JPS608040A - Manufacture of thermo-shrinkable tube - Google Patents

Abstract

PURPOSE:To simply obtain a high-quality thermo-shrinkable tube suitable for connection of communication cable, etc., by a method in which a metal tape is wound around the periphery of a long material, and a thermo-shrinkable tape is further wound around the metal tape and integrated by heating into a tube form. CONSTITUTION:A metal tape 12 is cylindrically wound around the periphery of a long material, e.g., communication cable 1, etc., for example, and a thermo- shrinkable tape 14 is further wound around the metal tape 12 and uniformly heated until the interlayers of the thermo-shrinkable tape 14 are integrally bonded with each other. They are cooled, the metal tape 12 is shrunk beyond its original state to form an aperture between the tape 14 and the tube, and the metal tape 12 is removed out to obtain an aimed tube. EFFECT:Many kinds of thermo-shrinkable tubes can be simply produced in small numbers with excellent operability.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a heat shrinkable tube that fits on the outside of an elongate body.

This kind of heat-shrinkable tube that fits on the outside of an elongated body is used, for example, in the connecting part of a communication cable as shown in FIG.

In other words, 1.1 in Figure 1 is a communication cable, 1atl
a is the cable jacket, 2 is the core connection part between the communication cables 1.1, and the heat-shrinkable die 3.3 is connected to the communication cables 1.1, 4.4 and the main lead pipe 5 together with the auxiliary lead pipe 4.4 and the main lead pipe 5. It is fitted on the outside of 1. And heat shrink tube 3.
3 together with cable jacket 1 asla and heat shrink tube 3
．． 3, and its heat shrinkable tubes 3, 3 and auxiliary lead pipe 4.
By heating the hot-melt adhesive tape 6 wound so as to be located between the cable sheath 1a+1
a, the heat shrink tube 3.3 and the auxiliary lead pipe 4.4 are glued together. Further, the auxiliary lead pipe 4.4 and the main lead pipe 5 are joined to each other by a lead work part 7.

By the way, in the connection part of such a communication cable, for example, the existing communication cable 1 that is routed through a manhole
If it becomes necessary to provide such a connection in the middle of the
It is not possible to pass the cylindrical heat shrink tube 3, main lead pipe 5, and auxiliary lead pipe 4 through the existing communication cable 1 as in the normal case. Therefore, in such a case, the main lead pipe 5% auxiliary lead pipe 4 is first cut with a saw or the like, split vertically, and then fitted to the outside of the communication cable 1.
A vertical split connection method is used, in which each vertical split section is constructed with lead work at the top and then restored to its original cylindrical shape.

The heat shrink tube 3 also needs to be vertically divided once.

Therefore, as such a heat-shrinkable tube 3, a bonded heat-shrinkable sheet 8 as shown in FIGS. 2 and 3 has come to be used. The heat-shrinkable sheet 8 shown in FIG. 1 has both ends joined by zippers 9, and the heat-shrinkable sheet 8 shown in FIG. 3 has both ends joined by slit fittings 1o.

However, in such a bonded heat-shrinkable sheet 8,
Because the shape of the joint is complex, it is prone to deformation during shrinkage, variations in heating temperature, and incomplete adhesion of hot-melt adhesive, making it ideal for connecting communication cables that require complete airtightness and watertightness. There was a problem that it could not be applied.

On the other hand, instead of the heat shrink tube 30, there is a method of wrapping a heat shrink tape around the auxiliary lead pipe 4 and shrinking it by heating. However, in this method, the outer side of the heat-shrinkable tape wrapping layer shrinks first and its outer diameter is reduced during heating, so wrinkles occur in the inner layer and the layer between the heat-shrinkable tape layers or the heat-adhesive tape 6
There was a problem in that air bubbles were formed at the adhesive interface with the material, impairing airtightness and watertightness.

The present invention has been made in consideration of the above circumstances, and involves winding a metal tape in a cylindrical shape around the outside of a long object such as a communication cable, wrapping a heat shrink tape around the outer periphery of the metal tape, and then heating it. In particular, it is an object of the present invention to provide a method for producing a heat shrink tube that can easily and with high quality produce a heat shrink tube that fits on the outer circumference of a long body such as a communication cable. purpose.

Hereinafter, the present invention will be explained based on FIG. 9. FIG. 3 shows an example of manufacturing a heat-shrinkable tube to be used for a connection part of a communication cable 1 according to the present invention.

