Protective article

Abstract

A protective article (1) for protecting a cable includes: an inner tube for accommodating the cable; an outer wall part for accommodating the inner tube; and a protective material (13) installed in a gap between the outer wall part and the inner tube and extending along the direction in which the cable extends. The protective material (13) has an end surface facing an end surface of a protective material (13') provided on a protective article (1') adjacent to the protective article (1) in said direction. At least a part of the end surface of the protective material (13) is not perpendicular to said direction.

Description

protective equipment

[0001] The present disclosure relates to protective articles.

[0002] Conventionally, conduits accommodating various cables have been buried shallow underground. Protective devices installed inside the conduits are known to protect the cables inside the conduits from damage caused by pavement cutters and the like used in road construction. For example, Patent Document 1 discloses an inner pipe inserted inside the conduit, an outer pipe accommodating the inner pipe, and a protective member installed between the inner pipe and the outer pipe.

[0003] International Publication No. 2024 / 042622

[0004] One possible approach is to equip the protective element with a tube containing a coloring agent to visually detect the presence of a pipeline when the paving cutter contacts the pipeline. Another possible approach is to equip the protective element with a buffer material to tactilely detect the presence of the pipeline and stop cutting when the paving cutter contacts the pipeline. However, inside the pipeline, adjacent protective elements may not be installed completely in close contact with each other to accommodate for bending of the pipeline, etc. In this case, gaps may form between the protective elements. If the paving cutter enters the gap, the worker will not be able to tactilely or visually detect the presence of the pipeline, and the protective elements may not be able to perform their function of protecting the cable. Figure 8A shows protective elements PM1 and PM2 installed adjacent to each other in the axial direction of the pipeline P inside the pipeline P. Figure 8B shows a cross-section of protective element PM1. Each of the protective items PM1 and PM2 includes three inner pipes I that house the cables C, one outer pipe O, a protective member M, and a tube T that houses a coloring agent. If the pavement cutter CT advances in the direction indicated by the white arrow in Figure 8A and enters the gap between the protective items PM1 and PM2, the protective function of the protective member M or the tube T will not be exerted, and the worker may unknowingly continue to advance the pavement cutter CT and cut the cables C. There is room for improvement in technology for protecting cables housed in conduits.

[0005] SUMMARY OF THE INVENTION An object of the present disclosure is to improve the technology for protecting cables housed in conduits.

[0006] In one embodiment, a protective item is a protective item for protecting a cable, and comprises: an inner tube for accommodating the cable; an outer wall portion for accommodating the inner tube; and a protective material installed in the gap between the outer wall portion and the inner tube and extending along the direction in which the cable extends, wherein the protective material has an end face opposite to an end face of a protective material provided on a protective item adjacent to the protective item along the direction, and at least a portion of the end face of the protective material is non-perpendicular to the direction.

[0007] According to an embodiment of the present disclosure, techniques for protecting cables housed in conduits can be improved.

[0008] FIG. 1 is a diagram illustrating a configuration example of a protective item inserted into a pipeline. FIG. 2 is a diagram illustrating a configuration example of a protective item inserted into a pipeline. FIG. 3 is a diagram illustrating a protective material and a tube viewed from an angle. FIG. 4 is a cross-sectional view of the protective material and the tube. FIG. 5 is a diagram illustrating an end face of the protective material. FIG. 6 is a diagram illustrating an end face of the protective material. FIG. 7 is a diagram illustrating an end face of the protective material. FIG. 8 is a diagram illustrating an end face of the protective material. FIG. 9 is a diagram illustrating an end face of the tube. FIG. 10 is a diagram illustrating a protective item of a comparative example. FIG. 11 is a diagram illustrating a protective item of a comparative example.

[0009] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, parts having the same configuration or function are denoted by the same reference numerals. In the description of this embodiment, duplicated descriptions of the same parts may be omitted or simplified as appropriate.

