JP3066687U - Tube fixing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe mouth which can securely fix an inner pipe, is relatively inexpensive, is easy to assemble, and has sufficient vibration resistance without changing the structure itself for each outer pipe shape. It is to provide a fixing structure. SOLUTION: The pipe opening fixing structure according to the present invention has a structure in which a plurality of inner pipes inserted into an outer pipe connecting between vertical holes provided apart from each other are fixed at an open end of the outer pipe. There, a spacer is interposed in a gap between adjacent inner pipes dispersedly arranged on a base bar attached to the opening end of the outer pipe or a vertical hole peripheral wall in the vicinity thereof, and a plurality of inner pipes are integrated,
The inner tube group is bundled by tightening the wire wound around the outer periphery of the integrated inner tube group, and the wire is held at the open end of the outer tube or in the vicinity thereof via the base bar.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a structure in which a plurality of inner pipes inserted into an outer pipe connecting between vertical holes provided apart from each other are fixed at an open end of the outer pipe.

[0002]

[Prior art]

 In order to perform so-called optical communication using an electromagnetic fiber as a carrier wave and an optical fiber as a transmission path, it is necessary to install an optical communication cable such as an optical fiber, and the installation is performed by various methods. For example, a method of inserting an optical communication cable into a pipe buried underground is well known. That is, as shown in FIG. 1, a vertical hole 101 is dug at a predetermined distance, the vertical holes 101 are connected to each other by a large-diameter outer tube 102, and a plurality of smaller-diameter inner tubes 103 are arranged in the outer tube 102. Generally, an optical communication cable is passed through each of the 103s.

[0003] At this time, the optical communication cable is exposed from the inner tube 103 and fixed to the wall surface of the vertical hole 101 in the vertical hole 101, but the inner tube 103 expands and contracts in the vertical hole 101 as described below. There is a problem that the joints between the cables are hindered.

That is, since the inner tube is formed of a resin, for example, polyvinyl chloride or polyethylene, and the resin easily expands or contracts due to a change in temperature, when both ends of the inner tube are fixed at both open ends of the outer tube. In addition, the axial length of the inner tube tends to change.

[0005] For example, the axial elongation amount [Delta] L of the inner tube in each case using a polyvinyl chloride or polyethylene inner tube, [Delta] L 'is, 6.0 × 10 ^-5 ° C. The coefficient of linear expansion of 1 polyvinylchloride alpha ^{- 1.} Assuming that the temperature change Δt is 30 ° C., the unit length L of the tube is 250 m, and ΔL = L × Δt × α = 450 mm by the following equation: 2 The linear expansion coefficient α ′ of polyethylene is 12 × 10 ⁻⁵ ° C. ⁻¹ , Assuming that the temperature change Δt is 30 ° C. and the unit length L of the tube is 250 m, an extremely large value is obtained as follows:

Therefore, when the temperature changes by 30 ° C., the inner pipe projects into the vertical hole by about 450 mm when using polyvinyl chloride and about 900 mm when using polyethylene, and as a result, the joint of the cable is disturbed. That is.

Therefore, in order to avoid the above-mentioned inconvenience due to the protrusion or retraction of the inner tube with respect to the outer tube as described above, one of the two open ends of the outer tube is directly fixed to the outer tube, At the other open end, a tube mouth fixing structure is adopted in which the inner tube is indirectly fixed via a sleeve fixed to the outer tube.

[0008] In this tube fixing structure, as shown in FIG. 2, an anchor 105 is cast on a wall surface 104 of the outer tube 102, and a packing 106 and a fixing plate 107 are attached to the anchor 105, as shown in FIG. The inner tube 103 is directly fixed by the fixing bar 108, the band 109, the flat washer 110, and the hex nut 111. On the other hand, on the free side, as shown in FIG. 3, in addition to the above-described configuration, a duct sleeve 112 is used, and the inner pipe 103 is indirectly fixed to the outer pipe 102 via the duct sleeve 112. is there. The duct sleeve 112 used on the free side is capable of absorbing expansion and contraction of the inner tube 103.

[0009]

[Problems to be solved by the invention]

 However, as described above, the conventional pipe opening fixing structure shown in FIGS. 2 and 3 includes an anchor 105, a packing 106, a fixing plate 107, a band fixing bar 108, a band 109, a flat washer 110, a hexagon nut 111, and a duct. Since the sleeve 112 is used, various components must be used, and the assembling thereof is complicated and costly.

