JP2023152612A - Insert metal fitting for hose connection - Google Patents

Abstract

To prevent external force, which moves a push ring toward a receiving metal fitting side, from being unexpectedly applied to the push ring, while preventing operability of the push ring from deteriorating.SOLUTION: An insert metal fitting 1 for hose connection, which is provided at an end part of a hose H and is used in combination with a receiving metal fitting provided at an end part of another hose, comprises a cylindrical insert metal fitting body 2 having a holding part 21 for holding an end part of the hose H, a push ring 3 provided movably in an axial direction on an outer periphery of the insert metal fitting body 2, and a push ring come-off prevention part 4 that prevents the push ring from coming off toward the holding part 21 side by contacting the push ring. An inner diameter dimension of a cylindrical part 31 of the push ring 3 is set to 101% to 109% with respect to an outer diameter dimension of the insert metal fitting body 2.SELECTED DRAWING: Figure 2

Description

The present invention relates to a hose coupling fitting used for fire hoses and the like.

For example, fire hoses are provided with hose coupling fittings at their ends because it is necessary to quickly connect the hoses at a fire extinguishing scene. This hose coupling fitting has a widely used configuration called the "Machino style", and comprises a pair of a fitting fitting and a receiving fitting. The basic structure of the insert is shown in Patent Document 1. The receiving fitting has a built-in claw portion that is biased radially inward. When the insert is inserted into the receiver, the claw portion of the receiver catches on the step formed at the tip of the insert. As a result, the insert fitting and the receiving fitting are brought into a connected state.

The insert is provided with a push ring that is movable in the axial direction. By moving this push ring in the direction toward the receiving metal fitting, the claw portion of the receiving metal fitting can be pushed up in the radial outward direction and can be made to overcome the step of the insert fitting. Thereby, the insertion fitting and the receiving fitting can be brought into a disconnected state.

In the above-mentioned Machino type fitting, if an external force is applied that causes the push ring to move toward the receiving fitting, the state of engagement between the step and the pawl may suddenly change (for the person handling the hose, such as a firefighter). may be canceled (unintentionally). Examples of causes of the external force include, for example, when handling a fire hose, the fire hose is dragged up the stairs and gets caught on the steps, collides with the edge of a roof, and gets caught on the frame of a building entrance or door. It will be done. On the other hand, in the case of fire hoses, it is desirable to be able to quickly disconnect the hose. For this reason, it is desirable to minimize the decrease in operability when intentionally operating the push ring.

Here, Patent Document 1 describes that the push ring is configured to be tiltable over a large angle range, and with this configuration, when an external force is applied to the push ring, this external force is applied to the push ring. It is said that unintentional disconnection can be prevented because it does not act as a motive force toward the distal end in the axial direction, but is converted into a moment of force against the outer circumference of the proximal end of the insert.

However, the push ring described in Patent Document 1 has a structure in which a step or a tapered surface is formed on the inner peripheral surface. Therefore, the number of machining steps during manufacturing increases. Furthermore, if foreign matter gets mixed in between the press ring and the main body of the insert during use, it will be difficult to remove because it will get caught on the step or tapered surface. In addition, unless the foreign matter is removed, it is difficult to move the push ring, making it difficult to release the coupling. Thus, the joint protector described in Patent Document 1 has room for improvement.

Japanese Patent Application Publication No. 2020-159550

Therefore, the present invention has developed a hose coupling that is unlikely to become uncoupled immediately even if an external force that causes the push ring to move toward the receiving metal fitting side is unexpectedly applied, and that can be uncoupled by intentional operation. The challenge is to provide fittings.

