JP2997671B1 - Joint - Google Patents

Abstract

An object of the present invention is to provide a joint capable of preventing leakage of a transport fluid when an external force acts in a drawing direction of a resin pipe in a high temperature state. A joint body (12) has a cylindrical shape, and has a contact surface (16), an inclined surface (17) and a receiving surface (18) formed therein. A second inner peripheral groove 28 is provided on the inner peripheral surface of the joint body 12 between the contact surface 16 and the inclined surface 17, and a third seal ring 29 is fitted therein. A pair of lock rings 3
4a and 34b are formed in an annular shape and have a plurality of restriction pieces 36. The pressing body 19 has a cylindrical shape, and a second seal ring 27 is provided on an inner peripheral surface thereof. And joint 3
7, the third seal ring 29 is connected to the pipe 11
Are located more inward than the pair of lock rings 34a, 34b engaged with the lock ring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint for resin pipes used for water pipes, hot water pipes, floor heating, road heating, and the like.

[0002]

2. Description of the Related Art As a conventional pipe joint of this type, for example, one disclosed in Japanese Patent No. 2686105 is known. This pipe joint is formed into a cylindrical socket that allows insertion of a pipe, a lock ring, a backup ring, and a seal ring that are disposed in an inner diameter enlarged portion provided therein, and is screwed to the outer periphery of the socket. , And a cap for preventing each ring from coming out of the pipe joint.

When connecting a pipe to a pipe joint, first, a lock ring,
Store in the order of backup ring and seal ring.
Next, a cap is screwed onto the outer periphery of the socket, and the lock ring, the backup ring, and the seal ring are positioned and fixed in the socket. Finally, a pipe is inserted into the socket through an opening formed in the center of the socket. As a result, the gap between the pipe and the socket is sealed by the seal ring, preventing the transport fluid from leaking out of the pipe joint, and preventing the pipe from coming out of the pipe joint by the engagement of the lock ring with the pipe. .

[0004]

However, when a strong external force acts on the resin pipe in the pulling direction at a high temperature, the outer side of the portion of the pipe where the lock ring is engaged is directed in the pulling direction. As the pipe extends, the thickness of the pipe in the extended portion decreases, and the outer diameter of the pipe decreases. For this reason, a gap is formed between the inner peripheral surface of the seal ring and the outer peripheral surface of the pipe located in the direction in which the pipe is pulled out of the lock ring, and the transport fluid flowing through the pipe leaks out of the pipe joint from the gap. There was a problem.

The present invention has been made by focusing on the problems existing in such prior art. An object of the present invention is to provide a joint that can prevent leakage of a transport fluid when an external force acts in a drawing direction of a resin pipe in a high temperature state.

[0006]

In order to achieve the above object, the joint according to the first aspect is provided with an annular receiving surface in a cylindrical joint main body, and has an annular shape and protrudes inward. At least one lock ring having a plurality of regulating pieces is engaged with the receiving surface, and a slit is formed between the regulating pieces.
In both cases, an arc-shaped hole is formed at the base end of the slit,
With screwed into a female screw portion formed in the joint body external threads of the cylindrical pressing body for positioning and fixing the locking ring abutment surface provided on the joint body the resin pipe through a pressing body The lock ring is engaged with the outer peripheral surface of the pipe by being inserted until it comes into contact with the lock ring so as to prevent the pipe from coming off. A seal ring for preventing leakage from the end to the outside is fitted into a groove provided at least on the inner peripheral surface of the joint body between the contact surface and the lock ring.

According to a second aspect of the present invention, in the first aspect of the invention, the pipe has a temperature of 85 ° C. and a pressure of 1.0 kgf.
/ Mm ² when applied with a tensile load of 20% or more.

[0008] joint according to claim 3 is the invention according to claim 1 or claim 2, wherein the pipe is Ru der those formed by polyolefins.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail . As shown in FIGS. 1 and 2, the pipe 11 is formed in a cylindrical shape from a polyolefin, for example, cross-linked polyethylene or polybutene, and is used for water supply piping and the like. When a tensile load of 1.0 kgf / mm ² is applied to the pipe 11 at 85 ° C., the pipe 11 has a property of extending 20% or more from the original length of the pipe 11.

