Pipe joint

Abstract

To provide a pipe joint capable of preventing idling of a fastening fig when fastening a cap to a joint body by the fastening jig, and capable of preventing damage of the cap generated due to the idling of the fastening jig.SOLUTION: A pipe fitting 100 comprises a joint body, and a cap 102 screwed onto the joint body. The cap 102 has a plurality of ribs 202. The plurality of ribs 202 protrude radially outward from an outer peripheral surface 102i of a fourth cylindrical part 102f, extend in an axial direction, and are spaced apart in a circumferential direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, pipe fittings have been used to connect pipes used for cold water supply, hot water supply, air conditioning equipment, etc. in buildings (see, for example, Patent Document 1). The pipe fitting comprises a cylindrical fitting body with an installation recess formed on its inner circumferential surface, a retaining ring that is installed in the installation recess and contacts the outer circumferential surface of a pipe inserted inside the fitting body, and an annular spacer that is arranged on the inner circumferential surface of the fitting body. The spacer is sandwiched between a first retaining ring and a second retaining ring. The first retaining ring is also sandwiched between a base and the spacer. A synthetic resin cap is threaded onto the fitting body. The synthetic resin cap is generally manufactured by injection molding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-139495 Summary of the Invention [Problem to be solved by the invention]

[0004] When screwing the cap onto the joint body, a tightening jig is engaged with the cap and then used to tighten the cap onto the joint body. However, if the clearance between the male thread of the joint body and the female thread of the cap becomes narrow, the torque generated by the male and female threads increases. This can cause the tightening jig to spin freely relative to the cap, making it difficult to tighten the cap. Furthermore, the part that holds the tightening jig in place may be crushed due to the loosening of the tightening jig, and the crushed fragments may get inside the cap and cause water leakage.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a pipe fitting that can prevent the tightening jig from spinning freely when tightening the cap onto the fitting body with the tightening jig, and can prevent damage to the cap that would otherwise be caused by the tightening jig spinning freely. [Means for solving the problem]

[0006] A pipe fitting according to one aspect of the present invention comprises a fitting body and a cap threadedly attached to the fitting body, the cap having a plurality of ribs that protrude radially outward from the outer peripheral surface, extend axially, and are spaced apart circumferentially. [Effects of the Invention]

[0007] According to the present invention, it is possible to prevent the tightening jig from spinning freely when tightening the cap onto the joint body with the tightening jig, and to prevent damage to the cap that would otherwise be caused by the tightening jig spinning freely. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a pipe joint according to an embodiment of the present invention, the perspective view including a partial cross section. [Figure 2] FIG. 1 is an exploded perspective view showing a component configuration of a pipe joint according to an embodiment of the present invention. [Figure 3] FIG. 1 is a front view showing a cap according to an embodiment of the present invention. [Figure 4] FIG. 2 is a side view showing a cap according to an embodiment of the present invention. [Figure 5] FIG. 10 is a front view illustrating the area ratio of a rib according to one embodiment of the present invention. [Figure 6] 6 is an enlarged front view of a portion VI of the cap of FIG. 3. FIG. [Figure 7] 10 is a graph showing the relationship between the number of ribs and cross-sectional area that can prevent damage when tightening the cap in one embodiment of the present invention, and the relationship between the number of recesses and cross-sectional area that can prevent damage when tightening the cap in a comparative example. [Figure 8]FIG. 10 is a front view showing a modified example of a rib provided on the cap according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a pipe joint according to one embodiment of the present invention will be described with reference to the drawings. As shown in Figures 1 and 2, the pipe fitting 100 comprises a fitting body 101, an annular gasket 103a arranged on the inner surface of the fitting body 101, an annular base member 103b arranged on the inner surface of the fitting body 101, an annular spacer 104c arranged on the inner surface of the fitting body 101, a first retaining ring 104a arranged on the inner surface of the fitting body 101, a second retaining ring 104b arranged on the inner surface of the fitting body 101, a resin inner core 105 arranged on the inner surface of the fitting body 101, and a cap 102 arranged at the end of the fitting body 101. The pipe fitting 100 according to this embodiment is a component for connecting a plurality of pipes (pipes) P for water intake, hot water supply, or air conditioning equipment in a building. The pipe fitting 100 and the pipes P connected to this pipe fitting 100 constitute a piping structure.

[0010] The pipe joint 100 comprises a cylindrical joint body 101 and a cap 102 provided at the end of the joint body 101 . Hereinafter, the direction along the central axis of the joint body 101 will be referred to as the axial direction, and the direction intersecting the central axis in a plan view of the joint body 101 from the axial direction will be referred to as the radial direction. Also, the direction going around the central axis in the plan view will be referred to as the circumferential direction.

