Pipe with fittings and method for manufacturing pipe with fittings

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

[Technical Field]

[0001] The present invention relates to a piped pipe formed by connecting a pipe and a joint, and a method for manufacturing a piped pipe. [Background Art]

[0002] In Patent Document 1, a pipe joint to be connected to a connection pipe includes a joint main body into which the connection pipe is inserted, a pressing ring screwed into the joint main body, and a metal seal member incorporated inside the joint main body. The joint main body has female screw portions formed at both ends thereof, a downwardly inclined tapered surface formed from a terminal end portion toward a central portion, and a circumferential groove formed on the terminal end side of the joint main body. The pressing ring has a hexagonal nut-shaped head, a male screw portion screwed into the female screw portion of the joint main body, and a ring-shaped abutting portion formed on the terminal end side of the pressing ring. The metal seal member is a member that has a tapered surface against which the tapered surface of the joint main body abuts and is formed to have a wedge-shaped cross section. Further, protruding strip portions are formed along the circumferential direction on the tapered surface and the inner peripheral surface of the metal seal member.

[0003] In Patent Document 1, after a metal seal member is mounted inside the joint main body, the pressing ring is screwed into the joint main body, and the abutting portion formed on the tip end side of the pressing ring is abutted against the end face of the metal seal member. Next, the pressing ring is completely tightened. As a result, the tip end portion of the metal seal member enters the circumferential groove of the joint main body, the protruding strip portions are crushed, the tapered surface of the joint main body and the tapered surface of the metal seal member come into close contact with each other, and the inner peripheral surface of the metal seal member and the outer peripheral surface of the connection pipe come into close contact with each other, so that predetermined sealing performance can be obtained. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Unexamined Patent Publication No. 2008-89132 [Brief Summary of the Invention] [Problem to be Solved by the Invention]

[0005] In Patent Document 1, as described above, the thrust ring is screwed into the joint body and tightened, causing the tip of the metal seal member to enter the circumferential groove of the joint body, and the protruding portion to be crushed, so that the tapered surface of the joint body and the tapered surface of the metal seal member are in close contact, and the inner surface of the metal seal member and the outer surface of the connecting pipe are in close contact. In this case, torque control is necessary when tightening the thrust ring to prevent it from loosening after it has been screwed in, which makes the work complicated.

[0006] The object of the present invention is to provide a pipe with a fitting that can ensure sufficient sealing between the pipe and the fitting, and that can connect the pipe and the fitting in a simple process, and a method for manufacturing a pipe with a fitting. [Means for solving the problem]

[0007] The pipe with a joint of the present invention comprises a pipe, a joint connected to the pipe, a sealing member that seals the space between the pipe and the joint, and a fixing member that fixes the pipe and the joint, wherein an annular projection extending over its entire circumference is formed on the outer circumferential surface of the pipe, the joint is inserted in the axial direction into one end of the pipe in the axial direction and the portion including the annular projection, forming an internal joint space that communicates with the internal pipe space which is the internal space of the pipe, and has a contact surface that is part of the wall surface defining the internal joint space, extends radially in the pipe and contacts the end face on the one end side of the annular projection in the axial direction, and the sealing member is configured in an annular shape and has a portion of the outer circumferential surface of the pipe located between the one end of the pipe and the annular projection, and a wall surface that defines the radial end of the internal joint space. The fixing member is positioned in the gap between the pipes, and is configured in an annular shape, through which the pipe is inserted, located within the joint's internal space, and press-fitted from the opposite side of the annular projection in the axial direction into the gap between the outer circumferential surface of the pipe at a point further from one end of the pipe than the annular projection in the axial direction and the wall surface defining the radial end of the joint's internal space, with the end face of the fixing member on the annular projection side in the axial direction contacting the annular projection, an engaging projection projecting in the radial direction is formed on the outer circumferential surface of the fixing member, and an engaging recess is formed in the wall surface defining the radial end of the joint's internal space, which is radially recessed and engages with the engaging projection of the press-fitted fixing member, 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's internal space. [Effects of the Invention]

