JP2001303514A - Cable covering tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cable covering tool effectively exerting a vibration control effect even against a large-amplitude vibration phenomenon in particular and economical in workability and machining cost. SOLUTION: This cable cover tool 1 is a nearly cylindrical member made of rubber, i.e., a flexible raw material, and it is provided with continuous lugs 2 in the longitudinal direction on the outer surface and a slit 3 in the longitudinal direction. The cable cover tool 1 is inserted to an installed cable body 4 by expanding the slit 3 as shown by Fig. 1 (a) and (b) and the portion of the slit 3 is connected by heating and depositing or the like. Since the cable cover tool is made of rubber, it can be locally deformed to follow aerodynamic force due to its flexibility, and it can exert an effective vibration control action against large-amplitude vibrations.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable jacket used by attaching to an outer peripheral surface of a cable stayed bridge cable or a general construction cable.

[0002]

2. Description of the Related Art In a construction cable used for a cable-stayed bridge or the like, a cable strand is covered with a resin material such as polyethylene in order to prevent corrosion of the cable strand.
It is known that since the construction cable has a smooth cylindrical surface, unstable phenomena such as vortex excitation, wake galloping, and rain vibration are caused by wind or rain.

As shown in FIG. 9 (a), a vortex excitation generates a periodic Karman vortex 82 formed on the leeward side of an overhead cable 81.
Is the self-excited vibration generated when the emission frequency of the overhead wire and the natural frequency of the overhead cable 81 match.

As shown in FIG. 9 (b), wake galloping is performed by using an overhead side overhead cable 8 arranged in series.
3 and the wake 84 of the wake,
5 is a phenomenon that causes severe vibration.

[0005] In the rain vibration, as shown in FIG. 9 (c), when rainfall is accompanied, two water passages 87, 88 are formed in the overhead cable 86, and the rain water causes water on the surface of the overhead cable 86 by the water channel. This is a phenomenon in which the separation point becomes asymmetrical, and a large vibration is caused by the water channel pulsation accompanying the vibration.

In addition, recently, the space between the leeward overhead line cable and the leeward side overhead cable has been arranged at a distance of about 8 to 10 times the diameter, and the leeward side overhead line cable has been replaced by the leeward overhead line cable. At the wake edge, a new unstable hydrodynamic vibration has been observed in which galloping vibration occurs on the leeward overhead line cable when the wind speed increases.

[0007] In order to reduce such vibration phenomena such as vortex excitation, an outer surface of a covering material for covering the erection cable is formed with irregularities such as projections and dimples. It is known to attach a cable covering tool provided with a concave and convex pattern.

[0008]

However, since the cable covering device is made of, for example, a synthetic resin, it cannot effectively suppress particularly large-amplitude vibrations. Also, the durability of the fixture for attaching the covering material is low.

Also, in order to provide the covering material integrally with the erection cable, the equipment for manufacturing the erection cable becomes large, which is uneconomical in terms of processing cost and equipment cost.

[0010] Further, it is difficult to predict vibration suppression measures, and it is often impossible to determine what vibration suppression measures are necessary unless construction cables are actually installed on site. Taking measures to control vibration was uneconomical.

Therefore, the present invention can effectively exhibit a vibration damping effect even with respect to large amplitude vibration phenomena such as wake galloping and rain vibration.
Another object of the present invention is to provide a cable covering material which is economical in terms of workability and processing cost.

[0012]

The cable covering device of the present invention is a rubber cable covering device which can be attached to the outer periphery of an erection cable and has an uneven surface integrally formed on the outer surface thereof. That is, this cable covering device controls the flow of air around the cable by the convex or concave portions formed on the outer surface, and regulates the water path of rainwater to suppress the occurrence of vibration factors such as vortex excitation. Further, since the cable covering member is made of rubber, its flexibility allows local deformation such as following aerodynamics, and exerts an effective vibration damping action even with large amplitude vibration.

[0013] The cable covering device is formed by, for example, extrusion molding and has a continuous uneven pattern in the longitudinal direction.

The cable covering device has a slit formed in the longitudinal direction of the cable, and is fitted to the cable body while widening the slit, and the slit portion is fastened.
It is desirable that the cable is attached to the cable body because the cable can be attached after cable construction by utilizing the flexibility of rubber, and the attaching operation can be simplified.