In addition, since the packing 106 is made of metal and the duct sleeve 112 is made of resin, and the two have different linear expansion coefficients, other metal parts are required for expansion and contraction of the tube made of resin in the radial direction. It cannot be easily handled. In addition, there is a disadvantage that the tube fixing structure itself must be different for each outer tube form.

[0011] Furthermore, since the pipe opening fixing structure for performing optical communication is installed underground in a place where traffic is relatively heavy, such as a national road, vibration caused by a vehicle for a long period of time is sufficient. It must be able to withstand.

The purpose of the present invention is to ensure that the inner tube is securely fixed to the outer tube, to be relatively inexpensive and easy to assemble, and to have sufficient vibration resistance without making the structure itself different for each form of the outer tube. An object of the present invention is to provide a tube port fixing structure having a characteristic.

[0013]

[Means for Solving the Problems]

 This invention has a structure in which a plurality of inner pipes inserted into an outer pipe connecting between vertical holes provided apart from each other are fixed at an open end of the outer pipe, A plurality of inner pipes are integrated by interposing a spacer in the gap between adjacent inner pipes distributed on a base bar attached to the peripheral wall of the vertical hole in the vicinity, and the inner pipes are integrated. The inner tube group is bundled by tightening the wound wire, and the wire is fixed to the open end of the outer tube or in the vicinity thereof via a base bar.

Further, in the embodiment, the base bar has a hook to which one end of the wire is fastened, the base bar has an eyebolt to which the other end of the wire is fastened, and the base bar is located outside the inner tube group. In addition, it is advantageous to provide a stopper for preventing the spacer that is not in contact with the wire from collapsing, that the spacer is made of rubber, and that the inner tube group has a multi-stage arrangement corresponding to the shape of the outer tube.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically with reference to the drawings. The difference between the fixed side where the inner tube is directly fixed to the outer tube and the free side where the inner tube is fixed to the outer tube via the sleeve is that the object to be fixed is the inner tube (fixed side). Or the sleeve (free side), in other words, only the diameter of the object to be fixed is different. Therefore, the following description will be made without distinguishing between the fixed side and the free side.

FIG. 4 is an end view showing a case where the outer tube is a round tube, that is, a tube opening fixing structure for a round tube. The pipe opening fixing structure includes a base bar 12 attached to a wall surface of a vertical hole at a lower end of an opening of the round pipe 11, and a plurality of inner pipes 13 arranged in parallel and stacked on the base bar 12 and dispersed in the round pipe 11. , A plurality of inner tubes 13, which are composed of spacers 14 of various shapes arranged in gaps between adjacent inner tubes 13, and wires 15 wound around the outer periphery of the inner tube group. A plurality of inner tubes 13 are integrated with a spacer 14 interposed between adjacent adjacent spaces, and the inner tube group is bundled by tightening a wire 15 wound around the outer periphery of the integrated inner tube group. 15 is fixed to the open end of the round tube 11 or in the vicinity thereof.

At this time, the base bar 12 includes a hook 16 to which one end of the wire 15 is fastened and an eye bolt 17 to which the other end of the wire 15 is fastened, and the length of the eye bolt 17 can be adjusted with respect to the base bar 12. This is advantageous because a strong tightening force can be obtained.

When the base bar 12 is provided with a stopper 18 that is located outside the inner tube group and prevents the spacer 14 that is not in contact with the wire 15 from collapsing, the inner tube group can be more firmly integrated. Can be advantageous.

In the above-described embodiment, by interposing the spacer 14 in the gap between the inner tubes 13, vibration from the ground surface can be dispersed and absorbed by the spacer 14, but the spacer 14 is made of rubber. By doing so, a structure having excellent vibration resistance can be given as a whole fixing structure, which is more preferable.

According to this configuration, the inner tube 13 is securely fixed at the open end of the round tube 11. This structure can be achieved by a relatively inexpensive and easy assembling structure, and has excellent vibration resistance because the spacer 14 is used.

The wire 15 is preferably made of a corrosion-resistant metal material, for example, SUS304.

The case where the outer tube is the round tube 11 has been described above. Even when the outer tube is not the round tube 11, a multi-stage arrangement of the inner tube group corresponding to the form of the outer tube is realized. Can be. Hereinafter, a case where the outer tube is the side groove 19 will be described as an example.