The joint body 12 is formed in a tubular shape from brass or bronze, and has a first male screw portion 13 formed on one end of the outer periphery thereof so that it can be screwed into a pipe 10 such as a water supply pipe.
The nut part 14 is formed on the outer periphery of the other end of the joint body 12. Then, when the joint body 12 and the pipe 10 such as a water supply pipe are screwed and unfastened, a wrench or the like is engaged with the nut portion 14 so that the joint body 12 can be easily rotated. Has become.

The first female screw portion 15 is formed on the inner circumference at the other end of the joint body 12. The contact surface 16 is provided on the joint body 12.
An annular portion is provided in the inner back portion so as to be orthogonal to the axis of the joint body 12. The inclined surface 17 is formed in a ring shape in the joint body 12 so that the inner diameter increases from the outer edge of the inner peripheral surface connected to the contact surface 16 toward the first female screw portion 15. The receiving surface 18 is provided on the outer peripheral edge of the inclined surface 17 so as to be orthogonal to the axis of the joint body 12.
2 is formed in an annular shape.

The pressing body 19 includes a cylindrical portion 20 made of brass or bronze, and a grip portion 21 formed smaller than the outer shape of the nut portion 14 of the joint body 12. The second male screw part 22 is formed on the outer peripheral surface of the cylindrical part 20 and is screwed to the first female screw part 15 of the joint body 12. The pair of locking portions 23 are cut out at opposing positions on the outer periphery of the end of the grip portion 21. When screwing the pressing body 19 to the joint body 12 and releasing the same, by engaging a wrench or the like with the locking portion 23,
The pressing body 19 can be easily rotated.

The outer peripheral groove 24 is formed at the center of the outer peripheral surface of the pressing body 19, and a first seal ring 25 formed in a ring shape by rubber is fitted as a seal member therein. Then, when the pressing body 19 is screwed into the joint body 12, the first seal ring 25 is connected to the pressing body 19 and the joint body 1.
2 is sealed. The first inner circumferential groove 26 is formed slightly closer to the grip 21 than the inner circumferential center of the pressing body 19, and a second seal ring 27 having a circular cross section as a seal member is fitted therein.

The second inner peripheral groove 28 is formed on the inner periphery of the joint body 12 between the inclined surface 17 and the contact surface 16. A third seal ring 29 as a seal member having a circular cross section is fitted therein.

As a result, when the pipe 11 is inserted into the joint body 12 through the pressing body 19, the gap between the pipe 11 and the pressing body 19 is sealed by the second seal ring 27, and the third seal ring 29 Thereby, the gap between the pipe 11 and the joint body 12 is sealed.

As shown in FIG. 3, the core ring 30 includes a cylindrical portion 31 made of brass or bronze, and a flange portion 32 formed at one end thereof. The annular portion 42 is formed in an annular shape from the inner end surface 32a of the flange portion 32 to the outer end surface 32b. The inclined surface 43 is formed such that the diameter decreases from the outer edge of the annular portion 42 toward the inside.

The tubular portion 31 is fitted into the pipe 11 to prevent the pipe 11 from being deformed inward due to thermal expansion or the like. The inclined portion 33 is formed so as to have a slightly reduced diameter from the base end side of the cylindrical portion 31 toward the distal end.

Then, as shown in FIG. 5, the tubular portion 31 is fitted inside the pipe 11. At this time, the inclined portion 33 can cope with a variation in the inner diameter of the pipe 11 and facilitates insertion of the tubular portion 31 into the pipe 11. The inner end surface 32 a of the flange 32 engages with the end surface 11 a of the pipe 11.

Further, as shown in FIG. 6, when the pipe 11 is inserted into the joint body 12 in this state, the inclined surface 43
Thereby, the flange portion 32 can be smoothly inserted without being caught by the second seal ring 27 and the third seal ring 29. In addition, since the outer end surface 32b is formed in a flat shape, the outer end surface 32b comes into close contact with the contact surface 16 and can exhibit a sealing function.

