JP7539799B2 - Connecting hardware - Google Patents

Description

The present invention relates to a plug-in type connecting fitting in which the two fittings are connected by inserting the plug into the receiving fitting.

A plug-in type connecting fitting, which is equipped with a male plug fitting and a female receiving fitting, is known as a fitting for connecting fire hoses together (see, for example, Patent Documents 1 to 4). In this connecting fitting, the plug fitting is prevented from coming loose from the receiving fitting by engaging a locking portion, which is a ring-shaped protrusion provided at the tip of the plug fitting, with multiple claws provided on the receiving fitting and biased toward the inside of the fitting.

Each claw can move radially around the axis of the receiving fixture, and is in contact with the outer circumferential surface of the insert when connected. The insert is also fitted with a push ring that can slide along its outer circumferential surface. By pushing each claw up radially with this push ring, the engagement between each claw and the locking portion is released, and the insert can be removed from the receiving fixture.

In actual firefighting activities, when the connecting fitting comes into contact with an obstacle at the scene, the push ring is pushed, and there is a risk that the insert fitting and the receiving fitting will become detached. In regard to this issue, Patent Documents 1 to 4 propose a connecting fitting structure to prevent unintended detachment.

In the fastening hardware disclosed in Patent Document 1, anti-slip grooves are formed on the outer peripheral surface of the insert fitting and the inner peripheral surface of the push ring, and a gap is provided between these outer peripheral and inner peripheral surfaces. As a result, if an uneven force is applied to the push ring by an obstacle, part of the tip of the push ring will lift off the outer peripheral surface of the insert fitting, while the other part will abut against said outer peripheral surface. At this abutting part, the grooves on the outer peripheral surface of the insert fitting and the inner peripheral surface of the push ring engage, restricting the movement of the push ring and preventing the tip of the push ring from reaching the claw.

In the connecting fitting disclosed in Patent Document 2, a protective frame extending in the axial direction is provided around the receiving fitting, and when connected, the protective frame is located closer to the receiving fitting than the flange portion (flange portion) of the push ring (release member). Furthermore, the protective frame is elastic, so that even if an obstacle comes into contact with the pushing ring, the tip of the pushing ring will not reach the claw unless a force sufficient to elastically deform the inner edge of the protective frame and move the flange portion toward the receiving mouth is applied.

In the fastening hardware disclosed in Patent Document 3, an inclined end surface is provided on the flange (peripheral flange) of the push ring (disengagement ring). This allows the two to slide even if an obstacle hits the flange, and the push ring is not pushed in.

In the connecting fitting disclosed in Patent Document 4, a slanted edge is provided on the short tube for attaching the hose to the insert fitting and the receiving fitting. This allows the two to slide even if an obstacle hits the slanted side edge, and the push ring is not pushed in.

JP 2016-14477 A JP 2018-31464 A Japanese Patent Application Publication No. 11-201357 Japanese Patent Application Publication No. 11-287377

Even with the fasteners disclosed in the above Patent Documents 1 to 4, there is still room for improvement in the structure for preventing unintended separation of the receiving fitting and the insert fitting. Therefore, one of the objects of the present invention is to provide an improved fastener that can more effectively prevent unintended separation of the receiving fitting and the insert fitting.

In one embodiment of the connecting fitting, when a plug provided in a spigot is inserted into a receiving fitting provided in a receiving fitting, a locking portion provided on the plug and a claw provided on the receiving fitting engage in an axial direction parallel to the axis of the plug and the receiving fitting, and the engagement between the locking portion and the claw is released by moving the tip of a push ring provided to be slidable in the axial direction relative to the outer circumferential surface of the plug between the claw and the outer circumferential surface and pushing up the claw in a radial direction centered on the axis. The push ring has a cylindrical portion including the tip, a rear end portion located opposite the tip in the axial direction and protruding in the radial direction relative to the cylindrical portion, and a first tapered surface provided at the rear end portion and having an outer diameter increasing as it approaches the tip. The plug has a protrusion that faces the rear end in the axial direction and protrudes radially beyond the cylindrical portion. The protrusion has a second tapered surface whose outer diameter increases as it approaches the rear end.

The maximum outer diameter of the second tapered surface is preferably greater than the minimum outer diameter of the first tapered surface. The maximum outer diameter of the second tapered surface is preferably smaller than the maximum outer diameter of the first tapered surface.

The metal plug may have an attachment portion provided on the outer circumferential surface, and the plug may have a cylindrical fastener that fastens the hose to the attachment portion. In this case, the protrusion may be part of the fastener.

The hose may further include a cylindrical fixture having an attachment portion provided on the outer circumferential surface of the metal plug and a ring inserted between the attachment portion and the fixture from the end of the fixture on the push ring side. In this case, the protrusion may be a part of the ring.

In another embodiment of the fastening fitting, the push ring has a cylindrical portion including the tip end and a rear end portion located on the opposite side of the tip end in the axial direction. Furthermore, the amount of protrusion of the rear end portion relative to the cylindrical portion is 4.8 mm or less.

The metal plug may have an attachment portion provided on the outer circumferential surface, and the plug may have a cylindrical fastener that fastens the hose to the attachment portion. In this case, it is preferable that the amount of protrusion of the rear end from the fastener is 4.5 mm or less.

The metal plug may have an attachment portion provided on the outer circumferential surface, and the plug may be provided with a cylindrical fastener that fastens the hose to the attachment portion. In this case, it is preferable that the outer diameter of the rear end portion is smaller than the outer diameter of the fastener.

In yet another embodiment of the fastening fitting, the push ring has a cylindrical portion including the tip end, and a rear end portion located on the opposite side of the tip end in the axial direction and protruding in the radial direction from the cylindrical portion. Furthermore, the spigot is provided with a flexible cover through which the spigot is passed and which covers the rear end portion.

The metal fitting may have an attachment portion provided on the outer circumferential surface, and the spigot may have a cylindrical fastener for fastening the hose to the attachment portion. In this case, a part of the cover may be located between the fastener and the attachment portion.

