JP6901134B2 - Pipe fitting structure - Google Patents

Description

The present invention relates to a pipe joint structure.

Conventionally, as a pipe joint structure for connecting pipes to each other, one pipe is connected to one end of the joint body and the other pipe is connected to the other end of the joint body ( See Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2015-137674 Japanese Patent No. 3568906

FIG. 17 shows the pipe joint structure described in Patent Document 1, in which the cap nuts 43 and 44 are screwed into the male screws 41 and 42 at both ends in the axial direction of the joint body 40 and are held by the retainer 46. the cone 45, is pressed into the radial inward direction by the tapered pressing the inner surface of the cap nut 43, is a structure for the pull-out blocking by plastically deforming the first pipe P ₁ · second pipe P ₂ from the outer peripheral surface ..
That is, the first pipe P ₁ is connected (connected) to the joint body 40 by screwing the bag nut 43 into the male screw 41 on the left side of the joint body 40, and the other second pipe P ₂ is the joint body 40. It is a structure that is connected (connected) to the joint body 40 by screwing the bag nut 44 into the male screw 42 on the right side of. In short, as essential a joint body 40, the fitting body 40 interposed therebetween, with a cap nut 43, have a first and second pipe P _1, P ₂ interconnected.

Further, FIG. 18 shows a pipe joint structure described in Patent Document 2. The joint main body 40 is composed of tubular portions 48 and 48 with tapered female threads 47 and an intermediate portion 49, and the joint main body 40 is provided with respect to the joint main body 40. , The left and right screw tightening cylinders 50 and 50 are screwed together. A plurality of elongated holes are formed in the screw tightening cylinder 50 in the circumferential direction, and a beaded body 52 having three independent small ridges 51, 51, 51 is fitted in the elongated holes. By rotating the cylinder portion 48 in the direction of the arrow T, the tightening cylinder body 50 is screwed inward of the joint body 40, and the beaded body 52 rotates and revolves while the outer peripheral surfaces of the _{pipes P 1} and P _{2 are rotated.} in the spiral groove 54 (in plastic deformation) are formed, a state Renju like body 52 bites into the outer circumferential surface of the pipe P _1, P _2, as the pipe P _1, P ₂ has no pull-out from the joint body 40 It is a structure connected to.
In short, also in the case of FIG. 18, the joint body 40 is indispensable, and the first and second pipes P ₁ and P _{2 are held by the screw tightening cylinder 50 and the beaded body 52 with the joint body 40 interposed therebetween.} However, it is connected in a pull-out prevention state.

As described above, the pipe joint structures described in FIGS. 17 (Patent Document 1) and FIG. 18 (Patent Document 2) have the following problems. In other words, (i) the number of parts is large, the structure is complicated, manufacturing is troublesome, and the manufacturing cost cannot be reduced. (ii) The overall axial dimension is large, and the volume of the pipe joint structure is large.
Therefore, an object of the present invention is to solve such problems (i) and (ii) and to provide a compact pipe joint structure having a small number of parts, being inexpensive, and being easy to manufacture.

The present invention relates to a pipe joint structure in which a first pipe and a second pipe are connected to each other; the first and second pipes have a tip diameter-expanded pipe portion extending from the tip surface to a predetermined axial dimension, respectively. Is formed; a tapered stepped portion is formed at the boundary between the tip enlarged pipe portion and the basic diameter pipe portion; and has a gradient portion that abuts on the tapered stepped portion of the first pipe. A first pulling cylinder that pulls the first pipe in the axial direction approaching the second pipe; and a sloped portion that abuts the tapered stepped portion of the second pipe, and the second pipe is the second pipe. A second attracting cylinder that is attracted in the axial direction approaching one pipe is provided; the corresponding portion between the outer peripheral portion of the first attracting cylinder and the inner peripheral portion of the second attracting cylinder is provided. , The first and second pipes are provided with a connecting and holding means for holding the attracted state in which the first and second pipes are attracted to each other ; It is provided with a plurality of sealing recesses having a sealing material that is in close contact with the outer peripheral surface of the portion.

Further, the connection holding means has a locking structure in which the first pulling cylinder and the second pulling cylinder are locked to each other by fitting by approaching each other in the axial direction and rotating at a small angle in the radial direction. Have.
Further, the connection holding means is a screw connection including a male screw and a female screw.

