JP7142346B2 - Protective tube, protective tube manufacturing method, and protective tube component - Google Patents

Description

TECHNICAL FIELD The present invention relates to a protective tube for protecting electric wires such as high-voltage cables, a method for manufacturing the same, and parts of the protective tube.

Conventionally, there are protective tubes for protecting electric wires. Such protective pipes, through which electric wires are inserted, protect the passed electric wires from weathering due to rainfall and the like, and from damage due to scattering of substances from the outside. As such a protective tube, there is a metal wire pipe as described in Patent Document 1. In Patent Literature 1, a rectangular metal tube having a rectangular cross section is used as a protection tube, and an electric wire is inserted into the tube for protection. The protective pipe of Patent Document 1 has a curved portion in order to avoid interference with other pipes or the like.

As another protective pipe, there is a protective pipe which is arranged near a railroad track and through which an electric wire such as a high-voltage cable for supplying electric power to a train is inserted. Such protective pipes consist of metal tubes with square-shaped cross sections to prevent paving stones from scattering around the tracks and damaging the high-voltage cables when trains pass through the tracks. be. This protection tube has a curved portion that rises upward from the ground in response to the rise of the high-voltage cable.

These protective pipes having a curved portion are conventionally formed by a method such as applying a large force to forcibly bend a cylinder formed straight using a jig or the like.

JP-A-8-186919

However, if a jig or the like is used on a cylinder that is formed straight and a large force is applied to forcibly bend the protective tube, the degree of curvature of the curved portion is regulated by the jig. It will be done. Therefore, if an attempt is made to create protective tubes having different curvatures at the curved portions, it is necessary to prepare jigs for variations in curvature. In addition, when the protective tube is formed by forcibly bending the tube using a jig, there is a limit to the accuracy of the curvature of the curved portion. Therefore, the conventional manufacturing method has a problem that a protective tube with high dimensional accuracy such as curvature cannot be produced.

In addition to the above method of bending a straight pipe, as a method of manufacturing a protective tube, a method using press working is conceivable. However, in the case of press working, it is necessary to prepare a mold according to the shape of the protection tube. Therefore, in order to manufacture protective pipes of various shapes using press working, a corresponding number of molds are required, and there is a problem that the manufacturing cost of the molds is enormous. Also, in the design of the mold, there are restrictions on the shape of the protective tube, for example, the curvature of the curved portion cannot be kept below a certain level. In particular, when protecting a thick electric wire such as a high-voltage cable, the protective tube also becomes large, and it is often difficult to bend the protective tube.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a protective pipe that is inexpensive to manufacture and has a high degree of freedom in shape.

(1) A protective pipe according to the present invention is formed in a hollow cylindrical shape to protect another member inserted through the hollow portion, and has a curved portion curved with a predetermined radius of curvature. an outer curved surface forming the outer peripheral side in the radial direction of curvature, an inner curved surface forming the inner peripheral side in the radial direction of curvature, and an intermediate portion between the outer curved portion and the inner curved portion None, and a pair of side curved surfaces arranged to face each other, and each of the pair of side curved surfaces is the outer peripheral side curved portion or the inner peripheral side curved portion at one end side in the curvature radius direction. , the other end side is an open end, and a notch cut from the open end side so that the boundary portion becomes an end point The incision is provided at a position facing each other between the pair of side curved surfaces, and one of the outer peripheral side curved surface and the inner peripheral side curved surface provided so as to continue to the end point , the cuts are bent with the predetermined radius of curvature about an imaginary line connecting the end points of the incisions facing each other between the side curved surfaces.

In this protection pipe, a gutter-shaped member is formed such that a pair of side curved surfaces are bent and connected to an outer curved portion or an inner curved portion at one end side thereof through a boundary portion. Used. In this gutter-shaped member, the cut provided in the side curved surface is provided so as to extend to the vicinity of the outer peripheral side curved surface or the inner peripheral side curved surface. In addition, the above-mentioned gutter-shaped member has a pair of side curved surfaces and an outer periphery formed so as to follow them by curving the outer peripheral side curved surface or the inner peripheral side curved surface around the end point of the cut. The side curved surface or the inner peripheral curved surface is integrally curved. The protective pipe of the present invention is formed by combining such a gutter-shaped member with a member forming the other side of the outer curved surface or the inner curved surface. Therefore, the protective tube of the present invention can be manufactured without forcibly bending a straight tube by bending or press working, etc., as in the prior art. In addition, in the protective tube of the present invention, the curvature, size, etc. of the curved portion can be adjusted freely and with high dimensional accuracy by adjusting the position, number, etc. of the cuts. Therefore, according to the present invention, it is possible to provide a protective pipe that is inexpensive to manufacture and has a high degree of freedom in shape.

