JP2024042095A - Pipe joint - Google Patents

Abstract

To provide a pipe joint for preventing a first seal ring from easily protruding out of a seal part when a pipe is inserted therein.SOLUTION: A pipe joint 1 has a seal part 8 formed on the inner peripheral face of a resin joint body 4 into which a pipe 2 is inserted, where a first seal ring 9 and a second seal ring 11 are arranged in sequence from the opposite side to the insertion side of the pipe 2 in the axial direction of the seal part 8. In the seal part 8, a spacer ring 10 is arranged between the first seal ring 9 and the second seal ring 11. The spacer ring 10 is shaped annular and sectionally trapezoidal.SELECTED DRAWING: Figure 2

Description

The present invention relates to a pipe joint.

Figure 5 shows the pipe joint 101 described in Patent Document 1. In the pipe joint 101, a first seal ring 109 and a second seal ring 111 are used to ensure watertightness between the pipe 102 and the pipe. The first seal ring 109 and the second seal ring 111 are housed in a seal section 108 provided in the joint body 104. In the seal section 108, a spacer ring 110 is disposed between the first seal ring 109 and the second seal ring 111 to prevent them from directly contacting each other.

The joint body 104 is made of synthetic resin, and due to mold limitations, it is necessary to separately form a seal portion that accommodates the first seal ring 109 and the second seal ring 111 (in particular, the first seal ring 109 is Since it is difficult to form a groove-shaped seal portion on the inner side to accommodate the spacer, the above-described structure using the spacer ring 110 is adopted.

JP2018-168980

However, as shown in FIG. 6, when the pipe 102 is inserted obliquely into the pipe joint 101, the spacer ring 110 receives the insertion force of the pipe 102 unevenly in a part of the circumferential direction. It is tilted relative to the first seal ring 109. If the inclination of the spacer ring 110 with respect to the first seal ring 109 becomes excessive, a portion of the first seal ring 109 in the circumferential direction is excessively pushed toward the back and radially inward (pressing force F), and as a result, the portion is There was a problem that it protruded from the seal portion 108.

An object of the present invention is to provide a pipe joint in which the first seal ring does not easily protrude from the seal portion when piping is inserted.

In order to achieve the above object, the invention of claim 1 provides that a seal portion formed on the inner circumferential surface of a resin joint main body into which a pipe is inserted has a seal portion that is connected to the insertion side of the pipe in the axial direction of the seal portion. A first seal ring and a second seal ring are arranged in order from the opposite side, and a spacer ring is provided between the first seal ring and the second seal ring in the seal portion. The spacer ring has a trapezoidal cross section, and the short side and long side, which are parallel opposite sides of the trapezoidal cross section, have one side in the radial direction. One is a pipe joint located on the inside and the other is located on the outside in the radial direction.

The present invention provides a pipe fitting in which the first seal ring is less likely to protrude from the seal portion when the pipe is inserted.

FIG. 2 is a vertical cross-sectional view showing the entire pipe joint. An enlarged view of the main part of FIG. 1. FIG. 3 is an exaggerated diagram showing a state in which piping is inserted diagonally. FIG. 7 is an enlarged view of main parts showing another example. FIG. 1 is a vertical cross-sectional view showing the entire conventional pipe joint. FIG. 3 is an exaggerated diagram showing a state in which piping is inserted diagonally.

Hereinafter, one embodiment of a pipe joint will be described.
A pipe joint 1 shown in FIG. 1 is used to connect pipes 2 made of synthetic resin through which fluid flows, and includes a joint body 4 made of synthetic resin and formed into a cylindrical shape. The piping 2 on the upstream side (the right side in FIG. 1) is inserted into the joint body 4 from one end (the right end in FIG. 1) of the joint body 4 in the axial direction. The downstream (left side in FIG. 1) piping 2 is inserted into the joint body 4 from the other end (left end in FIG. 2) of the joint body 4 in the axial direction.

In addition, since the upstream and downstream sides of the pipe fitting 1 have the same structure, only the upstream structure will be described below, and the downstream structure will be given the same reference numerals as the upstream side and will not be described.

On the inner circumferential surface of the joint body 4, an annular projection 5 is formed at the center of the joint body 4 in the axial direction. On the inner circumferential surface of the joint body 4 , a housing portion 6 for housing the end of the pipe 2 is provided in a portion near the end of the joint body 4 adjacent to the annular projection 5 . A cylindrical in-core 7 is inserted into the end of the pipe 2. The in-core 7 is prevented from sinking into the piping 2 by a flange 7a formed at the end of the in-core 7. The end of the pipe 2 into which the in-core 7 has been inserted is inserted from the end of the joint body 4 and is accommodated in the accommodating portion 6.

