JPH09273677A - Coming-out preventing pipe coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably connect a coming-out preventing pipe coupling even if the angle between a socket and a spigot is a little large. SOLUTION: A spigot 4 formed on the end of one pipe 3 is inserted into a socket 2 formed on the end of the other pipe 1, and an annular seal material 5 is compressed between the inner peripheral surface of the socket 2 and the outer peripheral surface of the spigot 4. An annular lock ring housing groove 18 is formed on the inner periphery of the socket 2, and an outer peripheral groove 19 is formed on the outer periphery of the spigot 4. A first lock ring 20 normally fastening is fitted to the lock ring housing groove 18 and the outer peripheral groove 19. A second lock ring 21 normally expanding and capable of being engaged with the first lock ring 20 and whose width dimension in the pipe axial direction is changed along the circumferential direction is housed in the part in which the first lock ring 20 is not housed along the width direction of the lock ring housing groove 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint for preventing separation.

[0002]

2. Description of the Related Art One type of conventional separation prevention pipe joint is shown in FIG. Here, a receiving port 2 is formed at an end of one ductile cast iron pipe 1 to be joined to each other, and an inserting end inserted into the receiving port 2 is provided at an end of the other ductile cast iron pipe 3. A mouth 4 is formed. An annular sealing material accommodation groove 5 is formed on the inner periphery of the receiving port 2, and an annular sealing material 6 made of rubber is accommodated in the accommodation groove 5.
Then, the seal material 6 is compressed between the inner peripheral surface of the seal material accommodation groove 5 and the outer peripheral surface of the insertion slot 4, thereby achieving a required sealing function.

An annular lock ring receiving groove 8 having a rectangular cross section is formed on the inner periphery of the receiving port 2 on the opening side of the sealing material receiving groove 5.
Are formed. Also, on the outer periphery of the insertion port 4,
An outer peripheral groove 9 having a rectangular cross section is formed so as to face the lock ring receiving groove 8 when it is inserted to a predetermined position inside the receiving port 2. Then, these lock ring receiving grooves 8
A lock ring 10 having a rectangular cross-section and divided in the circumferential direction is housed across the outer peripheral groove 9. A tapered surface 11 is formed on the outer periphery of the tip of the insertion slot 4.

When joining the pipe joint having such a structure, the insertion port 4 is inserted into the receiving port 2 in which the seal material 6 and the lock ring 10 are housed in advance. Then, the lock ring 10 and the sealing material 6 are expanded in diameter by being guided by the tapered surface 11 of the insertion opening 4, so that the insertion opening 4 enters the inner circumference of the lock ring 10 and the sealing material 6. And
When the outer peripheral groove 9 faces the lock ring accommodating groove 8, the tight lock ring 10 fits into the outer peripheral groove 9 so that the state shown in FIG.

In this way, the lock ring 10 engages with both the lock ring receiving groove 5 of the receiving opening 2 and the outer peripheral groove 9 of the insertion opening 4, thereby exerting a required detachment preventing function. .

[0006]

However, with such a structure, the lock ring 10 has the receiving groove 8 and the outer peripheral groove 9.
On the other hand, since it is necessary to fit the pipe in the state where there is no substantial gap in the pipe axis direction over the entire circumference, when the socket 2 and the socket 4 are joined, the axial centers of the socket 2 and the socket 4 are made to interfere with each other. If the angle between them is large, the accommodation groove 8 and the outer peripheral groove 9 along the tube axis direction
The positions of and are displaced from each other, and the lock ring 10 cannot properly enter the outer peripheral groove 9 of the insertion slot 4, so that the required separation preventing function cannot be exerted. For this reason, in this type of conventional separation prevention pipe joint, the angle range in which the receiving port 2 and the insertion port 4 can be joined, that is, the joinable angle range is very small.
There is a problem that it is usually about 1 ° or less.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to reliably join the separation preventing pipe joint even if the angle between the receiving and inserting openings is slightly large.

[0008]

In order to achieve this object, the present invention inserts an insertion opening formed at the end of the other tube into a receiving opening formed at the end of one tube. In a pipe joint in which an annular seal material is compressed between the inner peripheral surface of the receiving opening and the outer peripheral surface of the insertion opening, an annular lock ring accommodating groove is formed on the inner periphery of the receiving opening and An outer peripheral groove is formed on the outer periphery, and a first lock ring that fits tightly is fitted into the lock ring accommodating groove and the outer peripheral groove, and the first lock ring is accommodated along the width direction of the lock ring accommodating groove. A second lock ring, which can be engaged with the first lock ring and which can be engaged with the first lock ring and whose width dimension in the pipe axis direction changes along the circumferential direction, is accommodated in a portion which is not formed.