(2) The above-mentioned sense of protection is a U-shaped cross section formed by either one of the outer peripheral curved surface and the inner peripheral curved surface and a pair of side curved surfaces. and a lid member that includes the other of the outer curved surface and the inner curved surface, and closes the open ends of the pair of side curved surfaces of the U-shaped member. Preferably.

(3) In the protective tube as described above, each laterally curved surface has at least two said notches, and the open end of each laterally curved surface, between said notches, corresponds to the curvature of said curved portion. It should be arc-shaped. By doing so, the open end of the U-shaped member in contact with the inner curved surface continuously forms a smooth U-shape corresponding to the curvature of the curved portion. As a result, it is possible to easily form a protective pipe whose inner side is smoothly curved.

(4) In the protective pipe described above, the cut is provided as a V-shaped cut, and the V-shaped cut has a boundary with the outer curved surface on each side curved surface. It is cut from the top surface side so as to form a V-shaped vertex, and the vertex of the V-shaped cut facing between the both side curved surfaces is mutually arranged so that both sides of the V-shaped shape are close to each other. The curved portion may be formed by bending the outer peripheral side curved surface around an imaginary line connecting the two and welding both sides of the adjacent V-shaped cut.

According to such a protective pipe, when the V-shaped cut is provided in the side curved surface and the outer peripheral side curved surface is curved so that both sides of the V-shaped cut of the V-shaped cut are close to each other, the side curved surface The curved surfaces can be deformed without overlapping each other, and the cut need only be welded at one location on both adjacent sides. This facilitates welding and facilitates manufacture of the protective tube.

(5) In the protective pipe described above, the V-shaped cuts facing each other between the curved surfaces on both sides may be formed to have the same shape. By doing so, the U-shaped member becomes symmetrical with respect to the extending direction, which facilitates the design of the U-shaped member.

(6) In the protective pipe described above, the inner curved surface may be formed in a plate shape to have a rectangular cross section. By doing so, the inner curved surface arranged to cover the open side of the U-shaped member has a uniform cross section, that is, a plate shape, which facilitates the manufacture of the inner curved surface.

(7) The protective tube may be made of a metal material and arranged with the inner curved surface facing the side of the railroad track. By doing so, even if the paving stones laid around the Tetsu-go orbit are scattered, the metal protection tube reliably protects the internal substances such as the electric wire inserted inside.

(8) A method for manufacturing a protective pipe according to the present invention is a method for manufacturing a protective pipe that is formed in a hollow cylindrical shape and protects another member inserted through the hollow portion, wherein the protective pipe has a predetermined curvature. It has a curved portion curved with a radius, and the curved portion includes an outer peripheral side curved surface forming an outer peripheral side in the curvature radial direction, an inner peripheral side curved surface forming an inner peripheral side in the curvature radial direction, and the outer peripheral side. and a pair of side curved surfaces that form an intermediate portion of the curved portion and the inner curved portion and are arranged to face each other, and one of the outer curved surface and the inner curved surface. and a pair of side curved surfaces, a U-shaped member preparing step of preparing a U-shaped member having a U-shaped cross section; and a connecting step of connecting a lid member having the other side of the U-shaped member so as to close the open end sides of the pair of side curved surfaces in the U-shaped member.

According to this protective pipe manufacturing method, a cut is provided in the side curved surface and extends to the vicinity of the outer curved surface. and curved surfaces on both sides are curved, and the top surface portion is curved according to the curvature of the U-shaped member and connected to the U-shaped portion, thereby easily forming a protective pipe having a curved portion can be manufactured. By doing so, a protective tube having a curved portion can be manufactured at low cost and with high dimensional accuracy.

(9) The U-shaped member preparation step includes a cutting step of providing cuts of substantially the same shape facing each other from both sides of a generally plate-shaped plate-shaped member, and cutting the plate-shaped member so that the cross section has a U-shaped A bending step of bending both sides of the at the end points of the incisions, and a bending step of bending the outer peripheral side curved surface about a virtual line connecting the end points of the incisions facing each other between the both side curved surfaces. step.

According to this protective pipe manufacturing method, the U-shaped member is formed by disassembling it into three steps: a cutting step, a bending step, and a bending step. These cutting step, bending step, and bending step are simple manufacturing steps compared to the step of forming a desired metal part by press working, and the curved portion can be easily formed in the U-shaped member. .