On the inner circumferential surface of the joint body 4 , a seal portion 8 having a larger diameter than the housing portion 6 is provided in a portion between the housing portion 6 and the corresponding end of the joint body 4 . In the seal portion 8, a first seal ring 9, a spacer ring 10, a second seal ring 11, and a retaining ring 12 are arranged in the same order from the housing portion 6 side toward the end side of the joint body 4. Since the first seal ring 9 and the second seal ring 11 are the same (all the same material, shape, dimensions, etc.), there is no trouble in identifying each other when assembling the pipe joint 1.

When the end of the piping 2 is inserted into the accommodating portion 6 of the joint body 4, the piping 2 passes through the first seal ring 9, the spacer ring 10, the second seal ring 11, and the retaining ring 12. At this time, the first seal ring 9 and the second seal ring 11 come into contact with the outer circumferential surface of the pipe 2, and due to this state, the fluid flowing through the joint body 4 flows between the outer circumferential surface of the pipe 2 and the inner circumferential surface of the joint body 4. This can prevent leakage from between the pipe joint 1 and the outside of the pipe joint 1.

The pipe joint 1 includes a holding member 13 for holding the pipe 2 on the joint body 4 and a cap 14 for attaching the holding member 13 to the joint body 4. The holding member 13 is provided with an annular lock ring 17 located between the fitting ring 15 and the split ring 16. The retaining member 13 is located adjacent to the retaining ring 12 arranged on the seal portion 8 of the joint body 4 .

The cap 14 is formed into a cylindrical shape. When the end (insertion end) of the joint body 4 is inserted into the open end (end on the joint body 4 side) of the cap 14, the holding member 13 is connected to the joint body 4 (retaining ring 12). It's sandwiched between.

The cap 14 is attached to the joint body 4 by snap-engaging its open end to the insertion end of the joint body 4 at a portion where the cap 14 overlaps the insertion end in the radial direction. By attaching the cap 14 to the joint body 4, the holding member 13 sandwiched between the joint body 4 and the cap 14 is attached to the joint body 4.

With the holding member 13 attached to the joint body 4 by the cap 14, when the end of the pipe 2 passes through the holding member 13 and the cap 14 and is inserted into the accommodating part 6 from the insertion end of the joint body 4, the holding member 13 is attached to the joint body 4 by the cap 14. The lock ring 17 of the member 13 presses the outer peripheral surface of the pipe 2, thereby preventing the pipe 2 from coming off from the joint body 4.

Next, the spacer ring 10 will be explained in detail.
As shown in FIG. 2, the spacer ring 10 has an annular shape and a trapezoidal cross section. The spacer ring 10 is a machined product made from a bar made of a metal material such as a copper alloy. Therefore, the spacer ring 10 can have higher roundness and shape retention than, for example, those made of synthetic resin.

The outer diameter of the spacer ring 10 is set to be slightly smaller than the inner diameter of the seal portion 8. Therefore, the spacer ring 10 is movable in the seal portion 8, in other words, it is easy to place the spacer ring 10 in the seal portion 8 when assembling the pipe joint 1.

The spacer ring 10 is subjected to barrel processing after the cutting process described above. Examples of the barrel treatment include barrel polishing and barrel plating (gara plating). The spacer ring 10 subjected to barrel processing has corners chamfered appropriately. Therefore, when inserting the pipe 2, etc., the contact of the spacer ring 10 against the inner circumferential surface of the seal portion 8 and the outer circumferential surface of the pipe 2 is reduced, and it is possible to prevent scratches on the circumferential surface, and prevent damage caused by the scratches. A decrease in watertightness between the first seal ring 9 and/or the second seal ring 11 can be prevented. In other words, even if the spacer ring 10 is hard and made of metal, it can slide smoothly onto the soft piping 2 and the joint body 4 (seal portion 8) made of synthetic resin.

Now, the trapezoidal cross section of the spacer ring 10 is specifically set so that the short side is on the outside in the radial direction, and the long side parallel to the short side (the opposite side to the short side) is on the inside in the radial direction. There is. Therefore, in the spacer ring 10, the first end surface 10a located on the side facing the first seal ring 9 is a conical surface that is inclined so as to be further away from the first seal ring 9 side as it goes radially outward. It has become. Note that the angle of the inclination is referred to as "inclination angle X".

