JP2024072420A - Pipe with joint and manufacturing method of pipe with joint - Google Patents

Abstract

To secure sufficient seal performance between a pipe and a joint, and to connect the pipe and the joint by a simple process.SOLUTION: A portion including one end 2a of a pipe 2 in an axial direction and an annular protrusion 11 is inserted into a joint internal space 12 of a joint 3. An O-ring 4 is placed in a clearance 13 between a portion located between one end 2a of the pipe 2 and the annular protrusion 11 of an external peripheral face 2b of the pipe 2, and a wall face 12c1 which defines an end of the joint internal space 12 of the joint 3 in a radial direction. A tapering 5, to which the pipe 2 is inserted, is pressure-inserted into the joint internal space 12 from a side opposite to the annular protrusion 11 in the axial direction. An engagement protrusion 15 formed at an external peripheral face of the tapering 5 and an engagement recess 14 formed at the wall face which defines the end of the joint internal space 12 of the joint 3 in the radial direction are engaged with each other. An adhesive 17 is interposed between the external peripheral face of the tapering 5 and the wall face which defines the end of the joint internal space 12 of the joint 3 in the radial direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to a pipe with a fitting, which is formed by connecting a pipe and a fitting, and a method for manufacturing a pipe with a fitting.

In Patent Document 1, a pipe joint to be connected to a connecting pipe has a joint body into which the connecting pipe is inserted, a pressure ring that is screwed into the joint body, and a metal seal member that is incorporated inside the joint body. The joint body has female threads formed at both ends, a tapered surface that slopes downward from the end to the center, and a circumferential groove formed on the end side. The pressure ring has a hexagonal nut-shaped head, a male thread that is screwed into the female thread of the joint body, and a ring-shaped abutment portion formed on the end side. The metal seal member has a tapered surface that abuts against the tapered surface of the joint body, and is a member formed with a wedge-shaped cross section. In addition, a ridge portion is formed along the circumferential direction on the tapered surface and inner peripheral surface of the metal seal member.

In Patent Document 1, after the metal seal member is attached inside the joint body, the pressure ring is screwed into the joint body and the abutment portion formed on the tip side of the pressure ring is abutted against the end face of the metal seal member. The pressure ring is then completely tightened. As a result, the tip of the metal seal member enters the circumferential groove of the joint body and the ridge portion is crushed, so that the tapered surface of the joint body and the tapered surface of the metal seal member come into close contact with each other, and the inner surface of the metal seal member comes into close contact with the outer surface of the connecting pipe, thereby obtaining the specified sealing performance.

JP 2008-89132 A

As described above, in Patent Document 1, the pressure ring is screwed into the joint body and tightened, so that the tip of the metal seal member enters the circumferential groove of the joint body and the ridge is crushed, so that the tapered surface of the joint body and the tapered surface of the metal seal member come into close contact with each other, and the inner surface of the metal seal member and the outer surface of the connecting pipe come into close contact with each other. In this case, in order to prevent the screwed-in pressure ring from loosening, it is necessary to manage the torque when tightening the pressure ring, which makes the work complicated.

The object of the present invention is to provide a pipe with fittings that can ensure sufficient sealing between the pipe and the fittings and can connect the pipe and the fittings in a simple process, and a method for manufacturing the pipe with fittings.

