JPH0214713Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a conductive pipe joint with a detachment prevention function.

Prior Art In conduits through which electrical wires such as telephone lines are inserted, conductive pipes such as cast iron pipes are used to prevent harmful induced currents from being generated in the internal electrical wires. It is also necessary that one pipe and the other pipe in the pipe joint are electrically connected to each other. For this reason, in the conventional technique shown in Utility Application No. 59-97835, as shown in FIGS. It has been proposed that a conductive chip 35 covering the outer surface of the heel portion 34 of the sealing material 33 is integrally formed. This conductive chip 35 is brought into pressure contact with the inner surface of the socket 31 and the outer surface of the socket 32 as the sealing material 33 is compressed, thereby establishing electrical continuity between the socket and the socket. A conductive pipe joint similar to this is published in Utility Model Publication No. 49-86429.
It is also disclosed in the publication.

Problems to be Solved by the Invention However, with the conventional configuration shown in FIG. However, there is a problem that the conductive chip 35 may be corroded by this water intrusion. In addition, when conduits are buried in areas prone to ground subsidence or under roads with heavy road loads,
There is also a problem in that a large ejection force acts between 1 and the insertion port 32, which may cause them to separate from each other.

Therefore, the present invention aims to prevent the corrosion of the conductive chip due to water intrusion, and also to prevent separation between the socket and the socket.

Means for Solving the Problems The present invention forms a socket at one end of a conductive pipe, and a socket inserted into the socket at the other end of another conductive pipe. forming an annular sealing material pressure contact surface on the inner surface of the socket;
An inner tapered surface whose diameter gradually increases toward the back of the socket, and a back end surface following the inner tapered surface are formed in order from the opening end, and between the inner tapered surface and the outer surface of the socket. , providing a detachment prevention ring having an outer circumferential tapered surface that abuts the inner circumferential tapered surface, an inner circumferential latching blade that abuts the outer surface of the insertion port, and an elastic tongue piece that abuts the inner circumferential end surface; An annular first sealing material is press-fitted between the pressure contacting surface and the outer surface of the socket, and the outer surface of the heel portion of the first sealing material is covered to form a space between the sealing material pressure contacting surface and the outer surface of the socket. A plurality of circumferential conductive chips to be electrically connected are formed integrally with the first sealing material, and an annular chip is formed between the sealing material pressure contact surface and the outer surface of the socket on the side closer to the receptacle opening end than the first sealing material. 2
The sealing material is press-fitted.

Effect: According to the above configuration, the second sealing material prevents water from entering the first sealing material from outside the tube, and thus prevents this water from coming into contact with the conductive chip, which leads to corrosion of the conductive chip. Prevention is planned. When the joint portion is joined, the detachment prevention ring is held at a predetermined position within the socket by the action of the elastic tongue. When an ejection force is applied between the socket and socket, the detachment prevention ring, which was pressed against the inner peripheral tapered surface of the socket by the elastic tongue with a moderate force,
This extraction force strongly presses against the inner tapered surface, and the wedge action of this inner tapered surface causes the latch blade to bite into the outer surface of the socket, providing a reliable separation prevention function. .

Embodiment Hereinafter, an embodiment of the present invention will be described based on the drawings. In Fig. 1, 1 is a socket formed at one end of a conductive tube, and 2 is a socket formed at the other end of another conductive tube connected to said tube. These pipes are manufactured by centrifugal casting using ductile cast iron, and the socket 1 and the socket 2 are formed as as-cast. On the inner surface of the socket 1, in order from the opening end toward the back side, there is an inner flange 3, an annular sealing material pressure contact surface 5 in the tube axis direction having an annular projection 4, and a diameter gradually increasing toward the back side of the socket. An inner circumferential tapered surface 6, an inner end surface 7 in the pipe radial direction continuous with the inner circumferential tapered surface 6, and an inner tapered surface 8 whose diameter gradually decreases toward the back of the socket are formed. On the other hand, the insertion port 2 is formed with a tip tapered surface 9 that comes into contact with the inner tapered surface 8 .