FIG. 5 is an end view showing a case where the outer tube is a side groove, that is, a tube opening fixing structure for the side groove. This pipe opening fixing structure is such that the inner pipes 21 are arranged in parallel and stacked in a distributed manner according to the shape of the side groove 19, and the basic configuration is the same as the pipe opening fixing structure for a round pipe. This is one in which the inner tube group is integrated by using spacers 22 and stoppers 26 having different shapes.

Therefore, although the mouth opening fixing structure for the round pipe and the side groove has been exemplified, as described above, the mouth opening fixing structure according to the present invention can be formed in any form only by changing the spacer 22 and the stopper 26. It can also be applied to tubes.

Incidentally, the above-described fixing structure can be assembled according to the following procedure. The fixing structure for a round tube will be described with reference to FIG. First, a base bar 12 having a hook 16 and a stopper 18 fixed thereto is prepared. The base bar 12 is attached to the wall surface of the vertical hole on the side of the round tube 11, and one end of the wire 15 is hooked on the hook 16. Next, the spacers 14 are arranged in parallel on the base bar 12, the inner tubes 13a, 13b, 13c are arranged on the upper side thereof, and the inner tubes 13 and the spacers 14 are alternately laminated as shown in FIG. . At this time, an assembling aid (not shown) is attached to the spacers 14 located on the outer periphery of the inner tubes 13a and 13d, and the spacers 14 located on the outer periphery of the inner tubes 13c and 13g are applied to the stopper 18. Make contact. Finally, the inner tube group integrated by interposing the spacer 14 as described above is wound around the wire 15, pulled until the wire 15 comes into contact with the spacer 14, and maintained in this state, and a wire clip (shown in FIG. The other end of the wire 15 is connected to the eyebolt 17 via a screw, etc., and the nut of the eyebolt 17 is tightened and fixed to the base bar 12 to give a tightening torque.

When the wire 15 is wound at the time of assembling, it is the reason that the wire 15 is wound with an assembling aid (not shown) attached to the spacer 14 located on the outer periphery of the inner pipe a and the inner pipe d. This is because the spacer 14 can be prevented from collapsing, and the working efficiency is improved.

[0027]

【Example】

 Next, the degree of fixing force of the above-mentioned tube fixing structure was examined by an experiment. Prior to the experiment, a tube opening fixing structure for a round tube shown in FIG. 4 was assembled. The diameter of the round tube 11 was 300 mm, the diameter of the inner tube 13 was 50 mm, the material of the tube was polyvinyl chloride, and the spacer was rubber.

In Experiment 1, a pipe mouth fixing structure for a round pipe was manufactured by applying two types of tightening torques in the light of an actual machine, and tension was applied to each of the inner pipes 13a to 13l. , The maximum fixing force between when the surface of the inner tube 13 and the spacer 14 slipped was measured. By the structure shown in FIG. 4, among the plurality of inner tubes 13, those having the same contact area with the spacer 14 are grouped into the same group, that is, the inner tubes (a, c, d, g, k, l) are group A, the remaining inner tubes (b, h, j) on the outer circumference of the inner tube group are group B, and the inner tubes (e, f, i) located at the center of the inner tube group. ) Is group C, and when the above two types of tightening torques (20 kgf · cm or 50 kgf · cm) were applied, the average value of the maximum fixing force (kgf) in each group was determined.

[0029]

[Table 1] According to the experimental results, even in the group C having a relatively low maximum fixing force, the necessary and sufficient maximum fixing force was obtained after the actual construction. In addition, when the tightening torque was set to 50 kgf · cm, the maximum fixing force in each group showed a higher value than when the tightening torque was set to 20 kgf · cm. However, when the tightening torque is set to 50 kgf · cm, there is a possibility that distortion may occur in various parts of the inner tube 13. Therefore, it is preferable that the tightening torque is set to about 20 to 30 kgf · cm.

