JPS6026241B2 - Spiral tube for protecting flexible electric wires and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a helical tube for protecting flexible natural wires such as telephone cords and communication terminal cords.

Cords for telephones and communication devices such as those listed above are
Unlike ordinary electric wires and cables, they are short in length and must withstand harsh usage conditions such as twisting, bending, and impact.

In addition, it is necessary to prevent public telephone cords from being tampered with or stolen, so records are inserted into metal spiral tubes that are flexible against bending. As shown in Fig. 1, the spiral tube used here is made by bending a band-shaped metal body into a horizontal S-shape 1 in cross section, and the adjacent folded ends 12 are engaged with each other to create a flexible structure. It is flexible against bending and strong against tension as the bent parts engage with each other, but if a strong force is applied in the direction of twisting the spiral pipe, In some cases, this may become deformed and the bent and joined part may come off, or
There were many accidents in which the metal band in this area broke and the spiral tube was damaged. The present invention aims to eliminate such drawbacks, and this will be explained with reference to FIG. 1. 1 is a conventionally used spiral tube as described above, and 2 is an elastic band made of elastic metal. , which is spirally wound in the opposite direction to the winding direction of the spiral tube 1 and inserted so that it comes into close contact with the inner surface of the spiral tube 1, and 3 is the width of this interval.

Reference numeral 4 denotes the ends of these, and with the spiral tube 1 of a certain length stretched, the end of the internal elastic band 2 and the end of the spiral tube 1 are welded, brazed, soldered, or any other suitable method. It is welded together.

Reference numeral 5 denotes flexible electric wires inserted inside, and a gap is provided between them and the elastic band 2 to allow movement of the flexible electric wires. Since the present invention has the above-described structure, when the spiral tube 1 is twisted in the same direction as the winding direction, the diameter of the spiral tube 1 becomes small, but the internal elastic band 2 is connected to the spiral tube 1 and both ends 4. Because they are welded, they twist in the same direction, but since this is the opposite of the spiral tube 1, their diameter increases and they press against each other,
This provides resistance to twisting and prevents deformation of the spiral tube 1.

Next, when the spiral tube 1 is twisted in the opposite direction to its winding direction, the twist of the spiral tube 1 becomes large, but the elastic band 2 inside is twisted in the same direction as the winding direction. The diameter is 4 mm, and since it is in close contact with the flexible electric wires 5 inserted into the elastic band 2, it provides resistance to twisting and prevents the helical tube 1 from deforming.

The above action is achieved by inserting the elastic band 2 inside the spiral tube 1 while it is stretched, and by welding both ends of the tube, it can withstand any twisting or bending and completely protect the electric wires inside. Is possible. Note that the spiral tube 1 works effectively as before to prevent impact and theft. In addition, in the above structure, elastic bands 2 with opposite winding directions are used as the elastic bands 2.
It will be more effective if the two or three sheets can be stably inserted into the spiral tube 1.

Note that the same effect can be obtained even if a linear elastic spiral body is used instead of the elastic band 2.

As described above, the spiral tube 1 of the present invention is constructed by bending a metal strip into a horizontal S-shaped cross section and interlocking the adjacent ends thereof, so it is not necessary to manufacture the spiral tube 1 in a hollow shape. Therefore, it is impossible to construct the helical tube 1 by winding a band-shaped metal plate on the helically wound elastic band 2. Therefore, it is necessary to cut the completed spiral tube 1 to a certain length and insert the spiral elastic band 2 inside this, but this needs to be tightly attached to the inner surface of the spiral tube 1, and this manufacturing process is extremely difficult. Have difficulty.

Next, a method for manufacturing a helical tube for protecting a flexible electric wire according to the present invention, which solves the above-mentioned manufacturing problems, will be explained in the order of steps with reference to FIGS. 2 to 4.

A. Cut the spiral tube 1 into a length determined by the purpose of use, and fix it in the stretched state with a fixing odor.

(See Fig. 2) The fixed odor 6 is fixed by passing a fixing rod 63 through a fixing plate 6 having a notch 62 for fitting it into the concave part 13 of the spiral tube 1 and tightening it with an adjusting screw 64, as shown in Fig. 2, for example. The length is adjusted and fixed.