In producing the heat-shrinkable tube, first, a protective glass tape 11 is wrapped around the communication cable 1 to a thickness of about 100 ml, for example, to avoid thermal effects on the communication cable 1, and then, A metal tape 12 is wound around the local part with a sufficient gap to form a cylindrical shape. At this time, a heat-resistant tape such as an adhesive glass tape 13 is attached to the winding start part and the winding end part of the metal tape 12 to prevent the metal tape 12 from unraveling due to its own elasticity. Then, a heat-shrinkable tape 14 is wound around the circumferential surface of the metal tape 12 to a required thickness, and an adhesive glass tape 15 is applied to the end of the winding for temporary fixation. next,
A heating device such as a gasoline torch lamp, a propane torch, or an electric hot plaster is used to heat the heat-shrinkable tape 14 to a temperature (about
/3θ℃). At this time, the heat shrink tape 14 changes from a natural color (transparent white) to transparent. Therefore, the discoloration can be used as a judgment for heating control. After that, natural cooling or forced cooling by blowing air is performed, and when the heat shrink tape 14 (at this time it is a heat shrink tube) is hardened and cooled to a temperature that can be touched by hand, each adhesive glass Tape 15.
Remove 13.

Then, the metal tape 12 is narrowed so as to be wound smaller than the original state, a gap is formed between the metal tape 12 and the heat shrink tube formed by the heat shrink tape 14, and the metal tape 12 is pulled out. Next, when the glass tape 11 for heat insulation is removed, the process for manufacturing the heat shrink tube is completed.

As described above, according to the present invention, the heat-shrinkable tape 14 is tightly wound around the cylindrical winding frame of the metal tape 12, and the heat-shrinkable tape 14 is integrated, without having to be spliced in the circumferential direction. Moreover, a high-quality heat-shrinkable tube containing no air bubbles between the heat-shrinkable tapes 14 can be produced on the communication cable 1.

By the way, when wrapping the metal tape 12 to form a cylindrical shape,
The greater the elasticity and the thinner the material, the more beautiful the cylindrical shape will be.

On the other hand, the smaller the number of times the metal tape 1120 is wrapped, the easier the wrapping operation is, but the shrinkage force generated when the heated heat shrink tube cools and hardens makes the metal tape 1120 easier to wrap.
The metal tape 12 must be strong enough to prevent the metal tape 2 from being deformed. Therefore, the material, thickness, and number of turns of the metal tape 12 are determined in consideration of the above points. For example, when producing a heat-shrinkable tube with an inner diameter of θ~gOtmn and a thickness of 2~3ttan using a crosslinked polyethylene tape as a material, a stainless steel plate for a spring material with a thickness of θ/- is used as the metal tape 12, 3~
It is best to wrap it three times. In addition, as a result of producing a heat-shrinkable tube under such conditions, the time required for the work was extremely short and efficient, i.e., j minutes to /θ minutes, including the natural cooling time. Furthermore, the finished product had almost no bubbles and could be sufficiently applied as a heat-shrinkable tube for connecting the communication cable 1.

As explained above, according to the heat-shrinkable tube manufacturing method according to the present invention, the heat-shrinkable tape is wrapped along the outer periphery of a long body such as a communication cable using metal tape, and
Then, by integrating the heat-shrinkable tape into a tube shape using heat, a heat-shrinkable tube that fits on the outside of the elongated object is manufactured. Heat shrinkable tubes can be easily produced with good workability and high quality. Furthermore, this method is most suitable as a method for easily producing high-quality heat-shrinkable tubes in small quantities.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a connection part of a communication cable using a heat-shrinkable tube and a hot-melt adhesive, Figs. 1 and 3 are cross-sectional views showing different examples of bonded shrink sheets, and Fig. 9 is a cross-sectional view of the invention. It is a conceptual diagram shown in order to explain the implementation situation. 1...Communication cable, 3...Heat shrink tube, 12...Metal tape, 14...
heat shrink tape. Applicant: Nippon Telegraph & Co., Ltd.

Claims (1)

[Claims] A method for manufacturing a heat-shrinkable tube that fits on the outside of a long body, in which a metal tape is wound around the outside of the long body in a cylindrical shape, the heat-shrinkable tape is wrapped around the outer circumferential surface of the tube, and then the heat-shrinkable tube is heated. A heat shrink tube, characterized in that the heat shrink tube is produced by heating the shrink tape until it becomes integrated as a heat shrink tube, then allowing the integrated heat shrink tube to cool, and then removing the metal tape. Fabrication method.