JP2002195480A - Joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint capable of making the manufacturing of a joint body easy, saving a production cost, and preventing the leakage of liquid from the joint. SOLUTION: The joint is mainly formed of the joint body 13 of an approximately cylindrical shape and an inner cylinder part 14 of an approximately cylindrical shape. A first female screw part 21 is threaded on the inner peripheral surface of the joint body 13. A third male screw part 30 is threaded on the base end part of the inner cylinder part 14, and the inner cylinder part 14 is fixed to the joint body 13 by screwing the third male screw part 30 into the first female screw part 21. An adhesive layer of anaerobic adhesive agent is interposed between the first female screw part 21 and the third male screw part 30. The insertion space of a circular shape for inserting a resin pipe 11 into the joint body 13 is formed between the inner peripheral surface of the joint body 13 and the outer peripheral surface of the inner cylinder part 14. A diameter reduced part 39 is formed in the inner depth part of the insertion space. One O-ring 40 is fitted into the diameter reduced part 39.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, this type of joint has a tubular shape, and mainly includes a joint body into which a resin pipe can be inserted, and an inner cylindrical portion into which an end of the resin pipe is inserted. . The inner cylinder is provided by integral molding with the joint body.

[0003]

However, in this conventional joint, since the joint body provided with the inner cylindrical portion has a complicated structure, it can be formed by cutting from a rod material, but it is not easy. In addition, it has been difficult to integrally manufacture the joint body by, for example, a casting method. For this reason, there has been a problem that the manufacturing cost increases.

[0004] In order to solve the above problems, it is conceivable to form the inner cylinder and the joint body separately and then attach the inner cylinder to the joint body. However, in the case of such a configuration, the liquid as the transport fluid flowing through the joint flows out between the inner peripheral surface of the joint main body and the outer peripheral surface of the inner cylinder portion, and leaks from the joint. There's a problem.

The present invention has been made by focusing on the problems existing in the prior art as described above. It is an object of the present invention to provide a joint capable of facilitating the manufacture of a joint main body, saving manufacturing costs, and preventing leakage of liquid from the joint.

[0006]

In order to achieve the above object, the joint according to the first aspect of the present invention has a tubular shape.
A joint body into which a resin pipe can be inserted, and formed separately from the joint body and attached inside the joint body,
An inner cylinder portion into which the end of the resin pipe is inserted, and in a state where the resin pipe is inserted into the joint body, between the outer peripheral surface on the base end side of the inner cylinder portion and the inner peripheral surface of the joint body, A seal member for sealing between the joint body, the inner cylinder and the resin pipe is provided.

[0007] In the joint according to the second aspect of the present invention, in the first aspect, a male screw portion is threaded on an outer peripheral surface of the inner cylindrical portion, and the male screw portion is formed on the inner peripheral surface of the joint body. By being screwed into the threaded female thread, the inner cylinder is attached to the joint body. Are fixed with an adhesive.

[0008] In the joint according to the third aspect of the present invention, in the invention according to the first or second aspect, the inner peripheral surface of the resin pipe insertion end of the joint main body increases in diameter toward the outer end. And a push ring screwed into the resin pipe insertion end of the joint body, and a tapered outer periphery interposed between the joint body and the push ring, corresponding to the taper surface. And a pressing ring for pressing the resin pipe in the insertion direction by screwing the pressing ring into the joint body.

In the joint according to a fourth aspect of the present invention, in the third aspect of the present invention, an accommodating groove is formed in the outer peripheral surface of the inner cylindrical portion, and an engaging convex portion is formed in the accommodating groove. When a plurality of resin pipes are provided and the resin pipe is inserted into the inner cylindrical portion, the distal end portion of the engagement convex portion is configured to regulate the protrusion from the outer peripheral surface of the inner cylindrical portion, and the push ring is connected to the joint. When the resin pipe is screwed into the main body, a tightening force is applied to the resin pipe, and when the resin pipe is prevented from falling into the joint main body, the inner peripheral surface of the resin pipe is pressed against the tip end of the engagement convex part. Are fitted.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 6, the resin pipe 11 is formed of a synthetic resin such as polyolefin (cross-linked polyethylene, polybutene, etc.) into a cylindrical shape, and is used for water supply piping and the like.