In yet another embodiment of the connecting fitting, the push ring has a cylindrical portion including the tip portion, and a rear end portion located on the opposite side of the tip portion in the axial direction and protruding in the radial direction from the cylindrical portion. The insert has a small diameter portion to which the push ring is attached, and a large diameter portion having an outer diameter larger than that of the small diameter portion and having an attachment portion formed on its inner surface for attaching a hose. Furthermore, the outer diameter of the rear end portion is equal to or smaller than the maximum outer diameter of the large diameter portion.

The large diameter portion may have a tapered surface whose outer diameter decreases as it approaches the push ring. In this case, it is preferable that the minimum outer diameter of the tapered surface is smaller than the outer diameter of the rear end portion.

The present invention provides an improved fastener that can more effectively prevent unintended separation of the receiving fastener and the insert fastener.

FIG. 1 is a schematic side view of a fastening fitting according to a first embodiment. FIG. 2 is a view of the socket shown in FIG. 1 as seen from the clamp ring side along the axial direction. FIG. 3 is a partial cross-sectional view of the fastener in a state in which the socket and spigot shown in FIG. 1 are connected. FIG. 4 is a schematic side view of the fitting according to the first embodiment connected to a fire hose. FIG. 5 is an enlarged view of the insertion port M shown in FIG. FIG. 6 is a diagram for explaining the function of the fastening fitting according to the first embodiment. FIG. 7 is a table showing the results of verifying the effectiveness of preventing accidental removal of the fastening fitting according to the first embodiment. FIG. 8 is a schematic side view of a receptacle according to the second embodiment. FIG. 9 is a perspective view showing another example of a shape that can be applied to the push ring according to the second embodiment. FIG. 10 is a perspective view showing still another example of a shape that can be applied to the push ring according to the second embodiment. FIG. 11 is a table showing the results of verifying the effectiveness of the fastening fitting according to the second embodiment in preventing erroneous removal. FIG. 12 is a schematic side view showing another example of the socket according to the second embodiment. FIG. 13 is a schematic side view showing another example of the push ring according to the second embodiment. FIG. 14 is a schematic side view of a socket according to the third embodiment. FIG. 15 is a schematic side view showing another example of the socket according to the third embodiment. FIG. 16 is a schematic side view showing still another example of the socket according to the third embodiment. FIG. 17 is a schematic side view of a receptacle according to the fourth embodiment. FIG. 18 is a schematic perspective view of the cover shown in FIG. FIG. 19 is a partial cross-sectional view of a fastening fitting according to a fifth embodiment.

Several embodiments will now be described with reference to the drawings.
In each embodiment, a plug-in type coupling metal fitting used mainly for connecting fire hoses in the field of firefighting is illustrated as an example, however, the coupling metal fitting can be used for various purposes other than the field of firefighting, such as connecting hoses for industrial and agricultural use.

[First embodiment]
1 is a schematic side view of a coupling fitting C according to a first embodiment. The coupling fitting C includes a socket F and a spigot M. The socket F includes a cylindrical receiving fitting 1 (female fitting) centered on an axis AX1. The spigot M includes a cylindrical insert fitting 2 (male fitting) centered on an axis AX2.

In Figure 1, the receiving bracket 1 and the insert bracket 2 are arranged with the axes AX1 and AX2 aligned. In this state, the direction parallel to the axes AX1 and AX2 is defined as the axial direction Dx. In addition, the direction away from the axes AX1 and AX2 with the axes AX1 and AX2 as the center is defined as the radial direction Dr.

The receiving bracket 1 has a first end 1a and a second end 1b in the axial direction Dx. Furthermore, the receiving bracket 1 has an attachment portion 11 on the outer peripheral surface on the first end 1a side that is inserted into the end of the fire hose, and an enlarged diameter portion 12 on the second end 1b side that has an outer diameter larger than that of the attachment portion 11. The attachment portion 11 has multiple annular steps aligned in the axial direction Dx to prevent the fire hose from slipping out.

The receiving port F further includes an annular clamping ring 3 connected to the enlarged diameter portion 12, and a protective member 4 attached to the outer circumferential surface of the clamping ring 3. The clamping ring 3 is made of a metal material and is connected to the enlarged diameter portion 12, for example, by a number of screws. The protective member 4 is made of a resin material, for example, and its outer circumferential surface protrudes most in the radial direction Dr at the receiving port F and the insertion port M.

The insert 2 has a first end 2a and a second end 2b in the axial direction Dx. Furthermore, the insert 2 has an attachment portion 21 on the outer circumferential surface on the first end 2a side that is inserted into the end of the fire hose, and a locking portion 22 on the second end 2b side. The locking portion 22 is, for example, an annular convex portion that protrudes slightly in the radial direction Dr from the surrounding area. The attachment portion 21 has multiple annular steps formed therein, similar to the attachment portion 11.

The spigot M further includes an annular retaining ring 5 fixed to the outer circumferential surface 2c of the spigot 2 between the mounting portion 21 and the locking portion 22, and a push ring 6 provided between the locking portion 22 and the retaining ring 5 in the axial direction Dx. The retaining ring 5 is, for example, a metal wire attached to an annular groove provided on the outer circumferential surface 2c, and at least a portion of it protrudes in the radial direction Dr beyond the outer circumferential surface 2c.

The push ring 6 has a tip end 6a that faces the locking portion 22, a rear end 6b that is located on the opposite side of the tip end 6a in the axial direction Dx, and a cylindrical portion 60 that includes the tip end 6a. The cylindrical portion 60 surrounds the outer circumferential surface 2c. The locking portion 22 and the retaining ring 5 prevent the push ring 6 from coming off the insert 2. The push ring 6 can slide in the axial direction Dx between the locking portion 22 and the retaining ring 5.

The rear end 6b protrudes in the radial direction Dr from the cylindrical portion 60 over the entire circumference. The rear end 6b having such a shape can also be called a brim or flange portion. Furthermore, the rear end 6b has a tapered surface T1 (first tapered surface) whose outer diameter increases as it approaches the tip end 6a in the axial direction Dx.