The present invention provides a hose coupling fitting that is provided at the end of a hose and used in combination with a receiving fitting provided at the end of another hose, which has a cylindrical shape and a holding part that holds the end of the hose. A push ring is provided on the outer periphery of the insert body so as to be movable in the axial direction, and a push ring fall-off prevention part that prevents the push ring from coming off toward the holding part by contacting the insert body. The push ring includes a cylindrical portion movable in the axial direction along the outer circumferential surface of the insert main body, and a cylindrical portion extending radially outward from the cylindrical portion to release the connection with the other hose. a flange that is operated by an operator toward the receiving fitting; This is a hose coupling fitting, characterized in that the ratio is set to 101% to 109% based on .

According to this configuration, since the inner diameter dimension of the cylindrical portion is set within the above range, if an external force is applied to the flange portion in a localized area when viewed in the axial direction, such as when the flange is caught on a staircase, etc. , the axis of the cylindrical part changes so that it is inclined with respect to the axis of the insert body. This inclination causes the push ring to get caught and prevent it from moving further toward the receiving fitting. For this reason, the hose coupling fitting and the receiving fitting are unlikely to become uncoupled. On the other hand, as a normal process for uncoupling the insert and the receiving fitting, the entire area of the flange should be in a state where the deviation is small in the axial direction, for example, approximately 180 degrees in the radial direction with respect to the axis of the insert fitting itself. If the push ring is operated by hooking one's fingers on two places, the pushing ring will not get caught, and the coupling can be easily released.

Further, a flange tapered surface may be formed on the holding part side of the flange part so that the radially inner side is located on the holding part side and the radially outer part is located on the receiving metal side. .

According to this configuration, by allowing an object that may apply an external force to the flange to slide against the inclined tapered surface of the flange, all of the external force caused by the object hitting the flange is removed. , it is possible to prevent the push ring from becoming a force that moves it in the axial direction. Furthermore, by converting the direction of at least part of the external force by the flange taper surface, the converted force is changed so that the axis of the cylindrical part is inclined with respect to the axis of the fitting body. It is possible to have a positive effect on what you want to do.

Further, the flange tapered surface may have an inclination angle of more than 0 degrees and less than 25 degrees with respect to a virtual plane perpendicular to the axial direction.

According to this configuration, it is possible to prevent the radially outer side of the collar portion from having a sharp shape, thereby preventing danger.

Further, the push ring removal prevention portion may include a retaining ring that is partially embedded in the insert body.

According to this configuration, even if the push ring has an enlarged inner diameter of the cylindrical part, it can be prevented from slipping out toward the holding part by simply attaching the retaining ring to the insert body.

Further, the retaining ring may have a shape including a main body portion along the insert main body and a convex portion protruding radially outward from the main body portion.

According to this configuration, since the retaining ring can be made to protrude radially outward by the convex part, even if the retaining ring has an enlarged inner diameter dimension of the cylindrical part without increasing the overall shape of the retaining ring, the retaining ring can be It can prevent it from slipping off to the side.

Further, the convex portion may have a curved portion having a radius of curvature different from that of the main body portion of the retaining ring.

According to this configuration, the convex portion can be easily provided on the retaining ring by simply performing a simple bending process.

Further, the convex portion may have a bent portion.

According to this configuration, the convex portion can be easily provided on the retaining ring by simply performing a simple bending process.

Further, the radial cross-sectional shape of the retaining ring may have a radially elongated portion.

According to this configuration, since the radially elongated portion contacts the push ring, even if the push ring has an enlarged inner diameter dimension of the cylindrical portion, it can be prevented from slipping off to the holding portion side.

In the present invention, when an external force is unexpectedly applied, the axis of the cylindrical part is tilted with respect to the axis of the insert body, so that the insert and the receiving bracket are released from the connection. Hateful. Therefore, even if an external force that causes the push ring to move toward the receiving metal fitting side is unexpectedly applied, it is unlikely that the push ring will immediately become uncoupled, and it can be brought to the uncoupled state by an intentional operation.