Between the seal material pressure contact surface 5 and the socket outer surface 10,
An annular first sealing material 11 that engages with the annular projection 4
and an annular second sealing material 12 located closer to the socket opening end than the first sealing material 11 are press-fitted. As shown in FIGS. 2a and 2b, the first sealing material 11 is engaged with the annular protrusion 4 and the sealing material 1
1, and a valve part 14 made of soft rubber to perform a sealing function when compressed and deformed.
The structure is such that the two are integrally formed. At a plurality of positions in the circumferential direction of the heel portion 13, the heel portion 13
The sealing material pressure contact surface 5 and the outer surface of the socket 10
A conductive chip 15 made of copper that comes into contact with is integrally formed.

The second sealing material 12 is arranged between the first sealing material 11 and the inner flange 3. This second
The sealing material 12 is molded from rubber having the same hardness as the valve part 14 of the first sealing material 11, and
As shown in the figure, it has a heel portion 16 sandwiched between the inner flange 3 and the first sealing material 11, and a fin portion 17 in the radial direction of the tube. The fin portion 17 is formed thin, so that it is deformed in the direction of the tube axis when the socket 2 is inserted into the socket 1, and is brought into close contact with the outer surface 10 of the socket due to the elastic force based on this deformation. It is configured to perform the intended sealing function.
Moreover, since it is thin, the resistance during insertion of the socket 2 can be reduced, and dimensional tolerances of the socket 2 can be easily accommodated.

In addition, although the first sealing material 11 and the second sealing material 12 are shown as separate bodies in the above, a structure in which both the sealing materials 11 and 12 are bonded together with an adhesive or the like and integrated is also possible. Good too.

Between the inner circumferential tapered surface 6 and the outer surface 10 of the insertion port, there is provided a detachment prevention ring 18 that is divided in the circumferential direction and has a diameter reducing force. This detachment prevention ring 18 is made of hardened stainless steel, and as shown in FIGS. 4a and 4b, the inner peripheral tapered surface 6
a first outer circumferential tapered surface 19 that comes into contact with the first outer peripheral tapered surface 19;
It has a second outer circumferential tapered surface 20 formed at a steeper angle with respect to the tube axis than the first outer circumferential tapered surface 19 on the socket opening end side than the outer circumferential tapered surface 19 . Also, inside the detachment prevention ring 18, there are first and second holes that contact the outer surface 10 of the socket.
Inner peripheral retaining blades 21 and 22 are formed.

A plurality of elastic tongues 24 in the circumferential direction are attached to the end surface 23 of the detachment prevention ring 18 on the back side of the socket, which contact the back end surface 7 of the socket 1 . This elastic tongue piece 24 has a metal plate body 25 having a bent structure as shown in FIG. 5 welded to the end face 23, and the elastic force of this bent part directs the ring 18 toward the opening end of the socket. It is energized by As another elastic tongue piece 24, as shown in FIG. 6, a rubber piece 26 that can come into contact with the rear end face 7 may be fixed to the end face 23 with an adhesive 27.

In such a configuration, when joining the joint portion, both sealing materials 11 and 12 and the detachment prevention ring 18 are first placed in the socket 1. Then, the detachment prevention ring 18 is pressed against the inner circumferential tapered surface 6 by the action of the elastic tongue piece 24, and is held centered with respect to the socket 1, thereby making it possible to easily insert the socket 2. becomes. That is, the elastic tongue piece 24
If the ring 18 does not have this, the ring 18 will be displaced in the direction of the larger diameter of the inner tapered surface 6, that is, toward the back of the socket, and fall to the lower end of the inner tapered surface 6, causing misalignment with respect to the socket 1. Although it is difficult to insert the socket 2, the action of the elastic tongue piece 24 makes it possible to insert the socket 2 without such a problem.