Figure 2 is a view of the socket F as seen from the clamp ring 3 side along the axial direction Dx. As shown in the figure, a circumferential direction Dθ is defined centered on the axis AX1 (AX2). Three claws 7A, 7B, 7C are arranged inside the clamp ring 3. The claws 7A, 7B, 7C are arc-shaped along the circumferential direction Dθ and are aligned at equal intervals in the circumferential direction Dθ. Note that the number of claws that the socket F has is not limited to three.

Figure 3 is a partial cross-sectional view of the connecting fitting C in a state where the socket F and the spigot M are connected (connected state). The second end 1b of the receiving fitting 1 protrudes toward the axis AX1 over the entire circumferential direction Dθ. The tightening ring 3 has an end 3a that faces the second end 1b in the axial direction Dx. The end 3a protrudes toward the axis AX1 over the entire circumferential direction Dθ.

The receiving port F further includes a seal material 8 disposed inside the enlarged diameter portion 12, and a claw seat 9 that holds the claws 7A, 7B, and 7C. The seal material 8 is, for example, an annular rubber packing. The claw seat 9 is fixed to the receiving fitting 1 by the clamp ring 3, and is disposed between the second end 1b and the end 3a.

Claw 7A can move parallel to the radial direction Dr between claw base 9 and second end 1b. Claw 7A is biased toward axis AX1 by elastic member 70, which is, for example, a leaf spring. Note that claws 7B and 7C can also move parallel to the radial direction Dr between claw base 9 and second end 1b, like claw 7A, and are biased toward axis AX1 by elastic member 70.

When connecting the socket F and the spigot M, the second end 2b of the spigot 2 is inserted into the enlarged diameter portion 12 of the socket 1 through the opening of the clamp ring 3. At this time, the locking portion 22 pushes the claws 7A, 7B, and 7C upward in the radial direction Dr against the biasing force of the elastic member 70. As a result, the spigot 2 is inserted into the socket 1 up to the position where the second end 2b comes into contact with the inner surface of the enlarged diameter portion 12, as shown in FIG. 3.

When the second end 2b is in contact with the inner surface of the enlarged diameter portion 12, the first flow path 10 formed inside the receiving fitting 1 is connected to the second flow path 20 formed inside the insert fitting 2. At this time, the lip of the sealing material 8 contacts the outer peripheral surface 22a of the locking portion 22, and the gap between the receiving fitting 1 and the insert fitting 2 is kept liquid-tight.

Furthermore, the claws 7A, 7B, and 7C come into contact with the outer circumferential surface 2c of the metal insert 2 due to the biasing force of the elastic member 70. In this state, a portion of each of the claws 7A, 7B, and 7C faces the locking portion 22 in the axial direction Dx. In other words, because the locking portion 22 and the claws 7A, 7B, and 7C engage in the axial direction Dx, the receiving metal insert 1 and the metal insert 2 cannot be separated.

When separating the receiving bracket 1 and the insert bracket 2, the worker pushes the push ring 6 toward the claws 7A, 7B, and 7C. At this time, the tip 6a of the push ring 6 pushes the claws 7A, 7B, and 7C upward in the radial direction Dr, and the engagement between the locking portion 22 and the claws 7A, 7B, and 7C is released.

Figure 4 is a schematic side view of a coupling fitting C connected to a fire hose H. The fire hose H has a jacket woven from a thread material and a lining layer formed on the inside of the jacket.

The receiving port F further includes a cylindrical fastener R1. The spigot M further includes a cylindrical fastener R2. The fastener R1 fastens one end of the fire hose H to the outer circumferential surface of the receiving fitting 1 (the above-mentioned mounting portion 11). The fastener R2 fastens the other end of the fire hose H to the outer circumferential surface of the spigot 2 (the above-mentioned mounting portion 21). The fasteners R1 and R2 are made of a metal such as aluminum or an aluminum alloy.

In the example of FIG. 4, protective cloth G1 is fastened to the outer surface of receiving fitting 1 together with fire hose H by fastener R1. Protective cloth G2 is fastened to the outer surface of insert fitting 2 together with fire hose H by fastener R2. Protective cloth G1 covers the outer surface of fire hose H near receiving port F. Protective cloth G2 covers the outer surface of fire hose H near insert port M.

Such a fire hose H can be connected to another fire hose H by connecting the inlet M to another receiving port F of the other fire hose H, or by connecting the receiving port F to the inlet M of the other fire hose H.

Figure 5 is an enlarged view of the insertion port M shown in Figure 4. In this embodiment, the fixing device R2 has a protrusion PT1 that protrudes in the radial direction Dr beyond the cylindrical portion 60 of the pressing ring 6. The protrusion PT1 faces the rear end portion 6b of the pressing ring 6 in the axial direction Dx.

The protrusion PT1 has a tapered surface T2 (second tapered surface) whose outer diameter increases as it approaches the rear end 6b. For example, the thickness of the fastener R2 is uniform throughout, including the protrusion PT1. In this case, a gap is formed between the inner peripheral surface of the protrusion PT1 and the outer peripheral surface of the insert 2, which becomes larger as it approaches the rear end 6b. A protrusion PT1 of this shape can also be called a flare portion. The protrusion PT1 can be formed, for example, by not narrowing the outer diameter of the end on the rear end 6b side when tightening the fastener R2 to the insert 2.

The width of tapered surface T1 in the axial direction Dx is smaller than the width of tapered surface T2 in the axial direction Dx. Also, the angle of tapered surface T1 relative to the axial direction Dx is larger than the angle of tapered surface T2 relative to the axial direction Dx.