FIG. 1 is a half-sectional view and an enlarged view of essential parts of a hose coupling fitting according to an embodiment of the present invention. FIG. 3 is a half-sectional view showing the function of the hose coupling fitting. FIG. 3 is a front view showing a retaining ring used in the hose coupling fitting shown in FIGS. 1 and 2. FIG. FIG. 7 is a front view showing a retaining ring according to another embodiment of the present invention. FIG. 7 is a front view showing a retaining ring according to another embodiment of the present invention. FIG. 7 is a half-sectional view showing a hose coupling fitting according to another embodiment of the present invention. FIG. 7 is a half-sectional view showing a hose coupling fitting according to another embodiment of the present invention. FIG. 7 is a sectional view showing a hose coupling fitting according to another embodiment of the present invention. 9 is an enlarged view of the main part of FIG. 8. FIG.

Next, the present invention will be explained by taking up one embodiment. In the hose coupling fitting 1 of this embodiment, the end to which the hose H is attached will be referred to as the proximal end, and the end to be inserted into the receiving fitting will be referred to as the distal end. The direction connecting the proximal end and the distal end is defined as the axial direction. Further, the inner and outer directions with respect to the axis (imaginary axis) of the hose coupling fitting 1 are defined as the radial direction. The direction in which the axis extends is the axial direction.

The hose coupling fitting 1 of this embodiment is provided at the end of a hose H (shown by a chain double-dashed line in FIG. 1) made of a soft material such as a fiber material, and is attached to the end of another hose (not shown). It is used in combination with a receiving metal fitting (not shown) provided in the section. The structure of this combination is called the "Machino style" as mentioned above, and the basic parts of this structure are well known. The hose coupling fitting 1 of this embodiment is characterized in that it has been modified from the above-mentioned "Machino style" structure in that it maintains good operability and is designed to prevent the coupling with the receiving fitting from being unexpectedly released. In the following, the configuration related to the above characteristics will be mainly explained, and conventionally known configurations will be explained to the extent necessary.

As shown in FIG. 1, the hose coupling insert 1 includes an insert main body 2, a push ring 3, and a push ring slip-off prevention portion 4. The fitting main body 2 is a substantially cylindrical portion that holds the end of the hose H. As shown in the figure, the holding portion 21 located in the proximal region of the insert main body 2 has a so-called "bamboo saw" shape with a plurality of steps continuous in the axial direction formed on the outer circumferential surface. After placing the end of the hose H on this holding part 21, the metal cylinder P is placed on the hose H, and by caulking the cylinder P so as to compress it in the radial direction, the hose is connected to the fitting body 2. The end of H can be fixed so that it does not come off. Note that this cylindrical body P is only an example of the structure of a fixture for fixing the hose H to the fitting main body 2, and a ring-shaped or wire-shaped member can also be used as another structure of the fixture. . In addition to caulking, fixing can also be performed by reducing the diameter using winding force, screw force, heat shrinkage, or the like.

The push ring 3 is a portion provided on the outer periphery of the distal end region of the insert main body 2 so as to be movable in the axial direction. This push ring 3 includes a cylindrical portion 31 and a collar portion 32. The cylindrical portion 31 is a cylindrical portion along the outer peripheral surface of the insert main body 2 . The inner diameter of the cylindrical part 31 is set larger than the outer diameter of the part of the insert body 2 where the cylindrical part 31 is arranged, so that the cylindrical part 31 is axially aligned with respect to the insert body 2. It is possible to slide in the direction. Details of the inner diameter of the cylindrical portion 31 will be described later. The outer diameter of the enlarged portion 22 located at the tip of the insert main body 2 is larger than the inner diameter of the cylindrical portion 31. Therefore, the cylindrical portion 31 does not come off from the tip of the insert main body 2.