FIG. 3 shows an exaggerated state in which the spacer ring 10 is tilted with respect to the first seal ring 9. As shown in FIG. The inclination of the spacer ring 10 is caused by the spacer ring 10 receiving the insertion force of the pipe 2 unevenly in a portion of the circumferential direction due to the pipe 2 being inserted diagonally into the pipe joint 1. If the inclination of the spacer ring 10 with respect to the first seal ring 9 becomes excessively large, a portion of the first seal ring 9 in the circumferential direction will excessively move toward the back through the corresponding portion of the first end surface 10a of the spacer ring 10. It is pressed (pressing force F).

However, as described above, the first end surface 10a of the spacer ring 10 is inclined with respect to the first seal ring 9 in advance. Therefore, even in a state where the inclination of the spacer ring 10 with respect to the first seal ring 9 is excessive, the first end surface 10a is inclined so as to be spaced apart from the first seal ring 9 side as it goes radially outward. ” state can be maintained.

Therefore, the portion of the first seal ring 9 in the circumferential direction that is pushed toward the inner side through the first tip surface 10a has a pressing force F that also goes toward the outside in the radial direction, in other words, remains in the seal portion 8. Force also acts in the direction you want it to move. Therefore, even if the pipe 2 is inserted diagonally, the first seal ring 9 can be prevented from protruding from the seal portion 8.

2, in order to achieve this effect, it is preferable that the inclination angle X of the first tip surface 10a of the spacer ring 10 is not close to 0 degrees. If the inclination angle X of the first tip surface 10a is close to 0 degrees, when the inclination of the spacer ring 10 with respect to the first seal ring 9 becomes excessive, the state of the first tip surface 10a is easily changed from the "inclination so that it moves away from the first seal ring 9 as it moves radially outward" to "inclination so that it moves closer to the first seal ring 9 as it moves radially outward", and a force acting radially inward is applied to the first seal ring 9, as in the conventional technology (see FIG. 6).

On the other hand, if the inclination angle X of the first end surface 10a is close to 90 degrees, the spacer ring 10 becomes sharp toward the first seal ring 9, making it easy to damage the first seal ring 9.

Considering the above and the material (for example, made of rubber such as EPDM), shape, and dimensions of the first seal ring 9, the inclination angle X of the first end surface 10a of the spacer ring 10 is preferably 20 degree to 30 degrees, more preferably 26 degrees to 28 degrees, and in this embodiment is set to 27 degrees.

In the spacer ring 10, the second end surface 10b located on the side facing the second seal ring 11 is inclined so as to be spaced apart from the second seal ring 11 as it goes radially outward. Note that the angle of the inclination is referred to as "inclination angle Y".

The inclination angle Y of the second distal end surface 10b is set to be the same as the inclination angle X of the first distal end surface 10a. Therefore, the spacer ring 10 has the same shape in the front and rear directions in the axial direction and has no directionality. Therefore, when assembling the pipe fitting 1, the first end surface 10a and the second end surface 10b can be distinguished from each other. No hassle.

This also allows the long sides of the trapezoidal cross section of the spacer ring 10 to be set long. If the long sides can be set long, the play in the axial direction of the first seal ring 9, spacer ring 10, and second seal ring 11 can be reduced even before the pipe 2 is inserted. Therefore, the inclination of the first seal ring 9, spacer ring 10, and second seal ring 11 when the pipe 2 is inserted can be suppressed, and the protrusion of the first seal ring 9 from the seal portion 8 can be suppressed more effectively. .

In other words, in the conventional technique shown in FIG. Setting it to be long in the axial direction cannot be adopted because the filling rate will be excessive. Therefore, it is necessary to adopt a spacer ring 110 that is short in the axial direction, and the play in the axial direction of the first seal ring 109, spacer ring 110, and second seal ring 111 becomes large before the pipe 102 is inserted. It ends up.

If the play is large, the inclination of each of the first seal ring 109, the spacer ring 110, and the second seal ring 111 tends to become large when the pipe 102 is inserted. This encourages the first seal ring 109 to protrude from the seal portion 108 when the pipe 102 is inserted.

As shown in FIG. 2, in the spacer ring 10, C chamfers 10c and 10d are provided between the first end surface 10a and the long side of the trapezoidal cross section, and between the second end surface 10b and the long side. is applied. The C chamfers 10c and 10d are inclined so as to be spaced apart from the corresponding first seal ring 9 or second seal ring 11 as they go radially inward.

Therefore, when the pipe 2 is inserted, the contact of the spacer ring 10 against the outer circumferential surface of the pipe 2 is reduced, and damage to the outer circumferential surface can be prevented. Therefore, it is possible to prevent a decrease in watertightness between the piping 2 and the first seal ring 9 and/or the second seal ring 11 due to the scratches.

