Pipe joint structure and method for constructing a pipe joint structure

Abstract

The pipe fitting of the present invention comprises: an outer fitting pipe having a first inner circumferential surface on one axial side and a second inner circumferential surface on the other axial side, wherein the outer circumferential surface of a pipe is fitted from one axial side to the first inner circumferential surface; an inner fitting pipe having a first outer circumferential surface on one axial side that fits from the other axial side to the inner circumferential surface of the pipe, and a second outer circumferential surface on the other axial side that fits from the other axial side to the second inner circumferential surface, the end on the other axial side being connected to a fluid device; an annular sealing member disposed on the first outer circumferential surface to seal between the first outer circumferential surface and the inner circumferential surface of the pipe; a first limiting portion that fits with the first inner circumferential surface via the outer circumferential surface of the pipe, thereby limiting relative movement of the pipe relative to the first inner circumferential surface towards one axial side; and a second limiting portion that fits with the second inner circumferential surface via the second outer circumferential surface, thereby limiting relative movement of the inner fitting pipe relative to the second inner circumferential surface towards the other axial side.

Description

Technical Field

[0001] This invention relates to a pipe fitting structure and a method for constructing the pipe fitting structure. This application claims priority to Japanese Application No. 2023-198949, filed November 24, 2023, and International Patent Application PCT / JP2024 / 013055, filed March 29, 2024, and incorporates the entire contents of the aforementioned Japanese application and international patent application. Background Technology

[0002] In manufacturing apparatuses in various technical fields such as semiconductor manufacturing, medical or pharmaceutical manufacturing, a pipe fitting as described in Patent Document 1 is known as a connection structure for connecting pipes and other piping to fluid devices and other fluid equipment. The pipe fitting of Patent Document 1 has an inner ring, a fitting body, and a connecting nut. The inner ring is installed on the inner circumference of the end of the pipe, the fitting body is installed on the outer circumference of the end of the pipe, and the connecting nut has an internal thread that is fastened to the external thread formed on the outer circumference of the fitting body.

[0003] When connecting the pipe to the fitting, the operator presses the inner ring into the inner circumference of the pipe end and installs the fitting body onto the outer circumference of the pipe end, then tightens the internal thread of the pipe nut onto the external thread of the fitting body. This ensures a tight seal between the fitting body and the pipe and prevents the pipe end from being pulled out of the fitting body.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2021-195959 Summary of the Invention

[0005] For the aforementioned pipe fittings, tools such as wrenches are required to tighten the pipe nut to the fitting body. Therefore, in confined spaces, it is sometimes impossible to tighten the pipe nut using tools. Furthermore, torque management is necessary to ensure the pipe nut is tightened within the appropriate range. This torque management requires skill, thus limiting the number of operators capable of tightening the pipe nut.

[0006] The purpose of this invention is to provide a pipe fitting structure and a construction method for connecting pipes without the use of tools.

[0007] (1) The pipe fitting structure of the present invention is used to connect a pipe to a flow path formed in a fluid device. The pipe fitting structure comprises: an outer fitting pipe having a first inner circumferential surface on one axial side and a second inner circumferential surface on the other axial side, the outer circumferential surface of the pipe fitting from the axial side toward the first inner circumferential surface; an inner fitting pipe having a first outer circumferential surface on one axial side that fits with the inner circumferential surface of the pipe from the other axial side, and a second outer circumferential surface on the other axial side that fits with the second inner circumferential surface of the outer fitting pipe from the other axial side, the end on the other axial side being connected to the fluid... Equipment connection; an annular sealing component disposed on the first outer peripheral surface of the inner connector tube, sealing the first outer peripheral surface between the first outer peripheral surface and the inner peripheral surface of the pipe; a first limiting portion, which engages with the first inner peripheral surface of the outer connector tube via the outer peripheral surface of the pipe, thereby limiting the relative movement of the pipe relative to the first inner peripheral surface towards one side of the axial direction; and a second limiting portion, which engages with the second inner peripheral surface of the outer connector tube via the second outer peripheral surface of the inner connector tube, thereby limiting the relative movement of the inner connector tube relative to the second inner peripheral surface towards the other side of the axial direction.

[0008] According to the pipe fitting structure of the present invention, by inserting the pipe from one axial side toward the inner circumferential side of the outer fitting pipe, the outer circumferential surface of the pipe is fitted with the first inner circumferential surface of the outer fitting pipe. Thus, the relative movement of the pipe relative to the first inner circumferential surface of the outer fitting pipe toward one axial side can be restricted by the first limiting portion. In this state, by inserting the inner fitting pipe from the other axial side toward the inner circumferential side of the outer fitting pipe, the first outer circumferential surface of the inner fitting pipe is fitted with the inner circumferential surface of the pipe, and the second outer circumferential surface of the inner fitting pipe is fitted with the second inner circumferential surface of the outer fitting pipe. Thus, the first outer circumferential surface of the inner fitting pipe and the inner circumferential surface of the pipe are sealed by a sealing member, and the relative movement of the inner fitting pipe relative to the second inner circumferential surface of the outer fitting pipe toward the other axial side can be restricted by the second limiting portion. Therefore, after the operator inserts the piping into the inner circumference of the outer connector pipe from one axial side, the operator can easily connect the piping to the pipe fitting structure without using tools by simply inserting the inner connector pipe into the inner circumference of the outer connector pipe from the other axial side.

[0009] (2) From another viewpoint, the pipe fitting structure of the present invention is used to connect piping to a flow path formed in a fluid device. The pipe fitting structure comprises: an outer fitting pipe having a first inner circumferential surface on one axial side and a second inner circumferential surface on the other axial side, the outer circumferential surface of the piping fitting into the first inner circumferential surface; an inner fitting pipe having a first outer circumferential surface on one axial side that fits into the inner circumferential surface of the piping from the other axial side, and a second outer circumferential surface on the other axial side that fits into the second inner circumferential surface of the outer fitting pipe from the other axial side, the end on the other axial side being connected to the fluid device; and an annular joint. A sealing component is disposed on the first outer peripheral surface of the inner connector tube to seal between the first outer peripheral surface and the inner peripheral surface of the pipe; a first limiting portion is fitted with the first inner peripheral surface of the outer connector tube through the outer peripheral surface of the pipe to limit the relative movement of the pipe relative to the first inner peripheral surface towards one side of the axial direction; and a second limiting portion is fitted with the second outer peripheral surface of the inner connector tube to the second inner peripheral surface of the outer connector tube to limit the relative movement of the inner connector tube relative to the second inner peripheral surface towards the other side of the axial direction, the outer connector tube being composed of a plurality of segments divided circumferentially.

[0010] According to the pipe fitting structure of the present invention, by arranging the axial side of a plurality of segments constituting the outer fitting tube on the radially outer side of the outer peripheral surface of the piping, these plurality of segments are combined circumferentially, thereby fitting the outer peripheral surface of the piping with the first inner peripheral surface of the outer fitting tube. Thus, the relative movement of the piping with respect to the first inner peripheral surface of the outer fitting tube towards one axial side can be restricted by the first limiting portion. In this state, by inserting the inner fitting tube from the other axial side toward the inner peripheral side of the outer fitting tube, the first outer peripheral surface of the inner fitting tube fits with the inner peripheral surface of the piping, and the second outer peripheral surface of the inner fitting tube fits with the second inner peripheral surface of the outer fitting tube. Thus, the first outer peripheral surface of the inner fitting tube and the inner peripheral surface of the piping are sealed by a sealing member, and the relative movement of the inner fitting tube with respect to the second inner peripheral surface of the outer fitting tube towards the other axial side can be restricted by the second limiting portion. Therefore, after the operator fits the outer circumferential surface of the piping with the inner circumferential side of the outer connector pipe, the piping can be easily connected to the pipe fitting structure without the use of tools simply by inserting the inner connector pipe into the inner circumferential side of the outer connector pipe from the other axial side.

[0011] Furthermore, in the pipe fitting structure described in (1) above, for example, when a portion of the first limiting part protrudes radially inward from the inner circumference of the outer fitting pipe, it is necessary to deform the insertion end of the pipe while inserting it into the inner circumference of the outer fitting pipe from the axial side. Therefore, it is impossible to connect a pipe made of a non-deformable material such as metal to the pipe fitting structure. In contrast, in the pipe fitting structure described in (2) above, by assembling multiple segments circumferentially on the radially outer side of the outer circumferential surface of the pipe as described above, the outer circumferential surface of the pipe can be fitted with the first inner circumferential surface of the outer fitting pipe without being obstructed by the portion of the first limiting part 5. Therefore, when fitting the outer circumferential surface of the pipe with the first inner circumferential surface of the outer fitting pipe, it is not necessary to deform the pipe, and thus, even a pipe made of a non-deformable material can be connected to the pipe fitting structure.

[0012] (3) In the pipe fitting structure of (1) or (2), the first limiting part preferably has an engaging protrusion provided on one of the first inner peripheral surface of the outer fitting pipe and the outer peripheral surface of the pipe and an engaging groove provided on the other, thereby limiting the relative movement of the pipe by engaging the engaging protrusion with the engaging groove.

[0013] In this case, the first limiting part is a structure in which the engaging protrusion engages with the engaging groove, thus reliably limiting the relative movement of the piping with respect to the external connector pipe.

[0014] (4) In the pipe fitting structure of (3), it is preferable that the engagement groove is located on the other side of the axial direction, which is closer to the sealing member.

[0015] For example, if the engagement groove of the first limiting part is formed through the thickness direction of the pipe, there is a concern that fluid in the pipe may leak from the engagement groove through the gap between the pipe and the external connector pipe to the axial side of the external connector pipe. Therefore, in addition to the sealing member, a sealing structure to suppress the leakage of the fluid is required. However, in (3) above, the engagement groove is located further to the other side of the axial direction than the sealing member that seals between the pipe and the external connector pipe. Therefore, the leakage of fluid in the pipe from the engagement groove to the axial side of the external connector pipe can be suppressed by the sealing member. As a result, there is no need to provide the sealing structure separately, and the structure of the pipe connector can be simplified.

[0016] (5) In any of the pipe fitting structures in (1) to (4), the second limiting part preferably has a hook portion integrally provided on one of the second inner peripheral surface of the outer fitting pipe and the second outer peripheral surface of the inner fitting pipe, and a hook groove provided on the other, thereby limiting the relative movement of the inner fitting pipe by hooking the hook portion onto the hook groove.

[0017] In this configuration, the second limiting part is a structure in which the hook part is hooked into the hook groove, thus reliably limiting the relative movement of the inner connector tube relative to the outer connector tube. Furthermore, since the hook part is integrally provided on the second outer circumferential surface of the inner connector tube or the second inner circumferential surface of the outer connector tube, the structure of the pipe connector can be simplified.

