JP3390733B2 - Optical fiber cable laying method and overhead vehicle used for the laying method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for laying an optical fiber cable and an overhead line vehicle used for the laying method.

[0002]

2. Description of the Related Art In recent years, in response to higher speed and larger capacity of communication, a cable having a conductor of metal, for example, a copper wire covered with plastic or the like, is replaced with a paired wire composed of one pair or a plurality of pairs. Optical fiber cables are laid to construct a communication cable network.

At the time of laying this optical fiber cable, the optical fiber cable is inserted into the surplus space of the filling hole pipe line in which the pair wires are already arranged and buried in the ground. That is, the operator is placed in each manhole through which the laying route of the optical fiber cable is communicated, while the feeding drum of the optical fiber cable is arranged facing the starting end side manhole and the wire extension rope is facing the ending side manhole. The take-up drum is installed, and one end of the extended rope is pushed from the manhole on the starting end side to the laying pipeline, and the workers in each manhole pull out together based on the contact from the worker on the ground, and they are successively adjoined. Insert an extended rope into the laying pipeline between the manholes. Then, the optical fiber cable is connected to the other end of the extended wire rope, the optical fiber cable is similarly pulled out, and the optical fiber cable is inserted through the set laying pipeline.

For convenience of description, the extended rope and the optical fiber cable will be collectively referred to as a cable hereinafter, unless the extended rope or the optical fiber cable is distinguished.

[0005]

However, in the method of laying the cable by manually pulling out the cable and inserting it into the laying pipeline, the pulling speed is 7 to 8 m / min, and the average of one worker is Since the effective traction capacity is 300 N, the traction capacity is limited. For example, if the traction force is T, the friction coefficient is μ, the weight per unit length of the cable is W, and the length is L, then T = μ · W · L. Can't be big. In addition, if the weight per unit length of the cable is large, specifically, if the number of cores of the optical fiber is large,
The length of conduit that can be towed becomes shorter. For this reason, when laying the cable, approximately 500 m is set as one section, and construction is performed for about 8 hours.

When it is necessary to lay a cable over a pipeline length exceeding 500 m, as shown in FIG. 6, the feeding drum 6 is arranged in the manhole M located substantially in the middle of the laying pipeline P and laid. The section is divided, and the cable C is laid in one of the divided sections A, then the cable C necessary for laying the other section B is unwound to the ground, and its end is laid in the other section B. . However, even if the laid pipeline P is divided, the pipeline length cannot be significantly extended. Therefore, the optical fiber cable must be connected for each set pipeline length, and the reliability decreases. At the same time, there is a problem that the work becomes complicated. In addition, a large number of workers have to be arranged in the manhole M, etc., and a lot of work time is required, resulting in a high cost as a whole.

In order to cope with such a problem, as shown in FIG. 7, an intermediate tractor 1 called an optopooler is installed in a manhole M at set intervals and a cable C is laid by the intermediate tractor 1. Proposed.

Although not shown in detail, the intermediate tractor 1 has a pair of endless belts arranged to face each other, a cable C is sandwiched by the pair of endless belts, and the pair of endless belts is circulated. The cable C is towed in sequence and fed out backwards, with a maximum towing force of 2 kN,
It has a maximum traction speed of 20 m / min. And
The intermediate traction machine 1 is provided with a tension sensor 2 that faces the exit on the winding side and detects the tension of the cable C. As shown in FIG. 8, the tension sensor 2 includes a detection roller 3 and a load cell 4 that detects the vertical component force of the tension acting on the detection roller 3, and the tension acting on the cable C is calculated from the vertical component force. To grasp.

In the manhole M where the intermediate tractor 1 is not installed, wire extension auxiliary equipment 5 is installed facing each laying pipe P opening in the manhole M. Although not shown in detail, the wire extension auxiliary equipment 5 includes a support pipe installed between the ceiling and the floor in the manhole M, or between both side walls, and a four-sided roller fixed to the support pipe. , The cable C is guided between the laying pipes P, P that open to each manhole M. Therefore, the wire extension auxiliary equipment 5
For the manhole M installed with, the manhole cover M1
It can be closed by means of, which does not obstruct the passage of people or vehicles and also eliminates the need for staffing.