[0011] A step 113 is formed on the inner peripheral surface of the axial end of the joint body 101. The step 113 protrudes radially inward from the inner peripheral surface of the joint body 101. The step 113 is provided around the entire circumference in the circumferential direction. At the step 113, the inner diameter of the joint body 101 gradually (step-wise) reduces from the outside to the inside in the axial direction. An incore 105, which is formed separately from the joint body 101, abuts against the step 113. Hereinafter, the portion of the joint body 101 from the end face of the joint body 101 to the step 113 will be referred to as the open end of the joint body 101.

[0012] An outer flange portion 101b and a male thread portion 101c are formed on the outer peripheral surface of each of both axial end portions of the joint body 101. The outer flange portion 101b protrudes radially outward from the joint body 101. The outer flange portion 101b extends around the entire outer circumferential surface of the joint body 101. The male thread portion 101c is formed on the outer peripheral surface of the joint body 101 at a portion located axially outward of the outer flange portion 101b (that is, closer to the end of the joint body 101).

[0013] The cap 102 is cylindrical in shape and has an outer diameter that gradually decreases in the axial direction. The cap 102 includes a first tube 102a having an internal thread formed on the inner peripheral surface thereof, and a second tube 102b located axially outward of the first tube 102a. The first tube 102a has a female thread that is threaded onto the male thread portion 101c. A step 102d is provided on the inner circumference of the cap 102 at a portion corresponding to the boundary between the first tube 102a and the second tube 102b. The step 102d extends around the entire circumference. The step 102d contacts or is close to the end face of the joint body 101 that faces outward in the axial direction.

[0014] The second tube 102b has a smaller diameter than the first tube 102a. The second tube 102b extends axially outward from the first tube 102a. The second tube 102b has a third tube portion 102e and a fourth tube portion 102f. The third tube portion 102e is provided at the axially outer end of the first tube 102a. The third tube portion 102e has an outer diameter that gradually decreases as it extends axially outward from the end of the first tube 102a. The fourth tube portion 102f is provided at the axially outer end of the third tube portion 102e. The fourth tube portion 102f has an outer diameter smaller than that of the first tube 102a. The inner circumferential surfaces 102g of the third tube portion 102e and the fourth tube portion 102f are formed so that the pipe P can be inserted therein and can stably support the pipe P.

[0015] The fourth cylindrical portion 102f has a plurality of recesses 200 (see FIGS. 3 and 4) on the end surface 102h. The fourth cylindrical portion 102f also has gate marks 201 (see FIG. 3) in the recesses 200. The fourth cylindrical portion 102f also has a plurality of ribs 202 on the outer circumferential surface 102i. The recesses 200, gate marks 201, and ribs 202 will be described in detail later. Note that the recesses 200 and gate marks 201 are not shown in FIGS. 1 and 2.

[0016] In the pipe fitting 100, an accommodating recess 106 for accommodating the watertight portion 103 and the fixing portion 104 is formed between the fitting body 101 and the cap 102. The accommodating recess 106 is formed between the step 102d and the end face of the fitting body 101 that faces outward in the axial direction. The accommodating recess 106 extends around the entire circumferential direction.

[0017] The joint body 101 is formed, for example, by injection molding of a synthetic resin material, or by cutting, casting, or forging of a metal material. The cap 102 is formed, for example, by injection molding of a synthetic resin material, or by cutting, casting, or forging of a metal material. The synthetic resin material can be selected arbitrarily based on quality design depending on the application, such as cross-linked polyethylene, polybutene, polyvinyl chloride (PVC), polysulfone resin (PSU), polycarbonate resin (PC), polyamide resin (PA), polyacetal resin (POM), polyphenylsulfone resin (PPSU), polyphenylene sulfide resin (PPS), glass fiber reinforced PPS, polyvinylidene fluoride (PVDF), etc. Other processing methods such as cutting and fusion may also be used. The metal material can be arbitrarily selected from stainless steel, low alloy steel, carbon steel, low temperature carbon steel, low temperature alloy steel, brass, gunmetal, aluminum alloy, magnesium alloy, etc. based on quality design according to the intended use.

[0018] At each axial end of the pipe fitting 100, a packing 103a, a base member 103b, a retaining ring 104a, a spacer 104c, and a retaining ring 104b are provided in this order toward the end of the fitting body 101. In other words, the fixing part 104 is located closer to the end than the watertight part 103. The packing 103a and the base member 103b constitute a watertight portion 103. The watertight portion 103 prevents the contents of the pipe P from leaking out from the pipe joint 100. The retaining ring 104a, the spacer 104c, and the retaining ring 104b constitute the fixing part 104. The pipe P inserted into the pipe fitting 100 is fixed to the pipe fitting 100 by the fixing part 104.

