JPS6048428B2 - cable towing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cable traction machine for towing cables such as communication cables when installing or removing them.

Conventionally, as shown in FIG. 1, this type of cable traction machine has one hydraulic cylinder 2 attached to the machine frame 1, and a moving base 4 attached to the tip of the rod 3. The hydraulic cylinder 5 is installed in the opposite direction to the hydraulic cylinder 2, and the machine frame 1 is attached to the tip of the rod 6.
Attach a second moving platform 8 equipped with rollers 7 that roll on top,
Further, support rings 11, 11 provided at both ends of a net 10 formed in a cylindrical shape so as to surround the cable 9 are attached to each of the movable tables 4, 8, and the rod 6 of the second hydraulic cylinder 5 is By stretching the net 10, the cable 9 is gripped by the net 10, and in this state, the machine frame 1 is
The cable 9 is pulled by extending the rod 3 of the hydraulic cylinder 2 attached to the second hydraulic cylinder 2, and then the rod 6 of the second hydraulic cylinder 5 is retracted to loosen the net 10 to release the grip on the cable 9 and the hydraulic cylinder 2 A device is known in which the net 10 is returned to its original position by contracting the rod 3, and the cable 9 is intermittently pulled by repeating the above operation.

According to such a device, each operation of gripping, pulling, releasing the grip, and returning the cable can be performed automatically, so that cable installation and removal work can be carried out efficiently, and the net 10 Since the cable 9 is gripped by the cable 9, the cable 9 can be prevented from being cut and the insulation coating can be prevented from being damaged. However, in the conventional device described above, the cable 9 is towed by one hydraulic cylinder 2, and since the hydraulic cylinder 2 and the cable 9 are separated by a predetermined distance l, the cable 9 is towed. At this time, a bending moment acts on the rod 3 of the hydraulic cylinder 2, and the bending moment is caused by the fact that the cable 9 itself is heavy and the frictional force between the cable 9 and the inner surface of the tunnel is considerable. Due to the considerably large output, a considerably large bending moment is generated, and as a result, the rod 3 of the hydraulic cylinder 2 may be slightly bent due to the bending moment caused by towing, and the sealing material installed inside the cylinder may be damaged. There was a problem that could easily occur. Furthermore, in the conventional device described above, the second movable table 8 is guided by rollers 7 attached to the movable table 8, but the towing stroke by the above device is quite short compared to the cable length. Therefore, for example, when the cable 9 is completely pulled out from the tunnel, the number of repetitions of the above-mentioned operation becomes considerably large, and the number of rotations of the roller 7 increases accordingly, causing the roller 7 itself to wear out prematurely. There was a problem that the bearings could be damaged prematurely. The object of the present invention is to provide a cable traction machine that can effectively solve the above problems.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 6. FIG. 2 is a plan view showing one embodiment of the present invention, and FIG. 3 is a side view thereof, showing the machine frame 20. A pair of mounting plates 21 having recesses 21a through which a cable is inserted are provided at both front and rear ends of the main hydraulic cylinder 22, and a pair of main hydraulic cylinders 22 are mounted at symmetrical positions between these mounting plates 21. .

．． These main hydraulic cylinders 22 are both single-acting type or double-acting type, and are configured so that each rod 22a moves forward and backward at the same time by supplying pressure oil and removing pressure oil. A moving block 23 is fixed to the tip of the rod 22a. This moving block 2
3, as shown in FIG. 4, a main body 23a in which a U-shaped recess is formed, and an opening/closing piece 23b rotatably attached to one side of the upper end of the main body 23a so as to close the recess. The center axis of the circular opening formed by the main body part 23a and the opening/closing piece 23b is formed so as to pass through the center between each of the main hydraulic cylinders 22, and there is a gap between the main body part 23a and the opening/closing piece 23b. A support ring 25 provided at one end of the net 24, which will be described later.
a and lock the opening/closing piece 23b with the lock screw 26.
The support ring 25a is fixed to the moving block 23 by being fixed to the main body part 23a at. The main hydraulic cylinder 2 is located at the lower center of the moving block 23.
An auxiliary hydraulic cylinder 27 is installed parallel to the main hydraulic cylinder 22 and in the opposite direction to the main hydraulic cylinder 22, and a pair of guide rods are provided on both the left and right sides of the rod 27a of the auxiliary hydraulic cylinder 27 at the lower part between the machine frames 21. 28 is provided, and a second moving block 29 fixed to the tip of the rod 27a of the auxiliary hydraulic cylinder 27 is provided so as to be slidably engaged with the guide rod 28. This second moving block 2
Reference numeral 9 is arranged parallel to the moving block 23 attached to the rod 22a of the main hydraulic cylinder 22, and has a recess formed in the main body of the moving block 23 and a recess having approximately the same shape as the guide. A main body 29a that engages with the rod 28, and an opening/closing piece 2 rotatably attached to one side of the upper end of the main body 29a to close the recess of the main body 29a.
9b, the central axis of the circular opening formed by the main body 29a and the opening/closing piece 29b coincides with the central axis of the circular opening in the moving block 23, and between the main body 29a and the opening/closing piece 29b. By sandwiching the support ring 25b provided at the other end of the net 24 and fixing the opening/closing piece 29b to the main body part 29a with the lock screw 30, the support ring 2
5b is fixed to the moving block 29. Here, to explain net 24, net 2
4, wire rods 24a having a relatively high tensile strength, such as steel wire or stainless steel wire, are arranged in a tube so that the wire rods 24a can surround the cable and each wire rod 24a runs diagonally with respect to the axial direction of the cable. It is braided into a shape, and further has support rings 25a, 25b provided at both ends, and each support ring 25a
, 25b are spaced apart and extended to reduce the diameter and grip the cable, and conversely, each support ring 25a, 25b
By bringing the cables closer together and shortening them, the diameter expands and the grip on the cable is released. In addition, 25a in the figure
' is a guide collar to prevent and guide the cable from sudden bending. Of the mounting plate 21 of the machine frame 20, hooks 31 are attached to a total of four locations: the upper left and right sides and the lower left and right sides of the mounting plate 21 on the tip side (right side in FIGS. 2 and 3). In addition, a duct receiver 32 for inserting and positioning the cable into the tunnel is protruded from the mounting plate 21 on the rear end side, and with the duct receiver 32 inserted into the tunnel, the machine frame 20 can be The machine frame 20 or The towing machine having the above structure is configured to be fixed to the wall surface of the opening end of the tunnel.

