JP7684686B2 - protection tube - Google Patents

Description

The present invention relates to a protective tube that covers and protects a linear object such as a cable.

Traditionally, cables laid or buried on the seabed have been used as communication or power transmission lines between islands. Such cables are generally covered and protected by protective tubes to prevent damage caused by contact with reefs and other objects caused by being carried away by ocean currents or waves, or by contact with the bottoms of passing ships or anchors lowered from ships.

Such a protective tube is formed, for example, into a cylindrical shape consisting of a pair of half-pipes arranged opposite each other. To attach the protective tube to the cable, a pair of half-pipes are arranged to cover the sides of the cable from one side and the other, and these half-pipes are fixed to each other with bolts (see, for example, Patent Document 1).

JP 2007-209107 A

However, with the protective pipe described above, the task of fastening a pair of half-pipe bodies together with bolts requires a great deal of work, and it cannot be said that workability is good. For example, in environments with low seawater transparency, such as muddy or sludge-filled seabeds, workers underwater may be forced to work almost entirely by hand, which can make it difficult to screw in the bolts.

The present invention aims to solve the above problems by providing a protective tube that can be easily attached to a linear object such as a cable and has good workability.

The present invention is a protective tube formed by arranging a pair of half-split pipe bodies so that the concave sides of the half-split pipe bodies face each other, the half-split pipe bodies having a straight pipe section formed in a semi-cylindrical shape, a bulging section provided at the rear end of the straight pipe section and having a larger diameter than the straight pipe section, a connecting section provided at the front end of the straight pipe section and connecting with the bulging section of the other protective tube, and an engaging section provided on the outer periphery of the connecting section and engaging the pair of half-split pipe bodies with each other, the engaging section having a protruding piece provided at one installation end of the half-split pipe body and a recessed section provided at the other installation end into which the protruding piece fits, The protruding pieces protrude in opposing directions toward the paired half-pipe body, and are bent forward at a predetermined curvature toward their tips, and the recessed portion is bent at the same curvature as the protruding piece at the contact portion, and the protruding piece engages with the recessed portion by fitting the tip of the protruding piece into the recessed portion and rotating the pair of half-pipe bodies so that the straight pipe portions approach each other, and the contact portion of the protruding piece and the recessed portion is formed in an arc shape, with the center of the arc being located forward of the front end of the half-pipe body.

The recess is formed by being sandwiched between a front support provided in front of the recess and a rear support provided behind the recess, and the rear support has a leg piece protruding in the opposing direction, and when multiple half-pipes are stacked in multiple tiers in the same orientation, it is preferable that the tip of the leg piece and the tip of the protruding piece of the half-pipe of the upper tier are placed on the base end of the rear support and the base end of the protruding piece of the half-pipe of the lower tier.

It is preferable that the protruding piece has a recess at its base end to hold the tip of the protruding piece of the half pipe body placed on the upper stage.

It is preferable that the pair of half pipes have the same shape.

The protective tube of the present invention allows a pair of half-pipes to be engaged with each other by a simple rotation operation, making it easier to attach to the cable and easier to work with than when engaging them by screwing in a bolt.

FIG. 2 is an exploded perspective view of a protective tube according to an embodiment of the present invention. 4A is a side view of a half pipe body constituting the protective pipe, as viewed from the protruding one side, and FIG. 4B is a side view of the half pipe body, as viewed from the recessed portion side. FIG. FIG. 4 is a perspective view showing a state in which a plurality of the protective tubes are connected in a straight line. 5A and 5B are side views showing the operation of connecting a plurality of the protective tubes to each other. 6A and 6B are other side views showing the operation of connecting a plurality of the protective tubes to each other. 1A is a side view of a half pipe according to a comparative example, as viewed from the protruding one side, and FIG. 1B is a side view of the half pipe as viewed from the recessed portion side. 6A and 6B are side views showing an operation for connecting a plurality of protective tubes according to the comparative example to each other. 1A is an oblique view showing a state in which multiple half pipe bodies are stacked, FIG. 1B is a side view of the half pipe body seen from the protruding side, FIG. 1C is a side view of the half pipe body seen from the recessed portion side, and FIG. 1D is a view of the half pipe body seen from the front. FIG. 11 is an exploded perspective view of a protective tube according to a modified example of the embodiment. 10A is a side view of a half pipe body constituting a protective pipe according to the above modified example, seen from a protruding one side, and FIG. 10B is a side view of the half pipe body, seen from a recessed portion side. 1A is an oblique view showing a state in which multiple half-pipe bodies relating to the above-mentioned modified example are stacked, FIG. 1B is a side view of the same half-pipe body seen from the protruding side, FIG. 1C is a side view of the same half-pipe body seen from the recessed portion side, and FIG. 1D is a view of the same half-pipe body seen from the front.

