JP2001021075A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint having an inner core which can be simply fitted in a fluid pipe. SOLUTION: An inner core 8 is formed in a cylindrical shape, having a thin wall thickness, and is formed with gaps at predetermined intervals in the circumferential direction. Further, the diameter thereof can be resiliently decreased in the diametrical direction. Since the gaps are formed in the circumferential direction in the inner core 8, it can be inserted in a fluid pipe 2 by decreasing its diameter. Thus, the resistance during the insertion is small, and accordingly, the fitting thereof can be facilitated, thereby it is possible to shorten the working time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint used for connecting a water pipe, a gas pipe, and a pipe for a plant made of a soft synthetic resin such as polyethylene.

[0002]

2. Description of the Related Art Conventionally, as a pipe joint of this kind, a pipe joint disclosed in Japanese Patent Laid-Open No. 10-122559 has been known. (FIG. 6)

[0003] This conventional pipe joint A comprises a joint body B, a fluid pipe C and an in-core D.
A packing housing B2 is formed near the opening end of the first housing 1, and a ring housing B3 having a substantially U-shaped cross section is formed at the back of the packing housing B2.

[0004] The packing E is inserted into the packing accommodating portion B2.
Is inserted, and the insertion portion C1 of the fluid pipe C is inserted into the receiving portion B1 in a state where the centering member F and the separation preventing ring G are stored in the ring storage portion B3.

An in-core D having an outer diameter slightly larger than the inner diameter of the insertion portion C1 is inserted into the insertion portion C1 in order to prevent the insertion portion C1 from being detached from the insertion portion C1.

[0006] The in-core D is mounted to prevent deformation of the insertion portion C1 to which a force in the diameter reducing direction is applied by the packing E and the separation prevention ring G.

The fluid pipe C to which the incore D is mounted is:
Flexible synthetic resin pipes such as polyethylene pipes, with large variations in pipe diameter and pipe thickness due to the manufacturing method and characteristics of the materials, and the pipe diameter and pipe thickness in each standard for soft synthetic resin pipes have a large tolerance. I have.

[0008]

The in-core in such a conventional pipe joint is formed to have an outer diameter larger than the maximum inner diameter of the fluid pipe in consideration of a tolerance in order to prevent the in-core from coming out of the mounted fluid pipe. I was

Therefore, at the time of joining the fluid pipes, an incore having an outer diameter larger than the inner diameter of the fluid pipe is inserted into the inner peripheral portion of the fluid pipe, and the incore is inserted so as to expand the fluid pipe. Therefore, a large force is required to mount the incore, and it is hit with a hammer, it comes out due to the repulsive force of the fluid pipe, it is difficult to mount it in a predetermined position, and the working time is shortened. I needed a lot.

The problem to be solved by the present invention has been made to solve the above problems, and an object of the present invention is to provide an in-core pipe joint which can be easily attached to a fluid pipe.

[0011]

In order to solve the above-mentioned problems, a pipe joint according to the present invention comprises a fluid pipe having an incore fitted on an inner peripheral surface of an end portion thereof, and a fluid pipe provided in a receiving portion provided with packing. A pipe joint comprising an end portion of a pipe and a joint body inserted in a watertight manner, wherein the incore is formed in a thin cylindrical shape, a gap is provided in a circumferential direction at a predetermined interval, and the incore is elastically compressed in a radial direction. The feature is that the diameter can be adjusted. Due to this feature, since a gap is provided in the incore in the circumferential direction, it can be inserted with a reduced diameter when mounted on the fluid pipe. Therefore, since the resistance at the time of insertion is small, mounting is easy and the working time is shortened. Further, since the in-core is elastically reduced in diameter, it is restored after the mounting, and is pressed against the inner peripheral surface of the fluid pipe, so that the in-core is prevented from coming out of the fluid pipe, and the mounting position is held and stably fixed.

Preferably, the incore is provided with a regulating device for regulating the diameter reduction. In this way, when a force in the diameter reducing direction acts on the fluid pipe, the incore is reduced to a predetermined diameter, but the diameter reduction is regulated by the regulating device. It is possible to prevent the tube from being reduced in diameter.

[0013] In the in-core regulating device, it is preferable that a locking portion is provided at one end in the circumferential direction so that the other end thereof abuts to restrict the diameter reduction. With this configuration, the locking portion is provided at one end in the circumferential direction of the in-core, and the other end abuts on the locking portion, so that the diameter reduction is regulated and further deformation is reliably prevented.

[0014] It is preferable that the in-core regulating device is provided with a blocking portion for preventing the ends in the circumferential direction from overlapping with each other. By doing so, the overlapping of the circumferential ends can be prevented by the blocking portion, so that the diameter reduction of the in-core can be reliably prevented.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a first embodiment in which fluid pipes 2 and 2 made of polyethylene are joined using a pipe joint 1 of the present invention.

In the same figure, 3 is a joint body made of ductile cast iron, 4 is a pressing ring fastened to the joint body 3, and 5 is
A lock ring 6 disposed on the inner peripheral surface of the press ring 4 is a packing for joining the fluid pipe 2 to the joint body 3 in a watertight manner, 7 is a retainer for pressing the packing 6, and 8 is an inner peripheral end of the fluid pipe 2. It is an in-core attached to.