The collar portion 32 is an annular portion integrally formed at the base end portion of the cylindrical portion 31 so as to extend radially outward from the cylindrical portion 31 . That is, the flange portion 32 is provided so as to extend in the radial direction from the insert main body 2. The flange portion 32 of this embodiment has a flat plate shape, and the proximal end side (radially inner side) and the distal end side (radially outer side) are flat surfaces. The collar portion 32 is operated by an operator (such as a firefighter) toward the receiving fitting in order to release the connection with another hose. When the collar portion 32 is pushed toward the distal end, the cylindrical portion 31 also moves in conjunction. Here, when the hose coupling fitting 1 is connected to the receiving fitting, a claw portion (not shown) of the receiving fitting is placed at a position further toward the proximal end than the step 23 which is the proximal end of the enlarged portion 22. are fitted, and the hose coupling fitting 1 and the receiving fitting cannot be separated. When the collar portion 32 is pushed in the distal direction, the cylindrical portion 31 is inserted into the receiving fitting. The tip portion of the inserted cylindrical portion 31 pushes up the claw portion of the receiving metal fitting in the radially outward direction. Thereby, the claw part is no longer caught on the step 23, and the connection between the hose coupling insert 1 and the receiving metal fitting can be released and the two can be separated.

The push ring slip-off prevention portion 4 is a portion that prevents the push ring 3 from coming off toward the holding portion 21 side (toward the proximal end of the hose coupling insert 1) by abutting against it.

The cylindrical portion 31 of the push ring 3 is formed with a dimension that intentionally causes "backlash" or "wobble" with respect to the insert body 2. Specifically, the inner diameter dimension of the cylindrical part 31 is 101% based on the outer diameter dimension (average value in the range) 2D in the range in which the cylindrical part 31 moves in the axial direction of the fitting main body 2. It is set to 109% to 109%, more preferably 103% to 107%. This setting value means that when the size of the hose coupling fitting 1 is 65A, the axis 31C of the cylindrical part 31 with respect to the axis 2C of the fitting main body 2 is approximately 2 degrees to 10 degrees with the former setting value. The latter setting corresponds to approximately 4 degrees to 8 degrees.

There are three sizes generally used for the hose coupling fitting 1: 65A, 50A, and 40A. The set dimensions of the cylindrical portion 31 can be applied to these three sizes. Incidentally, the preferable range of the inner diameter of the cylindrical portion 31 according to size, as confirmed by the inventor of the present application, is 103.5% to 106% when the size is 65A. Further, in the case of 50A, it is 103.5% to 106%. Further, in the case of 40A, it is 104.6% to 107.1%.

In the pushing ring 3 having the cylindrical part 31 with the inner diameter set in this way, external force is applied to the collar part 32 only in a part of the circumferential direction due to, for example, a collision with a part of a building when routing the hose H. When an external force is applied in the distal direction so as to be localized to a local region in the axial view of the collar portion 32, as in the case where the push ring 3 is applied, the external force acts on the push ring 3 as a moment. Therefore, as shown in Fig. 2, the axis 31C of the cylindrical part 31 changes to be inclined with respect to the axis 2C of the insert body 2 (in Fig. 2, the upper part of the cylindrical part 31 is inclined to the right). ).

Due to the inclination of the axis 31C of the cylindrical portion 31, the push ring 3 is caught in the middle of the range in which the cylindrical portion 31 moves in the axial direction of the insert body 2, and does not move further toward the receiving fitting. For this reason, the hose coupling fitting 1 and the receiving fitting are unlikely to become uncoupled. On the other hand, when the flange portion 32 is operated in a state where the entire region is small (substantially uniform) in the axial direction, the cylindrical portion 31 is By moving the cylindrical portion 31 in the axial direction while the axes 31C of the cylindrical portions coincide with each other or have a small inclination, the pushing ring 3 is not caught, and therefore the coupling release state can be easily achieved. As described above, in the hose coupling fitting 1 of the present embodiment, even if an external force that causes the push ring 3 to move toward the receiving fitting side is unexpectedly applied, it is difficult to immediately release the coupling, and even when the push ring 3 is not operated intentionally. Depending on the situation, it can become uncoupled. In other words, it is possible to achieve both prevention of accidental detachment and operability. Further, the inner circumferential surface of the cylindrical portion 31 of this embodiment can be one continuous curved surface having a constant diameter from the base end side to the distal end side. Therefore, the number of machining steps during manufacturing can be reduced compared to the conventional configuration in which a portion that disrupts the continuity of the surface, such as a step or a tapered surface, is formed on the inner peripheral surface. Further, even if foreign matter gets mixed in between the push ring and the main body of the insert during use, it is easy to remove the foreign matter because there is no part on the inner peripheral surface where the foreign matter can get caught.