Here, the outer diameter of the cylindrical portion 60 of the pressing ring 6 is defined as φ1, the minimum outer diameter of the tapered surface T1 (the outer diameter at the left end of the tapered surface T1 in the figure) as φ2, the maximum outer diameter of the tapered surface T1 (the outer diameter at the right end of the tapered surface T1 in the figure) as φ3, the outer diameter of the portion of the fixing device R2 other than the protrusion PT1 as φ4, and the maximum outer diameter of the tapered surface T2 (the outer diameter at the right end in the figure) as φ5. Note that the minimum outer diameter of the tapered surface T2 (the outer diameter at the left end of the tapered surface T2 in the figure) is equal to the outer diameter φ4. The centers of the outer diameters φ1 to φ5 are all on the axis AX2.

In the example of FIG. 5, the maximum outer diameter φ5 of tapered surface T2 is larger than the minimum outer diameter φ2 of tapered surface T1 and is smaller than the maximum outer diameter φ3 of tapered surface T1 (φ2<φ5<φ3).

Figure 6 is a diagram for explaining the function of the coupling fitting C according to this embodiment. Here, a socket F and a spigot M connected to separate fire hoses are shown connected and pulled in the direction indicated by the arrow A. The symbol O in the figure represents an obstacle such as a staircase.

Generally, connecting fittings do not have tapered surfaces T1 and T2. In this case, if the connecting fitting hits some kind of obstacle O during firefighting activities using a fire hose connected with the connecting fitting, the rear end of the push ring may be unintentionally pushed, causing the socket and the insertion port to separate. Such separation may lead to serious delays in firefighting activities and even death or injury to firefighters and those in need of rescue.

In contrast, if tapered surfaces T1 and T2 are provided as in the case of the connecting fitting C of this embodiment, even if the connecting fitting C is pulled in the direction indicated by the arrow A, the obstacle O and the tapered surfaces T1 and T2 slide, making it difficult for the push ring 6 to be pressed with a strong force. This prevents the socket F and the insertion socket M from coming apart.

In particular, when the maximum outer diameter φ5 of tapered surface T2 is greater than the minimum outer diameter φ2 of tapered surface T1 as described above, the obstacle O hits tapered surface T1 immediately after the obstacle O and tapered surface T2 slide against each other. Therefore, the push ring 6 is less likely to be pushed than when the obstacle O hits a part of the rear end 6b other than the tapered surface T1, improving the prevention of accidental removal of the connecting fitting C.

Furthermore, as described above, if the maximum outer diameter φ5 of tapered surface T2 is smaller than the maximum outer diameter φ3 of tapered surface T1, the task of releasing the coupling of the coupling fitting C becomes easier. In other words, if the maximum outer diameter φ5 is larger than the maximum outer diameter φ3, the protrusion PT1 gets in the way and makes it difficult for the worker to press the rear end 6b of the push ring 6 with his or her fingers. In contrast, if the maximum outer diameter φ5 is smaller than the maximum outer diameter φ3, it becomes easier to press the rear end 6b, which protrudes beyond the protrusion PT1, with the fingers.

Figure 7 is a table showing the results of verifying the effectiveness of the coupling fitting C of this embodiment in preventing accidental disconnection. For the verification, the inventors prepared sample A1, which is the socket M of a general 65A Machino fitting, and samples A2, A3, and A4 of the socket M of this embodiment, which were produced by improving on the sample A1. A fixing device R2, a protective cloth G2, and a fire hose H were attached to the socket fitting 2 of samples A1, A2, A3, and A4.

Sample A1 does not have tapered surfaces T1, T2, and the outer diameter φ1 of the cylindrical portion 60 of the pressing ring 6 is 70.4 mm, and the outer diameter φ4 of the fixing device R2 is 71 mm. On the other hand, samples A2, A3, and A4 have tapered surfaces T1, T2, and in all cases the outer diameter φ1 of the cylindrical portion 60 of the pressing ring 6 is 70.4 mm, the minimum outer diameter φ2 of the tapered surface T1 is 73 mm, and the outer diameter φ4 of the fixing device R2 excluding the protruding portion PT1 is 71 mm. Note that it is more difficult to increase the precision of the outer diameter φ4 compared to the other outer diameters, and it can vary in the range of 71 to 72 mm.

Samples A2, A3, and A4 differ in the maximum outer diameter φ3 of tapered surface T1 and the maximum outer diameter φ5 of tapered surface T2. That is, in sample A2, the maximum outer diameter φ3 is 90 mm and the maximum outer diameter φ5 is 76 mm, in sample A3, the maximum outer diameter φ3 is 86 mm and the maximum outer diameter φ5 is 76 mm, and in sample A4, the maximum outer diameter φ3 is 84 mm and the maximum outer diameter φ5 is 78 mm.

For the verification, a socket F was connected to the socket M of each sample A1, A2, A3, and A4, and the socket M and socket F were hung from an obstacle O (a staircase in this case) with a corner as shown in Figure 6, and the fire hose H of the socket M was pulled horizontally without applying excessive force. This operation was performed 10 times for each of samples A1, A2, A3, and A4, and a record was made of whether the push ring 6 got caught on the obstacle O. The results are entered in the "Number of tests" column in Figure 7, with a circle indicating that the push ring 6 did not get caught and a cross indicating that it did get caught.

For sample A1, snagging occurred 9 times out of 10 times. On the other hand, for samples A2, A3, and A4, no snagging occurred. This demonstrates that providing tapered surfaces T1 and T2 as in this embodiment reduces snagging of the push ring 6, thereby contributing to preventing accidental removal.

[Second embodiment]
In the second embodiment, another structural example that can be applied to the fastening fitting C from the viewpoint of preventing erroneous removal will be disclosed. Configurations that are not specifically mentioned can be similar to those in the first embodiment.

Figure 8 is a schematic side view of the spigot M of the fastener C according to the second embodiment. This spigot M does not have the tapered surfaces T1, T2 and the protruding portion PT1 described above. Furthermore, the rear end 6b of the push ring 6 has a smaller diameter than the example shown in Figure 5.

Here, in this embodiment, the outer diameter (maximum outer diameter) of the rear end 6b is defined as φ6, the amount of protrusion of the rear end 6b from the cylindrical portion 60 (=(φ6-φ1)/2) is defined as d1, and the amount of protrusion of the rear end 6b from the fixing device R2 (=(φ6-φ4)/2) is defined as d2.