[0018] (6) In any of the pipe fitting structures in (1) to (4), the second limiting part preferably has: a locking part which is separately disposed from the outer fitting tube and is capable of protruding radially inward more than the second inner peripheral surface; and a locking groove which is disposed on the second outer peripheral surface of the inner fitting tube and engages with the locking groove by the locking part protruding radially inward, thereby restricting the relative movement of the inner fitting tube.

[0019] In this case, the second limiting part is a structure in which the locking part hooks onto the locking groove, thus reliably limiting the relative movement of the inner connector tube relative to the outer connector tube.

[0020] (7) The construction method of the pipe fitting structure of the present invention is a construction method for connecting the pipe in the pipe fitting structure of (1) for connecting the pipe to the flow path formed in the fluid device. The construction method of the pipe fitting structure includes the following steps in sequence: inserting the pipe into the inner circumferential side of the outer fitting pipe from the axial side of the outer fitting pipe, fitting the outer circumferential surface of the pipe with the first inner circumferential surface of the outer fitting pipe; and inserting the inner fitting pipe into the inner circumferential side of the outer fitting pipe from the other axial side of the outer fitting pipe, fitting the first outer circumferential surface of the inner fitting pipe with the inner circumferential surface of the pipe, and fitting the second outer circumferential surface of the inner fitting pipe with the second inner circumferential surface of the outer fitting pipe.

[0021] The construction method of the pipe joint structure according to the present invention achieves the same effect as the pipe joint structure described above (1).

[0022] (8) Preferably, the pipe fitting structure of (2) also has a fixing part that fixes the adjacent segments together in the circumferential direction.

[0023] In this case, the adjacent circumferential segments of the external connector pipe are fixed to each other by the fixing part, thereby preventing each segment of the external connector pipe from falling off from the outer circumferential surface of the piping and the second outer circumferential surface of the internal connector pipe.

[0024] (9) In the pipe fitting construction of (8), the fixing part preferably has a protrusion protruding from one of the circumferentially adjacent segments toward the other segment and a recess formed in the other segment, wherein the protrusion is embedded in the recess, so that the circumferentially adjacent segments are fixed to each other.

[0025] In this case, the fixing part is a structure in which the protrusion is embedded in the recess, so that adjacent segments along the circumferential direction can be reliably fixed to each other.

[0026] (10) The construction method of the pipe fitting structure of the present invention from another viewpoint is a construction method for connecting the pipe in the pipe fitting structure of (2) for connecting the pipe to the flow path formed in the fluid device. The construction method of the pipe fitting structure includes the following steps in sequence: by arranging the axial side of each of the plurality of the segments on the radially outer side of the outer peripheral surface of the pipe, circumferentially assembling the plurality of the segments, thereby fitting the outer peripheral surface of the pipe to the first inner peripheral surface of the outer fitting pipe; and inserting the inner fitting pipe relative to the inner peripheral side of the outer fitting pipe from the other axial side of the outer fitting pipe, fitting the first outer peripheral surface of the inner fitting pipe to the inner peripheral surface of the pipe, and fitting the second outer peripheral surface of the inner fitting pipe to the second inner peripheral surface of the outer fitting pipe.

[0027] The construction method of the pipe joint structure according to the present invention achieves the same effect as the pipe joint structure described above (2).

[0028] The effects of the invention

[0029] According to the present invention, piping can be easily connected to the pipe fitting structure without the use of tools. Attached Figure Description

[0030] Figure 1 This is a perspective view showing the pipe fitting structure according to the first embodiment.

[0031] Figure 2 yes Figure 1 A-direction view.

[0032] Figure 3 yes Figure 2 BOC cross-section diagram.

[0033] Figure 4 This is an oblique view of the external connector pipe when viewed from the axial side.

[0034] Figure 5 This is an oblique view of the external connector pipe when viewed from the other side of the axial direction.

[0035] Figure 6This is a perspective view of the internal connector pipe.

[0036] Figure 7 This is a cross-sectional oblique view showing the first limiting part.

[0037] Figure 8 This is a perspective view of the large groove of the hook groove in the second limiting part.

[0038] Figure 9 yes Figure 1 A diagram illustrating the construction method of the pipe joint structure.

[0039] Figure 10 yes Figure 1 The diagram illustrates the construction method for the pipe joint structure.

[0040] Figure 11 yes Figure 1 A diagram illustrating the construction method of the pipe joint structure.

[0041] Figure 12 yes Figure 1 A diagram illustrating the construction method of the pipe joint structure.

[0042] Figure 13 yes Figure 1 A diagram illustrating the construction method of the pipe joint structure.

[0043] Figure 14 yes Figure 1 A diagram illustrating the construction method of the pipe joint structure.

[0044] Figure 15 This is a perspective view showing the pipe fitting structure according to the second embodiment.

[0045] Figure 16 This is a diagram showing the external connector tube of the second embodiment viewed from the other side of the axial direction.

[0046] Figure 17 This indicates that the guided part of the locking rod is from... Figure 16 The diagram shows the state after sliding along the guide surface.

[0047] Figure 18 yes Figure 15 A diagram illustrating the construction method of the pipe joint structure.

[0048] Figure 19 yes Figure 15 A diagram illustrating the construction method of the pipe joint structure.

[0049] Figure 20 yes Figure 15 The diagram illustrates the construction method for the pipe joint structure.

[0050] Figure 21 yes Figure 15 The diagram illustrates the construction method for the pipe joint structure.

[0051] Figure 22 This is a perspective view showing the pipe fitting structure according to the third embodiment.

[0052] Figure 23 This is a diagram showing the external connector tube of the third embodiment viewed from the other side of the axial direction.

[0053] Figure 24 From Figure 23 The diagram shows the external connector tube of the third embodiment viewed from the bottom.

[0054] Figure 25 This is a perspective view showing the locking bar of the third embodiment.

[0055] Figure 26 This indicates that the stop bar is from Figure 23 The diagram shows the state after the state has moved downwards.

[0056] Figure 27 This is a cross-sectional perspective view of the inner connector tube in the third embodiment.

[0057] Figure 28 This is a perspective view showing the pipe fitting structure according to the fourth embodiment.

[0058] Figure 29 This is a perspective view showing the state of the external connector tube after disassembly according to the fourth embodiment.

[0059] Figure 30 yes Figure 28 The diagram illustrates the construction method for the pipe joint structure.

[0060] Figure 31 This is a perspective view showing the pipe fitting structure according to the fifth embodiment.

[0061] Figure 32 This is a perspective view showing the state after the external connector tube and fixing part of the fifth embodiment have been disassembled.

[0062] Figure 33 yes Figure 31 The diagram illustrates the construction method for the pipe joint structure.

[0063] Figure 34 This is a cross-sectional perspective view showing a modified example of the first limiting part.

[0064] Figure 35 This is a cross-sectional perspective view showing other variations of the first limiting part. Detailed Implementation

[0065] Next, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0066] [First Implementation]

[0067] <Structure of pipe fittings>

[0068] Figure 1 This is a perspective view showing the pipe fitting structure 1 according to the first embodiment. Figure 2 yes Figure 1 A-direction view. Figure 3 yes Figure 2 BOC cross-section diagram. Figures 1 to 3 In this embodiment, the pipe fitting structure 1 is used, for example, in a hydrogen carrier manufacturing apparatus, to connect a easily deformable synthetic resin pipe (piping) 72 to the flow path 71 of a fluid device (fluid equipment) 70 through which a corrosive fluid (transport fluid) flows. The pipe fitting structure 1 has an outer fitting pipe 2, an inner fitting pipe 3, and a sealing component 4.

[0069] In this invention, the direction along the axis O of the pipe fitting structure 1 is referred to as the axial direction of the pipe fitting structure 1, or simply "axial direction". For convenience, Figure 3 The right side is called the "axial side". Figure 3 The left side is referred to as the "other side of the axis". In addition, the direction orthogonal to axis O is the radial direction of pipe fitting structure 1, simply referred to as "radial". The direction of rotation about axis O is the circumferential direction of pipe fitting structure 1, simply referred to as "circumferential".

[0070] The external connector tube 2 is formed into a cylindrical shape from a synthetic resin material such as PVC, PP, PE, or fluoropolymer (PFA or PTFE). The outer circumferential surface 22 of the external connector tube 2 has a uniform diameter throughout its axial length. The inner circumferential surface 21 of the external connector tube 2 has a first inner circumferential surface 211 formed on one axial side and a second inner circumferential surface 212 formed on the other axial side. The diameter of the second inner circumferential surface 212 is larger than that of the first inner circumferential surface 211. The outer circumferential surface 72b of the end of the tube 72 is fitted onto the first inner circumferential surface 211 from its axial side.

[0071] A recess 213 is formed on the first inner peripheral surface 211. A pair of recesses 213 are formed at equal intervals (180° intervals) along the circumference of the first inner peripheral surface 211 (see reference). Figure 2 Each recess 213 is formed to extend the entire axial length of the first inner peripheral surface 211. The bottom surface of each recess 213 is formed to be coplanar with the second inner peripheral surface 212.

[0072] Figure 4 This is an oblique view of the external connector pipe 2 viewed from the axial side. Figure 5 This is an oblique view of the external connector pipe 2 as seen from the opposite axial side. Figures 2 to 5In this structure, slits 23 are formed on both sides of the circumferential direction of each recess 213. Each slit 23 cuts into the middle part (middle part of recess 213) on one side of the axial direction from the end face on the other side of the outer connector tube 2. Through each slit 23, the second inner circumferential surface 212 is divided circumferentially.

[0073] The external connector tube 2 has a flexible piece 24 at each slit 23, between a pair of circumferentially adjacent slits 23. Each flexible piece 24 has a base end 24a on one axial side and a front end 24b on the other axial side. The front end 24b is capable of radially flexing about the base end 24a as a fulcrum.

[0074] Figure 6 This is a perspective view showing the internal connector pipe 3. Figure 3 and Figure 6 In the inner connector tube 3, a connecting passage 3a for the flow of the conveyed fluid is formed axially. In this embodiment, since the conveyed fluid is a corrosive fluid, the inner connector tube 3 is made of a corrosion-resistant material (e.g., fluoropolymer or titanium palladium). The inner connector tube 3 has an annular portion 31 as one end on its axial side and a cylindrical portion 32 extending axially from the inner circumferential end of the annular portion 31.

[0075] The diameter of the outer peripheral surface 31b of the annular portion 31 is larger than the outer peripheral surface 22 of the outer connector tube 2. The annular portion 31 is connected to the fluid device 70 so that the connecting passage 3a is connected to the flow path 71 of the fluid device 70. The diameter of the inner peripheral surface 31a of the annular portion 31 is approximately the same as the inner peripheral surface of the flow path 71.

[0076] The inner circumferential surface 33 of the cylindrical portion 32 has the same diameter throughout the axial direction, and it has the same diameter as the inner circumferential surface 31a of the annular portion 31. The outer circumferential surface 34 of the cylindrical portion 32 has a first outer circumferential surface 341 formed on one axial side and a second outer circumferential surface 342 formed on the other axial side. The diameter of the second outer circumferential surface 342 is larger than that of the first outer circumferential surface 341. The first outer circumferential surface 341 engages with the inner circumferential surface 72a of the end of the tube 72 from one axial side. The second outer circumferential surface 342 engages with the second inner circumferential surface 212 of the outer connector tube 2 from the other axial side.

