JP2000081174A - Mechanical coupling - Google Patents

Abstract

(57) [Problem] To provide a mechanical joint which does not require disassembly when connecting a pipe to a pipe joint and has a low pipe insertion resistance. A first seal ring chamber provided in an opening by a mechanical joint having a main body, a seal ring inserted in the opening, and an inner nut screwed into a female screw at an end of the opening. And a second seal ring chamber having a smaller diameter provided subsequently to the inner side thereof, and a tapered inner surface connecting the two chambers, and the seal ring is inserted in the first seal ring chamber in advance. The seal ring has a small-diameter flexible ring extending toward the opening end, a disk-shaped spacer, and a steel ball provided on the circumference of the ring. Inserting the pipe into the fitting, screwing the inner nut into the body, the inner nut hits the spacer of the seal ring and pushes the seal ring into the second small seal ring chamber to seal around the pipe. Then, the inner surface of the inner nut pushes down the steel ball attached to the ring to the pipe to prevent it from falling off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical joint which can be used for a water supply pipe or the like.

[0002]

2. Description of the Related Art A plug-in type pipe joint which is a kind of mechanical joint is disclosed in Japanese Patent Application Laid-Open No. 4-203688. This pipe joint has a configuration shown in a sectional view in FIG. In the drawing, P is an inner lining steel pipe having a lining layer. Reference numeral 4 denotes a metal cylindrical pipe joint main body of the pipe joint, the inner peripheral surface of which has a first annular space portion 41 having a tapered surface 411 having a gradually increasing diameter inward, and a parallel to the axis. A second annular space 43 having a large inner surface and both side surfaces perpendicular to the axis is formed in this order from the outside.

In the first annular space 41, a retaining ring 42, which is formed into a C ring with a part of the circumference divided and which can be expanded and contracted in the radial direction, is fitted so as to be movable in the axial center direction. A ring-shaped support rubber that restricts the movement of the retaining ring 42 toward the large-diameter side of the tapered surface 411 and prevents the retaining ring 42 from rattling is fitted in a position farther than the retaining ring 42. I have. In the second annular space 43,
A waterproof packing 44 that elastically contacts the outer peripheral surface of the inner lining steel pipe P is fitted.

A pipe end anticorrosion core 45 is attached to the inner peripheral surface of the pipe joint body 4. This pipe end anticorrosion core 45
Is a cylindrical portion 45 that comes into contact with the inner surface of the inner lining steel pipe P.
Numeral 1 is an integral molding of a synthetic resin material. An annular groove is formed at the outer peripheral end of the cylindrical portion 451, and an O-ring 452 is fitted into the groove to increase the watertightness between the pipe end anticorrosion core 45 and the lining layer of the inner lining steel pipe P. ing.

[0005] When connecting the inner lining steel pipe P to this plug-in type pipe joint, an annular groove is provided on the outer peripheral surface of the steel pipe at a predetermined distance from the tip of the steel pipe, and the inner and outer surfaces of the steel pipe are chamfered. This steel pipe P is inserted into the opening from the end face of the pipe joint, and the tip of the steel pipe is inserted into the pipe end corrosion protection core 45 of the pipe joint.
Abut the wall behind. When the steel pipe is inserted into the pipe joint, the tubular portion 451 of the pipe end anticorrosion core 45 comes into contact with the lining layer on the inner surface of the steel pipe, and the O-ring 452 fitted at the tip of the tubular portion 451 makes the space therebetween watertight. At the same time, the water-stop packing 44 fitted in the second annular space 43 of the pipe joint body 4 elastically contacts the outer peripheral surface of the steel pipe P to make it watertight. In addition, the retaining ring 42 fitted in the first annular space portion 41 fits into the annular groove provided on the outer peripheral surface of the steel pipe. When a force is applied to the steel pipe P such that it comes off from the pipe joint body 4, the retaining ring 42 attempts to move outward together with the steel pipe P, but a force is applied by the tapered surface 411 to reduce the diameter of the retaining ring 42. Therefore, it is possible to prevent the steel pipe P from coming out of the pipe joint body 4 more strongly by biting into the outer peripheral surface of the steel pipe P. Further, when a force is applied so that the steel pipe P goes further into the pipe joint main body 4, the tip of the steel pipe P is connected to the pipe end corrosion protection core 45.
Abuts against the wall at the back of the
It tries to hold down the supporting rubber that supports, so that it can be prevented from entering the back. In this way, the steel pipe can be prevented from falling off and watertight only by being inserted into the pipe joint.

