JP5656673B2 - cable - Google Patents

Description

  The present invention relates to a cable that can suppress biting by a rodent.

  Animals belonging to rodents such as moths and momonga (hereinafter referred to as rodents) have the habit of wearing the growing incisors by scoring hard objects. Therefore, when cables such as communication cables and power cables are laid in the rodent's habitat (for example, outdoors underground, in pipes or indoor ceilings), biting by rodents is a problem. Become. Accordingly, various measures for biting have been proposed in order to prevent the cable from being damaged by biting and causing accidents such as electric leakage and fire.

For example, in Patent Document 1, a thermoplastic resin material having a tensile strength of 35 MPa or more is used on the outer periphery of a cable core so that the center line average roughness (Ra value) of the surface is 0.4 μm or less. To form. In Patent Documents 2 and 3, a cable sheath is made to contain an antifungal agent such as capsaicin. That is, in Patent Documents 1 to 3, biting is prevented by configuring the cable itself so that rodent animals do not like it.
In Patent Document 2, a dummy cable having a tensile strength / centerline average roughness smaller than that of the main cable is arranged adjacent to the main cable having a jacket formed on the outer periphery of the cable core. I have to. That is, in Patent Document 5, a rodent animal is caused to bend a dummy cable to prevent the cable from being bitten.
Further, in Patent Document 5, biting is prevented by laying a cable in a protective tube having a tube wall containing an antifungal agent such as capsaicin.

JP 2010-157470 A Japanese Patent Laid-Open No. 10-2223058 Japanese Patent No. 4202206 JP 2010-160918 A JP 2002-271934 A

  However, in the techniques of Patent Documents 1 to 3, since the outer jacket of the cable is reformed, there is a possibility that workability (handling) and safety when laying the cable are lowered. Further, in the technique described in Patent Document 2, since the dummy cable is disposed along the cable, the overall outer diameter (lateral width) is increased, and the cost is increased. In addition, the technique described in Patent Document 3 cannot prevent biting when a rodent animal invades from the end of a protective tube or the like.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a cable that can implement measures against biting with a simple and inexpensive configuration and can improve workability and the like when laying the cable.

The invention according to claim 1 is a cable main body having a jacket formed on the outer periphery of the cable core;
An occlusion-inducing portion having a tensile strength smaller than that of the outer sheath, and an occlusion-preventing portion that is interposed between the attraction-inducing portion and the cable body, and has a tensile strength larger than the tensile strength of the outer sheath. And an external body for biting that is intermittently mounted in the longitudinal direction on the outer periphery of the cable body ,
The cable is characterized in that the biting prevention part is formed so as to protrude from an end face of the biting inducement part .

  According to a second aspect of the present invention, in the cable according to the first aspect, the tensile strength of the biting inducement is 50% or less of the tensile strength of the jacket.

  According to a third aspect of the present invention, in the cable according to the first or second aspect, a tensile strength of the bite attracting portion is 1 MPa or more and 30 MPa or less.

According to a fourth aspect of the present invention, in the cable according to any one of the first to third aspects, the biting prevention part has a tensile strength of 50 MPa or more.

The invention according to claim 5, in the cable according to any one of claims 1 to 4, wherein咬害prevention part, metallic materials, non-metallic fiber-based materials, or any one of a resin-based material It is composed of two.

The invention according to claim 6 is the cable according to any one of claims 1 to 5 , wherein the biting exterior body can change a mounting position with respect to the cable body. Features.

The present inventors conducted various experiments to elucidate the behavior of rodents. Specifically, a sample was prepared by coating a brass bar having the same outer diameter with two different resin materials with the same thickness, placing them in the same cage, and conducting a forced biting test by rats. As resin materials, low-density polyethylene (LDPE), high-density polyethylene (HDPE), urethane-based elastomers, nylon-based elastomers, and other resin materials with different tensile strengths are used in combination. And experimented.
As a result, samples coated with a soft material (for example, LDPE coated samples in the combination of LDPE and nylon elastomer) are severely bitten to the extent that the brass bar is exposed, whereas samples coated with a hard material are There was almost no bite. In particular, a clear difference was confirmed when the ratio of the tensile strength of the resin material was 25% or less.

  As a result, it was found that rodents have the habit of thoroughly scolding only objects that are easy to beat. Furthermore, in the long cable track, it was found that there is a region where biting is likely to occur, rather than biting occurring uniformly in the longitudinal direction. And the inventors obtained knowledge that the biting can be effectively suppressed even by intermittently mounting the outer body for biting more easily than the jacket of the cable main body, The present invention has been conceived.

