JP2012077804A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a one-touch type pipe joint, in which a connected pipe is not damaged or a flaw that may become a cause of subsequent water leakage accident is not made because of biting of a locking claw even when large force in a loosening direction is added to the connected pipe.SOLUTION: The pipe joint includes biting restriction parts 53 disposed in both sides of a locking claw 52 of a retaining ring 5a. When a locking claw 52 bites into a specified position in front of position reaching an intermediate layer 93 of an outer layer 91 of a composite pipe 9, the biting restriction part 53 comes into contact with an outer circumference face of the composite pipe 9 to prevent the locking claw 52 from further biting.

Description

  The present invention relates to, for example, a one-touch type pipe joint that can connect a connecting pipe simply by being inserted.

  A nozzle part (also referred to as a nipple part) that enters the connection pipe at the time of connection is provided, and a ring-shaped sealing material having an outer diameter larger than that of the nozzle part is fitted into an annular groove formed on the outer periphery of the nozzle part. When the ring-shaped sealing material is in close contact with the inner peripheral surface of the connecting pipe in a watertight manner, and when a force in the pulling direction is applied to the connecting pipe, the locking claws provided radially from the outer peripheral direction of the connecting pipe bite into the pipe wall and connect There is a one-touch type pipe joint provided with a metal retaining ring designed to prevent the pipe from coming off (Patent Document 1).

JP 2007-177978 A

  However, in the case of the pipe joint described in Patent Document 1, if a large force is applied to the connecting pipe in the pulling direction, the locking claws may bite in, break through the pipe wall of the connecting pipe, and damage the connecting pipe.

  In view of the above circumstances, the present invention is a one-touch type that does not cause damage to the connection pipe due to the biting of the locking claws or damage to the subsequent water leakage even if a large force is applied to the connection pipe. It aims to provide a pipe joint.

  In order to achieve the above object, a pipe joint according to the present invention forms a connection pipe insertion space between a joint body having a nozzle part that is inserted into the connection pipe when connected, and the nozzle part. An outer cylindrical portion and a ring-shaped sealing material fitted in an annular groove provided in the nozzle portion, and when a force in the pulling direction is applied to the connected connecting pipe, an outer peripheral side is formed on the pipe wall of the connecting pipe A pipe provided at the entrance of the insertion space is provided with a retaining ring provided with a plurality of locking claws that dig into the pipe and prevent the connection pipe from coming off radially and inclined toward the rear end side of the nozzle portion. In the joint, when the locking claw bites into the pipe wall up to a specified amount, the retaining ring comes into contact with the outer peripheral surface of the connecting pipe, and a biting restricting portion that prevents further biting of the locking claw is locked. It is provided adjacent to the nail .

  In the present invention, the material of the retaining ring is not particularly limited, and examples thereof include copper alloys such as steel (spring steel), stainless steel, and gun metal.

In the present invention, the pipe to be connected is not particularly limited, and examples thereof include a cross-linked polyethylene pipe, a polybutene pipe, a composite pipe having an inner layer and an outer layer made of a thermoplastic resin, and a metal intermediate layer.
The composite pipe is not particularly limited, but, for example, a commercially available product such as Slonsui Chemical Co., Ltd. manufactured by Sekisui Chemical Co., Ltd., in which the outer layer is made of high-density polyethylene, the inner layer is made of heat-resistant polyethylene, and the intermediate layer is made of aluminum. Things can be used.

  In the present invention, the prescribed amount can prevent the connection pipe from coming off even if a force in the pulling direction is applied to the connection pipe, and the connection pipe is damaged by the biting of the locking claws or causes damage to the subsequent water leakage accident. The amount of engagement of the locking claw that does not occur is determined as appropriate according to the pipe to be connected.

When the connecting pipe is a composite pipe, when the retaining ring is formed of a metal different from the intermediate layer of the composite pipe, it is preferable to limit the biting length of the locking claw to be less than the thickness of the outer layer.
That is, the reason for this is that when the biting length of the locking claw exceeds the thickness of the outer layer, the locking claw and the intermediate layer are brought into contact with each other due to the biting, and the retaining ring or the intermediate layer is formed by contact corrosion between different metals. This is because it may corrode and cause water leakage.