[0010] An overview of this embodiment will be described with reference to FIGS. 1A and 1B . FIG. 1A shows an end face of a protective element 1 inserted into a pipeline P. FIG. 1B is a view of the protective element 1, a protective material 13 and a tube 14 provided in the protective element 1, a protective element 1' adjacent to the protective element 1, and a protective material 13' and a tube 14' provided in the protective element 1', viewed from a direction perpendicular to the axial direction of the pipeline P. The protective element 1 is for protecting a cable 2. The protective element 1 includes an inner pipe 11 for accommodating the cable 2, an outer wall portion 12 for accommodating the inner pipe 11, and a protective material 13 installed in a gap S between the outer wall portion 12 and the inner pipe 11 and extending along the direction in which the cable 2 extends. The protective material 13 has an end face 131 facing a protective material 13' provided in a protective element 1' adjacent to the protective element 1 along that direction. At least a portion of an end surface 131 of the protective material 13 is non-perpendicular to the direction in which the cable 2 extends. The protective article 1 further includes a tube 14 that contains a colorant, has lower strength than the outer wall portion 12, is installed in the gap S, and extends along the direction in which the cable 2 extends. The tube 14 has an end surface 141 that faces the tube 14' provided in the protective article 1'. Like the end surface 131 of the protective material 13, at least a portion of the end surface 141 of the tube 14 is also non-perpendicular to the direction in which the cable 2 extends.

[0011] The pipeline P is buried underground. At the position indicated by the solid arrow in FIG. 1B , a gap may occur between the protective material 13 and the tube 14 of the protective device 1 and the protective material 13' and the tube 14' of the protective device 1'. When the pavement cutter CT advances from outside the pipeline P in the direction indicated by the white arrow in FIG. 1B and enters this gap, the pavement cutter CT hits at least one of the protective material 13 and the tube 14. When the pavement cutter CT hits the protective material 13, the worker receives a recoil caused by the pavement cutter CT hitting the protective material 13 and can force-sense that the pavement cutter CT is hitting the pipeline P. When the pavement cutter CT hits the tube 14, the tube 14 is broken by the pavement cutter CT, and the coloring agent contained in the tube 14 is released, allowing the worker to visually sense that the pavement cutter CT is hitting the pipeline P. Force or visual detection can reduce the possibility that a worker will unknowingly advance the pavement cutter CT and cut the cable 2 inside the protective element 1. This improves the technology for protecting cables housed in conduits.

[0012] The configuration of the protective article 1 will be described in detail with reference to FIGS. 1A to 7B.

[0013] The inner pipe 11 is installed inside the outer wall portion 12 and accommodates the cables 2. The number of cables 2 accommodated in one inner pipe 11 is not limited to one, two, or three as shown in FIG. 1A , but may accommodate, for example, four or more cables. As shown in FIG. 1A , the cables 2 accommodated in the inner pipe 11 may have different diameters. While the number of inner pipes 11 is three in the example shown in FIG. 1A , the number may be less than three or four or more. While the inner pipe 11 shown in FIG. 1A has a circular cross section, the inner pipe 11 may also have a rectangular cross section. The inner pipe 11 is made of a synthetic resin material such as rigid polyvinyl chloride, polyethylene, polypropylene, or ABS (acrylonitrile butadiene rubber styrene), or a metal material including steel.

[0014] The outer wall 12 accommodates the inner tube 11. While the outer wall 12 shown in Fig. 1A has a circular cross section, the outer wall 12 may have a rectangular cross section. The outer wall 12 is made of a synthetic resin material such as rigid polyvinyl chloride, polyethylene, polypropylene, or ABS, or a metal material including steel.

[0015] The protective materials 13 are provided in gaps S formed by the outer surfaces of each of two circumferentially adjacent inner pipes 11 of the pipeline P and the inner surface of the outer wall portion 12. The protective materials 13 are made of a hard material such as ceramic or metal. Referring to FIG. 1A , a protective material 13 is provided in each of the three gaps S, but the number of protective materials 13 is not limited to this. The protective materials 13 have end faces 131 that face adjacent protective materials 13′ in the axial direction of the pipeline P. In FIG. 1A , each end face 131 of the protective materials 13 has a pentagonal shape, but the shape of the end faces 131 of the protective materials 13 is not limited to this.

