JP2003097784A - Fusion joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fusion joint not requiring to cut fusion connection surface of connecting part of a thermoplastic resin pipe to be connected or a thermoplastic resin joint and allowing to easily confirm if a necessary fusion length is inserted in a socket of the joint. SOLUTION: A disk shaped rib 13 is projectingly provided on outside of roughly center part of a short tubular thermoplastic resin main body 12. The main bodies 12 in both sides of the rib 13 are defined as spigots 121, 122. Electric heat wire 14 to generate heat by being energized is embedded in adjacent of outer circumference surfaces of both spigots 121, 122. A lead terminal 15 of the electric heat wire 14 is projectingly provided on outer circumference surface of roughly center part of the rib 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric heating type fusion splicing joint for connecting thermoplastic resin pipes.

[0002]

2. Description of the Related Art Conventionally, as an electric heating type fusion splicing joint for connecting thermoplastic resin pipes of polyethylene or the like, an electric heating wire is provided in the vicinity of the inner peripheral surface of a pipe receiving port of a socket-like joint having pipe receiving ports on both sides. There is known a so-called fusion splicing in which is embedded.

[0003]

However, in the fusion-bonded joint, if the polyethylene surface of the fusion-spliced portion has oxidation or dirt, sufficient joint strength cannot be exhibited, and therefore, the surface of the end portion of the polyethylene pipe. There is a problem in that it is difficult to grasp at a glance whether or not the pipe end portion is inserted into the joint receiving portion by the necessary fusion length, without the need for scraping.

The present invention solves the above problems of the conventional fusion splicing joint, does not require cutting of the fusion splicing surface of the connecting portion of the thermoplastic resin pipe or the thermoplastic resin pipe joint, and is capable of receiving the joint. The purpose of the present invention is to provide a fusion splicing joint in which it can be easily confirmed whether or not a necessary fusion splicing length has been inserted into the mouth.

[0005]

According to a first aspect of the present invention (the first aspect of the present invention), a disk-shaped rib is provided on the outside of a substantially central portion of a short tubular thermoplastic resin body, and both sides of the rib are protruded. The main body of is a spout, and heating wires that generate heat by energization are buried near the outer peripheral surface of any of the spouts, and the lead terminals of the heating wires are protruded on the outer peripheral surface of the central portion of the rib. It is a joint.

The invention according to claim 2 of the present application (invention 2)
Has a curved tubular thermoplastic resin body on both sides as outlets, and has a side surface outside the base end portion of the outlet of the body, with which the end face of the tube into which the outlet is inserted can abut. A rib is projected, and a heating wire that generates heat by energization is embedded near the outer peripheral surface of any of the outlets, and a lead terminal of the heating wire is projected on the outer peripheral surface of the rib or the outer peripheral surface of substantially the central portion of the main body. It is a fusion splicer.

The invention according to claim 3 of the present application (invention 3)
The present invention 1 is such that any of the side surfaces of the rib is a flat surface with which the entire circumference of the end surface of the tube into which the spigot is inserted can come into contact, and at least one groove is provided in the radial direction.
Alternatively, it is the fusion splicer of the second invention.

The invention according to claim 4 of the present application (invention 4)
Is the fusion splicing according to any one of the first through third aspects of the present invention, wherein the heating wire embedded in the outlet is provided near the open ends on both sides of the main body and in the main body portion excluding the ribs.

The invention according to claim 5 of the present application (present invention 5)
Is the fusion splicing according to any one of the first through fourth aspects of the invention, wherein the outer diameter of each of the outlets is substantially the same over the entire length of the outlet.

The invention according to claim 6 of the present application (invention 6)
Is the fusion spliced joint according to any one of the first to fifth aspects of the present invention, wherein the thermoplastic resin is polyethylene.

The invention according to claim 7 of the present application (invention 7)
Is a fusion spliced joint according to any one of the first to sixth aspects of the present invention, in which the outer diameters of the outlets at both ends of the body are different from each other.