[0077] The inner circumferential surface 33 of the cylindrical portion 32 also has an annular conical surface 343 formed between the first outer circumferential surface 341 and the second outer circumferential surface 342. The conical surface 343 is inclined in a manner that gradually expands in diameter from one end of its axial direction toward the other end of its axial direction.

[0078] The sealing component 4 is an annular component that prevents leakage of the conveyed fluid between the first outer peripheral surface 341 of the inner connector pipe 3 and the inner peripheral surface 72a of the end of the pipe 72. Like the inner connector pipe 3, the sealing component 4 is formed of a corrosion-resistant material. In this embodiment, the sealing component 4 is, for example, an O-ring.

[0079] A sealing member 4 is disposed on the first outer peripheral surface 341 of the inner connector tube 3. Specifically, an annular groove 344 is formed at the axial end of the first outer peripheral surface 341, and the sealing member 4 is embedded and fixed in the groove 344. As described above, the outer peripheral surface of the sealing member 4 is in close contact with the inner peripheral surface 72a of the end of the tube 72 by fitting the first outer peripheral surface 341 of the inner connector tube 3 with the inner peripheral surface 72a of the end of the tube 72. Thus, the sealing member 4 seals the space between the first outer peripheral surface 341 of the inner connector tube 3 and the inner peripheral surface 72a of the end of the tube 72.

[0080] Pipe 72 sometimes needs to be adjusted due to the fluid pressure or thermal expansion of the fluid being transported. Figure 3 The tube 72 expands radially outward. In this case, since the outer peripheral surface 72b of the tube 72 fits into the first inner peripheral surface 211 of the outer connector tube 2, the expansion of the tube 72 can be limited by the outer connector tube 2. As a result, the formation of a gap between the inner connector tube 3 (cylindrical portion 32) and the tube 72 can be suppressed. Consequently, it is possible to prevent a portion of the sealing member 4 in the groove 344 from being squeezed into the aforementioned gap, or to prevent the radial crushing margin of the sealing member 4 from decreasing, thus effectively suppressing the decline in the sealing performance of the sealing member 4.

[0081] The pipe fitting structure 1 also has a first limiting part 5. Figure 7 This is a cross-sectional perspective view showing the first limiting part 5. Figure 3 and Figure 7 In the first limiting part 5, there is a pair of engaging protrusions 51 and a pair of engaging grooves 52. The pair of engaging protrusions 51 are integrally formed with the first inner peripheral surface 211 of the outer connector tube 2. The pair of engaging grooves 52 are provided on the outer peripheral surface 72b of the end of the tube 72. Figure 3 In the state shown, a pair of engagement grooves 52 are located on the opposite side of the axial direction, further than the sealing component 4.

[0082] A pair of engaging protrusions 51 are provided at equal intervals (180° intervals) along the circumferential direction of the first inner peripheral surface 211. Each engaging protrusion 51 is located between a pair of flexible tabs 24 in the circumferential direction. In this embodiment, each engaging protrusion 51 is located at the middle position between a pair of flexible tabs 24. Each engaging protrusion 51 protrudes radially inward from the first inner peripheral surface 211. Each engaging protrusion 51 is formed as a triangle, for example, when viewed in cross-section. Each engaging protrusion 51 has a tapered surface 51a and an engaging surface 51b.

[0083] The tapered surface 51a is inclined such that its protrusion length gradually increases from one axial end toward the other axial end toward the radially inner side of the engaging protrusion 51. The engaging surface 51b is a stepped surface formed between the other axial end of the tapered surface 51a and the first inner circumferential surface 211, and is formed perpendicular to the first inner circumferential surface 211.

[0084] A pair of engaging grooves 52 are formed at equal intervals (180° intervals) along the circumferential direction at the outer peripheral surface 72b of the end of the tube 72 (see also). Figure 9 The engaging protrusion 51 is embedded and engaged in each engaging groove 52. Therefore, the engaging groove 52 is formed to accommodate the entire engaging protrusion 51. In this embodiment, each engaging groove 52 is an elongated hole that extends circumferentially and is formed through the tube 72 along the thickness direction. The circumferential length of each engaging groove 52 is greater than the circumferential length of the engaging protrusion 51. The side surface on the other side of the axial direction of each engaging groove 52 is the engaging surface 52a that engages with the engaging surface 51b of the engaging protrusion 51.

[0085] With the outer peripheral surface 72b of the end of the tube 72 engaged with the first inner peripheral surface 211 of the outer connector tube 2, the engaging protrusion 51 is embedded in each engaging groove 52, and the engaging surface 51b of the engaging protrusion 51 is engaged with the engaging surface 52a of the engaging groove 52. This engagement restricts the relative axial movement of the tube 72 with respect to the first inner peripheral surface 211 of the outer connector tube 2. Therefore, by engaging the outer peripheral surface 72b of the end of the tube 72 with the first inner peripheral surface 211 of the outer connector tube 2, the first limiting part 5 can prevent the tube 72 from being pulled out axially with respect to the first inner peripheral surface 211 of the outer connector tube 2.

[0086] exist Figure 3 , Figure 5 and Figure 6 In the pipe fitting structure 1, a second limiting part 6 is also provided. The second limiting part 6 has a pair of hook parts 61 and a pair of hook grooves 62. The pair of hook parts 61 are integrally provided with the second inner peripheral surface 212 of the outer fitting pipe 2. The pair of hook grooves 62 are provided on the second outer peripheral surface 342 of the inner fitting pipe 3.

[0087] A pair of hook portions 61 are provided at equal intervals (180° intervals) along the circumference of the second inner peripheral surface 212. In this embodiment, each hook portion 61 is provided on the inner peripheral surface (second inner peripheral surface 212) on the side of the front end portion 24b of the flexible piece 24. By flexing and deforming the front end portion 24b of the flexible piece 24 radially, the hook portion 61 can be displaced radially relative to the outer connector tube 2.

[0088] The hook portion 61 is formed in the shape of a hook. The hook portion 61 has a first plate portion 61a that protrudes radially inward from the second inner peripheral surface portion 212 and a second plate portion 61b that extends axially to one side from the protruding end of the first plate portion 61a.

[0089] A pair of hook grooves 62 are formed at equal circumferential intervals (180° intervals) on the second outer peripheral surface 342 of the inner connector tube 3. Each hook groove 62 has a large groove portion 62a and a small groove portion 62b communicating with the large groove portion 62a. The large groove portion 62a is recessed from the second outer peripheral surface 342 toward the radially inner side of the inner connector tube 3. The large groove portion 62a is formed to a size for the hook portion 61 to be completely embedded. In this embodiment, the large groove portion 62a is, for example, a groove that is longer in the circumferential direction. The circumferential length of the large groove portion 62a is greater than the circumferential length of the hook portion 61. The axial length of the large groove portion 62a is greater than the axial length of the hook portion 61.

[0090] The small groove 62b is cut into the side of the large groove 62a from the bottom side towards the axial side. The small groove 62b is sized to allow the second plate portion 61b of the hook portion 61 to be inserted. The circumferential length of the small groove 62b is the same as the circumferential length of the large groove 62a. By inserting the second plate portion 61b of the hook portion 61 into the small groove 62b, the hook portion 61 is hooked into the hook groove 62.

[0091] like Figure 3 As shown, with the second outer peripheral surface 342 of the inner connector tube 3 fitted into the second inner peripheral surface 212 of the outer connector tube 2, each hook portion 61 of the second limiting portion 6 is inserted into the large groove portion 62a of the hook groove 62. If the inner connector tube 3 moves relative to the outer connector tube 2 from this state to the other side of the axial direction, the second plate portion 61b of the hook portion 61 hooks onto the small groove portion 62b.

[0092] This restricts the relative movement of the inner connector tube 3 to the other axial side relative to the second inner peripheral surface 212 of the outer connector tube 2. Therefore, by fitting the second outer peripheral surface 342 of the inner connector tube 3 into the second inner peripheral surface 212 of the outer connector tube 2, the second limiting part 6 can prevent the inner connector tube 3 from being pulled out to the other axial side relative to the second inner peripheral surface 212 of the outer connector tube 2.

[0093] Figure 8 This is a perspective view of the large groove 62a of the hook groove 62 of the second limiting part 6. Figure 3 and Figure 8 In the middle, conical surfaces 62c are formed on both sides of the circumference of each of the major grooves 62a (see also...). Figure 6 The conical surface 62c is inclined such that the depth of the groove gradually increases from the opening ends on both sides of the large groove 62a toward the bottom surface.

[0094] If from Figure 3From the indicated position, if the operator rotates the outer connector tube 2 relative to the inner connector tube 3 circumferentially to one side or the other, the second plate portion 61b of the hook portion 61 abuts against the conical surface 62c of the large groove portion 62a. If the operator rotates the outer connector tube 2 further from this position, the hook portion 61 moves radially outward relative to the outer connector tube 2 while moving along the conical surface 62c to the second outer peripheral surface 342. Thus, the hook portion 61 is pulled out of the hook groove 62. By moving the outer connector tube 2 relative to the inner connector tube 3 axially to the other side from this position, the outer connector tube 2 can be separated from the inner connector tube 3.

[0095] Construction methods for pipe fittings

[0096] Next, the construction method for connecting pipe 72 to the pipe joint structure 1 of this embodiment will be described. Figures 9 to 14 This is an explanatory diagram of the construction method. First, as... Figure 9 As shown, the operator inserts the end of the tube 72 from one axial side of the external connector tube 2 toward the inner circumferential side of the external connector tube 2. Thus, with respect to the end of the tube 72, a portion of its outer circumferential surface 72b engages with the first inner circumferential surface 211 of the external connector tube 2 while moving toward the other axial side.

[0097] Here, "relative insertion" of one tube into another means also includes any of the cases D, E, and F described below (as do the following).

[0098] D: The situation where one tube is inserted into another tube by moving the other tube while the first tube is stationary.

[0099] E: The situation where, with one tube stationary, another tube is inserted into another tube by moving the first tube.

[0100] F: The case where one tube is inserted into another tube by moving both tubes.

[0101] If the end of pipe 72 moves axially to the opposite side within the outer connector pipe 2, then as Figure 10 As shown by the solid line, the end face 72c of the tube 72 abuts against the tapered surface 51a of the engaging protrusion 51 on the side of the outer connector tube 2. If, from this state, the operator presses the tube 72 into the axial direction relative to the outer connector tube 2, the end of the tube 72 elastically deforms radially inward, thereby causing the end face 72c of the tube 72 to move relative to the axial direction along the tapered surface 51a, as... Figure 10 As shown by the double-dotted line, it crosses the engagement protrusion 51.