[0016] The tube 14 is installed along the direction of extension of the outer wall 12 while being shielded by the outer wall 12. The tube 14 contains a colorant. The tube 14 has lower strength than the outer wall 12. The tube 14 is made of a material such as polyethylene, silicone, or polyvinyl chloride. This provides the tube 14 with flexibility, allowing the tube 14 to be accommodated in the gap S without wasting space while in contact with both the inner surface of the outer wall 12 and the outer surface of the inner pipe 11. The colorant for the tube 14 is a liquid made of any material, such as a pigment or paint. Alternatively, the colorant may be in powder form. The colorant has a high saturation color with a saturation equal to or greater than a predetermined value, specifically, may be red, yellow, white, or the like. This makes the colorant conspicuous when it comes into contact with the soil, concrete, or the like, allowing workers to easily notice it. The colorant may be sealed in the tube 14 at a pressure higher than atmospheric pressure. As a result, when the pavement cutter CT comes into contact with the tube 14 and the tube 14 breaks, the coloring agent inside the tube 14 is ejected to the outside. Referring to Fig. 1A, two tubes 14 are provided in each of the three gaps S, but the number of tubes 14 is not limited to this. The tube 14 has an end face 141 that faces the adjacent tube 14' in the axial direction of the pipeline P.

[0017] FIG. 2 is a perspective view of the protective element 1, the protective material 13 and the tube 14 provided inside the protective element 1, the protective element 1' adjacent to the protective element 1, and the protective material 13' and the tube 14' provided inside the protective element 1'. In this example, each protective element includes two protective elements and one tube. The length L1 of a single protective element 13 or protective element 13' is, for example, 80 mm. The length L2 of a single tube 14 or tube 14' is, for example, 160 mm. As another example, each protective element may include one protective element, and the length L1 of the protective element 13 may be the same as the length L2 of the tube 14. FIG. 2 shows a pavement cutter CT proceeding into the gap between the protective element 1 and the protective element 1'. It is assumed that the pavement cutter CT proceeds from above or diagonally above the pipe P in the vertical direction, perpendicular or at an angle to the X-axis direction, which is the direction in which the cable 2 extends.

[0018] The protective material 13 has an end face 131 that faces the protective material 13' included in the protective article 1'. The protective material 13' also has an end face 131' that faces the protective material 13. The tube 14 has an end face 141 that faces the tube 14' included in the protective article 1'. The tube 14' also has an end face 141' that faces the tube 14. FIG. 3 shows an enlarged view of the end face 131 of the protective material 13 and the end face 141 of the tube 14. As shown in FIG. 3, the tube 14 may have a substantially triangular end face 141 by being provided in close contact with the protective material 13 in the gap S.

[0019] Three examples of the shapes of end surface 131 and end surface 131' will be described with reference to Figures 4A to 6B. Figures 4A, 5A, and 6A are views of protective material 13 and protective material 13' at the positions of the white arrows in Figure 2, viewed from the Z-axis direction. Figures 4B, 5B, and 6B are views of protective material 13 and protective material 13' at the positions of the white arrows in Figure 2, viewed from the Y-axis direction.

[0020] A first example will be described with reference to Figures 4A and 4B. Referring to Figure 4B, the end surface 131 of the protective material 13 is non-perpendicular to the X-axis direction, which is the direction in which the cable 2 extends, and is entirely inclined with respect to the X-axis direction so that the upper edge portion 131OE protrudes to one side in the X-axis direction. The end surface 131' of the protective material 13' is also non-perpendicular to the X-axis direction, but is entirely inclined with respect to the X-axis direction so that the lower edge portion 131E' protrudes to the other side in the X-axis direction. The dashed line in Figure 4A indicates the position of the lower edge portion 131E' of the end surface 131'. The shape of the end surface of the protective material 13 opposite the end surface 131 when viewed from the Y-axis direction may be similar to the shape of the end surface 131' of the protective material 13' shown in Figure 4B. The shape of the end surface of the protective material 13' opposite the end surface 131' when viewed from the Y-axis direction may be similar to the shape of the end surface 131 of the protective material 13 shown in Figure 4B.

