Fluid pipe coupling device and coupling

Abstract

To provide a fluid pipe joint device capable of confirming a required amount of fastening of a connection nut, and capable of preventing loosening of the connection nut by maintaining the required amount of the fastening.SOLUTION: A fluid pipe joint device 3 includes a fluid pipe joint 3a and a locking tool 20. The fluid pipe joint 3a includes a first joint member 5 and a second joint member 10. The first joint member 5 includes a first connecting portion 7, and the first connecting portion 7 has a first shaft 8 and a connection nut 9. The second joint member 10 has a second shaft 13 (second connecting portion 12). A male screw 13a is formed on an outer periphery of the second shaft 13, and the first connecting portion 7 and the second connecting portion 12 are connected with each other by screwing of the connection nut 9 and the male screw 13a. The locking tool 20 includes a nut abutment portion 20a abutting on a backward side end face 9a of the connection nut 9, and regulates movement of the connection nut 9 to the male screw 13a in a retreat direction 22 in a state of being attached to the fluid pipe joint 3a.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to fluid coupling devices and to connections between members in couplings. [Background technology]

[0002] Conventionally, a pipe joint has been used at the end of a drainage path between an air conditioner's drain outlet and a drainage pipe (see, for example, Patent Document 1). As shown in Fig. 10, this pipe joint 33 connects a pipe body 31 and a drainage pipe 32, and is composed of a first connector 34 on the pipe body 31 side and a second connector 35 on the drainage pipe 32 side. Here, when connecting the first connector 34 and the second connector 35, a connecting nut 34a rotatably attached to the first connector 34 is threaded onto a male thread portion 35a formed on the second connector 35, thereby connecting the two connectors 34, 35 to each other. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-127671 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the conventional pipe joint 33, there was a risk of water leakage if the connecting nut 34a was not tightened enough, or if the connecting nut 34a became loose due to vibrations caused by the flow of drainage water or vibrations from the drainage motor.

[0005] This invention has been made to solve the above-mentioned conventional drawbacks, and its purpose is to provide a fluid pipe coupling device and coupling that can confirm the required amount of tightening of the connecting nut and can maintain the required amount of tightening to prevent the connecting nut from loosening. [Means for solving the problem]

[0006] In order to achieve the above object, the fluid pipe coupling device and coupling according to the present invention have the following configuration: Book A fluid pipe coupling device according to the present invention comprises a fluid pipe coupling and a locking device. The fluid pipe coupling comprises a first coupling member and a second coupling member that are coupled to each other. The first coupling member comprises a first connection portion to which a first fluid pipe is connected and a first coupling portion having a first shaft portion, and has a fluid flow passage provided therein. The first coupling portion has a connecting nut fitted to the outer periphery of the first shaft portion so as to be rotatable and unable to slip out from the tip side of the first shaft portion. The second coupling member comprises a second connection portion to which a second fluid pipe is connected and a second coupling portion having a second shaft portion, and has a fluid flow passage provided therein. The second shank has an outer periphery formed with a male thread that threadably engages with the connecting nut. The first and second coupling portions are coupled together by the connection nut and the male thread, and the flow passage of the first fluid pipe and the flow passage of the second fluid pipe are connected to each other via the flow passages of the first and second coupling members. The locking device has a nut abutment that abuts against the rear end face of the connecting nut, opposite the tip of the first shank. The locking device can be attached to the fluid pipe coupling in a direction intersecting the axial direction of the connecting nut with the nut abutment facing the connecting nut that threads onto the male thread. When attached, the locking device restricts backward movement of the connecting nut relative to the male thread. The locking device can be attached to the fluid pipe coupling only when the connecting nut is threaded onto the male thread to a specified engagement position.

[0007] According to this fluid pipe coupling device, the fluid pipe coupling includes a first coupling member and a second coupling member. The first coupling member includes a first coupling portion, and the second coupling member includes a second coupling portion. The connecting nut of the first coupling portion is threadedly engaged with the male thread portion of the second coupling portion, thereby connecting the first coupling portion and the second coupling portion, and ultimately the first coupling member and the second coupling member. The locking device can be attached to the fluid pipe coupling only when the connecting nut is threaded onto the male thread portion up to a specified engagement position. When the locking device is attached to the fluid pipe coupling, the nut abutment portion of the locking device abuts against the rear end face of the connecting nut, which is opposite to the tip of the first shank, thereby restricting movement of the connecting nut in the backward direction relative to the male thread portion.

