CN105637274B - Pipe fitting - Google Patents

Abstract

Provided is a pipe joint capable of suppressing stress concentration occurring at corners of an outer flange formed on a core material and ensuring strength in the axial direction of the outer flange. By forming a concave arc-shaped first inclined surface (52) at the corner formed by the outer peripheral surface of the resin core (14) and the outer flange (50), it is possible to suppress the effect of crossing the axial direction. Stress concentration occurs on the corner when an external force in the direction of . A second inclined surface (64) abutting against the first inclined surface (52) is provided on the inner flange (60) of the metal cap nut (54), and when the cap nut (54) is tightened, the The second side wall surface (61) of the inner flange (60) is in contact with the first side wall surface (51) of the outer flange (50), and the second inclined surface (64) is in contact with the first side wall surface (51) of the core material (14). The inclined surfaces (52) are in contact. The contact area between the inner flange (60) and the outer flange (50) can be increased, and the axial strength of the outer flange (50) can be ensured.

Description

Fitting

technical field

The invention relates to a pipe joint.

Background technique

A pipe joint is used to connect a pipe to a screw joint of a machine or the like. As such a pipe joint, there is a union joint (Japanese: Union 継手) (for example, refer to Patent Document 1). The union joint is configured to include a cylindrical core material connected to a threaded joint, and an ark nut for fixing the core material to the threaded joint.

The union joint tightens the union nut to the external thread of the threaded joint, so that the inner flange of the cap nut pushes the outer flange of the core material to the side of the threaded joint, and the outer flange is clamped and fixed to the inner flange and the inner flange. between threaded joints.

A side wall surface perpendicular to the axial direction is provided on the inner flange side of the outer flange, and a side wall surface opposite to the side wall surface of the outer flange is provided on the outer flange side of the inner flange. When the cap nut is tightened, the outer The side wall surface of the flange receives a pressing force from the side wall surface of the inner flange.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2005-114001

Contents of the invention

The problem to be solved by the invention

However, since the outer flange of the union joint is clamped and fixed between the inner flange of the cap nut and the threaded joint, when an external force in a direction crossing the axial direction acts on the core material, stress concentrates on the outer flange. corner. When the core material is a synthetic resin, it is preferable to suppress stress concentration as much as possible in consideration of durability.

In order to suppress this stress concentration, it is generally considered to form an arcuate surface at the corner of the outer flange. However, when the arc surface is enlarged in consideration of stress concentration, the side wall surface of the outer flange that receives the pressing force from the inner flange tends to be smaller, and the contact area between the inner flange and the outer flange becomes smaller. On the other hand, since the pushing force is concentrated on a part of the outer flange, the strength in the axial direction of the outer flange is reduced.

In order to ensure the contact area between the inner flange and the outer flange, it is also considered to increase the size of the outer flange and the cap nut, but the size of the joint increases and the cost also increases. In addition, when the diameter of the core material is reduced in order to ensure the contact area between the inner flange and the outer flange, the inner diameter of the core material decreases, resulting in a decrease in flow rate.

In consideration of the above facts, an object of the present invention is to provide a structure capable of securing the axial direction of the outer flange even when an inclined surface for suppressing stress concentration is formed at the corner of the outer flange formed on the core material. Strong pipe joints.

solutions to problems

The pipe joint according to the first aspect includes: a core material made of synthetic resin and formed in a cylindrical shape, and a pipe body is connected to one end in the longitudinal direction; an outer flange is annular and formed on the core material. the other end of the outer flange and extends radially outward; the abutment surface is formed on the outer flange and includes a first inclined surface, the first inclined surface is provided between the core material and the outer flange The corner portion between and inclined relative to the outer peripheral surface of the core material when viewed in a section along the axial direction; and the cap nut including: a cylindrical portion formed with an internal thread portion; an internal flange formed from The end of the cylindrical portion protrudes radially inward and has a hole through which the core material passes; The corner portion of the flange is a second inclined surface abutting against the first inclined surface.

