JPS6241464B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-shrinkable member used for connecting cables and the like.

Recently, heat-shrinkable sleeves have been widely used for connecting cables, etc., and their structure is as follows:
Consists of an outer layer made of heat-shrinkable plastic such as cross-linked polyethylene and an inner layer made of heat-fusible or adhesive material such as ordinary polyethylene or ethylene-vinyl acetate copolymer, and each layer is smooth and has a constant thickness. It was hot.

When connecting cables, etc. in a straight line, if you make a heat-shrinkable member as a circular tube-shaped sleeve and apply it, no particular problem will occur, but when connecting branch cables, etc., such conventional heat-shrinkable material Problems remain with sexual parts. That is, as shown in FIG. 1(a), both the outer layer 1a made of heat-shrinkable plastic and the heat-fusible or adhesive inner layer 1b are made of a heat-shrinkable sheet 1 having a constant thickness, and as shown in FIG. 1(b), for example, the main cable 3 with ₁ C 1 and 2 branch cables C ₂ and C ₃
When forming branches, cover them with a heat-shrinkable sheet 1 as shown in FIG. As shown in Fig. 1C, heat is applied from the outer periphery of the heat-shrinkable sheet 1 to heat-shrink it onto the cable, and the gap between the cables is pressed in the direction of the arrow with a tool to tightly join them and form a narrow part. 2 to complete a completely sealed branch connection as shown in FIG.

FIG. 2 shows two branch cables C ₂ and C ₃ covered with a circular heat-shrinkable sleeve 1, and the gap 3 between the branch cables has a spring action having a narrow part 4 and a grip part 5. The branch connection is crimped with a tool 6, forming a constricted portion, and completely hermetically covering the branch connection.

Note that instead of the tool 6 mentioned above, a U-shaped jig 7 as shown in Fig. 3A is used to connect the branch cable.
Fit the ends of the heat-shrinkable sleeve 1 above the gap between C ₂ and C ₃ and connect the end of the heat-shrinkable sleeve 1 to the parallel part 7
A and 7b are pressed to seal tightly as shown in FIG. 3B.

In the above, the heat-shrinkable sleeve 1 naturally consists of a heat-shrinkable outer layer 1a and a heat-shrinkable or fusible inner layer 1b, as shown in FIG. 1A.

Now, in this method of connecting cable jackets using heat-shrinkable materials, the heat-shrinkable material cannot be made very thick, so the mechanical strength, especially the tensile strength, is not suitable for the lead pipe construction method or mechanical assembly method. It has the disadvantage of being relatively weak. We would like to compensate for this drawback by increasing the thickness as much as possible, but in reality, the outer layer of cross-linked stretched plastic has a thickness of 0.5 to 1.0 mm, or the adhesive inner layer has a thickness of 0.5 mm.
~1.5 mm, with a total thickness of 1.5 to 2.5 mm or less, are commercially available as cable jacket connection sleeves, and thicker sleeves increase the rigidity of the sleeve and reduce the gap between cables when connecting cable branches. That is, at present, this has not been realized because it is difficult to process the troughs to constrict them and bring them into close contact.

However, in a heat-shrinkable member consisting of a heat-shrinkable plastic outer layer 1a and a heat-fusible or adhesive plastic inner layer 1b, the present inventors added a shrinkable member to one or both of the outer layer 1a and inner layer 1b. By providing longitudinal corrugation in some or all of the necessary locations of the shrinkable member, the above-mentioned drawbacks can be solved, and a heat-shrinkable member with a thicker thickness can be created, which means that the heat-shrinkable member has a large strength. This makes it possible to provide a contractible member.

Next, examples of the present invention will be described.

FIG. 4A shows an example of the heat-shrinkable member of the present invention, and shows a longitudinal section in FIG.
As shown in ], the heat-shrinkable member is a cylindrical sleeve 1 consisting of a heat-shrinkable plastic sleeve 1a and a heat-sealable or adhesive inner layer 1b. It has a tubular shape, and the inner layer has a smooth central portion, that is, a portion that covers the core wire connection portion, and the outer sheath connection portions at both ends are corrugated 1b-w in the longitudinal direction.