Further, in the connected state, the first pipe and the second pipe have the pipe axis due to the relative circumferential sliding between the sloped portion and the tapered stepped portion with respect to the first and second attracted cylinders. It is configured to be rotatable around and to be prevented from being pulled out by mutual pressure contact between the sloped portion and the tapered stepped portion.

According to the pipe joint structure of the present invention, the number of parts can be extremely reduced and the size can be reduced. It is easy to manufacture and it is possible to reduce costs. Moreover, the connection work can be performed efficiently.

It is a perspective view of the connection completed state which shows one Embodiment of this invention. It is a partial cross-sectional front view seen from the axial direction. It is sectional drawing (iii)-(iii) of FIG. FIG. 2 is a cross-sectional view taken along the line (iv)-(iv) of FIG. It is an exploded perspective view. It is a perspective view explaining the connection work of this invention sequentially. It is a perspective view explaining the next connection operation of this invention in order. It is a perspective view which looked at the 1st pulling cylinder body from a different direction. It is a figure for demonstrating the 1st pulling cylinder, (A) is the front view, (B) is the BB sectional view of (A), (C) is the CC sectional view of (A). Is. It is a perspective view which looked at the 2nd pulling cylinder body from a different direction. It is a figure which shows the 2nd pulling cylinder, (A) is a front view, (B) is a side view, (C) is a rear view. It is a perspective view which looked at the rotation blocking member from a different direction. It is a figure for demonstrating the rotation blocking member, (A) is a front view, (B) is a plan view, (C) is a bottom view, (D) is a left side view. It is sectional drawing explaining the main part and the diameter expansion method of the forming apparatus of the tip diameter expansion tube portion. It is sectional drawing for explaining the brazing work which has been carried out from ancient times to the present, and explaining the brazed pipe connection part. It is sectional drawing of the connection completion state which shows the other two embodiments of this invention. It is sectional drawing which shows the conventional example. It is sectional drawing which shows the other conventional example.

Hereinafter, the present invention will be described in detail based on the illustrated embodiments.
As shown in FIGS. 3, 4 and 6 (A), the first pipe P ₁ and the second pipe P ₂ to be connected to each other extend from the tip surface 3 to the predetermined axial dimension L ₅ . Therefore, the tip diameter expanding tube portion 5 is formed.
A tapered stepped portion 10 is formed at the boundary between the tip diameter-expanded pipe portion 5 and the basic diameter _{pipe portion 6 having the original basic diameter D 0 of the pipe.}

The tapered stepped portion 10 of the first pipe P ₁ has a slope portion 11 abuts the first attracting cylinder that draws in the axial direction X ₁ to approach the first pipe P ₁ to a second pipe P ₂ It has a body 15 (see FIGS. 1 to 5).
Furthermore, the tapered stepped portion 10 of the second pipe P ₂ has a slope portion 11 abuts the second attracting cylinder that draws in the axial direction X ₂ to approach the second pipe P ₂ to the first pipe P ₁ It has a body 20 (see FIGS. 1 to 5).

Then, the outer peripheral portion 16 of the first attracting cylindrical member 15, the corresponding portion of the inner peripheral portion 21 of the second attracting cylindrical body 20, first and second pipe P _1, slide the P ₂ mutually The connection holding means Z for holding the attracted state is provided.
Specifically, in one embodiment of the present invention shown in FIGS. 1 to 13, the connection holding means Z is a mutual axial of the first attracting cylinder 15 and the second attracting cylinder 20. It has a locking structure 100 that locks each other by fitting by approaching directions X ₁ and X ₂ and by rotating a small angle in the radial direction M (see FIG. 7A).

The locking structure 100 will be specifically described below.
As shown in FIGS. 8, 9, 5 and the like, four ridge pairs composed of a first small convex portion 31 and a second small convex portion 32 are formed on the outer peripheral portion of the first pulling cylinder 15. , Arrange with a pitch of 90 ° in the circumferential direction. The outer peripheral portion 16 is left as it is at each interval portion of the four ridge pairs. Further, in each ridge pair, a locking groove portion 23 is formed between the first and second small convex portions 31 and 32.
As shown in FIGS. 10, 11, 5 and the like, four arc-shaped ridge pieces 24 are provided on the inner peripheral surface of the second pulling cylinder 20.