In the pipe joint according to the first aspect, for example, an annular sealing member is arranged between the threaded joint and the outer flange formed on the core material, and the internal thread portion of the cap nut is screwed into the external thread portion of the threaded joint, and fastened. The pipe body is connected to the external thread portion of the threaded joint at the connecting portion provided on the core material, so that the pipe body and the threaded joint can be connected to each other.

In addition, since the abutment surface including the first inclined surface provided at the corner of the outer flange is formed on the outer flange of the joint main body, the inner flange of the cap nut is provided with the first inclined surface with the outer flange. The second inclined surface abutting against the first inclined surface is also the abutted surface abutting against the abutting surface of the outer flange, so the contact area of the inner flange and the outer flange can be increased when the cap nut is tightened . Therefore, the strength of the core material in the direction perpendicular to the axial direction is secured while suppressing stress concentration at the corners of the outer flange, and the strength in the axial direction of the outer flange can be secured.

In addition, the inclined surface mentioned here includes not only a linear inclined surface inclined at a constant angle, but also a curved inclined surface whose inclination angle gradually changes.

According to a second technical solution, in the pipe joint according to the first technical solution, the radial dimension h of the first inclined surface is relative to the distance along the radial direction from the outer peripheral surface of the core material to the outer peripheral surface of the outer flange. The radial dimension H of the outer flange is set to be 40% or more.

In the pipe joint according to the second aspect, since the radial dimension h of the first inclined surface is relative to the radial dimension H of the outer flange along the radial direction from the outer peripheral surface of the core material to the outer peripheral surface of the outer flange, Since it is set at 40% or more, it is possible to effectively suppress stress concentration when an external force in a direction intersecting the axial direction acts on the core material.

The third technical solution In the pipe joint of the first technical solution or the second technical solution, the first inclined surface is a concave arc surface with a radius of curvature r1, and the second inclined surface is a convex circle with a radius of curvature r2 Arc surface, and set as r1=r2.

In the pipe joint of the third technical solution, since the first inclined surface is set as a concave arc surface with a radius of curvature r1, the second inclined surface is set as a convex arc surface with a radius of curvature r2, and is set as r1 = r2, therefore, the first inclined surface formed as a concave arc surface and the second inclined surface formed as a convex arc surface can be reliably brought into contact over the entire surface.

According to a fourth technical solution, in the pipe joint according to any one of the first technical solution to the third technical solution, the abutting surface has a first side wall surface perpendicular to the outer peripheral surface of the core material, and the The contact surface has a second side wall surface that contacts the first side wall surface.

In the pipe joint according to the fourth aspect, the abutting surface includes a first side wall surface perpendicular to the outer peripheral surface of the core material and a first inclined surface formed as a concave arc surface, and the abutted surface includes a first side wall surface perpendicular to the first side wall surface. The abutting second side wall surface and the second inclined surface abutting against the first inclined surface.

Therefore, the first inclined surface can be brought into contact with the second inclined surface, and the first side wall surface can be brought into contact with the second side wall surface.

The effect of the invention

As described above, according to the pipe joint of the present invention, even when the corner portion of the outer flange formed on the core material is formed with an inclined surface for suppressing stress concentration, the axial direction of the outer flange can be ensured. Strength of.

Description of drawings

FIG. 1 is a cross-sectional view along an axis, showing a pipe joint according to an embodiment of the present invention.

2A is an enlarged cross-sectional view along the axis, showing a state where the inner flange of the cap nut is in contact with the outer flange of the core material.

2B is an enlarged cross-sectional view along the axis, showing a state where the inner flange of the cap nut is separated from the outer flange of the core material.

Fig. 3 is a cross-sectional view along the axis showing a state where a resin pipe and a screw joint are connected to the pipe joint according to the embodiment of the present invention.

Fig. 4 is a cross-sectional view along the axis, showing the abutting surface and the abutted surface of the pipe joint according to the second embodiment.