When the cable C is laid by the intermediate towing machine 1 as described above, the tension sensor 2 detects the tension of the cable C, so that the pulling state of the cable C can be grasped. It is possible to automatically pull the cable C by controlling the pulling speed of the machine 1.

Specifically, as shown in the flow chart of FIG. 9, when the automatic operation is started (step S1), the automatic operation standby state is set (step S2), and the intermediate tractor 1 on the tip side starts the operation. Accordingly, when the tip tension of the cable C rises (step S3), the tension sensor 2 detects the slack (vertical component force) of the cable C on the winding side, and compares the vertical component force with the acceleration target value ( If the vertical component force exceeds the acceleration target value in step S4), the acceleration operation is performed up to the maximum traction speed (20 m / min) (step S5), while the vertical component force does not exceed the acceleration target value. Returns to step S3 and is repeated until the vertical component force exceeds the acceleration target value.

After performing the acceleration operation, the vertical component force is compared with the acceleration target value (step S6). If the vertical component force is less than the acceleration target value, the traction set to be smaller than the maximum traction speed. The deceleration operation within the speed (19 m / min) is performed (step S7). On the other hand, when the vertical component force is not less than the acceleration target value, the process returns to step S5 to continue the acceleration operation.

Next, after the deceleration operation is performed, the vertical component force is compared with the stop determination value (step S8). If the vertical component force is less than the stop determination value, the traction speed is controlled to be constant (step S8). S9), stop determination time and set time (0.3
Seconds) are compared (step S10), and when the stop determination time is equal to or longer than the set time, the operation of the intermediate tractor 1 is stopped,
The process returns to step S2 in the automatic driving standby state. If the stop determination time is not longer than the set time, the process returns to step S8 and the vertical component force is compared with the stop determination value.

On the other hand, in step S8, if the vertical component force is not less than the stop determination value, the vertical component force is compared with the acceleration target value (step S11), and if the vertical component force is less than the acceleration target value, the towing is performed. Control the speed constant (step S
9) If the vertical component is not less than the acceleration target value,
Returning to step S5, acceleration operation is performed.

When such an intermediate tractor 1 is used,
One intermediate traction machine 1 can handle the traction force of about 7 workers, and can be constructed at a speed three times as fast as manual traction. As a result,
The number of workers can be reduced as compared with the case where the cable C is manually laid, and the cable C can be laid in a short time, and the cost can be significantly reduced. Further, since the cable C can be laid over a longer distance, the number of connection points can be reduced and the reliability can be improved.

However, even when the cable C is laid using the intermediate traction machine 1, there is a limit to the maximum traction force of the intermediate traction machine 1. For example, if the number of optical fiber cores increases, the unit length thereof increases. The weight per hit becomes large, and as described above, the length of the cable C that can be towed by one unit by being defined by the maximum towing force of the intermediate towing machine 1 becomes short. In this case, the intermediate traction machine 1 must be installed in the manhole M at shorter intervals, and the intermediate traction machine 1 must be removed from the manhole M when the construction is completed. Therefore, much time is required for disassembling and assembling the intermediate traction machine and installing the intermediate traction machine.

Further, in order to lay the cable C over a longer distance, many intermediate traction machines 1 must be installed at intervals corresponding to the line type of the optical fiber cable. It is necessary to secure a worker who manages, and the increase in cost cannot be avoided.

The present invention has been made in view of the above problems, and an optical fiber cable is laid over a longer distance by using an overhead line vehicle having a larger traction force together with an intermediate traction machine to improve reliability. It is intended to provide a method for laying an optical fiber cable which can be improved.

The present invention also provides an overhead car used in the method of laying an optical fiber cable.

