JPH0145211Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a method for laying cables and other long bodies along conduits or troughs installed underground, or for scattering existing long bodies. The present invention relates to an improvement of a traction device for a long body used in the event.

BACKGROUND OF THE INVENTION Conventionally, a cable pulling machine as shown in FIG. 1 has been used to remove elongated bodies such as electric cables (hereinafter simply referred to as cables) installed in underground pipes or the like.

This cable traction machine 1 includes a guide shaft 4 attached to a manhole wall 3 at the end of a cable laying conduit 2 in parallel with the conduit 2, and a front movable section attached movably along the guide shaft 4. Frame 5 and rear moving frame 6, and these front and rear moving frames 5, 6
A net 8 is stretched between the nets 8 and 7, through which the cables 7 are inserted, and when the nets 8 are expanded and contracted, they grip the cables 7 [see Fig. 1b], and when they are retracted, they release the grip [Fig. 1]. a gripping cylinder mechanism 9 supported by the manhole wall 3 and connected to the front moving frame 5 to move the net 8 forward when the net 8 is in the gripping state [see FIG. 1c]; The net 8 is retracted when the net 8 is in the released state (see FIG. 1a) and a traction cylinder mechanism 10. That is, the cable 7 is pulled along the conduit 2 by sequentially repeating the operations shown in FIGS. 1A to 1D.

On the other hand, the inventor of the present application has proposed the above-mentioned cable traction machine 1.
He proposed a method of pulling cables into underground conduits, etc. using a cable (Japanese Patent Application No. 58-7730, ``Method of laying a long body''). In this method, a pulling machine such as a winch is installed at the front end of an underground pipe, etc., and the above-mentioned cable pulling machine is installed at multiple manholes etc. in the middle of the pipe.
This is a method in which the cable is pulled and laid in front of the conduit by the cable pulling machine and the cable pulling machine, with the timing of the back-and-forth movement and the stroke of the back-and-forth movement of the nets of these cable traction machines being matched. This method reduces the tension that occurs in the cable when it is pulled in, making it possible to smoothly pull the cable into a long-distance conduit.

However, since the above-mentioned pulling machine is a device that pulls the cable continuously, and the cable pulling machine is a device that pulls the cable intermittently, it is difficult to adjust the speed of the cable pulling machine and the cable pulling machine. During the gripping process [in the state shown in Figure 1 b], the pulling force of the pick-up machine acts, and the net 8
The cable 7 held by is facing forward [in the direction of arrow A]
If the cable 7 is pulled too tightly, the net 8 will be dragged by the cable 7 and contract, and there is a risk that the cable 7 will not be fully gripped by the net 8. If the net 8 is moved forward in this state, the cable 7 and the net 8 may stall, causing damage to the outer sheath of the cable 7, or causing problems such as the cable 7 not being pulled by the cable pulling machine. There was a possibility.

The present invention was developed against the background of the above-mentioned circumstances, and aims to provide a long traction device that can reliably grip and pull a cable when external force is easily applied to the cable to be towed in the traction direction. This is the purpose.

The present invention will be explained below based on an embodiment shown in FIGS. 2 to 4.

Reference numeral 11 in the figure indicates an elongated traction device according to an embodiment. In the example shown, manhole 12A,
It is installed on wall 3 of 12B. Moreover, the code 13 is
It is a drum for cable storage installed at the rear end of the conduit 2, and the rear end of the guide rope 14 is connected to the tip of the cable 7 wound around this drum 13.
The tip of this guide rope 14 is the manhole 12
It is connected to a take-up machine 15, such as a winch, installed at the front end of the conduit 2 via the traction devices 11, 11 of A and 12B.

Now, the elongated body traction device 11 of the present invention will be explained with reference to FIGS. A pair of guide shafts 17, 17 extending parallel to 2 are fixed.
A front moving frame 18 and a rear moving frame 19 are provided on the guide shafts 17, 17 so as to be movable in the direction of the arrow ROHA, and these front and rear moving frames 18, 19
A telescopic cylindrical net 20 through which the cable 7 is inserted is spanned between them. Also rear moving frame 1
A gripping cylinder mechanism 21 such as a hydraulic cylinder is fixed to the lower part of the cable 9, and its tip is connected to the front moving frame 18, so that the cable 7 can be gripped or released by expanding and contracting the net 20. It is being done. Furthermore, the support plate 16
A pair of traction cylinder mechanisms 22, 22 such as hydraulic cylinders are arranged parallel to the conduit 2 with an interval larger than the outer diameter of the cable 7 on both sides of the cable 7, and the tips of these traction cylinder mechanisms 22, 22 are It is connected to both sides of the rear moving frame 19. The traction cylinder mechanisms 22, 22 advance the net 20 when the net 20 is extended by the grip cylinder mechanism 21 and grips the cable 7, and move the net 20 forward when the net 20 is contracted and grips the cable 7. The net 20 is moved backward when the grip is released.

The support plate 16 has an insertion hole 16a for inserting the cable 7 at a position intersecting with the conduit 2 and engaging and disengaging the cable 7 upward. A halved cylindrical pipe receiver 16b is provided for positioning the traction device 11 with respect to the pipe 2 that has been opened.

