JPH0438153Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a pipe joint that enables electrical connection, and particularly to a pipe joint that has improved conductivity and can be used repeatedly.

[Conventional technology and its issues]

It has long been known that large currents are passed through coiled tubes for industrial use, but when a large current is passed through a coiled tube, the tube generates heat, so cooling The temperature rise in the pipes is suppressed by flowing water.

By the way, since the length of the above-mentioned pipes is limited, multiple pipes are connected using pipe joints to obtain the required length. Conventionally, the pipe joints used in this field are:
As shown in FIGS. 3 to 5, it is called a bite joint and includes a main body 12, a sleeve 13, and a cap nut 14.
A thread 14' is cut on the outer periphery of the main body 12, and a conical sealing surface A is formed on the outside of the through hole. A cylindrical straight surface B is formed in connection with the small diameter end side of the sealing surface A.
The straight surface B serves as a guide when the tube P is inserted.

Further, an angled surface C opposite to the sealing surface A is provided at the bottom of the straight surface B on the tube P insertion side. If the pipe P to which it is applied is thin-walled, the cap nut 14
This is to prevent the pipe P from being crushed inward by the tightening force.

The inner conical portion D of the cap nut 14 is a portion that comes into contact with the sleeve 13 when it is tightened, and has two functions: transmitting the tightening force of the sleeve 13 and firmly holding the pipe P through the sleeve 13. ing. In addition, in order to make the head side of the sleeve 13 (the right side in the figure) adhere tightly to the pipe P, an angle difference (the former is slightly gentler than the latter) is made with respect to the conical part D of the cap nut 14. A conical part E is provided,
It is made to come in contact with the pipe P at a position close to it.

On the other hand, vibrations to the joint are received by the conical portion D of the cap nut 13 rather than by the cutting edge F of the sleeve 13, thereby preventing concentration of stress on the biting portion. In addition, sleeve 13
When tightened, the cutting edge F at the tip bites into the pipe P, as shown in Figure 5, and the central part is bent and compressed, and its strong spring action prevents the cap nut from vibrating. Designed to prevent loosening.

However, as described above, in the conventional pipe joint, the sleeve 13 needs to be curved, so it needs to be thin. Furthermore, since the cutting edge F is a biting connection, the current capacity is small, and if a large current is applied, there is a risk of heat generation and melting. Furthermore, since the sleeve 13 bites into the pipe P and is connected at the connection part, there is a problem that if a failure occurs in the pipe joint, both the pipe P and the pipe joint cannot be reused.

In view of the above points, this invention eliminates the risk of heat generation or melting when a large current is passed through the pipe, and when a failure occurs in the pipe fitting, all that is needed is to replace the failed part, and the rest can be reused. The purpose of this invention is to provide a pipe joint that has a connection function.

[Means to solve the problem]

In order to achieve the above object, the present invention has a spanner fitting part in the center part, a cap nut is screwed to the outer periphery of both ends, and a through hole for receiving the pipe is bored in the center part. An O-ring made of rubber or plastic, and a holding ring and a conductive ring made of conductive material are sequentially inserted into the main body, which has a step formed by making the inner diameter of both ends of the hole larger than that of the center, toward the inside and outside of the step. The inner hole of the retaining ring is tapered to become gradually larger toward the inside of the body, and the rear inner hole of the cap nut is tapered to become smaller toward the outside of the body. be.

[Function] In the pipe fitting of the present invention constructed as described above, the watertightness of the pipe fitting is guaranteed by pressing the O-ring against the insertion part of the pipe with the tapered part of the inner hole of the holding ring, and the holding ring and the conductive ring A sufficient contact area between the pipe connected by the pipe and the pipe joint body is ensured.
Therefore, there is no digging or deformation of the metal material in the pipe joint, so if a failure occurs in the pipe joint, just replace that part and everything else can be reused. Furthermore, there is no risk of heat generation or melting at the joint.

〔Example〕

Next, the embodiments of the present invention are shown in the attached drawings, FIGS. 1 and 2.
This will be explained with figures.

