JP2008163981A - Connecting structure of pipe and pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting structure of a pipe and a pipe joint, which provides a stable locking effect when connecting a composite pipe. <P>SOLUTION: The connecting structure is provided with: a caulking ring 12 fitted into a cap nut from a female screw 22 side of the cap nut 6, straddling a tapered surface 25 and an annular inner peripheral surface 23, and arranged in such a state that a top end outer peripheral surface 12a is brought in contact with the tapered surface 25; a support ring 13 arranged in the annular inner peripheral surface 23 to support the caulking ring 12; and a pawled ring 14 arranged in the annular inner peripheral surface 23 to be brought in contact with the outer peripheral surface 1a of the pipe 1 inserted into an annular groove 9. The composite pipe having at least three-layer structure in which a metal layer 4 made of a metal material is sandwiched between synthetic resin layers made of a synthetic resin material is used as the pipe 1. The metal outer peripheral surface of the metal layer 4 of the pipe 1 is reduced in diameter by compressing with a caulking pawl 15 installed in the caulking ring 12. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a connection structure between a pipe and a joint.

  At the time of plumbing for water supply and hot water supply, draw the water supply main pipe and the hot water supply main pipe from the hot water supply equipment indoors, and connect the water supply main pipe and the hot water supply main pipe to the water supply pipe header and the hot water supply pipe header, As a water supply pipe or hot water supply pipe that connects each of these headers with, for example, a water stop cock located upstream of a hot water mixing tap in a bathroom, it is resistant to heat such as cross-linked polyethylene, is not easily deformed, and does not rust. It is used by inserting a resin pipe with excellent durability into the bellows-shaped sheath tube, so that in the case of water leakage etc., the sheath tube is left as it is and both ends of the resin pipe are connected It is convenient in that the resin pipe can be taken out and replaced from the inside of the sheath tube simply by releasing the.

  The joint described in the following Patent Document 1 is of a type that seals between the outer peripheral surface of the inner cylinder portion of the joint body and the inner peripheral surface of the resin pipe, in order to prevent the resin pipe from coming off from the joint body. The retaining member is provided with a regulating piece having a rounded tip, and is connected so as to bite into the outer peripheral portion of the resin pipe.

JP 2001-254884 A

  By the way, in recent years, in addition to the resin pipe, a composite pipe having, for example, a three-layer structure made of a synthetic resin material such as cross-linked polyethylene and a metal material such as aluminum and having an aluminum metal layer sandwiched between synthetic resin layers has been used. Assuming that the composite pipe is connected to the joint, in the retaining member having a regulating piece with a rounded tip, the synthetic resin layer on the outermost periphery of the composite pipe is as shown in the drawings described later. In addition, since it is thin, there is a possibility that a stable retaining effect cannot be obtained.

  It is an object of the present invention to provide a pipe-joint connection structure that can provide a stable retaining effect when connecting composite pipes.

To achieve the above object, the pipe and joint connection structure of the present invention is a pipe configured to connect a pipe and a joint by inserting the pipe into a joint in a pre-assembled state without tightening the cap nut. In the joint connection structure,
One end has a connecting portion and an outer tube portion provided from the connecting portion toward the other end side, while the outer tube portion is provided in a state protruding from the outer tube portion from the connecting portion toward the other end side. A joint body having an inner cylindrical portion that forms an annular groove into which the pipe is inserted while the outer periphery of the pipe abuts, and an external thread on the outer peripheral surface of the outer cylindrical portion; A female thread portion formed with a female screw to be screwed to the inner thread, an annular portion formed with a flat annular inner peripheral surface connected to the female screw, and an inner peripheral surface connected to the annular inner peripheral surface of the outer periphery of the pipe from the inner peripheral surface. It has a pipe insertion hole formed in a taper surface or a curved surface that tapers toward the other end that comes into contact, and when connected to the joint body, between the annular part and the pipe insertion hole and the inner cylinder part , A bag capable of forming an annular space for pipe insertion communicating with the annular groove Nuts,
The cap nut is inserted into the cap nut from the side of the female thread, straddles the taper surface or curved surface and the annular inner peripheral surface, and the upper end outer peripheral surface is in contact with the taper surface or curved surface. With caulking,
In order to support this caulking ring, a support ring that is fitted into the cap nut from the female screw portion side of the cap nut and disposed on the annular inner peripheral surface;
A ring with a claw that is fitted to the bag nut from the female thread side of the cap nut so as to be in contact with the outer periphery of the pipe inserted into the annular groove, and is disposed on the annular inner peripheral surface. And
As a pipe, a composite pipe having at least a three-layer structure in which a metal layer made of a metal material is sandwiched between synthetic resin layers made of a synthetic resin material,
In order to prevent the pipe inserted into the annular groove through the annular space, the metal layer of the pipe is compressed by the caulking claw provided in the caulking ring, and the metal outer peripheral surface of the metal layer is reduced in diameter. It is characterized (claim 1).