(10) The cutting step includes providing at least two V-shaped cuts as the cuts in each side curved surface of the U-shaped member, and cutting the open end of each side curved surface. between the V-cuts, cutting arcuately corresponding to the curvature of the curved portion.

According to such a protective tube manufacturing method, when a V-shaped cut is provided in the side curved surface and the outer curved surface is curved so that both sides of the V-shaped cut of the V-shaped cut are close to each other. , the side curved surfaces can be deformed without overlapping, and the cut needs to be welded at only one location on both adjacent sides. This facilitates welding and facilitates manufacture of the protective tube.

(11) A protective pipe component according to the present invention is formed in a hollow cylindrical shape, protects another member inserted through the hollow portion, and has a curved portion curved with a predetermined radius of curvature, The curved portion includes an outer curved surface that forms an outer peripheral side in the radial direction of curvature, an inner curved surface that forms an inner peripheral side in the radial direction of curvature, and an intermediate portion between the outer curved portion and the inner curved portion. and a pair of oppositely disposed side curved surfaces, each side curved surface having at least one incision in an opposing position between said side curved surfaces. The incision is cut from the open end of the U-shaped member so that the boundary between the outer peripheral side curved surface and the side curved surface is the end point on each side curved surface, and the cuts are opposed to each other. The curved portion is formed by curving the outer peripheral side curved surface around an imaginary line connecting the vertexes of the cuts.

In this protective tube component, a notch is provided in the side curved surface and extends to the vicinity of the outer curved surface. 3, the U-shaped member including the outer curved surface and the curved surfaces on both sides can be easily bent to manufacture a U-shaped member having a curved portion. By doing so, it is possible to provide a U-shaped member having a curved portion at a low manufacturing cost while securing a high degree of freedom in shape without using a mold for press working.

(12) In the protective tube component described above, the cuts are provided such that V-shaped V-shaped cuts are opposed between the curved surfaces on both sides, and the V-shaped cuts are provided on each side. In the curved surface, the open end is cut so that the boundary with the outer curved surface becomes the vertex of the V shape, and the outer curved surface is curved so that both sides of the V shape are close to each other. The curved portion is formed by welding both sides of the adjacent V-shaped cuts.

According to such a U-shaped member, when the V-shaped cut is provided in the side curved surface and the outer peripheral curved surface is curved so that both sides of the V-shaped cut of the V-shaped cut are close to each other, The side curved surfaces can be deformed without overlapping, and the cut needs to be welded at only one location on both adjacent sides. This facilitates welding and facilitates manufacture of the U-shaped member.

INDUSTRIAL APPLICABILITY The present invention can provide a protective tube that is easy to manufacture and has a high degree of freedom in shape.

1 is a conceptual diagram showing a state in which a protective pipe according to a first embodiment of the present invention is arranged near a railroad track; FIG. 1 is a schematic perspective view showing a protective tube according to a first embodiment of the invention; FIG. FIG. 4 is a plan view showing a plate-like member forming a U-shaped portion of the protective pipe according to the first embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the protective tube which concerns on the 1st Embodiment of this invention, (A) is a schematic side view before bending a U-shaped member, (B) is a FIG. 10 is a schematic side view after FIG. 4 is a conceptual process diagram showing the method for manufacturing the protective pipe according to the first embodiment of the present invention; FIG. 11 is an enlarged side view showing a protective pipe according to a modified example of the invention;

[Embodiment of Protective Tube]

A protective pipe 1 according to an embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 1, the protective tube 1 is provided around a railroad track L and used to protect electric wires such as high-voltage cables for trains. The protective tube 1 is formed in a hollow cylindrical shape and protects a cable inserted through the hollow portion. The protective pipe 1 protects the high-voltage cable, for example, when paving stones K spread in the vicinity of the railroad track L are scattered due to the passage of a train.

As shown in FIG. 2 , the protective tube 1 is formed in a hollow cylindrical shape with a rectangular cross section, and includes a straight tube 10 and a curved tube 20 . The straight tube 10 and the curved tube 20 are connected via a connecting member 30 . The connecting member 30 is composed of conventionally well-known reinforcing hardware and bolts.

The straight tube 10 is formed to have a rectangular cross section from a top surface 11, a bottom surface (not shown) and both side surfaces 13, and extends linearly while maintaining the rectangular shape. The straight tube 10 is composed of a metal tube having a rectangular cross section, and is arranged so that the top surface 11 faces the track side of the railroad track.