FIG. 5 is a side view showing a state in which branch cables are connected using another example of the heat-shrinkable member of the present invention, and the cables C ₂ and C ₃ are covered with the heat-shrinkable sleeve 1 according to the present invention. This heat-shrinkable sleeve 1 has corrugations 1 in the axial direction at least at the ends of the inner layer 1b of the heat-shrinkable sleeve 1 at positions corresponding to the valleys between the cables.
Using a material marked with b-w, heat shrink the corrugated part 1b-w, and use a tool to crimp and constrict the corrugated parts to join. Needless to say, the position of the corrugation is designed in advance based on the cable size and arrangement. Furthermore, the structure of the corrugated portion of the heat-shrinkable member of the present invention is as shown in FIG. The inner layer 1b is flat, and the heat-shrinkable outer layer 1a is flat as shown in (b).
One in which axial corrugations 1b-w are attached only to the heat-fusible or adhesive inner layer 1b, and one in which corrugations 1a-w and 1b-w are attached to both the heat-shrinkable outer layer 1a and the heat-shrinkable inner layer 1b, respectively, as shown in c. The following may be considered.

The heat-shrinkable member according to the present invention has a sheet-like or sleeve-like structure, and when used for non-linear connections such as branch cables, the above-mentioned axial waveform acts effectively. (1) Branching of cables When performing connection work, it is extremely easy to use a jig to narrow the gap between the cables from the outside of the heat-shrinkable material, form a constriction, and make them fit tightly together. (3) By increasing the thickness of the heat-shrinkable material, the strength increases; (4) When the inner layer is corrugated, the inner layer is partially Since it is possible to increase the adhesion volume of the material and increase the apparent shrinkage rate, it is possible to widen the range of cable diameters to which one heat-shrinkable member can be applied.

It is possible to achieve various effects such as.

[Brief explanation of the drawing]

Figure 1 A is a cross-sectional view of a conventional heat-shrinkable member, Ro to Ni are cross-sectional views showing changes in the state in which this heat-shrinkable member is used for cable branches, and Figure 2 is a cross-sectional view of a conventional heat-shrinkable member. A perspective view showing a situation in which the gap between cables is crimped and brought into close contact with a member covering jig, Figure 3A is a perspective view of a U-shaped jig used to crimp the gap between cables and bring them into close contact; 4 shows an example of the heat-shrinkable member according to the present invention, and FIG. 4 shows an example of the heat-shrinkable member according to the present invention. A vertical cross-sectional view when a corrugated portion is provided, B is a cross-sectional view taken along line XX of A, FIG. 5 is a cross-sectional view when the heat-shrinkable member of the present invention is used for two branch cables, and FIG. 6 is a cross-sectional view of the present invention. A is a cross-sectional view showing the structure of a heat-shrinkable member. A is a case where a corrugated part is provided on the heat-shrinkable outer layer, B is a case where a corrugated part is provided on a heat-fusible or heat-adhesive inner layer, and C is a case where a corrugated part is provided on the heat-sealable or heat-adhesive inner layer. This shows the case where corrugated portions are provided on both layers. C ₁ ... Main cable, C ₂ , C ₃ ... Branch cable, 1 ... Heat-shrinkable sheet, sleeve, 1a ...
Heat-shrinkable outer layer, 1b... heat-shrinkable inner layer, 2... constriction, 3... gap between branch cables, 6...
Tool with spring action, 7... U-shaped jig, 1
a-w...corrugation of the outer layer, 1b-w...corrugation of the inner layer.

Claims (1)

[Scope of Claims] 1. In a heat-shrinkable member consisting of an outer layer of heat-shrinkable plastic and an inner layer of heat-fusible or adhesive plastic, at least part or all of the outer layer or the inner layer contains the shrinkable member. A heat-shrinkable member characterized by being corrugated in the length direction. 2. The heat-shrinkable member is cylindrical, and the heat-sealable or adhesive plastic inner layer at the end thereof is corrugated in the length direction of the shrinkable member. Heat-shrinkable material. 3. In a heat-shrinkable member in which a constriction is formed according to the shape of the article to be wrapped, at least the outer layer or inner layer of the heat-shrinkable member is corrugated in the length direction at a position corresponding to the constriction. A heat-shrinkable member according to claim 1. 4. The heat-shrinkable member according to claim 1, wherein the shrinkable member is a tubular body. 5. The heat-shrinkable member according to claim 1, wherein the shrinkable member is a sheet.