In this case, the inner cylinder portion has a plurality of upper and lower O-ring grooves on the outer peripheral surface facing the connecting portion and the outer cylinder portion, respectively, and the pipe is annularly formed via a ring-shaped insulating guide inserted through the inner cylinder portion. Configured to be inserted into the groove,
The ring-shaped insulation guide is formed such that the inner surface on the front end side is a tapered surface or a curved surface that spreads so as not to damage the O-ring fitted in the O-ring groove,
The joint body has a peephole that communicates with the annular groove in a portion where the annular groove is located, in order to function so as to serve as a guide for the end of the pipe insertion operation,
Further, the connecting portion and the outer cylindrical portion are coupled by a female screw provided in the connecting portion and a male screw provided in the outer cylindrical portion, and the connecting portion is formed from a small inner diameter portion and a large inner diameter portion provided on one end side and the other end side. The inner diameter large diameter portion has a female thread through a step portion formed between the inner diameter small diameter portion and the inner diameter large diameter portion,
Further, the outer cylinder portion has an annular placement surface on which the ring with the claw can be placed at the tip,
The inner cylinder part is provided separately from the connection part and the outer cylinder part, and has an outward flange located between the stepped part and the outer cylinder part, and is rotatable around the axis of the joint body. It is provided in
In addition, when the pipe and joint are connected, fluid pressure acts on the connection part of the pipe and joint, or when the pipe expands or contracts due to thermal expansion due to temperature change, or external force acts on the pipe, Together with the pipe displaced in the direction opposite to the pipe insertion direction in which the pipe is pulled out, the caulking ring is also connected to the outer periphery of the pipe via the clawed ring and the support ring. The inner cylinder portion has an annular recess at a position facing the caulking claw of the displaced caulking ring so that the metal layer is compressed by the caulking claw that allows the caulking claw to be prevented from coming off by displacing the pin to one end side. Preferred (claim 2).

  Furthermore, in this invention, the pipe is preferably a composite pipe having at least a three-layer structure in which a metal layer made of a metal material such as aluminum is sandwiched between synthetic resin layers made of a synthetic resin material such as crosslinked polyethylene. (Claim 3).

  In this invention, when the fluid pressure acts on the connection portion between the pipe and the joint, or the pipe expands and contracts due to thermal expansion due to temperature change, or when external force acts on the pipe or the like and a force is applied in the direction in which the composite pipe comes out. The caulking ring is narrowed and the composite pipe is crimped with the caulking claws, so that the compression of the caulking ring with the caulking claws extends to the metal layer of the composite pipe. Can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings. The present invention is not limited thereby.

1 to 6 show an embodiment of the present invention. FIG. 1 shows the appearance of the joint, and FIGS. 2 to 4 show the connection procedure between the composite pipe and the joint. FIG. 2 shows the joint before insertion of the composite pipe, FIG. 3 shows a state during insertion of the composite pipe, and FIG. 4 shows a state where the composite pipe and the joint are connected. FIG. 5 is a diagram showing that the caulking of the caulking ring by the claw extends to the metal layer of the composite pipe. FIG. 6 shows caulking.
1 to 6, reference numeral 1 denotes a composite pipe having a three-layer structure (hereinafter simply referred to as a pipe), and a metal material (for example, aluminum) between synthetic resin layers 2 and 3 made of a synthetic resin material such as crosslinked polyethylene. A metal layer 4 is sandwiched.