A protective tube according to one embodiment of the present invention will be described with reference to Figs. 1 to 9. As shown in Fig. 1, the protective tube 1 is formed into a generally cylindrical shape as a whole and is composed of a pair of half-split pipes 2, 2 that are split in half at a plane including the cylindrical axis. The half-split pipes 2, 2 have the same shape and are arranged so that their concave surfaces 20 face each other to cover the side circumference of a linear body such as a cable C from two directions. The pair of half-split pipes 2, 2 abut at the end surfaces (arrangement ends 21, 22) that form both ends of the concave surface 20. Note that, although the linear body is a single cable C with a circular cross section in the illustrated example, it may be, for example, multiple cables, a cable with an elliptical or flat cross section, or a water pipe or a gas pipe.

Each half-split pipe 2 has a straight pipe section 3 formed in a semi-cylindrical shape along the side circumference of the cable C, a bulge section 4 provided at one end (hereinafter referred to as the rear end) of the straight pipe section 3 in the cylindrical axial direction, and a connecting section 5 provided at the other end (hereinafter referred to as the front end) of the straight pipe section 3 in the cylindrical axial direction. The bulge section 4 has a structure with a larger diameter than the straight pipe section 3, and is constituted by a flange in the illustrated example. The connecting section 5 is formed in a bag shape with a larger diameter than the straight pipe section 3, for example, a semi-cylindrical or semi-spherical shape, and is connected to the bulge section 4 of another protective pipe 1 as described below.

Each half-pipe 2 has an engagement portion 6 provided on the outer periphery of the connecting portion 5 to engage the pair of half-pipe 2, 2 with each other. The engagement portion 6 has a protruding piece 61 provided on one installation end 21 of the half-pipe 2 near the connecting portion 5, and a recessed portion 62 provided on the other installation end 22 into which the protruding piece 61 fits. The protruding piece 61 is formed as a piece that protrudes in the opposing direction D toward the paired half-pipe 2. The recessed portion 62 is formed by being sandwiched between a front receiving portion 63 provided in front of the recessed portion 62 and a rear receiving portion 64 provided behind the recessed portion 62.

The half pipe bodies 2, 2 also have bolt fixing parts 7 for fixing the half pipe bodies 2, 2 to each other with bolts (not shown). The bolt fixing parts 7 are provided at the installation end parts of the straight pipe parts 3 adjacent to the rear end of the connecting part 5, and are formed in a piece shape extending from the outer periphery of the straight pipe parts 3 in a direction perpendicular to both the cylindrical axial direction of the straight pipe parts 3 and the facing direction D. The bolt fixing parts 7 have bolt holes 71 for inserting a bolt along the facing direction D.

As shown in FIG. 2(a), the protruding piece 61 is bent forward at a predetermined curvature toward its tip 61a. The contact portions 61b, 61c of the protruding piece 61 that contact the recessed portion 62 are formed in an arc shape, and the center O of the arc is located forward of the front end of the half-split pipe body 2. As shown in FIG. 2(b), the contact portions 62a, 62b of the recessed portion 62 that contact the protruding piece 61 are bent at the same curvature as the protruding piece 61, and are formed in an arc shape centered on the center O.