The main body 2 of the pipe joint 1 has a hexagonal outer periphery in the center for fitting a spanner into it, and male threads 4 are cut at both ends for screwing together cap nuts 3 and 3', and connections can be made from both ends. Holes 5 and 5' for receiving the pipes P and P' pass through the holes 5 and 5', and steps 6 and 6' with larger inner diameters are formed at both ends of the holes 5 and 5'. The tapered portions of the O-ring 7 and the presser rings 8, 8' are arranged to fit within the space.

Therefore, when inserting the pipes P, P' which are connected to each other into the holes 5, 5' of the main body 2, the O-rings 7, Holding rings 8, 8' and a conductive ring 9 are interposed. That is, the O-ring 7 and the retaining rings 8, 8' fitted on the outside of the pipes P, P' are housed inside the steps 6, 6' at both ends of the main body 2, and the conductive ring 9 is inserted into the cap nuts 3, 3'. Rear tapered surface 1
The cap nuts 3, 3' are screwed onto the male screw 4 of the main body 2 so that they fit inside the 0. At this time, main body 2
Insert a wrench into the central hexagonal part to prevent the main body 2 from rotating together.

In this embodiment, the diameters of the holes 5 and 5' in the main body 2 are different on the left and right sides, but it goes without saying that they may be the same diameter.

As mentioned above, the cap nut 3 is attached to the male screw 4 of the main body 2.
3' are screwed together, the holding rings 8, 8' and O-ring 7 are pushed through the conductive ring 9, and the conductive ring 9 comes into close contact with the steps 6, 6' between the pipes P, P' and the main body 2, and The watertightness of the joint 1 is guaranteed. At this time, the tapered portion 11 of the inner hole of the retainer rings 8, 8'
As a result, the O-ring 7 is pressed against the boundary between the pipes P and P' inserted into the holes 5 and 5' and the main body 2, thereby further improving watertightness.

Further, by screwing the cap nuts 3, 3' together as described above, the pipes P, P' and the main body 2 are connected to the conductive ring 9, the holding rings 8, 8', and the cap nuts 3, 3'.
3'.

The tapered surface 10 provided at the rear of the hole of the cap nuts 3, 3' is for making the pipes P, P' and the cap nuts 3, 3' come into stronger contact via the conductive ring 9. Note that if the conductive ring 9 has a trapezoidal cross-sectional shape along the tapered surface 10, an even stronger contact force can be obtained.

The retaining rings 8, 8' have a larger outer diameter on the side of the cap nuts 3, 3';
This is to improve the fit in 3'.

In this embodiment, the main bodies 2 of the presser rings 8, 8'
The angle of the side tapered portion 11 was set to 60°, but it is 45° to 70°.
The effect can be obtained within the range of. Outside this range, either the adhesion of the O-ring 7 to the pipes P, P' or the adhesion to the main body 2 deteriorates.

〔effect〕

The pipe joint according to the present invention can be used repeatedly because there is no permanent deformation or biting in the connection part. Furthermore, since the electrical contact surface can be made larger, the current capacity is increased, and there is no risk of burning or melting due to heat generated at the connection portion due to energization.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view of an embodiment of the pipe joint according to the present invention, Fig. 2 is an enlarged sectional view of a retaining ring used in the pipe joint according to the present invention, and Figs. 3 to 5 are conventional It is an explanatory diagram of an example. 1... Pipe joint, 2... Main body, 3, 3'... Cap nut, 4... Male thread, 5, 5'... Hole, 6, 6'...
...Step, 7... O-ring, 8, 8'... Holding ring, 9... Conductive ring, 10... Tapered surface of cap nut, 11... Tapered portion of holding ring, P,
P′...tube.

Claims (1)

[Scope of utility model registration request] It has a spanner fitting part in the center, a cap nut is screwed on the outer periphery of both ends, and a through hole for receiving the pipe is bored in the center, and the inner diameter of both ends of the through hole is larger than the center part. An O-ring made of rubber or plastic is attached to the main body with a step formed thereon.
Holding rings and conductive rings made of conductive materials,
While sequentially inserting the step toward the inside and outside,
The inner hole of the retaining ring is tapered to become larger toward the inside of the main body, and the inner hole at the rear of the cap nut is tapered to become smaller toward the outside of the main body. Fittings.