The pipe with fitting of the present invention comprises a pipe, a fitting connected to the pipe, a sealing member for sealing between the pipe and the fitting, and a fixing member for fixing the pipe and the fitting, and an annular protrusion extending around the entire circumference is formed on the outer circumferential surface of the pipe, and the fitting is inserted in the axial direction at one end of the pipe and a portion including the annular protrusion, forming a fitting inner space communicating with the pipe inner space, which is the internal space of the pipe, and has a contact surface that is a part of the wall surface defining the fitting inner space and extends in the radial direction of the pipe to come into contact with the end face of the one end side in the axial direction of the annular protrusion, and the sealing member is configured in an annular shape and is connected to a portion of the outer circumferential surface of the pipe located between the one end of the pipe and the annular protrusion and a wall surface defining the radial end of the fitting inner space. The fixing member is annular, the pipe is inserted, the pipe is positioned in the joint internal space, and is pressed into the gap between the outer circumferential surface of the portion of the pipe farther from the one end than the annular protrusion in the axial direction and the wall surface defining the radial end of the joint internal space from the opposite side of the annular protrusion in the axial direction, the end surface of the fixing member on the annular protrusion side in the axial direction contacts the annular protrusion, an engaging protrusion protruding in the radial direction is formed on the outer circumferential surface of the fixing member, an engaging recess that is radially recessed and engages with the engaging protrusion of the pressed-in fixing member is formed on the wall surface defining the radial end of the joint internal space, and an adhesive is interposed between the outer circumferential surface of the fixing member and the wall surface defining the radial end of the joint internal space.

In the present invention, the fixing member is pressed in, so that the engaging protrusion of the fixing member engages with the engaging recess of the joint, and the annular protrusion of the pipe is sandwiched between the contact surface of the joint and the fixing member, thereby fixing the pipe and the joint. At this time, the pipe and the joint are fixed by pressing in the fixing member, so that, unlike when the fixing member is screwed in to fix the pipe and the joint, complicated processes such as torque adjustment are not required. Therefore, the pipe and the joint can be easily fixed. In addition, the adhesive is interposed between the outer peripheral surface of the fixing member and the wall surface that defines the radial end of the space inside the joint, so that the joint and the tapered ring can be prevented from moving relative to each other in the axial and circumferential directions, and foreign matter can be prevented from entering between the outer peripheral surface of the fixing member and the wall surface that defines the radial end of the space inside the joint.

1A is a cross-sectional view taken along the axial direction of a fitting-equipped pipe according to an embodiment of the present invention, and FIG. 1B is an exploded view of each component of FIG. 1A is a view of the pipe from the radial outside, (b) is a view of the tapered ring from the radial outside, (c) is a view of the tapered ring from the axial annular convex portion side, and (d) is an enlarged view of the area indicated by IID in FIG. 1A. FIG. 1A is a diagram illustrating the process of attaching an O-ring to a pipe, FIG. 1B is a diagram illustrating the process of inserting the pipe with the O-ring attached into a fitting, and FIG. 1C is a diagram illustrating the process of pressing in a tapered ring. (a) is a cross-sectional view along the axial direction of a fitting pipe equipped with a tapered ring having a flange portion, (b) is a view from the radial outside of the tapered ring having the flange portion, and (c) is a view of the tapered ring having the flange portion viewed from the axial annular convex portion side.

A preferred embodiment of the present invention is described below.

<Structure of pipe with fitting>
As shown in Figures 1(a) and (b), a fitting-equipped pipe 1 of this embodiment comprises a pipe 2, a fitting 3, an O-ring 4 (the sealing member of the present invention), and a tapered ring 5 (the fixing member of the present invention).

The pipe 2 is cylindrical. An annular protrusion 11 is formed on the pipe 2. The annular protrusion 11 is formed in a portion near one end 2a of the pipe 2 in the axial direction, and protrudes from the outer peripheral surface 2b of the pipe 2 in the radial direction of the pipe 2. The annular protrusion 11 extends around the entire circumference of the outer peripheral surface 2b of the pipe 2. The annular protrusion 11 can be formed, for example, by bulging or drawing. In this embodiment, the axial directions of the pipe 2, the joint 3, the O-ring 4, and the tapered ring 5 are the same, so hereinafter, these axial directions may be simply referred to as the axial direction. Also, hereinafter, the radial direction of the pipe 2, the joint 3, the O-ring 4, and the tapered ring 5 may be simply referred to as the radial direction.