The rear receiving portion 64 has a leg piece 65 that protrudes in the facing direction D. The protruding height of the leg piece 65 in the facing direction D is lower than the protruding height of the protruding piece 61 in the facing direction D. Note that in FIG. 2(a), the leg piece 65 located at the back of the paper is hatched with a dot pattern, and in FIG. 2(b), the protruding piece 61 located at the back of the paper is hatched.

As shown in FIG. 3, the connecting portion 5 has an expanded diameter portion 51 that is expanded to have an inner diameter R2 larger than the outer diameter R1 of the bulge portion 4, and a reduced diameter portion 52 that is provided at the front end of the expanded diameter portion 51 and has an inner diameter R3 smaller than the outer diameter R1 of the bulge portion 4. As a result, as shown in FIG. 4, when multiple protective tubes 1 are arranged so that the expanded diameter portion 51 of one protective tube 1a includes the bulge portion 4 of the adjacent protective tube 1b, the movement of the bulge portion 4 in the front-rear direction is restricted by the reduced diameter portion 52 and the straight tube portion 3, and multiple protective tubes 1 can be connected in a straight line without the protective tube 1b being displaced in the front-rear direction relative to the protective tube 1a.

At this time, as shown in Fig. 5(a), in order to engage a half-split pipe 2a on one side of a cable C (the upper side in the illustrated example) in one protective tube 1a with a half-split pipe 2b on the other side of the cable C (the lower side in the illustrated example), first, the half-split pipe 2b is positioned so that the expanded diameter portion 51 of the half-split pipe 2b includes the bulged portion 4 of the adjacent protective tube 1b in front. Then, the tip 61a of the protruding piece 61 of the half-split pipe 2a is fitted into the recessed portion 62 of the half-split pipe 2b, and the half-split pipes 2a and 2b are rotated around the circular center O as the rotation center so that the straight pipe portions 3 of each approach each other. Then, because the contact portions 61b, 61c of the protruding piece 61 and the contact portions 62a, 62b of the recessed portion 62 are formed with the same curvature, the protruding piece 61 fits into the recessed portion 62, and the half pipes 2a, 2b engage with each other, as shown in FIG. 5(b).

Here, the circular center O of the protective tube 1 is located forward of the front end of the half-pipe body 2. Therefore, as shown in FIG. 6(a), even if the cable C is curved, the tip 61a of the protruding piece 61 of the half-pipe body 2a can fit into the recessed portion 62 of the half-pipe body 2b to the extent that the reduced diameter portion 52 of the protective tube 1a does not interfere with the straight pipe portion 3 of the protective tube 1b. As a result, as shown in FIG. 6(b), even if the protective tube 1b is at an angle to the protective tube 1a, the protruding piece 61 engages with the recessed portion 62, so that even a curved cable C can be protected by the protective tubes 1a and 1b.

Here, a comparative example will be described in comparison with the protective tube 1 of this embodiment (Example). In Fig. 7 (a) and (b), the shape of the Example is shown by a solid line, while the shape of the Comparative Example is shown by a dashed line. In the Comparative Example (dashed line), the arc shape of the abutting parts 61b', 61c' of the protruding piece 61' and the abutting parts 62a', 62b' of the recessed part 62' is bent forward more than that of the Example (solid line). As a result, the rotation radius of the half-split pipe body 2 is smaller, and the circle center P of the Comparative Example is located rearward compared to the circle center O of the Example (see Fig. 2 (a) and (b)) (the circle center P of the illustrated example is located at the front end of the half-split pipe body 2). In Fig. 7 (a) and (b), the leg piece 65 (Example) located at the back of the paper and the protruding piece 61' (Comparative Example) located at the back of the paper are indicated by hatching with a dot pattern.