  According to the present invention, countermeasures against biting can be realized with a simple and inexpensive configuration, and workability at the time of cable laying can be improved.

It is a side view which shows the cable which concerns on embodiment. It is sectional drawing of a cable main body.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a side view showing a cable according to the embodiment, and FIG. 2 is a cross-sectional view of the cable body. In FIG. 1, the mounting part of the external body for biting is shown in a partial cross section. In the present embodiment, a case where the cable body is constituted by a slot type optical fiber cable will be described.

  As shown in FIGS. 1 and 2, the cable 1 according to the embodiment includes a cable body 10 having a jacket 12 formed on the outer periphery of a cable core 11, and an external body 20 for biting attached to the outer periphery of the cable body 10. It is configured with. The external body 20 for biting is intermittently attached to the cable body 10 at a predetermined interval in the longitudinal direction.

  The cable core 11 of the cable body 10 has a configuration in which a presser winding tape 113 is wound around the outer periphery of a slot rod 111 that accommodates the optical fiber tape core wire 112. The slot rod 111 is a linear member made of, for example, a resin such as hard polyethylene, and a tension member (for example, a steel strand) 114 that bears a tension is provided in the axial direction at the center. On the outer peripheral surface of the slot rod 111, a plurality of slots 111a are formed in a spiral in one direction along the axial direction, and a plurality of optical fiber ribbons 112 are accommodated in a stacked state in each slot 111a. Has been. As the optical fiber ribbon 112, for example, a configuration in which eight optical fiber cores having a coating outer diameter of 250 μm are arranged in parallel and are collectively covered with a coating material such as a UV curable resin is used.

The jacket 12 is formed on the outer periphery of the cable core 11 by extrusion molding of a synthetic resin material. As a raw material of the jacket 12, for example, linear low-density polyethylene (LLDPE), HDPE, polyamide resin, or polyurethane elastomer is suitable.
The tensile strength of the jacket 12 is 1 to 30 MPa. According to experiments by the inventors, it has been found that if the outer shell 12 has a tensile strength of 35 MPa or more, the bite by rodents can be suppressed. That is, the jacket 12 of the cable body 10 is configured to be relatively susceptible to biting by rodents.

  Here, the tensile strength of the jacket 12 is a value measured by a tensile test method defined in JIS K 7161 using a test piece obtained by machining a molded product (here, the jacket 12) by punching. The same applies to the tensile strength of the bite attracting part 21 and the tensile strength of the bite prevention part 22 which will be described later.

  The external body 20 for biting has a configuration that induces the bite of rodents, that is, a configuration that rodents prefer to use over the cable body 10. Specifically, the external body for biting 20 includes a biting prevention unit 22 provided on the outer periphery of the cable body 10 and a biting inducement unit 21 provided on the outer periphery of the biting prevention unit 22. The bite attracting portion 21 is a portion that is preferred when the cable 1 is selected as a target for rodents to beat. The biting prevention unit 22 prevents biting from reaching the cable body 10 when a rodent animal hits the biting attraction unit 21.

The biting attraction part 21 is made of a soft resin material having a tensile strength smaller than that of the outer cover 12 and is formed in a cylindrical shape on the outer periphery of the biting prevention part 22. The tensile strength of the biting inducement 21 is preferably 50% or less of the tensile strength of the jacket 12. If the ratio of the tensile strength between the biting inducement 21 and the jacket 12 (the tensile strength of the bite inducement 21 / the tensile strength of the jacket 12) is too large, there is a difference in ease of hitting rodents. This is because a rodent animal may accidentally beat the cable body 10 without being recognized.
That is, by making the tensile strength of the bite attracting part 21 to be 50% or less of the tensile strength of the coat 12, there is a difference in ease of biting between the coat 12 and the bite attracting part 21 for rodents. Since it becomes clear, the bite inducement part 21 can be preferentially beaten.

Moreover, if the tensile strength of the bite attracting part 21 is too small, it will be damaged early and lose its function as a bite countermeasure. It becomes. Therefore, it is desirable that the tensile strength of the biting inducement 21 is 1 MPa or more and 30 MPa or less.
As a raw material of the bite attracting part 21, for example, a rubber material such as silicone rubber or nitrile rubber, a soft elastomer material such as an olefin elastomer, a vinyl chloride elastomer, a styrene elastomer, or a soft plastic material such as a soft PVC is suitable. is there.

  The biting attraction part 21 has, for example, a configuration in which two halves formed by injection molding of a resin material are fitted and fixed to the outer periphery of the biting prevention part 22. Further, for example, the biting inducement part 21 has a configuration in which a self-bonding tape (for example, EFCO tape) made of a resin material is attached to the outer periphery of the bite prevention part 22 in a spiral, horizontal or vertical manner. Or you may make it form the biting inducement part 21 by discharging and solidifying a liquid or gaseous resin material to the outer periphery of the biting prevention part 22 like foaming urethane spray.