At least the portion of the fitting 3 that connects to the pipe 2 is cylindrical. In the following description, the axial outside refers to the outside in the axial direction of the fitting 3, and the axial inside refers to the inside in the axial direction of the fitting 3. For the portion of the fitting-equipped pipe 1 that appears in Figures 1(a) and (b), the left side of Figures 1(a) and (b) is the axial outside, and the right side of Figures 1(a) and (b) is the axial inside.

The portion of the pipe 2 including the axial end 2a and the annular protrusion 11 is inserted from the outside in the axial direction into the joint internal space 12, which is the internal space of the joint 3. This allows communication between the pipe internal space 2c, which is the internal space of the pipe 2, and the joint internal space 12. The joint internal space 12 has first to sixth spatial portions 12a to 12f. The first to sixth spatial portions 12a to 12f are arranged adjacent to each other in this order from the inside to the outside in the axial direction. The pipe 2 inserted into the joint internal space 12 is located in the second to sixth spatial portions 12b to 12f. The first to sixth spatial portions 12a to 12f are all circular spaces when viewed in the axial direction.

The diameter of the first spatial portion 12a is smaller than the diameter of the portion of the pipe 2 where the annular protrusion 11 is not formed. The diameter of the second spatial portion 12b is approximately the same as the diameter of the portion of the pipe 2 where the annular protrusion 11 is not formed.

The diameter of the third spatial portion 12c is larger than the diameter of the second spatial portion 12b and smaller than the diameter of the annular protrusion 11. This forms a gap 13 between the wall surface 12c1 that defines the radial end of the third spatial portion 12c and the outer peripheral surface 2b of the pipe 2.

The portion between one end 2a of the pipe 2 and the annular protrusion 11 extends in the axial direction between the second spatial portion 12b and the third spatial portion 12c. The portion between one end 2a of the pipe 2 and the annular protrusion 11 is inserted into an O-ring 4. The O-ring 4 is disposed in the gap 13 in a state where it is elastically deformed in the radial direction, so that it is in close contact with the outer circumferential surface 2b of the pipe 2 and the wall surface 12c1 of the third spatial portion 12c. This prevents the fluid flowing through the pipe inner space 2c and the first spatial portion 12a from leaking out to the outside through the gap between one end 2a of the pipe 2 and the wall surface 12b1 that defines the axial inner end of the second spatial portion 12b, the gap between the outer circumferential surface 2b of the pipe 2 and the wall surface 12b2 that defines the radial end of the second spatial portion 12b, and the gap 13.

The diameter of the fourth spatial portion 12d is approximately the same as the diameter of the annular protrusion 11. The annular protrusion 11 is located within the fourth spatial portion 12d. The end face 11a on the axial inner side (one end 2a side) of the annular protrusion 11 contacts the wall surface 12d1 (contact surface of the present invention) that defines the axial inner end of the fourth spatial portion 12d. In addition, the outer peripheral surface 11b of the annular protrusion 11 contacts the wall surface 12d2 that defines the radial end of the fourth spatial portion 12d. In addition, as shown in FIG. 2(a), the outer peripheral surface 11b of the annular protrusion 11 is a knurled surface with repeated unevenness along the circumferential direction.

The diameter of the fifth spatial portion 12e at the inner end in the axial direction is the same as the diameter of the fourth spatial portion 12d. The diameter of the fifth spatial portion 12e increases toward the outside in the axial direction. As a result, the wall surface 12e1 that defines the radial end of the fifth spatial portion 12e is a tapered surface (the second tapered surface of the present invention) that is inclined with respect to the axial direction so as to become radially outward as it moves toward the outside in the axial direction (the further away it is from the annular protrusion 11).

The diameter of the sixth spatial portion 12f is larger than the diameter of the fourth spatial portion 12d and smaller than the diameter at the axially outer end of the fifth spatial portion 12e.