The joint 12 has a substantially cylindrical joint body 13.
, An inner cylindrical portion 14 having a substantially cylindrical shape, an annular pressing ring 15 having a portion cut away, and an annular washer 16.
And a push ring 17 composed of a nut. The joint body 13, the inner cylinder 14, the pressing ring 15, the washer 16, and the pressing ring 17 are formed of a metal material such as an alloy (brass, bronze, or the like).

As shown in FIG. 2 to FIG.
On the outer peripheral surface of the base end of the first threaded portion 18 is threaded,
It can be screwed into a pipe such as a water pipe. In addition, a contact surface 19 is provided in an annular shape on the inner peripheral surface at the central portion in the longitudinal direction of the joint body 13 so as to be orthogonal to the axis of the joint body 13.

An introduction path 20 is formed in the joint body 13 on the base end side of the contact surface 19 with the contact surface 19 as a boundary. When the joint body 13 is screwed into the pipe, the introduction path 20 allows a liquid as a transport fluid flowing through the joint 12 to flow. As shown in FIGS. 1A and 1B, the first female screw portion 2 is located closer to the resin pipe insertion end than the contact surface 19 on the inner peripheral surface of the joint body 13.
1 is threaded.

As shown in FIG. 2 to FIG.
A hexagonal nut-shaped first engagement portion 22 is formed on the outer peripheral surface at a substantially central portion in the longitudinal direction of the first portion. And the joint body 1
When screwing the tube 3 to the tube and releasing the tube, the joint main body 13 can be easily rotated by engaging a wrench or the like with the first engaging portion 22.

The first engaging portion 22 is formed with one through hole 23 having a substantially circular planar shape. A substantially cylindrical collar 24 made of a synthetic resin such as polyacetal is fitted into the through hole 23. A substantially cylindrical shaft 25 made of a synthetic resin such as polyacetal for visually confirming the insertion state of the resin pipe 11 into the joint body 13 is fitted into the collar 24. This shaft 2
5 is configured to be movable in a direction orthogonal to the axis of the joint body 13 in the through hole 23, and the outer end thereof is formed in the through hole 2.
3 and a position where the inner end protrudes into the joint body 13 from the through-hole 23 and a position where the outer end protrudes outward from the through-hole 23 and the inner end protrudes into the through-hole 23. The gap between them can be displaced according to the inserted state of the resin pipe 11.

A second external thread 27 is threaded on the outer peripheral surface of the resin pipe insertion end 26 of the joint body 13. In addition, an insertion hole 28 for inserting the resin pipe 11 is formed on the resin pipe insertion end side of the joint body 13.
On the inner peripheral surface of the opening of the insertion hole 28, a first tapered surface 29 whose diameter increases toward the outer end is formed.

As shown in FIGS. 1 (a), 1 (b) and 6, a third male screw portion 30 is provided at the base end of the inner cylindrical portion 14.
Is threaded, and can be screwed with the first female screw portion 21 of the joint body 13. Also, on the outer peripheral edge of the distal end of the inner cylindrical portion 14,
A second tapered surface 31 whose diameter decreases toward the distal end is formed, so that the end of the resin pipe 11 can be easily inserted into the inner cylindrical portion 14.

An accommodation groove 32 is formed in the outer peripheral surface on the distal end side of the inner cylinder portion 14 so as to be recessed over the entire outer periphery of the inner cylinder portion 14. As shown by the solid lines in FIGS.
A seal ring 33 made of a rubber material and having a circular cross section.
Are fitted. The outer diameter of the seal ring 33 is set so as to be the same length as the outer diameter of the inner cylindrical portion 14, that is, the thickness of the seal ring 33 is equal to the depth of the accommodation groove 32. And the resin pipe 11
When the end of the resin pipe 1 is inserted into the inner cylindrical portion 14,
One end face 34 is the tip 3 of each seal ring 33.
5, that is, not to come into contact with the outer peripheral portion of the seal ring 33.

