JP7191363B2 - pipe joint - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint used for connecting pipes of different thicknesses.

Conventionally, in this type of pipe joint, after the pipe is inserted into the nipple, a tightening member is placed on the outer side of the pipe and rotated in the inserting direction of the pipe, so that the nipple and the tightening member (pressing portion) are moved. In some cases, a tubular body is sandwiched (tightened) and connected so that it cannot be pulled out (see, for example, Patent Document 1).
A locking member provided across the nipple into which the tubular body is inserted and the tightening member at the final tightening position prevents the tightening member from rotating relative to the nipple, so that the tightening member is loosened in the removal direction of the tubular body. I am stopping.
As the tubular body, a pipe made of hard material or a hose or tube made of soft material is used.

WO2018/020898

By the way, we have prepared many types of pipes with different inner and outer diameters depending on the piping location of the pipe and the flow rate of the fluid passing through the pipe. There are many types of inserts with different sizes.
Furthermore, in order to satisfy demands such as pressure resistance and heat resistance required for the tubular body, there are cases where a plurality of types of tubular bodies having different wall thickness dimensions are prepared. In other words, it is necessary to connect a plurality of types of pipe bodies having different outer diameter sizes due to differences in wall thickness even if the inner diameter size of the pipe body is the same for nipples of the same size.
In this way, a pipe with a thick wall and a large outer diameter (large diameter) is inserted into a nipple of the same size and sandwiched by a tightening member (pressing part), and a thin pipe with a small outer diameter (small diameter) is inserted. When the body is inserted and sandwiched by the tightening members, the final tightening position (tightening completion position) of the tightening member with respect to the nipple is different due to the difference in wall thickness of the tubular body.
That is, when a thin tubular body inserted into a nipple is sandwiched (tightened) by the pressing portion of the tightening member, the tightening member is pushed in the inserting direction of the tubular body until the pressing portion is pressed against the small-diameter outer surface of the thin tubular body. Rotational movement becomes possible.
On the other hand, when a thick tubular body inserted into a nipple is sandwiched (tightened) by the pressing portion of the tightening member, the gap between the large-diameter outer surface of the thick tubular body and the pressing portion becomes narrow. , the pressing portion presses at a relatively faster timing than when tightening a thin tubular body. Therefore, the final tightening position (tightening completion position) of the tightening member with respect to the nipple becomes impossible to rotate when tightening a thick tubular body before tightening a thin tubular body.
Furthermore, when multiple types of tubular bodies with different wall thicknesses are hard pipes, the outer surface of the pipe is hardly compressed and deformed even if the operator rotates the tightening member to press the pressing portion against the outer surface of the pipe. , There was a clear difference in the final tightening position (tightening completion position) of the tightening member to the nipple due to the difference in wall thickness of the pipe.
As a result, if the locking member provided over the nipple into which the pipe is inserted and the tightening member is set to match the thin pipe, the anti-loosening function will not be exhibited in the case of the thick pipe. On the other hand, if the anti-loosening function is set according to the thickness of the tubular body, the anti-loosening function will not be exhibited in the case of the thin tubular body.
In order to demonstrate the anti-loosening function for multiple types of pipe bodies with different wall thicknesses, it is necessary to prepare nipples and tightening members dedicated to each size, which only increases the number of parts and complicates management. However, there is a problem of increased cost.

In order to solve such problems, a pipe joint according to the present invention includes a nipple provided along an insertion space of a plurality of types of tubular bodies having different wall thicknesses, and the plurality of types of pipes inserted along the nipple. It has a pressing part which is provided to be relatively rotatable in the axial direction and the circumferential direction with respect to the body, and which presses the plurality of types of tubular bodies against the outer peripheral surface of the nipple as it rotates relative to the nipple. a tightening member; and a locking member that locks the tightening member so that it cannot rotate with respect to the nipple by engagement between an engaging protrusion and an engaging recess provided over the nipple and the tightening member, One of the engaging convex portion and the engaging concave portion is arranged at a plurality of tightening completion positions corresponding to the plurality of types of tubular bodies accompanying rotational movement of the tightening member with respect to the nipple, and the engaging convex portion or the engaging concave portion The other of the engaging recesses is disposed so as to face one of the engaging protrusions or the engaging recesses in the radial direction and to engage with the engaging protrusions in the circumferential direction, and the engaging protrusions or the engaging recesses that determine the tightening completion position. One of the engaging recesses includes a first portion arranged over all of the plurality of tightening completion positions and a second portion arranged only at a subsequent tightening completion position among the plurality of tightening completion positions. characterized by having