The connection structure between the pipe 1 and the joint 5 is such that the pipe 1 and the joint 5 are connected by inserting the pipe 1 into the joint 5 in a pre-assembled state without tightening the cap nut 6 as shown in FIGS. It is configured to
In the connection structure, a plurality of claws (caulking claws) 15 project inward from the inner peripheral surface through a joint body 11, a cap nut 6, and a notch a having a U-shape in front view formed at equal intervals. And a caulking ring 12 formed on the same circumference, a support ring 13, and a ring 14 with claws.

The joint body 11 is made of copper, has a connection portion 7 at one end, and has an outer cylinder portion 8 provided from the connection portion 7 toward the other end side, and from the connection portion 7 toward the other end side. It has an inner cylinder part 10 which is provided in a state protruding from the outer cylinder part 8 and forms an annular groove 9 into which the pipe 1 is inserted while the outer periphery of the pipe 1 is in contact with the outer cylinder part 8. An external thread 20 is provided on the outer peripheral surface.
The cap nut 6 has an internal thread portion 22 formed with an internal thread 21 that is threadedly engaged with the external thread 20 of the outer cylinder portion 8 sequentially from one end side, and an annular portion 24 formed with a flat annular inner peripheral surface 23 connected to the internal thread 21. In addition, the inner peripheral surface 25 connected to the annular inner peripheral surface 23 has a pipe insertion hole portion 26 formed in a tapered surface that tapers toward the other end side where the outer periphery 1a of the pipe 1 comes into contact with the inner peripheral surface 25. At the same time, an annular space S for pipe insertion communicating with the annular groove 9 is formed between the annular portion 24 and the pipe insertion hole portion 26 and the inner cylinder portion 10 when connected to the joint body 11. The caulking ring 12 is fitted into the cap nut 6 from the female screw portion 22 side of the cap nut 6 and straddles the tapered surface 25 and the annular inner peripheral surface 23, and the upper end outer peripheral surface 12 a is a lower portion of the tapered surface 25. It arrange | positions previously in the state contact | abutted to.
The support ring 13 is preliminarily disposed on the annular inner peripheral surface 23 so as to be fitted into the cap nut 6 from the female screw portion 22 side of the cap nut 6 in order to support the caulking ring 12. The support ring 13 has an inverted L-shaped longitudinal section.
The ring 14 with claws is fitted into the bag nut 6 from the side of the female threaded portion 22 of the cap nut 6 so as to be in contact with the outer periphery 1a of the pipe 1 inserted into the annular groove 9 in a state of being directly below the support ring 13. It is rarely disposed on the annular inner peripheral surface 23 in advance. A plurality of claws 14a are formed on the same circumference in a state of projecting inwardly downward from the inner circumferential surface.
The connecting structure compresses the metal layer 4 of the pipe 1 by the caulking claw 15 provided on the caulking ring 12 in order to prevent the pipe 1 inserted into the annular groove 9 through the annular space S. The metal outer peripheral surface of the metal layer 4 is configured to have a reduced diameter.

Furthermore, the inner cylinder part 10 has a plurality of upper and lower O-ring grooves 30 on the outer peripheral surface facing the connection part 7 and the outer cylinder part 8, respectively, and the pipe 1 is ring-shaped insulation inserted into the inner cylinder part 10. It is inserted into the annular groove 9 through the guide 31.
As shown in FIG. 3, the ring-shaped insulating guide 31 is formed such that the inner surface 31 a on the front end side is a tapered surface that is widened so as not to damage the O-ring 33 fitted in the O-ring groove 30. Yes.
In addition, the joint body 11 has a plurality of peep holes 35 communicating with the annular groove 9 in a portion where the annular groove 9 is located so as to function as a guideline for ending the insertion operation of the pipe 1. The connecting portion 7 and the outer cylindrical portion 8 are connected by a female screw 7 a provided in the connecting portion 7 and a male screw 8 a provided in the outer cylindrical portion 8.
The connecting portion 7 is composed of an inner diameter small diameter portion 40 and an inner diameter large diameter portion 41 provided on one end side and the other end side, and via a step portion 42 formed between the inner diameter small diameter portion 40 and the inner diameter large diameter portion 41. The inner diameter large diameter portion 41 has a female screw 7a.
The outer cylinder 8 has an annular mounting surface 44 (see FIG. 4) on which the ring 14 with the claw can be mounted at the tip.
The inner cylinder part 10 is provided separately from the connection part 7 and the outer cylinder part 8, and has an outward flange 10 a (see FIG. 2) located between the stepped part 42 and the outer cylinder part 8. The joint body 11 is provided so as to be rotatable about the axis.

