Pipe joint

Abstract

To provide a pipe joint capable of temporarily fixing a pipe.SOLUTION: A pipe joint 30 includes a nut 32 having a through hole 34, and packing 36 attached to the nut 32 and arranged between a pipe 10 inserted into the through hole 34 and the nut 32. The packing 36 has a locking portion 60 abutted to an outer peripheral surface of the pipe 10. The nut 32 has a pressing portion 40 which presses the locking portion 60 toward the outer peripheral surface of the piping 10 inserted into the through hole 34 when the locking portion 60 is inserted into the through hole 34.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a pipe joint. [Background technology]

[0002] One type of pipe joint has been proposed in which a pipe is passed through a through hole in a cap nut and then the cap nut is fitted to the joint body (see, for example, Patent Document 1). The pipe joint of Patent Document 1 secures the pipe by using the joint body to press a stop ring arranged in the through hole, causing claws formed at the tip of the stop ring to bite into the outer peripheral surface of the pipe. Here, if the cap nut and the pipe are made of different metals, there is a risk of contact corrosion between the dissimilar metals, so an annular insulating packing is attached to the cap nut. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-270846 Summary of the Invention [Problem to be solved by the invention]

[0004] The pipe is not fixed in place from the time the pipe is passed through the through hole in the cap nut until the cap nut and fitting body are completely fastened together. As a result, the pipe can come loose from the cap nut or become misaligned during connection work, such as when fitting the cap nut to the fitting body or when screwing the cap nut onto the fitting body.

[0005] The present disclosure has been proposed in view of the above-mentioned problems associated with the conventional technology, and aims to provide a pipe fitting that can temporarily fix piping. [Means for solving the problem]

[0006] A first aspect of the pipe fitting according to the present disclosure includes: A pipe joint comprising a nut having a through hole, and a packing disposed between a pipe inserted into the through hole and the nut, The packing has a locking portion that abuts against an outer peripheral surface of the pipe, The nut has a pressing portion that presses the locking portion toward the outer peripheral surface of the pipe inserted into the through hole as the locking portion is inserted into the through hole. According to the pipe joint of the present disclosure, the piping can be temporarily fixed by the packing.

[0007] A second aspect of the pipe fitting according to the present disclosure is the same as the first aspect, The pressing portion may protrude toward the axial center of the through hole on a deeper side than an entrance side of the through hole through which the locking portion is inserted.

[0008] A third aspect of the pipe fitting according to the present disclosure is the pipe fitting according to the second aspect, The pressing portion may have an inclined surface that inclines toward the axial center of the through hole as it goes from the entrance side to the back side of the through hole.

[0009] A fourth aspect of the pipe fitting according to the present disclosure is any one of the first aspect, the second aspect, and the third aspect, the packing has an attachment operation portion that is disposed outside the through hole when the locking portion is inserted into the through hole, the mounting operation portion has an insertion hole into which the piping is inserted, The locking portion may be inclined toward the axial center of the insertion hole from the mounting operation portion toward the tip of the locking portion.

[0010] A fifth aspect of the pipe fitting according to the present disclosure is any one of the first aspect, the second aspect, the third aspect, and the fourth aspect, The nut has a threaded first mounting portion, The packing may have a threaded first mounting portion that engages with the first mounted portion.

[0011] A sixth aspect of the pipe fitting according to the present disclosure is any one of the first aspect, the second aspect, and the third aspect, The device may further include a pressing member attached to the nut for pressing the packing toward the back of the through hole.