[0008] In this invention, when the fixing member is press-fitted, the engaging projection of the fixing member engages with the engaging recess of the joint, and the annular projection 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, since the pipe and the joint are fixed by press-fitting the fixing member, unlike when the pipe and the joint are fixed by screwing in the fixing member, complicated processes such as torque adjustment are unnecessary. Therefore, the pipe and the joint can be easily fixed. Furthermore, because an adhesive is interposed between the outer surface of the fixing member and the wall surface defining the radial end of the joint's internal space, it is possible to prevent the joint and the tapering from moving relative to each other in the axial and circumferential directions, and to prevent foreign matter from entering between the outer surface of the fixing member and the wall surface defining the radial end of the joint's internal space. [Brief explanation of the drawing]

[0009] [Figure 1] (a) is a cross-sectional view along the axial direction of a pipe with a joint according to an embodiment of the present invention, and (b) is a view of (a) exploded into its individual components. [Figure 2] (a) is a view of the pipe from the radial outside, (b) is a view of the tapering from the radial outside, (c) is a view of the tapering from the axial annular protrusion side, and (d) is an enlarged view of the area indicated by IID in Figure 1(a). [Figure 3] (a) is a diagram illustrating the process of attaching an O-ring to a pipe, (b) is a diagram illustrating the process of inserting the pipe with the O-ring attached into a fitting, and (c) is a diagram illustrating the process of press-fitting a tapered ring. [Figure 4] (a) is a cross-sectional view along the axial direction of a pipe with a fitting and a tapered ring having a flange, (b) is a view of the tapered ring having a flange from the radially outer side, and (c) is a view of the tapered ring having a flange from the axially annular protrusion side. [Modes for carrying out the invention]

[0010] Preferred embodiments of the present invention will be described below.

[0011] <Structure of pipes with fittings> As shown in Figures 1(a) and 1(b), the pipe with fittings 1 of this embodiment comprises a pipe 2, a fitting 3, an O-ring 4 (sealing member of the present invention), and a tapered ring 5 (fixing member of the present invention).

[0012] The pipe 2 is cylindrical in shape. An annular projection 11 is formed on the pipe 2. The annular projection 11 is formed near one end 2a in the axial direction of the pipe 2 and protrudes radially from the outer circumferential surface 2b of the pipe 2. The annular projection 11 also extends around the entire circumference of the outer circumferential surface 2b of the pipe 2. The annular projection 11 can be formed, for example, by bulging or cording. In this embodiment, since the axial directions of the pipe 2, joint 3, O-ring 4, and tapered ring 5 are in the same direction, these axial directions may be simply referred to as the axial direction below. Also, the radial direction of the pipe 2, joint 3, O-ring 4, and tapered ring 5 may be simply referred to as the radial direction below.

[0013] The joint 3 is configured in a cylindrical shape at least at the connection point with the pipe 2. In the following description, "outside in the axial direction" refers to the outside of the joint 3 in the axial direction, and "inside in the axial direction" refers to the inside of the joint 3 in the axial direction. For the part of the pipe 1 with the joint shown in Figures 1(a) and (b), the left side of Figures 1(a) and (b) is the outside in the axial direction, and the right side of Figures 1(a) and (b) is the inside in the axial direction.

[0014] The internal space 12 of the joint 3 is inserted from the outside in the axial direction into the joint space 12, which is the internal space of the joint 3. This creates communication between the internal space 2c of the pipe 2 and the internal space 12 of the joint. The internal space 12 of the joint has first to sixth spatial sections 12a to 12f. The first to sixth spatial sections 12a to 12f are arranged adjacently in this order from the inside to the outside in the axial direction. The pipe 2 inserted into the internal space 12 of the joint is located within the second to sixth spatial sections 12b to 12f. The first to sixth spatial sections 12a to 12f are all circular spaces when viewed in the axial direction.