Similarly to the straight tube 10, the curved tube 20 is formed to have a rectangular cross section from a top surface 21, a bottom surface 22 and both side surfaces 23, and extends while curving while maintaining the square shape. Thereby, the curved tube 20 forms the curved portion of the protective tube 1 . In addition, the curved tube 20 includes a U-shaped member 24 (see FIG. 5C) having a U-shaped cross section forming a bottom surface 22 and both side surfaces 23, and an inner peripheral curved surface 25 forming a top surface 21. (See FIG. 5(E)).

The U-shaped member 24 extends while curving in a direction intersecting the bottom surface 22 while maintaining the U-shape. The inner peripheral side curved surface 25 is formed in a plate shape and is curved with substantially the same curvature as the curving U-shaped member 24 . The curved tube 20 has an inner curved surface 25 placed on the open ends 23u (see FIG. 3) of both side surfaces 23 of the U-shaped member 24 and coupled by a coupling member 26. FIG. The connecting portion 26 is formed by fixing a connecting hardware 26a welded to the U-shaped member 24 and the inner curved surface 25 with a bolt 26b.

The U-shaped member 24, as shown in FIG. 3, is formed from a substantially rectangular plate-shaped member 24o. The plate-shaped member 24o is configured to be bendable in the same width direction from both side ends. In FIG. 3, the bending line along which the plate member 24o is bent is indicated by a two-dot chain line, and this two-dot chain line is the boundary i between the bottom surface 22 and the side surfaces 23. As shown in FIG. Both sides of the plate-like member 24 o are open ends 23 u of the U-shaped member 24 .

The U-shaped member 24 is provided with a plurality of cuts 27, and the end points of the cuts 27 cut toward the center from both ends of the plate-shaped member 24o are located between the bottom surface 22 and both side surfaces 23. located on boundary i. In this embodiment, the cut 27 is formed as a V-shaped V-shaped cut 27v. The V-shaped cut 27v is a plate-like member that serves as an open end 23u of the U-shaped member 24, with the boundary between the bottom surface 22 and the side surfaces 23 of the U-shaped member 24 (a two-dot chain line in FIG. 3) as an apex 27o. It is cut from both ends in the width direction of 24o.

The V-shaped cuts 27v are formed at opposing positions between the side surfaces 23 of the U-shaped member 24, and the opposing V-shaped cuts 27v are cut to have the same shape. Each side surface 23 is formed with seven V-shaped cuts 27v. In FIG. 3, the V-shaped cuts 27v at both ends in the longitudinal direction are cut at a V-shaped angle of 7.5°, and the other V-shaped cuts 27v are cut at a V-shaped angle of 15°. is included.

Next, the process of bending the U-shaped member 24 on the outer peripheral side curved surface 22 will be described. FIG. 4 shows the state before and after bending the outer peripheral side curved surface 22 of the U-shaped member 24, and (A) shows the state before bending the plate-shaped member 24o into a U-shape by bending the plate member 24o at the boundary i. It is a side schematic diagram, and (B) is a side schematic diagram after bending an outer peripheral side curved surface.

After bending both sides of the plate-like member 24o at the boundary i, the U-shaped member 24 is formed with the imaginary line j connecting the apexes 27o of the V-shaped cuts 27v facing each other between the curved surfaces 23 on both sides ( 3), and the outer curved surface 22 can be curved (see FIG. 4A).

After the outer curved surface 22 is curved, both adjacent sides 27i of the V-shaped notch 27v are welded to form a welded portion 27c, thereby fixing the U-shaped member 24 in a curved state. (See FIG. 4B). That is, the U-shaped member 24 is formed by curving the bottom surface 22 so that both sides 27i of the V-shaped cut 27v are close to each other.

According to the protective pipe 1, when the V-shaped cut 27v is provided in the side curved surface 23 and the outer curved surface 22 is curved so that both sides 27i of the V-shaped cut 27v are close to each other, The outer curved surface 22 can be curved without the side curved surfaces 22 overlapping each other, and the welded portion 27c needs to be only one on both adjacent sides. This facilitates welding and facilitates manufacture of the protective tube 1 .

Between the V-shaped cuts 27v, both ends of the plate-shaped member 24o in the width direction, which are the open ends 23u of the U-shaped member 24, are formed in an arc shape to match the curvature of the curved portion. As a result, when the U-shaped member 24 is formed from the plate-shaped member 24o, the open end 23u of the U-shaped member 24 is formed in a continuous and smooth U-shape with substantially the same curvature as the curvature of the curved portion. (See FIG. 4(B)).