The push ring slip-off prevention part 4 has a retaining ring 41 that is partially embedded in the insert body 2. The embedding is performed in a groove formed in the circumferential direction on the outer peripheral surface of the insert main body 2. By simply attaching the retaining ring 41 to the insert body 2, even if the push ring 3 has an enlarged inner diameter of the cylindrical portion 31 as described above, it can be prevented from slipping off to the holding portion 21 side.

The retaining ring 41 can have a shape having a convex portion that partially projects in the radial direction from a main body portion that is attached along the insert main body 2 . In this embodiment, four protrusions 411 are provided in the circumferential direction and are elongated in the radial direction. FIG. 3 shows a front view shape of the retaining ring 41 used in this embodiment. The four protrusions 411 are provided at equal intervals in the circumferential direction. The protrusion 411 is a substantially semicircular protrusion that has a curved portion with a radius of curvature different from that of the main body of the retaining ring 41 . By providing the convex portion (protrusion 411) in this way, a part of the circumferential direction of the retaining ring 41 can be made to protrude radially outward, so that the cylindrical portion 31 can be removed without enlarging the overall shape of the retaining ring 41. Even if the push ring 3 has an enlarged inner diameter, it can be prevented from coming off toward the holding part 21 side. Further, the main body portion of the retaining ring 41 is separated at one location in the circumferential direction, and a slit 412 that widens when attached to the insert body 2 is formed. A slit 413 is also formed at a radially inner position of the protrusion 411 to temporarily expand the diameter of the retaining ring 41 and facilitate the work of embedding it in the insert body 2.

The retaining ring 41 is not limited to the shape shown in FIG. 3, but can have various shapes. For example, the shapes shown in FIGS. 4 and 5 can be used. The retaining ring 41 shown in FIG. 4 has a curved part 414 as the main body part that is fitted into a groove formed in the insert main body 2, and corner parts 415 as the convex parts curved at four places at regular intervals in the circumferential direction. It is provided to protrude from the portion 414 in the radial direction. The corner portion 415 shown in FIG. 4 has a bent portion bent at a substantially right angle. Further, for attachment to the insert main body 2, a slit 416 divided in the circumferential direction is provided. The retaining ring 41 shown in FIG. 5 has the same basic shape as that shown in FIG. 4, but the forming range of the curved part 414 is small, and the degree of protrusion in the radial direction of the corner part 415 is correspondingly large. It is something. Further, although not shown, a curved portion having a larger radius of curvature than the main body portion (curved portion 414) may be provided in place of the corner portion 415. By providing the retaining ring 41 with a corner portion 415 and a curved portion, the retaining ring 41 can be easily provided with a convex portion radially outward by a simple bending process.

By making the retaining ring 41 into these shapes, the radially elongated portion of the cross-sectional shape comes into contact with the push ring 3, so that even if the push ring 3 has an enlarged inner diameter dimension of the cylindrical portion 31, It is possible to prevent it from coming off to the holding part 21 side.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various changes can be made without departing from the gist of the present invention.

For example, in the push ring 3 of the embodiment, the proximal end side of the collar portion 32 is a flat surface as shown in FIG. 1 and the like. However, the present invention is not limited to this, and as shown in FIG. 8 as another embodiment, a flange tapered surface 322 may be provided on the proximal end side (radially inner side) of the flange 32. This alternative embodiment will be described below.