With such a structure, the width dimension of the second lock ring is smaller than that of the other portions in a part of the second lock ring in the circumferential direction. Then, in this part, the first
The total width dimension of the lock ring and the second lock ring is smaller than the width dimension of the housing groove. Therefore, in this portion, the first lock ring can be fitted into both the accommodation groove and the outer peripheral groove in a state where the accommodation groove and the outer peripheral groove are displaced from each other in the axial direction in a certain range.
That is, it is possible to join the receiving opening and the insertion opening to each other so as to exert a required detachment preventing function in a state where the axes of the receiving opening and the insertion opening have a certain angle with each other.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described.
Based on FIGS. 1 to 4, the same members as those shown in FIG. 5 are designated by the same reference numerals and will be described in detail. That is, as shown in FIG. 1, the lock ring receiving groove 18 of the receiving port 2 having a rectangular cross section has a groove width dimension along the pipe axis direction.
It is formed larger than the conventional one shown in FIG.
The outer peripheral groove 19 of the insertion opening 4 having a rectangular cross section is formed with a groove width dimension equivalent to that of the conventional one shown in FIG. That is,
Compared to the outer peripheral groove 19 of the insertion port 4, the lock ring accommodation groove of the receiving port 2
18 is formed so that the dimension of the groove width along the pipe axis direction becomes larger.

Into the outer peripheral groove 19 of the insertion slot 4, the inner peripheral side portion of the first lock ring 20, which is formed in a rectangular shape in transverse cross section, is fitted into the outer peripheral groove 19 in the circumferential direction. The width dimension of the first lock ring 20 in the tube axis direction is formed to be substantially the same as the width dimension of the outer peripheral groove 19. Also the first
The outer peripheral portion of the lock ring 20 has a width dimension smaller than that of the accommodation groove 18 of the receiving port 2, but is fitted in the accommodation groove 18.

In the accommodation groove 18 of the receiving port 2, this accommodation groove 18
A second lock ring 21 having a rectangular cross section is inserted into the portion along the width direction in which the first lock ring 20 is not housed so as to open in the circumferential direction. The second lock ring 21 is formed so that its inner diameter is larger than the outer diameter of the insertion opening, so that it does not engage with the insertion opening 4, and, on the other hand, the first lock ring 21. It is configured to engage with the outer peripheral side portion of 20. Then, the second lock ring 21 is formed so that the width dimension in the pipe axis direction changes along the circumferential direction.

That is, for example, in the pipe top portion in FIG. 1, the widthwise dimension of the second lock ring 21 is made approximately equal to the widthwise dimension of the first lock ring 20, and
The maximum width dimension portion 22 of the lock ring 21 is formed.
The widthwise dimension of the housing groove 18 is the first at the top of the pipe.
And the width of the second lock rings 20 and 21 is substantially equal to the total width of the lock rings 20 and 21. Further, in the pipe bottom portion in FIG. 1, that is, in the portion at a distance of 180 ° from the maximum width dimension portion 22 in the circumferential direction, the width dimension is the minimum,
23 are formed. The width dimension between the maximum width dimension portion 22 and the minimum width dimension portion 23 is configured to gradually change. In other words, the second lock ring 21 is inclined from both sides in the width direction at an angle θ from the maximum width dimension portion 22 to the minimum width dimension portion 23 when viewed from the side as shown in FIG. Is configured. Alternatively, as shown in FIG. 4, only one side in the width direction may be inclined at an angle θ.

In such a structure, the receiving port 2 and the insertion port 4
When they are joined to each other, the insertion port 4 is inserted into the inside of the receiving port 2 with the first and second lock rings 20 and 21 and the sealing material 6 accommodated in the inner periphery of the receiving port 2 in advance. . Then, since the second lock ring 21 is open-ended, the insertion slot 4 passes through the inside of the second lock ring 21 as it is. On the other hand, since the first lock ring 20 is self-locking, the insertion port 4 expands the diameter of the first lock ring 20 when passing.

The first lock ring 20 can be fitted into the outer peripheral groove 19 of the insertion slot 4 only when facing the outer peripheral groove 19 of the insertion slot 4. That is, at the pipe top, the width dimension of the portion of the receiving groove 18 of the receiving port 2 excluding the maximum width dimension portion 22 of the second lock ring 21, that is, the portion 24 of the first locking ring 20 is the outer circumference of the insertion port 4. Since the width dimension of the groove 19 is almost the same, only when the position of this portion 24 and the outer peripheral groove 19 are aligned, the first lock ring 20 is provided on both of this portion 24 of the accommodating portion 18 and the outer peripheral groove 19. Can fit.