[0019] The packing 103a is disposed on the inner peripheral surface of the joint body 101. In the illustrated example, one packing 103a is provided, but multiple packings 103a may be provided spaced apart in the axial direction. The packing 103a is annular with a circular cross section. The packing 103a extends around the entire circumference in the circumferential direction. In the illustrated example, an O-ring is used as the packing 103a. The packing 103a can be made of rubber materials such as ethylene propylene diene rubber (EPDM), fluororubber (FKM), vinyl methyl silicone rubber (VMQ), acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), and chloroprene rubber (CR).

[0020] The base member 103b is disposed between the packing 103a and the retaining ring 104a. The base member 103b prevents the packing 103a and the retaining ring 104a from coming into contact with each other. The base member 103b is formed in an annular shape. The base member 103b extends over the entire circumference in the circumferential direction. The base member 103b is fitted into the open end of the joint body 101. The base member 103b contacts a first step, which is a step provided on the inner peripheral surface of the joint body 101. The base member 103b is hooked onto the first step of the joint body 101 from the outside in the axial direction. The inner diameter of the base member 103b is larger than the inner diameter of the packing 103a.

[0021] The base member 103b is formed by, for example, injection molding of a synthetic resin material, or cutting, casting, or forging of a metal material. The synthetic resin material can be selected arbitrarily based on quality design depending on the application, such as cross-linked polyethylene, polybutene, polyvinyl chloride (PVC), polysulfone resin (PSU), polycarbonate resin (PC), polyamide resin (PA), polyacetal resin (POM), polyphenylsulfone resin (PPSU), polyphenylene sulfide resin (PPS), glass fiber reinforced PPS, polyvinylidene fluoride (PVDF), etc. Other processing methods such as cutting and fusion may also be used. The metal material can be arbitrarily selected from stainless steel, low alloy steel, carbon steel, low temperature carbon steel, low temperature alloy steel, brass, gunmetal, aluminum alloy, magnesium alloy, etc. based on quality design according to the intended use.

[0022] The retaining rings 104a, 104b and spacer 104c are arranged on the axial outside of the base member 103b. The retaining rings 104a, 104b and spacer 104c are arranged in an accommodating recess of the joint body 101. The accommodating recess is located axially outside of the first step. The retaining rings 104a, 104b and spacer 104c are arranged in the accommodating recess with some axial play. The retaining ring 104a, spacer 104c and retaining ring 104b are arranged in this order from the axial outside to the axial inside. The spacer 104c is arranged in the accommodating recess and sandwiched axially between the retaining ring 104a and the retaining ring 104b.

[0023] Next, the recess 200, the gate mark 201, and the rib 202 will be described in detail with reference to FIGS. As shown in FIGS. 3 and 4, the cap 102 has a plurality of recesses 200, gate marks 201, and a plurality of ribs 202 in the fourth cylindrical portion 102f. The recesses 200 are provided at equal intervals in the circumferential direction on the end surface 102h of the fourth cylindrical portion 102f (i.e., the cap 102). In the embodiment, an example in which four recesses 200 are provided is described, but the number of recesses 200 can be selected arbitrarily. The recesses 200 open to the end surface 102h and are formed in a U-shaped recess inward in the axial direction. Specifically, the recesses 200 have a pair of wall portions 211 and a bottom portion 212.

[0024] The pair of wall portions 211 are spaced apart in the circumferential direction and formed along the axial direction. The bottom portion 212 is provided on the opposite side of the pair of wall portions 211 from the end face 102h. The bottom portion 212 extends in the circumferential direction and is connected to the pair of wall portions 211. The recessed portion 200 is formed by the pair of wall portions 211 and the bottom portion 212 so as to open to the end face 102h and recess inward in the axial direction in a U-shape. Furthermore, the recessed portion 200 is formed as a step that penetrates in the radial direction.

[0025] Gate marks 201 are provided on the bottoms 212 of the multiple recesses 200. The gate marks 201 are marks left when solidified resin is cut at a gate that fills the cavity with molten resin during injection molding of the cap 102. The gate marks 201 may remain, for example, protruding in the axial direction from the bottoms 212 of the recesses 200 toward the end face 102h.