Further, the net 20 is formed by forming a right-handed spiral and a left-handed spiral using wires, for example, and crossing these to form a cylindrical braided structure. Around the hole 18a and the cable insertion hole 19 of the rear moving frame 19
Each is held back around a. In its natural state, this net 20 has a constricted center shape, and in its stretched state, most of the inner diameter except for the vicinity of both ends is equal to or less than the outer diameter of the cable 7, and in its contracted state, its inner diameter is smaller than the outer diameter of the cable 7. The inner diameter is cable 7
It is made to be wider than the outer diameter of. This takes advantage of the fact that when a spiral is stretched in its axial direction, the spiral tends to become straight and its inner diameter tends to become extremely small.

Further, the gripping cylinder mechanism 21 has a drive shaft 2
1a is reciprocated in parallel with the pipe line 2 to move the rear moving frame 1.
The distance between the front moving frame 18 and the front moving frame 18 is adjusted, and the operation stroke is adjusted to the effective range of expansion and contraction of the net 20.
That is, the cable 7 can be gripped or released, and the traction cylinder mechanism 22 reciprocates its drive shaft 22a in parallel with the conduit 2 to close the support plate 1.
The rear moving frame 19 is moved toward and away from the rear moving frame 6, and its operation stroke is kept constant.

The chain line 23 indicates a chain for fixing the elongated traction device 11 to the manhole wall 3, and one end of the chain 23 is engaged with a fixing hook 24 provided on the traction cylinder mechanism 22. The other end is engaged with a book metal fitting (not shown) or the like that is driven into the manhole wall 3.

When pulling the cable 7 into the underground conduit 2 as shown in FIG. 2 using the elongated traction device 11 configured as described above, the pulling machine 15 is operated so that the tip of the cable 7 is pulled into the manhole. 12A, 12B
, and the pulling of the cable 7 by the pulling devices 11, 11 is started. That is, when the cable 7 is inserted into the net 20 when the net 20 is contracted and retracted as shown in FIG. 4a, the inner diameter of the net 20 is Stretch the cable 7 until it becomes equal to or less than the outer diameter of the cable 7. At this time, when the pulling force of the pulling machine 15 acts forward (in the direction of arrow D), the net 20 is dragged by the cable 7 and further stretched, so that the inner diameter of the net 20 is further pinched and the cable 7 is gripped more securely. In this state, as shown in Fig. 4C, the net 20 is advanced by a certain stroke to pull the cable 7, and then, as shown in Fig. 4D, the net 20 is moved forward until its inner diameter becomes larger than the outer diameter of the cable 7. Release the cable 7 by deflating it.
The cable 7 is pulled forward by repeating the operations shown in FIGS.
The installation work has been completed. However, in the above-mentioned laying work, both traction devices 11, 11 are operated synchronously.

According to this invention, a grip cylinder whose drive shaft is connected to the front movement frame is provided on the rear movement frame side, and a traction cylinder mechanism whose drive shaft is connected to the rear movement frame is provided on the wall side. Therefore, when the grip cylinder is extended and the long object is gripped by the net, the traction force of the winder is too strong compared to the traction force of the traction cylinder, and the long object is pulled forward. In the case of tension, the drive shaft of the gripping cylinder moves in the direction of extension, which makes the gripping of the elongated body by the net more reliable. Therefore, the fear of damage to the surface of the elongated object due to the slip phenomenon between the net and the elongated object is eliminated, and since the traction force of the traction device is reliably applied to the elongated object, the tension generated on the elongated object is ensured. Therefore, the installation work of the long body can be carried out more smoothly.

[Brief explanation of drawings]

Figures 1 a to d are explanatory diagrams of a conventional cable traction machine and its operation, Figures 2 to 4 show an embodiment of the present invention, and Figure 2 is a traction machine for a long body according to the present invention. An explanatory diagram of a method of laying a cable in a conduit by the device, Fig. 3a is a partially sectional plan view, Fig. 3b is a side view, and Figs. 4a to 4d are explanatory diagrams of operation. be. 2... Conduit, 3... Wall, 7... Cable (long body), 15... Pulling machine, 16... Support plate, 1
7...Guide shaft, 18...Front moving frame, 19...
Rear moving frame, 20... Net, 21... Gripping cylinder mechanism, 22... Traction cylinder mechanism.

Claims (1)

[Claims for Utility Model Registration] In an elongated object traction device for pulling an elongated object 7 along a conduit 2, a guide shaft parallel to the conduit is supported by a wall 3 or the like forming the conduit. 17, a front moving frame 18 and a rear moving frame 19 that are movably attached to the guide shaft, and a long body that is inserted between the front moving frame and the rear moving frame. A cylinder is fixed to the rear movable frame, and a drive shaft of the cylinder is fixed to the front movable frame, with the direction of expansion and contraction oriented along the guide shaft. a gripping cylinder mechanism 21 that grips the elongated body in the net when it is extended and releases the gripping state of the elongated body by the net when it is retracted; A traction device for an elongated body, comprising a traction cylinder mechanism 22 having a fixed driving shaft of a cylinder, the direction of which extends and contracts along the guide shaft, and which moves the rear movable body forward when it is extended. .