At the center of the inner surface of the joint body 3, there is provided a stopper 3d protruding in the center direction, and at both ends of the joint body 3, there are formed enlarged diameter portions 3a for accommodating the packing 6,
A flange 3b is continuously provided on its outer surface, and the enlarged diameter portion 3 is formed.
An abutting portion 3c for preventing the retainer 7 from abutting on the end portion a is provided at an end of the a.

A flange 4b of the pressing ring 4 is provided with a plurality of T-head bolts 1 on a flange 3b provided on the outer peripheral surface of the joint body 3.
5 and the nut 16
Are tightened by the inner tapered surface 4a of the pressing wheel 4.

The lock ring 5 has a split shape formed of a synthetic resin harder than the fluid pipe 2, for example, a metal body such as acetal resin or stainless steel, and returns to its original shape even if the diameter is reduced. It has elasticity, and its outer peripheral surface has an outer tapered surface 5 whose inclination is substantially the same as that of the inner tapered surface 4a of the pressing ring 4.
is formed, the maximum outer diameter thereof is set to be larger than the maximum inner diameter of the inner tapered surface, and a plurality of blades 5b facing the circumferential direction are formed on the inner peripheral surface.

As shown in FIG. 3, the in-core 8 has a body 8a formed in a thin cylindrical shape whose outer diameter in a natural state is slightly larger than the inner diameter of the fluid pipe 2, and has an outer radial direction at one end. And a small-diameter portion 8c at the other end, the outer diameter of which gradually decreases. The in-core 8 is cut in the circumferential direction, end portions 8d and 8e are provided at predetermined intervals, and a gap 8f is formed. Also, it has elasticity to return to the original state even when the diameter is reduced.

Using the pipe joint 1 of the above embodiment, a fluid pipe 2
First, the incore 8 is inserted until the flange 8b comes into contact with the end of the fluid pipe 2 to be joined.

Next, a T-head bolt 15 is inserted into the flange 3b and the flange 4b, and the nut 16 is temporarily tightened. The pressing ring 4 in which the lock ring 5 and the retainer 7 are mounted is mounted on the expanded portion 3a by the packing 6. Temporarily fix to the inserted joint body 3.

Next, the fluid pipe 2 in which the in-core 8 is mounted is inserted from the end of the press ring 4 temporarily fixed to the joint body 3 until it comes into contact with the stopper 3c, and the nut 16 temporarily tightened is connected to the flange 3b. The flanges 4b are evenly tightened until they come into contact with each other to complete the joining.

When the incore 8 is attached to the end of the fluid pipe 2, a force is applied to the incore 8 in which the gap 8f is formed so that the diameter can be reduced and the incore 8 can be inserted into the fluid pipe 2. Work can be performed and work time can be reduced.

Further, since the in-core 8 has elasticity, the diameter of the in-core 8 expands and adheres to the inner peripheral surface of the fluid pipe 2 when the force for reducing the diameter is removed, so that the in-core 8 does not fall off from the fluid pipe 8 and is stable. It can be attached to the target.

FIG. 4 shows an in-core 9 according to a second embodiment of the present invention.
The joint body 3, the press wheel 4, the lock ring 5, the packing 6, the retainer 7 and the like are configured in substantially the same manner as in the first embodiment, and are used in a pipe joint.

The in-core 9 is formed in a thin cylindrical shape whose outer diameter in a natural state is slightly larger than the inner diameter of the fluid pipe 2, is cut in the circumferential direction, and is provided with ends 9a and 9b and shrinks. It has the elasticity to return to the original state even if the diameter is changed.

At one end 9a, a regulating device 13 formed in a substantially L shape by a locking portion 9c and a blocking portion 9d projecting in the center direction is provided at three places at a predetermined interval. The end 9b is fitted between the end 9a and the regulating device 13.

The connection of the fluid pipe 2 with the pipe joint 1 using the in-core 9 of the second embodiment is performed in the same manner as in the first embodiment.

When attaching the incore 9 to the end of the fluid pipe 2, the diameter can be reduced until the end 9b abuts on the locking portion 9c and the fluid can be inserted into the fluid pipe 2, so that the work can be easily performed. Work time can be shortened.

Further, since the in-core 9 has elasticity, the diameter of the in-core 9 expands and becomes in close contact with the inner peripheral surface of the fluid pipe 2 when the force for reducing the diameter is removed, so that the in-core 9 does not fall off from the fluid pipe 2 and is stable. It can be attached to the target.

When the fluid pipe 2 and the joint body 3 move relatively to each other and the lock ring 5 is reduced in diameter, and a force in the diameter reducing direction acts on the fluid pipe 2, the incore 9 is attached to the locking portion 9 a at the end 9 b. Abuts the diameter of the fluid pipe 2 to prevent the diameter of the fluid pipe 2 from being reduced. Further, the stopper 9c prevents the end 9b from moving toward the center of the diameter, thereby preventing the fluid pipe 2 from being reduced in diameter.