[0012] A seventh aspect of the pipe fitting according to the present disclosure is the pipe fitting according to the sixth aspect, The nut has a second threaded mounting portion, The pressing member may have a second mounting portion in the form of a screw that engages with the second mounting portion. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a vertical cross-sectional view showing a pipe joint according to a first embodiment. [Figure 2] 1 is an exploded vertical cross-sectional view of a pipe joint according to a first embodiment. [Figure 3] FIG. 2 is a side view showing the pipe joint of the first embodiment. [Figure 4] FIG. 2 is an exploded side view of the pipe joint of the first embodiment. [Figure 5] FIG. 2 is a perspective view showing the packing of the first embodiment. [Figure 6] FIG. 2 is a front view showing the packing of the first embodiment. [Figure 7] FIG. 2 is a front view showing the nut of the first embodiment. [Figure 8] FIG. 2 is a front view showing the stop ring of the first embodiment. [Figure 9A] 5A to 5C are explanatory views showing a procedure for connecting the pipe joint of the first embodiment. [Figure 9B] 5A to 5C are explanatory views showing a procedure for connecting the pipe joint of the first embodiment. [Figure 9C] 5A to 5C are explanatory views showing a procedure for connecting the pipe joint of the first embodiment. [Figure 9D] 5A to 5C are explanatory views showing a procedure for connecting the pipe joint of the first embodiment. [Figure 10] FIG. 10 is a vertical cross-sectional view showing a pipe joint according to a second embodiment. [Figure 11]FIG. 6 is an exploded vertical cross-sectional view showing a pipe joint according to a second embodiment. [Figure 12] FIG. 6 is a side view showing a pipe joint according to a second embodiment. [Figure 13] FIG. 6 is an exploded side view showing a pipe joint according to a second embodiment. [Figure 14] FIG. 10 is a front view showing a nut according to a second embodiment. [Figure 15] FIG. 10 is a front view showing a packing according to a second embodiment. [Figure 16] FIG. 10 is a front view showing a pressing member of a second embodiment. [Figure 17A] 10A to 10C are explanatory views showing a procedure for connecting a pipe joint according to a second embodiment. [Figure 17B] 10A to 10C are explanatory views showing a procedure for connecting a pipe joint according to a second embodiment. [Figure 17C] 10A to 10C are explanatory views showing a procedure for connecting a pipe joint according to a second embodiment. [Figure 17D] 10A to 10C are explanatory views showing a procedure for connecting a pipe joint according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Next, a pipe fitting according to the present disclosure will be described below by way of preferred embodiments with reference to the accompanying drawings. Note that the embodiments and drawings described below exemplify a portion of the embodiments and are not intended to limit the scope of the present disclosure, and may be modified as appropriate without departing from the spirit and scope of the present disclosure.

[0015] (First embodiment) As shown in FIGS. 1 to 4, a pipe fitting 30 according to a first embodiment is used to connect a connection portion 12 provided in equipment such as an air conditioner to a pipe 10. The pipe fitting 30 includes a nut 32 having a through hole 34 through which the pipe 10 can be inserted, and a gasket 36 attached to the nut 32 and disposed between the nut 32 and the pipe 10 inserted into the through hole 34. The pipe fitting 30 also includes a stop ring 38 disposed in the through hole 34 of the nut 32 (see FIGS. 1 and 2). The pipe fitting 30 secures the pipe 10 by attaching the nut 32, with the pipe 10 inserted into the through hole 34, to the connection portion 12 via the stop ring 38, which is pressed against the connection portion 12, thereby connecting the pipe 10 to the connection portion 12. The pipe fitting 30 according to the first embodiment is classified as a non-flare fitting, which is a type of so-called flare fitting that can be connected to the connection end of the pipe 10 as is (see FIGS. 2 and 4) without flaring the end into a trumpet shape. The pipe 10 that is the target of the pipe fitting 30 of the present disclosure may be a metal pipe such as aluminum, copper, or iron, or a plastic pipe, and may be made of the same material as or a different material from the nut 32. In the following description of the pipe fitting 30, the side to which the pipe 10 is attached is referred to as the insertion side, and the side to which the connecting portion 12 is attached is referred to as the connection side.

[0016] 1 and 2, the nut 32 has a through hole 34 that penetrates from the insertion side to the connection side. The nut 32 has a pressing portion 40 that presses a packing 36 (a locking portion 60 of the packing 36, which will be described later) inserted into the through hole 34 toward the outer peripheral surface of the piping 10 inserted into the through hole 34. The nut 32 also has a first mounting portion 42 that is provided on the insertion side of the through hole 34 and is used to mount the packing 36. The first mounting portion 42 in the first embodiment has a female thread shape. In the nut 32, the first mounting portion 42 is located near the entrance of the insertion side of the through hole 34, and the pressing portion 40 is located further back (on the connection side) than the first mounting portion 42 in the through hole 34.

[0017] As shown in FIGS. 1 and 2 , the retaining portion 40 protrudes toward the axial center of the through hole 34 on its rear side compared to the entrance side of the through hole 34 where the packing 36 (the locking portion 60 of the packing 36) is inserted. The inner diameter of the retaining portion 40 is narrower on its rear side than on its entrance side. More specifically, the retaining portion 40 has an inclined surface that slopes toward the axial center of the through hole 34 as it extends from the entrance side to the rear side of the through hole 34. The retaining portion 40 is formed around the entire circumferential direction of the through hole 34 (see FIG. 7 ). The retaining portion 40 is disposed on the insertion path of the locking portion 60 of the packing 36 inserted into the through hole 34. When the packing 36 is attached to the nut 32, the locking portion 60, which comes into contact with the retaining portion 40, is guided toward the axial center of the through hole 34 as the locking portion 60 is inserted into the through hole 34, and the retaining portion 40 presses the locking portion 60 radially inward of the through hole 34.