[0021] A second example will be described with reference to Figures 5A and 5B. Referring to Figure 5A, the end surface 131 of the protective material 13 is non-perpendicular to the X-axis direction, which is the direction in which the cable 2 extends, and includes a protrusion PT1 that protrudes to one side in the X-axis direction. The protrusion PT1 has an acute angle in a plan view from the Z-axis direction. The end surface 131 may include two or more protrusions PT1. The end surface 131' of the protective material 13' is also non-perpendicular to the X-axis direction, but includes a recess RC1 that is recessed to the other side in the X-axis direction to correspond to the protrusion PT1. The dashed line in Figure 5B indicates the position of the tip of the protrusion PT1. In this example, the end surfaces 131 and 131' are perpendicular to the direction in which the cable 2 extends in an elevation view from the Y-axis direction. However, this is not limited to this. As in Figure 4B, the end surfaces 131 and 131' may be non-perpendicular to the direction in which the cable 2 extends and may be inclined as a whole. The shape of the end face of the protective material 13 opposite to the end face 131 when viewed from the Z-axis direction may be the same as the shape of the end face 131' of the protective material 13' shown in Fig. 5A. The shape of the end face of the protective material 13' opposite to the end face 131' when viewed from the Z-axis direction may be the same as the shape of the end face 131 of the protective material 13 shown in Fig. 5A.

[0022] A third example will be described with reference to FIGS. 6A and 6B. Referring to FIG. 6A, the end surface 131 of the protective material 13 is non-perpendicular to the X-axis direction, which is the direction in which the cable 2 extends, and includes a protrusion PT2 protruding to one side in the X-axis direction. The protrusion PT2 is arc-shaped. This is not a limitation, and the protrusion PT2 may be a convex portion curved in any shape. The end surface 131 may include two or more protrusions PT2. The end surface 131' of the protective material 13' is also non-perpendicular to the X-axis direction, but includes a recess RC2 recessed to the other side in the X-axis direction to correspond to the protrusion PT2. The dashed line in FIG. 6B indicates the position of the tip of the protrusion PT2. In this example, the end surfaces 131 and 131' are perpendicular to the direction in which the cable 2 extends when viewed from the Y-axis direction. However, this is not a limitation, and the end surfaces may be non-perpendicular to the direction in which the cable 2 extends, and may be inclined as a whole, as in FIG. 4B. The shape of the end face of the protective material 13 opposite to the end face 131 when viewed from the Z-axis direction may be the same as the shape of the end face 131' of the protective material 13' shown in Fig. 6A. The shape of the end face of the protective material 13' opposite to the end face 131' when viewed from the Z-axis direction may be the same as the shape of the end face 131 of the protective material 13 shown in Fig. 6A.

[0023] 4A to 6B or from a direction angled toward the arrow, the pavement cutter CT will hit the protective material 13 or the protective material 13' because at least a portion of the end face 131 and the end face 131' in each of the above examples is not perpendicular to the extension direction of the cable 2. When the pavement cutter CT hits the protective material 13 or the protective material 13', a repulsive force is generated, which reduces the cutting speed of the pavement cutter CT, allowing the worker to sense with force that the pavement cutter CT is hitting the pipeline P.

[0024] Examples of end surfaces 141 and 141' will be described with reference to Figures 7A and 7B. Figure 7A is a view of tube 14 and tube 14' at the positions of the white arrows in Figure 2, viewed from the Z-axis direction. Figure 7B is a view of tube 14 and tube 14' at the positions of the white arrows in Figure 2, viewed from the Y-axis direction.