[0008] Also, The present invention In the fluid pipe coupling device, the second coupling member has a locked portion on the base end side of the male thread portion. The locking device has a locking portion that locks onto the locked portion when attached to the fluid pipe coupling, and the locking portion and the nut abutment portion restrict movement of the connecting nut in the backward direction relative to the male thread portion. Configuration is suggested .

[0009] Also, The above configuration In the locking device, a part of the annular portion is missing, and the missing portion forms an opening for receiving the connecting nut and the locked portion, forming a roughly C-shape, and the nut abutment portion and the locking portion are located at both ends, and the space between the nut abutment portion and the locking portion forms an accommodation groove portion in which the connecting nut and the locked portion are accommodated. the law of nature The locking device can rotate freely around the outer periphery of the connecting nut in an attached state in which the connecting nut and the locked portion are accommodated. This allows the orientation of the opening to be changed by rotating the locking device after it is attached. Configuration is suggested .

[0010] Also, The present invention In the fluid pipe coupling device, a heat insulating material is provided which covers at least a part of the fluid pipe coupling together with the locking device when the locking device is attached to the fluid pipe coupling. Configuration is suggested .

[0011] Also, The present invention In the fluid pipe coupling device, the locking tool is colored differently from the fluid pipe coupling. Configuration is suggested .

[0012] Also, Book A coupling according to the present invention comprises a coupling member and a locking device. The coupling member includes a connection portion to which a fluid pipe is connected and a coupling portion having a shaft portion and an internal fluid flow passage. The coupling portion has a connecting nut fitted to the outer periphery of the shaft portion so as to be free to rotate and unable to slip out from the tip end of the shaft portion. The connecting nut is threadably engageable with a male thread portion formed on the outer periphery of a shaft portion of another coupling portion having an internal fluid flow passage. The locking device includes a nut abutting portion that abuts against the rear end face of the connecting nut, opposite the tip end of the shank. The locking device is attachable to the coupling member and the other coupling portion from a direction intersecting the axial direction of the connecting nut with the nut abutting portion facing the connecting nut threaded onto the male thread portion, and when attached, restricts backward movement of the connecting nut relative to the male thread portion. The locking device can be attached to the joint member and the other coupled portion only when the connecting nut is screwed onto the male threaded portion up to a specified screwing position.

[0013] According to this joint, the coupling members include a coupling portion. The coupling portion and the other coupling portion, and therefore the coupling member and the other coupling portion, are coupled to each other by threading the connecting nut of the coupling portion onto the male thread portion of the other coupling portion. The locking device can be attached to the coupling member and the other coupling portion only when the connecting nut is threaded onto the male thread portion up to a specified threading position. When the locking device is attached to the coupling member and the other coupling portion, the nut abutment portion of the locking device abuts against the rear end face of the connecting nut, opposite the tip of the shank, thereby restricting backward movement of the connecting nut relative to the male thread portion. [Effects of the Invention]

[0014] According to the fluid pipe coupling device and coupling of the present invention, by attaching an anti-loosening device, it is possible to confirm that the connecting nut has been tightened to the required amount, and the anti-loosening device can maintain the required amount of tightening to prevent the connecting nut from loosening. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a perspective view of an embodiment of the present invention; [Figure 2] FIG. [Figure 3] FIG. [Figure 4] 10 is a cross-sectional view showing the process of attaching the locking device to the fluid pipe joint. FIG. [Figure 5] FIG. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] 9 is a cross-sectional view taken along line AA in FIG. 8. [Figure 10] FIG. 10 is a vertical cross-sectional view showing a conventional pipe joint. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0017] 1 to 9 show one embodiment of the present invention. In the drawings, reference numeral 1 denotes a first fluid pipe, 2 denotes a second fluid pipe, 3 denotes a fluid pipe coupling device, and 4 denotes a coupling. Here, the fluid pipe coupling device 3 and the coupling 4 form a fluid flow path and are used, for example, in the drain-up location of an air conditioner, but their uses are not limited to this.