A plurality of cable covering members obtained by dividing the cable covering member in the circumferential direction may be attached in combination around the cable body.

[0016] In the cable covering device, for example, a rubber material is discharged while rotating a discharge port of an extruder to integrally form a spiral concavo-convex pattern continuous in a longitudinal direction on an outer surface of a substantially cylindrical shape. Things. Further, the cable covering device is, for example, a device in which a rubber material is discharged while oscillating a discharge port of an extruder, and a wavy uneven pattern continuous in a longitudinal direction is integrally formed on an outer surface of a substantially cylindrical shape. .

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a cable covering device according to the present invention will be described with reference to the drawings.

The cable covering device 1 according to the first embodiment comprises:
As shown in FIG. 1 (a), a substantially cylindrical member made of rubber, which is a flexible material, is provided with a projection 2 continuously formed in the longitudinal direction on the outer surface, and a slit 3 is formed in the longitudinal direction. Is formed.

The erection cable main body 4 is, for example, a cable used for a cable-stayed bridge, and has an outer surface of a cable strand 5 covered with a polyethylene resin 6.

As shown in FIGS. 1 (a) and 1 (b), the cable covering device 1 is obtained by expanding the slit 3 and fitting it into the erected cable body 4, and joining the portion of the slit 3 by heat welding and an adhesive. It is. In addition, other mounting methods of the cable covering tool 1 are as follows. A belt is wound around the cable covering tool 1 fitted into the erection cable main body 4 and fixed, or both ends of the connecting tool bridged between the slits 3 are bolt nuts or the like. Can be fastened and fixed. Although illustration is omitted,
For example, stoppers or the like may be attached to the upper end and the lower end of the cable covering device 1 so that the attachment position of the cable covering device 1 does not move in the longitudinal direction of the cable main body 4.

The projections 2 formed on the outer surface of the cable jacket 1 can control the air flow around the erection cable to suppress the vortex excitation and the wake galloping phenomenon, and can also regulate the formation of the water channel of the rainwater flowing on the outer surface. The occurrence of rain vibration can be suppressed.

Since the cable jacket 1 is made of rubber, its flexibility allows local deformation such as following aerodynamics, and is effective even when a large-amplitude vibration phenomenon occurs. The effect can be exerted. (If it can cope with large-amplitude vibrations, please add an appropriate specific example.) Also, as described above,
Can be easily attached even after the cable-stayed bridge has been installed, so that the erection cable body 4 can be attached to a required part according to the occurrence of vibration after the cable-stayed bridge is installed. Further, since the mounting is simple, it can be mounted even in a place where the interval between the parallel cables is small.

As another embodiment of the cable covering device 1 having a different shape of the projection 2, as shown in FIG. 4, a cable covering device 31 having a projection 32 continuous in a spiral shape in the longitudinal direction on an outer surface thereof. Alternatively, as shown in FIG. 5, there is a cable covering member 33 having an irregularly wavy projection 34 continuous on the outer surface in the longitudinal direction of the cable.

The cable jackets 31, 3 shown in FIGS.
In No. 3, since the projections 32 and 34 are formed around the cable, a constant vibration damping effect can be expected even if the direction of the wind changes. Further, since the cable covering members 31 and 33 are made of rubber, they can cope with large amplitude vibrations due to their flexibility.

The above-mentioned cable jacket (1, 31, 33)
Can be manufactured by, for example, extrusion molding. In FIG. 2 showing the extruder 10, reference numeral 11 denotes a popper for charging the rubber material 9, 12 denotes an extruder, 13 denotes a screw for extruding the rubber material 9, 14 denotes a driving device for rotating the screw, and 15 denotes a rubber material. Heater for melting 9,
Reference numerals 16 and 17 denote dies attached to the discharge port, 18 denotes a cooling section and a take-up section, 19 denotes a motor for rotating the die 17, and 28 and 29 denote sealing members.

Of the two dies 16 and 17 attached to the discharge port of the extruder 10, the die 16 on the extruder 12 side is a fixed die 16 fixed to the discharge port. Is provided at the center of the core 13 with a core 13 extending in the traveling direction of the rubber material 9. The core 13 is a member for forming the inner peripheral surface of the cable covering tool 1, is a columnar member having substantially the same diameter as the erected cable body 4, and extends to the vicinity of the cooling unit 18.