From unconnected state of FIG. 6 (A), as shown in FIG. 6 (B), the the arrows X _1, X ₂ direction and is relatively closer to the first and second attracting cylindrical member 15 and 20, the The arcuate ridge piece 24 rushes between the first and second small convex portions 31 and 32 and the adjacent first and second small convex portions 31 and 32 while sliding in contact with the outer peripheral portion 16. Then, as shown in FIGS. 6 (B) to 7 (A), when the small angle rotation M indicated by the arrow is added (by hand) to the second attracting cylinder 20, the arcuate ridge is formed as shown in FIG. The piece 24 is locked in the locking groove 23.

As described above, the locking structure 100 is formed by the locking groove portion 23 and the arcuate ridge piece 24.
That, connection holding means Z comprises a first attracting cylindrical member 15, the fitting according to the mutual approaching of the axial direction X _1, X ₂ of the second attracting cylindrical member 20, and at the radial direction small angular rotation, The embodiment of FIGS. 1 to 11 shows a case in which the four locking structures 100, 100, 100, 100 that are locked to each other are configured.
The number of locking structures 100 can be increased or decreased (selected) in the range of about 2 to 6.

Next, in FIGS. 12, 13, and 1 to 7, 30 is the first and second attracting cylinders 15, in order to maintain the locked state in the locking structure 100. It is a rotation blocking member that blocks the relative rotation of 20, and the rotation blocking member 30 has four leg pieces 30A that are inserted into the four arcuate slits 25 of the second pulling cylinder 20. .. Specifically, it has a C-shaped ring portion 34 having a cut 33 at one location, and an arc-shaped leg piece 30A projecting from the ring portion 34 in the axial direction (cross section).
A small claw piece 30B is integrally provided on each leg piece 30A. An arcuate space portion 35 along the outer peripheral surface between the pair of small convex portions of the first and second small convex portions 31 and 32 of the first attracting cylinder 15 and the pair of adjacent small convex portions, and the second attracting portion 35. The leg piece 30A is inserted so as to form a skewer in the arcuate slit 25 of the tubular body 20.
During the insertion, the small claw piece 30B elastically deforms, and the small recess 30C reduces the arc length (circumferential width dimension) of the leg piece 30A including the small claw piece 30B. It is provided as a notch in.

As shown in FIGS. 7 (A) to 7 (B), when the leg piece 30A is inserted, the small claw piece 30B is elastically deformed so as to escape into the small recess 30C as described above, and the insertion operation is smooth. When the insertion is completed, the small claw piece 30B pops out from the small recess 30C due to the elastic restoring force and is locked to a part of the second pulling cylinder 20 (FIG. 7 (B), (See FIG. 1). Alternatively, it may be locked to the second small convex portion 32 or the like of the first pulling cylinder 15.
In the illustrated example, since there are as many as four small claw pieces 30B, it is difficult to carelessly or intentionally remove the rotation blocking member 30 from the connection completed state, which is preferable in terms of safety.
Then, 3, as shown in FIGS. 4 and 9, the first attracting cylindrical member 15, the outer peripheral surface of the first and second pipe P _1, P ₂ both distal enlarged tube portion 5,5 Two seal recessed grooves 2 and 2 are provided to house the sealing materials 1 and 1 that are in close contact with each other (such as an O-ring).

As described above, in the illustrated embodiment, the first attracting cylinder 15 is set to have a sufficiently larger axial dimension than the second attracting cylinder 20. In this way, the bending force from the outside to the pipe P _1, P ₂ can be improved flexural strength and rigidity when acted.
In addition, as shown by the alternate long and short dash line in FIG. 4, if the short tubular insert 4 is installed over both the tip diameter-expanded pipe portions 5 and 5, the bending strength can be further improved and the bending strength can be further improved. , Fluid passage resistance can also be reduced. The pipe P _1, P ₂ of the same pipe by cutting the sliced shape, when fabricating the insert 4, upon bending strength improvement, and, upon reduction of the production cost, desirable.