In the pipe joint according to the present invention, when the retaining ring is applied with a force in the disconnecting direction to the connecting pipe, the locking claw and the biting restricting portion rise so as to be orthogonal to the pipe axis of the connecting pipe, and the biting restricting The portion is configured to press and deform the tube wall of the connecting tube in the tube central axis direction, and the tube portion of the connecting tube that has been pressed and deformed enters the position corresponding to the rising biting restriction portion. It is preferable to provide an annular groove.
That is, as described above, not only the catching claw bites, but also the tube wall that presses and deforms and bites into the annular groove can receive the force in the pulling direction, and can withstand a larger pulling direction force. Can do.

As described above, the pipe joint according to the present invention includes a joint body having a nozzle part that is inserted into the connection pipe when connected, and an outer cylinder part that forms an insertion space for the connection pipe between the nozzle part. When,
A ring-shaped sealing material fitted in an annular groove provided in the nozzle portion, and when a force in the disconnecting direction is applied to the connected connecting pipe, the connecting pipe is bitten into the pipe wall of the connecting pipe from the outer peripheral side. In the pipe joint provided at the inlet of the insertion space, a retaining ring provided with a plurality of locking claws for preventing the slipping of the nozzle part radially and inclined toward the rear end side of the nozzle portion is provided in the insertion joint. When the locking claw bites into the tube wall to the specified amount, the locking ring comes into contact with the outer peripheral surface of the connecting pipe, and a biting restricting portion that prevents further locking claw biting is adjacent to the locking claw. Since it is provided, even if a large force in the pulling direction is applied to the connecting pipe, the connecting pipe is not damaged by the biting of the locking claws, or damage to the subsequent water leakage accident is not caused.

It is sectional drawing showing one embodiment of the pipe joint concerning this invention. It is sectional drawing of the state which connected the composite pipe as a connection pipe to the pipe joint of FIG. It is an expanded sectional view of the ring-shaped sealing material part of the pipe joint of FIG. It is sectional drawing of the guide member of the pipe joint of FIG. It is a perspective view of the retaining ring of FIG. The punching piece used for manufacture of the retaining ring in FIG. 5 is shown, in which FIG. 5A is a plan view thereof, and FIG. 5B is an end view taken along the line XX of FIG. 5 shows the intermediate stage of the manufacturing process of the retaining ring using the punched piece of FIG. 5, wherein FIG. 5A is a plan view thereof, and FIG. 5B is an end view of the YY line cross section of FIG. It is. FIG. 6 is an end view of a cross section of the retaining ring of FIG. 5. It is sectional drawing showing the state in the middle of inserting a composite pipe in the pipe joint of FIG. It is an expanded sectional view of the nozzle part rear end part in the connection state of the composite pipe | tube of FIG. It is an expanded sectional view of the latching claw part explaining the effect | action of the retaining ring latching claw when the force of a drawing direction is added to the composite pipe connected to the pipe joint of FIG. It is sectional drawing explaining the effect | action of a retaining ring when the force of the big pulling direction is added to the composite pipe connected to the pipe joint of FIG. It is a perspective view showing the modification of the retaining ring used for the pipe joint concerning this invention.

Hereinafter, the present invention will be described in detail with reference to the drawings showing embodiments thereof.
FIG. 1 shows one embodiment of a pipe joint according to the present invention.

As shown in FIG. 1, the pipe joint A includes a joint body 1, an outer cylinder member 2 and a cap member 3 constituting an outer cylinder portion, a ring-shaped sealing material 4, a retaining ring 5 a, and a guide member 6. As shown in FIG. 2, the composite pipe 9 is connected.
The composite tube 9 includes an outer layer 91 made of high-density polyethylene, an inner layer 92 made of heat-resistant polyethylene, and an intermediate layer 93 made of aluminum.

  The joint body 1 is formed of a metal material such as gun metal or stainless steel, and includes a hexagonal nut-like flange portion 1a that engages with an engaging portion of a tightening tool (not shown) such as a spanner at the center. A male screw cylinder 1b is provided on one side of the part 1a, and an outer cylinder receiving part 1c and a nozzle part 1d are provided on the other side.