The biting prevention unit 22 is made of a hard material larger than the outer cover 12 and is formed in a cylindrical shape on the outer periphery of the cable body 10 (outer cover 12). In addition, the shape of the biting prevention part 22 is not limited to a cylindrical thing, According to the shape of the cable main body 10, etc., it can change suitably. Since the biting prevention part 22 is interposed between the biting inducement part 21 and the cable body 10, the rodent animal hits the bite induction part 21 and the bite induction part 21 is damaged over time. However, the teeth of rodents are stopped by the biting prevention unit 22. Therefore, it is possible to effectively prevent the cable body 10 from being bitten.
More preferably, the tensile strength of the biting prevention unit 22 is set to 50 MPa or more. Thereby, it is possible to reliably prevent the cable body 10 from being bitten.
Examples of the raw material of the biting prevention unit 22 include various metal materials such as SUS, iron, copper, copper alloys, and aluminum alloys, hard resin materials such as nylon and rigid PVC, or high-strength fibers such as aramid fibers (nonmetal). Fibre-based materials) are preferred.

  For example, the biting prevention unit 22 has a configuration in which two halves formed by injection molding of a metal material or a hard resin material are fitted and fixed to the outer periphery of the cable body 10. Further, for example, the biting prevention unit 22 has a configuration in which a tape made of a metal material (for example, SUS tape) or a plain weave tape of high-strength fiber is attached to the outer periphery of the cable body 10 spirally, laterally or vertically Have Alternatively, the biting prevention part 22 may be formed by winding a braided wire (wire mesh) made of a metal material or a hard resin material around the outer periphery of the cable body 10.

The external body 20 for biting may be mounted after the cable body 10 is laid, or may be mounted while the cable body 10 is being unwound from the drum at the time of laying. Further, when the cable 1 is manufactured, it may be attached to the cable body 10.
Further, the external body for biting 20 (the biting inducement part 21 and the biting prevention part 22) has a configuration in which two half pipes are fixed with bolts, or is attached to the cable body 10 with a clearance. For example, if the mounting position can be changed with respect to the cable body 10, it is preferable because it can flexibly cope with the actual biting situation.

By the way, in a cable track laid indoors and outdoors, biting by rodents does not occur uniformly in the longitudinal direction. For example, in the case of a cable track laid outdoors, the cable area in the manhole or the activity area of the rodents near the building and the passage area is susceptible to biting. Moreover, if it is a cable track laid indoors, the cable area | region near the passage of rodents, such as the vicinity of a cable passage hole, is easy to receive a bite. In addition, the state of biting by rodents varies depending on the density, type, and size of the rodents that inhabit them.
In addition, when a rodent is selected, a rodent animal is considered to concentrate on a certain area after trying to bite a certain area and determining an easy-to-crack part.

  Therefore, the ratio P / L1 of the mounting pitch (distance between adjacent biting outer bodies 20 and 20) P and the length L1 of the biting outer body 20 (biting attraction part 21) of the biting outer body 20 Need not be constant in the longitudinal direction, and may be set as appropriate according to the assumed biting environment. Thereby, the biting countermeasure cost can be reduced. For example, P / L1 may be reduced in areas where rodents live abundantly or are susceptible to bite, and P / L1 may be increased in areas other than that, or the external body 20 for biting may not be attached. .

  Further, when the cable 1 is laid, a portion that is susceptible to biting is predicted, and the bite by the rodent from the beginning of the cable laying is performed by installing the biting exterior body 20 in an optimal form. Can be effectively prevented. In addition, after laying the cable, the external body 20 for biting may be appropriately concentrated according to the biting situation while observing the biting situation to the biting invitation part 21. As described above, if the biting exterior body 20 is movable or detachable in the longitudinal direction with respect to the cable body 10, the mounting position of the biting exterior body 20 can be easily changed. .

  Further, in a region where rodent animals are considered to bite on trial, if the mounting pitch P of the biting outer body 20 is set to 0.1 to 1 m, the biting outer body 20 can be applied to the rodent animals. The existence is surely recognized (enters the rodent's view), so it is effective in combating bite.

