JPS606713Y2 - Metal pipe fitting device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a coupling device for rotatably joining a relatively small diameter metal pipe to a component such as a socket while maintaining airtightness.

Conventionally, this type of coupling device has a metal pipe 1, as shown in FIG.
The joint body 12 inserted into the socket 2 is screwed and fixed to the socket 2, and two annular rings 113 and 14 are attached to the outer periphery of the joint body 12.
The O-ring 3 is fitted into one annular groove 13 in close contact with the inner surface of the socket, while the other annular groove 14 is engaged with the tip of a set screw 10 screwed into the socket 2 in the radial direction. The pipe 1 is rotatably joined to the socket 2, but it requires a lot of work to process the joint body and fit it to the metal pipe, resulting in a significant increase in cost. Cutting the material weakens its strength, so it could not be applied to thin-walled metal pipes.

In addition, in the device disclosed in Japanese Unexamined Utility Model Publication No. 52-6sici, when a force is applied to the metal tube 1'' in the direction of pulling it out of the socket 2', the adhesion of the O-ring 3' to the inner surface of the socket 2' becomes weak. As a result, the sealing performance of the O-ring 3' deteriorates.

Therefore, the present inventor first developed a metal tube 1 as shown in Fig. 2.
The two annular bulging layers 16 and 17 are integrally molded, leaving a guide part 17 of an appropriate length at the tip of the socket 2', and an O-ring 3' that closely contacts the inner surface of the socket 2' is fitted into the guide part 17. On the other hand, a set screw 10' screwed into the socket 2' in the radial direction
A joint device was proposed in Japanese Utility Model Publication No. 52-681, in which an O-ring is inserted into and engaged between both annular bulging lumps 16 and 15; During the connection work, the O-ring easily comes off from the guide part, and not only is the O-ring often lost, but also the inner surface of the large diameter hole that the O-ring 3' contacts in the socket 2', the inner surface of the large diameter hole, and the guide part 17. The inner surface of the small-diameter hole into which the socket fits must be smoothed, which increases the cost.Moreover, since the guide part at the tip of this socket is fitted into the hole of the socket, it is not as large as the socket shown in Fig. 1 above. This method cannot be applied to joining a metal tube to a socket having an inner diameter.

The present invention improves the above-mentioned drawbacks by eliminating the guide part at the tip of the metal tube in the latter joint device and fitting the O-ring and socket-side screw between both annular bulges. It is.

To explain the drawings of the embodiment below, the tip of the metal tube 1 having an outer diameter d is connected to the inner diameter D1 of the O-ring 3 that is in close contact with the inner surface 2'' of the socket 2, and the stepped enlarged tube 4 has an outer diameter d1. The enlarged tube 4 is formed with an external cut at its tip.

forms a first annular bulging lump 5 having a slightly smaller diameter than the outer diameter D2 of the O-ring 3, and a second annular bulging lump of the same shape is formed at a position separated by an appropriate distance 1 from the first annular bulging lump 5. Model 6,
As shown in FIG. 3, a ring body 7 is slidably fitted between the two annular bulges 5 and 6, and the O-ring is inserted between the first annular bulge 5 and the ring body 7. An annular groove 9 into which the socket 3 is fitted is formed, and an annular groove 11 into which the tip of a set screw 10 screwed into the socket 2 in the radial direction is formed between the second annular bulging lump 6 and the ring body 7. It is formed by forming.

With this configuration, the O-ring 3 is connected to the first annular bulging lump 5.
Since the O-ring 3 is fitted into the annular groove 9 formed between the O-ring 3 and the ring body 7, once the O-ring 3 is fitted, it will not come off and the O-ring 3 will not come off.
While the ring can be inserted into or removed from the socket without losing it, the socket 2 only needs to have a smooth finish on the inner surface 3 that the O-ring 3 is in close contact with.
Since there is no need to finish smooth the inner surface of the small diameter hole at the back, the number of steps required for the processing can be reduced.

Then, when the metal tube 1 is inserted into the socket 2,
While the outer peripheries of the first and second annular bulging lumps 5, 6 are in contact with the inner surface 2'' of the socket 2, the interval 1 between both the annular bulging lumps 5, 6 is such that there is an annular groove 9 for an O-ring, a ring Since the width is increased by providing the body 7 and the annular groove 11 for the set screw, the inclination of the axis of the metal tube 1 with respect to the socket 2 is adjusted to the above-mentioned interval 1.
The wide first and second annular bulges 5 and 6 securely hold the bulge and prevent rattling. Moreover, the tip of the set screw 10 screwed into the socket 2 can be fixed to the second annular bulge. Since the set screw 10 is inserted into the annular groove 11 formed between the ring body 6 and the ring body 7, the set screw 10 does not come into contact with the O-ring, so the O-ring is not damaged by the set screw.

Further, when a force is applied to the metal tube 1 in the direction of pulling it out from the socket 2 due to the ring body 7 being slidably fitted, the force in the pulling direction is transmitted from the set screw 10 to the ring body 7. acts to tighten the O-ring 3 in the axial direction through the Since they are pressed more closely together, the sealing performance of the O-ring 3 does not deteriorate.

As described above, in the present invention, the insertion portion of the metal tube into the socket is formed into an enlarged tube, and the enlarged tube has a first annular bulging lump formed at its tip, and the first annular bulging lump. A second annular bulging lump of the same shape is formed at a position separated by an appropriate distance from the annular bulging lump, and a ring body is slidably fitted into the enlarged tube between the two annular bulging lumps, and the ring body and the second annular bulging lump are slidably fitted. An O-ring that is in close contact with the inner surface of the socket is fitted into the annular groove between the first annular bulging lump, while an O-ring that fits into the annular groove between the ring body and the second annular bulging lump is fitted into the outer surface of the socket. This is made by fitting the tip of a set screw that is screwed together so that it protrudes from the inner surface of the O-ring, allowing it to be connected to and disassembled from the socket without losing the O-ring, reducing manufacturing costs, and ensuring a strong connection. Moreover, since the part of the metal tube that is inserted into the socket is formed into an enlarged tube, even if the socket has a considerably larger diameter than the metal tube, the metal tube can be joined to it. This is possible.

Moreover, even if a force is applied to the metal tube connected to the socket to pull it out of the socket, the sealing performance provided by the O-ring will not deteriorate.

[Brief explanation of drawings]

1 and 2 are sectional views showing the conventional example, FIG. 3 is an exploded view of the device according to the present invention, and FIG. 4 is an assembled view of the device according to the present invention. 1...Metal tube, 2...Socket, 4.
...Enlarged canal part, 5...First annular bulging lump,
6...Second annular bulge, 7...Ring body, 8...Third annular bulge, 3...O
Ring, 9... annular groove, 10... set screw.

Claims (1)

[Scope of utility model registration request] The insertion portion of the metal tube into the socket is shaped into an enlarged tube, and the enlarged tube has a first annular bulge formed at its tip and is spaced an appropriate distance from the first annular bulge. forming a second annular bulging lump having the same shape at the same position, and slidably fitting a ring body into the enlarged tube at a portion between both the annular bulging lumps;
An O-ring that closely contacts the inner surface of the socket is fitted into the annular groove between the ring body and the first annular bulge, while an O-ring is fitted into the annular groove between the ring body and the second annular bulge. , a metal pipe coupling device in which the tip of a set screw screwed into the socket so as to protrude from the outer surface to the inner surface of the socket is fitted.