Since the diameters of the fourth to sixth spatial portions 12d to 12f are as described above, the wall surfaces that define the radial ends of the fourth to sixth spatial portions 12d to 12f are recessed radially outward and have engagement recesses 14 with tapered wall surfaces 12e1.

The tapered ring 5 is configured in an annular shape. The portion of the pipe 2 that is axially outer than the annular protrusion 11 (the portion farther from the one end 2a) is inserted into the tapered ring 5. The tapered ring 5 is press-fitted into the gap 16 between the portion of the outer circumferential surface 2b of the pipe 2 that is axially outer than the annular protrusion 11 and the wall surfaces 12d2, 12e1, 12f1 that define the radial ends of the fourth to sixth spatial portions 12d to 12f of the fitting 3. The axial position of the outer end face 5d of the tapered ring 5 is approximately the same as the axial position of the outer end face 3a of the fitting 3.

The portion of the outer peripheral surface 5a of the tapered ring 5 located in the fifth spatial portion 12e is a tapered surface 5b (the first tapered surface of the present invention) that is inclined with respect to the axial direction so as to move radially outward as it moves toward the axial outside (as it moves away from the annular protrusion 11). As a result, the portion of the tapered ring 5 located in the fifth spatial portion 12e has a larger diameter as it moves toward the axial outside. In addition, the diameter of the portion of the tapered ring 5 located in the sixth spatial portion 12f is approximately the same as the diameter of the sixth spatial portion 12f, and is larger than the diameter of the portion of the tapered ring 5 located in the fourth spatial portion 12d and smaller than the diameter at the outer end in the axial direction of the portion located in the fifth spatial portion 12e. As a result, an engagement protrusion 15 that protrudes radially and has a tapered surface 5b is formed on the outer peripheral surface 5a of the tapered ring 5.

The tapered ring 5 is fixed to the joint 3 by the engagement of the engagement convex portion 15 and the engagement concave portion 14. The inner axial end face 5c of the tapered ring 5 fixed to the joint 3 is in contact with the outer axial end face 11c of the annular convex portion 11 of the pipe 2. The tapered ring 5 presses the annular convex portion 11 of the pipe 2 against the wall surface 12d1 of the joint 3. As a result, the annular convex portion 11 is sandwiched between the tapered ring 5 and the wall surface 12d1 of the joint 3, and the pipe 2 is fixed to the joint 3 in the axial direction. Here, as shown in Figures 2(b) and (c), the end face 5c of the tapered ring 5 is a knurled surface with repeated concaves and convexes along the circumferential direction of the tapered ring 5.

The tapered surface 5b of the engaging protrusion 15 and the wall surface 12e1 of the engaging recess 14 are in close contact with each other. As shown in Figures 2(b) and (c), the tapered surface 5b of the engaging protrusion 15 is a knurled surface with repeated projections and recesses along the circumferential direction of the tapered ring 5.

2(d), adhesive 17 is interposed between the outer peripheral surface 5a of the tapered ring 5 and the wall surface (specifically, wall surface 12d2, 12e1, 12f1) that defines the radial end of the joint space 12. Adhesive 18 is interposed between the inner peripheral surface 5e of the tapered ring 5 and the outer peripheral surface 2b of the pipe 2. Note that in FIG. 2(d), the thickness of adhesive 17, 18 is shown large in order to make adhesive 17, 18 easier to understand, and the outer peripheral surface 5a of the tapered ring 5 and the wall surface that defines the radial end of the joint space 12 appear to be separated to a certain extent, but in reality, the outer peripheral surface 5a of the tapered ring 5 and the wall surface that defines the radial end of the joint space 12 are in close contact with each other via thin adhesive 17. Similarly, in FIG. 2(d), the inner circumferential surface 5e of the tapered ring 5 and the outer circumferential surface 2b of the pipe 2 appear to be separated to some extent, but in reality, the inner circumferential surface 5e of the tapered ring 5 and the outer circumferential surface 2b of the pipe 2 are in close contact with each other via a thin adhesive 18.