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the whole structure of the pipe joint which concerns on embodiment of this invention, (a) is a partially notched front view when the wall thickness of a pipe body is thick, (b) is (1B) of Fig.1 (a). )-(1B) A longitudinal side view along the line, (c) is a partially cutaway front view when the thickness of the tubular body is thin, (d) is the (1D)-(1D) line in FIG. 1(c) It is a vertical cross-sectional side view along. It is a perspective view before connection. It is the expansion perspective view which looked at the clamping member from the opposite direction.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail based on the drawings.
A pipe joint A according to an embodiment of the present invention, as shown in FIGS. It is a fluid coupling used for
More specifically, a pipe joint A according to an embodiment of the present invention includes a joint body 10 having a nipple 11 provided along an insertion space S of a plurality of types of tubular bodies B, and a plurality of types of nipples 11 inserted along the nipple 11. A tightening member 20 provided to be rotatably movable relative to the tubular body B in the axial direction and the circumferential direction, and a lock for preventing loosening of the tightening member 20 provided over the nipple 11 side and the tightening member 20 side and a member 30 as main components.
An insertion space S for a plurality of types of tubular bodies B is formed between the nipple 11 of the joint body 10 and the tightening member 20 .
Note that the axial direction in which the tightening member 20 rotates means the inserting direction of the plurality of types of tubular bodies B and the opposite removal direction thereof. The direction of removal opposite to the pipe insertion direction N is hereinafter referred to as "pipe removal direction U". The direction in which the operator rotates the tightening member 20 is hereinafter referred to as "tightening direction F". The loose rotation direction of the tightening member 20 opposite to the tightening direction F is hereinafter referred to as "loosening direction L".

The plurality of types of tubular bodies B are pipes, hoses, tubes, or the like having different inner diameters and outer diameters due to differences in wall thickness.
In the illustrated example, there are only two types of tubular bodies B, ie, a thick tubular body Ba with a large outer diameter and a thin tubular body Bb with a small outer diameter. The inner diameters of the thick tubular body Ba having a large outer diameter and the thin tubular body Bb having a small outer diameter are set to the same size.
When the plural types of tubular bodies B are pipes, they are made of hard materials such as hard synthetic resins and metals, and are configured in a single-layer structure or a multi-layer structure.
In particular, in the case of pipes having different inner diameters, it is preferable to have an enlarged diameter end portion Bc that is inserted along the outer peripheral surface 11a of the nipple 11, which will be described later. The diameter-enlarged end portion Bc is a portion forcibly expanded in diameter and deformed by inserting a special tool into the end portion (end opening) of the pipe on the connecting side before insertion. The diameter-enlarged end portion Bc is preferably formed in a tapered shape that gradually expands in diameter toward the end portion of the pipe.
Even if the inner diameters of the pipes are different from each other, by integrally forming the enlarged diameter end portion Bc at the end of the pipe, the inner diameter of the enlarged diameter end portion Bc is enlarged and deformed to the set size. The enlarged diameter end portion Bc can be easily inserted into a nipple 11 (described later) formed at . At the same time, the inner diameter of substantially the entire pipe excluding the enlarged diameter end portion Bc becomes equal to the inner diameter of the nipple 11, which will be described later.
1(a) to 1(d) and FIG. 2 as specific examples of a plurality of types of tubular bodies B are single-layered pipes, but metal layers, hard resin layers, etc. are integrally laminated. It is also possible to replace it with a multi-layered pipe.
In addition, although not shown in the figure when multiple types of tubular bodies B are multi-layered pipes, a core layer made of aluminum, an aluminum alloy, or a lightweight metal similar to aluminum, and polyethylene, crosslinked polyethylene, or similar to polyethylene It is preferable to have an inner layer made of a soft synthetic resin or the like. Furthermore, it is more preferable to use a pipe having a five-layer structure in which an outer layer made of the same material as the inner layer is added to the core layer and the inner layer, and an adhesive layer is sandwiched between the respective layers.