[0020]

SUMMARY OF THE INVENTION The present invention relates to a method for laying an optical fiber cable over a set manhole and a laying conduit between manholes, in which a delivery drum having the optical fiber cable wound facing a starting end side manhole is provided. While arranging, an intermediate tractor equipped with a tension sensor that detects the tension of the wire rope and the optical fiber cable at the exit on the winding side is installed in the manhole at a set interval corresponding to the line type of the optical fiber cable, In addition, a tension sensor that detects the tension of the wire rope is installed at the entrance on the winding side, and an overhead wire car that rotates the winding drum mounted rotatably in the winding direction is arranged facing the end-side manhole. Intermediately extends the wire rope while controlling the traction of the intermediate traction machine based on the tension generated by the traction of the intermediate traction machine in the subsequent stage. While pulling by the pulling machine, the tip of the pulled wire rope is fixed to the winding drum of the overhead car via the tension sensor, and the pulling of one intermediate pulling machine is generated by the pulling of the intermediate pulling machine of the subsequent stage. Based on the tension
Alternatively, while controlling the interlocking control based on the tension generated by the rotation of the take-up drum, the take-up drum is rotated at a set number of revolutions to wind up the wire-drawing rope, and is connected to the wire-drawing rope and the wire-drawing rope by an intermediate traction machine. The pulled optical fiber cable is pulled, and the optical fiber cable is inserted through the set laying pipeline.

According to the present invention, the winding speed of the winding rope of the overhead wire car is prevented from exceeding the winding speed of the winding rope and the optical fiber cable by the intermediate traction machine due to the rotation of the winding drum. While controlling the rotation and the traction of the intermediate traction machine by rotating the winding drum at a set number of revolutions to wind the wire rope, by pulling the wire rope and the optical fiber cable by the intermediate traction machine, The optical fiber cable can be laid over a long-distance laying pipeline, and the connection points of the optical fiber cable can be reduced to improve reliability.

In the present invention, when the wire rope is wound around the winding drum, and then the optical fiber cable having a constant length is directly wound around the winding drum without the tension sensor, the optical fiber cable is terminated. It can be used when it is necessary to pull out a certain length from the manhole to the ground and connect to the target.

Further, the present invention is an overhead line vehicle used in the method of laying an optical fiber cable according to claim 1, and is driven via a winding drum rotatably mounted on the vehicle body and an engine. The hydraulic pump, the hydraulic motor driven by the pressure oil discharged from the hydraulic pump to rotate the winding drum in the winding direction, the electromagnetic relief valve provided in the discharge circuit of the hydraulic pump, and the winding drum. A tension sensor that detects the tension of the drawn wire rope,
A low speed actuator that speeds up the engine to a first set speed, a high speed actuator that speeds up to a second set speed, and a changeover switch that selectively switches between the low speed actuator and the high speed actuator. At least equipped, when the tension above the allowable tension set by the tension sensor is detected, the electromagnetic relief valve is controlled via the control device to bypass the hydraulic fluid discharged from the hydraulic pump and rotate the take-up drum by the hydraulic motor. On the other hand, while switching from the high speed actuator to the low speed actuator via the changeover switch in accordance with the winding distance of the wire rope wound around the winding drum, the engine is switched from the second set speed to the first speed. It is characterized by decelerating to a set rotation.

According to the present invention, when the wire rope is wound around the winding drum of the overhead car, if the tension above the set allowable tension is detected, the rotation of the winding drum is stopped. It is possible to reliably prevent the fiber cable from being overloaded so as to exceed its allowable tension. Further, when the winding speed is gradually increased by winding the drawn wire rope, it is possible to prevent the winding speed from exceeding the maximum traction speed of the intermediate tractor.

[0025]

In the present invention, the discharge line of the hydraulic pump is provided with an electromagnetic switching valve which is directly connected to the hydraulic motor in the neutral position and is connected to the hydraulic motor via the relief valve in the switching position. If the set pressure is set according to the allowable tension of the optical fiber cable, the allowable tension of the optical fiber cable will be increased when the extended cable is wound and then the fixed length of the optical fiber cable is wound on the winding drum. It can be wound so that it does not exceed.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an outline of a method of laying an optical fiber cable according to the present invention.