[Another example]
○ As shown in FIG. 4, in the seal portion 8, a stepped wall surface 8a located at the boundary with the housing portion 6, in other words, located on the side facing the first seal ring 9 on the opposite side from the spacer ring 10. The wall surface 8a is inclined so as to be separated from the first seal ring 9 side as it goes radially outward. In this way, a reaction force directed outward in the radial direction is applied to the first seal ring 9 even when it comes into contact with the wall surface 8a, so that when the pipe 2 is inserted, the first seal ring 9 Protrusion from the seal portion 8 can be more effectively suppressed.

○Do not incline the second end surface 10b of the spacer ring 10. In other words, the inclination angle Y of the second tip surface 10b is set to 0 degrees.

○The spacer ring 10 should be made of synthetic resin. A synthetic resin suitable for the material of the spacer ring 10 includes, for example, a mixture of polyphenylene sulfide resin and glass fiber.

The trapezoidal cross-section of the spacer ring 10 is set so that the short side is on the inside in the radial direction and the long side parallel to the short side is on the outside in the radial direction.

○ Pipe joint 1 is a so-called socket, but it should be changed to a cheese or elbow.

○In the pipe fitting 1, all the holding members 13 are of the so-called one-touch type, but some of the holding members should be changed to other than one-touch types such as screw joints or heat fusion joints.

[Additional note]
○A first seal ring and a second seal are attached to the seal part formed on the inner peripheral surface of the resin joint body into which the pipe is inserted, in order from the side opposite to the insertion side of the pipe in the axial direction of the seal part. A pipe joint in which a spacer ring is disposed between the first seal ring and the second seal ring in the seal portion, the spacer ring being disposed between the first seal ring and the second seal ring in the seal portion. The wall surface facing the pipe joint in the axial direction is inclined so as to be spaced apart from the first seal ring as it goes radially outward.

○A seal part formed on the inner peripheral surface of the resin joint body into which the pipe is inserted has a first seal ring and a second seal in order from the side opposite to the insertion side of the pipe in the axial direction of the seal part. The pipe joint has a spacer ring disposed between the first seal ring and the second seal ring in the seal portion, the spacer ring having a trapezoidal cross section, and a spacer ring disposed between the first seal ring and the second seal ring. , the short side and the long side, which are parallel opposite sides in the trapezoidal cross section, are a pipe joint in which one is located on the inside in the radial direction and the other is located on the outside in the radial direction.

(a) A seal part formed on the inner circumferential surface of the resin joint body into which the pipe is inserted has a first seal ring and a first seal ring, which are arranged in order from the side opposite to the insertion side of the pipe in the axial direction of the seal part. two seal rings are arranged, and a spacer ring is arranged between the first seal ring and the second seal ring in the seal portion so as to be tiltable with respect to the first seal ring. The pipe joint is a pipe joint in which a distal end surface of the spacer ring located on the side facing the first seal ring is inclined so as to be further away from the first seal ring as it goes radially outward. Fittings.

(b) The pipe joint according to (a), wherein the angle of the inclination of the tip surface is 20 degrees to 30 degrees.

According to the inventions (a) and (b), the front end surface of the spacer ring located on the side facing the first seal ring is inclined in advance with respect to the first seal ring. Therefore, even when the inclination of the spacer ring with respect to the first seal ring becomes excessive, the tip surface maintains the above-mentioned state of "inclination such that it becomes more distant from the first seal ring as it goes radially outward". It is possible. Therefore, a force directed outward in the radial direction, in other words, a force that tends to remain in the seal portion acts on the portion of the first seal ring in the circumferential direction that is pushed inward through the tip surface. be done. Therefore, even if the pipe is inserted diagonally, the first seal ring can be prevented from protruding from the seal portion.

DESCRIPTION OF SYMBOLS 1... Pipe joint, 2... Piping, 4... Fitting body, 8... Seal part, 9... First seal ring, 10... Spacer ring, 10a... First tip surface, 10b... Second tip surface, 11... Second seal ring.

Claims (1)

A seal portion formed on the inner circumferential surface of the resin joint body into which the pipe is inserted has a first seal ring and a second seal ring in order from the side opposite to the insertion side of the pipe in the axial direction of the seal portion. is arranged between the first seal ring and the second seal ring in the seal portion, and a pipe joint is arranged such that a spacer ring can be tilted with respect to the first seal ring. The spacer ring has a trapezoidal cross section, and in the trapezoidal cross section, the short side and the long side, which are parallel opposite sides, are located on the inside in the radial direction and the other on the outside in the radial direction.

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