[0018] As shown in FIGS. 1 and 2 , the nut 32 has a female thread portion 44 provided on the connection side of the through hole 34. In the through hole 34 of the nut 32, a seal groove 46, a first linear portion 48, a stepped portion 50, a second linear portion 52, a tapered portion 54, and a third linear portion 56 are formed in this order from the female thread portion 44 toward the insertion side. The seal groove 46 is a portion in which a connection seal member 58 such as an O-ring is disposed, and is formed with a larger inner diameter than the adjacent female thread portion 44 and first linear portion 48. The connection seal member 58 is preferably made of rubber such as IIR (butyl rubber), EPDM (ethylene propylene diene rubber), or NBR (nitrile rubber). For piping for refrigerant in air conditioning equipment such as an air conditioner, EPDM is preferably used, as it has excellent lifespan characteristics. IIR, which has excellent durability against refrigerants, may also be used. The first linear portion 48 is formed with approximately the same inner diameter. The second straight portion 52 has a smaller inner diameter than the first straight portion 48. The stepped portion 50 is a step formed between the first straight portion 48 and the second straight portion 52. The tapered portion 54 protrudes toward the axial center of the through hole 34 on the insertion side compared to the connection side. The tapered portion 54 has a narrower inner diameter on the insertion side compared to the inner diameter on the connection side. More specifically, the tapered portion 54 is an inclined surface that slopes toward the axial center of the through hole 34 from the connection side toward the insertion side. The third straight portion 56 is provided between the tapered portion 54 and the retainer portion 40 and has an inner diameter slightly larger than the outer diameter of the piping 10 to be inserted into the through hole 34. In the nut 32, the first straight portion 48, the stepped portion 50, the second straight portion 52, and the tapered portion 54 of the through hole 34 form a storage portion for storing the stop ring 38.

[0019] The material of the nut 32 is not particularly limited, but metals such as brass (brass) such as C3604 can be used. Furthermore, it is preferable that the outer shape of the nut 32 be formed into a polygonal shape such as a hexagonal cross section, since this makes it easier to apply rotational torque while gripping the nut 32 with a tool such as a wrench or with the operator's hand.

[0020] As shown in FIGS. 5 and 6, the packing 36 is cylindrical and has an insertion hole 36a through which the pipe 10 is inserted. The packing 36 includes a locking portion 60 that contacts the outer peripheral surface of the pipe 10, a first mounting portion 62 that attaches to the first mounted portion 42 of the nut 32, and an attachment operation portion 64 that serves as an operation portion when attaching the packing 36 to the nut 32 (see FIGS. 1, 2, and 4 to 6). Examples of materials that can be used for the packing 36 include rubbers such as EPDM (ethylene propylene diene rubber) and NBR (nitrile rubber), and plastics such as polyethylene, cross-linked polyethylene, and polypropylene. Among these, EPDM is preferred as the material for the packing 36 because of its excellent durability and weather resistance. It is also desirable for the packing 36 to be an insulating packing.

[0021] As shown in FIG. 1, the locking portion 60 is inserted into the through-hole 34 of the nut 32 and is formed to surround the insertion hole 36a. The tip of the locking portion 60 protrudes toward the axial center of the insertion hole 36a from the base side connected to the first mounting portion 62 (see FIG. 2). In the first embodiment, the inner diameter of the area surrounded by the tip of the locking portion 60 is smaller than the outer diameter of the pipe 10. More specifically, the locking portion 60 inclines toward the axial center of the insertion hole 36a from the mounting operation portion 64 side toward the tip of the locking portion 60. The locking portion 60 also has a curved shape with a convex outer surface. Furthermore, the locking portion 60 is formed in an annular shape that can abut against the entire outer periphery of the pipe 10 (see FIGS. 5 and 6). The locking portion 60 of the first embodiment also functions as a seal to seal the entire outer surface of the piping 10 when the gasket 36 is attached to the nut 32, preventing water from entering inside the through hole 34 in the nut 32 (see Figure 1).

[0022] As shown in FIG. 1, the first mounting portion 62 is a portion that is inserted into the through-hole 34 of the nut 32. The first mounting portion 62 in the first embodiment has a male thread that meshes with the female thread of the first mounted portion 42 of the nut 32. The mounting operation portion 64 is a portion that is disposed outside the through-hole 34 when the locking portion 60 is inserted into the through-hole 34 (see FIG. 3), and has a larger outer diameter than the first mounting portion 62. The mounting operation portion 64 has a polygonal cross-sectional shape (see FIGS. 5 and 6), making it easy to operate the mounting operation portion 64 with a tool such as a wrench or with the operator's hand. In the first embodiment, the cross-sectional shape of the mounting operation portion 64 is octagonal, but it may have another polygonal shape, such as a hexagonal cross-sectional shape.