A mechanical joint as shown in the sectional view of FIG. 5 is described in Japanese Patent Application Laid-Open No. 5-346190. According to this, the lining steel pipe 5 whose inner peripheral surface is coated with resin
1 is provided with a first enlarged-diameter receiving port 511 having an inner diameter slightly larger than the outer diameter of the lining steel pipe 52 to be connected,
A second enlarged diameter receiving port 512 is further provided on the tip side thereof. An inclined surface 513 for pressing the rubber ring is formed in a deep portion of the second enlarged diameter receiving port 512, and a screw 514 to which a holding nut is screwed is provided on the outer peripheral surface. A synthetic resin tubular body 515 having an outer diameter substantially equal to the inner diameter of the connected lining steel pipe 52 is provided on the inner side of the socket of the lining steel pipe 51.
Is attached and bonded.

A holding nut 53, a retaining ring 54, a holding ring 55, and a rubber ring 56 are fitted on the outside of the end of the connected lining steel pipe 52 in advance. After being inserted into the mouth, the presser nut 53 fitted in advance is screwed into a screw 514 provided outside the second enlarged-diameter receptacle 512 and screwed. Then
The rubber ring 56, the holding ring 55, and the retaining ring 54 are pressed between the inclined surface of the holding nut 53 and the inclined surface 513 of the second enlarged-diameter receiving port 512, and the rubber ring 56 presses the second enlarged-diameter receiving port 512. The inclined surface 513 and the outer peripheral surface of the end of the connected lining steel pipe 52 are pressure-bonded to ensure watertightness. Further, the diameter of the retaining ring 54 is reduced, and the serrated engaging projections provided on the inner peripheral surface of the retaining ring 54 bite into the outer peripheral surface of the end of the connected lining steel pipe 52, so that the pipe is prevented from coming off. That is.

[0008]

All of these mechanical joints have advantages and disadvantages. FIG.
The mechanical joint shown in (1) has an advantage that it can be connected only by inserting a steel pipe to be connected into the pipe joint, but has a large pipe insertion resistance. When inserting a pipe into a fitting,
Push the retaining ring 42 at the end of the tube, pass it through,
Next, it is necessary to push and expand the water-stop packing 44 and to get over the O-ring 452.

In the mechanical joint shown in FIG. 5, although the resistance at the time of inserting the pipe is not large, the holding nut 53 at the joint is removed, and the holding nut 53, the retaining ring 54, the holding ring 55, and the rubber ring 56 are connected. After fitting to the pipe 52, the pipe and the joint part are combined, then the rubber ring 56, the holding ring 55, and the retaining ring 54 are put into the second enlarged-diameter receiving port 512, and the holding nut 53 is screwed. In addition, it requires disassembly and assembly of the pipe joint.

Accordingly, an object of the present invention is to provide a mechanical joint which does not require disassembly when connecting a pipe to a pipe joint and has a low pipe insertion resistance.

[0011]

SUMMARY OF THE INVENTION A mechanical joint according to the present invention comprises a pipe joint body having an opening capable of receiving a pipe connected to an end thereof and having a screw at the end of the opening, and a pipe connected thereto. A sealing ring having a through hole through which it is flexible and inserted into an opening in the fitting body, a through hole through which a connecting pipe can be passed, and engaging with the screw; (A) the pipe joint body has a cylindrical first seal ring chamber provided in the interior of the screw inside the opening; A second seal ring chamber having a cylindrical shape, which is provided in the opening and is located on the back side following the first seal ring chamber and has a smaller diameter than the first seal ring chamber. Between the first seal ring chamber and the second seal ring chamber (B) the seal ring is inserted into the first seal ring chamber and extends from the seal ring main body to the open end. A flexible ring extending toward the body, and a rigid ring provided between the seal ring body and the flexible ring and facing the open end of the seal ring. A disk-shaped spacer, and a retaining piece provided on a circumference of the flexible ring and movable in a radial direction; (c) the nut is provided on an end face toward the back of the opening; An abutment surface, a tapered inner surface having a diameter increasing from a position close to the abutment surface of the through hole inner surface toward the abutment surface, and the nut is attached to a thread provided with an opening in the pipe joint body. When screwing, the contact surface of the nut is the disk of the seal ring Together abuts against the spacer, the tapered inner surface of the nut Upon retainer piece provided on the flexible ring of the seal ring, and wherein depressing the retainer piece.