The nozzle portion 1d includes an insertion guide portion 10, a first annular groove 11, a second annular groove 12, a third annular groove 13, and a detent ridge 14 on the peripheral surface from the distal end side, and a maximum diameter portion is connected. The diameter is slightly smaller than the inner diameter of the composite tube 9.
Even if the outer diameter of the insertion guide portion 10 toward the tip of the nozzle portion 1d becomes flat when the connecting pipe described later is cut, within the normally expected flatness range (70 to 75%), The tapered surface gradually decreases in diameter at an angle of about 30 degrees so that the diameter is smaller than the minimum diameter portion of the flat end of the connecting pipe.

The 1st annular groove 11 is provided in the position which faces the retaining ring 5a mentioned later.
As shown in FIG. 3, the second annular groove 12 is provided so that a reduced-diameter cylindrical portion 61b of a guide member 6 to be described later fits in, and its bottom surface gradually contracts toward the tip end side of the nozzle portion 1d. The diameter is a tapered surface, and the rear end side of the nozzle portion 1 d is connected to the third annular groove 13.
The third annular groove 13 is formed so that the positioning protrusion 13a of the ring-shaped sealing material 4 is annular with respect to the central axis of the nozzle portion 1d slightly closer to the insertion end of the nozzle portion 1d than the central portion in the central axis direction of the nozzle portion 1d on the bottom surface In preparation.

The detent protrusion 14 is provided along the side wall of the third annular groove 13 on the nozzle portion 1d side, and the height thereof is engaged with the rear end of the guide member 6 so that the insertion end of the nozzle portion 1d is inserted. If the movement to the side can be suppressed, it is preferably low, and is about 0.05 mm.
The outer cylinder receiving portion 1c is provided between the nozzle portion 1d and the flange portion 1a, has a slightly larger diameter than the nozzle portion 1d, and an engagement protrusion 21 of the outer cylinder member 2 described later on the peripheral surface thereof. An engagement groove 15 is formed to engage with.

The ring-shaped sealing material 4 is formed of a synthetic rubber such as EPDM (ethylene-propylene-diene copolymer), and as shown in FIG. 3, a main body portion 41, a first seal portion 42, and a second seal. Part 43.
The main body 41 is slightly narrower than the length of the third annular groove 13 in the central axis direction of the nozzle, and the thickness thereof is substantially the same as or slightly thinner than the length from the bottom of the third annular groove 13 to the outer edge of the nozzle 1d. When the engaging groove 41a in which the positioning protrusion 13a is fitted on the inner peripheral surface of the cylinder is annularly provided on the inner peripheral surface of the cylinder and no compression force is applied from the outer periphery, the third annular groove 13 is formed. In the fitted state, a gap S serving as a clearance space during compression is formed between the third annular groove 13 and the wall on the rear end side of the nozzle portion and between the wall on the second annular groove 12 side. It is like that.

The first seal portion 42 is provided on the front end side of the nozzle portion with respect to the engagement groove 41a, and the cross section gradually increases in diameter from the front end side to the rear end side of the nozzle portion 1d as indicated by a broken line in FIG. It has a substantially triangular shape, and its maximum diameter is larger than the inner diameter of the composite tube.
The second seal portion 43 is provided on the rear end side of the nozzle portion with respect to the engagement groove 41a. As shown in FIG. 3, the second seal portion 43 has a substantially semi-cylindrical cross section, and its maximum diameter is larger than the inner diameter of the composite pipe. ing.

The guide member 6 is formed by pressing, drawing and bending a pipe made of thin stainless steel or copper alloy having a wall thickness of about 0.1 mm, and as shown in FIG. A tapered portion 62 as a non-contact state holding structure and a flange portion 63 are provided.
The guide tube portion 61 includes a tube portion main body 61a and a reduced diameter tube portion 61b.

The cylinder main body 61 a has a cylindrical shape whose outer diameter is substantially the same as or slightly smaller than the inner diameter of the composite pipe 9.
The reduced diameter cylindrical portion 61b is connected to the distal end side of the nozzle portion 1d of the cylindrical portion main body 61a, gradually decreases in diameter toward the distal end side of the nozzle portion 1d, and the outer diameter on the distal end side of the nozzle portion 1d is combined. The diameter is about 5% smaller than the inner diameter of the tube 9.

  The taper portion 62 is provided so as to gradually increase in diameter from the rear end side of the nozzle portion 1d of the cylindrical portion main body 61a toward the rear end direction of the nozzle portion 1d, and the taper angle is 15 to 45 degrees. Although not particularly limited, it is preferably close to the angle of chamfering or chamfering of the pipe end face, and in this embodiment, it is 30 degrees.

