinking when the tube 113 is a section of heat-shrink tubing, and during cable pulling. The pre-cut lines 119 are also adapted to allow for manual tearing, without the use of a cutting tool, of portions of the pre-cut tube 113 located between the pre-cut lines 119. Each pre-cut line 119 extends, for example, substantially along a generatrix of the cylinder formed by the pre-cut tube 113. The pre-cut tube 113 comprises, for example, at least one and at most four pre-cut lines 119. This example is not, however, limiting; the pre-cut tube 113 may more generally comprise at least one pre-cut line 119.

[0061] The pre-cut tube 113 has, for example, a length between approximately 100 mm and approximately 600 mm, for example, approximately 500 mm. The pre-cut tube 113 also has, for example, a tensile strength on the order of one or more tens, or even hundreds, of newtons, for example, between approximately 80 N and approximately 250 N.

[0062] Fig. 5 is a schematic and partial perspective view illustrating an example of an optical termination point (OTP) 500 comprising the pull sock 200 according to one embodiment.

[0063] In the example shown, the optical termination point 500 comprises: - a base 501; - a 503 reel mounted to rotate relative to the 501 base and on which an optical cable is wound, for example optical cable 201; - a button 505 for locking the angular position of the coil 503 relative to the base 501; and - a 507 cover, or hood.

[0064] In the example shown, the pre-cut tube 113 and the pull wire 115 of the pull sock 200 are positioned inside the optical termination point 500 before the optical cable 201 is installed and connected. The loop 217 formed at the end of the pull wire 115 is, for example, attached inside the optical termination point 500. The pre-cut tube 113 and the pull wire 115 are, for example, protected by the cover 507 once it is closed. This makes it possible, for example, to prevent damage to the pull sock 200 before the optical termination point 500 is installed on site.

[0065] Fig. 6 is a schematic and partial perspective view illustrating an example of an optical branch point (OBP) 600, for example an intermediate or internal branch point, including the pull sock 100 according to one embodiment.

[0066] In the example shown, the optical branch point 600 comprises: - a base 601; - a reel 603 mounted to rotate relative to the base 601 and on which an optical cable is wound, for example optical cable 101; - a 605 receiving plate for at least one pre-connectorized assembly 607; - a button 609 for locking the angular position of the coil 603 relative to the base 601; and - a 611 cover, or hood.

[0067] In the example shown, the pre-cut tube 113 and the pull wire 115 of the pull sock 100 are positioned inside the optical branch point 600 before the optical cable 101 is installed and connected. The loop 117 formed at the end of the pull wire 115 is, for example, attached inside the optical branch point 600. The pre-cut tube 113 and the pull wire 115 are, for example, protected by the cover 607 once it is closed. This makes it possible, for example, to prevent damage to the pull sock 100 before the optical branch point 600 is installed on site.

[0068] Various embodiments and variations have been described. Those skilled in the art will understand that certain features of these various embodiments and variations could be combined, and other variations will become apparent to those skilled in the art. In particular, the embodiment shown in Figures 2A and 2B, in which the pull wire is a set of added armor wires, can be adapted by those skilled in the art, upon reading this description, to the case of optical cable 101. This amounts to using the set of added wires 211 knotted at its two ends 216 and 217, instead of the set of wires 111 from the armor of optical cable 101.

[0069] Moreover, what is set forth more particularly in relation to an example of application to optical cables 101 and 201 applies more generally to any type of telecommunications cable.

[0070] Finally, the practical implementation of the described embodiments and variants is within the reach of a person skilled in the art, based on the functional specifications given above. In particular, the embodiments are not limited to the examples of materials and dimensions described. Furthermore, the length and flexibility of the pre-cut tube 113 are adapted to the routing of the optical cable 101 or 201.

Claims

Demands

1. Pulling sock (100; 200) for telecommunications cable (101; 201), comprising: - a pre-cut tube (113) for peeling; and - a pulling wire (115).

2. Sock (100) according to claim 1, wherein the pull wire (115) is made up of a set of wires (111), preferably aramid, of the armor of the telecommunications cable (101).

3. Sock (200) according to claim 1, wherein the pull wire (115) is made up of a set of wires (211), preferably aramid, independent of the telecommunications cable (201).

4. Sock (100; 200) according to any one of claims 1 to 3, wherein the pre-cut tube (113) is a heat-shrinkable sleeve.

5. Sock (100; 200) according to claim 4, wherein the heat shrink sleeve (113) has a shrink ratio in a range from 2:1 to 6:1, preferably in a range from 2:1 to 4:1, more preferably equal to about 2:1 or 3:

1.

6. Sock (100; 200) according to any one of claims 1 to 5, wherein the pre-cut tube (113) comprises at least one pre-cut line (119) comprising a plurality of holes each passing through the entire thickness of the pre-cut tube (113).

7. Sock (100; 200) according to any one of claims 1 to 6, wherein the pre-cut tube (113) has a cylindrical shape with a circular cross-section.

8. Sock (100; 200) according to claim 7, in its dependence on claim 6, wherein each pre-cut line (119) extends along a generatrix of the cylinder formed by the pre-cut tube (113).

9. Sock (100; 200) according to any one of claims 1 to 8, wherein the pre-cut tube (113) has a length between about 100 mm and about 600 mm, for example about 500 mm.

10. Sock (100; 200) according to any one of claims 1 to 9, wherein the pre-cut tube (113) has a resistance to the traction on the order of several tens of newtons, preferably between about 80°N and about 250 N.

11. Device comprising: - an optical cable (101; 201) comprising at least one optical fiber (103); and - a pull sock (100; 200) according to any one of claims 1 to 10, the pull sock (100; 200) being located at one end of the optical cable (101; 201).

12. Device according to claim 11 comprising a pull sock (100) according to claim 2, wherein the optical cable (101) comprises several optical fibers (103), the pull sock (100) enclosing connectors (105) located respectively at the ends of the optical fibers (103), the armor wire assembly (111) of the cable (101) extending out of a sheath (107) of the optical cable (101) and said sheath (107).

13. Device according to claim 11 comprising a pull sock (200) according to claim 3, wherein the optical cable (201) comprises a single optical fiber (103), the pull sock (200) enclosing a connector (205) located at the end of the optical fiber (103) and the armor wire assembly (211) located opposite the connector (205).

14. Optical branch point (600) comprising: - a device according to claim 12; - a base (601); - a reel (603) for winding the optical cable (101) mounted to rotate relative to the base (601); and - a protective cover (611).

15. Optical termination point (500) comprising: - a device according to claim 13; - a base (501); - a reel (503) for winding the optical cable (201) mounted to rotate relative to the base (501); and - a protective cover (507).

16. A method for pulling a telecommunications cable (101; 201) using a pulling sock (100; 200) according to any one of claims 1 to 10, the method comprising the following steps: a) insertion of the pre-cut tube (113) around one end of the cable (101; 201); b) mechanical fixing of the pre-cut tube (113) to the cable (101; 201); c) after pulling the cable (101; 201), removal of the pre-cut tube (113) by peeling.

17. Method according to claim 16, wherein, in step c), the removal of the pre-cut tube (113) is carried out manually, without a cutting tool.

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