[0023] As shown in FIG. 1, the stop ring 38 is disposed in a receiving portion of the through hole 34 of the nut 32. The stop ring 38 is cylindrical (see FIG. 8). The stop ring 38 has a basic outer diameter portion 66 slidably disposed in the first linear portion 48 of the through hole 34 of the nut 32, and a small diameter portion 70 connected to the insertion side of the basic outer diameter portion 66 via a step portion 68. The inner circumferential surface of the stop ring 38 is formed with a seal groove 74 for disposing a pipe seal member 72 such as an O-ring. The material of the stop ring 38 is not particularly limited, but examples thereof include metals such as brass and plastics such as polyethylene, cross-linked polyethylene, and polypropylene. The pipe seal member 72 is preferably made of rubber such as IIR (butyl rubber), EPDM (ethylene propylene diene rubber), or NBR (nitrile rubber). For piping used in refrigerant-carrying air conditioning equipment, IIR is preferred, as it has excellent durability against refrigerants.

[0024] 1, the connection-side end of the stop ring 38 is formed with a sloped surface 76 that protrudes inward from the connection side toward the insertion side. Note that the sloped surface 76 in the first embodiment bulges in an arc shape toward the inside of the stop ring 38. The sloped surface 76 abuts against a tapered, reduced-diameter tip portion 86 of the connection portion 12 to seal the gap between the connection portion 12 and the stop ring 38. The stop ring 38 also has a step portion 78 formed between the sloped surface 76 and the inner circumferential surface, and the end face of the pipe 10 inserted inside the stop ring 38 can be positioned by abutting the step portion 78 against the end face of the pipe 10.

[0025] As shown in FIGS. 1 and 2, the stop ring 38 has a plastically deformable deformation portion 80 provided at its insertion end, and claw portions 82 formed at the tip of the deformation portion 80 and engaging with the outer peripheral surface of the pipe 10. The deformation portion 80 of the first embodiment is configured to be deformable radially inward by reducing the wall thickness of the insertion end of the stop ring 38. The deformation portion 80 is formed in an annular shape that surrounds the entire outer peripheral surface of the pipe 10 (see FIG. 8). The claw portions 82 are formed in a triangular cross section, and are shaped to easily engage with the outer peripheral surface of the pipe 10 against the pull-out force of the pipe 10. The claw portions 82 are also formed in an annular shape that can abut against the entire outer peripheral surface of the pipe 10 (see FIG. 8).

[0026] 1 and 2, the connecting part 12 has a male threaded part 84 that meshes with the female threaded part 44 of the nut 32, and a tip reduced diameter part 86 that is provided at the tip of the male threaded part 84 and becomes thinner towards the tip. The material of the connecting part 12 is not particularly limited, but examples that can be used include metals such as brass, and plastics such as polyethylene, cross-linked polyethylene, and polypropylene.

[0027] The connection of a pipe 10 using the pipe fitting 30 of the first embodiment will be described with reference to Figures 9A to 9D. The stop ring 38 and the connection seal member 58 are pre-assembled to the nut 32 before the connection of the pipe 10 (see Figure 9A). The packing 36 is attached to the nut 32 by engaging the first mounting portion 62 of the packing 36 with the first mounted portion 42 of the nut 32. At this time, the packing 36 is positioned on the nut 32 so that the locking portion 60 does not come into contact with the pressing portion 40 of the nut 32. The pipe 10 is passed through the insertion hole 36a of the packing 36 and inserted into the through hole 34 of the nut 32, and is inserted inside the stop ring 38 until it comes into contact with the stepped portion 78 of the stop ring 38 (see Figure 9B). At this time, the locking portion 60 of the packing 36 is disengaged from the holding portion 40 of the nut 32 and does not come into strong contact with the outer peripheral surface of the pipe 10, so the position of the pipe 10 can be easily changed with respect to the insertion hole 36a of the packing 36. Note that the order of inserting the pipe 10 from the insertion hole 36a of the packing 36 into the through hole 34 of the nut 32 with the packing 36 loosely attached to the nut 32 (a state in which the holding portion 40 is not pressing the locking portion 60 to a weak degree) is not limited to this. The packing 36 and the pipe 10 may be combined and then the packing 36 may be attached to the nut 32.

[0028] Next, by rotating the packing 36 relative to the nut 32, the threaded first mounting portion 62 of the packing 36 engages with the threaded first mounted portion 42 of the nut 32, causing the locking portion 60 to move toward the back of the through-hole 34 (see FIG. 9C). As the locking portion 60 is inserted into the through-hole 34, it comes into contact with the retaining portion 40 of the nut 32 and is guided toward the axial center of the through-hole 34, where it is firmly pressed against the outer peripheral surface of the pipe 10 from the outside by the retaining portion 40 (see FIG. 1). In this way, the pipe 10 is held by the locking portion 60 of the packing 36, and the pipe 10 is temporarily fixed in a positioned state relative to the nut 32. The packing 36 is preferably attached to the nut 32 using the attachment operation portion 64 of the packing 36.