As shown in FIG. 1, the end of the pipe 11 in which the core ring 30 is fitted is inserted into the joint body 12 via the pressing body 19, and the outer end surface 32 b of the flange 32 is inserted into the joint body 12. The end surface of the pressing body 19 and the end surface of the cylindrical portion 31 of the core ring 30 are located at the same position when they are brought into contact with the contact surface 16. Therefore, by observing the positional relationship between the end face of the coring 30 and the end face of the pressing body 19 from the outside of the translucent pipe 11, the outer end face 32b
Is in contact with the contact surface 16 in the joint body 12.

The introduction passage 45 is formed from one end in the joint body 12 to the contact surface 16. When the joint body 12 is screwed into the pipe 10 such as a water supply pipe, a liquid as a transport fluid passes through the introduction passage 45. And circulates into the pipe 11. The inclined wall 46 is formed such that the inner diameter of the inner peripheral surface of the introduction path 45 on the nut part 14 side decreases toward the first female screw part 15 side. The inner diameter of the reduced diameter portion 47 is smaller than the inner diameter of the introduction passage 45 from the inner peripheral edge of the inclined wall 46 on the first female screw portion 15 side.

Then, the end of the pipe 11 into which the core ring 30 is fitted is inserted into the joint body 12 through the press body 19, and the outer end surface 32 b of the flange 32 is brought into contact with the contact surface 16 in the joint body 12. , The inner diameter of the core ring 30 and the inner diameter of the reduced diameter portion 47 formed in the introduction path 45 are the same. Therefore, for example, when the flow rate of the liquid in the tubular body 10 is suddenly changed due to rapid opening / closing of a valve, mixing of gas, or the like, and a water hammer phenomenon in which an abnormal pressure occurs in the tubular body 10 occurs, the inclined wall 46 causes An abnormal pressure can be prevented from being applied to the outer end surface 32b of the flange portion 32 of the coring 30. Further, the reduced diameter portion 47 allows the abnormal pressure to be released from the inner peripheral surface of the coring 30 toward the pipe 11.

The pair of lock rings 34a and 34b are obtained by polishing the surface of a molded product obtained by molding stainless steel into a predetermined shape by a press molding method by any one of a barrel processing method, a shot peening method and a sand blast method. Of these, a wet high-speed rotary barrel processing method capable of reliably chamfering is preferable. As a result, the entire surfaces and edges of the lock rings 34a and 34b can be chamfered, and burrs generated during press molding can be removed.

Then, the obtained pair of lock rings 34
In order to maintain a predetermined strength, the thicknesses a and 34b are preferably formed in a range of 0.2 to 0.6 mm, and are formed in a range of 0.3 to 0.5 mm. Is more preferred. Also, as shown in FIGS. 4A and 4B,
Each of the lock rings 34a and 34b includes an annular base ring 35 and a plurality of restricting pieces 36 projecting inward from the base ring 35 by the same length.

The tip of each regulating piece 36 is formed in an arc shape,
A biting portion 36a that cuts into the pipe 11 is formed, and a corner portion 36b that restricts the restricting piece 36 from biting into the pipe 11 more than a required amount is formed at the base end. The restriction piece 36 is bent and formed to extend at 45 degrees from the inner peripheral edge of the base ring 35 with respect to the base ring 35. Further, the pipe 11 can be easily inserted from the base end side to the distal end side of the restricting piece 36, and the inserted pipe 11 is prevented from coming off.

The notch 39 is formed in all the adjacent regulating pieces 36.
An arc-shaped notch is formed in the center between the restricting pieces 36 and the base ring 35 so as to correspond to the depth at which the restricting pieces 36 bite into the pipe 11. Notch 39
Is set such that the pipe 11 can be prevented from coming off when the portion from the tip of the regulating piece 36 to the bottom of the cutout portion 39 bites into the pipe 11.

The V-shaped slit 40 has a predetermined depth from the center of the bottom of the notch 39 to the base ring 35, that is, allows the deformation of the restricting piece 36 when the pipe 11 is inserted into the lock rings 34a and 34b. It is formed only to the required depth. Form between the restriction pieces 36 of the lock ring 34
From the base end of the formed V-shaped slit 40,
, That is, the base ends of both side edges of the regulating piece 36
A circular hole 49 is punched from the hole to the base ring 35
It is formed. For this reason, for example,
Stress caused by abnormal pressure, etc.
End portions of both side edges of the regulating piece 36 engaged with the pipe 11
To avoid stress concentration on
I have. Then, stress is collected at the base end portions of both side edges of the regulating piece 36.
The diameter of the hole 49 is 1.0-2.
Preferably, it is set to 0 mm. In this embodiment
It is set to 1.2 mm. In addition, the holes as described above
Since the diameter of 49 is set, the base end of the regulating piece 36
Is provided with the required rigidity, and two points shown in FIG.
As shown by the dashed line, the restriction piece 36 is easy to spread outward.
ing.