Further, in a state in which the pipe 1 and the joint 5 are connected, fluid pressure acts on the connection portion between the pipe 1 and the joint 5, or the pipe 1 expands and contracts due to thermal expansion, or an external force is applied to the pipe 1. when acting on the equal, the pipe 1 to be displaced in the opposite direction (B direction) (see FIGS. 4 and 5) and the pipe 1 is pulled Rupa type insertion direction (a direction) (see FIG. 3), the pipe 1 A caulking claw 15 that allows the caulking ring 12 to be prevented from coming off by displacing the tapered surface 25 of the cap nut 1 to one end side through the ring 14 with the claw and the support ring 13 that are in contact with the outer periphery 1a of the cap nut 1. The inner cylinder part 10 has an annular recess 49 at a position facing the caulking claw 15 of the displaced caulking ring 12 so that the compression due to the above reaches the metal layer 4 as shown in FIG.

  Thus, in the state where the pipe 1 and the joint 5 are connected as shown in FIG. 4, the fluid pressure acts on the connection structure between the pipe 1 and the joint 5 during use, or the pipe 1 is heated due to a temperature change. When expansion or contraction occurs or an external force acts on the pipe 1 or the like, that is, the pipe 1 is displaced in the B direction. However, the clawed ring 14 and the support ring 13 that are in contact with the outer periphery 1a of the pipe 1 are also displaced together with the pipe 1, and finally the caulking ring 12 is also displaced to the one end side of the tapered surface 25 of the cap nut 1. As a result, the caulking ring 12 is reduced in diameter. Therefore, the caulking claw 15 enters the metal layer 4 and compresses the metal outer peripheral surface to reduce the diameter of the metal outer peripheral surface. Therefore, a stable retaining effect can be obtained when the composite pipe 1 is connected. That is, in the one-touch connection type pipe-joint connection structure in which the pipe is inserted into the joint that has been assembled in advance without tightening the cap nut, the reliability of retaining can be improved. And, in the conventional method that only bites the nails, there is a risk that the pipe will come out when the bited portion in the pipe is scraped, but in this invention, the pipe is removed by caulking the aluminum layer so that it does not come off physically. It is possible to avoid situations such as exiting.

As described above, the pipe can be easily connected to the joint with one touch, and the same retaining strength as that of the caulking type can be secured, and this embodiment has the following effects.
(1) The ring-shaped insulating guide 31 can prevent corrosion of the pipe 1 and the inner cylinder portion 10 due to contact between different metals of copper and aluminum.
(2) Since the inner cylinder part 10 is provided separately from the connection part 7 and the outer cylinder part 8 and is provided so as to be rotatable around the axis of the joint body 11, the caulking claw 15 enters the metal layer 4 and the metal Even after the outer peripheral surface is compressed and the metal outer peripheral surface is reduced in diameter, the pipe 1 and the inner cylinder portion 10 can be rotated integrally. As a result, the pipe 1 and the inner cylinder part 10 are rotatable, so that the pipe 1 can be prevented from being twisted and can be easily constructed.

It is a figure which shows the external appearance of the coupling in one embodiment of this invention. It is composition explanatory drawing which shows the coupling before the pipe insertion in the connection procedure of the pipe and coupling in the said embodiment. It is composition explanatory drawing which shows the state during the insertion of the pipe in the connection procedure of the pipe and joint in the said embodiment. It is composition explanatory drawing which shows the state in which the composite pipe and joint in the connection procedure of the pipe and joint in the said embodiment are connected. It is a figure which shows that the compression by the caulking nail | claw of the caulking in the said embodiment has reached even the metal layer of a composite pipe. (A) is a top view of the caulking used in the above embodiment. (B) is a longitudinal section of the caulking ring used in the above embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Composite pipe 1a Outer periphery 4 Metal layer 5 Joint 6 Cap nut 7 Connection part 8 Outer cylinder part 9 Annular groove 10 Inner cylinder part 11 Joint main body 12 Caulking ring 12a Upper end outer peripheral surface 13 Support ring 14 Ring with nail 14a Nail 15 Caulking nail 20 male screw 21 female screw 22 female screw portion 23 annular inner peripheral surface 24 annular portion 25 inner peripheral surface (tapered surface)
26 Pipe insertion hole S Annular space for pipe insertion