[0029] Next, the nut 32, which temporarily secures the pipe 10, and the connection part 12 are attached (see FIG. 9D). The male threaded portion 84 of the connection part 12 and the female threaded portion 44 of the nut 32 are rotated relative to each other while they are engaged, causing the tip reduced diameter portion 86 of the connection part 12 to abut against the inclined surface 76 of the stop ring 38. As the male threaded portion 84 and the female threaded portion 44 engage with each other, the stop ring 38 is pushed toward the insertion side of the through hole 34. As the stop ring 38 is pushed toward the insertion side, the deformed portion 80 of the stop ring 38 abuts against the tapered portion 54 of the nut 32, and is guided toward the axial center of the through hole 34, causing the deformed portion 80 to be squeezed radially inward. As a result, the claws 82 formed at the tip of the deformed portion 80 bite into the outer peripheral surface of the pipe 10, securing the pipe 10 so that it does not come off the nut 32, and the pipe 10 and the connection part 12 are connected (see FIG. 1).

[0030] The gasket 36 of the pipe fitting 30 has a locking portion 60 that abuts against the outer peripheral surface of the pipe 10. The nut 32 of the pipe fitting 30 also has a retaining portion 40 that presses the locking portion 60 toward the outer peripheral surface of the pipe 10 inserted into the through hole 34 as the locking portion 60 is inserted into the through hole 34. By attaching the gasket 36 to the nut 32, the pipe fitting 30 can temporarily fix the pipe 10 to the nut 32 with the locking portion 60 pressed by the retaining portion 40, and can also position the two. Because the pipe 10 is temporarily fixed to the nut 32 in the pipe fitting 30, problems such as the pipe 10 coming loose from the nut 32 or the pipe 10 becoming misaligned when the nut 32 is attached to the connection portion 12 can be prevented. Therefore, the pipe fitting 30 of the present disclosure significantly improves the ease of connecting the pipe 10 to the connection portion 12. Furthermore, the pipe fitting 30 of the present disclosure can prevent connection failures caused by the pipe 10 being misaligned during the connection work.

[0031] The retaining portion 40 protrudes toward the axial center of the through hole 34 at its rear side compared to the entrance side of the through hole 34 where the locking portion 60 is inserted. As a result, by arranging the locking portion 60 of the packing 36 on the rear side of the through hole 34, the retaining portion 40 can press the locking portion 60 firmly against the outer peripheral surface of the piping 10. Conversely, by arranging the locking portion 60 of the packing 36 on the entrance side of the through hole 34, the pressing force of the locking portion 60 on the piping 10 by the locking portion 60 is released or reduced, so the position of the piping 10 can be easily adjusted. In this way, according to the pipe fitting 30 of the present disclosure, the pressing force applied to the locking portion 60 by the retaining portion 40 can be adjusted, thereby improving the workability of connecting the piping 10.

[0032] The retaining portion 40 has an inclined surface that inclines toward the axial center of the through hole 34 as it moves from the entrance side of the through hole 34 to the back side, which prevents the retaining portion 60 from getting caught on the retaining portion 40 when the retaining portion 60 is inserted into the through hole 34. Furthermore, as the retaining portion 60 is inserted into the through hole 34, the inclined surface of the retaining portion 40 can smoothly guide the retaining portion 60 toward the axial center of the through hole 34.

[0033] The packing 36 has an attachment operation portion 64 that is disposed outside the through hole 34 when the locking portion 60 is inserted into the through hole 34, and use of the attachment operation portion 64 improves the workability of attaching the packing 36 to the nut 32. The locking portion 60 is inclined toward the axial center of the insertion hole 36a as it moves from the attachment operation portion 64 toward the tip of the locking portion 60. Therefore, when the locking portion 60 abuts against the pressing portion 40, the inclined shape of the locking portion 60 itself also guides the locking portion 60 toward the axial center of the through hole 34 (insertion hole 36a). As a result, when the locking portion 60 abuts against the pressing portion 40 as it is inserted into the through hole 34, the locking portion 60 can be smoothly guided toward the axial center of the through hole 34. In particular, it is preferable that the outer surface of the locking portion 60 is a curved surface that convex outward, because when the locking portion 60 abuts against the pressing portion 40 as it is inserted into the through hole 34, the locking portion 60 can be guided more smoothly toward the axial center of the through hole 34.