Next, when the present invention is described from another viewpoint while comparing with the configurations shown in FIGS. 17 and 18 as a conventional example, as is clear from FIGS. 1, 3, 4, etc., the first attraction By directly connecting the cylinder body 15 and the second pulling cylinder body 20 by the connection holding means Z, the joint body is omitted.
Further, FIG. 3, the connection completion state shown in FIG. 4, with respect to the first and second attracting cylindrical member 15 and 20, the first pipe P _1, the second pipe P ₂ is the slope portion 11 and the tapered It is configured so that it can rotate around the pipe axis Lp by sliding in the relative circumferential direction with the stepped portion 10 and is prevented from being pulled out by mutual pressure contact between the gradient portion 11 and the tapered stepped portion 10. Has been done.

Next, FIGS. 16A and 16B show two other embodiments of the present invention, and are different from the embodiments described with reference to FIGS. 3 and 4 as follows. That is, the configuration of the connection holding means Z is a screw connection composed of a male screw 37 and a female screw 38.
Further described in FIG. 16 (A), the first pulling cylinder 15 is provided with a male screw 37 on the outer peripheral surface thereof, and the second pulling cylinder 20 has a female screw 38 on the inner peripheral surface. .. In addition, the first and second pulling cylinders 15 and 20 have a hexagonal outer peripheral shape in cross section for hanging work tools such as spanners, and have concave grooves and ridges on the outer peripheral surface in the axial direction. To do. Further, in FIG. 16B, the first pulling cylinder 15 is provided with a female screw 38, and the second pulling cylinder 20 has a male screw 37 on the inner peripheral surface. The first and second attracting cylinders 15 and 20 have a hexagonal cross-sectional outer peripheral shape, or have concave grooves or ridges on the outer peripheral surface in the axial direction.
The rest of the configuration, the first and second pipe P _1, P ₂ of the gradient portion 11 in contact with the tapered stepped portion 10, the point having the respective first and second attracting cylindrical member 15, 20 and, first attracting cylindrical member 15 has two seal grooves 2,2, the sealing member 1, 1 O-ring or the like which is furnished there, first and second pipe P _1, P ₂ It is the same as the above-described embodiment in that it presses against the outer peripheral surfaces of the tip diameter-expanded pipe portions 5 and 5 to form a sealing action.

Further, FIG. 16 (A) each of the embodiments shown in (B) is, in the connection completion state, the first-second attracting cylindrical member 15 and 20, the first pipe P _1, the second pipe P ₂ Is rotatable around the pipe axis Lp by sliding in the relative circumferential direction between the gradient portion 11 and the tapered stepped portion 10, and by mutual pressure contact between the gradient portion 11 and the tapered stepped portion 10. It is the same as the embodiment described with reference to FIGS. 1 to 15 in that it is configured so as to be prevented from being pulled out. Further, also in each of the embodiments shown in FIGS. 16A and 16B, the joint body is completely omitted.

Te is at the present invention, it is the basic one configuration requirements to provide a distal enlarged tube portion 5 in each pipe P _1, P _2. Therefore, the tip diameter expanding tube portion 5 will be described below.
As shown in FIG. 14, _{the tip of the pipe P 0 to} be machined is inserted into the hole 26A of the split die 26, and the cross-section fan-shaped enlarged diameter piece 27 divided into four (or more) is inserted into the pipe P. Insert to a predetermined depth with respect to _0. When the tapered male mold 28 is pushed into the tapered hole portion 29 formed by the divided diameter-expanding pieces 27 in the direction of arrow E, the diameter-expanding pieces 27 are as shown in FIGS. 14A to 14B. Moves in the radial outward direction R, and the tip diameter expanding tube portion 5 is formed (processed).

In order to form the tapered stepped portion 10, the enlarged diameter piece 27 is provided with the tapered portion 27A, and the hole portion 26A of the mold 26 is provided with the tapered portion 26B.
After that, the mold 26 is divided and operated in the diameter- _{expanding direction, and the processed pipe P 0} is pulled out to manufacture _{pipes P 1} and P ₂ with a tip diameter-expanding pipe portion 5 as shown in FIGS. Will be done.