[0015] The diameter of the first spatial portion 12a is smaller than the diameter of the portion of the pipe 2 where the annular projection 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 projection 11 is not formed.

[0016] 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. As a result, a gap 13 is formed between the wall surface 12c1 defining the radial end of the third spatial portion 12c and the outer circumferential surface 2b of the pipe 2.

[0017] The portion between one end 2a of the pipe 2 and the annular projection 11 extends axially across the second spatial portion 12b and the third spatial portion 12c. The portion between one end 2a of the pipe 2 and the annular projection 11 is inserted through the O-ring 4. The O-ring 4 is positioned within the gap 13 in a radially elastically deformed state, so as to be 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's internal space 2c and the first spatial portion 12a from leaking out through the gap between one end 2a of the pipe 2 and the wall surface 12b1 defining 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 defining the radial end of the second spatial portion 12b, and through the gap 13.

[0018] The diameter of the fourth space portion 12d is substantially the same as the diameter of the annular convex portion 11. The annular convex portion 11 is located within the fourth space portion 12d. An end surface 11a on the axially inner side (the one end 2a side) of the annular convex portion 11 is in contact with a wall surface 12d1 (the contact surface of the present invention) that defines the axially inner end of the fourth space portion 12d. Further, an outer circumferential surface 11b of the annular convex portion 11 is in contact with a wall surface 12d2 that defines the radially outer end of the fourth space portion 12d. Further, as shown in FIG. 2(a), the outer circumferential surface 11b of the annular convex portion 11 is a knurled surface in which irregularities are repeated along the circumferential direction.

[0019] The diameter at the axially inner end of the fifth space portion 12e is the same as the diameter of the fourth space portion 12d. Further, the diameter of the fifth space portion 12e increases toward the axially outer side. Accordingly, a wall surface 12e1 that defines the radially outer end of the fifth space portion 12e is a tapered surface (the second tapered surface of the present invention) inclined with respect to the axial direction so as to be directed radially outward as it goes toward the axially outer side (as it moves away from the annular convex portion 11).

[0020] The diameter of the sixth space portion 12f is larger than the diameter of the fourth space portion 12d and smaller than the diameter at the axially outer end of the fifth space portion 12e.

[0021] Since the diameters of the fourth to sixth space portions 12d to 12f are configured as described above, an engagement concave portion 14 that is recessed radially outward and has a tapered wall surface 12e1 is formed on the wall surface defining the radially outer ends of the fourth to sixth space portions 12d to 12f.

[0022] The taper ring 5 is formed in an annular shape. A portion of the pipe 2 that is located axially outward of the annular convex portion 11 (a portion away from the one end 2a) is inserted through the taper ring 5. Further, the taper ring 5 is press-fitted into a gap 16 between a portion of the outer circumferential surface 2b of the pipe 2 located axially outward of the annular convex portion 11 and wall surfaces 12d2, 12e1, 12f1 that define the radially outer ends of the fourth to sixth space portions 12d to 12f of the joint 3. Further, the axial position of the outer end surface 5d of the taper ring 5 is substantially the same as the axial position of the outer end surface 3a of the joint 3.

[0023] Among the outer peripheral surface 5a of the taper ring 5, the portion located inside the fifth space portion 12e is a tapered surface 5b (the first tapered surface of the present invention) which is inclined with respect to the axial direction so as to be directed radially outward as it goes axially outward (as it moves away from the annular convex portion 11). Accordingly, the diameter of the portion of the taper ring 5 disposed in the fifth space portion 12e increases as it goes axially outward. In addition, the diameter of the portion of the taper ring 5 disposed in the sixth space portion 12f is substantially the same as the diameter of the sixth space portion 12f, which is larger than the diameter of the portion of the taper ring 5 located in the fourth space portion 12d, and smaller than the diameter at the axially outer end of the portion located in the fifth space portion 12e. Accordingly, an engaging convex portion 15 that protrudes radially and has the tapered surface 5b is formed on the outer peripheral surface 5a of the taper ring 5.