[0026] A plurality of ribs 202 are provided on the outer peripheral surface 102i of the fourth cylindrical portion 102f (i.e., the cap 102). Specifically, the plurality of ribs 202 protrude radially outward from the outer peripheral surface 102i of the fourth cylindrical portion 102f and extend in the axial direction. The plurality of ribs 202 have a first end surface 202a facing outward in the axial direction and a second end surface 202b facing inward in the axial direction. The first end surface 202a is formed flush with the end surface 102h of the fourth cylindrical portion 102f in the radial direction. The second end surface 202b is connected to the third cylindrical portion 102e. The ribs 202 are formed to a sufficient length so as to extend axially along the outer peripheral surface 102i, thereby providing a highly rigid portion. Furthermore, the plurality of ribs 202 are provided at equal intervals in the circumferential direction of the fourth cylindrical portion 102f (i.e., the cap 102). In the embodiment, an example in which four ribs 202 are provided will be described, but the number of ribs 202 can be selected arbitrarily.

[0027] The multiple ribs 202 are provided between the multiple recessed portions 200 in the circumferential direction. That is, the recessed portions 200 and the ribs 202 are arranged alternately in the circumferential direction. The rib 202 has a pair of side walls 215 and an outer wall 216. The pair of side walls 215 are provided at an interval in the circumferential direction. The outer wall 216 is connected to radially outer ends of the pair of side walls 215. The outer wall 216 is formed flat. That is, the rib 202 is formed into a polygonal shape that protrudes radially outward by the pair of side walls 215 and the outer wall 216 when viewed in the axial direction.

[0028] Incidentally, when the cap 102 is injection molded, it is conceivable that a weld portion 218 will be formed between the gate marks 201 in the circumferential direction. The weld portion 218 is a portion where the molten resin that is injected into the cavity from a pair of gates joins together when the cap 102 is injection molded. In the illustrated example, a plurality of gates that inject the molten resin into the cavity are provided at positions corresponding to the circumferential direction of the cap 102 (i.e., at the bottoms 212 of the plurality of recesses 200). The weld portion 218 is located between the plurality of gates that are provided in the circumferential direction.

[0029] In the embodiment, an example is described in which four welds 218 are formed between the gate marks 201, but it is sufficient to form at least one weld 218. The weld 218 may crack, for example, when an impact load F is applied instantaneously from the radial outside of the cap. Here, the multiple ribs 202 are provided between the multiple recesses 200 in the circumferential direction. Therefore, it is possible to have multiple ribs 202 in the weld portion 218. In the embodiment, an example in which multiple ribs 202 are provided corresponding to four weld portions 218 will be described, but at least one of the multiple ribs 202 may be provided in the weld portion 218.

[0030] Next, the area of ​​the rib 202 that can be used to fasten the cap 102 by engaging a fastening jig with the rib 202 will be described with reference to FIG. As shown in Fig. 5, the multiple ribs 202 are arranged so as to be included within the range of a light gray annular portion 220. The annular portion 220 is formed by a first circle 221 that is tangent to the radially outer outer surfaces of the multiple ribs 202, and a second circle 222 that is along the outer peripheral surface 102i of the fourth cylindrical portion 102f. The area of ​​the annular portion 220 is calculated by subtracting the outer diameter area of ​​the first circle 221 from the inner diameter area of ​​the second circle 222. Hereinafter, the area of ​​the annular portion 220 will be described as the "peripheral area." The area of ​​the rib 202 included in the annular portion 220 is determined as the area projected in the axial direction. Hereinafter, the area of ​​the rib 202 projected in the axial direction will be referred to as the "rib area."

[0031] Table 1 shows the relationship between the area of ​​the ribs 202 and the number of ribs 202 that can fasten the cap 102 by engaging a fastening jig with the ribs 202. Specifically, when the nominal diameter of the cap 102 is Φ10 to Φ20 and two, four, or eight ribs 202 are provided on the fourth cylindrical portion 102f of the cap 102, the table shows the ratio of the rib area of ​​the ribs 202 that can fasten the cap 102. The rib area ratio is [(number of ribs 202) × (rib area)] / (peripheral area) It is expressed as:

[0032] [Table 1]

[0033] As shown in Figure 5 and Table 1, when the nominal diameter of the cap 102 is Φ10, the outer diameter area is 384.8 mm 2 , inner diameter area 64.6mm 2 , peripheral area 320.2mm 2 , rib area 6mm 2 Under these conditions, when two ribs 202 are provided, the ratio of the rib area to the peripheral area is 3.7%, and the cap 102 can be tightened. When four ribs 202 are provided, the ratio of the rib area to the peripheral area is 7.5%, and the cap 102 can be tightened. When eight ribs 202 are provided, the ratio of the rib area to the peripheral area is 15.0%, and the cap 102 can be tightened.