[0012]

In the fusion-bonding joint of the present invention 1, disk-shaped ribs are projected on the outside of the substantially central portion of the thermoplastic resin main body having a short tubular shape, and the main bodies on both sides of the rib serve as outlets. A heating wire that generates heat by energization is also embedded in the vicinity of the outer peripheral surface of the, and since the lead terminal of the heating wire is projected on the outer peripheral surface of the substantially central portion of the rib, by heating the electric heating wire by energizing,
The inner peripheral surface of the pipe at the pipe end and the outer peripheral surface of the outlet are fusion-bonded.
The inner peripheral surface of the pipe end portion is not soiled or oxidized because the protective cover put on immediately after the production is left attached until just before the fusion splicing work. Therefore, when fusion-splicing using the fusion joint of the present invention, cutting of the pipe surface is not necessary.

In the fusion splicer of the second aspect of the present invention, a curved tubular main body made of thermoplastic resin is used as an opening on both sides, and the insertion opening is inserted outside the base end of the insertion opening of the main body. A rib having a side surface with which the end face of can abut can be projected, and a heating wire that generates heat by energization is buried near the outer peripheral surface of any of the outlets.
Since the lead terminal of the heating wire is projected on the outer peripheral surface of the rib or the outer peripheral surface of the central portion of the main body, by heating the electric heating wire by energization, the inner peripheral surface of the pipe end and the outer periphery of the outlet The faces are fusion spliced. The inner peripheral surface of the pipe end portion is not soiled or oxidized because the protective cover put on immediately after the production is left attached until just before the fusion splicing work. Therefore, when fusion-splicing using the fusion joint of the present invention, cutting of the pipe surface is not necessary.

Furthermore, a lead terminal for the heating wire is provided on the outer peripheral surface of the rib or the outer peripheral surface of the central portion of the main body. Since they are in contact with each other, it is possible to visually confirm whether or not the pipe end is firmly in contact with the rib side face when the fusion spout opening is inserted into the pipe, and the insertion into the pipe is not complete. It is easy and certain to check whether there is any.

Each of the disk-shaped ribs or the side surface of each of the ribs is a flat surface with which the entire circumference of the end surface of the pipe into which the spigot is inserted can come into contact, and at least one or more grooves are axially formed on the surface. When it is provided, the molten resin flows out through the groove to the outside, so that it is easy to see that the air at the molten portion escapes and the fusion is completely performed.

Furthermore, the heating wire buried in the outlet is
When it is provided at both ends of the fusion-bonded joint and the outlet other than the rib, the portion without the heating wire does not melt and functions as a so-called cold zone, and the molten resin is blocked in the zone and melted at the melting point. The pressure is high and the fusion is complete.

Further, when the outer diameters of the outlets at both ends of the main body are different from each other, the pipes having different diameters can be fusion-bonded to each other.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a fusion splicer of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of an example of the fusion splicer of the present invention, and FIG. 2 is a partial sectional side view thereof.

A pipe P1 in which the fusion-bonded joint 1 of the present invention is used,
P2 is a thermoplastic synthetic resin pipe such as a polyethylene pipe, a polypropylene pipe, or a polyvinyl chloride pipe, and is preferably applied to a polyethylene pipe. The body of the fusion splicer 1 may be appropriately selected and determined depending on the pipe type to be connected. That is, when the pipes P1 and P2 are made of polyethylene, the body of the fusion splicing joint 1 of the present invention may be made of polyethylene.

The fusion-bonding joint 1 has a short tubular main body 12 and a disk-shaped rib 13 projecting from the outside of the substantially central portion of the main body 12, and the main body portions on both sides of the rib 13 serve as outlets 121 and 122. The heating wire 14 that generates heat when energized is embedded in the vicinity of the outer surface of each of the outlets 121 and 122, and the lead terminal 15 of the heating wire 14 is projectingly provided on the outer peripheral surface 131 of the rib 13.

Both side surfaces 132 and 133 of the rib 13 are planes perpendicular to the tube axis of the main body 12, and the outer peripheral surfaces of the outlets 121 and 122 can be fitted with tubes to be fused.
The outer diameters are substantially the same in the length direction. Further, at least one groove 134 is radially provided on each of the both side surfaces 132 and 133 in the radial direction on each surface.