[0034] The pipe fitting 30 described above is configured so that the nut 32 and the packing 36 are assembled by meshing the threaded first mounted portion 42 of the nut 32 with the threaded first mounting portion 62 of the packing 36. This type of threaded fitting structure between the nut 32 and the packing 36 allows the packing 36 to be easily mounted to the nut 32. It also seals the gap between the nut 32 and the packing 36 to prevent water from entering. Furthermore, the position of the locking portion 60 in the through hole 34 can be easily adjusted by changing the amount the packing 36 is screwed into the nut 32, and the mounting position of the packing 36 relative to the nut 32 can be maintained.

[0035] Because the locking portion 60 is formed in an annular shape that can contact the entire outer peripheral surface of the pipe 10, the locking portion 60 pressed by the pressing portion 40 can seal the gap between the packing 36 and the pipe 10 to prevent water from entering the nut 32. In this way, the packing 36 not only temporarily secures the pipe 10 but also functions as a seal to prevent water from entering. For example, in the case of a combination of dissimilar metals, such as the pipe 10 being an aluminum pipe and the nut 32 being brass, the sealing function of the packing 36 can prevent corrosion (galvanic corrosion) that occurs when water that has entered the through-hole 34 gets between the nut 32 and the pipe 10.

[0036] (Second embodiment) In the pipe fitting 30 according to the first embodiment, the packing 36 itself is provided with a structure that presses the locking portion 60 toward the pressing portion 40 of the nut 32 and maintains that state, but as in the pipe fitting 90 according to the second embodiment, a structure may also be provided that includes a pressing member 110 that presses the locking portion 102 of the packing 100 toward the pressing portion 40 of the nut 92 and maintains that state, separate from the packing 100. Note that the same components in the second embodiment as those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and descriptions thereof will be omitted.

[0037] 10 to 13, a pipe fitting 90 according to the second embodiment includes a nut 92 having a through hole 34 into which a pipe 10 can be inserted, a packing 100 attached to the nut 92 and disposed between the nut 92 and the pipe 10 inserted into the through hole 34, and a pressing member 110 attached to the nut 92 and pressing the packing 100 toward the back of the through hole 34. By attaching the nut 92, with the pipe 10 inserted into the through hole 34, to the connecting portion 12, the pipe fitting 90 secures the pipe 10 with a stop ring 38, connecting the pipe 10 and the connecting portion 12 (see FIGS. 10 and 12).

[0038] As shown in FIG. 11 , the nut 92 has a retaining portion 40 that retains a packing 100 (a locking portion 102 of the packing 100, described later) inserted into a through hole 34 that extends from the insertion side to the connection side, toward the outer circumferential surface of the piping 10 inserted into the through hole 34. The retaining portion 40 protrudes toward the axial center of the through hole 34 on the far side compared to the inlet side of the through hole 34 where the packing 100 is inserted. The inner diameter of the portion of the through hole 34 where the retaining portion 40 is formed is narrower on the far side than on the inlet side. The retaining portion 40 is an inclined surface that slopes toward the axial center of the through hole 34 as it moves from the inlet side to the far side of the through hole 34, and is formed around the entire circumferential direction of the through hole 34 (see FIG. 14 ). The retaining portion 40 is disposed on the insertion path of the packing 100 inserted into the through hole 34. When the packing 100 is attached to the nut 92, the locking portion 102 that comes into contact with the pressing portion 40 is guided toward the axial center of the through hole 34 as the packing 100 is inserted into the through hole 34, and the pressing portion 40 presses the locking portion 102 radially inward of the through hole 34. The nut 92 also has a second attached portion 94 that is provided on the outer peripheral surface of the insertion side of the nut 92 and is used to attach a pressing member (see FIGS. 11 and 13). The second attached portion 94 in the second embodiment is male-threaded.

[0039] As shown in FIG. 11 , the packing 100 is cylindrical and has an insertion hole 100a through which the pipe 10 is inserted. The packing 100 has a locking portion 102 that abuts against the outer circumferential surface of the pipe 10. The locking portion 102 is formed at the beginning of insertion of the packing 100 into the through-hole 34. The inner circumferential surface of the locking portion 102 protrudes inward (toward the axial center of the insertion hole 100a) from the inner circumferential surface of the packing 100 at the end of insertion into the through-hole 34, and the insertion hole 100a of the packing 100 has a smaller diameter at the beginning of insertion than at the end of insertion. The locking portion 102 is formed in an annular shape that can abut against the entire outer circumferential surface of the pipe 10 (see FIG. 15 ). When the packing 100 is attached to the nut 92, the locking portion 102 seals the entire outer circumferential surface of the pipe 10 and also functions as a seal to prevent water from entering the through-hole 34 in the nut 92. The outer peripheral surface of the locking portion 102 is an inclined surface whose outer diameter increases from the insertion start side of the packing 100 into the through hole 34 toward the insertion end side. When the packing 100 is attached to the through hole 34, the outer peripheral surface of the locking portion 102 abuts against the pressing portion 40 and is pressed inward by the pressing portion 40. Furthermore, when the locking portion 102 abuts against the pressing portion 40, most of the packing 100 is disposed inside the through hole 34 of the nut 92, and a portion of the packing 100 on the insertion end side protrudes from the through hole 34.