<Method of manufacturing a pipe with a fitting>
Next, a method for manufacturing the jointed pipe 1 will be described. To manufacture the jointed pipe 1, first, as shown in FIG. 3(a), the O-ring 4 is inserted into the portion between the axial end 2a of the pipe 2 and the annular protrusion 11, thereby attaching the O-ring 4 to the pipe 2 (seal member attachment process). Then, as shown in FIG. 3(b), the portion including the axial end 2a of the pipe 2 to which the O-ring 4 is attached and the annular protrusion 11 is inserted into the joint inner space 12 (insertion process). Then, the portion of the pipe 2 outside the annular protrusion 11 in the axial direction is inserted into the tapered ring 5 having an adhesive (not shown) applied to its outer peripheral surface 5a and inner peripheral surface 5e. Then, as shown in FIG. 3(c), a portion of the inner side of the tapered ring 5 in the axial direction is inserted into the gap 16, and pressure is applied to the tapered ring 5 from the outside in the axial direction, thereby pressing the tapered ring 5 having an adhesive (not shown) applied to its outer peripheral surface 5a and inner peripheral surface 5e into the gap 16 (press-in process). At this time, pressure is continued to be applied to the tapered ring 5 until the axial position of the end face 5d of the tapered ring 5 is substantially the same as the axial position of the end face 3a of the fitting 3. This causes the tapered ring 5 to be press-fitted to an appropriate position. Through the above steps, a fitting-equipped pipe 1 as shown in Figure 1(a) is manufactured.

＜Effects＞
In this embodiment, the tapered ring 5 is press-fitted into the joint 3 into which the pipe 2 is inserted, so that the engaging protrusion 15 of the tapered ring 5 and the engaging recess 14 of the joint 3 are engaged, and the annular protrusion 11 of the pipe 2 is sandwiched between the wall surface 12d1 of the joint 3 and the tapered ring 5, thereby fixing the pipe 2 and the joint 3. In addition, since the pipe 2 and the joint 3 are fixed by press-fitting the tapered ring 5 into the joint 3 into which the pipe 2 is inserted, no complicated process such as torque adjustment is required, unlike when the pipe 2 and the joint 3 are fixed by screwing in a fixing member. Therefore, the pipe 2 and the joint 3 can be easily fixed. In addition, by interposing adhesive 17 between the outer peripheral surface 5a of the tapered ring 5 and the wall surfaces (wall surfaces 12d2, 12e1, 12f1) that define the radial end of the space within the joint 12, relative movement between the joint 3 and the tapered ring 5 in the axial and circumferential directions, and relative rotation between the tapered ring 5 and the joint 3 are prevented, and foreign matter is prevented from entering between the outer peripheral surface 5a of the tapered ring 5 and the wall surfaces that define the radial end of the space within the joint 12.

In addition, in this embodiment, the engaging protrusion 15 has a tapered surface 5b inclined with respect to the axial direction so that the farther it is from the annular protrusion 11 in the axial direction, the more it is positioned radially outward of the tapered ring 5. Also, the engaging recess 14 faces the tapered surface 5b of the engaging protrusion 15 and has a wall surface 12e1 that is a tapered surface inclined with respect to the axial direction so that the farther it is from the annular protrusion 11 in the axial direction, the more it is positioned radially outward of the fitting 3. As a result, by pressing the tapered ring 5 into the fitting internal space 12 into which the pipe 2 is inserted, the engaging protrusion 15 and the engaging recess 14 are engaged, and the pipe 2 and the fitting 3 can be fixed as described above.

In addition, in this embodiment, adhesive 18 is interposed between the inner circumferential surface 5e of the tapered ring 5 and the outer circumferential surface 2b of the pipe 2. This prevents the tapered ring 5 and the pipe 2 from moving relative to each other in the axial and circumferential directions, and also prevents foreign matter from entering through the gap between the inner circumferential surface 5e of the tapered ring 5 and the outer circumferential surface 2b of the pipe 2.