The depth, width and number of the grooves 134 are not particularly limited, and when the inner diameters of the pipes P1 and P2 are large, the amount of resin that melts at the connection portion increases, so that the grooves 134 are correspondingly formed. The depth, width, and number of lines should be increased.

The heating wire 14 is not particularly limited as long as it is a heating wire that generates heat when energized. Further, the heating wire 14 is embedded in the vicinity of the outer peripheral surfaces of the outlets 121 and 122, and in the vicinity of the ends of the outlets 121 and 122 and the rib 13 portion.

Therefore, the heat-generating portion is only the buried portion of the heating wire 14, and the ends of the outlets 121 and 122 and the rib 13 are formed.
The area of does not generate heat and acts as a cold zone. It is melted by the heating wire 14 that has been energized and generated heat, and the outlet 12
The molten resin such as polyethylene that has flowed in the direction of the ends of Nos. 1 and 122 is cooled in the cold zone and does not flow out from the molten portion. That is, the molten resin does not flow out into the connected pipes P1 and P2.

Similarly, since the portion of the rib 13 is also a cold zone, the resin melted in the vicinity thereof flows into the grooves 134 provided on the side surfaces 132 and 133 of the rib 13 and flows out from there. Therefore, by confirming the resin flowing out from the groove 134, it is possible to easily confirm whether or not the fusion is surely performed.

The spouts 121, 12 of the fusion splicer 1 of the present invention.
2 The outer surface must be made of the same material as the thermoplastic synthetic resin pipes P1 and P2 connected by the main joint 1, but it does not necessarily mean that the entire joint 1 must be made of the same material. That is, the inlets 121 and 122 that are fusion-spliced with the pipes P1 and P2 must be made of the same material as the pipe, but the rib 13 is particularly preferable as long as it has excellent electric insulation, heat resistance, and compression resistance. Not limited. For example, the outlet 21,
When 22 is polyethylene, the rib 13 may be made of polyethylene, other thermoplastic resin, fiber reinforced resin, pottery, or the like.

The lead terminal 15 is an outer peripheral surface 131 of the rib 13.
It is provided so as to project. Therefore, the mounting portion of the lead terminal 15 of the rib 13 must be made larger than the outer diameter of the lead terminal 15, but the pipes P1 and P2 to be fused are formed.
The thickness of the side surface of the rib 13 that abuts the tube end may be smaller than this (see FIG. 3).

Since the lead terminal 15 is provided on the outer peripheral surface 131 of the rib, the power line is connected by using a power source similar to a power source by a normal electric fusion joint, and the outlets 121 and 122 are connected.
Even when they generate heat and are fusion-bonded, they do not interfere with fusion-bonding.

A method of fusion-bonding pipe ends to each other using the fusion-bonding joint 1 is as follows. That is, the fusion splicer 1 of the present invention is individually packaged in a bag and supplied in a sealed state. Therefore, the outer surface of the fusion splicer 1 is in a state free from contamination and oxidation until it is taken out from the bag. Also, the pipe P1,
The pipe ends of P2 are individually supplied in a state of being sealed by a pipe end protection cover, etc. When connecting pipes, cut the pipe end faces as necessary and cut them into a predetermined length. To be
Therefore, at the time of connection, the inner peripheral surfaces of the ends of the pipes P1 and P2 are not contaminated and are not oxidized. Of course, if contamination or oxidation is a concern, it goes without saying that a new pipe end face may be exposed by cutting the pipe end face.

The spouts 121, 1 of the fusion joint 1 in this state
22 is inserted into the pipe ends of the pipes P1 and P2, and it is confirmed whether all the pipe ends are in uniform contact with the spouts 121 and 122 of the fusion splicing joint 1. Then, the pipes P1 and P2 are connected to each other. Grip and fix with a normal fusion splice clamp (not shown). When clamped by a clamp or the like, the fusion splicer 1 and the pipe P
It can be easily visually determined whether or not P1 and P2 have been correctly arranged.