[0024] The taper ring 5 is fixed to the joint 3 by the engagement between the engaging convex portion 15 and the engaging concave portion 14. In addition, the axially inner end surface 5c of the taper ring 5 fixed to the joint 3 is in contact with the axially outer end surface 11c of the annular convex portion 11 of the pipe 2. The taper ring 5 presses the annular convex portion 11 of the pipe 2 toward the wall surface 12d1 of the joint 3. Accordingly, the annular convex portion 11 is sandwiched between the taper 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 Figs. 2(b) and 2(c), the end surface 5c of the taper ring 5 is a knurled surface with repeated irregularities along the circumferential direction of the taper ring 5.

[0025] In addition, the tapered surface 5b of the engaging convex portion 15 is in close contact with the wall surface 12e1 of the engaging concave portion 14. Here, as shown in Figs. 2(b) and 2(c), the tapered surface 5b of the engaging convex portion 15 is a knurled surface with repeated irregularities along the circumferential direction of the taper ring 5.

[0026] Furthermore, as shown in Figure 2(d), adhesive 17 is interposed between the outer circumferential surface 5a of the tapered ring 5 and the wall surfaces (specifically, wall surfaces 12d2, 12e1, and 12f1) that define the radial end of the joint internal space 12. Adhesive 18 is also interposed between the inner circumferential surface 5e of the tapered ring 5 and the outer circumferential surface 2b of the pipe 2. Note that in Figure 2(d), the thickness of adhesives 17 and 18 is shown enlarged for clarity, making it appear as though the outer circumferential surface 5a of the tapered ring 5 and the wall surfaces defining the radial end of the joint internal space 12 are somewhat separated. However, in reality, the outer circumferential surface 5a of the tapered ring 5 and the wall surfaces defining the radial end of the joint internal space 12 are in close contact via a thin layer of adhesive 17. Similarly, in Figure 2(d), the inner surface 5e of the tapered ring 5 and the outer surface 2b of the pipe 2 appear to be somewhat separated, but in reality, the inner surface 5e of the tapered ring 5 and the outer surface 2b of the pipe 2 are in close contact via a thin adhesive 18.

[0027] <Method for manufacturing pipes with fittings> Next, the manufacturing method of the pipe with fitting 1 will be described. To manufacture the pipe with fitting 1, first, as shown in Figure 3(a), the O-ring 4 is attached to the pipe 2 by inserting it through the portion between one end 2a of the pipe 2 in the axial direction and the annular projection 11 (seal member attachment step). Subsequently, as shown in Figure 3(b), the portion of the pipe 2 including the axial end 2a and the annular projection 11 to which the O-ring 4 is attached is inserted into the joint space 12 (insertion step). Subsequently, the portion of the pipe 2 outside the annular projection 11 in the axial direction is inserted through a tapered ring 5, which has an adhesive (not shown) applied to its outer surface 5a and inner surface 5e. Then, as shown in Figure 3(c), a portion 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 to press-fit the tapered ring 5, which has an adhesive (not shown) applied to its outer surface 5a and inner surface 5e, into the gap 16 (press-fitting step). At this time, pressure is continuously applied to the tapered ring 5 until the axial position of the end face 5d of the tapered ring 5 is approximately the same as the axial position of the end face 3a of the joint 3. This presses the tapered ring 5 into the appropriate position. Through the above process, a pipe 1 with a joint, as shown in Figure 1(a), is manufactured.