Claims (3)

One end has a connecting portion and an outer tube portion provided from the connecting portion toward the other end side, while the outer tube portion is provided in a state protruding from the outer tube portion from the connecting portion toward the other end side. A joint body having an inner cylindrical portion that forms an annular groove into which the pipe is inserted while the outer periphery of the pipe abuts, and an external thread on the outer peripheral surface of the outer cylindrical portion; A female thread portion formed with a female screw to be screwed to the inner thread, an annular portion formed with a flat annular inner peripheral surface connected to the female screw, and an inner peripheral surface connected to the annular inner peripheral surface of the outer periphery of the pipe from the inner peripheral surface. It has a pipe insertion hole formed in a taper surface or a curved surface that tapers toward the other end that comes into contact, and when connected to the joint body, between the annular part and the pipe insertion hole and the inner cylinder part , A bag capable of forming an annular space for pipe insertion communicating with the annular groove Nuts,
The cap nut is inserted into the cap nut from the side of the female thread, straddles the taper surface or curved surface and the annular inner peripheral surface, and the upper end outer peripheral surface is in contact with the taper surface or curved surface. With caulking,
In order to support this caulking ring, a support ring that is fitted into the cap nut from the female screw portion side of the cap nut and disposed on the annular inner peripheral surface;
A ring with a claw that is fitted to the bag nut from the female thread side of the cap nut so as to be in contact with the outer periphery of the pipe inserted into the annular groove, and is disposed on the annular inner peripheral surface. And
As a pipe, a composite pipe having at least a three-layer structure in which a metal layer made of a metal material is sandwiched between synthetic resin layers made of a synthetic resin material,
In order to prevent the pipe inserted into the annular groove through the annular space, the metal layer of the pipe is compressed by the caulking claw provided in the caulking ring, and the metal outer peripheral surface of the metal layer is reduced in diameter. Characteristic pipe and joint connection structure. The inner cylinder part has a plurality of upper and lower O-ring grooves on the outer peripheral surfaces facing the connection part and the outer cylinder part, respectively, and the pipe is inserted into the annular groove via a ring-shaped insulating guide inserted through the inner cylinder part. Configured to
The ring-shaped insulation guide is formed such that the inner surface on the front end side is a tapered surface or a curved surface that spreads so as not to damage the O-ring fitted in the O-ring groove,
The joint body has a peephole that communicates with the annular groove in a portion where the annular groove is located, in order to function so as to serve as a guide for the end of the pipe insertion operation,
Further, the connecting portion and the outer cylindrical portion are coupled by a female screw provided in the connecting portion and a male screw provided in the outer cylindrical portion, and the connecting portion is formed from a small inner diameter portion and a large inner diameter portion provided on one end side and the other end side. The inner diameter large diameter portion has a female thread through a step portion formed between the inner diameter small diameter portion and the inner diameter large diameter portion,
Further, the outer cylinder portion has an annular placement surface on which the ring with the claw can be placed at the tip,
The inner cylinder part is provided separately from the connection part and the outer cylinder part, and has an outward flange located between the stepped part and the outer cylinder part, and is rotatable around the axis of the joint body. It is provided in
In addition, when the pipe and joint are connected, fluid pressure acts on the connection part of the pipe and joint, or when the pipe expands or contracts due to thermal expansion due to temperature change, or external force acts on the pipe, Together with the pipe displaced in the direction opposite to the pipe insertion direction in which the pipe is pulled out, the caulking ring is also connected to the outer periphery of the pipe via the clawed ring and the support ring. The inner cylindrical portion has an annular recess at a position facing the caulking claw of the displaced caulking ring so that the metal layer is compressed by the caulking claw that allows the caulking claw to allow the stopper to be displaced by displacing the pin to one end side. The connection structure of the pipe and joint as described in 1.   The pipe according to claim 1 or 2, wherein the pipe is a composite pipe having at least a three-layer structure in which a metal layer made of a metal material such as aluminum is sandwiched between synthetic resin layers made of a synthetic resin material such as crosslinked polyethylene. And joint connection structure.

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