In FIG. 1, adjacent manholes M, M
A laying pipeline P buried in the ground is connected between them, and one end and the other end of each laying pipeline P are opened to each manhole M. Therefore, the laid pipes P are communicated with each other through the manhole M. Since the cable C is laid over the set pipeline length, the intermediate traction machine 1 is installed in the manhole M at set intervals corresponding to the line type of the optical fiber cable, and the intermediate traction machine 1 is also installed. In the manhole M where no
Is installed. Further, the pay-out drum 6 around which the optical fiber cable is wound is arranged so as to face the starting end side manhole M, while the overhead car 10 faces the ending side manhole M.
Are arranged.

Here, the intermediate traction machine 1 and the wire-drawing auxiliary equipment 5 are the same as those described above, and a detailed description thereof will be omitted.

The overhead car 10 has a maximum traction force of 6 kN, and as shown in FIG. 2, the winding drum 7 is rotatably mounted on the vehicle body 11, and the supporting columns 12 erected on the vehicle body 11 are installed. A tension sensor 13 for detecting the tension of the wire rope is provided. Then, in order to drive the take-up drum 7 to rotate, a hydraulic pump 14 connected to the engine E via a power take-out device (PTO) (not shown), and hydraulic oil supplied from the hydraulic pump 14 to rotate the hydraulic oil are supplied. Although not shown in detail, a motor 15 is provided, and an endless chain is wound between the rotary shaft connected to the winding drum 7 and the output shaft of the hydraulic motor 15 to rotate the hydraulic motor 15. As a result, the winding drum 7 can be rotated in the winding direction of the wire rope.
Further, the discharge circuit of the hydraulic pump 14 is provided with an electromagnetic relief valve 16 capable of arbitrarily adjusting the set pressure and an electromagnetic switching valve 17. The electromagnetic switching valve 17 is a two-position switching valve whose discharge port is directly connected to the hydraulic motor 15 when in the neutral position, and the discharge port is a relief valve when the neutral position is switched to the switching position. It is connected to the hydraulic motor 15 via 18. In addition, 19 is a hydraulic oil tank.

On the other hand, the overhead vehicle 10 is provided with a control device 20. The control device 20 includes a CPU unit 2
1, an amplifier 22 that amplifies the signal of the CPU unit 21 and outputs it to the electromagnetic relief valve 16 and the electromagnetic control valve 17, a display device 23 that displays the tension detected by the tension sensor 13, and the setting of the electromagnetic relief valve 16. It has a volume 24 for adjusting the pressure.

The tension sensor 13 has the same structure as the tension sensor 2 of the intermediate traction machine 1 described above, and the tension acting on the wire rope is detected via a load cell (not shown).

The accelerator lever (not shown) of the engine E has a low speed actuator 25 for increasing the engine speed from the idling state to the first set speed.
And a high speed actuator 26 for increasing the speed to a second set speed are connected.
When 5, 26 are activated, the engine E can be accelerated to the first set speed or the second set speed, respectively. Here, the actuators 25 and 26 are selectively operated via the changeover switch 27.

Next, a method of laying the cable C over the laying pipeline P set by using the overhead vehicle 10 and the intermediate tractor 1 will be described.

First, the feeding drum 6 around which the optical fiber cable is wound is arranged facing the starting end side manhole M, and the overhead car 10 is arranged facing the ending end side manhole M. Further, the intermediate tractor 1 is installed in the manhole M at set intervals according to the line type (the number of core wires) of the optical fiber cable, the presence or absence of a curved portion of the conduit P, the radius of curvature thereof, the gradient of the conduit P, and the like. To do.

Further, the wire-drawing auxiliary equipment 5 is installed in the manhole M where the intermediate tractor 1 is not installed, and when the installation is completed, the manhole M is closed by the manhole cover M1.

If the intermediate towing machine 1 is installed at a set interval and the wire-drawing auxiliary equipment 5 is installed in the other manholes M, first, the wire-drawing rope is unwound and laid so that the manhole M on the starting end side is opened. Push it into one end of the conduit P. When the wire-drawing rope reaches the first intermediate traction machine 1 through the wire-drawing auxiliary equipment 5, the intermediate traction machine 1 automatically pulls the wire-drawing rope at a constant speed and feeds it out, and then, through the wire-drawing auxiliary equipment 5. Insert the wire rope to the next intermediate tractor 1.