When using such a half pipe 2' according to the comparative example to cover a curved cable C, as shown in Fig. 8(a), when the half pipes 2a' and 2b' are rotated so that the straight pipe sections 3 of each of them approach each other around the circle center P as the rotation center, the reduced diameter section 52 of the protective pipe 1a' interferes with the straight pipe section 3 of the protective pipe 1b'. Therefore, in reality, as shown in Fig. 8(b), the half pipes 2a' and 2b' cannot be brought into contact with each other through their front ends due to the interference between the reduced diameter section 52 of the protective pipe 1a' and the straight pipe section 3 of the protective pipe 1b'. In this state, the tip 61a' of the protruding piece 61' of the half pipe 2a' hits the front receiving section 63' of the half pipe 2b' and cannot fit into the recessed section 62', and the half pipes 2a and 2b' cannot be engaged with each other. That is, as in the embodiment shown in FIG. 6(a), by positioning the circle center O forward of the front end of the half pipe body 2, the pair of half pipe bodies 2a and 2b can be engaged even if the cable C is curved.

As shown in FIG. 9(a), multiple half pipes 2 are stored stacked in multiple tiers in the same orientation with their straight pipe sections 3 overlapping each other. At this time, as shown in FIG. 9(b), the tip 61a of the protruding piece 61 of the upper half pipe 2a is placed on the base end 61d of the protruding piece 61 of the lower half pipe 2b adjacent to the half pipe 2a. Also, as shown in FIG. 9(c), the tip 65a of the leg piece 65 of the half pipe 2a is placed on the base end 64a of the rear support portion 64 of the half pipe 2b. This allows multiple half pipes 2 to be stably stacked and stored in a space-saving manner, as shown in FIG. 9(d).

According to the protective tube 1 configured as described above, the pair of half pipes 2, 2 can be engaged with each other by a simple rotation operation, which allows for easier attachment to the cable C and improved workability compared to when the pair of half pipes are engaged with each other by screwing in a bolt. The pair of half pipes 2, 2 are engaged with sufficient strength by fitting each of the protruding pieces 61 into the recessed portion 62, but the half pipes 2, 2 may be engaged with each other more securely by screwing a nut onto a bolt passed through the bolt hole 71 of the bolt fixing portion 7 and tightening the bolt and nut. In addition, since the engaging portion 6 is provided on the outer periphery of the connecting portion 5 and can be seen from the outside, the work of fitting the protruding piece 61 into the recessed portion 62 is easier than when the engaging portion 6 is provided on the inner periphery of the connecting portion 5.

In addition, when a pair of half pipes have different shapes, it is necessary to check the shape of each half pipe before engaging them with each other. However, in this embodiment, the pair of half pipes 2, 2 have the same shape, so such shape check is not necessary, improving workability. Furthermore, for example, when manufacturing the half pipe 2 by casting, it is only necessary to prepare one mold, which reduces costs.

Next, a protective tube according to a modified example of the above embodiment will be described with reference to Figs. 10 to 12. As shown in Fig. 10, the protective tube 10 is based on the above-mentioned protective tube 1, and the structure of the engagement portion 6 has been improved.

As shown in FIG. 11(a), in this modified example, a recess 61e is provided at the base end 61d of the protruding piece 61 to hold the tip 61a of the protruding piece 61 of the other half-pipe 2. Also, as shown in FIG. 11(b), the protruding height of the leg piece 65 in the facing direction D is equal to the protruding height of the protruding piece 61 in the facing direction D. Note that in FIG. 11(a), the leg piece 65 located toward the back of the page is hatched with a dot pattern, and in FIG. 11(b), the protruding piece 61 located toward the back of the page is hatched.

As shown in Figures 12(a)-(d), when multiple half-pipe bodies 2 are stacked in multiple tiers, the tip 61a of the protruding piece 61 of the upper half-pipe body 2a is held in the recess 61e of the protruding piece 61 of the lower half-pipe body 2b adjacent to the half-pipe body 2a (see Figure 12(b)). This makes it difficult for the half-pipe body 2a to shift in position in the front-rear direction relative to the half-pipe body 2b.