[0018] The fluid pipe coupling device 3 includes a fluid pipe coupling 3a and a locking device 20. The fluid pipe coupling 3a includes a first coupling member 5 and a second coupling member 10 that are coupled to each other. The first coupling member 5 includes a first connection portion 6 to which the first fluid pipe 1 is connected, and a first coupling portion 7 having a first shaft portion 8, and has a fluid flow passage provided therein. The first coupling portion 7 has a connecting nut 9 that is fitted around the outer periphery of the first shaft portion 8 so that it can rotate freely but cannot slip out from the tip side of the first shaft portion 8.

[0019] The second coupling member 10 includes a second connection portion 11 to which the second fluid pipe 2 is connected, and a second coupling portion 12 having a second shaft portion 13, and is provided with a fluid flow passage therein. A male thread portion 13a is formed on the outer periphery of the second shaft portion 13 to be threadedly engaged with a connecting nut 9. Threaded engagement of the connecting nut 9 with the male thread portion 13a connects the first coupling portion 7 and the second coupling portion 12 to each other, and also connects the flow passage of the first fluid pipe 1 to the flow passage of the second fluid pipe 2 via the flow passages of the first and second coupling members 5, 10.

[0020] In the fluid pipe coupling device 3, the locking device 20 has a nut abutting portion 20a that abuts against the rear end face 9a of the connecting nut 9, opposite the tip of the first shaft portion 8, and can be attached to the fluid pipe coupling 3a (more specifically, the first coupling portion 7 and the second coupling portion 12) in a direction 21 intersecting the axial direction of the connecting nut 9 (in the illustrated embodiment, a perpendicular direction) with the nut abutting portion 20a facing the connecting nut 9 that is threaded onto the male thread portion 13a, and when attached, it restricts movement of the connecting nut 9 in a backward direction 22 relative to the male thread portion 13a. The locking device 20 can be attached to the fluid pipe coupling 3a (more specifically, the first coupling portion 7 and the second coupling portion 12) only when the connecting nut 9 has been threaded onto the male thread portion 13a up to a specified engagement position.

[0021] More specifically, the second joint member 10 (more specifically, the second connecting portion 12) has an interlocking portion 12a on the base end side of the male thread portion 13a. Meanwhile, the locking device 20 has an interlocking portion 20b that interlocks with the interlocking portion 12a when attached to the fluid pipe joint 3a, and the interlocking portion 20b and the nut abutment portion 20a restrict movement of the connecting nut 9 in the backward direction 22 relative to the male thread portion 13a.

[0022] The joint 4 includes a joint member 5x (the first joint member 5 described above) and a locking device 20. The joint member 5x includes a connection portion 6x (the first connection portion 6 described above) to which a fluid pipe 1x (the first fluid pipe 1 described above) is connected, and a coupling portion 7x (the first coupling portion 7 described above) having a shaft portion 8x (the first shaft portion 8 described above), and has a fluid flow passage provided therein. The coupling portion 7x has a connecting nut 9 fitted to the outer periphery of the shaft portion 8x so as to be rotatable and unable to slip out from the tip side of the shaft portion 8x. The connecting nut 9 can be threaded onto a male thread portion 13a formed on the outer periphery of another shaft portion 13x (the second shaft portion 13 described above) of another coupling portion 12x (the second coupling portion 12 described above) having a fluid flow passage provided therein.

[0023] In the joint 4, the locking device 20 has a nut abutment portion 20a that abuts against a rear end face 9a of the connecting nut 9, opposite the tip of the shank 8x, and can be attached to the joint member 5x (more specifically, the connecting portion 7x) and another connecting portion 12x in a direction 21 intersecting the axial direction of the connecting nut 9 (in the illustrated embodiment, a perpendicular direction) with the nut abutment portion 20a facing the connecting nut 9 that is threaded onto the male thread portion 13a, and when attached, it restricts movement of the connecting nut 9 in a backward direction 22 relative to the male thread portion 13a. The locking device 20 can be attached to the joint member 5x (more specifically, the connecting portion 7x) and another connecting portion 12x only when the connecting nut 9 has been threaded onto the male thread portion 13a up to a specified engagement position.

[0024] Specifically, the first joint part 5 and the second joint part 10 are both formed with bent axial centers, and by connecting the first joint part 5 and the second joint part 10 at rotational positions rotated relatively around the axial centers of their joining sides, a parallel position (see FIGS. 2 to 4) in which the axial centers of the first connecting part 6 and the second connecting part 11 are parallel, and an orthogonal position (not shown) in which these axial centers are perpendicular to each other are formed.