The tip die 17 is a rotary die rotatably attached to the fixed die 16, and is rotatably mounted at the tip of the fixed die 16 as shown in FIG. Further, it is connected to a motor 19 via a belt 20 so as to rotate at a predetermined peripheral speed.

As shown in FIG. 3A, the rotary die 17 has four concave portions 17a for forming the projections 2 on the inner peripheral surface of the circular rubber material introduction portion 17b.

The extruder 10 discharges the rubber material 9 while rotating the rotary die 17 at a predetermined peripheral speed, thereby forming the cable covering device 3 having the spiral projections 32.
1 can be formed. The spiral pitch of the spiral projection 32 can be controlled by the ratio between the peripheral speed of the rotary die 17 and the speed of discharging the rubber material by the screw 13. Note that the slit 3 of the cable jacket 1 is formed by cutting the cable jacket 1 in the longitudinal direction after molding.

Further, in this extruder 10, the rubber material 9 is discharged in a state where the rotary die 17 at the discharge port is kept stationary, so that a projection straight on the outer surface in the longitudinal direction as shown in FIG. 2 can be formed. Further, by discharging the rubber material 9 while oscillating the rotary die 17 of the discharge port, FIG.
As shown in FIG. 7, a cable covering member 33 having a wavy projection 34 continuous on the outer surface in the longitudinal direction of the cable can be formed.

Next, a cable covering device according to a second embodiment will be described.

As shown in FIG. 6, the cable cover 41 has a recess 42 formed in the outer peripheral surface of the cable cover 41 in the longitudinal direction. The recess 42 can be formed by, for example, the extruder 10 shown in FIG.
The rotary die 17 attached to the discharge port is provided on the inner peripheral surface of the rubber material introduction portion 21b as shown in FIG.
Can be manufactured by exchanging the rotary die 21 having the convex portion 21a for forming the rubber material 9 and discharging the rubber material 9 with the rotary die 21 stationary. Similarly, the cable cover 41 can control the flow of air around the cable by the concave portion 42 and regulate the water path of the rainwater, so that the occurrence of vibration factors such as vortex excitation can be suppressed. And, since the cable covering member 41 is made of rubber, its flexibility allows local deformation to follow aerodynamics, and can exert an effective vibration damping action even with large amplitude vibration. . The cable cover 41 can be attached to the cable main body 4 by widening the slit 3 provided in the longitudinal direction and fitting the slit 3 into the cable main body 4 and bonding the slit portion 3 with an adhesive or the like. The slit 3 of the cable covering tool 41 can be formed in the longitudinal direction after the cable covering tool 41 is formed.

By discharging the rubber material 9 while rotating the rotary die 21 at the discharge port in the extruder 10, a concave portion 44 spirally continuous in the longitudinal direction is formed on the outer surface as shown in FIG. The provided cable covering tool 45 can be formed.

The spiral pitch of the recess 44 can be controlled by the ratio between the peripheral speed of the rotary die 21 and the speed of discharging the rubber material by the screw 13.

Further, by discharging the rubber material 9 while oscillating the rotary die 21 at the discharge port in the extruder 10, as shown in FIG. 8, the outer surface has a continuous wavy shape in the longitudinal direction of the cable. The cable covering tool 47 having the concave portion 46 can be formed.

The shape of the concave portions 44 and 46 can be expected to have a constant vibration damping effect even when the wind direction changes, and can cope with large amplitude vibrations because the cable covering member is made of rubber.

Although the embodiment of the cable covering device of the present invention has been described above, the present invention is not limited to the above embodiment.

For example, the cable covering device may be attached to the cable body by combining a plurality of members divided in the circumferential direction around the cable body and bonding the divided portions.

As described above, the uneven pattern is not limited to a pattern that is continuous in the longitudinal direction. For example, a dimple pattern or irregular protrusions may be formed.

[0040]

The cable covering device of the present invention is a rubber cable covering device which can be attached to the outer periphery of an erection cable and has an outer surface integrally formed with an uneven pattern. The flow of air around the cable is controlled by the protrusions or the recesses, and the flow of rainwater is regulated, so that the occurrence of vibration factors such as vortex excitation can be suppressed. Also,
Because the cable jacket is made of rubber, its flexibility allows local deformation that follows aerodynamics, and it can exert an effective vibration damping action even for large amplitude vibrations.
Moreover, the durability can be improved without damaging the erection cable main body.

