JPS5912467Y2 - Connection sleeve of different synthetic resin tubular bodies - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a connecting sleeve used to connect different composite or resin tubular bodies, such as a polyethylene tubular body and a polyvinyl chloride tubular body.

For example, when connecting tubular bodies such as cable sheaths or plastic pipes, a connecting sleeve as shown in Fig. 1 has conventionally been known only when the tubular bodies to be connected are made of the same plastic resin material. be.

That is, in the same figure, when connecting tubular bodies made of the same type of composite resin material, for example cable sheaths IA and 1B, the connecting sleeve 4, which has been fitted in advance over the conductor connecting part 3, is moved and both ends thereof are heated. te code 4. As shown in a, a step is taken to shrink and fuse both cable sheaths 1A and IB to be connected.

This connection sleeve 4 is connected to the cable sheath IA to be connected,
It is shaped by stretching the same type of composite resin material as 1B, which is why it has heat shrinkability and good heat fusion properties with cable sheaths IA and IB. This is because an airtight connection is possible as shown in the figure.

However, when connecting resin pipes made of different materials, for example, tubular bodies made of different resins such as polyvinyl chloride and polyethylene, as in the case of overhead cables and underground cables, 1
The connecting sleeve 4 shown in the figure cannot be used.

This is because the connecting sleeve is made of the same material as either one of the tubular bodies to be connected, and therefore there is complete heat fusion between the ends of the connecting sleeve and the same type of resin. However, sufficient thermal fusion cannot be expected between different resins.

This is because, for example, in the case of the above-mentioned materials, polyvinyl chloride is a polar polymer, whereas polyethylene is a non-polar polymer, and there is no affinity or compatibility between the two. .

In fact, there are many cases in which tubular bodies made of different resin materials are connected, and there has been a strong desire to develop a connecting sleeve for use in such cases.

An object of the present invention is to provide a connecting sleeve for composite resin tubular bodies that can connect composite resin tubular bodies made of different materials.

In order to achieve this purpose, the present invention has a heat-shrinkable layer made of a thermoplastic resin which has a hollow columnar shape as a whole and is stretched to shrink in the radial direction, and a heat-shrinkable layer inside the heat-shrinkable layer in the axial direction. A heat-sealing layer made of a different thermoplastic resin is provided on the left side and the right side, respectively.

An embodiment of the present invention will be described in detail with reference to the drawings.

In FIG. 2, reference numeral 5 designates a heat-shrinkable layer made of a thermoplastic resin such as polyethylene, which has a hollow columnar shape and is stretch-crosslinked so as to shrink in the radial direction.

Inside this heat-shrinkable layer 5, a fusion layer 6 made of the same material as the resin material of one of the tubular bodies to be connected, for example, polyethylene, is provided over approximately half the length in the vertical direction.
A fusion layer 7 made of the same material as the other tubular body to be connected, for example polyvinyl chloride, is provided over the remaining half length.

The connecting sleeve of this invention can be made, for example, by the method shown in FIG.

That is, an uncrosslinked polyethylene tape and a polyvinyl chloride tape are wound on a columnar, usually cylindrical mandrel 8 over approximately the same length in the axial direction to form a laminated layer 6'.
and 7'.

Next, a heat-shrinkable layer 5 is provided on top of these, in which a cross-linked polyethylene tape is wound in a stretched state.

Thereafter, for example, the core metal 8 is inductively heated by an induction coil 9 to thermally crosslink the uncrosslinked polyethylene tape wound laminate 6' to form the polyethylene fusion layer 6, and the polyvinyl chloride tape wound laminate 7' is formed by fusion. The polyvinyl chloride fusion layer 7 is formed by attaching the polyvinyl chloride adhesive layer 7, which is then integrated with the heat shrinkable layer 5 on the outside thereof, and then cooled and extracted from the core bar 8.

In this case, it is even more reliable if a suitable adhesive or chlorinated polyethylene is interposed between the polyvinyl chloride tape wound layer 7' and the crosslinked polyethylene tape wound layer 5 to ensure complete adhesion.

The function of connecting tubular bodies made of different resin materials, such as cable sheaths 1 and 2, by the connecting sleeve of this invention will be explained in the third section.

That is, the connection sleeve is inserted so that the material of the heat-sealing layer of the connection sleeve matches the respective tubular bodies.

For example, if the material of the tubular body 1 is polyethylene and the material of the tubular body 2 is vinyl chloride, a heat-sealing layer 6 of polyethylene is placed on the side of the tubular body 1 as shown in the figure.

After such preparation, by heating both ends of the connection sleeve, the heat-sealing layers 6 and 7 are fused and integrated with the tubular bodies 1 and 2 made of the same material as themselves, respectively, as shown by reference numerals 5a and 7a. Further, the heat-shrinkable layer 5 thereon is shrunk to cover each fused portion as shown by reference numeral 5a, and thus the tubular body 1
and 2 are completely airtightly connected by means of this connecting sleeve, and at the same time mechanical strength is guaranteed.

As detailed above, according to this invention, (1) When the resin materials of the tubular bodies to be connected are different from each other, a fusion layer is provided that facilitates heat-sealing to the material of each tubular body. (11) Since a heat shrink layer is provided above each welding layer, the welded parts at both ends of the connection sleeve are covered, and the connection part is completely sealed. It has the advantage of ensuring mechanical strength, and particularly when applied to cable sheaths, it has the advantage of ensuring reliable interconnection between overhead cables and underground cables that are usually made of different materials.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing a prior art connecting sleeve;
Figure 3 is a side sectional view showing an embodiment of this invention, Figure 3 is a side sectional view showing a connection state using the connecting sleeve of this invention, and Figure 4 is a side sectional view illustrating an example of the method for manufacturing the connecting sleeve of this invention. FIG. 1, 2... Tubular body, 5... Heat shrink layer, 6, 7...
Fusion layer.

Claims (1)

[Scope of utility model registration request] The heat shrink layer 5 has a hollow columnar shape as a whole and is made of a thermoplastic resin that has been stretched to shrink in the radial direction. Thermal adhesive layers 6 and 7 made of plastic resin
and the materials of these heat-sealing layers 6 and 7 are made of different resins, characterized in that they have affinity and compatibility with the materials of the resin tubular bodies connected to each other. Connecting sleeve of tubular body.