The bending tube 20 is a U-shaped member curved so as to cover the open side of the U-shaped member 24 by bending a plate-shaped inner peripheral side curved surface 25 formed to have substantially the same width as the facing portion. 24 , and the connecting member 26 connects the contacting portion between the open end 23 u of the U-shaped member 24 and the inner curved surface 25 .

[Method for manufacturing protective tube]

Next, a method for manufacturing the curved tube 20 of the protective tube 1 according to this embodiment will be described with reference to FIG. FIG. 5 is a conceptual process diagram showing the order of manufacturing the bending tube 20. As shown in FIG.

The manufacturing method of the protective tube 1 includes steps of preparing a U-shaped member 24 that is a component of the curved tube 20 (S1 to S4), and forming the U-shaped member 24 and the inner curved surface 25. Inner peripheral side curved surface bonding steps (T1 to T3) for bonding. 5A to 5D show the U-shaped member preparation process, and FIGS. 5E to 5G show the inner curved surface bonding process.

The U-shaped member preparing process includes a plate-like member preparing step (S-1) of preparing a substantially rectangular plate-like member 24o, and a cutting step of providing cuts 27 having substantially the same shape facing each other from both sides of the plate-like member 24o. (S-2), a bending step (S-3) of bending both sides of the plate member 24o so that the cross section has a U-shape, and a bending step (S-4) of bending the bottom surface 22. including.

In the plate-like member preparing step (see FIG. 5A), a substantially rectangular plate-like member 24o is prepared (S-1). The plate member 24o is mainly made of iron and is plated with zinc on both front and back surfaces. The length dimension, width dimension, and thickness dimension of the plate-like member 24o are appropriately selected according to the use of the protection pipe 1 and the installation location.

In the cutting step (see FIG. 5B), a V-shaped cut 27v is formed by cutting the plate member 24o (S-2). In addition, in the cutting step, in addition to the V-shaped cuts 27v, the plate-shaped member 24o is cut so that both sides of the plate-shaped member 24o that becomes the U-shaped open end 23u form an arc between the V-shaped cuts 27v. 24o is cut (see FIG. 3). Thus, in the cutting step, the plate member 24o can be cut into a desired shape.

In the bending step (see FIG. 5(C)), both sides of the plate-like member 24o are formed into a bottom surface 22 and both side surfaces 23 by bending the vertex 27o of the V-shaped cut 27v at the boundary i. A U-shaped member 24 is formed (S-2). The cutting step and bending step are performed by conventionally well-known sheet metal processing.

In the curving step (see FIG. 5(D)), the bottom surface 22 is curved so that both sides of the V-shaped notch 27v are close to each other (S-4). At this time, the bottom surface 22 portion is centered on a virtual line j (see FIG. 3) connecting the V-shaped apexes 27o of the V-shaped cuts 27v facing each other on both side surfaces 23, that is, the end points of the cuts 27 in the width direction. curved into.

The angle at which the bottom surface 22 is curved is the angle of the V-shaped notch 27v of each side surface 23 portion. The curved U-shaped member 24 is fixed by welding adjacent sides 27i of the V-shape (see FIG. 4B) to form welded portions 27c. Further, the open end 23u of the U-shaped member is formed in an arc shape, and the U-shaped member 24 is formed in a continuous arc shape in a curved state.

Through the above steps, in the U-shaped member preparation step, the U-shaped member 24 is formed so that the cross section is U-shaped from the bottom surface 22 and the side surfaces 23 connected to both pieces of the bottom surface 22 . , the U-shaped member 24 extends while maintaining the U-shape, and is formed to have a curved portion that curves in a direction intersecting the bottom surface 22 while extending.

In the method of manufacturing the curved portion 20 according to the present embodiment, each side surface 23 of the U-shaped member 24 is provided with at least one notch 27 facing between the side surfaces 23 . The notch 27 is cut from the open end 23u of the U-shaped member 24 so that the boundary i between the bottom surface 22 and the side surface 23 becomes the end point of the notch 27 on each side surface 23 . Further, the bottom surface 22 is curved around an imaginary line j connecting the apexes 27o of the opposing cuts 27, and the sides of the cuts 27 are welded to form a curved portion.

In the present embodiment, the U-shaped member 24 is a generally rectangular plate-shaped member 24o that is made of a metal material and has one side surface 23 and the other side surface 23 that can be bent with the same size in the width direction. The plate-shaped member 24o has a plurality of V-shaped cuts 27v that are cut in a V-shape from the outside to the inside at predetermined intervals in the longitudinal direction of the one and the other side surfaces 23. The V-shaped cuts 27v face each other in the same shape with the vertices 27o facing each other (see FIG. 3).

