JP2003240169A - Pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe joint connectable to a corrugated pipe with a high sealability. <P>SOLUTION: When a bag nut 12 screwed to a pipe connecting part 17 of a joint body 11 is clamped, a retainer 13 presses an end of a bellows pipe 16 deeply into the pipe connecting part 17, thereby pressing the end surface of the end of the bellows pipe 16 to a flat packing 14. Simultaneously, the end of the bellows pipe 16 is crushed between the flat packing 14 and the retainer 13, thereby pressing the outer periphery of the end of the bellows pipe 16 to an O-ring 15. <P>COPYRIGHT: (C)2003,JPO

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 a corrugated pipe used in a water supply / hot water supply piping system.

[0002]

2. Description of the Related Art As a pipe joint used by connecting to a corrugated pipe, for example, one disclosed in JP-A-62-20292 is known. In the pipe joint described in the publication, a corrugated pipe having a retaining ring mounted on the outer peripheral portion is inserted into the pipe connecting portion of the joint body, and then the cap nut is tightened to the pipe connecting portion. Then, the retaining ring pushes the end of the corrugated pipe into the inner part of the joint body by the cap nut, and as a result, the end of the corrugated pipe is crushed between the step and the retainer in the joint body, and The outer circumference of the end of the pipe is pressed against the O-ring so that the outer circumference of the end of the corrugated pipe is sealed to the joint body.

[0003]

However, in the pipe joint described in the above publication, the seal at the connecting portion with the corrugated pipe is almost solely handled by the O-ring. For this reason, there is no particular problem in using as a pipe joint for gas pipes with low fluid pressure, but there is a problem that satisfactory sealing performance is not always obtained as a pipe joint for water supply / hot water supply pipes with high fluid pressure. It was

The present invention has been made by paying attention to the problems existing in the prior art as described above. It is an object of the present invention to provide a pipe joint that can be connected to a corrugated pipe with high sealing properties and can be suitably used in a water supply / hot water supply piping system.

[0005]

In order to achieve the above object, the invention as set forth in claim 1 is a pipe joint used by connecting to a corrugated pipe, wherein the corrugated pipe is inserted. A joint main body having a permissible pipe connecting portion, a screwing member screwed to the pipe connecting portion of the joint main body along its axial direction, and an outer circumference of a corrugated pipe inserted into the pipe connecting portion of the joint main body. And a first seal ring that seals between the end face of the same corrugated pipe and the joint body, and a seal between the outer periphery of the end of the same corrugated pipe and the joint body. And a second seal ring, and the corrugated pipe having the retainer mounted on the outer peripheral portion is inserted into the pipe connecting portion of the joint body, and then the screwing member is screwed into the pipe connecting portion and tightened. And the retainer pushes the end of the corrugated pipe into the inner part of the pipe connecting portion by the screwing member. As a result, the end face of the corrugated pipe is pressed against the first seal ring, and at the same time, the end portion of the corrugated pipe is crushed between the first seal ring and the retainer to form the same corrugated pipe. The gist is that the outer circumference of the end portion of the tube is pressed against the second seal ring.

According to a second aspect of the present invention, in the pipe joint according to the first aspect, the second seal ring is configured to engage with the first seal ring, and the first seal ring is engaged with the first seal ring. The gist is that the seal ring is retained in the joint body.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is embodied in a pipe joint used by connecting to a bellows pipe (made of metal) which is a type of corrugated pipe will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the pipe joint of the present embodiment includes a joint body 11 and a cap nut 1 as a screw member.
2, retainer 13, flat packing 14 as a first seal ring, and O-ring 1 as a second seal ring
It is composed of 5.

The joint body 11 has a substantially cylindrical shape, and a pipe connecting portion 17 which allows the bellows pipe 16 to be inserted is formed at one end (the right end in FIG. 1). A screw thread 18 is formed on the outer peripheral surface of the pipe connecting portion 17, and the cap nut 12 is screwed onto the pipe connecting portion 17 along the axial direction thereof. As shown in FIG. 3, the inner peripheral surface of the pipe connecting portion 17 is formed so that circular arc surfaces S1 and flat surfaces S2 are alternately continuous in the circumferential direction.