The joint body 10 is made of a hard synthetic resin such as super engineering plastic (super engineering plastic) having excellent heat resistance, chemical resistance, and impact resistance, or a hard material such as rust-resistant metal such as stainless steel or brass, and has a substantially cylindrical shape. formed in
The joint main body 10 has a nipple 11 and a guide portion 12 provided radially facing an inner surface of a tightening member 20 described later.
The nipple 11 is formed in a cylindrical shape with an outer diameter that is approximately the same as or slightly smaller than the inner diameter of the enlarged diameter end portions Bc of the tubular bodies B of the plurality of types.
It is preferable to provide a seal member 11b on the outer peripheral surface 11a of the nipple 11, which is in pressure contact with the inner surface B1 of a plurality of types of tubular body B (diameter-enlarged end portion Bc). The seal member 11 b is an annular body made of an elastically deformable material such as an O-ring, and is mounted so that its outer peripheral end slightly protrudes from the outer peripheral surface 11 a of the nipple 11 .
The guide portion 12 is a portion that guides the tightening member 20 described later with respect to the nipple 11 so as to reciprocate in the axial direction thereof.

1(a) to 1(d) and FIG. 2 as a specific example of the joint body 10, a nipple 11 is formed to protrude from one end side of the joint body 10 in the axial direction. A plurality of sets (two sets) of sealing members 11b are arranged on the outer peripheral surface 11a of the nipple 11 at predetermined intervals in the axial direction.
A large-diameter guide portion 12 of the nipple 11 is provided in the axially intermediate portion of the joint body 10 so as to radially face the inner surface of a tightening member 20 to be described later. As the guide portion 12, a male screw that is screwed with the inner surface of a tightening member 20, which will be described later, is used.
The other axial end of the joint body 10 is connected to a first tool engaging portion 13 with which a tool (not shown) is engaged, and a pipe connection port (not shown) of another device or pipe body. and a connection portion 14 for.
The first tool engaging portion 13 is formed in a shape that engages with the exposed portion (outer surface) of the joint body 10 so as to be immovably engaged with the tool in the circumferential direction and the tube removal direction U. As shown in FIG. In the illustrated example, the shape of the first tool engaging portion 13 is an octagonal nut shape, a hexagonal nut shape, or the like into which a spanner, a wrench, or the like is fitted.
When an internal thread is formed on the inner surface of the pipe connection port of another device or pipe connected to the pipe joint A, the connecting portion 14 is formed with an external thread corresponding to the internal thread. Further, when an external thread is formed on the outer surface of the pipe connection port, a corresponding internal thread is formed. In the illustrated example, an external thread is provided as the connection portion 14 .
As other examples (not shown), the joint main body 10 and the nipple 11 may be formed separately and attached detachably, one set or three or more sets of the seal members 11b may be arranged, or the first tool engagement portion may be arranged. It is also possible to change the shape of 13 to a shape in which concave portions and convex portions are alternately continuous in the circumferential direction, similar to the second tool engaging portion 23 of the tightening member 20 to be described later.

As with the joint body 10, the tightening member 20 is made of a hard synthetic resin such as super engineering plastic or a hard material such as rust-resistant metal such as stainless steel or brass.
A part of the tightening member 20 in the axial direction has an inner diameter larger than the outer diameter of the plurality of types of tubular bodies B (expanded diameter end portions Bc) inserted into the nipples 11, and the other axial part has a plurality of types of pipes. It has an inner diameter substantially the same as the outer diameter of the body B (expanded diameter end portion Bc).
The tightening member 20 has a moving means 21 provided on its inner surface so as to face the outer peripheral surface 11a of the nipple 11 in the radial direction, a plurality of types of tubular bodies B (diameter-enlarged end portions Bc) into which the nipples 11 are inserted, and radially and a second tool engaging portion 23 with which a tool (not shown) engages.