Since ancient times, the manual work tool for diameter expansion shown in FIG. 14 has been widely known. The reason is that the brazed pipe connection 63 as shown in FIG. 15 has been used for a refrigerant pipe and a household hot water supply (water) pipe for a long time. That is, because of the brazing pipe connection 63 that has been practiced for a long time, it is necessary to pre-process the tip diameter expanding pipe portion 5 shown in FIGS. 3 and 4 for one of the pipes 61. (The other pipe 62 is inserted into the enlarged diameter pipe portion 5 as it is without being processed, and the mutual fitting surface portion X ₅ is brazed.)
In this way, the present inventor focused on the diameter-expanding work tool widely used for pipe connection work by brazing and the tip-diameter-expanded pipe portion that can be easily machined by the tool, and FIGS. 1 to 7 show. By combining the unique shape and structure as shown, you can work safely without using heat such as brazing, and it is compact in both the axial (axial) direction and the radial direction, and the pipe. A pipe joint structure with excellent connection workability is proposed here.

The present invention is not limited to the above-described embodiment unless the gist thereof is changed, and the design can be freely changed. For example, the shape of the rotation blocking member 30 can be changed, and each leg piece 30A is centered. It is composed of a cross-sectional arc-shaped insertion piece portion without a locking claw and a fine rod-shaped or spear-shaped rod portion having a locking claw at the tip along the left and right sides thereof. Alternatively, a small hook claw that elastically deforms outward (or inward) radially is formed on the leg piece 30A.
Fluids that may pipe joint structure applied to the present invention, the refrigerant gas, air, water, a free hot water or the like, first and second pipe P _1, P ₂ has a diameter machining easier copper, aluminum, stainless steel Metals such as steel are suitable. When the fluid is water or hot water containing a refrigerant, gas, or chlorine gas, the material of the sealing material 1 is preferably corrosion-resistant rubber. Since the recent progress of corrosion-resistant rubber materials is remarkable, the applicable fluids of the pipe joint structure provided with the sealing materials 1 and 1 as in the present invention are refrigerant, corrosive gas, water / hot water containing chlorine gas, etc. It can be said that there is a high possibility that it will be expanded to.

As described in detail above, the present invention has _{a pipe joint structure in which the first pipe P 1} and the second pipe P ₂ are interconnected; the first and second pipes P ₁ and P ₂ are respectively. is distal radially enlarged tube portion 5 across from the front end surface 3 in a predetermined axial dimension which L ₅ formed; the boundary between the distal enlarged tube portion 5 and the base diameter tubular portion 6, the tapered stepped portion 10 It is formed; has the above-mentioned first pipe P ₁ of the tapered stepped portion abuts gradient 11 to 10, the that draws in the axial direction X ₁ approaching the first pipe P ₁ to a second pipe P ₂ 1 attracting and allowed tubular body 15; in the second the tapered stepped portion 10 of the pipe P ₂ has a slope portion 11 abuts, the axial direction X of the second pipe P ₂ approaches the first pipe P _{1 A second} attracting cylinder 20 that is attracted to 2 is provided; a corresponding portion between the outer peripheral portion 16 of the first attracting cylinder 15 and the inner peripheral portion 21 of the second attracting cylinder 20 is provided. Since the configuration is provided with the connection holding means Z for holding the attracted state in which the first and second pipes P ₁ and P ₂ are attracted to each other, the number of parts is small and a compact pipe joint can be inexpensively manufactured. It is now possible to provide. In particular, the axial dimension can be remarkably shortened and compacted as compared with the conventional pipe joint structure having a joint body.

Further, the connection holding means Z is the said first attracting cylindrical member 15 at second attracting axial direction X ₁ each other of not tubular body 20, X ₂ of the fitting and the radial direction small angular rotation M by the approaching Since it has a locking structure 100 that locks each other, the pipe connection work can be easily and quickly performed by the operator. In particular, pipe connection work in high places and narrow spaces can be performed efficiently, easily and quickly.
Further, since the connection holding means Z is a screw connection composed of a male screw 37 and a female screw 38, the number of parts can be further reduced, work can be performed reliably and quickly with a conventional work tool, and the withdrawal force is large. ..