It is preferable that the retaining piece is made of a steel ball, and is inserted into a plurality of holes radially opened on the flexible ring of the seal ring. Also,
It is preferable that a pipe end corrosion protection core is provided in the pipe joint body.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A mechanical joint according to an embodiment of the present invention will be described below in detail with reference to the drawings.
1 is a longitudinal sectional view of a mechanical joint according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the mechanical joint shown in FIG. 1, and FIG. 3 is a longitudinal sectional view of the present invention applied to an elbow joint. FIG.

In FIGS. 1 and 2, reference numeral 11 denotes a pipe joint main body. In this embodiment, since the socket is a socket, it has a cylindrical shape, and internal threads 111 and 111 'are attached to inner surfaces of both ends of the opening. There are first cylindrical seal ring chambers 112, 112 'behind the internal threads 111, 111' in the opening. In this figure, the first seal ring chambers 112, 11
The inner diameter of 2 ′ is the same as the internal threads 111, 111 ′. On the back side of the first seal ring chambers 112, 112 ', second seal ring chambers 113, 113' are provided continuously from the first seal ring chamber. It is smaller than the inner diameter of one seal ring chamber. Tapered inner surfaces 114, 114 'are provided so that the diameter continuously decreases from the inner diameter of the first seal ring chamber to the narrower inner diameter of the second seal ring chamber.

A pipe end anticorrosion core 15 is attached to the inner peripheral surface of the pipe joint main body 11, and a cylindrical portion 151 projects from the core in the pipe insertion direction, and is provided at an end of the cylindrical portion. A waterproof packing 152 is fitted in the groove. When the pipe P is inserted into the pipe joint main body 11, the pipe tip portion corresponds to the wall of the pipe end anticorrosion core 15, and the lining layer on the inner surface of the pipe comes into close contact with the water-stop packing 152 so as to increase watertightness.

Numerals 12 and 12 'denote cylindrical inner nuts.
It has a through hole through which the pipe P to be connected can pass, and has external threads 121, 121 'screwed to the internal threads 111, 111' of the pipe joint body 11, and
The end faces on the male thread side have contact surfaces 122, 122 ', and the through-holes increase in diameter from the positions close to the contact surfaces 122, 122' of the through holes toward the contact surfaces 122, 122 '. It has tapered inner surfaces 123, 123 '.

Reference numerals 13 and 13 'denote seal rings, which can be inserted into the first seal ring chambers 112 and 112' of the pipe joint main body 11 to easily pass pipes connected inside in that state. It has a through hole that can be used. The seal rings 13 and 13 'have flexible rings 131 and 131' extending toward the opening end and having an outer diameter smaller than that of the seal ring portion. And rigid ring-shaped spacers 132, 132 'facing the open ends of the pipe joint body of the seal ring. In addition, a plurality of retaining pieces 133 that can move in the radial direction are provided on the circumference of the flexible ring.

The seal rings 13, 13 'are connected to the pipe joint body 1
1, the inner nuts 12, 12 'are inserted into the first seal ring chambers 112, 112'.
11, 111 '. The tapered inner surfaces 123, 123 'of the inner nuts 12, 12' are sealed with the seal rings 13, 13 '.
On the flexible rings 131, 131 'of the above, and push down the retaining piece 133 in the radial direction. The pipe P to be connected is passed through the through-holes of the inner nuts 12 and 12 'and the pipe joint body 1
When it is inserted into the pipe 1, it enters the pipe fitting main body 11 to a position where it abuts inside the pipe end anticorrosion core 15. In this state, the lining layer on the inner surface of the pipe P is pressed against the water-stop packing 152 attached to the outer periphery of the cylindrical portion 151 of the pipe end anticorrosion core 15, so that the space between the pipe end anticorrosion core and the lining layer is watertight. .