  The flange 63 is formed by bending and polymerizing the end of the pipe, and the outer diameter thereof is slightly smaller than the outer diameter of the composite pipe 9.

As shown in FIGS. 1 to 3, the initial position of the guide member 6a is such that the guide tube portion 61 is externally fitted to the first seal portion 42 and the distal end side of the nozzle portion 1d of the reduced diameter tube portion 61b. The end portion is mounted so as to fit into the second annular groove 12, and the flange portion 63 is disposed in front of the second seal portion 43. Due to this arrangement, it does not move against shock and vibration.
In the state where the guide member 6 a is mounted, the ring-shaped sealing material 4 is in a state where the first seal portion 42 is compressed by the guide tube portion 61.

The outer cylinder member 2 is a cylindrical body formed of a transparent engineering plastic such as PPS (polyphenylene sulfide), PPSU (polyphenylsulfone), PC (polycarbonate), etc., and engages with the inner peripheral surface of one end portion. After the protrusion 21 is provided and the other end side is once bulged outward and becomes thick, the outer peripheral surface is notched, and two engagement grooves 22 and 22 are formed in the notch. .
In addition, the outer cylinder member 2 has an inner diameter that is substantially the same as or slightly larger than the outer diameter of the composite tube 9, and the inner peripheral surface of the outer peripheral surface is expanded in a stepped manner from the other portion. An enlarged diameter portion 23 is provided.
A retaining ring positioning recess 24 is provided in a ring shape on the end surface of the outer cylindrical member 2 on the distal end side of the nozzle portion 1d so as to follow the shape of a main body 51 of a retaining ring 5 described later.

The outer cylinder member 2 is fitted on the outer cylinder receiving portion 1c so that one end thereof is engaged with the engaging groove 15 of the outer cylinder receiving portion 1c. ing.
That is, the outer cylinder member 2 is detached from the joint body 1 when the engagement protrusion 21 is pushed in the direction of the joint body 1 while being elastically deformed, and the engagement protrusion 21 is engaged with the engagement groove 15. Instead, it is rotatably attached to the joint body 1.

As shown in FIG. 5, the retaining ring 5 a includes a ring-shaped main body 51, and a plurality of locking claws 52 and biting restriction portions 53 on the inner peripheral side of the main body 51 alternately.
The retaining ring 5a is first punched out of a thin stainless steel plate, and as shown in FIG. 6, a locking claw 52 and a biting restricting portion 53 on both sides of the locking claw 52 are formed inside the main body 51. After the punched piece 5 provided with the tongue piece 50 is obtained, the protruding length of the tongue piece 50 of the punched piece 5 from the biting restricting portion 53 of the locking claw 52 is the outer layer of the composite tube 9 as shown in FIG. By bending 180 ° at a position where the thickness is less than 91, and further raising the bent portion and the locking claw 52 to the main body 51 at an intersection angle of 40 to 45 °, as shown in FIG. can get.

  The retaining ring 5a is held in a state in which the main body 51 is fitted into the retaining ring positioning recess 24, and the engaging claw 52 and the biting restricting portion 53 are accommodated in the enlarged diameter portion 23 (see FIG. 11). ).

The cap member 3 includes a cap body 31 formed of a transparent engineering plastic such as PPS (polyphenylene sulfide), PPSU (polyphenylsulfone), PC (polycarbonate), and a fitting cylinder portion 32.
The cap body 31 has an inner diameter on the tube insertion end side that is substantially the same as or slightly larger than the outer diameter of the composite tube 9, and extends from the intermediate portion to the tip (the end opposite to the fitting tube portion 32). It has.
The guide portion 31a has a tapered surface whose inner diameter gradually increases toward the tip of the cap body 31 at an angle of about 30 degrees, and the inner diameter of the tip is flat when the composite tube 9 described later is cut. Even in this case, the diameter is larger than the maximum outer diameter at the end of the flattened composite pipe 9 in the normally expected flatness range (70 to 75%).

The fitting cylinder portion 32 is provided so as to extend to one side in the thickness direction of the cap body 31, and two engagement protrusions 32a and 32a are provided on the inner peripheral surface.
The cap member 3 is fitted onto the outer cylinder member 2 so that the engagement protrusions 32a and 32a are fitted into the engagement grooves 22 and 22 of the outer cylinder member 2, respectively. The detachment of the retaining ring 5a is prevented.