As shown in FIGS. 1 (a) and 1 (b),
The inner cylindrical portion 14 has an end face 36 on the proximal end side thereof,
The third male screw portion 30 of the inner cylindrical portion 14 is screwed into the first female screw portion 21 of the joint body 13 until it comes into contact with the abutment surface 19 of the third body 3, thereby being fixed to the joint body 13. Further, the first female screw portion 21 of the joint body 13 and the inner cylindrical portion 1
Although not shown, an anaerobic for bonding and fixing between the first female screw part 21 of the joint body 13 and the third male screw part 30 of the inner cylinder part 14 is provided between the third male screw part 30 and the fourth male screw part 30. An adhesive layer made of the above adhesive is interposed. For this reason, the inner cylinder 1
4 is firmly fixed to the joint body 13. The adhesive layer is formed by immersing the proximal end of the inner cylindrical portion 14 in the adhesive up to the thread on the distal end side of the third male screw portion 30.

As shown in FIG. 3, between the inner peripheral surface of the insertion hole 28 and the outer peripheral surface of the inner cylindrical portion 14, an annular insertion space 37 for inserting the resin pipe 11 into the joint body 13 is provided. Are formed. Further, an inclined wall 38 whose diameter decreases toward the contact surface 19 is formed in the inner part of the insertion hole 28. Further, inside the inclined wall 38 of the insertion hole 28, the annular reduced diameter portion 3 whose outer diameter is smaller than the opening side of the insertion hole 28 is provided.
9 are formed. The reduced diameter portion 39 includes the joint body 1
3. One O-ring 40 having a circular cross section made of a rubber material is fitted as a seal member for sealing between the inner cylindrical portion 14 and the resin pipe 11. When the pressing ring 17 is tightened to the joint body 13, the end face 34 of the resin pipe 11 is pressed against the O-ring 40 so as to seal the space between the joint body 13, the inner cylindrical portion 14 and the resin pipe 11. Has become.

As shown in FIG. 2 to FIG.
A second female screw portion 41 is threaded on the inner peripheral surface of the base end portion 7 so that the second female screw portion 41 can be screwed with the second male screw portion 27 of the joint body 13. A hexagon nut-shaped second engagement portion 42 is formed on the entire outer circumference of the pressing ring 17. When the push ring 17 and the joint body 13 are screwed and released, the push ring 17 can be easily rotated by engaging a wrench or the like with the second engagement portion 42. Has become.

As shown in FIGS. 3 and 6, an insertion hole 43 is formed in the center of the distal end of the push ring 17 so as to penetrate the push ring 17. Further, a locking surface 44 is formed in an annular shape so as to be orthogonal to the axis of the push ring 17 on the tip side of the second female screw portion 41 inside the push ring 17. Push wheel 17
On the inner peripheral surface of the front end of the housing, a housing recess 45 is formed so as to be recessed over the entire circumference. In this accommodation recess 45, the resin pipe 1
An escape prevention ring 46 made of a rubber material and having a circular cross section for preventing the escape from the first joint 12 is fitted.

As shown in FIGS. 2 and 6, the pressing ring 15 is formed with a single slit extending in the axial direction, and can be advanced to the inner part by tightening the pressing ring 17 and can be reduced in diameter. Has become.

The outer peripheral surface of the pressing ring 15 is a third tapered surface 47 corresponding to the first tapered surface 29 of the joint body 13. On the other hand, on the inner peripheral surface of the pressing ring 15, an uneven surface for preventing the resin pipe 11 from falling into the joint body 13 is formed over the entire surface. The washer 1
6 is interposed between the pressing ring 15 and the locking surface 44 of the pressing ring 17.

Next, the operation of the joint 12 configured as described above will be described. When the resin pipe 11 is connected to the joint 12, first, the base end of the inner cylinder 14 is immersed in the adhesive up to the thread on the distal end side of the third external thread 30, and then the inner cylinder 14 is The proximal end surface 36 is the contact surface 1 of the joint body 13.
The third male screw portion 30 of the inner cylinder portion 14 is screwed into the first female screw portion 21 of the joint body 13 until the inner thread portion 9 comes into contact. Then O
After the ring 40 is fitted to the reduced diameter portion 39 in the joint body 13, the pressing ring 15 and the washer 16 are arranged on the resin pipe insertion end 26 of the joint body 13, and the pressing ring 17 is loosely screwed.