[0025] Referring to FIG. 7B , the end face 141 of the tube 14 is non-perpendicular to the X-axis direction, which is the direction in which the cable 2 extends, and is entirely inclined relative to the X-axis direction so that the upper edge portion 141OE protrudes to one side in the X-axis direction. The end face 141' of the tube 14' is also non-perpendicular to the X-axis direction, but is entirely inclined relative to the X-axis direction so that the lower edge portion 141E' protrudes to the other side in the X-axis direction. The dashed line in FIG. 7A indicates the position of the lower edge portion 141E' of the end face 141'. The shape of the end face of the tube 14 opposite the end face 141 when viewed from the Y-axis direction may be similar to the shape of the end face 141' of the tube 14'. The shape of the end face of the tube 14' opposite the end face 141' when viewed from the Y-axis direction may be similar to the shape of the end face 141 of the tube 14.

[0026] The end surface 141 of the tube 14 and the end surface 141' of the tube 14' may have a shape similar to the end surface 131 of the protective material 13 and the end surface 131' of the protective material 13' shown in FIGS. 5A to 6B.

[0027] 7A and 7B , the pavement cutter CT will hit the tube 14 or 14' because at least a portion of the end face 141 and end face 141' in the above example is not perpendicular to the extension direction of the cable 2. When the pavement cutter CT hits the tube 14 or 14', the tube 14 or 14' breaks, releasing the coloring agent, allowing the worker to visually detect that the pavement cutter CT is hitting the pipeline P.

[0028] The protective device 1 is installed in the pipeline P by being inserted from the end of the pipeline P. Specifically, a worker may enter a manhole and insert and install the protective device 1 from the end of the pipeline P that is exposed in the manhole. The worker may install multiple protective devices 1 by sequentially pushing multiple protective devices 1 into the inside of the pipeline P.

[0029] The following additional notes are provided regarding the above-described embodiments.

[0030] (Supplementary Item 1) A protective item for protecting a cable, comprising: an inner tube for accommodating the cable; an outer wall portion that accommodates the inner tube; and a protective material that is placed in a gap between the outer wall portion and the inner tube and extends along the direction in which the cable extends, the protective material having an end face that faces an end face of a protective material provided on a protective item adjacent to the protective item along the direction, and at least a portion of the end face of the protective material is non-perpendicular to the direction. (Supplementary Item 2) The protective item according to Supplementary Item 1, further comprising: a tube that contains a colorant and has lower strength than the outer wall portion, that is placed in the gap and extends along the direction, the tube having an end face that faces an end face of a tube provided on the adjacent protective item, and at least a portion of the end face of the tube is non-perpendicular to the direction. (Supplementary Item 3) The protective item according to Supplementary Item 1 or 2, wherein the end face of the protective material is inclined as a whole. (Supplementary Item 4) The protective item according to any one of Supplementary Items 1 to 3, wherein the end face of the protective material has a convex portion that protrudes in the direction.

[0031] The present disclosure is not limited to the above-described embodiments, and the configurations shown in the drawings can be modified without departing from the spirit of the present disclosure.

[0032] 1, 1' Protective item 11 Inner pipe 12 Outer wall portion 13, 13' Protective material 14, 14' Tube 131, 131' End face 141, 141' End face 2 Cable

Claims

1. A protective item for protecting a cable, comprising: an inner tube for accommodating the cable; an outer wall portion for accommodating the inner tube; and a protective material installed in the gap between the outer wall portion and the inner tube and extending along the direction in which the cable extends, wherein the protective material has an end face that faces an end face of a protective material provided on a protective item adjacent to the protective item along the direction, and at least a portion of the end face of the protective material is non-perpendicular to the direction.

2. A protective article according to claim 1, further comprising a tube containing a colorant and having a strength lower than that of the outer wall portion, the tube being installed in the gap and extending along the direction, the tube having an end face opposing an end face of a tube provided in the adjacent protective article, and at least a portion of the end face of the tube being non-perpendicular to the direction.

3. A protective article according to claim 1 or 2, wherein the end face of the protective material is entirely inclined.

4. A protective article according to claim 1 or 2, wherein the end face of the protective material has a convex portion that protrudes in the direction.

Images