When the fusion splicing joint 1 and the pipes P1 and P2 are correctly arranged, a power source is connected to the lead terminal 15 to energize according to a conventional method, and it is confirmed that the molten resin flows out from the groove 134. The fusion splicing is completed.

Next, still another example of the fusion splicing joint of the present invention will be described with reference to FIGS. In this fusion splicer 2, the outer diameters of the outlets 221 and 222 at both ends of the main body 22 are different from each other, and the inner surface of the central portion of the main body 22 has a smaller outer diameter than the inner surface of the large outlet 221. It is the same as the fusion splicing described with reference to FIGS. 1 to 3, except that it is a tapered surface that gradually decreases in diameter toward the inner surface of 222. Corresponding drawing numbers are given in the drawings, and detailed description thereof is omitted.

The method of fusion-splicing the pipe ends using the fusion-bonding joint 2 is as follows. The spout 221 having a large outer diameter of the fusion splicer 2 is provided with a pipe P3 having a large diameter.
And the insertion port 222 having a small pipe diameter is inserted into the pipe end of the pipe P4 having a small pipe diameter. After confirming whether all the pipe ends are in uniform contact with the spouts 221 and 222 of the fusion splicing joint 1, the pipes P3 and P4 are connected to each other with an ordinary fusion splicing clamp (not shown) or the like. Hold and fix. When clamped by a clamp or the like, the fusion-bonded joint 2 and the pipe P
It is possible to easily visually judge whether or not 3 and P4 are properly arranged.

When the fusion splicing joint 2 and the pipes P3 and P4 are correctly arranged, a power source is connected to the lead terminal 25 to energize according to a conventional method, and it is confirmed that the molten resin flows out from the groove 234. The fusion splicing is completed.

Next, still another example of the fusion splicer of the present invention will be described with reference to FIGS. 6 and 7. The fusion splicing joint 3 has a curved tubular main body 32 made of a thermoplastic resin, and both sides of the spout 321,
It is set to 322. Outlet 321, 322 of the main body 32
The pipes P5 and P6 with the spigot inserted outside between the base ends of the
A rib 33 having a side surface capable of contacting the entire circumference of the end face of is protruded. A heating wire 34, which generates heat when energized, is embedded in the vicinity of the outer peripheral surface of each of the outlets 321, 322, and a lead terminal 35 of the heating wire 34 is projectingly provided on the outer peripheral surface of the rib 33.

Both side surfaces 332 and 333 of the rib 33 are planes perpendicular to the tube axis of the main body 32, and the outer peripheral surfaces of the outlets 321 and 322 can be fitted with tubes to be fused.
The outer diameters are substantially the same in the length direction. Further, at least one groove 334 is radially provided on each of the both side surfaces 332, 333 in the radial direction.

The location where the heating wire 34 is buried is the outlet 321,
Near the outer peripheral surface of 322, and the outlets 321 and 322
Is a portion excluding the vicinity of the end and the rib 33. Therefore, the heat generating portion is only the buried portion of the heating wire 34, and the end portions of the outlets 321, 322 and the rib 33 portion do not generate heat and act as a cold zone. The molten resin such as polyethylene that has been melted by the heating wire 34 that has been energized and generated heat and has flowed toward the end portions of the spouts 321 and 322 is cooled in the cold zone and does not flow out from the melting point to the outside. That is, the molten resin does not flow out into the connected pipes P5 and P6.

Similarly, since the ribs 33 are also cold zones, the resin melted in the vicinity thereof flows into the grooves 334 provided on the side surfaces 332 and 333 of the ribs 33 and flows out from there. Therefore, by confirming the resin flowing out from the groove 334, it can be easily confirmed whether or not the fusion is surely performed.

The spouts 321 and 3 of the fusion splicer 3 in this state
22 is inserted into the pipe ends of the pipes P5 and P6, and it is confirmed whether all the pipe ends are in uniform contact with the outlets 321 and 322 of the fusion splicing joint 3, and then the pipes P5 and P6 are connected to each other. Grip and fix with a normal fusion splice clamp (not shown). When clamped by a clamp or the like, the fusion-bonded joint 3 and the pipe P
5. Whether or not P6 and P6 are correctly arranged can be easily visually determined.