As shown in FIGS. 3 and 4, the end of the resin pipe 11 is inserted into the insertion space 37 in the joint body 13 through the insertion hole 43, and the end of the resin pipe 11 is Insert into. At this time, since the thickness of each seal ring 33 is the same length as the depth of the accommodation groove 32, the end face 34 of the resin pipe 11 does not abut on the distal end 35 of each seal ring 33, The end of the resin pipe 11 is smoothly inserted into the inner cylindrical portion 14.

When the end of the resin pipe 11 is inserted into the insertion space 37 in the joint body 13, the end of the resin pipe 11 is pressed against the inner end of the shaft 25, and the shaft 25 is moved to the outer periphery of the joint body 13. Moved towards the surface. As a result, the outer end of the shaft 25 is displaced from a state of being immersed in the through hole 23 to a state of protruding outward. Therefore, the insertion space 3 of the joint body 13 at the end of the resin pipe 11
7 can be visually recognized.

Next, as shown in FIG. 2, when the push ring 17 is tightened to the joint body 13 using a tool such as a spanner, the locking surface 44 of the push ring 17 is attached to the resin pipe insertion end 26 of the joint body 13. Due to the proximity, the pressing ring 15 is
Through the joint body 13. At this time, since the end of the resin pipe 11 is pressed in the entry direction, the end face 34 of the resin pipe 11 is pressed against the O-ring 40, and the space between the joint body 13, the inner cylinder 14 and the resin pipe 11 is sealed. .

Further, the third tapered surface 47 of the pressing ring 15 is engaged with the first tapered surface 29 of the joint body 13, and the diameter of the pressing ring 15 is reduced. As a result, the inner peripheral surface of the pressing ring 15 is pressed against and engaged with the outer peripheral surface of the resin pipe 11.
As a result, the resin pipe 11 is firmly prevented from falling into the joint body 13.

When the pressing ring 15 is pressed against and engaged with the outer peripheral surface of the resin pipe 11, the resin pipe 11
5 is pressed inward. For this reason, as shown by the two-dot chain line in FIG. 5, the inner peripheral surface of the resin pipe 11 presses the distal end portion 35 of each seal ring 33 and the gap between the outer peripheral surface of the inner cylindrical portion 14 and the resin pipe 11 is Sealed.

According to the above-described embodiment, the following effects can be obtained. -In the joint 12 of this embodiment, the joint main body 13 and the inner cylinder part 14 are formed separately. Therefore, the joint 12
Is easy to manufacture because of its simple configuration, and can save manufacturing costs.

In the joint 12 of the present embodiment, the proximal end face 36 of the inner cylindrical portion 14 is
The inner cylindrical portion 14 is screwed into the joint body 13 until the inner cylindrical portion 14 comes into contact with the joint 9. For this reason, an illusion of an operator can be prevented, and the inner cylinder portion 14 can be securely screwed to a predetermined position of the joint body 13.

In the joint 12 of the present embodiment, the third external thread 30 of the inner cylinder 14 is screwed into the first female thread 21 of the joint main body 13 so that the inner cylinder 14 is in the joint main body 13. Fixed. For this reason, when the resin pipe 11 inserted into the joint 12 is pulled out from the joint 12, the inner cylindrical portion 14 is moved together with the resin pipe 11 into the joint body 13.
It can be effectively prevented from being pulled out from the inside.

In the joint 12 of the present embodiment, an adhesive layer made of an anaerobic adhesive is interposed between the first female thread 21 of the joint body 13 and the third male thread 30 of the inner cylinder 14. Have been. Therefore, since the inner cylinder part 14 is firmly fixed to the joint main body 13, it is possible to prevent the screwing between the joint main body 13 and the inner cylinder part 14 from being loosened. For this reason, when connecting the resin pipe 11 to the joint 12,
It is not necessary to retighten, and the end of the resin pipe 11 can be fitted and inserted into the inner cylindrical portion 14 as it is, thereby facilitating the connection work. In addition, the liquid flowing through the joint 12 is connected to the first female thread portion 21 of the joint body 13 and the inner cylindrical portion 1.
4 from the third male screw portion 30 to the reduced diameter portion 39 in the joint body 13 can be prevented.