In order to prevent accidental detachment of the connecting fitting C due to the push ring 6 hitting an obstacle, it is preferable that the protrusion amounts d1 and d2 are small. As will be described in detail later, a good effect of preventing accidental detachment can be obtained if the protrusion amount d1 is 4.8 mm or less, or if the protrusion amount d2 is 4.5 mm or less.

Figures 9 and 10 are perspective views showing other examples of shapes that can be applied to the push ring 6. In the example of Figure 9, a tapered surface T1 is provided around the entire circumference of the rear end 6b. In the example of Figure 10, a pair of tapered surfaces T1a, T1b are provided on the rear end 6b, and flat surfaces S1a, S1b are provided between these tapered surfaces T1a, T1b. The flat surfaces S1a, S1b are, for example, surfaces with a shallower inclination in the radial direction Dr than the tapered surfaces T1a, T1b, and in one example, are planes parallel to the radial direction Dr.

If a tapered surface T1 is provided as in the example of FIG. 9, the two will slide even if the rear end 6b hits an obstacle, as in the first embodiment. Therefore, in combination with the effect of reducing the protrusion amounts d1 and d2 of the rear end 6b, accidental removal is more easily prevented.

On the other hand, if the protrusion amounts d1 and d2 of the rear end 6b are reduced and a tapered surface T1 is provided, it becomes difficult to press the rear end 6b with a finger. In contrast, with the shape shown in FIG. 10, the flat surfaces S1a and S1b can be pressed with a finger to easily release the connecting fitting C. Note that the push ring 6 according to the first embodiment may be provided with similar flat surfaces S1a and S1b.

Figure 11 is a table showing the results of verifying the effectiveness of the coupling fitting C according to the second embodiment in preventing accidental disconnection. For the verification, the inventors prepared sample A1 (same as sample A1 in Figure 7), which is a common 65A Machino fitting socket M, and samples B1, B2, B3, and B4 of the socket M according to this embodiment, which were improved from sample A1. A fixing device R2, a protective cloth G2, and a fire hose H were attached to the socket fitting 2 of samples A1, B1, B2, B3, and B4.

In all of samples A1, B1, B2, B3, and B4, the outer diameter φ1 of the cylindrical portion 60 is 70.4 mm, and the outer diameter φ4 of the fixing device R2 is 71 mm. Note that the outer diameter φ4 can vary in the range of 71 to 72 mm.

In sample A1, the outer diameter φ6 of the rear end 6b is 90 mm, the protrusion amount d1 of the rear end 6b relative to the cylindrical portion 60 is 9.8 mm, and the protrusion amount d2 of the rear end 6b relative to the fixing device R2 is 9.5 mm. In sample B1, the outer diameter φ6 is 80 mm, the protrusion amount d1 is 4.8 mm, and the protrusion amount d2 is 4.5 mm. In sample B2, the outer diameter φ6 is 78 mm, the protrusion amount d1 is 3.8 mm, and the protrusion amount d2 is 3.5 mm. In sample B3, the outer diameter φ6 is 76 mm, the protrusion amount d1 is 2.8 mm, and the protrusion amount d2 is 2.5 mm.

Samples A1, B1, B2, B3, and B4 do not have a tapered surface T1, but sample B4 has a tapered surface T1 as shown in Figure 9. In sample B4, the outer diameter φ6 (maximum outer diameter φ3 of tapered surface T1) is 80 mm, the protrusion amount d1 is 4.8 mm, and the protrusion amount d2 is 4.5 mm, just like sample B1.

The verification was performed 10 times for each of samples A1, B1, B2, B3, and B4 using the same method as described in the first embodiment. The results are entered in the "Number of tests" column in Figure 11, with a circle indicating that the push ring 6 did not get caught and a cross indicating that it did get caught.

As for sample A1, as mentioned above, snagging occurred 9 times out of 10 times. On the other hand, in sample B1, snagging occurred only 4 times out of 10 times. Also, in sample B2, which has smaller protrusion amounts d1 and d2 than sample B1, snagging occurred only once out of 10 times, and in sample B3, which has even smaller protrusion amounts d1 and d2, no snagging occurred. Based on this verification, it can be seen that by reducing the protrusion amounts d1 and d2, snagging of the push ring 6 is suppressed, which ultimately contributes to preventing accidental removal.

Since the frequency of snagging was reduced to less than half of the number of tests at least in sample B1, it is preferable that the protrusion amount d1 is 4.8 mm or less or the protrusion amount d2 is 4.5 mm or less, as described above. Furthermore, since no snagging occurred in sample B3, it is even more preferable that the protrusion amount d1 is 2.8 mm or less or the protrusion amount d2 is 2.5 mm or less. From the viewpoint of facilitating the operation of pressing the push ring 6 with a finger, it is preferable that the protrusion amount d2 is 2.0 mm or more, and even more preferable that it is 3.0 mm or more.

Although sample B4 had the same protrusion amounts d1 and d2 as sample B1, it did not get caught even once. This shows that the effect of preventing accidental removal is further improved by reducing the protrusion amounts d1 and d2 and providing tapered surface T1.

Figure 12 is a schematic side view showing another example of the insertion port M according to this embodiment. In the example shown in this figure, the outer diameter φ4 of the fixing device R2 is larger than the outer diameter φ6 of the rear end 6b (φ4>φ6). In other words, the protrusion amount d2 is negative. In this configuration, it becomes difficult for an obstacle to hit the rear end 6b. Note that the same effect can be obtained even when the outer diameter φ4 is equal to the outer diameter φ6 (when the protrusion amount d2 is zero).

Figure 13 is a schematic side view showing another example of the push ring 6 according to this embodiment. In the example shown in this figure, the rear end 6b does not protrude from the cylindrical portion 60. In other words, the outer diameter φ6 of the rear end 6b matches the outer diameter φ1 of the cylindrical portion 60, and the protrusion amount d1 is zero. Even with this configuration, the push ring 6 is less likely to be pushed by an obstacle.