[0102] If, from this state, the operator further presses the pipe 72 inwards towards the opposite axial direction, then as... Figure 11 As shown, the engaging protrusion 51 is inserted into the engaging groove 52 of the first limiting part 5, and the outer peripheral surface 72b of the end of the tube 72 is integrally fitted with the first inner peripheral surface 211 of the outer connector tube 2. By engaging the engaging protrusion 51 into the engaging groove 52, the engaging surface 51b of the engaging protrusion 51 engages with the engaged surface 52a of the engaging groove 52.

[0103] Through this engagement, the first limiting part 5 restricts the tube 72 to move relative to the first inner peripheral surface 211 of the outer connector tube 2 in the axial direction. As a result, the first limiting part 5 can be pulled out axially relative to the first inner peripheral surface 211 of the outer connector tube 2.

[0104] Next, as Figure 12 As shown, the operator inserts the inner connector tube 3 into the inner circumferential side of the outer connector tube 2 from the opposite axial side. At this time, the operator inserts the inner connector tube 3 from the end on the axial side into the inner circumferential side of the outer connector tube 2. Thus, the first outer circumferential surface 341, the conical surface 343, and the second outer circumferential surface 342 of the inner connector tube 3 are sequentially inserted into the inner circumferential side of the outer connector tube 2.

[0105] The inner connector tube 3, which is inserted relative to the inner circumferential side of the outer connector tube 2, is further inserted relative to the inner circumferential side of the end of the tube 72, which is fitted with the first inner circumferential surface 211 of the outer connector tube 2. Thus, with regard to the inner connector tube 3, a portion of its first outer circumferential surface 341 fits with the inner circumferential surface 72a of the end of the tube 72 while moving relative to the other side axially. During this movement, the sealing member 4 on the inner connector tube 3 side comes into close contact with the inner circumferential surface 72a of the end of the tube 72 (see reference). Figure 13 Thus, the first outer peripheral surface 341 of the inner connector tube 3 and the inner peripheral surface 72a of the end of the tube 72 are sealed by the sealing member 4.

[0106] If the inner connector tube 3 moves further axially to the opposite side within the tube 72, then as Figure 13 As shown by the solid line, the hook portion 61 on the side of the outer connector tube 2 abuts against the tapered surface 343 of the inner connector tube 3. If, from this position, the operator presses the inner connector tube 3 into the outer connector tube 2 axially to one side, the hook portion 61, abutting against the tapered surface 343, presses the front end 24b of the flexible piece 24 of the outer connector tube 2 radially outward. Through this pressing force, the front end 24b of the flexible piece 24 flexes and deforms radially outward, thus the hook portion 61 shifts radially outward while moving relative to the tapered surface 343 from one axial side to the other. Therefore, as... Figure 13 As shown by the double-dotted line, the second plate portion 61b of the hook portion 61 rises to the second outer peripheral portion 342 of the inner connector tube 3.

[0107] If, from this state, the operator further presses the inner connector tube 3 into the axial direction, then as follows: Figure 14 As shown, the hook portion 61 is inserted into the hook groove 62 at the second limiting portion 6. Thus, the second outer peripheral surface 342 of the inner connector tube 3 is fully engaged with the second inner peripheral surface 212 of the outer connector tube 2, and the first outer peripheral surface 341 of the inner connector tube 3 is fully engaged with the inner peripheral surface 72a of the end of the tube 72.

[0108] By engaging the hook groove 62 with the hook portion 61, the second limiting portion 6 restricts the relative movement of the inner connector tube 3 to the other axial side relative to the second inner peripheral surface 212 of the outer connector tube 2, as described above. Thus, the second limiting portion 6 can prevent the inner connector tube 3 from being pulled out to the other axial side relative to the second inner peripheral surface 212 of the outer connector tube 2.

[0109] <Effects>

[0110] According to the pipe connector structure 1 of the first embodiment, by inserting the pipe 72 from one axial side toward the inner circumferential side of the outer connector pipe 2, the outer circumferential surface 72b of the pipe 72 is fitted with the first inner circumferential surface 211 of the outer connector pipe 2. Thus, the relative movement of the pipe 72 toward one axial side relative to the first inner circumferential surface 211 of the outer connector pipe 2 can be restricted by the first limiting part 5. In this state, by inserting the inner connector pipe 3 from the other axial side toward the inner circumferential side of the outer connector pipe 2, the first outer circumferential surface 341 of the inner connector pipe 3 is fitted with the inner circumferential surface 72a of the pipe 72, and the second outer circumferential surface 342 of the inner connector pipe 3 is fitted with the second inner circumferential surface 212 of the outer connector pipe 2. Thus, the first outer circumferential surface 341 of the inner connector pipe 3 and the inner circumferential surface 72a of the pipe 72 are sealed by the sealing member 4, and the relative movement of the inner connector pipe 3 toward the other axial side relative to the second inner circumferential surface 212 of the outer connector pipe 2 can be restricted by the second limiting part 6. Therefore, after the operator inserts the pipe 72 into the inner circumference of the outer connector pipe 2 from one axial side, the operator can easily connect the pipe 72 to the pipe connector structure 1 without using tools by simply inserting the inner connector pipe 3 into the inner circumference of the outer connector pipe 2 from the other axial side.

[0111] The first limiting part 5 is a structure in which the engaging protrusion 51 on the side of the outer connector tube 2 engages with the engaging groove 52 on the side of the tube 72, thus reliably limiting the relative movement of the tube 72 relative to the outer connector tube 2.

[0112] Compared to the sealing member 4 that seals the connection between the pipe 72 and the external connector pipe 2, the engagement groove 52 of the first limiting part 5 is located further axially to the other side. Therefore, leakage of the fluid being transported in the pipe 72 from the engagement groove 52 to the axial side of the external connector pipe 2 can be suppressed by the sealing member 4. As a result, there is no need to provide a separate sealing structure between the pipe 72 and the external connector pipe 2, thus simplifying the structure of the pipe connector structure 1.

[0113] The second limiting part 6 is a structure in which the hook part 61 on the side of the outer connector tube 2 hooks onto the hook groove 62 on the side of the inner connector tube 3. Therefore, the relative movement of the inner connector tube 3 relative to the outer connector tube 2 can be reliably limited. In addition, the hook part 61 is integrally provided with the outer connector tube 2, thereby simplifying the structure of the pipe connector structure 1.

[0114] Since the external connector pipe 2 does not come into contact with the corrosive fluid being transported, it can be made of a material that is cheaper than a corrosion-resistant material. This reduces the manufacturing cost of the pipe fitting structure 1.

[0115] [Second Implementation]

[0116] <Structure of pipe fittings>

[0117] Figure 15 This is a perspective view showing the pipe fitting structure 1 according to the second embodiment. Figure 16 This is a view of the outer connector pipe 2 of the pipe joint structure 1 as seen from the other side of the axial direction. In this embodiment, the structures of the outer connector pipe 2 and the second limiting part 6 differ from those in the first embodiment. Figure 15 and Figure 16 In this embodiment, the external connector tube 2 is a cylindrical component without a slit. A pair of through holes 25 are formed at the end on the other side of the axial direction of the external connector tube 2.

[0118] A pair of through holes 25 are formed at equal intervals (180° intervals) along the circumference of the outer connector tube 2. Each through hole 25 is an elongated hole that extends circumferentially through the outer connector tube 2 along the thickness direction. The radial inner end of each through hole 25 opens at the second inner circumferential surface 212 of the outer connector tube 2.

[0119] The second limiting part 6 includes a locking rod 63, a pair of guide rails 64, a pair of first limiters 65, and a pair of second limiters 66. The locking rod 63 is separately disposed from the outer connector tube 2. The locking rod 63 is, for example, a rod-shaped component made of the same synthetic resin material as the outer connector tube 2. In this embodiment, the locking rod 63 is formed, for example, in a generally U-shaped bend. The locking rod 63 has a pair of locking parts 631, an operating part 632, and a pair of guided parts 633.

[0120] A pair of locking portions 631 extend tangentially on both radial sides of the outer connector tube 2 and are arranged parallel to each other. In this embodiment, Figure 16 The vertical direction is the tangential direction of the outer connector tube 2 extending from the locking part 631. A portion 631a of the long side of each locking part 631 is inserted along the long side of each through hole 25 of the outer connector tube 2, and protrudes (exposes) radially inward more than the second inner peripheral surface 212 of the outer connector tube 2.

[0121] Hereinafter, in this invention, Figure 16 The vertical direction is simply referred to as the "tangent direction". For convenience, it will be... Figure 16 The upper side is called the "upper side of the tangent direction". Figure 16 The lower side is called the "tangential direction lower side". Additionally, Figure 16 The left and right directions are orthogonal to the "tangent direction," and are simply referred to as the "orthogonal direction." For convenience, the direction from the center point (axis O) of the external connector pipe 2 toward both sides of the orthogonal direction is called the "outer side of the orthogonal direction," and the direction from both sides of the orthogonal direction of the external connector pipe 2 toward the center point of the external connector pipe 2 is called the "inner side of the orthogonal direction." Figure 23 The same applies.

[0122] The operating part 632 of the locking rod 63 connects the upper tangential ends of a pair of locking parts 631 to each other. The operating part 632 is operated by the operator's fingers. The operating part 632 is disposed separately from the outer peripheral surface 22 of the outer connector tube 2 in the upper tangential direction. A pair of guided parts 633 of the locking rod 63 extend axially from the lower tangential end of each locking part 631. Each guided part 633 is disposed further outward in the orthogonal direction than the outer peripheral surface 22 of the outer connector tube 2.

[0123] A pair of guide rails 64 guide each of the guided portions 633 of the locking rod 63. Each guide rail 64 is fixed adjacent to each other on the outer peripheral surface 22 of the outer connector tube 2, below the tangential direction of each through hole 25. In this embodiment, each guide rail 64 is integrally provided with the outer peripheral surface 22 of the outer connector tube 2 and protrudes outward in an orthogonal direction from the outer peripheral surface 22. Each guide rail 64 has a guide surface 64a formed above its tangential direction.

[0124] The guide surface 64a is formed by a concave curved surface that slopes from the inside of the orthogonal direction and upward in the tangential direction toward the outside of the orthogonal direction and downward in the tangential direction. The guided portion 633 of the locking rod 63 abuts against the guide surface 64a of each guide rail 64. The guided portion 633 slides along the guide surface 64a.

[0125] A pair of first limiters 65 are fixed adjacent to each other on the outer peripheral surface 22 of the outer connector tube 2, tangentially above each guide rail 64. In this embodiment, each first limiter 65 is integrally formed with the outer peripheral surface 22 of the outer connector tube 2. Each first limiter 65 has a limiting surface 65a formed on its tangentially below side. The guided portion 633 of the locking rod 63 abuts against the limiting surface 65a. Figure 15 and Figure 16 In the state shown, each guided portion 633 of the locking bar 63 is located above the tangential direction of the guide surface 64a of each guide rail 64, and abuts against the limiting surface 65a of each first limiter 65.