B. Prepare a winding rod 7 that is larger in length than the spiral tube 1 in A above and narrower than the inner diameter of the spiral tube 1. As shown in Fig. 3, this winding is provided with a step 7 at one end, and
On the opposite side, a protrusion 72 having a thickness corresponding to the interval width 3 of the elastic band 2 shown in FIG. It is supposed to be done. Further, 9 is a winding frame around which the elastic band 2 is wound. One end of this elastic band is temporarily fixed to the bookkeeper with the stepped portion 7 of the winding rod, and after wrapping it around both sides of the protrusion 72, the winding rod 7 is rotated. Then close-wrap it to a certain length. C Next, inside the spiral tube 1 stretched and fixed on the fixed odor 6 prepared in A above,
Insert the winding rod 7 on which the elastic band 2 prepared in B above is tightly wound.

D In this state, when the temporary fixation at the stepped portion 7 of the winding rod 7 is removed, the elastic band 2 is opened inside the spiral tube 1, and the end of the elastic band 2 is pushed inside the spiral tube 1 due to its elasticity. Close to.

At this time, the spiral tube 1 and the elastic band 2 are fixed so as not to rotate. Therefore, when only the winding rod 7 is rotated in the opposite direction to the winding direction of the elastic band 2 and moved to the right as shown in FIG. 72 competes by the width of the protrusion 72,
The elastic bands 2 are successively brought into close contact with the inner surface of the helical tube 1 while maintaining a gap width of 3. In this way, the winding rod 7 is removed from the inside of the spiral tube 1. E By the above D, the red length of the elastic band 2 that is uniformly opened over the entire length of the spiral tube 1 and in close contact with the inner surface of the tube is cut, and this is removed from the winding 7.F Next, the ends of the spiral tube and the elastic band 2 are cut. After aligning these and welding them by an appropriate method such as welding, brazing, or soldering, the fixture 6 attached at A is removed to release the spiral tube 1 from its stretched state, and the manufacturing is completed.

In the protective helical tube of the present invention manufactured by the above steps, the elastic band 2 is wound in the opposite direction to the winding direction of the helical tube at equal intervals over almost the entire length inside the helical tube 1, and the Since the structure is such that the flexible wire passes through the helical tube, even if a force that bends the helical tube is applied from the outside, the elastic force of the elastic band 2 acts in a direction to prevent the helical tube from deforming. The flexibility of the tube as a whole is maintained, and the electric wires passing through the center can be sufficiently protected.

In addition, since the end of the elastic band 2 is fixed to the end of the helical tube 1, the restoring force of the elastic band 2 keeps the elastic band 2 and the helical tube 1 in close contact with each other, and the tube does not twist or form a dumpling. The tube does not get tangled and maintains its uniformity.

[Brief explanation of drawings]

FIG. 1 is a partial vertical sectional view of the spiral tube of the present invention, and FIGS.
The figure is an explanatory diagram of the method for manufacturing a spiral tube of the present invention. 1...Spiral tube, 2...Elastic band, 3...
...Gap width, 4...End, 5...Electric wires,
6...Fixed odor, 7...Rolling rod, 8...
... Chuck, 9 ... Elastic band reel. Figure 2 Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1. A metal spiral tube formed by spirally winding the widthwise ends of a band-shaped metal body so as to interlock with each other, and a metal spiral tube that closely penetrates the inside of this metal spiral tube. A metal elastic band spirally wound in a direction opposite to the winding direction of the metal spiral tube, and a fixing part that fixes both ends of the metal elastic band to both ends of the metal spiral tube, respectively. A spiral tube for protecting flexible electric wires. 2 A Process of fixing in a stretched state a metal spiral tube of a certain length, which is formed by spirally winding the widthwise ends of the band-shaped metal body so as to interlock with each other; B having a protrusion at one end; After temporarily fixing one end of a metal elastic band to a winding rod that is thinner than the inner diameter of the metal spiral tube, the elastic band is spirally wound around the winding rod in a direction opposite to the winding direction of the metal spiral tube. Step C of tightly winding; Step D of inserting the wound rod tightly wound with the elastic band in step B into the spiral tube stretched in step A;
Remove the temporary fixing in the step B, release the elastic band inside the spiral tube, bring the elastic band into close contact with the inner surface of the spiral tube, and rotate only the winding rod in the opposite direction to the winding direction of the elastic band. Removal step E Step F of cutting the extra length of the elastic band opened inside the helical tube in step D Align the ends of the helical tube and elastic band obtained in step E, and attach elastic bands to both ends of the helical tube The process of fixing both ends of the helical tube and releasing the stretched state of the spiral tube performed in the above process A.
, C, D, E, and F. A method for manufacturing a spiral tube for protecting flexible electric wires.