The dimensions of the external body 20 for biting, that is, the length L1 and thickness of the bite attracting part 21, and the length L2 and thickness of the biting prevention part 22 are also set appropriately according to the assumed biting environment. Is done. For example, the greater the external body 20 for biting, the higher the resistance to biting, so that it is possible to effectively suppress biting on the cable body 10. However, if the external body 20 for biting is too large, the cost is increased and the workability is liable to deteriorate.
In particular, the outer diameter of the external body for biting 20 is considered to be 30 mm or less because it is considered that rodents are difficult to beat if it is too large. Moreover, about the bite inducement part 21, it is desirable to set length L1 to 2-20 cm and thickness to 1-10 mm in consideration of the conventional bite situation in a cable track.

In the cable 1, the rodent first crawls the biting inducement 21, and starts to beat from the end of the bite inducement 21. This is because the teeth are caught on the end portion (step) of the bite attracting portion 21 and are easily beaten. If the end face in the longitudinal direction of the biting prevention part 22 is flush with the end face of the biting inducement part 21, there is a concern that the cable main body 10 may be bitten at the beginning of the turn.
Therefore, it is desirable that the biting prevention unit 22 be formed wide so as to protrude from both longitudinal ends of the biting inducement 21. For example, the length L2 of the biting prevention unit 22 is made 2 to 20 mm longer than the length L1 of the biting inducement 21 and protrudes by 1 to 10 mm from both ends in the longitudinal direction. Thereby, when the rodent animal begins to beat from the end of the biting inducement 21, it is possible to prevent the biting of the cable body 10.
The thickness of the bite prevention unit 22 is not particularly limited as long as the bite of the rodent animal does not reach the cable body 10 located inside the bite prevention unit 22.

As described above, the cable 1 according to the embodiment includes the cable body 10 in which the jacket 12 is formed on the outer periphery of the cable core 11, and the bite inducing portion 21 having a smaller tensile strength than the jacket 12. And an external body for biting 20 that is intermittently attached to the outer periphery of the main body 10 in the longitudinal direction. That is, the external body 20 for biting which has the bite attracting part 21 which is easier to beat than the cable main body 10 for rodents is intermittently attached to the outer periphery of the cable main body 10 in the longitudinal direction.
According to the cable 1, compared with the conventional method in which the dummy cable is arranged along the longitudinal direction uniformly adjacent to the cable body 10, an extremely simple and inexpensive part of the external body for biting 20 is used to prevent biting. Can be realized. Moreover, since the special material for fenders is not kneaded by the outer cover 12 and the outer cover 12 is not modified, workability and safety at the time of laying the cable can be improved.

As mentioned above, although the invention made by this inventor was concretely demonstrated based on embodiment, this invention is not limited to the said embodiment, It can change in the range which does not deviate from the summary.
For example, in the embodiment, the biting attraction part 21 and the biting prevention part 22 constitute the biting exterior body 20, but the biting prevention part 22 is omitted and the biting induction part 21 is directly connected to the cable body. Even if it attaches to 10, the effect which suppresses the biting to the cable main body 10 by the rodent animal is acquired.

  In the embodiment, the case where the cable main body is configured by a slot-type optical fiber cable has been described. However, the present invention can be applied to a case where the cable main body has a configuration in which a jacket is formed on the outer periphery of the cable core. . That is, it can be applied to a wide range of cables that can be bitten by rodents, such as slotless optical fiber cables, metal communication cables, or power cables.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Cable 10 Cable main body 11 Cable core 111 Slot rod 111a Slot 112 Optical fiber tape core wire 113 Press-wound tape 114 Tension member 12 Outer jacket 20 Occlusion exterior body 21 Occlusion induction part 22 Occlusion prevention part

Claims (6)

A cable body having a jacket formed on the outer periphery of the cable core;
An occlusion-inducing portion having a tensile strength smaller than that of the outer sheath, and an occlusion-preventing portion that is interposed between the attraction-inducing portion and the cable body, and has a tensile strength larger than the tensile strength of the outer sheath. And an external body for biting that is intermittently mounted in the longitudinal direction on the outer periphery of the cable body ,
The cable according to claim 1, wherein the biting prevention part is formed so as to protrude from an end surface of the biting inducement part .   The cable according to claim 1, wherein a tensile strength of the bite inducement part is 50% or less of a tensile strength of the jacket.   The cable according to claim 1 or 2, wherein a tensile strength of the bite inducement part is 1 MPa or more and 30 MPa or less. The tensile strength of the said biting prevention part is 50 Mpa or more, The cable as described in any one of Claims 1-3 characterized by the above-mentioned. The cable according to any one of claims 1 to 4 , wherein the biting prevention unit is made of any one of a metal-based material, a non-metallic fiber-based material, and a resin-based material. . The cable according to any one of claims 1 to 5 , wherein an attachment position of the external body for biting can be changed with respect to the cable main body .

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