[0126] A pair of second limiters 66 are fixed to the outer side of each guide rail 64 in the orthogonal direction. In this embodiment, each second limiter 66 is integrally provided with the guide rail 64. Each second limiter 66 protrudes to the upper side of the tangential direction and the outer side of the orthogonal direction, further than the guide surface 64a. Each second limiter 66 has a limiting surface 66a formed on the guide surface 64a side. If the guided portion 633 of the locking bar 63 slides along the guide surface 64a to the lower side in the tangential direction, it abuts against the limiting surface 66a of the second limiter 66.

[0127] Figure 17 It means from Figure 16 The diagram shows the state after the guided portion 633 of the locking bar 63 has slid along the guide surface 64a of the guide rail 64 to the lower side in the tangential direction, starting from the state shown. Figure 17 As shown, if a pair of guided portions 633 slide along the guide surfaces 64a of each guide rail 64 to the lower side in the tangential direction, the pair of locking portions 631 move away from each other in the orthogonal direction. Thus, for each locking portion 631, a portion 631a protrudes to a position that is radially inward from the second inner circumferential surface 212 of the outer connector tube 2. Figure 16 From this point onward, move to a position that is radially laterally more outward than the second inner peripheral face 212. Figure 17 Therefore, each locking portion 631 is configured to protrude radially inward relative to the outer connector tube 2 beyond the second inner peripheral surface 212, and to retract radially outward relative to the second inner peripheral surface 212.

[0128] Figure 18 This is a perspective view showing the inner connector tube 3 of the second embodiment. Figure 15 , Figure 16 and Figure 18 In the middle, the second limiting part 6 also has a pair of locking grooves 67 provided in the inner connector tube 3 (in Figure 18(Only one is shown in the figure). A pair of locking grooves 67 are provided on the second outer peripheral surface 342 of the inner connector tube 3. Specifically, a pair of locking grooves 67 are formed at equal intervals (180° intervals) along the circumferential direction on the second outer peripheral surface 342 of the inner connector tube 3. Each locking groove 67 is, for example, a groove that extends in the circumferential direction. In each locking groove 52, a portion 631a of each locking part 631 of the locking rod 63 is inserted and locked along its long side. Therefore, each locking groove 67 is formed to a size for the portion 631a of the locking part 631 to be inserted.

[0129] With the second outer peripheral surface 342 of the inner connector tube 3 engaged with the second inner peripheral surface 212 of the outer connector tube 2, a pair of locking portions 631 of the second limiting portion 6 are locked in the locking grooves 67 at the protruding positions (see reference). Figure 21 Therefore, the second limiting part 6 restricts the relative movement of the inner connector tube 3 to the other side of the axial direction relative to the second inner peripheral surface 212 of the outer connector tube 2.

[0130] With the relative movement of the inner connector tube 3 restricted by the second limiting part 6, the locking rod 63 is in a state where... Figure 16 The position shown. If, from this position, the operator presses the operating part 632 of the locking bar 63 downward in the tangential direction, then as shown... Figure 17 As shown, a pair of guided portions 633 slide along the guide surfaces 64a of each guide rail 64 to the lower side in the tangential direction. Through this sliding, a pair of locking portions 631 move away from each other in the orthogonal direction.

[0131] Therefore, each locking part 631 moves from the protruding position ( Figure 16 Towards the retreat position ( Figure 17 As the outer connector tube 2 moves relative to the inner connector tube 3, the locking parts 631 are released from their respective locking grooves 67. From this state, the operator can move the outer connector tube 2 axially to the other side relative to the inner connector tube 3, thereby enabling the outer connector tube 2 to be separated from the inner connector tube 3.

[0132] The other structures in this embodiment are the same as those in the first embodiment; therefore, the same reference numerals are used, and their descriptions are omitted.

[0133] Construction methods for pipe fittings

[0134] Next, the construction method for connecting pipe 72 to the pipe joint structure 1 of this embodiment will be described. Figures 19 to 21 This is an explanatory diagram of the construction method. First, compared with the first embodiment (refer to...) Figures 9 to 11Similarly, the operator inserts the end of tube 72 from the axial side of the outer connector tube 2 toward the inner circumferential side of the outer connector tube 2, so that the outer circumferential surface 72b of the end of tube 72 engages with the first inner circumferential surface 211 of the outer connector tube 2. At this time, the locking bar 63 of the second limiting part 6 remains in position. Figure 16 The state shown.

[0135] Next, as Figure 19 As shown, the operator inserts the inner connector tube 3 into the inner circumferential side of the outer connector tube 2 from the opposite axial side. This insertion operation is the same as in the first embodiment, therefore, detailed description is omitted. If the inner connector tube 3 is inserted into the inner circumferential side of the outer connector tube 2, then as... Figure 20 As shown by the solid line, the locking part 631 (part 631a) of the locking rod 63 abuts against the tapered surface 343 of the inner connector tube 3.

[0136] If, from this state, the operator presses the inner connector tube 3 relative to the outer connector tube 2 axially to one side, the locking part 631 moves relative to the outer connector tube 2 along the tapered surface 343 from one axial side to the other axial side, and from the inner side in the orthogonal direction to the outer side in the orthogonal direction. Thus, as... Figure 20 As shown by the double-dotted line, the locking part 631 is located at the protruding position ( Figure 16 Towards the retreat position ( Figure 17 The locking bar 63 moves and rises to the second outer peripheral surface 342 of the inner connector tube 3. At this time, each guided part 633 of the locking bar 63 slides along the guide surface 64a of each guide rail 64, thus enabling each locking part 631 to move smoothly.

[0137] If, from this state, the operator further presses the inner connector tube 3 into the axial direction, then as follows: Figure 21 As shown, the locking part 631 is embedded and locked in the locking groove 67 in the second limiting part 6. As a result, the second outer peripheral surface 342 of the inner connector tube 3 is fully engaged with the second inner peripheral surface 212 of the outer connector tube 2, and the first outer peripheral surface 341 of the inner connector tube 3 is fully engaged with the inner peripheral surface 72a of the end of the tube 72.

[0138] By engaging the locking part 631 with the locking groove 67, the second limiting part 6, as described above, restricts the relative movement of the inner connector tube 3 to the opposite axial direction of the second inner peripheral surface 212 of the outer connector tube 2. Thus, the second limiting part 6 can prevent the inner connector tube 3 from being pulled out to the opposite axial direction of the second inner peripheral surface 212 of the outer connector tube 2.

[0139] <Effects>

[0140] In the pipe connector structure 1 of the second embodiment, after the operator inserts the pipe 72 into the inner circumference of the outer connector pipe 2 from the axial side, the operator can easily connect the pipe 72 to the pipe connector structure 1 without using tools simply by inserting the inner connector pipe 3 into the inner circumference of the outer connector pipe 2 from the other axial side. Furthermore, the second limiting part 6 is a structure in which the locking part 631 on the outer connector pipe 2 side locks into the locking groove 67 on the inner connector pipe 3 side, thus reliably limiting the relative movement of the inner connector pipe 3 relative to the outer connector pipe 2.

[0141] [Third Implementation]

[0142] <Structure of pipe fittings>

[0143] Figure 22 This is a perspective view showing the pipe fitting structure 1 according to the third embodiment. Figure 23 This is a diagram showing the external connector pipe 2 of the pipe joint structure 1 viewed from the other side of the axial direction. Figure 24 From Figure 23 The diagram shows the external connector tube 2 viewed from the lower side. Furthermore, regarding... Figure 22 Regarding the inner connector tube 3, it is shown that it is larger than the annular portion 31 (see reference). Figure 6 More axially to one side ( Figure 27 Similarly), this embodiment is a variation of the second embodiment, and the structure of the second limiting part 6 differs from that of the second embodiment. Figures 22 to 24 In this embodiment, the second limiting part 6 has a locking bar 83.

[0144] Figure 25 This is a perspective view showing the locking bar 83. Figures 22 to 25 In this embodiment, the locking rod 83 is separately disposed on the outer connector tube 2. The locking rod 83 is, for example, a rod-shaped component made of the same synthetic resin material as the outer connector tube 2. The locking rod 83 of this embodiment has a pair of locking portions 831, a pair of guided portions 832, a pair of operating portions 833, a pair of first limiting portions 834 and a pair of second limiting portions 835.

[0145] A pair of locking portions 831 extend tangentially on both sides of the external connector tube 2 in the orthogonal direction and are arranged parallel to each other at a predetermined interval. In this embodiment, Figure 23 The vertical direction is the tangential direction of the outer connector tube 2 extending from the locking part 831. A portion 831a of the long side of each locking part 831 is inserted along the long side of each through hole 25 of the outer connector tube 2, and protrudes (exposes) radially inward more than the second inner peripheral surface 212 of the outer connector tube 2.

[0146] A pair of guided portions 832 extend from the tangentially upward end of each locking portion 831 toward the orthogonal inward direction and obliquely upward in the tangential direction. Most of each guided portion 832 is configured to be tangentially upward further than the outer peripheral surface 22 of the outer connector tube 2. A pair of operating portions 833 extend axially from the tangentially upward end of each guided portion 832 and are arranged parallel to each other in a close proximity. In this embodiment, the pair of operating portions 833 are positioned close to each other to the extent that they can be simultaneously pressed downward in the tangential direction by a single finger of the operator.

[0147] A pair of first limiting portions 834 extend axially from the lower end of each locking portion 831 in the tangential direction. A second limiting portion 835 connects the axial ends of a pair of operating portions 833 to each other. The second limiting portion 835 has a pair of extension portions 835a and a connecting portion 835b. Each extension portion 835a extends obliquely downward in the tangential direction from the lower end of each operating portion 833 towards the axial direction. The connecting portion 835b extends orthogonally to each other at the lower end of the tangential direction of the pair of extension portions 835a, connecting their ends to each other.

[0148] exist Figures 22 to 24 In the second limiting part 6, there is also a pair of guide rail grooves 84, a pair of first limiting grooves 85, and a second limiting groove 86 formed in the outer connector tube 2. The pair of guide rail grooves 84 are formed on the upper side of the tangential direction of each through hole 25 in the outer connector tube 2. Each guide rail groove 84 communicates with the corresponding through hole 25 and extends from the through hole 25 on the upper side of the tangential direction. Each guide rail groove 84 is a bottomed groove with an opening at the outer peripheral surface 22 of the outer connector tube 2.

[0149] On the bottom surface of each guide rail groove 84, a guide surface 84a is formed that slopes from the inner side of the orthogonal direction and the upper side of the tangential direction toward the outer side of the orthogonal direction and the lower side of the tangential direction. The upper end of the guide surface 84a in the tangential direction is connected to the outer peripheral surface 22 of the outer connector tube 2. The lower end of each guided part 832 of the locking bar 83 is abutted by the guide surface 84a of each guide rail groove 84. The aforementioned end of each guided part 832 slides obliquely along the corresponding guide surface 84a.