Fig. 5 is a cross-sectional view along the axis, showing the abutting surface and the abutted surface of the pipe joint according to the third embodiment.

Detailed ways

[the first embodiment]

A pipe joint 10 according to a first embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1 , the pipe joint 10 of this embodiment is configured to include a joint main body 12 and a cap nut 54 .

(joint body)

The joint main body 12 includes a core material 14 , a sleeve 16 , an intermediate ring 18 , a disengagement member 20 , a lock ring 24 , and an O-ring 22 as a leak preventing member, and these members are arranged so that their central axes coincide with each other. In addition, in this embodiment, the core material 14, the sleeve 16, the intermediate ring 18, and the disengagement member 20 are molded articles of synthetic resin.

The arrow L direction side of the core material 14 is formed as a core portion 26 that can be inserted into the resin tube P to be connected. A pair of fitting grooves 28 are formed on the outer peripheral surface of the core portion 26 , and O-rings 22 are respectively fitted into these fitting grooves 28 . When the core portion 26 is inserted into the resin tube P, the O-ring 22 comes into close contact with the inner peripheral surface of the resin tube P, and seals between the resin tube P and the core material 14 .

The arrow R direction side of the core material 14 is formed as a large-diameter portion 30 having a larger diameter than the core portion 26 , and a groove 32 is formed in the large-diameter portion 30 near the boundary with the core portion 26 .

The intermediate ring 18 is disposed outside the outer peripheral surface of the core material 14 on the side in the arrow L direction.

The end portion of the intermediate ring 18 on the arrow R direction side enters the groove 32 of the core material 14 and fits into the groove 32 of the core material 14 , whereby the intermediate ring 18 is fixed to the core material 14 .

The hollow cylindrical insertion portion 34 surrounded by the inner peripheral surface of the intermediate ring 18, the outer peripheral surface of the core portion 26, and the end of the large-diameter portion 30 is set to have a predetermined size in which the end portion of the resin pipe P can be inserted.

On the outer peripheral surface of the intermediate ring 18 on the side in the arrow R direction, a sleeve engaging portion 36 formed in a concave-convex shape is formed.

The sleeve 16 is formed in a substantially cylindrical shape, and is arranged outside the outer peripheral surface of the intermediate ring 18 on the side in the arrow L direction.

On the inner peripheral surface of the sleeve 16, a concave-convex engaged portion 38 capable of fitting with the sleeve engaging portion 36 is formed on the arrow L direction side. The sleeve engaging portion 36 is fitted into the engaged portion 38 to fix the intermediate ring 18 to the sleeve 16 .

On the side of the engaged portion 38 of the sleeve 16 in the direction of the arrow L, there are sequentially formed an inclined portion 40 whose inner diameter decreases as it goes in the direction of the arrow L, a first constant diameter portion 42 with a constant inner diameter, and a first constant diameter portion with a first inner diameter ratio. The constant diameter portion 42 has a second constant diameter portion 44 having a small inner diameter.

The lock ring 24 is disposed on the inner peripheral side of the inclined portion 40 of the sleeve 16 and is located between the intermediate ring 18 and the disengagement member 20 described later. The lock ring 24 has a plurality of elastically deformable claws 24A protruding inward at intervals in the circumferential direction, and the diameter of an imaginary circle passing through the tip ends of the claws 24A is set to be slightly smaller than the resin pipe P. the outer diameter.

The disengagement member 20 is formed in a substantially cylindrical shape with an inner diameter slightly larger than the outer diameter of the resin tube P, and is disposed on the inner peripheral side of the sleeve 16 so as to be movable along the central axis K1. The disengagement member 20 includes a pressing inclined portion 46 for pressing the claw portion 24A toward the arrow R direction side, and a constant outer diameter portion 48 located on the arrow L direction side of the pressing inclined portion 46 .