[0028] <Effects> In this embodiment, the tapered ring 5 is press-fitted into the joint 3 into which the pipe 2 is inserted. This causes the engaging projection 15 of the tapered ring 5 to engage with the engaging recess 14 of the joint 3, and the annular projection 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 together. Furthermore, 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, there is no need for complicated processes such as torque adjustment, unlike when fixing the pipe 2 and the joint 3 by screwing in a fixing member. Therefore, the pipe 2 and the joint 3 can be easily fixed together. Furthermore, the presence of adhesive 17 between the outer surface 5a of the tapered ring 5 and the wall surfaces (wall surfaces 12d2, 12e1, 12f1) defining the radial ends of the joint internal space 12 prevents the joint 3 and the tapered ring 5 from moving relative to each other in the axial and circumferential directions, and prevents the tapered ring 5 and the joint 3 from rotating relative to each other. It also prevents foreign matter from entering between the outer surface 5a of the tapered ring 5 and the wall surfaces defining the radial ends of the joint internal space 12.

[0029] Furthermore, in this embodiment, the engaging projection 15 has a tapered surface 5b that is inclined with respect to the axial direction such that, as it moves away from the annular projection 11 in the axial direction, it is located radially outward of the tapered ring 5. The engaging recess 14 has a wall surface 12e1 that is a tapered surface inclined with respect to the axial direction, facing the tapered surface 5b of the engaging projection 15, and as it moves away from the annular projection 11 in the axial direction, it is located radially outward of the joint 3. As a result, by press-fitting the tapered ring 5 into the joint space 12 into which the pipe 2 is inserted, the engaging projection 15 and the engaging recess 14 are engaged, and the pipe 2 and the joint 3 can be fixed as described above.

[0030] Furthermore, in this embodiment, an 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.

[0031] Furthermore, in this embodiment, while the tapered surface 5b of the engaging projection 15 is in contact with the wall surface 12e1 of the engaging recess 14, the tapered surface 5b of the engaging projection 15, which is part of the outer peripheral surface 5a of the tapered ring 5, is a knurled surface with repeated irregularities along the circumferential direction of the tapered ring 5. As a result, the frictional force between the tapered surface 5b of the engaging projection 15 and the wall surface 12e1 of the engaging recess 14 is increased compared to the case where the tapered surface 5b is a smooth surface, making it more difficult for the joint 3 and the tapered ring 5 to rotate relative to each other.

[0032] Furthermore, in this embodiment, the end face 5c of the tapered ring 5 and the end face 11c of the annular projection 11 are in contact, while the end face 5c of the tapered ring 5 is a knurled surface with repeated irregularities along the circumferential direction of the tapered ring 5. As a result, the frictional force between the tapered ring 5 and the annular projection 11 is increased compared to the case where the end face 5c of the tapered ring 5 is a smooth surface, making it more difficult for the pipe 2 and the tapered ring 5 to rotate relative to each other.

[0033] Furthermore, in this embodiment, the outer circumferential surface 11b of the annular projection 11 is in contact with the wall surface 12d2 of the fourth space portion 12d, while the outer circumferential surface 11b of the annular projection 11 is a knurled surface with repeated irregularities along the circumferential direction. As a result, compared to the case where the outer circumferential surface 11b of the annular projection 11 is a smooth surface, the frictional force between the outer circumferential surface 11b of the annular projection 11 and the wall surface 12d2 of the fourth space portion 12d is increased, making it more difficult for the pipe 2 and the joint 3 to rotate relative to each other.

[0034] <Variation> Although preferred embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications are possible as long as they are within the scope of the claims.

[0035] In the embodiments described above, the entire tapered surface 5b of the outer circumferential surface 5a of the tapered ring 5 was 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 circumferential surface 5a of the tapered ring 5 other than the tapered surface 5b may be a knurled surface.

[0036] Alternatively, the entire outer circumferential surface 5a of the tapered ring 5 may be a smooth surface without irregularities along the circumferential direction, and at least a portion of the wall surface 12e1 of the engaging recess 14 may be a knurled surface. Or, at least a portion of the outer circumferential surface 5a of the tapered ring 5 and at least a portion of the wall surface 12e1 of the engaging recess 14 may both be knurled surfaces.