In addition, in this embodiment, the tapered surface 5b of the engaging protrusion 15 and the wall surface 12e1 of the engaging recess 14 are in contact with each other, whereas the tapered surface 5b of the engaging protrusion 15, which is part of the outer peripheral surface 5a of the tapered ring 5, is a knurled surface with repeated unevenness along the circumferential direction of the tapered ring 5. As a result, the frictional force between the tapered surface 5b of the engaging protrusion 15 and the wall surface 12e1 of the engaging recess 14 is greater than when the tapered surface 5b is a surface without unevenness, making it difficult for the joint 3 and the tapered ring 5 to rotate relative to each other.

In addition, in this embodiment, the end face 5c of the tapered ring 5 and the end face 11c of the annular protrusion 11 are in contact with each other, whereas the end face 5c of the tapered ring 5 is a knurled surface with repeated unevenness along the circumferential direction of the tapered ring 5. As a result, the frictional force between the tapered ring 5 and the annular protrusion 11 is greater than when the end face 5c of the tapered ring 5 is a surface without unevenness, making it difficult for the pipe 2 and the tapered ring 5 to rotate relative to each other.

In addition, in this embodiment, the outer peripheral surface 11b of the annular convex portion 11 and the wall surface 12d2 of the fourth space portion 12d are in contact with each other, whereas the outer peripheral surface 11b of the annular convex portion 11 is a knurled surface with repeated unevenness along the circumferential direction. As a result, the frictional force between the outer peripheral surface 11b of the annular convex portion 11 and the wall surface 12d2 of the fourth space portion 12d is greater than when the outer peripheral surface 11b of the annular convex portion 11 is a surface without unevenness, making it difficult for the pipe 2 and the fitting 3 to rotate relative to each other.

<Modification>
Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various modifications are possible within the scope of the claims.

In the above embodiment, the entire tapered surface 5b of the outer peripheral surface 5a of the tapered ring 5 is a knurled surface, but this is not limited to this. For example, only a portion of the tapered surface 5b in the axial direction may be a knurled surface. Alternatively, for example, only a portion of the tapered surface 5b in the circumferential direction may be a knurled surface. Alternatively, for example, at least a portion of the outer peripheral surface 5a of the tapered ring 5 other than the tapered surface 5b may be a knurled surface.

Alternatively, the entire outer peripheral surface 5a of the tapered ring 5 may be a surface without any irregularities along the circumferential direction, and at least a portion of the wall surface 12e1 of the engagement recess 14 may be a knurled surface. Alternatively, both at least a portion of the outer peripheral surface 5a of the tapered ring 5 and at least a portion of the wall surface 12e1 of the engagement recess 14 may be knurled surfaces.

Alternatively, both the entire outer peripheral surface 5a of the tapered ring 5 and the entire portion of the wall surface defining the radial end of the joint internal space 12 that is in contact with the outer peripheral surface 5a of the tapered ring 5 may be surfaces that are smooth along the circumferential direction.

In the above embodiment, the entire end face 5c of the tapered ring 5 is a knurled surface, but this is not limited to this. For example, only a portion of the end face 5c of the tapered ring 5 in the radial direction may be a knurled surface. Alternatively, for example, only a portion of the end face 5c of the tapered ring 5 in the circumferential direction may be a knurled surface.

Also, the entire end face 5c of the tapered ring 5 may be a surface without any irregularities along the circumferential direction, and at least a portion of the end face 11c of the annular protrusion 11 may be a knurled surface. Alternatively, both at least a portion of the end face 5c of the tapered ring 5 and at least a portion of the end face 11c of the annular protrusion 11 may be knurled surfaces.

Alternatively, both the entire end face 5c of the tapered ring 5 and the entire end face 11c of the annular protrusion 11 may be surfaces that are free of irregularities along the circumferential direction.