In order to prevent the engagement release member 20 from falling off the sleeve 16, the constant outer diameter portion 48 of the engagement release member 20 is formed to have an outer diameter smaller than the inner diameter of the first constant diameter portion 42 of the sleeve 16, and an outer diameter larger than the second constant diameter portion 42. The inner diameter of the diameter portion 44 .

As shown in FIGS. 1 , 2A and 2B , an annular outer flange 50 extending radially outward is formed at an end portion of the large-diameter portion 30 of the core material 14 in the arrow R direction.

As shown in FIG. 2B , a first inclined surface 52 is formed at a corner (the base of the outer flange 50 ) formed by the outer peripheral surface of the large diameter portion 30 and the first side wall surface 51 of the outer flange 50 .

The first side wall surface 51 of the present embodiment is perpendicular to the axis of the core material 14 when viewed in cross-section along the axial direction of the core material 14 . The first inclined surface 52 has a concave arc shape with a radius of r1 having a center of curvature on the radially outer side of the large-diameter portion 30 when viewed in a cross-section along the axial direction of the core material 14, and is smoothly connected to the large-diameter portion 30. The outer peripheral surface of the portion 30 and the first side wall surface 51.

In addition, the first side wall surface 51 and the first inclined surface 52 of the present embodiment correspond to the contact surface of the present invention.

(cap nut)

As shown in FIGS. 1 , 2A and 2B , the cap nut 54 is formed of a hexagonal column-shaped metal member. A first hole 56 is formed axially from the end on the arrow R side toward the arrow L direction, and a second hole 58 having an inner diameter smaller than that of the first hole 56 is formed on the arrow L side of the first hole 56 . In the first hole 56 , a female screw 62 is formed from the end on the arrow R direction side toward the bottom of the hole.

The inner diameter of the first hole 56 is set to a size capable of inserting the outer flange 50 of the core material 14 . On the other hand, the inner diameter of the second hole 58 is set to be smaller than the outer diameter of the outer flange 50 of the core material 14 and slightly larger than the outer diameter of the large-diameter portion 30 of the core material 14 . Thereby, the cap nut 54 is relatively rotatable with respect to the core material 14, and can move freely in the axial direction.

An annular inner flange 60 extending radially inward from the inner surface of the first hole 56 is formed between the end portion of the cap nut 54 on the arrow L direction side and the bottom of the first hole 56 .

The second side wall surface 61 on the side of the first hole 56 (in the direction of arrow R) of the inner flange 60 is perpendicular to the axis of the cap nut 54 when viewed in a section along the axial direction of the cap nut 54, The first side wall surface 51 of the edge 50 faces and can be in contact with the first side wall surface 51 .

In addition, a second inclined surface 64 facing the first inclined surface 52 formed on the core material 14 of the joint main body 12 is formed at an inner corner of the inner flange 60 on the first hole 56 side (arrow R direction side). The second inclined surface 64 has a convex arc shape having a center of curvature on the radially inner side of the inner flange 60 and having a radius r2 when viewed in a cross section along the axial direction. In the present embodiment, the radius r1 of the first inclined surface 52 and the radius r2 of the second inclined surface 64 are set to have the same size.

In addition, the second side wall surface 61 and the second inclined surface 64 of the present embodiment correspond to the contacted surface of the present invention.

Thus, the second side wall surface 61 of the inner flange 60 can be brought into contact with the first side wall surface 51 of the outer flange 50 , and the second inclined surface 64 of the inner flange 60 can be brought into contact with the first side wall surface of the outer flange 50 . The inclined surfaces 52 are in contact with each other.

(Effect)

Next, a method of using the pipe joint 10 of this embodiment will be described.

First, a connection procedure between the pipe joint 10 and the threaded joint 66 as one connection target will be described.

As shown in FIG. 1 , an annular seal 68 is arranged between the outer flange 50 of the core material 14 of the pipe joint 10 and the threaded joint 66 , and the inner thread 62 of the cap nut 54 is screwed to the outer surface of the threaded joint 66 . Thread 70 and tighten cap nut 54.