In the joint 12 of the present embodiment, one O-ring 40 is fitted to the reduced diameter portion 39 in the joint main body 13. When the push ring 17 is fastened to the joint body 13, the end surface 34 of the resin pipe 11 is
The O-ring 40 seals the space between the joint body 13, the inner cylindrical portion 14, and the resin pipe 11. For this reason, even if the liquid flows into the reduced diameter portion 39 in the joint main body 13 through the space between the first female screw portion 21 of the joint main body 13 and the third male screw portion 30 of the inner cylindrical portion 14, the liquid that has flowed in is made of resin. It can be prevented from flowing out between the outer peripheral surface of the pipe 11 and the inner peripheral surface of the joint body 13 and leaking out of the joint 12.

In the joint 12 of the present embodiment, four seal rings 33 are fitted in the accommodation grooves 32 as shown by the solid lines in FIG. When the pressing ring 15 is pressed against and engaged with the outer peripheral surface of the resin pipe 11, the resin pipe 11 is pressed inward by the pressing ring 15. For this reason, as shown by the two-dot chain line in FIG. 5, the inner peripheral surface of the resin pipe 11 presses the distal end portion 35 of each seal ring 33 and the gap between the outer peripheral surface of the inner cylindrical portion 14 and the resin pipe 11 is It is designed to be sealed.

When the pressure of the liquid flowing through the joint 12 is high, the second tapered surface 31 of the inner cylinder 14 and the resin pipe 1
The liquid flows into the storage groove 32 through the gap between the inner peripheral surface of the first groove and the inner peripheral surface of the first groove. For this reason, the seal ring 33 on the resin pipe insertion end side is used.
The liquid accumulates in the gap between the resin pipe 11 and the inner peripheral surface. Due to the pressure of the accumulated liquid, the adhesion between the seal ring 33 on the resin pipe insertion end side and the inner peripheral surface of the resin pipe 11 increases. Therefore, it is possible to prevent the liquid from flowing out between the seal ring 33 on the resin pipe insertion end side and the inner peripheral surface of the resin pipe 11.

Even if the liquid flows out between the seal ring 33 on the resin pipe insertion end side and the inner peripheral surface of the resin pipe 11, the liquid flows into the second seal ring 33 from the resin pipe insertion end side. It accumulates in the gap with the inner peripheral surface of the resin pipe 11. Due to the pressure of the accumulated liquid, the second seal ring 33 from the insertion end side of the resin pipe inserts the resin pipe 1
1, the adhesion between the second seal ring 33 from the resin pipe insertion end side and the inner peripheral surface of the resin pipe 11 is increased. Therefore, it is possible to prevent the liquid from flowing out between the second seal ring 33 from the resin pipe insertion end side and the inner peripheral surface of the resin pipe 11.

As described above, each seal ring 33
And the inner peripheral surface of the resin pipe 11 are increased by the pressure of the liquid flowing into the accommodating groove 32. Therefore, the liquid passes between the seal ring 33 and the inner peripheral surface of the resin pipe 11, and It can be prevented from flowing into the reduced diameter portion 39 in the inside 13.

In the joint 12 of the present embodiment, the thickness of the seal ring 33 is the same as the depth of the accommodation groove 32. For this reason, the end face 34 of the resin pipe 11 does not come into contact with the distal end 35 of the seal ring 33, and the end of the resin pipe 11 is easily fitted into the inner cylinder 14.