In the figure, numeral 33 is a limit switch that issues a signal for automatic operation, and numeral 34 is a boat to which a hydraulic hose (not shown) is connected.

Next, the operation will be explained with reference to FIGS. 6A to 6D.

Note that FIGS. 6A to 6D are schematic diagrams for explaining the operation, and unnecessary parts are omitted and the position of the auxiliary hydraulic cylinder 27 is omitted. First, as shown in FIG. 6A, the cable traction machine having the above-described structure is fixed perpendicularly to the wall surface 36 of the opening end of the tunnel 35, and the cable 37 is inserted through the net 24 and each support ring 25a, 25b.
After completing the above preparatory work, as shown in FIG. Reduce. let me cable 37
to grasp. Next, as shown in FIG. 6C, if pressure oil is supplied to each main hydraulic cylinder 22 to move its rod 22a forward, the net 24 holding the cable 37 will move forward together with the moving block 23. Cable 37 is broken. The main hydraulic cylinder 22 is pulled out from the tunnel 35 by the stroke of the main hydraulic cylinder 22 . In this case, each main hydraulic cylinder 2
2 are placed in symmetrical positions with respect to the cable 37, so when each rod 22a is moved forward, no bending moment is applied to each rod 22a.
Therefore, as the traction load of the cable 37 is shared by each main hydraulic cylinder 22, the load applied to each rod 22a is small, and the rod 22a is bent and the sealing material provided in the cylinder is damaged. It will never occur. After pulling out the cable 37 as described above,
If the auxiliary hydraulic cylinder 27 is returned to its original position as shown in FIG.
25b relatively approaches, the net 24 relaxes, and as a result, the diameter of the net 24 expands, and the grip of the cable 37 by the net 24 is released. Thereafter, by returning each main hydraulic cylinder 22, the movable blocks 23, 29, net 24, etc. return to their original positions shown in FIG. It was pulled out from the tunnel 35. In addition,
While performing the above-mentioned operation, the auxiliary hydraulic cylinder 27
A moving block 29 attached to the tip of the rod 27a repeatedly moves back and forth, but this moving block 29 is configured to move while being guided by a guide rod 28, and unlike conventional cable traction devices, it uses rollers. Because it is not a mechanical device, there are fewer parts that are easily worn out or damaged, such as rollers and their bearings, and it can be used continuously for a long period of time without failure. In addition, in the above embodiment, the pair of main hydraulic cylinders 22 are arranged at symmetrical positions on the left and right sides of the cable 37 to be towed, but in this invention, the pair of main hydraulic cylinders are arranged at symmetrical positions on the upper and lower sides of the cable. Alternatively, the sub hydraulic cylinder 27 may have one
It does not have to be a book, and it may be configured such that a pair of auxiliary hydraulic cylinders are arranged symmetrically with respect to the cable to be towed. As explained above, according to the cable traction machine of the present invention, the pair of main hydraulic cylinders for towing the cable are arranged at symmetrical positions with respect to the cable. When the cable is towed, no bending moment is applied to the rods of each main hydraulic cylinder, thus preventing malfunctions of the main hydraulic cylinders due to bending of each rod or damage to the sealing material in the cylinders. In addition, since the movable block attached to the end of the rod of the auxiliary hydraulic cylinder is guided by the guide head throat, it can be used for a long period of time since there are no parts that are easily worn or damaged, such as rollers and their bearings in conventional equipment. Therefore, according to the present invention, it is possible to obtain a cable traction machine that is easy to maintain and manage.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a conventional cable traction machine, Fig. 2 is a plan view showing an embodiment of the present invention, Fig. 3 is a side view thereof, and Fig. 4 is a front view showing one of the moving blocks. , FIG. 5 is a side view showing the net, and FIGS. 6A to 6D are schematic diagrams for explaining the operation.

Claims (1)

[Scope of Claims] 1. A pair of main hydraulic cylinders are installed along the cable to be towed and at symmetrical positions about the cable on the machine frame, and a moving block is installed at the rod end of each main hydraulic cylinder. A sub-hydraulic cylinder is attached to the movable block along the direction in which the cable is pulled out, and a second movable block is attached to the rod end of the sub-hydraulic cylinder parallel to the movable block, and the cable is connected to the machine frame. Each support ring is slidably engaged with a guide rod provided along the pulling direction of the cable and is attached to both ends of a cylindrical net so as to surround the cable, and is detachably attached to each of the moving blocks. A cable traction machine characterized by being attached to. 2. A hook is provided at the tip of the machine frame to engage a chain in order to fix the machine frame by bringing the rear end of the machine frame into contact with the wall surface of the opening end of the cable tunnel. A cable traction machine according to claim 1.