By tightening the cap nut 54 , the pipe joint 10 is connected to the threaded joint 66 , as shown in FIGS. 2A and 2B , the outer flange 50 and the seal 68 are clamped between the inner flange 60 and the threaded joint 66 .

Thus, the second side wall surface 61 of the inner flange 60 abuts against the first side wall surface 51 of the outer flange 50 , and the second inclined surface 64 of the inner flange 60 abuts against the first inclined surface 52 of the outer flange 50 . catch.

In the pipe joint 10 of this embodiment, the arc-shaped first inclined surface 52 is formed at the corner formed by the outer peripheral surface of the large-diameter portion 30 and the first side wall surface 51 of the outer flange 50, so that the When a force in a direction intersecting the axial direction acts on the core material 14, stress concentration occurs at the above-mentioned corners.

The force in the direction intersecting the axial direction refers to, for example, an external force when a wrench for fastening the cap nut 54 of another adjacent pipe joint 10 hits, but it may also be an external force when the resin pipe P is pulled. Other external forces such as external forces acting at the same time.

In addition, in order to effectively suppress the above-mentioned stress concentration, as shown in FIG. When H is the dimension and h is the radial dimension of the first inclined surface 52 measured along the radial direction, h is preferably 40% or more of H.

In addition, in the pipe joint 10 of this embodiment, since the second inclined surface 64 of the inner flange 60 is brought into contact with the first inclined surface 52 of the outer flange 50, and the second side wall surface 61 of the inner flange 60 Since it is in contact with the first side wall surface 51 of the outer flange 50, the contact area between the outer flange 50 and the inner flange 60 can be increased.

Therefore, although the first inclined surface 52 is formed at the corner of the outer flange 50, when the cap nut 54 is fastened, the entire side portion of the inner flange side of the outer flange 50 can receive the friction of the inner flange 60. Since the pressing force does not concentrate on a part of the outer flange 50, the strength in the axial direction of the outer flange can be ensured.

In the pipe joint 10 of this embodiment, since the first inclined surface 52 and the second inclined surface 64 are formed in a simple arc shape, it is easy to form the first inclined surface 52 and the second inclined surface 64, and the first inclined surface The dimensional stability of the 52 and the second inclined surface 64 is also good, and the first inclined surface 52 and the second inclined surface 64 can be reliably brought into contact.

Finally, a connection procedure between the pipe joint 10 and the resin pipe P to be connected on the other side will be described.

The resin tube P is inserted into the insertion portion 34 of the joint main body 12 , and the end of the resin tube P is brought into contact with the end of the large-diameter portion 30 . By inserting the resin tube P into the insertion portion 34, the claw portion 24A of the lock ring 24 expands under the action of the resin tube P, and the tip end of the claw portion 24A is caught on the outer peripheral surface of the resin tube P, thereby preventing the resin tube P from being opened. The resin pipe P is connected to the pipe joint 10 reliably. In addition, when the resin pipe P is connected to the joint body 12 , the O-ring 22 of the core material 14 is in close contact with the inner peripheral surface of the resin pipe P, thereby ensuring the sealing between the resin pipe P and the core material 14 .

[the second embodiment]

Next, a pipe joint 10 according to a second embodiment of the present invention will be described with reference to FIG. 4 . In addition, the same code|symbol is attached|subjected to the same structure as 1st Embodiment, and description is abbreviate|omitted.

In the first embodiment, the first inclined surface 52 has a concave arc shape with a center of curvature and a radius r1 on the radially outer side of the large diameter portion 30, but the present invention is not limited thereto, and may be as shown in FIG. As shown, the linear inclined surface is inclined at a constant angle with respect to the outer peripheral surface of the large-diameter portion 30 and the first side wall surface 51 . In this case, the second inclined surface 64 of the cap nut 54 has a shape capable of contacting the first inclined surface 52 .