Here, when the V-shaped cut 27v is provided in the side curved surface 23 and the outer curved surface 22 is curved so that both sides 27i of the V-shaped cut 27v are close to each other, the side curved surface The outer curved surface 22 can be curved without overlapping the 22, and the welded portion 27c needs to be only one on both adjacent sides. This facilitates welding and facilitates manufacture of the U-shaped member.

The inner curved surface bonding step includes an inner curved surface preparation step (T-1) for preparing an inner curved surface 25 for covering the open side of the U-shaped member 24, and an inner curved surface preparation step (T-1). It includes an inner curved surface curving step (T-2) for curving the surface 25 and a coupling step (T-3) for arranging and coupling the curved inner peripheral curved surface 25 to the U-shaped member 24 .
including.

In the inner curved surface preparation step (see FIG. 5(E)), the plate-shaped inner curved surface 25 is prepared (T-1). As with the U-shaped member 24, both the front and back sides of the inner curved surface 25 are galvanized. The length, width, and thickness of the inner curved surface 25 correspond to the U-shaped member 24 so that the U-shaped member 24 can be covered and the wires can be protected from scattering of paving stones. selected.

In the inner peripheral curved surface curving step (see FIG. 5F), the plate-like inner peripheral curved surface 25 is curved to a curvature corresponding to the curved U-shaped member (T-2). The inner curved surface 25 is also curved by conventionally well-known sheet metal processing.

In the joining step (see FIG. 5(G)), the curved inner peripheral curved surface 25 is placed on the U-shaped member 24 and joined by the joining member 26 (T-3). Specifically, the curved inner peripheral side curved surface 25 is placed on the curved U-shaped member 24 and coupled with the open end 23u of the U-shaped member 24 in contact with the curved tube 20. is manufactured. The curved tube 20 is formed to have a rectangular cross section by a U-shaped member 24 and a plate-shaped inner peripheral side curved surface 25 . Note that the connecting member 26 (see FIG. 2) is omitted in FIG. 5(G).

[Modification]

A protective pipe 1 according to a modified example of the present invention will be described with reference to FIG. . FIG. 4 shows the state before and after bending the outer peripheral side curved surface 22A of the U-shaped member 24A according to the modification, and (A) shows a U-shaped U-shaped member formed by bending the plate-shaped member 24o at the boundary i. 24A is a schematic side view before bending the U-shaped member 24A, and (B) is a schematic side view after bending the outer peripheral side curved surface 22A of the U-shaped member 24A.

The U-shaped member 24A differs from the U-shaped member 24 in the shape of the notch 27, and has the same configuration as the U-shaped member 24 in other parts. That is, the U-shaped member 24A has a linear cut 27l instead of a V-shaped cut.

After bending both sides of the plate-like member 24o at the boundaries i, the U-shaped member 24A is formed with the imaginary line j connecting the end points 27o of the opposed cuts 27l between the curved surfaces 23 on both sides (see FIG. 3). ), and the outer curved surface 22 can be curved (see FIG. 6A).

When the outer curved surface 22 is curved, one side 27i of the linear cut 27l shifts to the front side of the side surface 23, and the other side 27i shifts to the back side of the side surface 23, so that the side surface 23 forms a substantially triangular overlapping portion. do. The vicinity of the side 27i of the overlapping side surface 23 is welded to form welded portions 27c on both the front and back sides of the side surface (see FIG. 6B). Thereby, the U-shaped member 24A is fixed in a curved state.

According to the U-shaped portion 24A, a linear cut 27l is provided in the side curved surface 23, and both sides 27i of the cut 27l are shifted to the front side of the side surface 23, and the other side 27i is shifted to the back side of the side surface 23. That is, the welded portions 27c are provided at two locations. However, only one side may be welded.

The plate-like member 24o has both ends in the width direction, which are the open ends 23u of the U-shaped member 24A, between the linear cuts 27l and are formed in an arc shape to match the curvature of the curved portion. As a result, when the U-shaped member 24A is formed from the plate-shaped member 24o, the open end 23u of the U-shaped member 24 is formed into a continuous and smooth U-shape with substantially the same curvature as the curvature of the curved portion. (See FIG. 6(B)).