When the wire-drawing rope is inserted to the next intermediate traction machine 1, the intermediate traction machine 1 at the preceding stage and the intermediate traction machine 1 at the subsequent stage cooperate to move the wire-drawing rope to the next intermediate traction machine 1. Let out. That is, as described above with reference to the flowchart of FIG. 9, when the tension acting on the tension sensor 2 of the intermediate tractor 1 in the preceding stage is detected by the pulling of the wire rope by the intermediate tractor 1 in the subsequent stage, the setting is performed. If the tension on the winding side is less than the target value, the maximum traction speed is reached if the tension is less than the target value. The deceleration operation is performed within the limit of the set traction speed. And
When the state below the target value continues for a certain period of time or more, the pulling of the wire rope is stopped until the tension is restored to the set target value, and when the tension is restored, the pulling work is restarted.

In the same manner, when the wire ropes sequentially pulled through the intermediate towing machine 1 reach the terminal side manhole M, the wire ropes are pulled to the ground and the wire ropes are passed through the tension sensor 13 of the overhead car 10. And fasten it to the winding drum 7.

Next, the control for winding the cable C in cooperation with the overhead car 10 and the intermediate tractor 1 will be described with reference to the flowchart of FIG.

First, the intermediate towing machine 1 is set to the automatic operation mode (step S21). Also, the overhead car 10
In step S22, the control device 20 is set via the volume 24 corresponding to the allowable tension of the line type of the optical fiber cable to be laid (step S22), and the engine E is started (step S23). In this state, if a start switch (not shown) is operated, the hydraulic pump 14 is driven by the engine E and pressure oil is supplied to the hydraulic motor 15 via the electromagnetic control valve 17 in the neutral position, so that the hydraulic motor 15 rotates. The winding drum 7 can be driven and rotated.
As a result, the wire rope can be wound around the winding drum 7 (step S24).

When the winding of the wire rope is started,
Grasp the current winding distance of the wire rope (step S
25) If it is less than the set distance, the changeover switch 27 is changed over to operate the high speed side actuator 26 (step S26). In addition, when winding a wire rope longer than the set distance, the changeover switch 2
7 is switched to operate the low speed side actuator 25 (step S27). As a result, the engine E is accelerated to the rotation speed set by the high speed side actuator 26 or the low speed side actuator 25, and the set rotation speed can be maintained. Therefore, the hydraulic pump 14 is also driven to rotate at a constant rotational speed, which is either an increased speed or a high speed or a low speed, and supplies the hydraulic motor 15 with a discharge amount of pressure oil corresponding to those rotational speeds to drive the hydraulic motor 15 at a high speed or a low speed. The wire rope can be wound around the winding drum 7 at a high speed or a low speed by being driven to rotate at a constant rotation speed.

That is, although the winding speed of the wire rope of the overhead car 10 is set to be less than the maximum traction speed of the intermediate traction machine 1, the winding of the wire rope around the winding drum 7 When the radius of rotation of the wire rope wound around the drum 7 becomes large, and the winding amount per one rotation, that is, the winding speed gradually increases even if the number of rotations is constant, and the pipe length is long, May exceed the maximum towing speed of the intermediate towing machine 1. Therefore, when the wire rope is wound for a set distance, the changeover switch 27 is changed over to operate the low speed side actuator 25 and set the engine speed to a low speed, thereby decreasing the speed of the hydraulic pump 14. When the discharge amount of the hydraulic pump 14 decreases, the rotation speed of the hydraulic motor 15 decreases, and the winding speed can be reduced.

In this way, the winding speed of the wire rope around the winding drum 7 is controlled so as not to exceed the maximum towing speed (20 m / min) of the intermediate towing machine 1.

In the case of the winding drum 7 of the present embodiment, when a wire rope having a diameter of 8 mm is used, the winding distance for switching from high speed to low speed is about 1000 m (see FIG. 4).

At this time, the winding distance of the wire extension rope can be detected by counting the connection points of the wire extension rope by connecting the wire extension rope of unit length.
It can also be detected based on which manhole M the starting end of the optical fiber cable connected to the extended cable has reached, based on the length of the laying pipe P that is grasped in advance.