By inserting the insertion port 2, the first sealant 11 is compressed between the sealing material pressure contact surface 5 and the outer surface 10 of the insertion port, and the joint portion is sealed. At the same time, the conductive chip 15 is connected to the sealing material pressure contact surface 5 and the outer surface 1 of the insertion port.
0, thereby establishing electrical continuity between the socket and the socket. Note that the portion that the chip 15 comes into contact with must be left unpainted or coated with conductive paint to ensure continuity.

When the socket 2 is inserted, the second sealing material 12 is also compressed, and the space between the sockets on the socket opening end side relative to the first sealing material 11 is sealed. This prevents water from entering the inside of the socket 1 from outside the pipe.
Corrosion of the conductive chip 15 can be prevented.

When an extraction force is applied to the insertion port 2, the detachment prevention ring 18 is pressed against the inner tapered surface 6 due to friction between the outer surface 10 of the insertion port and the inner peripheral latching blades 21, 22. Then, due to the wedge action of the inner circumferential tapered surface 6, the detachment prevention ring 18 is strongly tightened to the outer surface 10 of the socket. At the same time, the ring 1 is moved in a direction in which the second outer circumferential tapered surface 20 approaches the inner circumferential tapered surface 6.
8 falls down, and the first inner circumferential retaining blade 21 touches the outer surface 10 of the socket.
It will eat into. These make it possible to obtain a reliable detachment prevention function.

Effects of the Device As described above, according to the present invention, the action of the second sealing material can prevent water from entering the first sealing material from outside the pipe, thereby preventing this water from coming into contact with the conductive chip. This not only prevents corrosion of the conductive chip, but also prevents corrosion in areas prone to ground subsidence and road surface loads due to the action of the detachment prevention ring, which is held in place within the socket by an elastic tongue. Even if the pipe is buried under a large road, a reliable separation prevention function can be obtained.

[Brief explanation of the drawing]

Figure 1 is a sectional view of one embodiment of the present invention, Figures 2a and b are detailed views of the first sealing material, and Figure 3 is the second sealing material.
4a and 4b are detailed views of the detachment prevention ring, FIG. 5 is a view showing an example of the elastic tongue piece, and FIG. 6 is a view showing another example of the elastic tongue piece. FIGS. 7a and 7b are cross-sectional views of a conventional example. 1... Socket, 2... Socket, 4... Annular projection, 5
... Sealing material pressure contact surface, 6 ... Inner peripheral tapered surface, 7 ...
... Back end surface, 10 ... Outer surface of the socket, 11 ... First sealing material, 12 ... Second sealing material, 13 ... Heel part, 15 ... Conductive chip, 18 ... Separation prevention ring, 19...first outer peripheral tapered surface, 20...
...Second outer circumferential tapered surface, 21...First inner circumferential latching blade, 22...Second inner circumferential latching blade, 24...Elastic tongue piece.

Claims (1)

[Claims for Utility Model Registration] A socket is formed at one end of a conductive pipe, and an insertion port inserted into the socket is formed at the other end of another conductive pipe. , an annular sealing material pressure contact surface on the inner surface of the socket;
An inner tapered surface whose diameter gradually increases toward the back of the socket, and a back end surface following the inner tapered surface are formed in order from the opening end, and between the inner tapered surface and the outer surface of the socket. , providing a detachment prevention ring having an outer circumferential tapered surface that abuts the inner circumferential tapered surface, an inner circumferential latching blade that abuts the outer surface of the insertion port, and an elastic tongue piece that abuts the inner circumferential end surface; An annular first sealing material is press-fitted between the pressure contacting surface and the outer surface of the socket, and the outer surface of the heel portion of the first sealing material is covered to form a space between the sealing material pressure contacting surface and the outer surface of the socket. A plurality of circumferential conductive chips to be electrically connected are formed integrally with the first sealing material, and an annular chip is formed between the sealing material pressure contact surface and the outer surface of the socket on the side closer to the receptacle opening end than the first sealing material. 2
A conductive pipe joint with a separation prevention function, which is characterized by a pressure-fitted sealing material.