The moving means 21 is linked to the guide portion 12 of the nipple 11 so as to be rotatable in the axial direction and the circumferential direction. It is a part to move to.
1(a) to 1(d) and FIG. 2 as a specific example of the moving means 21, it is a female thread that is screwed with the male thread of the guide portion 12. is partially formed on one end side in the axial direction (end side in the pipe insertion direction N).
The pressing portion 22 rotates the outer surfaces B2 of the plurality of types of tubular bodies B (diameter-enlarged end portion Bc) toward the outer peripheral surface 11a of the nipple 11 as the moving means 21 rotates relative to the nipple 11 in the tube insertion direction N. It is a part for pressing (tightening) in the direction.
A plurality of types of tubular bodies B (diameter-enlarged end portions Bc) are sandwiched between the outer peripheral surface 11 a of the nipple 11 and the inner surface B1 of the tubular bodies B (diameter-enlarged end portions Bc) by the pressing portion 22 . It is closely attached to the surface 11a and the seal member 11b and is connected in the tube removal direction U so that it cannot be pulled out.

1(a) to 1(d) and FIG. 2 as a specific example of the pressing portion 22, the pressing portion 22 is a tapered surface that gradually decreases in diameter in the direction U where the tube is pulled out. By partially forming the tapered surface that becomes the pressing portion 22 on the other end side of the inner surface of the tightening member 20, it is brought into direct contact with the outer surface B2 of the plurality of types of tubular bodies B (diameter-enlarged end portion Bc).
The second tool engaging portion 23 is formed in a shape that engages with the exposed portion (outer surface) of the tightening member 20 so as not to move in the circumferential direction or the pipe insertion direction N with the tool.
1 to 3 as a specific example of the second tool engaging portion 23, concave portions and convex portions are alternately formed continuously in the circumferential direction along the exposed portion (outer surface) of the tightening member 20. ing.
As other examples (not shown), a linear projection extending in the axial direction or an outer portion of a slider may be provided as the moving means 21 in place of the female screw to move linearly. Modifications other than those shown are possible. Furthermore, an elastically deformable sleeve is interposed inside the pressing portion 22 so that the pressing portion 22 indirectly contacts the outer surface B2 of the tubular body B (expanded diameter end portion Bc) of a plurality of types, It is also possible to change the shape of the second tool engaging portion 23 to a shape such as a hexagonal nut into which a spanner or wrench can be fitted.

On the other hand, the tightening completion position of the tightening member 20 with respect to the nipple 11 associated with the operator's rotating operation differs depending on the difference in the wall thickness dimension of the tubular body B. As shown in FIG. In the case of a plurality of types of tubular bodies B (Ba, Bb) having different outer diameters due to differences in wall thickness, the tightening member 20 for the nipple 11 is adjusted according to the outer diameters of the plurality of types of tubular bodies B (Ba, Bb). Multiple tightening completion positions are different.
1(a) and 1(b), in the case of a tubular body Ba having a large wall thickness and a large outer diameter, the outer surface B2 of the tubular body Ba having a large diameter is pushed during the rotational movement of the tightening member 20. The pressing portion 22 of the tightening member 20 is pressed against. As a result, further tightening movement of the tightening member 20 is disabled. Therefore, the previous tightening completion position (first tightening completion position P1) corresponding to the thick tubular body Ba is in the middle of the rotational movement range of the tightening member 20 .
On the other hand, in the case of the tubular body Bb having a thin wall and a small outer diameter shown in FIGS. However, the pressing portion 22 does not come into contact with the small-diameter outer surface B2 of the tubular body Bb, and there is a space between them. As a result, tightening due to rotational movement of the tightening member 20 is continued, and finally the pressing portion 22 is pressed against the small-diameter outer surface B2 of the tubular body Bb. Therefore, the subsequent tightening completion position (second tightening completion position P2) corresponding to the thin tubular body Bb is arranged on the far side of the previous tightening completion position (first tightening completion position P1).
In the illustrated example, only two types of tubular bodies B, ie, a thick tubular body Ba with a large outer diameter and a thin tubular body Bb with a small outer diameter, are illustrated as multiple types of tubular bodies B. As shown in FIG. Therefore, a plurality of tightening completion positions corresponding to a plurality of types of tubular bodies B (Ba, Bb) accompanying rotational movement of the tightening member 20 with respect to the nipple 11 are the first tightening completion position P1 and the second tightening completion position P2.