In the above embodiment, the entire outer circumferential surface 11b of the annular convex portion 11 is a knurled surface, but this is not limited to this. For example, only a portion of the outer circumferential surface 11b of the annular convex portion 11 in the axial direction may be a knurled surface. Alternatively, for example, only a portion of the outer circumferential surface 11b of the annular convex portion 11 in the circumferential direction may be a knurled surface.

Also, the entire outer circumferential surface 11b of the annular protrusion 11 may be a surface without irregularities in the circumferential direction, and at least a portion of the portion of the wall surface 12d2 of the fourth space portion 12d that contacts the outer circumferential surface 11b of the annular protrusion 11 may be a knurled surface. Alternatively, both at least a portion of the outer circumferential surface 11b of the annular protrusion 11 and at least a portion of the portion of the wall surface 12d2 of the fourth space portion 12d that contacts the outer circumferential surface 11b of the annular protrusion 11 may be knurled surfaces.

Alternatively, both the entire outer peripheral surface 11b of the annular protrusion 11 and the entire portion of the wall surface 12d2 of the fourth spatial portion 12d that contacts the outer peripheral surface 11b of the annular protrusion 11 may be surfaces that are smooth along the circumferential direction.

In the above embodiment, adhesive 17 is interposed between the outer peripheral surface 5a of the tapered ring 5 and the wall surface (specifically, wall surfaces 12d2, 12e1, 12f1) that defines the radial end of the joint inner space 12, and adhesive 18 is interposed between the inner peripheral surface 5e of the tapered ring 5 and the outer peripheral surface 2b of the pipe 2, but this is not limited to the above. For example, adhesive 18 does not have to be interposed between the inner peripheral surface 5e of the tapered ring 5 and the outer peripheral surface 2b of the pipe 2.

In the above-described embodiment, the position of the outer end of the tapered ring 5 and the position of the outer end of the joint 3 are substantially the same in the axial direction, and the entire or almost entire tapered ring 5 is housed within the joint internal space 12, but this is not limited to the above.

As shown in Figures 4(a) to (c), a modified fitting pipe 101 is a fitting pipe 1 of the above-mentioned embodiment in which the tapered ring 5 is replaced with a tapered ring 102. The tapered ring 102 has a flange portion 103 in addition to the same configuration as the tapered ring 5. The flange portion 103 is located axially outward from the fitting 3. The diameter of the flange portion 103 is larger than the diameter of the sixth space portion 12f. The axially inner end face 103a of the flange portion 103 contacts the axially outer end face 3a of the fitting 3.

In this modified example, the pipe with fitting 101 can be formed in the same manner as in the above embodiment. However, in this modified example, when the tapered ring 102 is pressed into the gap 16, pressure is applied to the tapered ring 102 until the end face 103a of the flange portion 103 of the tapered ring 102 comes into contact with the end face 3a of the fitting 3. This allows the tapered ring 102 to be pressed into the appropriate position.

In addition, in the above-mentioned embodiment, the fixing member for fixing the pipe 2 and the fitting 3 is a tapered ring 5 with an engaging protrusion 15 having a tapered surface 5b, and an engaging recess 14 having a wall surface 12e1 that is a tapered surface, but this is not limited to this. The shapes of the engaging protrusion of the fixing member and the engaging recess of the fitting may be different from those of the above-mentioned embodiment, as long as the engaging protrusion formed on the fixing member and the engaging recess of the fitting 3 are engaged when the fixing member is pressed into the fitting internal space 12 into which the pipe 2 is inserted.

In addition, in the above embodiment, the O-ring 4 is used to seal between the pipe 2 and the fitting 3, but the pipe 2 and the fitting 3 may be sealed with an annular member other than the O-ring 4.