The retainer 13 is composed of two split rings 13a each having a substantially semi-cylindrical shape, and is attached to the outer peripheral portion of the bellows pipe 16 while facing it. The inner peripheral surface of the retainer 13 is formed in a corrugated shape corresponding to the outer peripheral shape of the bellows pipe 16. On the other hand, the shape of the outer peripheral surface of the retainer 13 corresponds to the shape of the inner peripheral surface of the pipe connecting portion 17, and is formed such that the circular arc surface S1 and the flat surface S2 are alternately continuous in the circumferential direction as shown in FIG. Has been done. The axial length of the retainer 13 corresponds to two peaks on the outer circumference of the bellows pipe 16. The two split rings 13a are originally integrally connected by the thin portion 19 and are divided into two when used.

The flat packing 14 is disposed on an annular step surface 20 provided in the inner peripheral portion of the joint main body 11 in the axial direction and inward of the pipe connecting portion 17. The step surface 20 faces the pipe connecting portion 17 side. Since the end of the bellows pipe 16 is strongly pressed against the flat packing 14 when the bellows pipe 16 is connected to the pipe joint, the flat packing 14 preferably has high mechanical strength. Specifically, the flat packing 14 is preferably made of synthetic resin containing a reinforcing material such as aramid fiber or inorganic fiber.

On the other hand, the O-ring 15 is disposed in an annular receiving groove 21 provided in the inner peripheral portion of the joint body 11 on the pipe connecting portion 17 side with respect to the step surface 20 in the middle of the joint body 11 in the axial direction. . The O-ring 15 engages with the flat packing 14, and the flat packing 14 is held in the joint body 11 by this engagement relationship.

Next, the operation of the pipe joint constructed as described above will be described. When connecting the bellows pipe 16 to the pipe joint of the present embodiment, first, the retainer 13 is attached to the outer peripheral portion of the bellows pipe 16 while being attached thereto. When attaching the retainer 13 to the outer peripheral portion of the bellows pipe 16, the bellows pipe 1
One peak of the outer circumference of the bellows tube 16 is left at the end of 6 (see FIG. 1A).

Subsequently, as shown in FIG. 1 (a), a bellows pipe 16 having a retainer 13 mounted on the outer peripheral portion thereof is attached to a joint body 1
1 into the pipe connection portion 17, and the pipe connection portion 17 with the cap nut 1
Screw 2 on. When the cap nut 12 is tightened in this state, the retainer 13 pushes the end portion of the bellows pipe 16 into the inner part of the pipe connection portion by the cap nut 12 as shown in FIG. End packing is flat packing 1
As a result of being pressed against 4, the end face of the bellows pipe 16 and the joint body 11 are sealed. At the same time, the end portion of the bellows pipe 16 is crushed between the flat packing 14 and the retainer 13 and the outer periphery of the end portion of the bellows pipe 16 is pressed against the O-ring 15. As a result, the outer periphery of the end portion of the bellows pipe 16 and the joint body The space between 11 and 11 is sealed.

The effects obtained by this embodiment will be described below. The bellows pipe 16 connected to the pipe joint is not only sealed by the O-ring 15 at the outer periphery of the end portion but also by the flat packing 14 at the end face of the end portion. Therefore, according to the pipe joint of the present embodiment, the pipe joint can be connected to the bellows pipe 16 with a higher sealing property than that of the conventional pipe joint, and can be suitably used in a water supply / hot water supply piping system.

The O-ring 15 not only plays a part of sealing the bellows pipe 16 with respect to the joint body 11, but also plays a role of preventing the flat packing 14 from falling off. Therefore, the structure that prevents the flat packing 14 from falling
Since it is not necessary to additionally provide the ring 15 separately, the structure of the pipe joint can be simplified.

If the flat packing 14 is made of synthetic resin mixed with a reinforcing material such as aramid fiber or inorganic fiber, the mechanical strength of the flat packing 14 can be increased and the end of the bellows pipe 16 can be increased. It is possible to prevent the flat packing 14 from being damaged when the portion is strongly pressed.

The retainer 13 has an axial length corresponding to two peaks on the outer circumference of the bellows pipe 16. Therefore, as compared with a retainer having an axial length corresponding to one mountain on the outer circumference of the bellows pipe 16, the retainer 13 can reliably hold the bellows pipe 16.
Further, compared with a retainer having an axial length corresponding to three or more peaks on the outer circumference of the bellows pipe 16, the axial lengths of the cap nut 12 and the pipe connecting portion 17 can be shortened, so that the pipe joint It can be made compact.