[0040] As shown in FIG. 11 , the packing 100 has a protrusion 104 at the base of the locking portion 102 on its outer circumferential surface. The protrusion 104 protrudes from the outer circumferential surface of the packing 100 and is formed in an annular shape that can abut against the entire inner surface of the through hole 34 (see FIG. 15 ). When the packing 100 is attached to the nut 92, the protrusion 104 abuts against the inner surface of the through hole 34, sealing the gap between the nut 92 and the packing 100. The same material as in the first embodiment can be used for the packing 100. For example, if the nut 92 is made of a copper alloy and the piping 10 is an aluminum pipe or a copper pipe, the packing 100 should be made of an insulating material such as rubber.

[0041] As shown in FIG. 11 , the pressing member 110 is formed in the shape of a lid that covers the entrance of the through-hole 34. The pressing member 110 has a hexagonal outer shape (see FIG. 16 ). The pressing member 110 has a through-hole 110a through which the piping 10 passes and a screw-like second mounting portion 112 that engages with the second mounted portion 94 of the nut 92. The through-hole 110a is formed to be larger than the outer diameter of the piping 10. The second mounting portion 112 is a female screw. The pressing member 110 abuts against the insertion end of the packing 100 inserted into the through-hole 34, and by tightening the pressing member 110, the packing 100 is pushed toward the back of the through-hole 34. The material of the pressing member 110 is not particularly limited, but examples thereof include rubber such as IIR (butyl rubber), EPDM (ethylene propylene diene rubber), and NBR (nitrile rubber), and plastics such as polyethylene, cross-linked polyethylene, and polypropylene. For example, if the nut 92 is made of a copper alloy and the pipe 10 is an aluminum pipe or a copper pipe, the pressing member 110 should be made of an insulating material such as rubber.

[0042] The connection of a pipe 10 using a pipe fitting 90 of the second embodiment will be described with reference to Figures 17A to 17D. The stop ring 38 and the connection seal member 58 are pre-assembled to the nut 92 before the connection of the pipe 10 (see Figure 17A). The packing 100 is disposed in the through hole 34 of the nut 92. The pressing member 110 is attached to the nut 92 by engaging the second mounting portion 112 with the second mounted portion 94 of the nut 92. At this time, the packing 100 is disposed in a position on the nut 92 where the locking portion 102 is separated from the holding portion 40 of the nut 92. The pipe 10 is passed through the insertion hole 100a of the packing 100 and inserted into the through hole 34 of the nut 92, and is inserted inside the stop ring 38 until the pipe 10 abuts against the stepped portion 78 of the stop ring 38 (see Figure 17B). At this time, the locking portion 102 of the packing 100 is disengaged from the pressing portion 40 of the nut 92 and does not come into strong contact with the outer peripheral surface of the piping 10, so the position of the piping 10 can be easily changed with respect to the insertion hole 100a (see FIGS. 10 and 11) of the packing 100. Note that the order of inserting the piping 10 from the insertion hole 100a of the packing 100 into the through hole 34 of the nut 32 with the packing 100 loosely attached to the nut 92 (a state in which the pressing portion 40 is not pressing the locking portion 102 to a weak degree) is not limited to this. The packing 100 and the pressing member 110 may be attached to the nut 92 after assembling the packing 100 and the pressing member 110 with the piping 10.

[0043] Next, by rotating the pressing member 110 relative to the nut 92, the packing 100 is pressed by the pressing member 110, which is tightened by the engagement of the threaded second mounting portion 112 of the pressing member 110 and the threaded second mounted portion 94 of the nut 92, and moves toward the back of the through hole 34 (see FIG. 17C). As the locking portion 102 of the packing 100 is inserted into the through hole 34, it comes into contact with the holding portion 40 of the nut 92 and is guided toward the axial center of the through hole 34, and is firmly pressed from the outside against the outer peripheral surface of the piping 10 by the holding portion 40 (see FIG. 10). In this way, the piping 10 is held by the locking portion 102 of the packing 100, and the piping 10 is temporarily fixed in a state where it is positioned relative to the nut 92.