[0037] Alternatively, both the entire outer circumferential 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 circumferential surface 5a of the tapered ring 5 may be smooth surfaces without irregularities along the circumferential direction.

[0038] In the embodiments described above, the entire end face 5c of the tapered ring 5 was 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.

[0039] Alternatively, the entire end face 5c of the tapered ring 5 may be a smooth surface without irregularities along the circumferential direction, and at least a portion of the end face 11c of the annular projection 11 may be a knurled surface. Or, 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 projection 11 may both be knurled surfaces.

[0040] Alternatively, both the entire end face 5c of the tapered portion 5 and the entire end face 11c of the annular projection 11 may be smooth surfaces without irregularities along the circumferential direction.

[0041] In the embodiments described above, the entire outer circumferential surface 11b of the annular projection 11 was a knurled surface, but this is not limited to this. For example, only a portion of the outer circumferential surface 11b of the annular projection 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 projection 11 may be a knurled surface.

[0042] Alternatively, the entire outer circumferential surface 11b of the annular projection 11 may be a smooth surface without irregularities along the circumferential direction, and at least a portion of the wall surface 12d2 of the fourth spatial portion 12d that contacts the outer circumferential surface 11b of the annular projection 11 may be a knurled surface. Or, at least a portion of the outer circumferential surface 11b of the annular projection 11 and at least a portion of the wall surface 12d2 of the fourth spatial portion 12d that contacts the outer circumferential surface 11b of the annular projection 11 may both be knurled surfaces.

[0043] Alternatively, both the entire outer circumferential surface 11b of the annular projection 11 and the entire portion of the wall surface 12d2 of the fourth spatial portion 12d that contacts the outer circumferential surface 11b of the annular projection 11 may be smooth surfaces along the circumferential direction.

[0044] In the above-described embodiment, adhesive 17 was interposed between the outer circumferential surface 5a of the tapered ring 5 and the wall surfaces defining the radial ends of the joint internal space 12 (specifically, wall surfaces 12d2, 12e1, 12f1), and adhesive 18 was interposed between the inner circumferential surface 5e of the tapered ring 5 and the outer circumferential surface 2b of the pipe 2, but the embodiment is not limited to this. For example, adhesive 18 does not need to be interposed between the inner circumferential surface 5e of the tapered ring 5 and the outer circumferential surface 2b of the pipe 2.

[0045] 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 approximately the same in the axial direction, and the entire or almost entire tapered ring 5 is housed within the joint space 12, but it is not limited to this.

[0046] As shown in Figures 4(a) to 4(c), one modified example of the pipe with fitting 101 is obtained by replacing the tapered ring 5 with a tapered ring 102 in the pipe with fitting 1 of the above-described embodiment. The tapered ring 102 has the same configuration as the tapered ring 5, in addition to having a flange portion 103. 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 inward end face 103a of the flange portion 103 is in contact with the axially outward end face 3a of the fitting 3.

[0047] In this modified example, the pipe 101 with a joint can be formed using the same procedure as in the embodiment described above. However, in this modified example, when pressing the tapered ring 102 into the gap 16, pressure is continuously applied to the tapered ring 102 until the end face 103a of the flange portion 103 of the tapered ring 102 contacts the end face 3a of the joint 3. This ensures that the tapered ring 102 is pressed into the appropriate position.

[0048] Furthermore, in the above-described embodiment, the fixing member for fixing the pipe 2 and the joint 3 had a tapered ring 5 with an engaging projection 15 having a tapered surface 5b, and an engaging recess 14 having a wall surface 12e1 which is a tapered surface, but it is not limited to this. The shapes of the engaging projection of the fixing member and the engaging recess of the joint 3 may differ from those in the above-described embodiment, as long as the engaging projection formed on the fixing member and the engaging recess of the joint engage when the fixing member is press-fitted into the joint space 12 into which the pipe 2 is inserted.