The above embodiment may be modified as follows. In the above embodiment, the present invention is embodied in a pipe joint used by connecting to a bellows pipe, but it may be embodied in a pipe joint used by connecting to a spiral pipe which is one of the same corrugated pipes. .

The shape of the inner peripheral surface of the pipe connecting portion 17 and the shape of the outer peripheral surface of the retainer 13 may be any shape as long as the retainer 13 does not rotate with the rotation of the cap nut 12, and may be appropriately changed. You may comprise.

When attaching the retainer 13 to the outer peripheral portion of the bellows pipe 16, two or more peaks on the outer periphery of the bellows pipe 16 may be left at the end of the bellows pipe 16. However, in that case, it is necessary to lengthen the axial length of the cap nut 12 or the pipe connection portion 17 so as to correspond thereto.

The axial length of the retainer 13 may be changed so as to correspond to one mountain or three or more mountains on the outer circumference of the bellows pipe 16. However, in that case, it is necessary to lengthen the axial length of the cap nut 12 or the pipe connection portion 17 so as to correspond thereto.

The O-ring 15 in the above embodiment may be changed to a square ring. Next, technical ideas that can be understood from the above-described embodiment will be described below. The pipe joint according to claim 1 or 2, wherein a reinforcing material such as an aramid fiber or an inorganic fiber is mixed as the first seal ring. According to this structure, the mechanical strength of the first seal ring can be increased, and the first seal ring can be prevented from being damaged when the end portion of the corrugated pipe is pressed. .

The retainer is attached to the outer peripheral portion of the corrugated pipe such that one peak of the outer periphery of the corrugated pipe is left at the end portion of the corrugated pipe. Item 2
The pipe fitting described in. With this configuration, the axial lengths of the threaded member and the pipe connecting portion can be shortened, and the pipe joint can be made compact.

The pipe joint according to claim 1 or 2, wherein the axial length of the retainer corresponds to two peaks on the outer circumference of the corrugated pipe. According to this structure, the corrugated pipe can be reliably gripped by the retainer, and at the same time, the pipe joint can be made compact.

[0026]

Since the present invention is constructed as described above, it has the following effects. According to the invention described in claim 1, the corrugated pipe can be connected with a high sealing property, and can be suitably used in a piping system of a water supply / hot water supply system.

According to the invention of claim 2, claim 1
In addition to the effect of the invention described in (1), the structure can be simplified.

[Brief description of drawings]

1A and 1B are half cross-sectional views showing a usage state of a pipe joint according to an embodiment.

FIG. 2 is an exploded perspective view of the pipe joint.

FIG. 3 is a front view of the joint body as viewed from the pipe connection portion side.

FIG. 4 is a front view showing the retainer in a state where two split rings are connected to each other.

[Explanation of symbols]

11 ... Joint body, 12 ... Cap nut as screwing member, 1
3 ... Retainer, 14 ... Flat packing as first seal ring, 15 ... O-ring as second seal ring,
16 ... Bellows pipe as corrugated pipe, 17 ... Pipe connecting portion.

Claims (2)

[Claims] 1. A pipe joint used by connecting to a corrugated pipe, the joint main body having a pipe connecting portion that allows insertion of the corrugated pipe, and an axial direction of the pipe connecting portion of the joint main body. A threaded member that is screwed along, a retainer that is attached to the outer peripheral portion of the corrugated pipe that is inserted into the pipe connection portion of the joint body, and an end face of the corrugated pipe and the joint body. A corrugated pipe provided with a first seal ring for sealing the space and a second seal ring for sealing between the outer periphery of the end portion of the corrugated pipe and the joint body, and the retainer mounted on the outer peripheral portion. When the screwing member is screwed and tightened to the pipe connecting portion after inserting the pipe into the pipe connecting portion of the joint body, the retainer causes the retainer to connect the end portion of the corrugated pipe to the pipe connecting portion. As a result of being pushed inward, the end face of the corrugated pipe is pressed against the first seal ring. At the same time, the end portion of the corrugated pipe is crushed between the first seal ring and the retainer, and the outer periphery of the end portion of the corrugated pipe is pressed against the second seal ring. Pipe fittings. 2. The second seal ring is configured to engage with the first seal ring, and the engagement relationship allows the first seal ring to engage with the first seal ring.
2. The pipe joint according to claim 1, wherein the seal ring is held in the joint body.