[0044] Next, the nut 92 that temporarily fixes the pipe 10 is attached to the connecting portion 12 (see FIG. 17D). The attachment of the nut 92 to the connecting portion 12 is the same as in the first embodiment.

[0045] The pipe fitting 90 of the second embodiment has the following advantages in addition to the advantages of the first embodiment described above. Because the packing 100 and the pressing member 110 that presses the packing 100 are separate members, even if the packing 100 rotates relative to the nut 92 when the connection part 12 and the nut 92 are attached or detached, the pressing member 110 does not rotate. Therefore, when the connection part 12 and the nut 92 are attached or detached, the pressing member 110 is prevented from loosening, the state in which the pressing member 110 presses the packing 100 can be maintained, and the state in which the packing 100 temporarily fixes the piping 10 can be maintained.

[0046] The pipe fitting 90 of the second embodiment is configured so that the packing 100 is assembled to the nut 92 by meshing the threaded second mounted portion 94 of the nut 92 with the threaded second mounting portion 112 of the pressing member 110. This type of threaded fitting structure between the nut 92 and the pressing member 110 allows the packing 100 and the pressing member 110 to be easily attached to the nut 92. Furthermore, the position of the locking portion 60 in the through hole 34 can be easily adjusted by the amount the pressing member 110 is screwed into the nut 92, and the degree to which the packing 100 secures the piping 10 can be adjusted.

[0047] (Example of change) The present disclosure is not limited to the above-described matters, but may be, for example, as follows: Note that the present disclosure is not limited to the specific descriptions of the embodiments and the following modified examples. (1) In the embodiment, a non-flare fitting that does not require flaring at the end of the pipe is exemplified, but the configuration of the present disclosure can also be applied to a pipe fitting that connects a pipe with a flared end. (2) The pipe fitting of the present disclosure can be used not only for connecting piping for gases through which refrigerants flow, but also for connecting piping for liquids such as water supply and hot water supply. (3) In the embodiment, a connection part provided on the equipment is connected to a pipe, but this is not limited to this. The connection part may be a union that connects a pipe inserted into a nut to another pipe. (4) In the embodiment, the nut and the packing are attached using a screw-fit structure, but this is not limiting and other attachment structures such as a claw-fit structure may also be used. (5) In the embodiment, the pressing portion is an inclined surface, but is not limited to this and may be a curved surface, a stepped surface, or any other shape. (6) Although it is preferable to form the pressing portion around the entire circumference of the through hole as in the embodiment, since it can appropriately press the locking portion of the packing, it is not limited to this, and pressing portions over a partial range in the circumference of the through hole may be formed in one or more locations. In this case, it is preferable to provide an annular sealing portion that abuts on the outer peripheral surface of the pipe in the insertion hole. [Industrial Applicability]

[0048] As described above, the present invention can be used in the field of piping, particularly as a pipe joint for connecting pipes. [Explanation of symbols]

[0049] 10 Piping, 30·90 Pipe fitting, 32·92 Nut, 34 Through hole, 36·100 packing, 36a insertion hole, 40 holding portion, 42 first mounting portion, 60·102 locking portion, 62 first mounting portion, 64 mounting operation portion, 94 second mounting portion, 112 Second mounting part

Claims

1. A pipe joint comprising a nut having a through hole, and a packing disposed between a pipe inserted into the through hole and the nut, The packing has a locking portion that abuts against an outer peripheral surface of the pipe, The nut has a pressing portion that presses the locking portion toward the outer peripheral surface of the pipe inserted into the through hole as the locking portion is inserted into the through hole.

2. 2. The pipe joint according to claim 1, wherein the pressing portion protrudes toward the axial center of the through hole on a deeper side than an entrance side of the through hole into which the locking portion is inserted.

3. 3. The pipe joint according to claim 2, wherein the pressing portion is an inclined surface that inclines toward the axial center of the through hole as it moves from the inlet side to the innermost side of the through hole.

4. the packing has an attachment operation portion that is disposed outside the through hole when the locking portion is inserted into the through hole, the mounting operation portion has an insertion hole into which the piping is inserted, 2. The pipe joint according to claim 1, wherein the locking portion is inclined toward the axial center of the insertion hole from the mounting operation portion toward the tip of the locking portion.

5. The nut has a threaded first mounting portion, 2. The pipe joint according to claim 1, wherein the packing has a threaded first mounting portion that engages with the first mounted portion.

6. 2. The pipe joint according to claim 1, further comprising a pressing member attached to the nut and pressing the packing toward the inner side of the through hole.

7. The nut has a second threaded mounting portion, 7. A pipe joint according to claim 6, wherein the pressing member has a second mounting portion in the form of a screw that engages with the second mounted portion.

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