As shown in FIGS. 4 (b) and 4 (c) , the biting portion 36 of each of the restriction pieces 36 of the lock rings 34a and 34b.
The edges of a and the corner 36b are chamfered in an arc shape having a radius of 0.02 to 0.2 mm by barrel processing.

When inserting the pipe 11 into the joint 37, first, the pipe 11 is passed through the second seal ring 27 and the pair of lock rings 34a and 34b. Further, the pipe 11 is passed through the third seal ring 29.
At this time, the biting portion 36a of the restricting piece 36 of the pair of lock rings 34a, 34b is formed in an arc shape, and the edges are chamfered. Therefore, pipe 11
It is possible to prevent the outer surface from being damaged. Now, the pipe is attached to the lock ring 34 of the joint 37.
When inserting 11, two points shown in FIG.
As shown by the dashed line, the restriction piece 36 is easy to spread outward.
ing. Therefore, the restriction piece 36 added to the pipe 11
Load is reduced, and pipe 11 can be easily attached to lock ring 34
Can be inserted. In addition, the lock ring 34
When the pipe 11 is inserted, the outer surface of the pipe 11
While maintaining the engagement force with the lock ring 34.
Can be prevented. In addition, fittings
For example, when using 37, water hammer phenomenon
Occurs, the pipe 11 connected in the joint 37
On the other hand, abnormal pressure is applied in the exit direction. Same as that
Sometimes, a lock ring engaged with the outer surface of the pipe 11
Base portions of both side edges of the restriction piece 36 of the
Stress concentrates at the intersection of
Acts to cause cracks. At this time, the circular shape
The stress is evenly distributed by the holes 49 of both sides of the regulating piece 36.
Concentration of stress on the base end of the edge can be avoided.
As a result, according to the joint 37, the restriction piece 3
6 to prevent cracks from forming at the base end of both side edges.
The life of the ring 34 is extended and the pie
Can be prevented from lowering the engagement force with the
You. Therefore, the pipe 11 is prevented from coming out of the joint 37.
Can be stopped.

As shown in FIG. 2, the spacer 48 is interposed between the pair of lock rings 34a and 34b. The spacer 48 is preferably formed of stainless steel, brass or resin, and particularly preferably formed of stainless steel or brass, in order to improve the strength such as impact resistance. The spacer 48 has a thickness of 0.1 mm.
The width of the ring portion 48a corresponds to the width of the base ring 35 of the pair of lock rings 34a and 34b.

In the pair of lock rings 34a and 34b, one lock ring 34a is
5 is engaged on the receiving surface 18 of the joint body 12,
6 is located so as to have a gap between the inclined surface 17. The spacer 48 is engaged on the receiving surface 18 via the base ring 35 of one of the lock rings 34a. And, the other lock ring 34b has its base ring 3
5 is engaged on the receiving surface 18 via the base ring 35 and the spacer 48 of one lock ring 34a.

Therefore, the pair of lock rings 34a, 3a
4b can be prevented from moving in the axial direction and the circumferential direction. When the ends of the pipe 11 are inserted into the pair of lock rings 34a and 34b, the restriction pieces 36 located in two stages each slightly spread outward, and the tip ends are engaged with the outer periphery of the pipe 11 in two stages. Are combined. As a result, the pipe 11 is prevented from falling off by the joint body 12.

The joint body 12, the pair of lock rings 34a and 34b, the spacer 48, and the core ring 3
A joint 37 is constituted by the pressing body 19 and the pressing member 19. Next, the operation of the joint 37 as described above will be described.