The above-described embodiment can be modified as follows. A plurality of O-rings 40 may be fitted to the reduced diameter portion 39. In the case of such a configuration, even if the liquid is supplied to the first internal thread portion 21 of the joint main body and the third external thread portion 3 of the inner cylindrical portion 14,
0, and flows into the reduced diameter portion 39 in the joint body 13 even if the respective seal rings 33 and the joint body 1
3. The adhesion between the inner cylindrical portion 14 and the resin pipe 11 is increased by the pressure of the liquid flowing into the reduced diameter portion 39. For this reason, it is possible to further prevent the flowing liquid from flowing out between the outer peripheral surface of the resin pipe 11 and the inner peripheral surface of the joint main body 13 and leaking out of the joint 12.

The number of the seal ring 33 may be changed to one. Alternatively, a seal ring having a rectangular cross section made of a rubber material and having a thickness set to be the same as the depth of the accommodation groove 32 may be used. Also in this case, the end face 34 of the resin pipe 11 does not come into contact with the tip 35 of the seal ring 33, and the end of the resin pipe 11 is
4 is easily inserted. Further, in the case of such a configuration, the liquid flowing in the joint 12 passes between the seal ring 33 and the inner peripheral surface of the resin pipe 11 and the joint body 13
There is a possibility of flowing into the reduced diameter portion 39 in the inside. However, even if the liquid flows between the seal ring 33 and the inner peripheral surface of the resin pipe 11 and flows into the reduced diameter portion 39 in the joint body 13, the O-ring 40 allows the joint body 13 and the inner cylindrical portion 14. In addition, since the space between the resin pipe 11 is sealed, it is possible to prevent the flowing liquid from flowing out between the outer peripheral surface of the resin pipe 11 and the inner peripheral surface of the joint body 13 and leaking out of the joint 12. it can.

The adhesive may be applied to the entire circumference of the first internal thread 21 of the joint body 13 or the third external thread 30 of the inner cylinder 14. Also, the adhesive is applied to the first body of the joint body 13.
In the female screw part 21 or the third male screw part 30 of the inner cylinder part 14, a line may be applied along the thread. Also,
The adhesive is applied to the first female screw portion 21 of the joint body 13 and the inner cylindrical portion 1.
You may apply | coat to both of the 3rd external thread part 30 of 4th. Also in this case, the inner cylindrical portion 14 is firmly fixed to the joint body 13 and the liquid flowing through the joint 12 is
The reduced diameter portion 3 in the joint body 13 passes between the first female thread portion 21 of the joint body 13 and the third male thread portion 30 of the inner cylinder portion 14.
9 can be prevented from flowing.

The adhesive may be changed to an adhesive sealing member. Also in this configuration, the inner cylinder portion 14 is firmly fixed to the joint body 13, and the liquid flowing through the joint 12 receives the first female screw portion 21 of the joint body 13 and the third It can be prevented from flowing into the reduced diameter portion 39 in the joint body 13 from between the external thread portion 30.

Next, the technical ideas that can be grasped from the above embodiment will be described below. The joint according to any one of claims 1 to 4, wherein the seal member is configured by an annular seal ring. According to this configuration, it is possible to easily seal the space between the joint body, the inner cylindrical portion, and the resin pipe, so that it is possible to prevent the liquid from leaking from the joint.

An inclined wall whose diameter is reduced toward the base end is formed on the inner peripheral surface of the joint body from the position where the seal member is provided to the insertion end side of the resin pipe. The joint according to claim 4. According to this configuration, when the end of the resin pipe is inserted into the joint main body, the end face of the resin pipe comes into contact with the end face of the inclined wall on the resin pipe insertion end side. When the push ring is fastened to the joint body, the resin pipe is pushed into the inner part while being held by the pressing ring. For this reason, the resin pipe can be prevented from falling into the joint body without resisting the tightening of the push ring.

The joint according to claim 4, wherein a plurality of the seal rings are fitted in the accommodation grooves. According to this configuration, when the high-pressure liquid flows through the joint, the adhesiveness between each seal ring and the inner peripheral surface of the resin pipe increases, so that the liquid flows between the seal ring and the inner peripheral surface of the resin pipe. It is possible to prevent the joint from leaking out from the joint.

[0048]

Since the present invention is configured as described above, it has the following effects. According to the joint according to the first aspect of the present invention, the manufacture of the joint main body can be facilitated, the manufacturing cost can be saved, and leakage of the liquid from the joint can be prevented.