Further, in Experiment 2, a pipe port fixing structure for a gutter was prepared by applying two types of tightening torques in the light of the actual machine, and tension was applied to each of the inner pipes 21a 'to 21l'. The maximum fixing force from when the tension was started to when the surface of the inner tube 21 and the spacer 22 slipped was measured. Note that the pipe groove fixing structure itself for the gutter is unique as compared with that for the round pipe, and the tightening torque is not evenly applied to each inner pipe 21 depending on the structure and the winding method of the wire 23. Of the inner tubes 21 having a relatively small tightening force due to the winding of the wire 23, the group A is a group D and the tightening force due to the winding of the wire 23. The relatively large inner pipes (e ', f', g ', h', i ', k', l ') are group E, and the above two types of tightening torque (20 kgf.cm or 50 kgf.cm) The average value of the above maximum fixing force (kgf) in each group was calculated in the case of applying. The diameter of the wire 23 was 6 mm.

[0031]

[Table 2] According to the experimental results, when the tightening torque was set to 20 kgf · cm, sufficient maximum fixing force was not obtained during construction. When the tightening torque was 50 kgf · cm, the maximum fixing force of both groups showed a sufficiently high value. This tendency was more evident than that of the fixed structure for round tubes. As a result, it is desirable that the tightening torque be approximately 50 to 60 kgf · cm.

As described above, in Experiments 1 and 2, polyvinyl chloride was used as the pipe material. However, it is needless to say that similar results can be obtained by using polyethylene. Also, it was found that it is preferable to wind and tighten the wire in a state where the tube fixing structure is almost circular.

The above description is merely an example of the embodiment of the present invention, and various changes can be made within the scope of the claims.

[0034]

[Effect of the invention]

 According to this invention, the inner tube can be fixed securely, relatively inexpensive and easy to assemble, and a tube opening fixing structure having sufficient vibration resistance without changing the structure itself for each outer tube shape. Provided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a relationship between a vertical hole, an outer pipe, and an inner pipe when the inner pipe is buried in the ground.

FIG. 2 is an exploded view showing a fixed side of a conventional mouthpiece fixing structure.

FIG. 3 is an exploded view showing a free side of a conventional pipe fixing structure.

FIG. 4 is an end view showing a tube port fixing structure for a round tube according to the present invention.

FIG. 5 is an end view showing a pipe groove fixing structure for a gutter according to the present invention.

DESCRIPTION OF SYMBOLS 11 Round tube 12 Base bar 13 Inner tube 14 Spacer 15 Wire 16 Hook 17 Eye bolt 18 Stopper 19 Side groove 20 Base bar 21 Inner tube 22 Spacer 23 Wire 24 Hook 25 Eye bolt 26 Stopper 101 Vertical hole 102 Outer tube 103 Inner tube 104 Wall surface 105 Anchor 106 Packing 107 Fixing plate 108 Band fixing bar 109 Band 110 Flat washer 111 Hex nut 112 Duct sleeve a, c, d, g, k, l Inner tube (A group) B, h, j Inner tubes (group B) other than the inner tubes located on the outer periphery of the inner tube group (group B) e, f, i Inner tubes (group C) located at the center of the inner tube group a ', b' , C ', d', j 'inner tube (D group) located at the part where the force due to the winding is weak e', f ', g', h ', i', k ', l' winding Tube located in the area where the force is strong (E group)

Claims (6)

[Utility model registration claims] 1. A structure in which a plurality of inner pipes inserted into an outer pipe connecting between vertical holes provided apart from each other are fixed at an open end of the outer pipe. Alternatively, a spacer is interposed in a gap between adjacent phases of a plurality of inner pipes dispersedly arranged on a base bar attached to a peripheral wall of a vertical hole in the vicinity thereof, and a plurality of inner pipes are integrated, and an outer periphery of the integrated inner pipe group is formed. A pipe mouth fixing structure in which a group of inner pipes is bundled by tightening a wound wire, and the wire is fixed to an open end of the outer pipe or in the vicinity thereof through a base bar. 2. The tube opening fixing structure according to claim 1, wherein the base bar includes a hook to which one end of the wire is fastened. 3. The tube opening fixing structure according to claim 1, wherein the base bar includes an eyebolt to which the other end of the wire is fastened. 4. The method according to claim 1, wherein
The mouth opening fixing structure, wherein the base bar includes a stopper that is located outside the inner tube group and that prevents the spacer that is not in contact with the wire from collapsing. 5. The method according to claim 1, wherein:
A tube opening fixing structure, wherein the spacer is made of rubber. 6. The method according to claim 1, wherein
A tube opening fixing structure, wherein the inner tube group is formed in a multi-stage arrangement corresponding to the shape of the outer tube.