[0034] When the nominal diameter of cap 102 is Φ13, the outer diameter area is 536.4 mm 2 , inner diameter area 80.2mm 2 , peripheral area 456.2mm 2 , rib area 6mm 2 Under these conditions, when two ribs 202 are provided, the ratio of the rib area to the peripheral area is 2.6%, and the cap 102 can be tightened. When four ribs 202 are provided, the ratio of the rib area to the peripheral area is 5.3%, and the cap 102 can be tightened. When eight ribs 202 are provided, the ratio of the rib area to the peripheral area is 10.5%, and the cap 102 can be tightened.

[0035] When the nominal diameter of the cap 102 is Φ16, the outer diameter area is 743.7 mm 2 , inner diameter area 132.7mm 2 , peripheral area 611.1mm 2 , rib area 7.2mm 2Under these conditions, when two ribs 202 are provided, the ratio of the rib area to the peripheral area is 2.4%, and the cap 102 can be tightened. When four ribs 202 are provided, the ratio of the rib area to the peripheral area is 4.7%, and the cap 102 can be tightened. When eight ribs 202 are provided, the ratio of the rib area to the peripheral area is 9.4%, and the cap 102 can be tightened.

[0036] When the nominal diameter of the cap 102 is Φ20, the outer diameter area is 1066.5 mm 2 , inner diameter area 177.3mm 2 , peripheral area 889.2mm 2 , rib area 7.5mm 2 Under these conditions, when two ribs 202 are provided, the ratio of the rib area to the peripheral area is 1.7%, and the cap 102 can be tightened. When four ribs 202 are provided, the ratio of the rib area to the peripheral area is 3.4%, and the cap 102 can be tightened. When eight ribs 202 are provided, the ratio of the rib area to the peripheral area is 6.7%, and the cap 102 can be tightened.

[0037] From the relationship between the area of ​​the ribs 202 capable of tightening the cap 102 and the number of ribs 202 shown in Table 1, it can be seen that the rib area ratio is minimum at 1.7% and maximum at 15.0%. Specifically, when the nominal diameter of the cap 102 is Φ20 and two ribs 202 are provided, the ratio of the rib area to the peripheral area is minimum at 1.7%. On the other hand, when the nominal diameter of the cap 102 is Φ10 and eight ribs 202 are provided, the ratio of the rib area to the peripheral area is maximum at 15.0%. Therefore, the ratio of the rib area to the peripheral area is set to 1.5 to 20%. By setting the ratio of the rib area to the peripheral area to 1.5 to 20%, the tightening torque from the tightening jig can be transmitted to the cap 102 via the ribs 202.

[0038] Next, the height H and width W of the plurality of ribs 202 will be described with reference to FIG. As shown in Fig. 6, the height H of the rib 202 in the radial direction is 1.0 to 5.0 mm. This allows a tightening torque to be applied to the rib 202 effectively when tightening the cap 102 with a tightening jig of an assembly machine. It is also preferable that the height H of the rib 202 is 1.5 to 3.0 mm. This allows a tightening torque to be applied to the rib 202 even more effectively.

[0039] Furthermore, the rib 202 has a circumferential width W of 2.0 to 5.0 mm. This allows the rib 202 to effectively withstand the tightening torque when the cap 102 is tightened with a tightening jig of an assembly machine. Furthermore, it is preferable that the width W of the rib 202 be 3.0 to 5.0 mm. This allows the rib 202 to even more effectively withstand the tightening torque.

[0040] Next, the number of ribs 202 for tightening the cap 102 will be described in detail with reference to Figures 3 and 7. Below, an example in which a tightening tool is engaged with the ribs 202 to tighten the cap 102 will be described as an embodiment. Also, an example in which a tightening tool is engaged with the recesses 200 to tighten the cap 102 will be described as a comparative example. FIG. 7 is a graph showing the relationship between the number of ribs and cross-sectional area that can prevent damage when tightening the cap in an embodiment, and the relationship between the number of recesses and cross-sectional area that can prevent damage when tightening the cap in a comparative example.

[0041] In FIG. 7, the vertical axis represents the cross-sectional area (mm 2 ) and the vertical axis indicates the cross-sectional area (mm 2 ) is shown. Hereinafter, the cross-sectional area of ​​the rib 202 in the circumferential direction will be referred to as the "cross-sectional area of ​​the rib." The "cross-sectional area of ​​the rib" is an area equivalent to the "rib area" shown in Table 1. The rib 202 extends in the axial direction, and is formed to have a sufficient length in the axial direction. Furthermore, the cross-sectional area (area) of the wall portion 211 in the recess 200 will be referred to as the "cross-sectional area of ​​the recess." The horizontal axis indicates the number of ribs 202 used in the embodiment, and the horizontal axis indicates the number of recesses 200 used in the comparative example.