The lock member 30 is a stopper that restricts the rotation of the tightening member 20 with respect to the nipple 11 so that the tightening member 20 does not unintentionally loosen from the nipple 11 .
The locking member 30 is composed of an engaging convex portion 31 formed on either the joint body 10 side including the nipple 11 or the tightening member 20 side, and an engaging concave portion 32 formed on the other side.
The engaging convex portion 31 and the engaging concave portion 32 are provided at a plurality of tightening completion positions (first tightening completion positions P1, They are arranged to face each other in the radial direction at the second tightening completion position P2).
In other words, the engaging convex portion 31 and the engaging concave portion 32 are moved to a plurality of tightening completion positions (first tightening completion positions) by rotating the tightening member 20 with respect to the nipple 11 in the tube insertion direction N by the operator's rotating operation. P1, the second tightening completion position P2) is configured to be engaged in the circumferential direction.
As for the form of engagement between the engaging projections 31 and the engaging recesses 32, the tips of the engaging projections 31 and the engaging recesses 32 are elastically deformed or partially destroyed so that they can be overcome in the tightening direction F. However, it is configured to be locked so as not to rotate in the loosening direction L.
Furthermore, the engaging convex portion 31 includes a first convex portion 31a arranged over a plurality of tightening completion positions (first tightening completion position P1, second tightening completion position P2), and a plurality of tightening completion positions (first It is preferable to have a second convex portion 31b arranged at the later tightening completion position (second tightening completion position P2) of the tightening completion position P1 and the second tightening completion position P2).

1 to 3 as a specific example of the lock member 30, an engagement projection 31 is formed on the side of the joint body 10 including the nipple 11, and an engagement recess 32 is formed on the tightening member 20 side. there is The engagement recess 32 is preferably formed at the inner open end of the clamping member 20 .
A plurality of engaging projections 31 are formed continuously at predetermined intervals in the circumferential direction along the outer surface of the joint body 10, and a plurality of groups of the engaging projections 31 are dispersedly arranged.
In the illustrated example, between the guide portion 12 and the first tool engaging portion 13, two groups each of a set of first convex portions 31a and a group of second convex portions 31b are provided as the engaging convex portions 31. They are distributed in the circumferential direction.
The first protruding portion 31a and the second protruding portion 31b are formed to have a mountain-shaped cross section, and the protrusion height and protrusion width of the first protruding portion 31a are smaller than the protrusion height and protrusion width of the second protruding portion 31b. It is preferable to set the outer diameter of the portion where the second convex portion 31b is arranged to be larger than the outer diameter of the portion where the first convex portion 31a is arranged. This makes it easier for the engaging recess 32 to climb over the first projecting portion 31a.
A plurality of engaging recesses 32 are continuously formed at predetermined intervals in the circumferential direction along the entire inner surface of the tightening member 20 .
In the illustrated example, the inner surface of the tightening member 20 is formed continuously at the open end on the one axial end side (the end portion side in the pipe insertion direction N) of the moving means 21 .
In addition, at the first tightening completion position P1 and the second tightening completion position P2, the ends of the engaging convex portion 31 (the first convex portion 31a and the second convex portion 31b) and the engaging concave portion 32 are elastically deformed. Thus, the engaging concave portion 32 is overridden and engaged with the engaging convex portion 31 (the first convex portion 31a and the second convex portion 31b).
In addition, although not shown as another example, the shape and arrangement of the engaging convex portion 31 (the first convex portion 31a and the second convex portion 31b) and the engaging concave portion 32 are changed to a shape and arrangement other than the illustrated example. is also possible. Further, the engaging protrusion 31 (the first protrusion 31a and the second protrusion 31b) may have a fragile portion at the tip that contacts the engaging recess 32 . It is preferable that the strength of the fragile portion and the rupture area be set so that the rupture and overcoming of the engaging recessed portion 32 occurs when the tightening member 20 rotates with respect to the nipple 11 .