In this embodiment, the protective pipe has been described as being arranged around the railroad track. In this case, even if the paving stones spread around the railroad track are scattered by the passage of the train, the protective pipe is made of a metal material, so that the wires inside can be reliably protected. . However, the protection pipe may be arranged in other places than the circumference of the railroad tracks. Furthermore, the protective pipe has a top surface portion that is susceptible to scattering of stones by a single inner peripheral curved surface, and a welded portion is provided on the side curved surface. As a result, the protective tube can more reliably protect the electric wire.

In the present embodiment, the description has been given of the form in which the protective pipe is formed to have a substantially square-shaped cross section. However, the protection pipe may be of other shapes as long as it extends in a curved manner and the electric wire can be passed through it. For example, the inner curved surface may be formed to have an arcuate cross-section so that the cross-section of the protective tube is dome-shaped.

In this embodiment, by using the U-shaped member as a component of the protective pipe, the protective pipe can be stably arranged during construction even at an unstable construction site. However, as a part of the protective tube, a part having a cross-sectional shape other than the U-shaped member may be used.

In this embodiment, the inner curved surface on the inner side of the curved portion of the protective tube is connected to the U-shaped member on the outer side using a connecting member. As a result, the inner curved surface can be removed, and a plurality of electric wires can be orderly arranged inside the U-shaped member, which facilitates construction and inspection.

In the present embodiment, the open end 23u of the U-shaped member 24 between the cuts 27 is formed in an arc shape to match the curvature of the curved portion. However, the open end 23u may be straight rather than arcuate. In that case, since the open end 23u of the U-shaped member 24 forms a corner, the inner peripheral curved surface 25 may be curved to accommodate the corner.

In this embodiment, the form in which the side curved surface 23 has a plurality of cuts has been described. However, the cuts may be one on each side as long as they are opposed between the sides. The number of cuts can be appropriately changed according to the shape of the U-shaped member. Moreover, when the cut is a V-shaped cut, the angle of the V-shaped cut 27v and the number of the V-shaped cuts 27v can be appropriately changed according to the curvature rate.

In this embodiment, the protective tube 1 is divided into the straight tube 10 and the curved tube 20, and the curved tube 20 forms the curved portion. However, the protective tube 1 only needs to have curved portions, and may be formed by one tube having both straight regions and curved portions.

The protective tube according to the present invention can be used to protect electric wires and the like.

1 protective tube 10 straight tube 20 curved tube (curved portion)
21 Top surface 22 Bottom surface 23 Side surface 23c Open end 24 U-shaped member 24o Plate-shaped member 25 Inner peripheral side curved surface 26 Coupling member 27 Cut 27l Linear cut 27v V-shaped cut 30 Connecting member L Railroad track K Paving stone

Claims (9)