[0042] Graph G1 is a graph showing an embodiment in which the cap 102 is tightened by engaging a tightening jig with the rib 202. The rib 202 is provided on the cap 102 with a nominal diameter of Φ20. Graph G2 is a graph showing a comparative example in which the cap 102 is tightened by engaging a tightening jig with the recess 200. The recess 200 is provided on the cap 102 with a nominal diameter of Φ20. G3 is a threshold value indicating the cross-sectional area of ​​the rib at which damage (curling) occurs when tightening the cap in the embodiment. G3 is also a threshold value indicating the cross-sectional area of ​​the recess at which damage occurs when tightening the cap in the comparative example. If the cross-sectional area of ​​the rib or recess is less than G3, damage occurs when tightening the cap 102. On the other hand, if the cross-sectional area of ​​the rib or recess is G3 or more, damage can be prevented from occurring when tightening the cap 102.

[0043] 7, according to the graph G1 of the embodiment, when tightening the cap 102, for example, by tightening two or more ribs 202 with a tightening jig, damage to the ribs 202 can be prevented. That is, according to the embodiment, by providing two to eight ribs on the cap 102, the cap 102 can be tightened well with the tightening jig. On the other hand, in the graph G2 of the comparative example, when tightening the cap 102, damage to the recesses cannot be prevented unless four or more recesses 200 are tightened with the tightening jig.

[0044] That is, the cross-sectional area of ​​the ribs 202 used in the embodiment is larger than the cross-sectional area of ​​the recesses 200 used in the comparative example. Therefore, the tightening torque of the tightening jig can be transmitted to the ribs 202 in an efficient manner. Thus, by providing two to eight ribs 202 on the fourth cylindrical portion 102f of the cap 102, the tightening jig can be engaged with the ribs 202, allowing the cap 102 to be tightened in an efficient manner with the tightening jig. Preferably, by providing two, four, or eight ribs 202 on the fourth cylindrical portion 102f, the tightening torque of the tightening jig can be transmitted to each rib 202 in a balanced manner.

[0045] According to the pipe fitting 100 of the embodiment described above, as shown in FIGS. 3 and 4, the fourth cylindrical portion 102f of the cap 102 has multiple ribs 202. The multiple ribs 202 protrude radially outward from the outer peripheral surface 102i of the fourth cylindrical portion 102f and extend axially. The multiple ribs 202 are evenly spaced apart around the circumference of the fourth cylindrical portion 102f. Therefore, a tightening jig can be engaged with the multiple ribs 202 and used to tighten the cap 102 to the fitting body 101 (see FIGS. 1 and 2). The ribs 202 are highly rigid. This allows the tightening torque of the tightening jig to be transmitted to the cap 102 via the multiple ribs 202. Therefore, spinning of the tightening jig can be prevented when tightening the cap 102 to the fitting body 101 with the tightening jig. As a result, the cap 102 can be easily screwed onto the fitting body 101.

[0046] Furthermore, by preventing the tightening jig from spinning freely, it is possible to prevent damage to the cap 102 (specifically, the plurality of ribs 202) that would otherwise occur due to the tightening jig spinning freely. This prevents damaged pieces from entering the inside of the cap 102 and becoming a cause of water leakage.

[0047] Furthermore, ribs 202 are provided at the weld portion 218. It is conceivable that the weld portion 218 may crack due to, for example, an impact load F that is momentarily applied from the radially outer side of the cap 102. Therefore, the ribs 202 are provided at the weld portion 218 to reinforce the weld portion 218. This increases the impact resistance of the weld portion 218. This makes it possible to prevent the cap 102 from cracking at the weld portion 218, for example, when an impact load F is momentarily applied to the weld portion 218 from the radially outer side.

[0048] 5, the rib area of ​​the multiple ribs 202 projected in the axial direction is set to a ratio of 1.5 to 20% of the peripheral area of ​​the annular portion 220. This makes it possible to enlarge the shape of the ribs 202 and ensure the strength of the ribs 202. This allows the tightening torque of the tightening jig to be efficiently transmitted to the cap 102 via the multiple ribs 202.

[0049] 6, the height H of the ribs 202 is set to 1.0 to 5.0 mm, and preferably 1.5 to 3.0 mm. This allows the tightening jig to be securely locked onto the ribs 202. This allows the tightening torque of the tightening jig to be efficiently transmitted to the cap 102 via the multiple ribs 202.