[0025] The first joint member 5 has a first connection portion 6 composed of a concentric inner tubular portion 6a, an intermediate tubular portion 6b, and an outer tubular portion 6c. The first fluid pipe 1 comprises a pipe main body 1a and a covering member 1b covering the pipe main body 1a. The pipe main body 1a is inserted between the inner tubular portion 6a and the intermediate tubular portion 6b, and the covering member 1b is inserted between the intermediate tubular portion 6b and the outer tubular portion 6c, and they are fixed to the first connection portion 6 by, for example, adhesive. In the first coupling portion 7, a slip-out prevention portion 8a is provided on the outer periphery of the first shank 8 so as to protrude from the outer periphery. Meanwhile, the connecting nut 9 is a cap nut having a protrusion 9b protruding inward from the rear end, opposite the tip of the first shank 8. This protrusion 9b is located further back than the slip-out prevention portion 8a and abuts against the slip-out prevention portion 8a, preventing the connecting nut 9 from slipping out from the tip side of the first shank 8.

[0026] The second joint member 10 has a second connecting portion 11 having a large diameter portion 11a and a small diameter portion 11b so as to accommodate different diameters of the second fluid pipe 2. In the illustrated embodiment, the second fluid pipe 2 has a large diameter, and the second fluid pipe 2 is inserted into the large diameter portion 11a and fixed to this large diameter portion 11a (second connecting portion 11) by, for example, adhesive bonding. In the second coupling portion 12, the aforementioned locked portion 12a is provided so as to protrude from the outer periphery of the second shank 13. The first shank 8 is then inserted into this second shank 13. In the figure, reference numeral 14 denotes a ring-shaped waterproofing member, which is fitted onto the outer periphery of the first shank 8 and comes into close contact with the inner circumferential surface of the second shank 13.

[0027] Locking device 20 has a generally C-shape with a portion of its annular shape missing, which serves as opening 20c for receiving connecting nut 9 and locked portion 12a. Locking device 20 has nut abutting portion 20a and locking portion 20b located at both ends (i.e., both ends in the axial direction of connecting nut 9), with accommodation groove 20d for accommodating connecting nut 9 and locked portion 12a between nut abutting portion 20a and locking portion 20b, so that connecting nut 9 and locked portion 12a are sandwiched between nut abutting portion 20a and locking portion 20b. Therefore, if the connecting nut 9 is not threaded onto the male thread portion 13a to the specified threaded position, the locking device 20 cannot accommodate both the connecting nut 9 and the locked portion 12a, and the locking device 20 cannot be attached to the fluid pipe fitting 3a (more specifically, the first connecting portion 7 and the second connecting portion 12). For this reason, the locking device 20 can be attached to the fluid pipe fitting 3a (more specifically, the first connecting portion 7 and the second connecting portion 12) only when the connecting nut 9 is threaded onto the male thread portion 13a to the specified threaded position.

[0028] Specifically, locking device 20 comprises a band-shaped locking device main body 20e with a portion of the annular shape missing, and the aforementioned nut abutment portion 20a and locking portion 20b that protrude inward from each end of locking device main body 20e in the width direction. When locking device 20 is attached, containing connecting nut 9 and locked portion 12a, it can freely rotate around the outer periphery of connecting nut 9. Furthermore, a finger hook protrusion 20f is provided on the outer periphery of locking device 20 (specifically, locking device main body 20e) near opening 20c.

[0029] Next, the effects of the fluid pipe coupling device 3 and coupling 4 configured as described above will be described. According to the fluid pipe coupling device 3, the fluid pipe coupling 3a includes a first coupling member 5 and a second coupling member 10. The first coupling member 5 includes a first coupling portion 7, and the second coupling member 10 includes a second coupling portion 12. When the connecting nut 9 of the first coupling member 7 is threadedly engaged with the male thread portion 13a of the second coupling member 12, the first coupling portion 7 and the second coupling portion 12, and therefore the first coupling member 5 and the second coupling member 10, are coupled to each other. The anti-loosening device 20 can be attached to the fluid pipe fitting 3a (more specifically, the first connecting portion 7 and the second connecting portion 12) only when the connecting nut 9 has been threaded onto the male thread portion 13a up to the specified threading position, and when the anti-loosening device 20 is attached to the fluid pipe fitting 3a, the nut abutment portion 20a of the anti-loosening device 20 abuts against the rear end face 9a of the connecting nut 9, which is opposite to the tip of the first shaft portion 8, and restricts movement of the connecting nut 9 in the backward direction 22 relative to the male thread portion 13a.