In this other embodiment, on the holding part 21 side of the collar part 32 (the proximal end side in the axial direction of the hose coupling fitting 1), the radially inner side is located on the holding part 21 side, and the radially outer side is located on the receiving fitting side. A flange taper surface 322 is formed so as to be located on the axially distal end side of the hose coupling insert 1. In this embodiment, the flange tapered surface 322 is a surface with a linear cross-sectional shape in the radial direction. However, the radial cross-sectional shape may also be a curved surface (concave or convex). The flange tapered surface 322 is provided all around the push ring 3 in the circumferential direction. Note that it can also be provided intermittently in the circumferential direction.

A flat surface 321 is formed on the radially inner side of the flange tapered surface 322, similar to the embodiment described above. As shown in FIG. 9, the diameter D322 at the starting position 322P of the flange tapered surface 322 is the outer diameter DP of the metal cylinder P that is caulked to fix the hose H to the holding part 21 (more specifically, the caulking process (the maximum dimension) or less. In addition, it is preferable that the diameter dimension D322 of the flange taper surface 322 at the starting position 322P is set to be approximately the same as the outer diameter DP of the cylindrical body P. This is because at a position on the inner diameter side of the cylindrical body P, the possibility that an external object will collide with the position is extremely small because the cylindrical body P becomes an obstacle. Furthermore, if the thickness of the flange 32 and the inclination angle of the flange tapered surface 322 are not changed, and the starting position 322P of the flange tapered surface 322 is closer to the radially inner side, the thickness of the flange 32 cannot be ensured on the radially outer side. This is because the shape may become sharp without being sharp, which may pose a danger to workers such as firefighters. For this reason, both the flat surface 321 and the flange tapered surface 322 are formed.

By forming the flange tapered surface 322 on the flange 32 in this way, objects that may apply external force to the flange 32 can be made to slide against the slanted flange tapered surface 322. , the object can be parried, and therefore the external force caused by the object hitting the flange 32 can be reduced. Furthermore, the direction of at least part of the external force is converted by the flange tapered surface 322 to the normal direction of the flange tapered surface 322 (direction inclined with respect to the axial direction). Since the force is changed so that the axis 31C of the cylindrical portion 31 is inclined with respect to the axis 2C of the insert main body 2 as described in the embodiment, it can be applied positively.

The flange tapered surface 322 has an inclination angle θ of more than 0 degrees and 25 degrees with respect to a virtual plane perpendicular to the axial direction (not shown, but a virtual plane extending in the vertical direction in FIGS. 8 and 9). The following is considered. The inclination angle θ can be preferably set to 5 degrees or more and 20 degrees or less. Although a larger inclination angle is more effective in terms of the above-mentioned effect, the radially outer side of the collar portion 32 becomes sharp, so the angle range is limited to the above range from the viewpoint of preventing danger.

Here, since the inventor of the present application made a prototype of the push ring 3 of this other embodiment and conducted an experiment, it will be briefly described. For 65A diameter: 13 degrees of inclination angle, for 50A diameter: 5 degrees of inclination angle, and for 40A diameter: 10 degrees of inclination angle, we made prototype push rings 3 with a flange tapered surface 322, and these are used for firefighting and rescue operations. It simulates the entrance to enter a building from the outside during activities, and uses a jig made of orthogonal steel materials (for example, H steel or angle material), and attaches fittings and receiving fittings. The jig was connected to the jig, and a hose attached to it was applied to the bent part of the jig as it passed through. As a result, the caliber 65 has a 100% "unexpected detachment prevention effect" that prevents the connection from being released when external force is applied unexpectedly, and the caliber 50A and 40A have almost the same "unexpected detachment prevention effect". It showed "effectiveness". In this way, it was confirmed that the formation of the flange tapered surface 322 was effective within the range of the present experimental conditions. The above is a description of another embodiment.