According to the joint of the second aspect, in addition to the effect of the first aspect, the inner cylinder can be easily and securely attached to the joint body, and the outer periphery of the inner cylinder can be secured. It is possible to prevent the liquid from leaking from the joint by passing between the surface and the inner peripheral surface of the joint body.

According to the joint of the third aspect of the present invention, in addition to the effects of the first or second aspect of the present invention, the push ring is simply screwed into the resin pipe insertion end in the joint body. The liquid can be prevented from leaking out of the joint through the space between the inner peripheral surface of the joint body and the end surface of the resin pipe. Further, the resin pipe can be reliably prevented from falling into the joint body.

According to the joint of the invention described in claim 4, in addition to the effect of the invention described in claim 3, the end of the resin pipe can be connected to the inner cylindrical portion without causing any trouble such as damage to the seal member. The fitting can be smoothly performed, and the leakage of the liquid from the joint can be prevented even when the pressure of the liquid as the transport fluid is high.

[Brief description of the drawings]

FIG. 1A is an enlarged cross-sectional view of a main part showing a state before an inner cylindrical portion is screwed to a joint main body in the present embodiment. (B)
FIG. 4 is an enlarged sectional view of a main part showing a state after the inner cylindrical portion is screwed into the joint body.

FIG. 2 is a semi-longitudinal sectional view showing a state after a pressing ring is fastened to a joint body.

FIG. 3 is a partially broken side view showing a state before a resin pipe is inserted into a joint.

FIG. 4 is a semi-longitudinal sectional view showing a state before the pressing ring is fastened to the joint body.

FIG. 5 is an essential part cross-sectional view showing a seal member.

FIG. 6 is an exploded perspective view showing a joint.

[Explanation of symbols]

11 ... resin pipe, 13 ... joint body, 14 ... inner cylinder part, 1
5 ... Pressing ring, 17 ... Pressing ring, 21 ... First female screw part as female screw part, 26 ... Resin pipe insertion end part, 29 ... First taper surface as taper surface, 30 ... Third male screw part as male screw part , 32 ... accommodation groove, 33 ... seal ring, 3
5: Tip, 40: O-ring as seal member, 47
... A third tapered surface as a tapered outer peripheral surface.

Claims (4)

[Claims] 1. A joint body having a tubular shape into which a resin pipe can be inserted, and an inner cylinder formed separately from the joint body and mounted in the joint body and into which an end of the resin pipe is inserted. Between the joint body, the inner cylinder part and the resin pipe, between the outer peripheral surface on the base end side of the inner cylinder part and the inner peripheral surface of the joint body when the resin pipe is inserted into the joint body. A seal member for sealing the joint. 2. An inner thread portion is threaded on an outer peripheral surface of the inner cylinder portion, and the outer thread portion is screwed into a female thread portion threaded on an inner peripheral surface of the joint body. 2. The joint according to claim 1, wherein the joint is attached to the main body, and between the female thread of the joint main body and the male thread of the inner cylinder is fixed with an adhesive when the joint main body and the inner cylinder are screwed together. 3. 3. The inner peripheral surface of the resin pipe insertion end of the joint main body is screwed to a tapered surface formed to increase in diameter toward the outer end, and to the resin pipe insertion end of the joint main body. Push ring, and is interposed between the joint body and the push ring, and has a tapered outer peripheral surface corresponding to the tapered surface,
The joint according to claim 1, further comprising: a pressing ring that presses the resin pipe in the insertion direction by screwing the pressing ring into the joint main body. 4. An accommodation groove is formed in the outer peripheral surface of the inner cylinder portion, and a plurality of engaging projections are provided in the accommodation groove, and a resin pipe is fitted into the inner cylinder portion. Sometimes
The distal end of the engaging projection is configured to regulate the protrusion of the inner cylindrical portion from the outer peripheral surface. By screwing the push ring into the joint body, a tightening force is applied to the resin pipe, and 4. An annular seal ring, which is configured so that the inner peripheral surface of the resin pipe is pressed against the distal end portion of the engaging projection when the is prevented from falling into the joint body.
The joint described in the above.