Reference Signs List 1: Pipe with fitting 2: Pipe 2a: One end 2c: Space inside pipe 3: Fitting 4: O-ring 5: Tapered ring 5a: Outer circumferential surface 5b: Tapered surface 5c: End surface 11: Annular convex portion 11a: End surface 12: Space inside fitting 12d1: Wall surface 13: Gap 14: Engaging recess 15: Engaging convex portion 16: Gap 17, 18: Adhesive 101: Pipe with fitting 102: Tapered ring

Claims (7)

Pipes and
A joint connected to the pipe;
a sealing member for sealing between the pipe and the joint;
A fixing member that fixes the pipe and the joint,
The pipe has an annular protrusion formed on its outer circumferential surface, the annular protrusion extending around the entire circumference of the pipe,
The joint is
a portion including one end of the pipe in the axial direction and the annular protrusion is inserted in the axial direction to form a fitting internal space that communicates with a pipe internal space, which is an internal space of the pipe;
a contact surface that is a part of a wall surface that defines the joint internal space, extends in a radial direction of the pipe, and comes into contact with an end surface of the annular protrusion on the one end side in the axial direction,
the sealing member is configured in an annular shape and is disposed in a gap between a portion of an outer circumferential surface of the pipe that is located between the one end of the pipe and the annular protrusion and a wall surface that defines an end of the fitting internal space in the radial direction,
the fixing member is configured in an annular shape, the pipe is inserted into the fixing member, the fixing member is positioned within the joint internal space of the pipe, and the fixing member is press-fitted into a gap between an outer circumferential surface of a portion of the fixing member that is farther from the one end of the pipe than the annular protrusion in the axial direction and a wall surface that defines the radial end of the joint internal space from the opposite side to the annular protrusion in the axial direction,
an end face of the fixing member on the annular protrusion side in the axial direction contacts the annular protrusion,
An engaging protrusion protruding in the radial direction is formed on an outer circumferential surface of the fixing member,
an engagement recess that is recessed in the radial direction and engages with the engagement protrusion of the press-fitted fixing member is formed on a wall surface that defines the radial end of the joint internal space;
A pipe with a fitting, characterized in that an adhesive is interposed between an outer peripheral surface of the fixing member and a wall surface that defines the radial end of the space within the fitting. the engaging protrusion has a first tapered surface that is inclined with respect to the axial direction so as to be positioned radially outward of the fixing member as the engaging protrusion moves away from the annular protrusion in the axial direction,
The fitting pipe as described in claim 1, characterized in that the engagement recess has a second tapered surface that faces the first tapered surface and is inclined with respect to the axial direction so that the further away from the annular convex portion in the axial direction, the more radially outward the fitting becomes. The pipe with fitting according to claim 1, characterized in that an adhesive is interposed between the inner circumferential surface of the fixing member and the outer circumferential surface of the pipe. The pipe with fitting according to claim 1, characterized in that at least a portion of the outer circumferential surface of the fixing member is a knurled surface with repeated projections and recesses along the circumferential direction. The pipe with fitting according to claim 1, characterized in that at least a portion of the end surface of the fixing member is a knurled surface with repeated projections and recesses along the circumferential direction. an outer circumferential surface of the annular protrusion contacts a wall surface that defines a radial end of the joint internal space,
2. The coupling-equipped pipe according to claim 1, wherein at least a portion of an outer circumferential surface of the annular convex portion is a knurled surface having repeated concaves and convexes along the circumferential direction. A method for manufacturing a jointed pipe according to claim 1,
a seal member attachment step of attaching the seal member to the pipe by inserting the seal member into a portion of the pipe between the one end and the annular protrusion;
an insertion step of inserting a portion of the pipe to which the seal member is attached, the portion including the one end and the annular protrusion, into the joint inner space;
a pressing step of pressing the fixing member, the fixing member having an outer peripheral surface coated with adhesive, into a gap between the outer peripheral surface of a portion of the pipe that is farther from the one end than the annular convex portion in the axial direction and a wall surface that defines the radial end of the space inside the fitting, from the opposite side to the annular convex portion in the axial direction.

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