When the inner nuts 12 and 12 ′ are screwed into the fitting body 11 with the pipe P inserted into the fitting body 11, the contact surfaces 122 and 122 ′ at the tips of the inner nuts form seal rings 13 and 13. 'Disk-shaped spacers 132, 1
32 ', the seal rings 13, 13' are removed from the first seal ring chambers 112, 112 'by the tapered inner surface 11;
4, 114 'and into the second seal ring chambers 113, 113' of reduced diameter. At the same time, the tapered inner surfaces 123, 1
23 ', the flexible ring 131 of the seal ring,
Since 131 'is pushed inward in the radial direction and pressed against the outer peripheral surface of the tube, the retaining pieces 133 attached to the flexible rings 131 and 131' bite into the outer peripheral surface of the tube. As a result, a pipe retaining performance can be obtained. If a steel ball is used as the retaining piece 133, the relative movement between the inner nuts 12, 12 'and the pipe P and the advancement of the seal rings 13, 13' can be easily performed, and it is easy to bite into the outer peripheral surface of the pipe.

As described above, the seal rings 13 and 13 'have the second seal ring chambers 113 and 11 having a reduced diameter.
3 ', the second seal ring chamber 11
3, 113 'between the inner wall of the pipe and the pipe P
3 'comes into strong contact to obtain watertight performance.

The outer diameters of the disc-shaped spacers 132, 132 'attached to the seal rings 13, 13' are determined by the diameters of the first seal ring chambers 112, 112 'and the second seal ring chambers 113, 113'. In the middle of the diameter. Inner nut 1
When the seal rings 13, 13 'are pushed out of the first seal ring chambers 112, 112' and moved to the second seal ring chambers 113, 113 'by means of 2, 12', tapered inner surfaces 114, 114 therebetween. 'Stops the disc-shaped spacers 132, 132',
Since it does not go further in the back, the seal ring 13,
13 'is not crushed too hard. In particular, when the seal rings 13, 13 'are so-called lip-packed seals having a cut in the center as shown in cross section in FIG. 1, the cuts are completely crushed. Instead, you need to use it with your mouth slightly open. In order to do so, it is extremely useful that the disk-shaped spacer is stopped at the tapered inner surface as in the present invention in order to bring out the effect of the packing.

The tapered inner surfaces 114, 1 of the pipe joint body 11
Since 14 'can be machined and made, its dimensions can be obtained accurately. For this purpose, the disk-shaped spacers 132, 132 'made of a steel plate can be locked at predetermined positions.

FIG. 2 is an exploded perspective view of the mechanical joint of the present invention. In this figure, the water-stop packing 152 is fitted into an annular groove at the end of the tubular portion of the pipe end anticorrosion core. The rings 13, 13 'are assembled into the first seal ring chambers 112, 112' of the fitting body 11, and then the inner nuts 12, 12 'are screwed into female threads 111, 111' at both ends of the fitting body 11. Leave.

A pipe (inner lining steel pipe) to be connected to the mechanical joint assembled as described above is inserted, and is brought into contact with a pipe end anticorrosion core at the back of the pipe joint body. At this time, the pipe passes through the through-hole of the inner nut, and then passes through the through-hole of the seal ring.Since the diameter of the seal ring is not narrowed, the diameter is the same as that made, and the pipe is inserted without resistance Can be inserted. Then tighten the inner nuts 12 and 12
The seal rings 13 and 13 are moved to the second seal ring chamber 11.
Push down to 3,113. At this time, when the disk-shaped spacer comes into contact with the tapered inner surfaces 114, 114 of the pipe joint main body and the inner nut can no longer be tightened, the screwing of the inner nut is stopped, so that the pipe and the mechanical mechanism of the present invention are removed. Connection of the joint is completed.

FIG. 3 shows a cross section of a mechanical joint in which the present invention is applied to an elbow. The basic structure is the same except that a water stop ring having two ridges is used. The reference numerals are the same as those in FIGS.

[0026]

As described above, according to the mechanical joint of the present invention, it is not necessary to disassemble the pipe joint when connecting the pipes, so that the piping work on site is easy. When the pipe is inserted into the pipe joint, the resistance of the pipe insertion is low because the seal ring is expanded.