As a possible modification other than the above-mentioned other embodiment, for example, as shown in FIG. 7, the push ring slip-off prevention part 4 has a protrusion 42 that protrudes radially outward from the insert main body 2 and extends in the circumferential direction. It can also be used as a thing. In this case, a portion of the retaining ring 41 is embedded in this protrusion 42 . By combining the protrusion 42 and the retaining ring 41 in this way, the retaining ring 41 can be made to protrude radially outward by the protrusion 42, so the retaining ring 41 does not need to have a special shape. In this case, the retaining ring 41 may have a circular cross-sectional shape in the radial direction (see the enclosed portion in FIG. 7), and may be a ring with a circumferential portion cut off for fitting.

A tapered surface 421 can be formed on the side of the protrusion 42 that is closer to the push ring 3. Such a tapered surface 421 allows the axis 31C of the cylindrical portion 31 to be aligned with the axis 2C of the insert body 2 when the push ring 3 moves toward the proximal end, thereby eliminating the inclination of the push ring 3. can.

Furthermore, a tapered surface 422 can also be formed on the side of the protrusion 42 opposite to the push ring 3. Due to such a tapered surface 422, when attaching the retaining ring 41 to the protrusion 42 during manufacture of the hose coupling fitting 1, the diameter of the retaining ring 41 is gradually expanded by the tapered surface 422, and the retaining ring 41 is easily guided to the embedded position. can.

Further, the radial cross-sectional shape of the retaining ring 41 does not have to be circular, and may have a shape having a radially elongated portion. For example, as shown in FIG. 6, the flat plate-like body may be ring-shaped and have a constant cross-sectional shape (specifically, a rectangle) in the circumferential direction.

Note that in the above-mentioned protrusion 42, tapered surfaces 421 and 422 were formed on both sides in the axial direction. However, it may also be provided in only one direction in the axial direction.

1 Hose coupling fitting 2 Fitting main body 2C Axial center of fitting main body 2D Outer diameter dimension of fitting main body 21 Holding part 22 Enlarged part 23 Step 3 Push ring 31 Cylindrical part 31C Axis center of cylindrical part 32 Flange part 321 Flat surface 322 Flange tapered surface 4 Push ring slip-off prevention portion 41 Retaining ring 42 Projection H Hose P Clinting body θ Inclination angle of collar tapered surface

Claims (8)

In a hose coupling fitting provided at the end of a hose and used in combination with a receiving fitting provided at the end of another hose,
A cylindrical insert main body having a holding part that holds the end of the hose, a push ring provided on the outer periphery of the insert main body so as to be movable in the axial direction, and the push ring coming off toward the holding part. Equipped with a push ring prevention part that prevents the push ring from coming off by contact,
The push ring includes a cylindrical portion that is movable in the axial direction along the outer circumferential surface of the fitting main body, and a cylindrical portion that extends radially outward from the cylindrical portion and that is configured to disengage the receiving ring for releasing the connection with the other hose. A flange portion that is operated by an operator toward the metal fitting,
The inner diameter of the cylindrical portion is set to 101% to 109% based on the outer diameter of the insert main body in a range in which the cylindrical portion moves in the axial direction. , fitting for hose connection. According to claim 1, a flange taper surface is formed on the holding part side of the flange part so that the radially inner side is located on the holding part side and the radially outer side is located on the receiving metal fitting side. Hose connection fittings listed. The hose coupling fitting according to claim 2, wherein the flange tapered surface has an inclination angle of more than 0 degrees and less than 25 degrees with respect to an imaginary plane perpendicular to the axial direction. The hose coupling fitting according to claim 1, wherein the push ring slip-off prevention portion has a retaining ring that is partially embedded in the fitting main body. The hose coupling insert according to claim 4, wherein the retaining ring has a main body portion that extends along the insert main body, and a convex portion that projects radially outward from the main body portion. The hose coupling insert according to claim 5, wherein the convex portion has a curved portion having a radius of curvature different from that of the main body portion of the retaining ring. The hose coupling fitting according to claim 5, wherein the convex portion has a bent portion. The hose coupling fitting according to claim 4, wherein the retaining ring has a radial cross-sectional shape having a radially elongated portion.