[0150] A pair of first limiting grooves 85 are formed on the lower side of the tangential direction of each through hole 25 of the external connector tube 2. Each first limiting groove 85 communicates with the corresponding through hole 25 and extends axially from the lower side of the tangential direction of the through hole 25. Each first limiting groove 85 is a bottomed groove with an opening at the outer peripheral surface 22 of the external connector tube 2. The bottom surface 85a of each first limiting groove 85 extends tangentially from the lower end of the tangential direction of the through hole 25 to the outer peripheral surface 22 of the external connector tube 2.

[0151] A limiting surface 85b is formed on the upper side of the tangential direction of each of the first limiting grooves 85. The limiting surface 85b extends in an orthogonal direction from the lower end of the tangential direction of the through hole 25 to the outer peripheral surface 22 of the outer connector tube 2. Figure 22 and Figure 23 In the shown state, the first limiting portion 834 of the locking bar 83 abuts against the bottom surface 85a and the limiting surface 85b of each first limiting groove 85. As a result, the locking bar 83 is restricted from moving upward in the tangential direction.

[0152] The second limiting groove 86 is formed on one axial side of the outer peripheral surface 22 of the outer connector tube 2. The second limiting groove 86 is formed at the middle position between a pair of guide rail grooves 84 and on the lower side of the tangential direction of the connecting portion 835b in the second limiting portion 835 of the locking bar 83. The second limiting groove 86 is a bottomed groove with an opening at the outer peripheral surface 22 of the outer connector tube 2. The bottom surface of the second limiting groove 86 is used as the limiting surface 86b. The limiting surface 86b extends to both sides in the orthogonal direction up to the outer peripheral surface 22 of the outer connector tube 2. If the second limiting portion 835 of the locking bar 63 moves downward in the tangential direction, the connecting portion 835b of the second limiting portion 835 abuts against the limiting surface 86b of the second limiting groove 86.

[0153] Figure 26 It means from Figure 23 The diagram shows the state after the locking bar 83 has moved downwards in the tangential direction, starting from the state shown. Figure 26 As shown, when the locking bar 83 moves downward in the tangential direction, the lower ends of the pair of guided portions 832 slide obliquely along the inclined guide surfaces 84a of each guide groove 84 toward the orthogonal direction outward and downward in the tangential direction. As a result, the pair of locking portions 831 move away from each other in the orthogonal direction outward.

[0154] As a result, regarding each locking portion 831, a portion 831a protrudes radially inward from the protruding position that is further inward than the second inner peripheral surface 212 of the outer connector tube 2. Figure 23 ) Move to a position that is further radially outward than the second inner peripheral face 212 ( Figure 26 Therefore, each locking portion 831 is configured to protrude radially inward relative to the outer connector tube 2 beyond the second inner peripheral surface 212, and to retract radially outward relative to the second inner peripheral surface 212. If each locking portion 831 moves from the protruding position to the retracted position, the second limiting portion 835 (connecting portion 835b) of the locking bar 83 abuts against the second limiting groove 86 (limiting surface 86b) of the outer connector tube 2, thereby restricting the locking bar 83 from moving downward in the tangential direction.

[0155] Figure 27 This is a cross-sectional perspective view showing the inner connector tube 3 of the third embodiment. Figure 22 , Figure 23 and Figure 27 In this embodiment, the second limiting part 6 also has a locking groove 87 provided in the inner connector tube 3. The locking groove 87 is provided on the second outer peripheral surface 342 of the inner connector tube 3. In this embodiment, the locking groove 87 is formed in a ring shape throughout the circumference of the second outer peripheral surface 342. In the locking groove 87, although not shown in the figure, a portion 831a of each locking part 831 of the locking rod 83 is embedded and locked. Therefore, the locking groove 87 is formed to a size for the portion 831a of the locking part 831 to be embedded. The locking groove 87 may also be formed in pairs at equal intervals along the circumference of the inner connector tube 3, similar to the second embodiment.

[0156] With the second outer peripheral surface 342 of the inner connector tube 3 engaged with the second inner peripheral surface 212 of the outer connector tube 2, a pair of locking portions 831 of the locking rod 83 are locked in the locking grooves 67 of the inner connector tube 3 at their protruding positions. Therefore, the second limiting portion 6 (locking rod 83 and locking grooves 87) restricts the relative movement of the inner connector tube 3 to the other side of the axial direction relative to the second inner peripheral surface 212 of the outer connector tube 2.

[0157] With the relative movement of the inner connector tube 3 restricted by the second limiting part 6, the locking rod 83 is in a state where... Figure 23 The position shown. With the movement restriction of the inner connector tube 3 released from this state, the operator simultaneously presses the pair of operating parts 833 of the locking bar 83 downwards in the tangential direction using a single finger (e.g., thumb). Thus, as... Figure 26 As shown, the lower tangential ends of a pair of guided portions 832 slide obliquely along the guide surfaces 84a of each guide groove 84 toward the orthogonal direction and downward in the tangential direction. Through this sliding, the pair of locking portions 831 move away from each other toward the orthogonal direction.

[0158] Therefore, each locking part 831 moves from the protruding position ( Figure 23 Towards the retreat position ( Figure 26 As the inner connector tube 3 moves, the pair of locking parts 831 are released from the locking between them and the locking grooves 87, thus releasing the movement restriction of the inner connector tube 3 implemented by the second limiting part 6. From this state, the operator can move the outer connector tube 2 relative to the inner connector tube 3 to the opposite side in the axial direction, thereby enabling the outer connector tube 2 to be separated from the inner connector tube 3.

[0159] The other structures in this embodiment are the same as in the second embodiment; therefore, the same reference numerals are used, and their descriptions are omitted. Furthermore, if the locking rod 63, locking portion 631, guided portion 633, guide rail 64, and locking groove 67 of the second embodiment are replaced with the locking rod 83, locking portion 831, guided portion 832, guide rail groove 84, and locking groove 87 of the third embodiment, the construction method of the pipe joint structure 1 in the third embodiment is the same as that in the second embodiment; therefore, its description is omitted.

[0160] <Effects>

[0161] In the pipe connector structure 1 of the third embodiment, after the operator inserts the pipe 72 into the inner circumference of the outer connector pipe 2 from the axial side, the operator can easily connect the pipe 72 to the pipe connector structure 1 without using tools simply by inserting the inner connector pipe 3 into the inner circumference of the outer connector pipe 2 from the other axial side. Furthermore, the second limiting part 6 is a structure in which the locking part 831 on the outer connector pipe 2 side locks into the locking groove 87 on the inner connector pipe 3 side, thus reliably limiting the relative movement of the inner connector pipe 3 relative to the outer connector pipe 2.

[0162] The locking bar 83 has a pair of operating parts 833 arranged in parallel when they are close to each other. Therefore, when releasing the movement restriction of the inner connector tube 3 implemented by the second restricting part 6, the operator can simultaneously press in both operating parts 833 with a single finger. As a result, compared with the second embodiment (see...), Figure 15 Compared to pressing in a single operating part 632, this reduces the burden on the operator's fingers.

[0163] The external connector tube 2 is formed with the same shape as in the second embodiment (see reference). Figure 16 The pair of guide rails 64 correspond to a pair of guide rail grooves 84. Therefore, compared with the case where a pair of guide rails 64 are provided on the outer peripheral surface 22 of the outer connector tube 2, the outer connector tube 2 can be manufactured more easily. In addition, the pipe connector structure 1 can be compactly formed in the orthogonal direction.

[0164] [Fourth Implementation]

[0165] <Structure of pipe fittings>

[0166] Figure 28 This is a perspective view showing the pipe fitting structure 1 according to the fourth embodiment. Figure 28 The inner connector tube 3 and the second limiting part 6 are omitted from the illustration. This embodiment is a variation of the third embodiment, and the structure of the outer connector tube 2 differs from that of the third embodiment. Figure 28 In this embodiment, the pipe fitting structure 1 is used when a pipe 72 made of a non-deformable material such as metal is connected to the flow path 71 of the fluid device 70 (see reference 71). Figure 3 ).

[0167] The pipe connector structure 1 has an external connector pipe 2 composed of a plurality of segments 26 divided circumferentially. In this embodiment, the external connector pipe 2 is divided into three segments circumferentially, and the plurality of segments 26 include a first segment 26A, a second segment 26B, and a third segment 26C. Hereinafter, the common aspects of the first segment 26A, the second segment 26B, and the third segment 26C will be described, and they will be collectively referred to as segments 26. Each segment 26 is formed in an arc shape. By combining the three segments 26 circumferentially, a cylindrical external connector pipe 2 is formed.

[0168] Figure 29 This is a perspective view showing the disassembled state of the external connector tube 2 in this embodiment. Figure 28 and Figure 29 In this embodiment, a first limiting portion 5 engaging protrusion 51 is integrally provided on one axial side of the inner circumferential surface of each segment 26. Therefore, in the first inner circumferential surface 211 of the outer connector tube 2, the first limiting portion 5 engaging protrusion 51 is provided at three circumferential locations. Although not shown in the figure, the engaging groove 52 of the first limiting portion 5 for engaging the engaging protrusion 51 (see reference) Figure 3 Also located on the outer circumferential surface 72b of the end of the pipe 72, at three circumferential locations.

[0169] A portion of a first limiting groove 35 is formed on the outer periphery of each of the first segment 26A and the third segment 26C. Other portions of each of the first limiting grooves 35 and a second limiting groove 86 are formed on the outer periphery of the second segment 26B. Hereinafter, for convenience, in this invention, for the purpose of convenience, [the following will be referred to as...]. Figure 29 The clockwise direction is called the "circumferential side". Figure 29 The counterclockwise direction is called "the other side of the circumference".

[0170] Each segment 26 has a first end face 261 on one circumferential side and a second end face 262 on the other circumferential side. The first end face 261 of one segment 26 of a circumferentially adjacent segment 26 abuts against the second end face 262 of the other segment 26.

[0171] The pipe fitting structure 1 of this embodiment also includes a fixing part 9 for fixing adjacent circumferentially spaced segments 26, 26 to each other. The number of fixing parts 9 in this embodiment is the same as the number of segments 26. Each fixing part 9 has a protrusion 91 provided on the first end face 261 of one of the adjacent circumferentially spaced segments 26, 26 and a recess 92 provided on the second end face 262 of the other segment 26.

[0172] A pair of protrusions 91 are provided at axial intervals at the first end face 261. Each protrusion 91 is formed, for example, in a cylindrical shape. Each protrusion 91 is integrally provided with the first end face 261 and protrudes from the first end face 261 toward one circumferential side (another segment 26).

[0173] A pair of recesses 92 are provided at axial intervals on the second end face 262. Each recess 92 is formed recessed to one side in the circumferential direction at a position on the second end face 262 opposite to each protrusion 91. Each recess 92 is, for example, formed as a circular hole, sized to allow the protrusion 91 to be completely inserted.