As described above, the coupling fitting C disclosed in this embodiment also contributes to reducing the size of the fire hose during storage. That is, a fire hose with a socket F connected to one end and a spigot M connected to the other end is usually stored in a state where it is wound around the spigot M, or in a state where the hose is folded at a position about halfway through its overall length and wound around this folded part, with the spigot M and the socket F positioned on the outside of the wound hose. In this case, if the outer diameter φ6 of the rear end 6b is large, the size of the wound fire hose also becomes large. On the other hand, if the outer diameter φ6 is small as in this embodiment, the size of the wound fire hose can be reduced. This allows the fire hose to be stored in a compact bundle.

[Third embodiment]
In the first embodiment, the fixing device R2 is provided with the protrusion PT1. In the third embodiment, a fastener C is disclosed that includes another protrusion that plays a similar role to the protrusion PT1. Configurations that are not specifically mentioned may be the same as those in the above-described embodiments.

Figure 14 is a schematic side view of the socket M of the coupling fitting C according to the third embodiment. In the example shown in this figure, the socket M includes a ring 100. The fixing device R2 does not have a protrusion PT1.

The ring 100 has a cylindrical base 101 and a protruding portion PT2 provided at one end of the base 101. The protruding portion PT2 protrudes in the radial direction Dr beyond the base 101 and the cylindrical portion 60. The base 101 is inserted between the mounting portion 21 (see FIG. 1) and the fixing device R2 from the end of the fixing device R2 on the push ring 6 side. The base 101 is fastened to the metal fitting 2 by the fixing device R2. The base 101 may be located between the fixing device R2 and the protective cloth G2, or may be located between the protective cloth G2 and the fire hose inside it.

The protrusion PT2 is located between the fixing device R2 and the rear end 6b in the axial direction Dx, and faces the rear end 6b. Furthermore, the protrusion PT2 has a tapered surface T3 (second tapered surface) whose outer diameter increases as it approaches the rear end 6b. For example, the inner diameter of the ring 100 is constant throughout in the axial direction Dx. In this case, the thickness of the ring 100 increases at the position of the protrusion PT2. The ring 100 can be formed of, for example, rubber or synthetic resin.

The relationship between the maximum outer diameter of the tapered surface T3 and the outer shape φ1 of the cylindrical portion 60, and the minimum outer diameter φ2 and maximum outer diameter φ3 of the tapered surface T1 is similar to the relationship between the maximum outer diameter φ5 of the tapered surface T2 in the first embodiment and each of the outer diameters φ1 to φ3.

Figure 15 is a schematic side view showing another example of the insertion port M. In the example shown in this figure, the protrusion PT2 further has a tapered surface T4. The tapered surface T4 is a surface located on the opposite side of the tapered surface T4 in the axial direction Dx, and faces the rear end 6b. The tapered surface T4 has a shape in which the outer diameter increases with increasing distance from the rear end 6b. With such a tapered surface T4, when an obstacle hits the protrusion PT2 from the push ring 6 side, the obstacle and the tapered surface T4 slide against each other. This makes it difficult for the protrusion PT2 to get caught on the obstacle.

Figure 16 is a schematic side view showing yet another example of the spigot M. In the example shown in this figure, the rear end 6b has a smaller diameter than that shown in Figure 14. The amount of protrusion d1 of the rear end 6b from the cylindrical portion 60 is preferably 4.8 mm or less, as described in the second embodiment. In addition, the various outer diameter relationships described in the second embodiment can be applied to the push ring 6 and the fixing device R2.

In the example of FIG. 16, the rear end 6b does not have a tapered surface T1. However, the rear end 6b may have a tapered surface T1.

Even when the ring 100 has a protruding portion PT2 and a tapered surface T3 as in this embodiment, the same effect as in the first embodiment can be obtained.

[Fourth embodiment]
In the fourth embodiment, from the viewpoint of preventing erroneous removal, another structural example that can be applied to the fastening fitting C will be disclosed. Configurations that are not specifically mentioned can be similar to those of the above-mentioned embodiments.

Figure 17 is a schematic side view of the spigot M of the connecting fitting C according to the fourth embodiment. In the example shown in this figure, the spigot M is provided with a flexible cover 200. The cover 200 has a first end 200a on the push ring 6 side and a second end 200b located on the opposite side of the first end 200a in the axial direction Dx. Furthermore, the cover 200 has a first portion 201 on the first end 200a side and a second portion 202 on the second end 200b side. The cover 200 can be formed, for example, from rubber or cloth material with excellent elasticity.

The first part 201 covers the rear end 6b of the push ring 6. The second part 202 is inserted between the mounting part 21 (see FIG. 1) and the fastener R2 from the end of the fastener R2 on the push ring 6 side, and is fastened to the metal fitting 2 by the fastener R2. The second part 202 may be located between the fastener R2 and the protective cloth G2, or between the protective cloth G2 and the fire hose inside it.

Figure 18 is a schematic perspective view of the cover 200. For example, the first part 201 has a larger inner diameter and outer diameter than the second part 202. However, the first part 201 and the second part 202 may have the same inner diameter and outer diameter.

The first part 201 has a circular first opening 203 at the first end 200a. The second part 202 has a circular second opening 204 at the second end 200b. The cover 200 has the metal insert 2 and the push ring 6 passing through these openings 203 and 204.

In the example of FIG. 18, an annular frame portion 205 is provided around the first opening 203. Furthermore, the inner diameter of the first opening 203 is smaller than the outer diameter of the rear end portion 6b of the push ring 6. The frame portion 205 is harder than, for example, other parts of the cover 200, and hooks onto the rear end portion 6b of the push ring 6. The frame portion 205 may be formed of the same material as the other parts of the cover 200.

When such a cover 200 is attached, a part of the cover 200 forms an inclined surface between the rear end 6b and the fixing device R2. This makes it difficult for an obstacle to hit the rear end 6b. Even if an obstacle hits the rear end 6b from above the cover 200, the obstacle and the surface of the cover 200 slide, making it difficult for the push ring 6 to be pushed. As a result, the receiving port F and the insertion port M are prevented from accidentally coming loose.