[0050] Furthermore, the width W of the ribs 202 is set to 2.0 to 5.0 mm, and preferably 3.0 to 5.0 mm. This increases the strength of the ribs 202 against the tightening torque applied from the circumferential direction. This allows the tightening torque applied by the tightening jig to be effectively transmitted to the cap 102 via the multiple ribs 202.

[0051] 3 and 4, the end face 102h of the fourth cylindrical portion 102f has a plurality of recesses 200. That is, the end face 102h of the fourth cylindrical portion 102f has steps recessed in the axial direction formed at intervals in the circumferential direction. Here, when the pipe P (see FIG. 1) is inserted into the cap 102, the incore 105 is designed to protrude by several millimeters at the end surface 102h of the fourth cylindrical portion 102f. Therefore, by providing a step (i.e., the recess 200) on the end surface 102h, the recess 200 functions as a window through which the incore 105 can be seen. As a result, with the pipe P inserted into the cap 102, the installer can visually confirm through the recess 200 that the incore 105 has been placed on the inner circumferential surface of the fitting body 101 (see FIG. 1). In other words, the installer can perform the installation reliably by visually confirming that the incore 105 has been inserted.

[0052] In addition, a recess 200 is provided on the end surface 102h of the fourth cylindrical portion 102f, and a gate mark 201 is provided in the recess 200. Therefore, the gate mark 201 can be contained inside the recess 200. In other words, the gate mark 201 can be prevented from protruding from the surface of the cap 102. This makes it possible to prevent the pipe P from being damaged by the gate mark 201 when inserting (connecting) the pipe P into the cap 102 at a construction site, for example.

[0053] Moreover, the recesses 200 and the ribs 202 are arranged alternately in the circumferential direction. This enhances the reinforcing effect of the ribs 202 on the recesses 200. Furthermore, by arranging the recesses 200 and the ribs 202 alternately in the circumferential direction, the ribs 202 can be arranged apart from the recesses 200 in the circumferential direction. Alternatively, the ribs 202 can be arranged so as not to overlap the recesses 200 in the radial direction. This ensures the strength of the ribs 202.

[0054] (Variation) Next, a modified example of the rib 202 of the embodiment will be described with reference to FIG. As shown in FIG. 8 , the ribs 302 of the modified example are provided on the fourth cylindrical portion 102f of the cap 102 as multiple ribs, that is, three ribs 302. The three ribs 302 are provided at equal intervals in the circumferential direction on the outer peripheral surface 102i of the fourth cylindrical portion 102f. When viewed in the axial direction, the rib 302 is formed into a U-shape that protrudes radially outward by a pair of side walls 303 and a curved outer wall 304. The recesses 200 are arranged alternately in the circumferential direction around the ribs 302. Each rib 302 is sandwiched between two recesses 200 in the circumferential direction. Each rib 302 is provided to correspond to a weld portion 218 formed by gate marks 201 provided in these two recesses 200. According to the rib 302 of the modified example, it is possible to obtain the same functions and effects as the rib 202 of the embodiment.

[0055] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0056] For example, the recess 200, the gate mark 201, and the like may be omitted.

[0057] In addition, the components in this embodiment can be replaced with well-known components as appropriate, without departing from the spirit of the present invention.

[0058] (Addendum) <1> A pipe fitting according to one aspect of the present invention comprises a fitting body and a cap threadedly attached to the fitting body, the cap having a plurality of ribs that protrude radially outward from the outer peripheral surface, extend axially, and are spaced apart circumferentially.

[0059] According to the pipe joint, the cap has multiple ribs that protrude radially outward from the outer peripheral surface of the cap and extend axially. The multiple ribs are also spaced apart circumferentially around the cap. Therefore, a tightening jig can be engaged with the multiple ribs and used to tighten the cap to the joint body. The ribs are highly rigid. This allows the tightening torque of the tightening jig to be transmitted to the cap via the multiple ribs. Therefore, freewheeling of the tightening jig can be prevented when tightening the cap to the joint body with the tightening jig. As a result, the cap can be easily screwed onto the joint body. Furthermore, by preventing the tightening jig from spinning freely, damage to the cap caused by the tightening jig can be prevented, which prevents damaged pieces from getting inside the cap and causing water leakage.

[0060] <2> the above <1> In the pipe joint according to the above aspect, at least one of the plurality of ribs may be provided in the weld portion.