[0174] By inserting a pair of protrusions 91 of each fixing part 9 into their respective opposite recesses 92, the first end face 261 with the protrusions 91 abuts against the second end face 262 with the recesses 92. Thus, the circumferentially adjacent segments 26, 26 are fixed together by the fixing parts 9 through mutual assembly. Other structures in this embodiment are the same as in the third embodiment; therefore, the same reference numerals are used, and their descriptions are omitted.

[0175] The protruding portion 91 and the recessed portion 92 of each fixing part 9 may also be provided on the second end face 262 of the other dividing body 26 and the first end face 261 of the other dividing body 26, respectively. The shape and number of the protruding portion 91 and the recessed portion 92 of each fixing part 9 are not limited to this embodiment. For example, the number of protruding portions 91 and recessed portions 92 of each fixing part 9 may be 1, or may be greater than or equal to 3.

[0176] Construction methods for pipe fittings

[0177] Next, the construction method for connecting the piping 72 to the pipe fitting structure 1 of this embodiment will be described. Figure 30 This is an explanatory diagram of the construction method. First, as... Figure 30 As shown, the operator places one axial side of each of the three segments 26 on the radially outer side of the outer peripheral surface 72b of the end of the pipe 72, and then assembles these segments 26 circumferentially.

[0178] At this time, the protrusions 91 of each fixing part 9 are inserted into the corresponding recesses 92, so that the first end face 261 with the protrusions 91 abuts against the second end face 262 with the recesses 92. Thus, the protrusions 91 are inserted into the recesses 92, and therefore, the circumferentially adjacent segments 26, 26 are fixed by the fixing parts 9 in a mutually assembled state. In this way, by assembling the three segments 26 circumferentially, as... Figure 28 As shown, the outer peripheral surface 72b of the piping 72 is engaged with the first inner peripheral surface 211 of the external connector pipe 2 (also refer to...). Figure 3 ).

[0179] By engaging the piping 72 with the external connector pipe 2, the engaging protrusions 511 of each segment 26 of the external connector pipe 2 engage with the engaging grooves 52 provided on the outer peripheral surface 72b of the piping 72. As a result, the first limiting part 5 can prevent the piping 72 from being pulled out axially to one side relative to the first inner peripheral surface 211 of the external connector pipe 2.

[0180] Next, the operator inserts the inner connector tube 3 into the inner circumferential side of the outer connector tube 2 from the opposite axial side of the outer connector tube 2. This method is the same as in the third embodiment, therefore, its description is omitted.

[0181] <Effects>

[0182] According to the pipe connector structure 1 of the fourth embodiment, by arranging the axial side of a plurality of segmented parts 26 constituting the outer connector pipe 2 on the radially outer side of the outer peripheral surface 72b of the pipe 72, and circumferentially assembling these plurality of segmented parts 26, the outer peripheral surface 72b of the pipe 72 is fitted with the first inner peripheral surface 211 of the outer connector pipe 2. Thus, the relative movement of the pipe 72 relative to the first inner peripheral surface 211 of the outer connector pipe 2 to one axial side can be restricted by the first limiting part 5. In this state, by inserting the inner connector pipe 3 from the other axial side toward the inner peripheral side of the outer connector pipe 2, the first outer peripheral surface 341 of the inner connector pipe 3 is fitted with the inner peripheral surface 72a of the pipe 72, and the second outer peripheral surface 342 of the inner connector pipe 3 is fitted with the second inner peripheral surface 212 of the outer connector pipe 2. Thus, the first outer peripheral surface 341 of the inner connector tube 3 and the inner peripheral surface 72a of the pipe 72 are sealed by the sealing member 4, and the relative movement of the inner connector tube 3 relative to the second inner peripheral surface 212 of the outer connector tube 2 to the other side in the axial direction can be restricted by the second limiting part 6. Therefore, after the operator fits the outer peripheral surface 72b of the pipe 72 with the inner peripheral side of the outer connector tube 2, the pipe 72 can be easily connected to the pipe joint structure 1 without the use of tools simply by inserting the inner connector tube 3 relative to the inner peripheral side of the outer connector tube 2 from the other side in the axial direction.

[0183] Additionally, the pipe fitting structure 1 in the first embodiment (refer to...) Figure 3In the first limiting part 5, the engaging protrusion 51 protrudes radially inward from the inner circumference of the outer connector tube 2. Therefore, when inserting the tube (pipe) 72 from the axial side toward the inner circumference of the outer connector tube 2, it is necessary to deform the insertion end of the tube 72 while inserting it. Thus, it is impossible to connect the pipe 72, which is made of a material that is not easily deformable, such as metal, to the pipe connector structure 1. In contrast, in the pipe connector structure 1 of this embodiment, by assembling multiple segments 26 circumferentially on the radially outer side of the outer circumferential surface 72b of the pipe 72 as described above, the outer circumferential surface 72b of the pipe 72 can be fitted with the first inner circumferential surface 211 of the outer connector tube 2 without being obstructed by the engaging protrusion 51 of the first limiting part 5. Therefore, when fitting the outer circumferential surface 72b of the pipe 72 with the first inner circumferential surface 211 of the outer connector tube 2, it is not necessary to deform the pipe 72. Therefore, even a pipe 72 made of a material that is not easily deformable can be connected to the pipe connector structure 1.

[0184] The adjacent circumferential segments 26, 26 of the outer connector pipe 2 are fixed to each other by the fixing part 9, thereby preventing each segment 26 of the outer connector pipe 2 from falling off from the outer peripheral surface 72b of the pipe 72 and the second outer peripheral surface 342 of the inner connector pipe 3.

[0185] The fixing part 9 is a structure in which the protrusion 91 is inserted into the recess 92, so that the adjacent circumferentially adjacent segments 26, 26 can be reliably fixed to each other.

[0186] [Fifth Implementation]

[0187] <Structure of pipe fittings>

[0188] Figure 31 This is a perspective view showing the pipe fitting structure 1 according to the fifth embodiment. Figure 31 The inner connector tube 3 and the second limiting part 6 are omitted from the illustration. This embodiment is a variation of the fourth embodiment, and the structure of the fixing part 9 differs from that of the fourth embodiment. Figure 31 In this embodiment, the fixing part 9 of the pipe joint structure 1 has a pair of annular parts 93 provided at both ends of the outer joint pipe 2 along the axial direction.

[0189] A pair of annular components 93 includes a first annular component 93A and a second annular component 93B. With the three segments 26 assembled circumferentially, the first annular component 93A is mounted on one axial end of the external connector tube 2, and the second annular component 93B is mounted on the other axial end of the external connector tube 2. Hereinafter, when describing the commonalities of the first annular component 93A and the second annular component 93B, they will be collectively referred to as annular components 93.

[0190] Figure 32This is a perspective view showing the disassembled state of the external connector tube 2 and the fixing part 9 of this embodiment. Figure 31 and Figure 32 In the fixing part 9, each annular component 93 has a cylindrical portion 931 and an annular portion 932. The inner diameter of the cylindrical portion 931 is slightly larger than the outer diameter of each segment 26 (outer connector tube 2). The inner circumferential surface of the cylindrical portion 931 fits into the axial end of the outer circumferential surface 22 of the outer connector tube 2. This restricts the radial outward movement of each segment 26 in the outer connector tube 2.

[0191] In the first annular member 93A, the annular portion 932 is integrally formed with one axial side of the cylindrical portion 931. In the second annular member 93B, the annular portion 932 is integrally formed with the other axial side of the cylindrical portion 931. The inner diameter of the annular portion 932 of each annular member 93 is smaller than the outer diameter of each segment 26, and larger than the outer diameter of the pipe 72.

[0192] The annular portion 932 of the first annular member 93A has an end face 933 opposite to one end face 263 on the axial side of each segment 26. If the inner circumferential surface of the cylindrical portion 931 of the first annular member 93A is fitted with the outer circumferential surface 22 of the outer connector tube 2, then the end face 933 of the first annular member 93A abuts against one end face 263 of each segment 26. This restricts the movement of each segment 26 to one axial side.

[0193] The annular portion 932 of the second annular member 93B has an end face 934 that faces the other end face 264 on the other side of the axial direction of each segment 26. If the inner circumferential surface of the cylindrical portion 931 of the second annular member 93B is fitted with the outer circumferential surface 22 of the outer connector tube 2, then the end face 934 of the second annular member 93B abuts against the other end face 264 of each segment 26. This restricts the movement of each segment 26 to the other side of the axial direction.

[0194] Thus, by installing annular components 93 at the ends of the outer connector tube 2 on both sides of the axial direction with the three segments 26 assembled in the circumferential direction, the circumferentially adjacent segments 26 are fixed to each other.

[0195] Construction methods for pipe fittings

[0196] Next, the construction method for connecting the piping 72 to the pipe fitting structure 1 of this embodiment will be described. Figure 33 This is an explanatory diagram of the construction method. First, as... Figure 33 As shown, the operator inserts the first annular component 93A into the inner side of the axial side on the radially outer side of the outer peripheral surface 72b of the end of the pipe 72.

[0197] Next, the operator positions one axial side of each of the three segment 26 on the radially outer side of the outer peripheral surface 72b of the end of the pipe 72, further axially than the first annular component 93A, and assembles these segment 26 circumferentially. Specifically, the first end face 261 of one of the circumferentially adjacent segment 26 abuts against the second end face 262 of another segment 26 (see reference). Figure 28 ).

[0198] Next, the operator installs the first annular component 93A onto one axial end of the external connector tube 2, and installs the second annular component 93B onto the other axial end of the external connector tube 2 (see reference). Figure 31 At this time, the inner circumferential surface of the cylindrical portion 931 of each annular component 93 engages with the axial end of the outer circumferential surface 22 of the outer connector tube 2, thereby restricting the radial outward movement of each segment 26. Furthermore, the end faces 933 and 934 of each annular component 93 (see reference...) Figure 32 The connector abuts against one end face 263 and the other end face 264 of each segment 26, thereby restricting the movement of each segment 26 to both sides in the axial direction. Thus, the circumferentially adjacent segments 26 in the external connector pipe 2 are fixed to each other.

[0199] Next, the operator inserts the inner connector tube 3 into the inner circumferential side of the outer connector tube 2 from the opposite axial side of the outer connector tube 2. This method is the same as in the third embodiment, therefore, its description is omitted.

[0200] <Effects>

[0201] In the pipe fitting structure 1 of the fifth embodiment, after the operator fits the outer peripheral surface 72b of the pipe 72 with the inner peripheral side of the outer connector pipe 2, the pipe 72 can be easily connected to the pipe fitting structure 1 without tools simply by inserting the inner connector pipe 3 into the inner peripheral side of the outer connector pipe 2 from the other axial side. Furthermore, by assembling multiple segments 26 circumferentially on the radially outer side of the outer peripheral surface 72b of the pipe 72 as described above, the outer peripheral surface 72b of the pipe 72 can be fitted with the first inner peripheral surface 211 of the outer connector pipe 2 without being obstructed by the engaging protrusion 51 of the first limiting portion 5. Therefore, when fitting the outer peripheral surface 72b of the pipe 72 with the first inner peripheral surface 211 of the outer connector pipe 2, it is not necessary to deform the pipe 72; thus, even a pipe 72 made of a non-deformable material can be connected to the pipe fitting structure 1.