First, the first male screw portion 13 of the joint body 12 is screwed into the pipe 10 such as a water supply pipe, and the nut portion 14 is screwed by a spanner or the like, and the joint body 12 is fastened and fixed to the pipe 10. Next, one lock ring 34 a is fitted into the joint body 12, the base ring 35 is engaged with the receiving surface 18 in the joint body 12, and
Is made to have a gap between itself and the inclined surface 17.

Subsequently, the spacer 48 is engaged with the receiving surface 18 via the base ring 35 of one of the lock rings 34a. Then, the base ring 35 of the other lock ring 34b is replaced with the base ring 35 and the spacer 48.
On the receiving surface 18 via the lock ring 34b and the restricting piece 36 of the other lock ring 34b and one lock ring 34
There is a gap between the restriction piece 36 and the restriction piece 36a.

Then, the second male screw portion 22 of the pressing body 19
Is screwed into the first female screw portion 15 of the joint body 12, and a wrench or the like is engaged with the engaging portion 23 to push the pressing body 19 to the joint body 12.
To screw. At this time, the lock rings 34a, 34b
Are positioned and fixed immovably in the axial and circumferential directions by the distal end of the cylindrical portion 20 of the pressing body 19 with the spacer 48 interposed therebetween, and the joint body 12 is fixed by the first seal ring 25. The gap between the pressure member and the pressing body 19 is sealed.

Subsequently, as shown in FIG.
0, the cylindrical portion 31 is fitted into the pipe 11 from the inclined portion 33, and the inner end surface 32a of the flange portion 32 is connected to the end surface 11a of the pipe 11.
Push until it engages.

Then, as shown in FIG.
The end of the pipe 11 on the side where 0 is fitted is inserted into the joint body 12 via the pressing body 19. At this time, the positional relationship between the end surface of the cylindrical portion 31 of the core ring 30 and the end surface of the pressing body 19 is visually observed, and the pipe 11 is pushed in until they are at the same position, and the outer end surface 32 b of the flange portion 32 is inserted into the joint body 12. Is brought into contact with the contact surface 16. In addition, a pair of lock rings 3
Since the biting portion 36a of the restriction piece 36 of 4a, 34b is formed in an arc shape, it is possible to prevent the outer surface of the pipe 11 from being damaged.

As a result, as shown in FIG. 1, the gap between the pipe 11 and the joint body 12 is sealed by the third seal ring 29, and the pipe 11 is sealed by the second seal ring 27.
The gap between the pressure member 19 and the pressing member 19 is sealed, and the end of the pipe 11 is airtightly connected to the joint 37.

At this time, when a strong external force acts in the drawing direction of the pipe 11 in a high temperature state, the outside of the pipe 11 extends beyond a portion where the pair of lock rings 34a and 34b are engaged. Further, the thickness of the extended portion of the pipe 11 is reduced, and the outer diameter of the pipe 11 is reduced. At this time, the liquid that has leaked from the end of the pipe 11 on which the core ring 30 has been fitted is sealed by the third seal ring 29.
a, 34b is prevented from leaking from the end of the pressing body 19 through the engaging portion of the regulating piece 36, through the gap between the second seal ring 27 and the pipe 11 having a smaller outer diameter. can do. Further, the leaked liquid is inclined surface 1
7. Furthermore, it is possible to prevent leakage from the gap between the first seal ring 25 and the joint body 12. Therefore, leakage of the liquid from the joint 37 can be prevented.

[0041] As described above, according to the next hand 37, the following effects can be exhibited. According-to the joint hand 37, for example, with the pipe 11 is exposed to a high temperature state above 85 ° C., when an external force in the pull-out direction of the pipe 11 is applied, a pair of lock ring 34a, the pressing member from 34b 19
The side pipe 11 extends in the drawing direction. Therefore, the thickness of the pipe 11 is reduced and its outer diameter is reduced, and a gap is formed between the second seal ring 27 and the pipe 11. However, the gap between the joint body 12 and the pipe 11 is sealed by the third seal ring 29 on the end face 11 a side of the pipe 11 in the joint 37. Therefore, leakage of the liquid from the joint 37 can be prevented.

The pipe 11 to be used in-joint hand 37,
It is made of polyolefin such as cross-linked polyethylene and polybutene, and has a property of elongation of 20% or more when a tensile load of 1.0 kgf / mm ² is applied at 85 ° C. Therefore, when this pipe 11 is used, it is possible to more reliably prevent the liquid from leaking from the joint 37.