[0049] Furthermore, in the above-described embodiment, the space between the pipe 2 and the joint 3 is sealed by the O-ring 4, but the space between the pipe 2 and the joint 3 may be sealed by an annular member other than the O-ring 4. [Explanation of Symbols]

[0050] 1: Pipe with fittings 2: Pipe 2a: one end 2c: Space inside the pipe 3: Fittings 4: O-ring 5: Tapering 5a: Outer surface 5b: Tapered surface 5c: End face 11: Ring-shaped protrusion 11a: End face 12: Space inside the joint 12d1: Wall 13: Gap 14: Engagement recess 15: Engagement convex part 16: Gap 17, 18: Adhesive 101: Pipe with fittings 102: Tapering

Claims

1. A pipe and A fitting connected to the aforementioned pipe, A sealing member that seals the space between the pipe and the fitting, The system includes a fixing member for fixing the pipe and the joint, An annular projection extending along its entire circumference is formed on the outer surface of the aforementioned pipe. The aforementioned joint is, The portion of the pipe including one end and the annular protrusion in the axial direction is inserted in the axial direction, forming a joint internal space that communicates with the internal space of the pipe, which is the internal space of the pipe. It is a part of the wall surface defining the internal space of the joint, and has a contact surface that extends in the radial direction of the pipe and contacts the end face on one end of the annular protrusion in the axial direction, The sealing member is configured in an annular shape and is positioned in the gap between the portion of the outer surface of the pipe located between the one end of the pipe and the annular projection and the wall surface defining the radial end of the internal space of the joint. The fixing member is annular in shape, through which the pipe is inserted, located within the joint's internal space, and press-fitted from the opposite side of the annular protrusion in the axial direction into the gap between the outer circumferential surface of the pipe at a distance from one end of the pipe than the annular protrusion in the axial direction and the wall surface defining the radial end of the joint's internal space. The end face of the fixing member on the side of the annular projection in the axial direction contacts the annular projection, An engaging projection that protrudes in the radial direction is formed on the outer circumferential surface of the fixing member. An engagement recess is formed on the wall surface defining the radial end of the joint's internal space, which is radially recessed and engages with the engagement projection of the press-fitted fixing member. A pipe with a joint, characterized in that an adhesive is interposed between the outer surface of the fixing member and the wall surface defining the radial end of the joint's internal space.

2. The engaging projection has a first tapered surface that is inclined with respect to the axial direction, such that it is located radially outward of the fixing member as it moves away from the annular projection in the axial direction. The pipe with a joint according to claim 1, characterized in that the engaging recess has a second tapered surface that is inclined with respect to the axial direction, facing the first tapered surface, and is located radially outward of the joint as it moves away from the annular protrusion in the axial direction.

3. The pipe with a joint 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.

4. The pipe with a joint according to claim 1, characterized in that at least a portion of the outer surface of the fixing member is a knurled surface in which irregularities are repeated along the circumferential direction.

5. The pipe with a joint according to claim 1, characterized in that at least a portion of the end face of the fixing member is a knurled surface in which the irregularities are repeated along the circumferential direction.

6. The outer circumferential surface of the annular protrusion is in contact with the wall surface that defines the radial end of the joint's internal space. The pipe with a joint according to claim 1, characterized in that at least a portion of the outer surface of the annular protrusion is a knurled surface in which the irregularities are repeated along the circumferential direction.

7. A method for manufacturing a pipe with a fitting according to claim 1, A sealing member installation step involves inserting the portion of the pipe between one end and the annular projection into the sealing member to attach the sealing member to the pipe, An insertion step of inserting the portion of the pipe to which the sealing member is attached, including the one end and the annular projection, into the space inside the joint, A method for manufacturing a pipe with a fitting, comprising: a press-fitting step of press-fitting the fixing member, which has adhesive applied to its outer surface, into the gap between the outer surface of the pipe in the axial direction of the pipe, in a portion of the pipe further from one end than the annular projection, and the wall surface defining the radial end of the internal space of the fitting, from the side opposite to the annular projection in the axial direction.

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