[0030] Furthermore, in the joint 4, the joint part 5x (first joint part 5) has a connecting part 7x (first connecting part 7). The connecting nut 9 of the connecting part 7x is threadedly engaged with the male thread part 13a of the other connecting part 12x (second connecting part 12), thereby connecting the connecting part 7x and the other connecting part 12x, and ultimately the joint part 5x and the other connecting part 12x to each other. The anti-loosening device 20 can be attached to the coupling member 5x (more specifically, the connecting portion 7x) and other connecting portions 12x only when the connecting nut 9 has been threaded onto the male thread portion 13a up to the specified threading position, and when the anti-loosening device 20 is attached to the coupling member 5x and other connecting portions 12x, the nut abutment portion 20a of the anti-loosening device 20 abuts against the rear end face 9a of the connecting nut 9, which is opposite to the tip of the shank portion 8x (first shank portion 8), thereby restricting movement of the connecting nut 9 in the backward direction 22 relative to the male thread portion 13a.

[0031] That is, with these fluid pipe coupling devices 3 and couplings 4, the attachment of the locking device 20 makes it possible to confirm whether the connecting nut 9 has been tightened to the required amount, and the locking device 20 can maintain the required amount of tightening and prevent loosening of the connecting nut 9. In other words, the locking device 20 not only prevents the connecting nut 9 from loosening, but also serves as a checking device for confirming whether the connecting nut 9 has been tightened to the required amount.

[0032] Furthermore, the locking device 20 can freely rotate around the outer periphery of the connecting nut 9 when attached to the fluid pipe coupling 3a (more specifically, the first connecting portion 7 (connecting portion 7x) and the second connecting portion 12 (another connecting portion 12x)). This allows the orientation of the opening 20c to be changed by rotating the locking device 20 after it has been attached. In other words, after the locking device 20 is attached with its opening 20c facing the connecting nut 9, the locking device 20 can be rotated so that the opening 20c faces forward.

[0033] Furthermore, it is preferable that the anti-loosening device 20 be colored in a different color from the fluid pipe coupling 3a, so that it is possible to visually recognize that the anti-loosening device 20 is installed even from a distance.

[0034] The fluid pipe coupling device 3 may also include a heat insulating material (not shown) that covers at least a portion of the fluid pipe coupling 3a together with the locking device 20 when the locking device 20 is attached to the fluid pipe coupling 3a. In this way, after using the locking device 20 to confirm that the amount of engagement between the connecting nut 9 and the male thread portion 13a is appropriate, the locking device 20 can be left attached as a lock when covering with heat insulating material. In other words, there is no need to separately prepare and attach a checking device that confirms the appropriate amount of engagement (i.e., the required amount of tightening of the connecting nut 9) and a locking device that can be covered with heat insulating material.

[0035] The present invention relates to the fluid pipe coupling device 3 and the coupling 4, and the installation method for adding a heat insulating material to these will be described below.

[0036] This is a method for installing a fluid pipe coupling device (3) or a coupling (4), in which the connecting nut (9) is tightened onto the male thread portion (13a) until the locking device (20) can be attached, a third party (a person different from the person who tightened it) checks that the locking device (20) is attached, and then the fluid pipe coupling (3a) or the coupling member (5x) together with the locking device (20) is covered with a heat insulating material.

[0037] The present invention is not limited to the above-described embodiment, and various other modifications are possible. For example, the first joint part 5 and the second joint part 10 are formed with their axis centers bent, but either or both of them may be formed with their axis centers straight, and the shape thereof is not particularly important.