[0202] The adjacent circumferential segments 26, 26 of the outer connector pipe 2 are fixed to each other by the fixing part 9, thereby preventing each segment 26 of the outer connector pipe 2 from falling off from the outer peripheral surface 72b of the pipe 72 and the second outer peripheral surface 342 of the inner connector pipe 3.

[0203] The fixing part 9 is a structure in which a pair of annular parts 93 are installed at the ends of the outer connector tube 2 on both sides of the axial direction, so that the adjacent circumferentially adjacent split bodies 26, 26 can be reliably fixed to each other.

[0204] [other]

[0205] The embodiments disclosed above are illustrative in all respects and are not limiting. For example, the pipe fitting structure 1 of the present invention can be applied not only to hydrogen carrier manufacturing apparatuses, but also to semiconductor manufacturing apparatuses, liquid crystal or organic EL fields, medical or pharmaceutical fields, automotive-related fields, etc. Furthermore, the sealing component 4 can be a gasket other than an O-ring.

[0206] The first limiting part 5 is not limited to the above-described embodiment. For example, the engaging groove 52 may also be a groove that does not allow the pipe (pipe) 72 to pass through in the thickness direction. In addition, the engaging groove 52 may be located on the axial side further than the sealing member 4. In this case, it is sufficient to provide a separate sealing structure between the pipe (pipe) 72 and the external connector pipe 2 on the axial side further than the engaging groove 52.

[0207] The first limiting part 5 may have one or more than three engaging protrusions 51 and engaging grooves 52 in the circumferential direction. Alternatively, the engaging protrusion 51 may be separate from the outer connector tube 2. Alternatively, the engaging protrusion 51 may be provided on the outer circumferential surface 72b of the end of the tube 72, and the engaging groove 52 may be provided on the first inner circumferential surface 211 of the outer connector tube 2.

[0208] For example, it can also be like Figure 34 As shown, by making a portion of the axial direction of the pipe 72 (pipeline) protrude radially outward at its end, an annular engaging protrusion 51 is integrally formed, and an annular engaging groove 52 for engaging the engaging protrusion 51 is provided on the first inner circumferential surface 211 of the outer connector pipe 2. Furthermore, Figure 34 The engaging groove 52 is formed to be located on the opposite side of the axial direction, which is further away from the sealing member 4, but it can also be as follows: Figure 35 As shown, it is positioned on the axial side further than the sealing component 4. Figure 34 and Figure 35 The first limiting part 5 shown is as in the first embodiment (see reference). Figure 7 As shown, this is effective when it is difficult to machine the locking groove 52 in the pipe (pipeline) 72.

[0209] The second limiting part 6 is not limited to the above-described embodiment. For example, one or more or more hook parts 61 and hook grooves 62 may be provided in the circumferential direction. In addition, the hook part 61 may be separate from the outer connector tube 2. Alternatively, the hook part 61 may be provided on the second outer peripheral surface 342 of the inner connector tube 3, and the hook groove 62 may be provided on the second inner peripheral surface 212 of the outer connector tube 2.

[0210] The pipe joint structure 1 in the fourth and fifth embodiments has a fixing part 9 that fixes the circumferentially adjacent segments 26, 26 of the outer joint pipe 2 to each other. However, the fixing part 9 can be replaced by adhesive or the like to bond the circumferentially adjacent segments 26, 26 to each other.

[0211] In embodiments 4 and 5, the external connector tube 2 may also be composed of a segment 26 that is divided into two parts or into four or more parts along the circumferential direction.

[0212] In the fourth and fifth embodiments, the pipe fitting structure 1 connects to a pipe 72 made of a material that is not easily deformable. However, similar to the first embodiment, a pipe 72 made of easily deformable materials such as synthetic resin can also be connected. In this case, when the outer peripheral surface 72b of the pipe 72 is fitted with the first inner peripheral surface 211 of the outer connector pipe 2, the multiple segments 26 of the outer connector pipe 2 can be assembled circumferentially on the radially outer side of the outer peripheral surface 72b of the pipe 72. Alternatively, after assembling the multiple segments 26 circumferentially and fixing adjacent segments 26, 26 to each other by the fixing part 9, the pipe 72 can be inserted from the axial side of the outer connector pipe 2 while deforming the end of the pipe 72.

[0213] Explanation of the label

[0214] 1. Pipe Fitting Structure

[0215] 2 External connector pipe

[0216] 3. Internal connector tube

[0217] 4. Sealing components

[0218] 5. Section 1 (Restriction)

[0219] 6. Section 2 Restriction

[0220] 9. Fixing part

[0221] 26 Segments

[0222] 51 Engaging protrusion

[0223] 52-card slot

[0224] 61 Hook and Hanging Part

[0225] 62 Hook and Hanging Groove

[0226] 67. Locking groove

[0227] 70 Fluid devices (fluid equipment)

[0228] 71 flow path

[0229] 72 Pipe (pipeline)

[0230] 72a Inner circumferential surface

[0231] 72b outer periphery

[0232] 87 Locking Groove

[0233] 91 Protrusion

[0234] 92 concave part

[0235] 211 First inner peripheral face

[0236] 212 Second inner peripheral face

[0237] 341 Peripheral face of the first stage

[0238] 342 Second peripheral face

[0239] 631 Locking Part

[0240] 831 Locking Part

Claims

1. A pipe fitting structure for connecting piping to a flow path formed in a fluid device. The pipe fitting has the following features: An external connector pipe has a first inner circumferential surface on one axial side and a second inner circumferential surface on the other axial side, and the outer circumferential surface of the pipe is fitted from the axial side to the first inner circumferential surface. An inner connector tube has a first outer peripheral surface that engages with the inner circumferential surface of the piping from the other axial side on one side, and a second outer peripheral surface that engages with the second inner peripheral surface of the outer connector tube from the other axial side on the other side, the end of the other axial side being connected to the fluid device. A circular sealing component is disposed on the first outer peripheral surface of the inner connector pipe to seal between the first outer peripheral surface and the inner peripheral surface of the pipe. A first limiting portion, which engages with the first inner peripheral surface of the external connector pipe via its outer peripheral surface, thereby limiting relative movement of the pipe toward the axial side relative to the first inner peripheral surface; and The second limiting part, by engaging the second outer peripheral surface of the inner connector tube with the second inner peripheral surface of the outer connector tube, restricts the relative movement of the inner connector tube relative to the second inner peripheral surface towards the other side of the axial direction.

2. A pipe fitting structure for connecting piping to a flow path formed in a fluid device. The pipe fitting has the following features: An external connector pipe has a first inner circumferential surface on one axial side and a second inner circumferential surface on the other axial side, the outer circumferential surface of the pipe fitting into the first inner circumferential surface; An inner connector tube has a first outer peripheral surface that engages with the inner circumferential surface of the piping from the other axial side on one side, and a second outer peripheral surface that engages with the second inner peripheral surface of the outer connector tube from the other axial side on the other side, the end of the other axial side being connected to the fluid device. A circular sealing component is disposed on the first outer peripheral surface of the inner connector pipe to seal between the first outer peripheral surface and the inner peripheral surface of the pipe. A first limiting portion, which engages with the first inner peripheral surface of the external connector pipe via its outer peripheral surface, thereby limiting relative movement of the pipe toward the axial side relative to the first inner peripheral surface; and The second limiting part, by engaging the second outer peripheral surface of the inner connector tube with the second inner peripheral surface of the outer connector tube, restricts the relative movement of the inner connector tube relative to the second inner peripheral surface towards the other side of the axial direction. The external connector tube is composed of multiple segments cut along the circumference.

3. The pipe fitting structure according to claim 1 or 2, wherein, The first limiting portion has an engaging protrusion provided on one of the first inner peripheral surface of the external connector pipe and the outer peripheral surface of the piping, and an engaging groove provided on the other. The relative movement of the piping is restricted by the engagement protrusion engaging with the engagement groove.

4. The pipe fitting structure according to claim 3, wherein, The engagement groove is located on the opposite side of the axial direction, further away from the sealing component.

5. The pipe fitting structure according to claim 1 or 2, wherein, The second limiting part has a hook portion integrally provided on one of the second inner peripheral surface of the outer connector tube and the second outer peripheral surface of the inner connector tube, and a hook groove provided on the other. The relative movement of the inner connector tube is restricted by the hook portion hooking onto the hook groove.

6. The pipe fitting construction according to claim 1 or 2, wherein, The second limiting portion includes: a locking portion, which is separately disposed from the outer connector tube and is capable of protruding radially inward beyond the second inner peripheral surface; and a locking groove, which is disposed on the second outer peripheral surface of the inner connector tube. The locking portion protrudes radially inward and engages with the locking groove, thereby restricting the relative movement of the inner connector tube.

7. A method for constructing a pipe fitting structure, comprising a method for connecting the pipe in the pipe fitting structure of claim 1 for connecting piping to a flow path formed in a fluid device. The construction method for this pipe joint includes the following steps in sequence: The piping is inserted from one axial side of the external connector tube toward the inner circumferential side of the external connector tube, such that the outer circumferential surface of the piping is engaged with the first inner circumferential surface of the external connector tube; and The inner connector is inserted into the inner circumferential side of the outer connector from the opposite axial side of the outer connector, so that the first outer circumferential surface of the inner connector is fitted with the inner circumferential surface of the pipe, and the second outer circumferential surface of the inner connector is fitted with the second inner circumferential surface of the outer connector.

8. The pipe fitting structure according to claim 2, wherein, It also has a fixing part that fixes the circumferentially adjacent segments to each other.

9. The pipe fitting structure according to claim 8, wherein, The fixing part has a protrusion that protrudes from one of the adjacent segments toward the other segment along the circumferential direction and a recess provided in the other segment. The protrusions are embedded in the recesses, thereby fixing the circumferentially adjacent segments to each other.

10. A construction method for a pipe joint structure, comprising: It is a construction method for connecting the piping in the pipe fitting structure of claim 2, used for connecting piping to a flow path formed in a fluid device. The construction method for this pipe joint includes the following steps in sequence: By circumferentially assembling the plurality of segments, each with its axial side positioned radially outside the outer peripheral surface of the conduit, the outer peripheral surface of the conduit is fitted with the first inner peripheral surface of the external connector pipe; and The inner connector is inserted into the inner circumferential side of the outer connector from the opposite axial side of the outer connector, so that the first outer circumferential surface of the inner connector is fitted with the inner circumferential surface of the pipe, and the second outer circumferential surface of the inner connector is fitted with the second inner circumferential surface of the outer connector.

Images