A protective tube that is formed in a hollow cylindrical shape and protects another member that is inserted through the hollow portion,
Having a curved portion curved with a predetermined radius of curvature,
The curved portion is
an outer peripheral side curved surface forming an outer peripheral side in the curvature radius direction;
an inner peripheral curved surface forming an inner peripheral side in the curvature radial direction;
a pair of side curved surfaces forming an intermediate portion between the outer curved surface and the inner curved surface and arranged to face each other;
The pair of side curved surfaces are formed on one end side in the curvature radial direction so as to be continuous with the outer peripheral curved surface or the inner peripheral curved surface through a boundary portion, and the other end is curved. has an open end and a notch that is cut from the open end side so that the boundary portion becomes an end point,
The notch is provided at a position facing each other between the pair of side curved surfaces,
Either the outer curved surface or the inner curved surface, which is provided so as to follow the end point, forms an imaginary line connecting the end points of the cuts facing each other between the side curved surfaces. It is bent so as to be curved with the predetermined radius of curvature as an axis,
a U-shaped member having a U-shaped cross section formed by one of the outer curved surface and the inner curved surface and a pair of side curved surfaces;
A protective tube comprising the other of the outer curved surface and the inner curved surface, and a cover member that closes the open end side of the pair of side curved surfaces in the U-shaped member. A protective tube that is formed in a hollow cylindrical shape and protects another member that is inserted through the hollow portion,
Having a curved portion curved with a predetermined radius of curvature,
The curved portion is
an outer peripheral side curved surface forming an outer peripheral side in the curvature radius direction;
an inner peripheral curved surface forming an inner peripheral side in the curvature radial direction;
a pair of side curved surfaces forming an intermediate portion between the outer curved surface and the inner curved surface and arranged to face each other;
The pair of side curved surfaces are formed on one end side in the curvature radial direction so as to be continuous with the outer peripheral curved surface or the inner peripheral curved surface through a boundary portion, and the other end is curved. has an open end and a notch that is cut from the open end side so that the boundary portion becomes an end point,
The notch is provided at a position facing each other between the pair of side curved surfaces,
Either the outer curved surface or the inner curved surface, which is provided so as to follow the end point, forms an imaginary line connecting the end points of the cuts facing each other between the side curved surfaces. It is bent so as to be curved with the predetermined radius of curvature as an axis,
each side curved surface having at least two said cuts;
The protective tube, wherein the open end of each side curved surface is formed in an arc shape corresponding to the curvature of the curved portion between the cuts. The cut is provided as a V-shaped V-shaped cut,
The V-shaped cut is cut from the inner peripheral side curved surface side so that the boundary with the outer peripheral side curved surface becomes the apex of the V shape on each side curved surface,
The outer peripheral side curved surface is curved around a virtual line connecting the vertices of the V-shaped cuts facing each other between the two side curved surfaces so that both sides of the V shape are close to each other. 3. The protective pipe according to claim 1 or 2 , wherein said curved portion is formed by welding both sides of said V-shaped cut. 4. The protective tube according to claim 3 , wherein said V-shaped cuts facing each other between said side curved surfaces are provided to have the same shape. The protective pipe according to any one of claims 1 to 4 , wherein the inner peripheral curved surface is formed in a plate shape to have a rectangular cross section. The protective pipe according to any one of claims 1 to 5 , which is made of a metal material and arranged with the inner curved surface facing the side of the railroad track. A method for manufacturing a protective tube that is formed in a hollow cylindrical shape and that protects another member that is inserted through the hollow portion,
The protective tube has a curved portion curved with a predetermined radius of curvature, and the curved portion has an outer peripheral side curved surface forming the outer peripheral side in the direction of the radius of curvature and an inner periphery forming the inner side in the direction of the radius of curvature. It has a side curved surface and a pair of side curved surfaces that form an intermediate portion between the outer peripheral curved surface and the inner peripheral curved surface and are arranged to face each other,
A U-shaped member having a U-shaped cross section formed by one of the outer curved surface and the inner curved surface and a pair of side curved surfaces. a preparation process;
a connecting step of connecting a lid member having the other of the outer curved surface and the inner curved surface so as to close the open end side of the pair of side curved surfaces in the U-shaped member. ,
The U-shaped member preparation step includes:
A cutting step of providing opposing cuts having substantially the same shape from both sides of a substantially plate-like plate-like member;
a bending step of bending both sides of the plate-like member at the end points of the cuts so that the cross section has a U-shape;
A method of manufacturing a protective tube, comprising: curving the outer curved surface around an imaginary line connecting the end points of the cuts facing each other between the curved surfaces on both sides. The cutting step includes providing at least two V-shaped V-shaped cuts as the cuts on each side curved surface of the U-shaped member;
8. The method of claim 7 , comprising cutting the open end of each side curve in an arc corresponding to the curvature of the curve between the V-cuts. It is formed in a hollow cylindrical shape and protects other members inserted through the hollow part,
It has a curved portion curved with a predetermined radius of curvature, and the curved portion includes an outer curved surface forming the outer peripheral side in the direction of the radius of curvature, and an inner curved surface forming the inner peripheral side in the direction of the radius of curvature; A part of a protective tube having a pair of side curved surfaces forming an intermediate portion of the outer curved surface and the inner curved surface and arranged to face each other,
a U-shaped member having a U-shaped cross section formed by one of the outer curved surface and the inner curved surface and a pair of side curved surfaces;
a lid member that includes the other of the outer curved surface and the inner curved surface and closes the open end side of the pair of side curved surfaces in the U-shaped member,
each side curved surface is provided with at least one incision at opposing positions between said side curved surfaces;
The incision is cut from the open end of the U-shaped member so that the end point of each side curved surface is the boundary between the outer peripheral side curved surface and the side curved surface,
The curved portion is formed by curving the outer peripheral side curved surface around a virtual line connecting the apexes of the opposing cuts,
The cut is provided so that the V-shaped V-shaped cut is opposed between the curved surfaces on both sides,
The V-shaped cut is cut from the open end so that the boundary with the outer curved surface becomes the vertex of the V-shaped shape on each side curved surface,
A part of a protective pipe, wherein the outer peripheral curved surface is curved so that both sides of the V-shape are close to each other, and the curved portion is formed by welding both sides of the V-shaped incision that are close to each other. .

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