According to [0043] - joint hands 37, a pair of lock ring 34a, 34b, together with the tip of the restricting piece 36 is formed in an arc shape, it is chamfered at the edges. Therefore, when the pipe 11 is passed through the third seal ring 29, it is possible to prevent the outer surface of the pipe 11 from being damaged.

[0044]

[0045]

[0046]

[0047]

[0048]

The above embodiment can be embodied by being modified as follows. -Changing both or one of the second seal ring 27 and the third seal ring 29 to a seal ring having a U-shaped cross section. At this time, the opening of the seal ring is
It is located on two sides. In the case of such a configuration,
When the liquid as the transport fluid leaks from the end face of the pipe 11, the liquid is stored in the inside of the seal ring through the opening. As a result, it is possible to prevent the liquid from leaking from the joint 37.

The second seal ring 27 is omitted. In such a configuration, even if the pipe 11 on the pressing body 19 side extends in the pulling-out direction from the pair of lock rings 34 a and 34 b and the thickness of the pipe 11 is reduced, the joint body is formed by the third seal ring 29. The gap between the pipe 12 and the pipe 11 can be sealed to prevent the transport fluid from leaking from the joint 37.

The depth of the second inner peripheral groove 28 is reduced, and the third seal ring 29 is fitted. Alternatively, the diameter of the third seal ring 29 is increased while keeping the depth of the second inner circumferential groove 28 as it is. With this configuration, the third
The pressing force on the pipe 11 by the seal ring 29 is strengthened, and the gap between the joint body 12 and the pipe 11 can be more strongly sealed.

The biting portion 36 a at the tip of the lock ring 34 is formed in a square shape, and the cutout portion 39 is formed until it reaches the base ring 35. Further, the regulating piece 36
Chamfering and deburring the edges of Further, the lock ring 34 is any one of 2 to 5 and is engaged with the receiving surface 18. Alternatively, the number of the lock rings 34 to be engaged on the receiving surface 18 is any one of 3 to 5, and spacers 48 are interposed between the lock rings 34 arbitrarily or alternately.

The number of lock rings 34 used in the above embodiment is one or three to five, and the lock rings 34 are engaged with the receiving surface 18. Alternatively, the number of the lock rings 34 to be engaged on the receiving surface 18 is any one of 3 to 5, and spacers 48 are interposed between the lock rings 34 arbitrarily or alternately. With such a configuration, the amount of the restriction piece 36 of the lock ring 34 engaged with the pipe 11 increases, and the pipe 11 can be more reliably prevented from falling out of the joint 37.

Use the joint 37 in a place where water, salt solution, oil, ethylene glycol, etc., flows as a transport fluid. Even in the case of such a configuration, the function of the joint 37 can be reliably exhibited.

The hole 49 is formed in an arc shape so that no corner such as an ellipse or an ellipse is formed. With this configuration, it is possible to prevent stress from concentrating on the corners and to prevent cracks from occurring at the base end of the regulating piece 36.

[0056] - the slits 40 formed to a position reaching the base ring 35, the holes 49 punched to be a base ring 35 from the proximal end of the slit 40. Even in the case of such a configuration, it is possible to prevent stress from being concentrated on the base end portions on both side edges of the regulating piece 36 and to prevent cracks from being generated from the base end portion of the regulating piece 36 on both side edges of the base ring 35. can do.

Further, the technical idea grasped from the embodiment will be described below. · The seal ring has a circular cross section.
The joint according to any one of the above. With this configuration, the gap between the joint body and the pipe can be reliably sealed.

The joint according to any one of claims 1 to 3, wherein a groove is provided on an inner peripheral surface of the pressing body, and a seal ring is fitted in the groove. In such a configuration, during normal use, the cooperation of the seal ring provided between the contact surface and the lock ring can reliably prevent the transport fluid from leaking from the joint.

[0059] The joint according to any one of claims 1 to 3, wherein at least an inner edge of the regulating piece that bites into the pipe is chamfered. With this configuration, it is possible to prevent the outer surface of the pipe from being damaged when the pipe is passed through the seal ring.