In addition, because the cover 200 is elastic, if an operator presses the rear end 6b from above the cover 200 with his/her finger, the push ring 6 can be pushed to the disconnection position while the rear end 6b remains covered by the cover 200.

Such a cover 200 may be applied to a fitting C having a rear end 6b with a small outer diameter, as disclosed in the second embodiment, for example. The cover 200 may also be applied to the fitting C disclosed in the first or third embodiment.

[Fifth embodiment]
In the first to fourth embodiments, a coupling fitting C is disclosed in which a fire hose or protective cloth is attached to the outer peripheral surfaces of the receiving fitting 1 and the insert fitting 2. In the fifth embodiment, a coupling fitting C is disclosed in which a fire hose or protective cloth is attached to the inner peripheral surfaces of the receiving fitting 1 and the insert fitting 2. Configurations that are not specifically mentioned can be similar to those of the above-mentioned embodiments.

Figure 19 is a partial cross-sectional view of a connecting fitting C according to the fifth embodiment. In this connecting fitting C, an attachment portion 11 is formed on the inner circumferential surface of the receiving fitting 1 in the area on the first end 1a side, and an attachment portion 21 is formed on the inner circumferential surface of the insert fitting 2 in the area on the first end 2a side.

When attaching a fire hose and protective cloth to the receiving fitting 1, the fire hose and protective cloth are inserted inside the receiving fitting 1, and a cylindrical fastener is inserted further inside that. In this state, the fastener is expanded in diameter, thereby tightening the fire hose and protective cloth to the mounting part 11. Similarly, when attaching a fire hose and protective cloth to the insert fitting 2, the fire hose and protective cloth are inserted inside the insert fitting 2, and a cylindrical fastener is inserted further inside that. In this state, the fastener is expanded in diameter, thereby tightening the fire hose and protective cloth to the mounting part 21.

The insert 2 has a small diameter portion 23 and a large diameter portion 24 whose outer diameter and inner diameter are larger than those of the small diameter portion 23. The small diameter portion 23 is located on the second end 2b side, and the large diameter portion 24 is located on the first end 2a side. The push ring 6 is attached to the outer peripheral surface of the small diameter portion 23. The attachment portion 21 is formed on the inner peripheral surface of the large diameter portion 24.

The locking portion 22 is a separate member from the insert 2 and is attached to the second end 2b. The large diameter portion 24 and the locking portion 22 prevent the push ring 6 from coming off, so the insert M does not have the above-mentioned retaining ring 5.

In the example of FIG. 19, a tapered surface T4 is formed at the end of the large diameter portion 24 on the push ring 6 side. The tapered surface T4 has a shape in which the outer diameter increases as it moves away from the rear end portion 6b.

Here, the outer diameter of the rear end 6b is defined as φ7, the outer diameter (maximum outer diameter) of the large diameter portion 24 as φ8, and the minimum outer diameter of the tapered surface T4 (the outer diameter of the right end of the tapered surface T4 in the figure) as φ9. In this embodiment, the outer diameter φ7 is equal to or less than the outer diameter φ8 (φ7≦φ8). In the example of FIG. 19, the outer diameter φ7 is smaller than the outer diameter φ8 (φ7<φ8). If the outer diameter φ7 is equal to or less than the outer diameter φ8, the rear end 6b is protected by the large diameter portion 24, making it difficult for obstacles to hit the rear end 6b. This can prevent the socket F and the insertion socket M from accidentally coming loose.

It is preferable that the minimum outer diameter φ9 of the tapered surface T4 is smaller than the outer diameter φ7 (φ7>φ9). In this case, it is easier to press the rear end 6b with a finger when releasing the connection between the receiving port F and the insertion port M.

The rear end 6b may have the tapered surface T1 shown in Figures 3 and 9, or the tapered surfaces T1a, T1b and flat surfaces S1a, S1b shown in Figure 10.

The first to fifth embodiments described above do not limit the scope of the present invention to the configurations disclosed in those embodiments. In addition, various structures can be applied to the fasteners depending on the application. The configurations disclosed in each embodiment can be combined as appropriate.

The fire hose and protective cloth can also be attached by wrapping a wire around them and fastening them to the outer periphery of the receiving bracket 1 and the insert 2. In this case, the wrapped wire corresponds to the fastener in each of the above-mentioned embodiments. For example, the outer diameter of the rear end 6b of the push ring 6 may be smaller than the outer diameter of the wrapped wire. Also, the ring 100 shown in Figures 14 to 16 and the cover 200 shown in Figure 17 may be attached to the insert 2 by the wire.