Also, the cable covering device has a slit formed in the longitudinal direction of the cable, and can be attached to the cable main body by widening the slit, fitting the cable main body, and fastening the slit portion. The mounting operation can be simplified using the flexibility. Further, it can be partially attached to the erection cable main body.

[Brief description of the drawings]

FIG. 1A is a perspective view showing a cable jacket having a continuous projection in a longitudinal direction and a cable body according to an embodiment of the present invention, and FIG. 1B is a perspective view showing the cable jacket shown in FIG. The perspective view showing the state where it was attached to the cable main part.

FIG. 2 is a cross-sectional view showing an extruder for manufacturing a cable covering device according to an embodiment of the present invention. (A) is an AA arrow sectional drawing which shows the mechanism which rotates a rotating die.

FIG. 3A is a cross-sectional view illustrating a cross-sectional shape of a rotary die when a projection is formed, and FIG. 3B is a cross-sectional view illustrating a cross-sectional shape of the rotary die when a concave portion is formed.

FIG. 4 is a perspective view showing a state in which a cable covering device having a spiral projection according to one embodiment of the present invention is attached to a cable main body.

FIG. 5 is a perspective view showing a state in which a cable covering device having a wavy projection according to one embodiment of the present invention is attached to a cable main body.

FIG. 6 is a perspective view showing a state in which a cable covering device having a longitudinally continuous concave portion according to one embodiment of the present invention is attached to a cable main body.

FIG. 7 is a perspective view showing a state in which a cable covering device having a spiral concave portion according to one embodiment of the present invention is attached to a cable main body.

FIG. 8 is a perspective view showing a state in which a cable covering device having a wavy concave portion according to one embodiment of the present invention is attached to a cable main body.

9A is a diagram illustrating vortex excitation generated in an installation cable, FIG. 9B is a diagram illustrating wake galloping generated in the installation cable, and FIG. 9C is a diagram illustrating rain vibration generated in the installation cable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cable-covering tool provided with protrusion continuous in the longitudinal direction 2 Projection 3 Slit 4 Cable main body 5 Cable strand 6 Cable-covering material (polyethylene) 10 Extruder 16 Fixing die 17 Rotating die 31 Cable with helical protrusion Covering device 32 Spiral protrusion 33 Cable covering device with wavy protrusion 34 Wavy protrusion 41 Cable covering device continuous in the longitudinal direction 42 Depression 44 Spiral depression 45 Cable covering device with spiral depression 46 Wavy 47 Cable covering with wavy recess

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) B29K 21:00 B29K 21:00 105: 20 105: 20 F term (reference) 2D059 AA41 BB06 BB08 GG02 GG06 GG23 GG61 3J048 AB03 AB05 BA25 DA06 EA07 EA39 4F207 AA45 AD15 AG04 AG05 AG14 AG28 AH35 KA01 KA17 KB18 KL80

Claims (6)

[Claims] 1. A cable which can be attached to the outer periphery of an installation cable,
A rubber cable sheathing with an uneven pattern integrally formed on its outer surface. 2. The cable covering device according to claim 1, wherein said cable covering device is formed by extrusion molding, and has an uneven pattern continuous in a longitudinal direction. 3. The cable covering device has a slit formed in a longitudinal direction of the cable, and is fitted to a cable body while widening the slit, and the slit portion is fastened.
The cable jacket according to claim 1 or 2, wherein the cable jacket is attached to a cable body. 4. A cable covering device according to claim 1, wherein a plurality of cable covering members obtained by dividing the cable covering device in a circumferential direction are attached around a cable body. 5. The method according to claim 1, wherein the rubber material is discharged while rotating the discharge port of the extruder, and a spirally concave and convex pattern continuous in the longitudinal direction is integrally formed on the outer surface of the substantially cylindrical shape. 5. The cable covering tool according to any one of 1 to 4. 6. A process according to claim 1, wherein the rubber material is discharged while oscillating the discharge port of the extruder to integrally form a wavy uneven pattern continuous in the longitudinal direction on the outer surface of the substantially cylindrical shape. 5. The cable covering tool according to any one of 1 to 4.