In addition, since the protruding height of the leg piece 65 and the protruding piece 61 in the facing direction D are equal, when multiple half-pipe bodies 2 stacked in multiple tiers are placed on a level ground G, the half-pipe bodies 2 do not tilt, and the half-pipe bodies 2 can be stacked stably (see FIG. 12(d)). In addition, the height of the rear end side of the half-pipe body 2 is set by placing the arrangement end parts 21, 22 of the concave surface 20 of the upper half-pipe body 2 on the bulging part 4 of the lower half-pipe body 2. On the other hand, the height of the front end side of the half-pipe body 2 is set by the height of the protruding piece 61 and the leg piece 65. And the height of the rear end side of the half-pipe body 2 and the height of the front end side are approximately equal. As a result, when the half-pipe bodies 2 are stacked in multiple tiers, the straight pipe section 3 is kept horizontal (see FIG. 12(b)).

The protective tube according to the present invention is not limited to the above embodiment and its modified examples, and various modifications are possible. For example, the engagement portion 6 in this embodiment is provided on the outer periphery of the connecting portion 5 on the front end side of the half-split pipe body 2, but some kind of engagement portion or fixing mechanism may also be provided on the bulging portion 4 side at the rear end. In addition, the positional relationship between the protruding piece 61 and the recessed portion 62 may be reversed on the left and right sides from that shown in the example. Furthermore, the bulging portion 4 is not limited to a flange, and may be formed, for example, in a semi-cylindrical or semi-spherical shape, similar to the connecting portion 5.

Reference Signs List 1, 1a, 1b, 10 Protective tube 2, 2a, 2b Half-pipe body 20 Concave surface 21, 22 Installation end 3 Straight pipe section 4 Bulging section 5 Connection section 6 Engagement section 61 Projecting piece 61a Tips 61b, 61c of projecting piece Abutting section 61d Base end 61e of projecting piece Recess 62 of projecting piece Depression sections 62a, 62b Abutting section 63 of depression section Front receiving section 64 Rear receiving section 64a Base end 65 of rear receiving section Leg piece 65a Tip D of leg piece Opposing direction O Center of circle

Claims (4)

A protective tube formed by arranging a pair of half pipes such that the concave sides of the half pipes face each other,
The half pipe body has a straight pipe section formed in a semi-cylindrical shape, a bulging section provided at a rear end of the straight pipe section and having a larger diameter than the straight pipe section, a connecting section provided at a front end of the straight pipe section and connecting to the bulging section of another of the protective pipes, and an engaging section provided on an outer periphery of the connecting section and engaging the pair of half pipe bodies with each other,
the engaging portion has a protruding piece provided at one installation end of the half pipe body and a recessed portion provided at the other installation end into which the protruding piece fits,
The protruding pieces protrude in opposing directions toward the paired half pipes, and are bent forward at a predetermined curvature toward the tip thereof,
the recessed portion has a contact portion with the protruding piece that is bent with the same curvature as the protruding piece,
The tip of the protruding piece is fitted into the recessed portion, and the pair of half pipe bodies is rotated so that the straight pipe portions approach each other, whereby the protruding piece engages with the recessed portion,
A protective tube characterized in that the abutment portion between the protruding piece and the recessed portion is formed in an arc shape, and the center of the arc is located forward of the front end of the half tube body. The recessed portion is formed by being sandwiched between a front receiving portion provided in front of the recessed portion and a rear receiving portion provided behind the recessed portion,
The rear receiving portion has a leg piece protruding in the opposing direction,
The protective tube described in claim 1, characterized in that when multiple half pipes are stacked in multiple tiers in the same orientation, the tip of the leg piece and the tip of the protruding piece of the half pipe of the upper tier are placed on the base end of the rear support part and the base end of the protruding piece of the half pipe of the lower tier. The protective tube according to claim 2, characterized in that the protruding piece has a recess at its base end that holds the tip of the protruding piece of the half-pipe body placed on the upper stage. 4. The protective tube according to claim 1, wherein the pair of half pipes have the same shape.