According to the pipe joint A according to the embodiment of the present invention, in the case of the tubular body Ba with a large wall thickness and a large outer diameter shown in FIGS. At the previous tightening completion position (first tightening completion position P1), the pressing portion 22 of the tightening member 20 is pressed against the large-diameter outer surface B2 of the thick tubular body Ba. Thereby, the thick tubular body Ba is connected so as not to be pulled out.
At the same time, the engagement protrusion 31 and the engagement recess 32 of the lock member 30 are overridden and engaged. As a result, the tightening member 20 is locked to the nipple 11 so as not to be rotatably movable in the direction opposite to the rotational operation direction (tightening direction F) of the tightening member 20 by the operator (loosening direction L). Therefore, the tightening member 20 is prevented from loosening at the previous tightening completion position (first tightening completion position P1).
Further, in the case of the tubular body Bb having a thin wall and a small outer diameter shown in FIGS. At (the second tightening completion position P2), the pressing portion 22 of the tightening member 20 is pressed against the small-diameter outer surface B2 of the thin tubular body Bb. Thereby, the thin tubular body Bb is connected so as not to be pulled out.
At the same time, the engagement protrusion 31 and the engagement recess 32 of the lock member 30 are overridden and engaged. As a result, the tightening member 20 is locked to the nipple 11 so as not to be rotatably movable in the direction opposite to the rotational operation direction (tightening direction F) of the tightening member 20 by the operator (loosening direction L). Therefore, the tightening member 20 is prevented from loosening even at the subsequent tightening completion position (second tightening completion position P2).
Therefore, even if there are a plurality of types of tubular bodies B (Ba, Bb) with different thicknesses, the tightening member 20 can be locked to the nipple 11 so as not to rotate and loosen regardless of the difference in thickness.
As a result, in order to deal with a plurality of types of tubular bodies with different wall thicknesses, it is necessary to prepare nipples and tightening members dedicated to each size. loosening of the tightening member 20 can be prevented.
For this reason, it is not necessary to separately prepare nipples 11, tightening members 20, and locking members 30 dedicated to each size corresponding to a plurality of types of tubular bodies B (Ba, Bb) having different thicknesses. The work of connecting multiple types of tubular bodies B (Ba, Bb) is facilitated, and the workability is excellent, and at the same time, the cost can be reduced.
Further, even if a plurality of types of tubular bodies B (Ba, Bb) having different thicknesses are hard pipes, the tightening member 20 can be locked against the nipple 11 so as not to be rotatably moved regardless of the difference in thickness to prevent loosening. convenient.

In particular, the engaging convex portion 31 includes a first convex portion 31a arranged over a plurality of tightening completion positions (first tightening completion position P1, second tightening completion position P2), and a plurality of tightening completion positions (second It is preferable to have a second convex portion 31b arranged at the rear tightening completion position (second tightening completion position P2) of the first tightening completion position P1 and the second tightening completion position P2).
In this case, as shown in FIGS. 1(c) and 1(d), in the case of a tubular body Bb that is thin and has a small outer diameter, the tightening completion position ( When the first tightening completion position P1) is reached, the first convex portion 31a and the engagement concave portion 32 are overridden and engaged. Thereafter, as the tightening member 20 is rotated, the overriding engagement between the first convex portion 31a and the engaging recess 32 is continued.
For this reason, the operator suddenly feels that the rotation operation of the tightening member 20 becomes heavy due to the resistance caused by the overriding engagement between the first convex portion 31a and the engaging recess 32 starting from the previous tightening completion position (first tightening completion position P1). perceive what has happened.
By the subsequent rotation operation of the tightening member 20, the overriding engagement between the first convex portion 31a and the engagement recess 32 continues, and when the next tightening completion position (second tightening completion position P2) is reached, The overriding engagement between the second convex portion 31b and the engagement recess 32 is completed.
For this reason, the operator perceives that the rotation operation of the tightening member 20 has become heavier because the resistance increases due to the overriding engagement between the second convex portion 31b and the engagement concave portion 32 .
Therefore, the operator can easily confirm that the tightening member 20 has reached the previous tightening completion position (first tightening completion position P1) or the later tightening completion position (second tightening completion position P2) by the weight of the rotation operation. be able to.
As a result, it is possible to easily and accurately check the optimal tightening state of a plurality of types of tubular bodies B (Ba, Bb) having different wall thicknesses during the tightening work, resulting in excellent workability.
In particular, when the projection height of the first convex portion 31a is set to be smaller than the projection height of the second convex portion 31b, the resistance of the engaging recess 32 to climb over the first convex portion 31a is greater than that of the second convex portion 31a. It is lower than the resistance of the engaging recess 32 to climb over the shaped portion 31b.
For this reason, the engaging recess 32 can smoothly climb over the first convex portion 31a from the front tightening completion position (first tightening completion position P1) to the rear tightening completion position (second tightening completion position P2). become.
Therefore, in the case of the tubular body Bb that is thin and has a small outer diameter, the tightening member 20 is forced to move from the front tightening completion position (first tightening completion position P1) to the rear tightening completion position (second tightening completion position P2). It can be operated without rotation.