After the fusion splicing joint 3 and the pipes P5 and P6 are correctly arranged, a power source is connected to the lead terminal 35 to energize in accordance with a conventional method, and it is confirmed that the molten resin flows out from the groove 334. The fusion splicing is completed.

In this example, the rib 33 is provided on the outer side between the base end portions of the outlets 321 and 322 of the main body 32, but the rib is the outlet 32 of the main body 32.
The lead terminals of the heating wire may be provided only on the base end portions of the first and the second heaters 322, and may protrude from the outer peripheral surface of the main body 32 at the substantially central portion. In this case, it goes without saying that the heating wire is not embedded in the main body portion between the ribs. Also, the outer diameters of the outlets 321 and 322 at both ends of the main body 32 may be different from each other so that pipes having different diameters can be fusion-bonded to each other.

[0042]

As described above, the fusion splicing joint of the present invention does not require cutting of the fusion splicing surface of the thermoplastic resin pipe, and it is easy to determine whether or not the fusion splicing length has been inserted. It is a fusion splicer that can be confirmed.

[Brief description of drawings]

FIG. 1 is an external perspective view of an example of a fusion joint of the present invention.

FIG. 2 is a partial cross-sectional view of FIG.

FIG. 3 is a partial cross-sectional view of another example of the fusion splicing joint of the present invention.

FIG. 4 is an external perspective view of yet another example of the fusion splicing joint of the present invention.

FIG. 5 is a cross-sectional view of a main part of still another example of the fusion splicer of the present invention.

FIG. 6 is an external perspective view of yet another example of the fusion splicing joint of the present invention.

FIG. 7 is a cross-sectional view of yet another example of the fusion splicing joint of the present invention.

[Explanation of symbols]

1, 2 and 3 fusion splicing joints 12, 22, 32 main body 121, 122, 221, 222, 321, 322 spout 13, 23, 33 rib 131, 231, 331 outer peripheral surface 132, 133, 232, 233 of rib, 332, 333 rib side surfaces 134, 234, 334 groove 14, 24, 34 heating wire 15, 25, 35 lead terminals P1, P2, P3, P4, P5, P6 tube

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3H019 GA03                 4F211 AA04 AD12 AG08 AG28 AH11                       TA01 TC11 TD07 TN08 TN31

Claims (7)

[Claims] 1. A disk-shaped rib is provided on the outside of a substantially central portion of a short tubular thermoplastic resin main body, and the main bodies on both sides of the rib are used as outlets. A heating wire that generates heat is embedded in the fusion joint, and a lead terminal of the heating wire is provided so as to project from an outer peripheral surface of a substantially central portion of the rib. 2. A curved tubular thermoplastic resin main body is provided with an opening on both sides, and an end surface of a pipe into which the insertion opening is inserted can abut on an outer side of a base end portion of the insertion opening of the main body. A rib having a side surface is projected, and a heating wire that generates heat by energization is buried near the outer peripheral surface of any of the outlets, and a lead terminal of the heating wire is provided on the outer peripheral surface of the rib or the outer peripheral surface of substantially the center of the main body. A fusion-bonded joint characterized by being projected. 3. Each of the side surfaces of the rib is a flat surface with which the entire circumference of the end surface of the pipe into which the spigot is inserted can abut, and at least one groove is provided in the radial direction. The fusion splicing joint according to claim 1 or 2, characterized in that. 4. The heating wire embedded in the outlet is provided near the open ends on both sides of the main body and in the main body portion excluding the ribs. The fusion splicing according to item. 5. The fusion splicer according to claim 1, wherein the outer diameters of the respective outlets are substantially the same over the entire length of the outlets. 6. The thermoplastic resin according to claim 1, wherein the thermoplastic resin is polyethylene.
The fusion splicing according to item. 7. The fusion splicer according to claim 1, wherein the outer diameters of the outlets at both ends of the main body are different from each other.