This pipe joint A is as described above, and the composite pipe 9 is connected by one-touch insertion as follows.
First, after the male threaded cylinder portion 1b of the joint body 1 is screwed into a piping material (for example, a header) not shown and connected to another piping material, the composite pipe 9 is opened from the opening of the cap member 3 to the joint body. When inserted into the first side, the tip of the composite tube 9 is elastically deformed in the direction in which the locking claw 52 and the biting restriction portion 53 of the retaining ring 5 are first inserted, so that the locking claw 52 as shown in FIG. In addition, the biting restriction portion 53 extends along the outer wall of the composite pipe 9.

When the composite tube 9 is further pushed in, as shown in FIG. 9, the outer diameter at the tip of the reduced diameter cylindrical portion 61b is smaller than the inner diameter of the composite tube 9, so the taper of the reduced diameter cylindrical portion 61b. While being guided by the surface, the tube body 61a smoothly enters the tip of the composite tube 9, the entire guide tube portion 61 enters the composite tube 9, and is received by the tapered portion 62 at the tip of the inner layer 92 of the composite tube 9. .
When the composite pipe 9 is further pushed in, the taper portion 62 is pushed by the inner layer 92 of the composite pipe 9, and the guide member 6 is inserted into the nozzle portion rear end side together with the composite pipe 9, as shown in FIGS. As shown in FIG. 10, the collar portion 63 contacts the end surface of the outer tube receiving portion 1 c, and the guide tube portion 61 enters the nozzle portion rear end side from the detent protrusion 14. Further, the first seal portion 42 and the second seal portion 43 of the ring-shaped sealing material 4 are in close contact with the inner peripheral surface of the composite pipe 9 in a watertight manner.

This pipe joint A is as described above, and has the following excellent effects.
(1) Since the retaining ring 5a is provided, the composite tube 9 can be reliably prevented from coming off. That is, when a force in the pulling direction is applied to the composite tube 9 and the composite tube 9 tries to move in the pulling direction, first, the locking claw 52 bites into the outer layer 91 of the composite tube 9 as shown in FIG. When the force is not large, the movement in the pulling direction is suppressed only by this biting. In addition, since the retaining ring 5a includes the biting restriction portions 53 on both sides of the locking claw 52, when the locking claw 52 bites into a predetermined position, the biting restriction portion 53 comes into contact with the outer peripheral surface of the composite pipe 9. Further, biting into the outer layer 91 of the locking claw 52 is prevented. Therefore, the composite pipe 9 can be prevented from being damaged due to excessive engagement of the locking claws 52.
(2) Since the biting length of the locking claw 52 is regulated to be less than the thickness of the outer layer 91 of the composite pipe 9, the locking claw 52 does not break through the outer layer 91 and reach the intermediate layer 93. That is, contact corrosion between different metals due to direct contact between the intermediate layer 93 and the retaining ring 5a can be prevented.
(3) When the applied force is large, as shown in FIG. 12, the locking claw 52 that bites into the outer layer 91 becomes parallel to the main body 51 as the composite tube 9 moves in the removal direction. Although it gets up, the pipe wall of the composite pipe 9 is reduced in diameter toward the nozzle part 1d by the biting restriction part 53 and enters the first annular groove 11 of the nozzle part 1d. Directional movement is restricted and no further slipping is prevented.
(4) Since the guide member 6 a is provided, the pipe end of the composite pipe 9 does not hit the ring-shaped sealing material 4. Therefore, even if the composite pipe 9 is inserted into the pipe joint A in a state where the tip is obliquely cut or the finish of the pipe end face is insufficient, the ring-shaped sealing material 4 is not damaged or detached.
(5) A tapered portion 62 is provided as a non-contact state holding means. As shown in FIG. 10, the end surface of the inner layer 92 of the composite pipe 9 is received by the tapered portion 62, and the intermediate layer 93 contacts the guide member 6. There is nothing to do. Therefore, deterioration of the intermediate layer 93 due to contact corrosion between different metals is prevented.
(6) Since the guide member 6 includes the reduced diameter cylindrical portion 61b, the guide cylindrical portion 61 smoothly enters the tube end of the composite tube 9.
(7) Since the nozzle portion 1d is provided with the detent protrusion 14, the force in the removal direction is applied to the composite tube 9 as described above, the composite tube 9 moves in the removal direction, and the guide member 6a is displaced. Even if trying to do so, the tip of the reduced diameter cylindrical portion 61 b of the guide member 6 a is locked to the detent protrusion 14. Therefore, the guide member 6a is not further displaced in the removal direction, and the ring-shaped sealing material 4 is not damaged or detached by the tip of the reduced diameter cylindrical portion 61b.
(8) The insertion guide portion 10 has a tapered surface whose outer diameter gradually decreases toward the tip of the nozzle portion 1d at an angle of about 30 degrees, and the outer diameter of the tip is flat with the cut. The guide tube 31a has a tapered surface whose inner diameter gradually increases toward the tip of the cap body 31 at an angle of about 30 degrees. In addition, since the inner diameter of the tip is larger than the maximum outer diameter of the tube end of the flattened composite tube 9 that has been cut, the composite tube 9 is flattened at the time of cutting, and in this state the composite tube Even when 9 is connected, the insertion guide portion 10 smoothly enters the distal end portion of the composite tube 9, and the composite tube 9 enters the cap body 31 from the distal end of the guide 31a. The flattened composite tube 9 is corrected to a cylindrical body by the insertion guide portion 10 and the guide portion 31a, and is smoothly fitted on the guide tube portion 61 of the guide member 6a.
(9) Since the ring-shaped sealing material 4 is pressed by the guide cylinder portion 61 of the guide member 6a, the resistance when passing through the ring-shaped sealing material 4 of the composite tube 9 is reduced, and the insertion force of the composite tube is reduced. Can be reduced. Therefore, the workability is improved.