Furthermore, the engaging projection 31 has a fragile portion (not shown) at the tip that abuts on the engaging recess 32, and the fragile portion is destroyed by contact with the engaging recess 32 as the tightening member 20 rotates. It is preferable to set it so that it can be overcome by
In this case, when the operator rotates the tightening member 20, the fragile portion at the tip of the engaging projection 31 comes into contact with the engaging recess 32, thereby partially breaking and getting over the engaging recess 32 while rubbing against it. .
For this reason, the operator not only perceives the sound and impact accompanying the breakage of the fragile portion, but also the broken fragile portion rubs against the engaging recess 32, causing resistance, so that the rotation operation of the tightening member 20 suddenly becomes heavy. .
Therefore, the operator can move the tightening member 20 to the previous tightening completion position (first tightening completion position P1) or the later tightening completion position (second tightening completion position P2) by the breaking sound and impact of the fragile portion and the weight of the rotation operation. You can easily check that you have arrived.
As a result, the optimum tightening state of the tubular body B (Ba, Bb) can be easily and more accurately confirmed during the tightening operation, resulting in excellent workability.

In the illustrated example of the above-described embodiment, only two types of tubular bodies B having a thick wall and a large outer diameter and a thin tubular body Bb having a small outer diameter were described as the plurality of types of tubular bodies B, but this is not the case. , and three or more types of tubular bodies B having different outer diameters due to differences in wall thickness may be used.
Even in this case, the same effects and advantages as in the case of using two types of tubular bodies B can be obtained.
Furthermore, only the case where the connecting part 14 is provided with an external thread is shown, but it is not limited to this, and the connecting part 14 can be replaced with one or a plurality of nipples 11 so that another tubular body B can be connected. A structure other than the example shown in the drawings may be used, for example.

A Pipe joint 11 Nipple 11a Peripheral surface 20 Tightening member 22 Pressing part 30 Locking member 31 Engagement convex part 31a First convex part 31b Second convex part 32 Engagement concave part B Pipe Ba Thick pipe Bb Meat Thin tubular body B2 Outer surface P1 Tightening complete position (first tightening complete position)
Tightening completion position after P2 (second tightening completion position)
Insertion space of S tubular body

Claims (3)

a nipple provided along an insertion space for a plurality of types of tubular bodies having different thicknesses;
It is provided so as to be rotatable relative to the plurality of types of tubular bodies inserted along the nipple in the axial direction and the circumferential direction, and the plurality of types of tubular bodies accompany the relative rotational movement with respect to the nipple. a tightening member having a pressing portion that presses toward the outer peripheral surface of the nipple;
a locking member that locks the tightening member so that it cannot rotate relative to the nipple by engagement between an engaging protrusion and an engaging recess provided over the nipple and the tightening member;
one of the engaging convex portion and the engaging concave portion is arranged at a plurality of tightening completion positions corresponding to the plurality of types of tubular bodies accompanying rotational movement of the tightening member with respect to the nipple;
The other of the engaging convex portion and the engaging concave portion is disposed so as to face one of the engaging convex portion and the engaging concave portion in the radial direction and to engage with the engaging convex portion in the circumferential direction,
One of the engaging convex portion and the engaging concave portion that determines the tightening completion position is a first portion arranged over all of the plurality of tightening completion positions, and a second portion located only in the completed position . 2. The pipe joint according to claim 1 , wherein the axial length of said first portion is greater than the axial length of said second portion . The engaging projection has a fragile portion at the tip that abuts on the engaging recess, and the fragile portion is broken by contact with the engaging recess accompanying the rotational movement of the tightening member and overcomes the engaging recess. 3. The pipe joint according to claim 1 or 2, characterized in that it is set.

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