5 may be further provided for the fastener R1 of the socket F. Also, the ring 100 shown in FIGS.
The claims as originally filed in this application are set forth below.
[1]
A fastening device in which, by inserting a plug provided in a plug mouth into a receiving fitting provided in a receiving mouth, a locking portion provided on the plug mouth and a claw provided on the receiving fitting engage in an axial direction parallel to the axes of the plug mouth and the receiving fitting, and the engagement between the locking portion and the claw is released by moving a tip of a push ring provided on an outer peripheral surface of the plug mouth so as to be slidable in the axial direction between the claw and the outer peripheral surface and pushing up the claw in a radial direction centered on the axis,
The push ring is
A cylindrical portion including the tip portion;
a rear end portion located opposite the tip end portion in the axial direction and protruding in the radial direction relative to the cylindrical portion;
a first tapered surface provided at the rear end portion, the first tapered surface having an outer diameter increasing toward the front end portion;
having
the insertion port includes a protrusion that faces the rear end portion in the axial direction and protrudes in the radial direction beyond the cylindrical portion,
The protruding portion has a second tapered surface whose outer diameter increases toward the rear end portion.
Connecting fittings.
[2]
The maximum outer diameter of the second tapered surface is greater than the minimum outer diameter of the first tapered surface.
The connecting fitting described in [1] above.
[3]
The maximum outer diameter of the second tapered surface is smaller than the maximum outer diameter of the first tapered surface.
The connecting fitting described in [2] above.
[4]
The insert has a mounting portion provided on an outer circumferential surface,
The spigot includes a cylindrical fastener for fastening the hose to the mounting portion,
The protrusion is a part of the fixing device.
A fastener described in any one of [1] to [3] above.
[5]
The insert has an attachment portion provided on an outer circumferential surface,
The said insertion port is
A cylindrical fastener for fastening the hose to the mounting portion;
A ring is inserted between the mounting portion and the fixture from an end of the fixture on the push ring side;
Further equipped with
The protrusion is a part of the ring.
A fastener described in any one of [1] to [3] above.
[6]
A fastening device in which, by inserting a plug provided in a plug mouth into a receiving fitting provided in a receiving mouth, a locking portion provided on the plug mouth and a claw provided on the receiving fitting engage in an axial direction parallel to the axes of the plug mouth and the receiving fitting, and the engagement between the locking portion and the claw is released by moving a tip of a push ring provided on an outer peripheral surface of the plug mouth so as to be slidable in the axial direction between the claw and the outer peripheral surface and pushing up the claw in a radial direction centered on the axis,
The push ring is
A cylindrical portion including the tip portion;
a rear end portion located opposite the front end portion in the axial direction;
having
The amount of protrusion of the rear end portion relative to the cylindrical portion is 4.8 mm or less.
Connecting fittings.
[7]
The insert has an attachment portion provided on an outer circumferential surface,
The spigot includes a cylindrical fastener for fastening the hose to the mounting portion,
The amount of protrusion of the rear end portion from the fixing device is 4.5 mm or less.
The connecting fitting described in [6] above.
[8]
The insert has an attachment portion provided on an outer circumferential surface,
The spigot includes a cylindrical fastener for fastening the hose to the mounting portion,
The outer diameter of the rear end is smaller than the outer diameter of the fastener.
The connecting fitting described in [6] above.
[9]
A fastening device in which, by inserting a plug provided in a plug mouth into a receiving fitting provided in a receiving mouth, a locking portion provided on the plug mouth and a claw provided on the receiving fitting engage in an axial direction parallel to the axes of the plug mouth and the receiving fitting, and the engagement between the locking portion and the claw is released by moving a tip of a push ring provided on an outer peripheral surface of the plug mouth so as to be slidable in the axial direction between the claw and the outer peripheral surface and pushing up the claw in a radial direction centered on the axis,
The push ring is
A cylindrical portion including the tip portion;
a rear end portion located opposite the tip end portion in the axial direction and protruding in the radial direction relative to the cylindrical portion;
having
The plug has a flexible cover through which the plug is passed and which covers the rear end.
Connecting fittings.
[10]
The insert has a mounting portion provided on an outer circumferential surface,
The spigot includes a cylindrical fastener for fastening the hose to the mounting portion,
A portion of the cover is positioned between the fixing device and the mounting portion.
The connecting fitting described in [9] above.
[11]
A fastening device in which, by inserting a plug provided in a plug mouth into a receiving fitting provided in a receiving mouth, a locking portion provided on the plug mouth and a claw provided on the receiving fitting engage in an axial direction parallel to the axes of the plug mouth and the receiving fitting, and the engagement between the locking portion and the claw is released by moving a tip of a push ring provided on an outer peripheral surface of the plug mouth so as to be slidable in the axial direction between the claw and the outer peripheral surface and pushing up the claw in a radial direction centered on the axis,
The push ring is
A cylindrical portion including the tip portion;
a rear end portion located opposite the tip end portion in the axial direction and protruding in the radial direction relative to the cylindrical portion;
having
The said fitting is
A small diameter portion to which the push ring is attached;
a large diameter portion having an outer diameter larger than that of the small diameter portion and having an attachment portion formed on an inner circumferential surface thereof for attaching a hose;
having
The outer diameter of the rear end portion is equal to or smaller than the maximum outer diameter of the large diameter portion.
Connecting fittings.
[12]
The large diameter portion has a tapered surface whose outer diameter decreases as it approaches the press ring,
The minimum outer diameter of the tapered surface is smaller than the outer diameter of the rear end portion.
The fastener described in [11] above.

C...connecting fitting, F...receptacle, M...insertion port, R1, R2...fixture, 1...receptacle, 2...insertion fitting, 6...pressure ring, 6a...tip, 6b...rear end, 60...cylindrical portion, PT1, PT2...projection, T1-T4...tapered surface, 100...ring, 200...cover.

Claims (3)

A fastening device in which, by inserting a plug provided in a plug mouth into a receiving fitting provided in a receiving mouth, a locking portion provided on the plug mouth and a claw provided on the receiving fitting engage in an axial direction parallel to the axes of the plug mouth and the receiving fitting, and the engagement between the locking portion and the claw is released by moving a tip of a push ring provided on an outer peripheral surface of the plug mouth so as to be slidable in the axial direction between the claw and the outer peripheral surface and pushing up the claw in a radial direction centered on the axis,
The push ring is
A cylindrical portion including the tip portion;
a rear end portion located opposite the tip end portion in the axial direction and protruding in the radial direction relative to the cylindrical portion;
a first tapered surface provided at the rear end portion, the first tapered surface having an outer diameter increasing toward the front end portion;
having
The insert has an attachment portion provided on an outer circumferential surface,
The said insertion port is
A cylindrical fastener for fastening the hose to the mounting portion;
A ring is inserted between the mounting portion and the fixture from an end of the fixture on the push ring side;
Further equipped with
the ring includes a protrusion that faces the rear end portion in the axial direction and protrudes in the radial direction beyond the cylindrical portion,
The protruding portion has a second tapered surface whose outer diameter increases toward the rear end portion.
Connecting fittings. The maximum outer diameter of the second tapered surface is greater than the minimum outer diameter of the first tapered surface.
The fitting according to claim 1. The maximum outer diameter of the second tapered surface is smaller than the maximum outer diameter of the first tapered surface.
The fitting according to claim 2.

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