On the other hand, at the bottom of the pipe, the receiving groove 18 of the receiving port 2 is formed.
Minimum width dimension 23 of the second lock ring 21 fitted in
And the total width dimension of the first lock ring 20 fitted in the outer peripheral groove 19 of the insertion slot 4 is smaller than the width dimension of the accommodation groove 18. Therefore, for example, considering the case where the second lock ring 21 is in contact with the side wall of the accommodation groove 18 as shown in the figure, the portion of the accommodation groove 18 excluding the minimum width dimension portion 23 of the second lock ring 21. That is, the first lock ring 20
The width dimension of the portion 24 accommodating is larger than the width dimension of the outer peripheral groove 19 of the insertion slot 4. Therefore, this minimum width dimension part
At the bottom of the pipe where 23 exists, not only when the outer peripheral groove 19 of the insertion port 4 exists at the same position as at the top of the pipe,
As far as 19 faces the part 24 containing the first locking ring 20, this first locking ring 20
It is possible to fit in both this portion 24 of the receiving groove 18 and the outer peripheral groove 19.

In other words, even when the axes of the receiving port 2 and the insertion port 4 have an angle equal to the inclination angle θ of the second lock ring 21, the first lock ring 20 retains these receiving grooves.
It is possible to fit into both 18 and the outer peripheral groove 19. Therefore, even if there is an angle θ between the receiving opening 2 and the insertion opening 4 as described above, the receiving opening 2 and the insertion opening 4 can be joined to each other so as to exert a required separation preventing function. it can.

Specifically, with such a structure, the angle θ formed by the axes of the receiving port 2 and the insertion port 4 is 2 to 3
Even when the angle is set to about 0 °, the receiving opening 2 and the insertion opening 4 can be joined to each other while maintaining the separation preventing function.

The width dimension of the minimum width dimension portion 23 of the second lock ring 21 can be determined by the required size of the joinable angle θ. Further, in the minimum width dimension portion 23, the width of the first lock ring 20 is smaller than the width of the portion 24 of the housing groove 18, so that the angle θ is formed between the receiving opening 2 and the insertion opening 4 as described above. In addition to being able to join the both at a certain time, it is possible to allow the bending between the receiving opening 2 and the insertion opening 4 after the joining is completed, and to give flexibility to the pipe joint.

[0020]

As described above, according to the present invention, an annular lock ring accommodating groove is formed on the inner periphery of the receiving opening and an outer peripheral groove is formed on the outer periphery of the insertion opening. It is possible to engage the first lock ring with the first lock ring, and engage with the first lock ring at a portion along the width direction of the lock ring housing groove where the first lock ring is not housed. In addition, since the second lock ring having the opening property in which the width dimension in the pipe axis direction changes along the circumferential direction is accommodated, the width dimension of the second lock ring is changed in a part of the second lock ring in the circumferential direction. It can be made smaller than the width dimension of the other portion, and therefore, in this portion, the total width dimension of the first lock ring and the second lock ring fitted in the outer peripheral groove of the insertion opening is accommodated. Depending on the width of the groove Also, the first lock ring can be fitted into both the outer peripheral groove and the receiving groove even when the outer peripheral groove of the insertion slot is displaced in the axial direction within a certain range. The receiving opening and the insertion opening can be joined to each other so that the required detachment preventing function is exhibited in a state where the axes of the opening and the insertion opening have a certain angle with each other.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a separation prevention pipe joint according to the present invention.

FIG. 2 is a side view of the lock ring in FIG.

FIG. 3 is a sectional view of the lock ring of FIG. 2;

FIG. 4 is a cross-sectional view of another example of the lock ring.

FIG. 5 is a cross-sectional view of a conventional separation prevention pipe joint.

[Explanation of symbols]

 2 Receiving port 4 Inserting port 6 Sealing material 18 Lock ring accommodating groove 19 Outer peripheral groove 20 First lock ring 21 Second lock ring

Claims (1)

[Claims] 1. An inner peripheral surface of the receiving opening and an outer peripheral surface of the receiving opening by inserting the insertion opening formed at the end portion of the other pipe into the receiving opening formed at the end portion of one of the pipes. A pipe joint adapted to compress an annular sealing material between the two, wherein an annular lock ring accommodating groove is formed on the inner periphery of the receiving port and an outer peripheral groove is formed on the outer periphery of the insertion port. The first lock ring is fitted in the groove and the outer peripheral groove, and the first lock ring is fitted in the widthwise direction of the lock ring housing groove where the first lock ring is not housed. A separation preventing pipe joint, which accommodates a second lock ring which is openable and whose width dimension in the pipe axial direction changes along the circumferential direction.