Also, since the disk-shaped spacer attached to the seal ring is locked by the machined tapered inner surface, the stop position can be accurately controlled, and the compression ratio of the seal ring can be accurately controlled. . Therefore, even when the lip packing is used, the effect can be utilized.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a mechanical joint according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the mechanical joint shown in FIG.

FIG. 3 is a longitudinal sectional view of an elbow joint to which the present invention is applied.

FIG. 4 is a longitudinal sectional view of a plug-in type pipe joint which is a kind of a conventional mechanical joint.

FIG. 5 is a longitudinal sectional view of a conventional mechanical joint.

[Explanation of symbols]

 11 Fitting body 111, 111 'Female thread 112, 112' First seal ring chamber 113, 113 'Second seal ring chamber 114, 114' Tapered inner surface 12, 12 'Inner nut 121, 121' Male screw 122, 122 'abutment surface 123, 123' tapered inner surface 13, 13 'seal ring 131, 131' flexible ring 132, 132 'spacer 133 retaining piece 15 tube end anticorrosion core 151 tubular portion 152 watertight packing 4 tube Joint body 41 First annular space portion 411 Tapered surface 42 Retaining ring 43 Second annular space portion 44 Waterproof packing 45 Tube end anticorrosion core 451 Cylindrical portion 452 O-ring 51, 52 Lining steel pipe 511 First enlarged diameter receiving port 512 Second enlarged diameter receiving port 513 Inclined surface 514 Screw 515 Cylindrical body 53 Presser nut 54 Retaining ring 5 Pressing ring 56 rubber ring P tube

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takuo Nagai 2nd Daifuku, Kuwana-shi, Mie Hitachi Metals Co., Ltd. Kuwana Plant (72) Inventor Matsul Manish 2nd Daifuku, Kuwana-shi, Mie Hitachi Metals Co., Ltd. Kuwana Plant (72) Inventor Hiromi Onuma 75 Nojiri, Ritsuto-cho, Kurita-gun, Shiga Prefecture Inside Sekisui Chemical Co., Ltd. (72) Inventor Tetsuhiro 75, Nojiri, Ritsuto-cho, Kurita-gun, Shiga Prefecture Sekisui Chemical Co., Ltd. F-term (reference) 3H014 DA01 GA06 3H015 AA05 AC03 AE00 CA02 CA11

Claims (3)

[Claims] A flexible fitting having a fitting body having an opening capable of receiving a pipe to be connected to an end thereof and a screw at the opening end thereof, and a through-hole capable of passing a connecting pipe. There is a seal ring inserted into the opening in the fitting body, a cylindrical nut having a through hole through which the connecting pipe can pass, and having a screw capable of engaging with the screw. (A) the pipe joint body has a cylindrical first seal ring chamber provided inside a screw hole in an opening, and the first seal ring chamber in the opening. It is provided on the back side following the chamber, and has a cylindrical second seal ring chamber smaller in diameter than the first seal ring chamber, and between the first seal ring chamber and the second seal ring chamber. From the diameter of the first seal ring chamber to the diameter of the second seal ring chamber (B) the seal ring is inserted into the first seal ring chamber, and is provided extending from the seal ring body toward the opening end. A flexible ring, a rigid disk-shaped spacer provided between the seal ring body and the flexible ring, and facing a hole end of the seal ring; A retaining piece provided on the circumference of the flexible ring and movable in the radial direction; and (c) the nut has an abutting surface on an end face toward the inside of the opening, and an inner surface of the through hole. Having a tapered inner surface that increases in diameter from a position close to the contact surface toward the contact surface, and when the nut is screwed into a screw provided with an opening in the pipe joint body, The contact surface of the nut contacts the disk-shaped spacer of the seal ring and Nut tapered inner surface Upon retainer piece provided on the flexible ring of the seal ring of a mechanical joint, characterized in that depressing the retainer piece. 2. A flexible ring of a seal ring is provided with a plurality of radially opened holes on a circumference, and a retaining piece made of a steel ball is inserted into each of the holes. The mechanical joint according to claim 1, wherein: 3. The mechanical joint according to claim 1, wherein a pipe end anticorrosion core is provided inside.