[the third embodiment]

Next, a pipe joint 10 according to a third embodiment of the present invention will be described with reference to FIG. 5 . In addition, the same code|symbol is attached|subjected to the same structure as 1st Embodiment, and description is abbreviate|omitted.

As shown in FIG. 5 , the first inclined surface 52 may be configured to include an arcuate surface 52A and a linear inclined surface 52B inclined at a constant angle. In this case as well, the second inclined surface 64 of the cap nut 54 has a shape capable of contacting the first inclined surface 52 including the arcuate surface 52A and the inclined surface 52B.

In addition, although not shown, the first inclined surface 52 may be a curved shape formed by connecting a plurality of concave arc shapes with different radii of curvature, or may be a plurality of linear inclined surfaces with different inclination angles (respectively: constant angle) connected faces.

(Other implementations)

As mentioned above, embodiment of this invention was given and described, but these embodiment is an example, and various changes can be implemented in the range which does not deviate from the summary of this invention. In addition, of course, the scope of protection of the present invention is not limited to these embodiments.

In the above-mentioned embodiment, the first side wall surface 51 and the first inclined surface 52 are formed on the inner flange side of the outer flange 50 of the core material 14, but the present invention is not limited thereto, and the outer flange 50 may be The inner flange side does not have the first side wall surface 51 perpendicular to the axial direction, and the entire inner flange side becomes the first inclined surface 52 . In this case, the inner flange 60 of the cap nut 54 has the entire outer flange side as the second inclined surface 64 .

In the above-mentioned embodiment, the radius r1 of the first inclined surface 52 is made to coincide with the radius r2 of the second inclined surface 64. However, due to manufacturing errors and the like, the radius r1 and the radius r2 may not completely coincide.

Explanation of reference signs

10 pipe joint; 12 joint body; 14 core material; 16 sleeve (connection); 18 intermediate ring (connection); 22 O-shaped sealing ring (connection); 24 locking ring (connection); 26 core (connection part); 50 outer flange; 51 first side wall surface (contact surface); 52 first inclined surface (contact surface); 54 cap nut; 56 first hole; 58 second hole; 60 inner flange; 61 second side wall surface (contacted surface); 62 internal thread; 64 second inclined surface (contacted surface).

Claims (3)

1. a kind of pipe fitting, wherein, which includes：

Core, it is synthetic resin system and is formed as cylindric, and sets the core for tube body connection in length direction one end, And the diameter large-diameter portion bigger than the diameter of the core is set in length direction the other end；

Outward flange, it is ring-type and is formed at the large-diameter portion, and is radially oriented outside extension；

Bearing surface, it is formed at the outward flange, and including the 1st inclined plane, the 1st inclined plane be arranged on the core with it is described outer Corner between flange and the outer circumferential surface inclination under section axially during observation relative to the core；And

Acorn nut, it includes：Canister portion, it is formed with internal thread part；Inward flange, it is radially oriented interior from the end of cartridge Side is prominent and with for the perforative hole of the core；And by bearing surface, it is abutted against with the bearing surface, this is by abutting bread The corner for being formed at the inward flange and the 2nd inclined plane abutted against with the 1st inclined plane are included,

1st inclined plane is the concaved circular cambered surface that radius of curvature is r1, and the 2nd inclined plane is the dome arc that radius of curvature is r2 Face, and it is set as r1=r2,

The radius of curvature is that the center of curvature of the concaved circular cambered surface of r1 is located at the radial outside of the large-diameter portion, the radius of curvature It is located at the inside of the inward flange for the center of curvature of the convex arc surface of r2.

2. pipe fitting according to claim 1, wherein,

The radial dimension h of 1st inclined plane relative to from the outer circumferential surface of the core untill the outer circumferential surface of the outward flange The radial dimension H of the outward flange along radial direction be set to more than 40%.

3. pipe fitting according to claim 1 or 2, wherein,

The bearing surface has 1st side wall orthogonal with the outer circumferential surface of the core,

It is described that there is the 2nd side wall abutted against with the 1st side wall by bearing surface.