[0038] Furthermore, the coupling portion 7x of the coupling member 5x is coupled to another coupling portion 12x provided on the second coupling member 10, but the other coupling portion 12x is not limited to the second coupling member 10 and may be provided on the appliance, thereby connecting the fluid pipe 1x to the appliance via the coupling member 5x (and ultimately the coupling 4). [Explanation of symbols]

[0039] 1. First fluid pipe 1x fluid tube 2 Second fluid pipe 3 Fluid Coupling Device 3a Fluid pipe fitting 4. Joints 5 First joint member 5x joint parts 6 First connection part 6x connections 7 1st joint 7x joints 8 First shaft 8x shaft 9 Connecting nut 9a End face 10 Second joint member 11 Second connection part 12 Second joint 12x other joints 12a Locked part 13 Second shaft 13x other shafts 13a Male thread 20 Locking device 20a Nut contact part 20b Locking part 20c aperture 20d Receiving groove 21 Crossing Direction 22 Reverse direction

Claims

1. A fluid coupling device comprising a fluid coupling and a locking device, The fluid pipe coupling includes a first coupling member and a second coupling member coupled to each other, the first coupling member includes a first connection portion to which a first fluid pipe is connected and a first coupling portion having a first shaft portion, and a fluid flow passage is provided therein; the first coupling portion has a connecting nut fitted to the outer periphery of the first shaft portion so as to be rotatable and so as not to be slipped out from the tip end side of the first shaft portion, the second coupling member includes a second connection portion to which a second fluid pipe is connected and a second coupling portion having a second shaft portion, and a fluid flow passage is provided therein; a male threaded portion that screws onto the connecting nut is formed on an outer periphery of the second shaft portion, and the first coupling portion and the second coupling portion are coupled to each other by the screwing of the connecting nut and the male threaded portion, and the flow passage of the first fluid pipe and the flow passage of the second fluid pipe are communicated with each other via the flow passages of the first and second coupling members; The locking device has a nut abutment portion that abuts against the rear end face of the connecting nut, which is opposite to the tip of the first shank, and can be attached to the fluid pipe coupling in a direction intersecting the axial direction of the connecting nut with the nut abutment portion facing the connecting nut that is threaded onto the male thread portion, and when attached, restricts movement of the connecting nut in the backward direction relative to the male thread portion, and The anti-loosening device can be attached to the fluid pipe coupling only when the connecting nut is threaded onto the male thread portion up to a specified threaded position, and when attached, can freely rotate around the outer periphery of the connecting nut.

2. the second joint member includes a locked portion on a base end side of the male thread portion, 2. The fluid pipe coupling device according to claim 1, wherein the anti-loosening device has a locking portion that locks onto the locked portion when attached to the fluid pipe coupling, and the locking portion and the nut abutment portion restrict movement of the connecting nut in a backward direction relative to the male thread portion.

3. The locking device is generally C-shaped with a portion of the annulus missing, the missing portion forming an opening for receiving the connecting nut and the locked portion, the nut abutment portion and the locking portion being located at both ends, and the space between the nut abutment portion and the locking portion forming an accommodation groove for accommodating the connecting nut and the locked portion, and 3. The fluid pipe coupling device according to claim 2, wherein the locking device is rotatable around the outer periphery of the connecting nut in an attached state in which the connecting nut and the locked portion are housed therein.

4. 4. The fluid pipe coupling device according to claim 1, further comprising a heat insulating material that covers at least a portion of the fluid pipe coupling together with the locking device when the locking device is attached to the fluid pipe coupling.

5. 4. The fluid pipe coupling device according to claim 1, wherein the locking device is colored differently from the fluid pipe coupling.

6. A joint comprising a joint member and a locking tool, The coupling member includes a connection portion to which a fluid pipe is connected and a coupling portion having a shaft portion, and a fluid flow passage is provided therein; the coupling portion has a connecting nut fitted to the outer periphery of the shaft portion so as to be rotatable and so as not to be able to slip out from the tip end side of the shaft portion, the connecting nut is capable of being threaded onto a male thread portion formed on the outer periphery of another shaft portion of another coupling portion having a fluid flow passage therein; The locking device has a nut abutment portion that abuts against the rear end face of the connecting nut, which is opposite to the tip of the shank, and can be attached to the coupling member and the other coupling portion in a direction intersecting the axial direction of the connecting nut with the nut abutment portion facing the connecting nut that is threaded onto the male thread portion, and when attached, it restricts movement of the connecting nut in the backward direction relative to the male thread portion, and The anti-loosening device can be attached to the coupling member and the other connecting portion only when the connecting nut is threaded onto the male thread portion up to a specified threading position, and when attached, can freely rotate around the outer periphery of the connecting nut.

Images