Further, the first attracting cylindrical member 15, a plurality of seals concave with a sealing member 1 is furnished in close contact with the outer peripheral surface of the first and second pipe P _1, P ₂ both distal enlarged tube portion 5,5 since the configuration that includes a groove 2,2, high flexural rigidity in a case where the first and second pipe P _1, P ₂ bending force is applied is, and external leakage even less likely to occur in the fluid, sealing performance Is also excellent.
Further, by directly connecting the first pulling cylinder 15 and the second pulling cylinder 20 by the connection holding means Z, the joint body is omitted, so that the dimensions in the axial direction can be made compact. Can be achieved. Moreover, the first pipe P ₁ and the second pipe P ₂ can be connected (connected) at the same time, and the workability is extremely good.

_{Further, in the connected state, the first pipe P 1} and the second pipe P ₂ are relative to the first and second attracting cylinders 15 and 20 with respect to the gradient portion 11 and the tapered stepped portion 10. Since it is configured so that it can rotate around the pipe axis Lp by sliding in the circumferential direction and is prevented from being pulled out by mutual pressure contact between the gradient portion 11 and the tapered stepped portion 10. Even if the rotational torque around the axis Lp is transmitted from the other end side of the second pipes P ₁ and P ₂ , the rotational torque can be cleverly absorbed (cut off) by the gradient portion 11 and the tapered stepped portion 10. .. Moreover, it has a large pull-out prevention force and does not pull out unexpectedly.

1 Seal material 2 Seal concave groove 3 Tip surface 5 Tip diameter expansion pipe part 6 Basic diameter pipe part
10 Tapered stepped part
11 Gradient
15 1st pulling cylinder
16 Perimeter
20 Second pulling cylinder
21 Inner circumference
30 Rotation blocking member
37 Male screw
38 female screw
100 Locking structure D ₀ Basic diameter P ₁ 1st pipe P ₂ 2nd pipe L ₅ Axis direction dimension Lp Pipe axis M Small angle rotation X ₁ , X ₂ Axial direction Z Connection holding means

Claims (4)

In the fitting structure that connects the first pipe (P ₁ ) and the second pipe (P ₂ ) to each other,
In each of the first and second pipes (P ₁ ) and (P ₂ ), a tip diameter-expanded pipe portion (5) is formed from the tip surface (3) over a predetermined axial dimension (L _5).
A tapered stepped portion (10) is formed at the boundary between the tip enlarged diameter pipe portion (5) and the basic diameter pipe portion (6).
Abutting slope portion to the tapered stepped portion (10) of said first pipe (P ₁₎ has a (11), approaching the first pipe (P ₁₎ in the second pipe (P ₂₎ axial The first pulling cylinder (15) that pulls in the direction (X _{1) and}
The tapered stepped portion (10) in contact with the slope portion of the second pipe (P ₂₎ has a (11), approaching the second pipe (P ₂₎ to the first pipe (P ₁₎ Axial With a second pulling cylinder (20) that pulls in the direction (X _2),
The first and second pipes (P) correspond to the outer peripheral portion (16) of the first attracting cylinder (15) and the inner peripheral portion (21) of the second attracting cylinder (20). ₁ ) The connection holding means (Z) for holding the attracted state in which (P ₂ ) is attracted to each other is provided.
The first pulling cylinder (15) is a sealing material (1) that is in close contact with the outer peripheral surfaces of the tip diameter-expanded pipe portions (5) and (5) of both _{the first and second pipes (P 1} ) and (P _2). A pipe joint structure characterized by having a plurality of seal recessed grooves (2) and (2) inside. _{The connection holding means (Z) is fitted by the axial directions (X 1} ) and (X ₂ ) of the first pulling cylinder (15) and the second pulling cylinder (20) approaching each other, and the radial direction. The pipe joint structure according to claim 1, which has a locking structure (100) that locks each other by a small angle rotation (M). The pipe joint structure according to claim 1, wherein the connection holding means (Z) is a screw connection including a male screw (37) and a female screw (38). _{In the connected state, the first pipe (P 1} ) and the second pipe (P ₂ ) are tapered with the slope portion (11) with respect to the first and second pulling cylinders (15) and (20). It can rotate around the pipe axis (Lp) by sliding in the relative circumferential direction with the stepped portion (10), and is pulled out by mutual pressure contact between the sloped portion (11) and the tapered stepped portion (10). The pipe fitting structure according to claim 1, 2 or 3, which is configured to be blocked.

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