[0060] The joint according to any one of claims 1 to 3, wherein the pipe is made of crosslinked polyethylene or polybutene. With this configuration, the function of the joint can be reliably exhibited.

[0061] - said hole coupling as claimed in claim 1 is circular. With this configuration, it is possible to reliably prevent stress from concentrating on the base end portions on both side edges of the regulating piece, and to prevent cracks there.

[0062] - the base end portion of the regulating piece formed integrally with the base ring, joint according to claim 1 hole is formed over the base ring from the proximal end of the side edges of the regulating piece. With this configuration, stress concentration can be reliably prevented, and cracks can be prevented from occurring from the base end portions on both side edges of the regulating piece to the base ring. Therefore, the life of the lock ring can be prolonged, and the engagement force of the regulating piece with the pipe can be reliably prevented from decreasing.

[0063] - coupling as claimed in claim 1 wherein the diameter of the holes is 1.0 to 2.0 mm. With this configuration,
The restriction piece can be easily spread outward while imparting the required rigidity to the base end of the restriction piece. Therefore, the engaging force of the restricting piece on the outer surface of the pipe can be maintained to prevent the pipe from coming off the lock ring, and the pipe can be easily inserted into the lock ring.

[0064]

The present invention is configured as described above, and has the following effects. According to the joint according to the first aspect of the invention, when an external force acts in a drawing direction of the resin pipe in a high temperature state, leakage of the transport fluid can be prevented. Also, due to stress concentration,
Prevents cracks at the base end of the side edge,
The life of the bearing is extended, and the
It can be prevented from lowering. Therefore, the pipe
It is possible to prevent the joint from falling out. Also,
When inserting the pipe into the lock ring,
Reduces the load on the piece, making the pipe easier to lock ring
Can be inserted.

According to the joint of the second aspect of the invention, the effects of the first aspect of the invention can be reliably exhibited. According to the joint of the invention described in claim 3, according to claim 1
Alternatively, the effects described in claim 2 can be more reliably exerted.

[0066]

[Brief description of the drawings]

FIG. 1 is a half sectional view showing the inside of a joint according to an embodiment.

FIG. 2 is an exploded perspective view showing the joint of the embodiment.

FIG. 3 is a sectional view showing the coring of the embodiment.

4A is a plan view showing a lock ring of the embodiment, FIG. 4B is a cross-sectional view showing the lock ring of the embodiment,
FIG. 4C is a sectional view taken along line 4-4 in FIG.

FIG. 5 is a side view showing a state where a coring is fitted into an end of the pipe.

FIG. 6 is an exploded side view showing a state in which a pipe is inserted into the joint body.

[Explanation of symbols]

11 pipe, 12 joint body, 15 first internal thread,
Reference numeral 16: contact surface, 18: receiving surface, 19: pressing body, 22: second male screw portion, 28: second inner circumferential groove portion, 29: third seal ring, 34: lock ring, 36: regulating piece, 37 ... Joints, 40: slits, 49: holes.

Claims (3)

(57) [Claims] 1. A cyclic receiving surface provided in a joint main body which forms a cylindrical, engages in at least one said receiving surface a locking ring having a plurality of restricting piece projecting inwardly an annular shape, before
A slit is formed between the control pieces and the
An arc-shaped hole is formed at the base end of the socket, and the male thread of the cylindrical pressing body for positioning and fixing the lock ring is screwed into the female thread formed in the joint body, and the resin pipe is connected to the pipe. It is configured to be inserted until it comes into contact with the contact surface provided in the joint main body through the pressing body and to engage with the restriction piece of the lock ring on the outer peripheral surface of the pipe to prevent the pipe from coming off,
When the pipe is extended, a seal ring for preventing a transport fluid flowing in the pipe from leaking out of the contact surface and the end of the pipe to the outside is provided on at least the inner periphery of the joint body between the contact surface and the lock ring. A joint fitted into the groove provided on the surface. 2. The pipe has a temperature of 85 ° C. and a pressure of 1.0 kgf /
when adding tensile load of mm ^2, the joint according to claim 1 elongation has a property of more than 20%. Wherein the pipe joint hands of claim 1 or claim 2 in which is formed of a polyolefin.