FIG. 5 shows an in-core 1 according to a third embodiment of the present invention.
0, the joint body 3, the press ring 4, the lock ring 5, the packing 6, the retainer 7, etc. are configured in substantially the same manner as in the first embodiment and are used in a pipe joint.

The in-core 10 is cut in the circumferential direction, and ends 10a and 10b are provided at predetermined intervals.
0c is formed, and it has elasticity to return to the original state even if the diameter is reduced.

The gap 10c is provided with an engaging portion 11 which contacts the ends 10a and 10b to regulate the diameter of the gap 10c, and an end 10a and 10b.
A restricting device 14 having a substantially H-shaped cross section is fitted with the blocking portions 12 and 12 for preventing b from moving in the center direction and the opposite center direction.

The connection of the fluid pipe 2 with the pipe joint 1 using the in-core 10 of the third embodiment is performed in the same manner as in the first embodiment.

When the in-core 10 is mounted on the end of the fluid pipe 2, the diameter is reduced until the ends 10a and 10b abut on the locking portion 11, and the diameter is smaller than the inner diameter of the fluid pipe 2. Therefore, the work can be easily performed and the work time can be reduced.

Further, since the in-core 10 has elasticity, the diameter of the in-core 10 expands and becomes in close contact with the inner peripheral surface of the fluid pipe 2 without removing the force that reduced the diameter. It is easy to determine the mounting position, and stable mounting can be performed.

When the fluid pipe 2 and the joint body 3 move relatively to each other, and the lock ring 5 is reduced in diameter, and a force in the diameter reducing direction acts on the fluid pipe 2, the incore 10 is attached to the locking portion 11 by the end 10 a. , 1
The diameter of the fluid pipe 2 is prevented by the contact of Ob. In addition, the stoppers 12 prevent the ends 10a and 10b from moving toward the center of the diameter, thereby preventing the fluid pipe 2 from being reduced in diameter.

Although the embodiment of the present invention has been described with reference to the drawings, the specific configuration of the present invention is not limited to this.

In the embodiment, the fitting is provided with the push ring and the lock ring, but may be an insertion type fitting without the push ring and the lock ring.

[0042]

According to the present invention, since the in-core is provided with a gap in the circumferential direction, it can be inserted with a reduced diameter when mounted on the fluid pipe, so that the resistance at the time of insertion is small. And the work time is shortened. Also, since the incore is elastically reduced in diameter, it will be restored after mounting,
Since it comes into pressure contact with the inner peripheral surface of the fluid pipe, it is prevented from falling out of the fluid pipe, and the mounting position is held and stably fixed.

According to the second aspect of the present invention, when a force in the diameter reducing direction acts on the fluid pipe, the diameter of the incore is reduced to a predetermined diameter. And the diameter of the fluid pipe can be prevented from being reduced.

According to the third aspect of the present invention, the locking portion is provided at one end in the circumferential direction of the incore, and the other end contacts the locking portion, so that the diameter reduction is regulated and further deformation is reliably prevented. Is done.

According to the fourth aspect of the present invention, the overlapping of the ends in the circumferential direction can be prevented by the blocking portion, so that the diameter reduction of the in-core can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is also a side view.

3 (a) is a front view and FIG. 3 (b) is a side view of the incore.

FIG. 4 is an in-core of the second embodiment of the present invention, wherein (a)
Is a front view, (b) is a side view, and (c) is a 1-1 cross-sectional view.

FIG. 5 is an in-core of a third embodiment of the present invention, wherein (a)
Is a front view, (b) is a side view, and (c) is a side view of the regulating device.

FIG. 6 is a sectional view a showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe joint 2 Fluid pipe 3 Joint main body 3a Enlarged diameter part 3b Flange 3c Contact part 3d Stopper 4 Press ring 4a Inner taper surface 4b Flange 5 Lock ring 5a Outer taper surface 5b Blade 6 Packing 7 Retainer 8 In-core 8a Body 8b Collar 8 Small-diameter portion 8d, 8e End 8f Gap 9 In-core 9a, 9b End 9c Locking portion 9d Inhibitor 10 In-core 10a, 10b End 10c Gap 11 Locking portion 12 Blocking portion 13, 14 Regulator 15 T head bolt 16 Nut

Claims (4)

[Claims] 1. A pipe joint comprising: a fluid pipe having an incore fitted to an inner peripheral surface of an end thereof; and a joint body having an end of the fluid pipe inserted into a receiving portion provided with packing in a watertight manner. The pipe joint, wherein the incore is formed in a thin cylindrical shape, a gap is provided in a circumferential direction at a predetermined interval, and the diameter of the incore can be elastically reduced in a radial direction. 2. The pipe joint according to claim 1, wherein the in-core is provided with a restricting device for restricting a diameter reduction. 3. The pipe joint according to claim 2, wherein the in-core restricting device is provided with a locking portion at one end in a circumferential direction, the locking portion being in contact with the other end to restrict the diameter reduction. 4. The pipe joint according to claim 2, wherein said in-core regulating device is provided with a blocking portion for preventing overlapping of circumferential ends.