On the other hand, the line rope is wound around the winding drum 7 by the overhead car 10 to control the towing speed of the intermediate towing machine 1 (step S28). That is, the tension associated with the winding speed of the wire rope of the overhead car 10 is detected by the tension sensor 2 of the intermediate traction machine 1 at the preceding stage, and as described above, when the tension exceeds the target value, acceleration operation is performed, When the tension is less than the target value, deceleration operation is performed, and if the predetermined time continues at that time, the pulling of the wire rope is stopped.

Further, in the intermediate towing machine 1, when the pulling speed is detected (step S29) and is higher than the winding speed of the catenary 10, the winding is within the set tension range of the catenary 10 and The vehicle is pulled at a speed according to the distance (step S30). On the other hand, when the pulling speed of the intermediate towing machine 1 is lower than the winding speed of the overhead line 10, the winding tension of the overhead line 10 increases (step S
31), and compared with the set tension of the overhead car 10 (step S
32) If the tension is equal to or more than the set tension, the winding of the overhead line vehicle 10 is stopped (step S33). If the tension is less than the set tension, the winding of the overhead line vehicle 10 is continued (step S3).
4) Then, returning to step S15, the same work is performed.

That is, as shown in FIG.
When the towing speed V2 of the intermediate towing machine 1 is higher than the towing speed V1 of the intermediate towing machine 1, the shared tension T2 of the overhead car 10 is added to the sharing tension T1 of the intermediate towing machine 1 to draw the vehicle. At this time, in the intermediate towing machine 1, since the cable C is held by the pair of endless belts, the cable C may be adversely affected. When the tension of the intermediate towing machine 1 increases and the towing work of the intermediate towing machine 1 is stopped, the shared tension T2 of the overhead car 10 and the resistance of the intermediate towing machine 1 are added to pull the cable. C may be adversely affected.

Therefore, the winding speed V2 of the overhead car 10
Is greater than the traction speed V1 of the intermediate traction machine 1, or when the intermediate traction machine 1 is temporarily stopped, the tension detected by the tension sensor 13 becomes larger than the set allowable tension. Therefore, the control device 20 compares the input tension with the set allowable tension, and when the detected tension is larger than the set allowable tension, outputs a control signal to the electromagnetic relief valve 16 via the amplifier 22. Then, the electromagnetic relief valve 16 is controlled to bypass the pressure oil discharged from the hydraulic pump 14 to the hydraulic oil tank 19, and the hydraulic motor 15
To stop the rotation of.

On the other hand, the towing speed of the intermediate towing machine 1 is the overhead line vehicle 1.
If the winding speed is greater than 0, the intermediate tractor 1
Although the slack of the cable C occurs at the rear of the cable, if the tension is within the set tension range of the overhead car 10, the overhead car 10 continues to wind the cable. However, as described above, when the winding distance exceeds the set distance, the maximum traction speed of the intermediate tractor 1 is exceeded, and therefore the winding is performed at a speed corresponding to the winding distance.

In this embodiment, for the maximum towing speed of the intermediate towing machine 1 of 20 m / min, the extension cable is 15
The winding speed at the time of winding at 00 m is set so as not to exceed 19 m / min.

When the pressure oil discharged from the hydraulic pump 14 rises above the pressure set in advance by the electromagnetic relief valve 16, the electromagnetic relief valve 16 operates to bypass the pressure oil to the hydraulic oil tank 19. , The rotation of the hydraulic motor 15 is stopped. Therefore, it is possible to prevent the hydraulic motor 15 from rotating with a high torque due to an abnormally high pressure and to apply a tension above the allowable tension to the optical fiber cable.

As described above, the intermediate traction machine 1 and the overhead vehicle 10 having a larger traction force than the intermediate traction machine 1 are used together, and the both are interlocked to pull the cable C to wind it. , Intermediate tractor over the set pipeline length 1
Compared to the case where the cable C is laid using only
There is no need to install one or more intermediate traction machines 1 in the latter stage of the intermediate traction machines 1 that need to be installed at a set interval corresponding to the line type of the optical fiber cable,
The work involved in the installation of the intermediate towing machine 1 and the operator involved in the management thereof are unnecessary, and the overall cost can be reduced. Further, when the same number of intermediate tractors 1 are used, a certain distance behind the intermediate tractors 1 can be laid by the overhead car 10, so that the distance that can be laid by one operation can be extended. Becomes Therefore,
The number of connecting points of the optical fiber cable is reduced, the reliability is improved, and the connecting work of the optical fiber cable is unnecessary.