[0061] Here, it is conceivable that the weld portion may crack due to, for example, an impact load momentarily applied from the radially outer side of the cap. Therefore, a rib is provided at the weld portion. Therefore, the weld portion can be reinforced with the rib to increase the impact resistance of the weld portion. This makes it possible to prevent the cap from cracking at the weld portion, for example, when an impact load momentarily applies to the weld portion from the radially outer side.

[0062] <3> the above <1> or <2> In the pipe fitting according to the above, the rib area of ​​the plurality of ribs projected in the axial direction may be 1.5 to 20% of the annular peripheral area formed by a first circle tangent to outer surfaces on the radially outer side of the plurality of ribs and a second circle along the outer peripheral surface of the cap.

[0063] According to the pipe fitting, the rib shape can be enlarged by making the rib area 1.5 to 20% of the annular peripheral area. This ensures the strength of the rib. As a result, the tightening torque of the tightening jig can be efficiently transmitted to the cap via the rib.

[0064] <4> the above <3> In the pipe joint according to the above, the rib may have a height in the radial direction of 1.0 to 5.0 mm.

[0065] According to the pipe joint, by setting the rib height to 1.0 to 5.0 mm, the tightening jig can be securely locked onto the rib, thereby allowing the tightening torque from the tightening jig to be efficiently transmitted to the cap via the rib.

[0066] <5> the above <4> In the pipe joint according to the above, the rib may have a circumferential width of 2.0 to 5.0 mm.

[0067] According to the pipe joint, by setting the rib width to 2.0 to 5.0 mm, the strength of the rib can be increased against the tightening torque applied from the circumferential direction, thereby enabling the tightening torque from the tightening jig to be effectively transmitted to the cap via the rib.

[0068] <6> the above <1> In the pipe joint according to the above aspect, the cap may have a plurality of recesses.

[0069] Here, an inner core is placed on the inner peripheral surface of the fitting body. The inner core is designed to protrude a few millimeters from the end face of the cap when the pipe is inserted into the cap. Therefore, the cap is provided with multiple recesses. Therefore, when the pipe is inserted into the cap, the recesses function as windows. This allows the installer to visually confirm that the inner core has been placed through the recesses. In other words, the installer can perform the installation reliably by visually confirming that the inner core 105 has been inserted.

[0070] <7> the above <6> In the pipe joint according to the above aspect, the recess may be formed on an end surface of the cap, and the recess may have a gate mark.

[0071] According to the pipe joint, a recess is provided on the end surface of the cap, and a gate mark is provided in the recess. This allows the gate mark to be contained within the recess. In other words, the gate mark can be prevented from protruding from the surface of the cap. This makes it less likely that the pipe will be damaged by the gate mark when inserting (connecting) the pipe into the cap at the construction site, for example.

[0072] <8> the above <6> or <7> In the pipe joint according to the above aspect, the recesses and the ribs may be arranged alternately in the circumferential direction.

[0073] According to the pipe joint, by arranging the recesses and the ribs alternately in the circumferential direction, the reinforcing effect of the ribs on the recesses can be enhanced. Also, by arranging the recesses and the ribs alternately in the circumferential direction, the ribs can be arranged apart from the recesses in the circumferential direction. Alternatively, the ribs can be arranged so as not to overlap the recesses in the radial direction. This ensures the strength of the ribs. [Explanation of symbols]

[0074] 100...Pipe fittings 101...Joint body 102...Cap 102f...4th cylinder part 102h...End face (end face of cap) 102i…Outer surface 200...recess 201...Gate remains 202...Rib 218...weld section 221...1st Yen 222...Second Circle H: Rib height W…Rib width

Claims

1. A joint body, A cap screwed onto the joint body, The cap has a plurality of ribs that protrude radially outward from an outer circumferential surface, extend axially, and are circumferentially spaced apart.

2. The pipe fitting according to claim 1 , wherein at least one of the plurality of ribs is provided in a weld portion.

3. 3. The pipe fitting according to claim 1, wherein a rib area of ​​the plurality of ribs projected in the axial direction is a ratio of 1.5 to 20% to an annular peripheral area formed by a first circle tangent to radially outer surfaces of the plurality of ribs and a second circle along an outer peripheral surface of the cap.

4. 4. The pipe joint according to claim 3, wherein the rib has a radial height of 1.0 to 5.0 mm.

5. 5. The pipe joint according to claim 4, wherein the rib has a circumferential width of 2.0 to 5.0 mm.

6. The fitting of claim 1 , wherein the cap includes a plurality of recesses.

7. The pipe joint according to claim 6 , wherein the recess is formed on an end surface of the cap, and the recess has a gate mark.

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