FIG. 13 shows a modification of the retaining ring of the pipe joint according to the present invention.
As shown in FIG. 13, the retaining ring 5b is the same as the retaining ring 5a except that the retaining ring 5b is provided with a biting restricting portion 54 that is bent in a direction perpendicular to the locking claw 52. ing.

The present invention is not limited to the above embodiment. For example, in the above-described embodiment, there is one ring-shaped sealing material. However, a plurality of annular grooves for sealing material are provided in parallel to the axial direction, and a ring-shaped sealing material is fitted to each. I do not care.
In the above embodiment, the guide member is provided, but the guide member may not be provided.

A Pipe joint 1 Joint body 1d Nozzle part 11 First annular groove 2 Outer cylinder member (outer cylinder part)
3 Cap member (outer cylinder)
4 Ring-shaped sealing material 5a, 5b Retaining ring 51 Main body 52 Locking claws 53, 54 Biting restriction part 9 Composite pipe (connection pipe)
91 Outer layer 92 Inner layer 93 Intermediate layer

Claims (3)

A joint body having a nozzle portion that is inserted into the connection pipe when connected;
An outer cylinder part that forms an insertion space for the connecting pipe between the nozzle part, and
A ring-shaped sealing material fitted in an annular groove provided in the nozzle part,
When a force in the disconnecting direction is applied to the connected connecting pipe, a plurality of locking claws that bite into the pipe wall of the connecting pipe from the outer peripheral side to prevent the connecting pipe from coming out radially and on the rear end side of the nozzle portion In the pipe joint provided at the entrance of the insertion space, the retaining ring provided inclined toward the
The retaining ring comes into contact with the outer peripheral surface of the connecting pipe when the locking claw bites into the pipe wall to a specified amount, and a biting restricting portion that prevents further biting of the locking claw is adjacent to the locking claw. A pipe joint characterized in that it is provided.   The pipe joint according to claim 1, wherein the connecting pipe is a composite pipe including inner and outer layers made of thermoplastic resin and a metal intermediate layer, and the biting length of the locking claw is regulated to be less than the thickness of the outer layer. .   When a force in the disconnecting direction is applied to the connection pipe, the retaining ring rises so that the locking claw and the biting restriction part are orthogonal to the pipe axis of the connection pipe, and the biting restriction part is centered on the pipe wall of the connection pipe. 2. The structure according to claim 1, wherein the nozzle portion is provided with an annular groove into which the tube wall portion of the connecting tube that has undergone pressure deformation enters at a position corresponding to the rising biting restriction portion. The pipe joint according to claim 2.

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