By the way, when laying the optical fiber cable over the set section, the optical fiber cable is pulled out from the terminal side manhole M to the ground by a certain length.
For example, it may be necessary to connect to a target on the ground. In this case, the optical fiber cable cannot pass the tension sensor 13 due to the restriction of the allowable bending radius of the optical fiber cable.

Therefore, the overhead wheel 10 is moved so that the winding drum 7 faces the terminal-side manhole M, and the optical fiber cable is wound directly on the winding drum 7. When the optical fiber cable of a certain length is wound around the winding drum 7, the electromagnetic switching valve 17 is switched from the neutral position to the switching position via the control device 20, and the pressure oil is supplied to the hydraulic motor 15 via the relief valve 18.
Is to be supplied to. At this time, the set pressure of the relief valve 18 is set to a pressure corresponding to the allowable tension depending on the line type of the optical fiber cable. Therefore, when the optical fiber cable is wound around the winding drum 7, the pressure oil rises when a certain tension is applied, and when the set pressure is exceeded, the relief valve 18 bypasses the pressure oil to the hydraulic oil tank 19. Then, the rotation of the hydraulic motor 15 can be stopped. Therefore, even when the optical fiber cable of a certain length is wound up without passing through the tension sensor 13,
Never overload the optical fiber cable beyond the allowable tension.

[0058]

As described above, according to the method for laying the optical fiber cable of the present invention, the winding speed of the wire drawing rope due to the rotation of the winding drum of the overhead car is the wire drawing rope and the fiber optic cable by the intermediate traction machine. While controlling the rotation of the take-up drum and the traction of the intermediate traction machine so as not to exceed the traction speed of the By pulling the wire rope and the optical fiber cable, it is possible to lay the optical fiber cable over a longer laying pipeline, and it is possible to reduce the connection points of the optical fiber cable and improve the reliability. it can.

Further, according to the catenary used in the cable laying method of the present invention, when the wire rope is wound around the winding drum of the catenary, a tension above the set allowable tension is detected. Since the rotation of the winding drum is stopped, it is possible to reliably prevent the optical fiber cable from being overloaded so as to exceed its allowable tension. Further, when the winding speed is gradually increased by winding the drawn wire rope, it is possible to prevent the winding speed from exceeding the maximum traction speed of the intermediate tractor.

[Brief description of drawings]

FIG. 1 is a schematic view illustrating a method of laying an optical fiber cable according to the present invention.

FIG. 2 is a schematic view showing an overhead line vehicle used in the method for laying an optical fiber cable of the present invention together with a hydraulic circuit and a control circuit.

FIG. 3 is a flowchart for interlocking control of the intermediate traction machine and the overhead car in the optical fiber cable laying method of the present invention.

FIG. 4 is a characteristic curve diagram showing a relationship between a winding distance and a winding speed of an extended rope by an overhead car.

FIG. 5 is an explanatory diagram showing the relationship between the pulling speed and the tension of the intermediate traction machine and the overhead car in the method of laying the optical fiber cable according to the present invention.

FIG. 6 is a schematic view illustrating a conventional method of laying an optical fiber cable by human power.

FIG. 7 is a schematic diagram illustrating a method of laying an optical fiber cable using a conventional intermediate traction machine.

FIG. 8 is a flow chart for controlling the intermediate traction machine of FIG.

9 is a schematic diagram illustrating a tension sensor provided in the intermediate tractor of FIG. 7. FIG.

[Explanation of symbols]

1 Intermediate tractor 2 Tension sensor 5 Wire extension auxiliary equipment 6 Feeding drum 7 winding drum 10 overhead car 11 body frame 13 Tension sensor 14 Hydraulic pump 15 Hydraulic motor 16 Electromagnetic relief valve 17 Solenoid switching valve 18 relief valve 20 Control device 25 High speed actuator 26 Low speed actuator 27 Changeover switch P laying pipeline M manhole E engine

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masami Shimada, 3-3-22 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Kansai Electric Power Co., Inc. (72) Shoji Higashimori 3--3, Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture No. 22 In Kansai Electric Power Co., Inc. (72) Inventor Daishi Omori 3-3-3 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture No. 22 Inside Kansai Electric Power Co., Inc. (72) Yusuke Kitagawa 3-3 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture No. 22 Kansai Electric Power Co., Inc. (72) Inventor ▲ Hama ▼ Hideyuki Naka, 2-3-4, Honjo Higashi, Kita-ku, Osaka City, Osaka Prefecture Kindennai Co., Ltd. (56) Reference JP-A-5-30620 (JP, A) JP 59-35510 (JP, A) JP 3-190516 (JP, A) Actual opening 2-107209 (JP, U) Actual opening Sho 59-183117 (JP, U) Actual opening Sho 62 -26108 (JP, U) (58) Survey The field (Int.Cl. ^7, DB name) H02G 1/06 G02B 6/46

Claims (4)

(57) [Claims] 1. In a method of laying an optical fiber cable over a set manhole-to-manhole laying conduit, a delivery drum wound with the optical fiber cable is arranged facing the starting end side manhole, while a wire extension roll is arranged.
Tension sensor that detects the tension of the cable and the fiber optic cable.
An intermediate traction machine with a sir installed at the exit on the winding side
Manhole with a set interval according to the cable line type
The tension sensor that is installed in the
A sir is installed at the entrance on the winding side, and it can be rotated freely.
Overhead wire that rotates the mounted winding drum in the winding direction
Place the car so that it faces the terminal manhole, and the first intermediate traction machine
Is generated by the traction of the intermediate traction machine in the subsequent stage.
The wire rope is used as an intermediate traction machine while performing interlocking control based on force.
Therefore, while pulling, pull the tension at the end of the pulled wire rope.
Attach it to the take-up drum of the overhead car via the sensor,
Of the intermediate tractor of
The tension generated by the
Winding is performed with interlocking control based on the tension generated by rotation.
Rotate the take-up drum at the set speed and wind the wire rope.
A method of laying an optical fiber cable, characterized by pulling a wire rope and an optical fiber cable connected to the wire rope by an intermediate traction machine and inserting the optical fiber cable over a set laying pipeline. 2. A wire rope is wound around the winding drum.
After taking it, attach a certain length of fiber optic cable to the tension sensor.
The optical fiber cable laying method according to claim 1, wherein the optical fiber cable is directly wound around the winding drum without passing through the winding wire. 3. An overhead line vehicle used in the method for laying an optical fiber cable according to claim 1, wherein the winding drum is rotatably mounted on the vehicle body, and a hydraulic pump is driven via an engine. A hydraulic motor driven by pressure oil discharged from the hydraulic pump to rotate the winding drum in the winding direction, an electromagnetic relief valve provided in the discharge circuit of the hydraulic pump, and a wire rope wound around the winding drum. Tension sensor that detects the tension of the
Low speed actuator to increase the set speed of
High-speed actuator for increasing the speed to the second set speed
And these low speed actuators or high speed actuators
At least a selector switch for selectively switching the user, and when a tension above the allowable tension set by the tension sensor is detected, the electromagnetic relief valve is controlled via the control device to control the discharge pressure oil of the hydraulic pump. Bypass and stop the rotation of the take-up drum by the hydraulic motor .
For high speed via the changeover switch according to the winding distance
Switch from actuator to low speed actuator,
Decelerate the engine from the second set speed to the first set speed
An overhead line car used in the method of laying an optical fiber cable. 4. An electromagnetic switching valve, which is directly connected to the hydraulic motor at a neutral position and is connected to the hydraulic motor at a switching position via a relief valve, is provided in a discharge line of the hydraulic pump.
Overhead line vehicle set pressure of the relief valve is used in the laying method of the optical fiber cable of claim 3 Symbol mounting, characterized in that it is set corresponding to the permissible tension of the optical fiber cable.