JP2002130563A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint capable of reducing labor and time requiring to connect two tubular members. SOLUTION: A pair of fitting members 1, 2 is rotably and undetachably connected to each other. A tapered female threaded portion 11 on which a gas tube is screwed and fastened is on one of the fitting member 1 whereas a tapered male threaded portion 21 on which it is screwed and fastened to the gas induction inlet of a gas appliance is on the other of the fitting member 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint used when connecting pipes or a pipe to a connection port of an apparatus.

[0002]

2. Description of the Related Art As a conventional joint of this type, there is a union joint shown in FIG. This union joint has a pair of joint members a and b and a nut member c. The joint members a and b are provided with tapered female screw portions a1 and b1, respectively. One end of the nut member c is rotatably connected to one of the joint members a, and is connected to the joint member b from the joint member a side.
It is immovably engaged in the direction toward the side. The other end of the nut member c is screwed to the other joint member b.

When connecting two pipes (not shown) using the union joint having the above-described structure, first, joint members a,
The pipes are screwed and fixed to the respective tapered female screw portions a1 and b1 of b. Next, the nut member c is rotated and tightened so that the end faces of the joint members a and b are brought into pressure contact with each other, and the joint members a and b are air-tightly connected. As a result, the two pipes are airtightly connected via the union joint.

[0004]

In the case where two pipes are connected by the above-mentioned conventional union joint (pipe joint),
Each pipe is screwed and fixed to a pair of joint members a and b,
Since it is necessary to connect and fix the pair of joint members a and b with the nut member c, the screwing operation must be performed three times.
There is a problem that a great deal of labor and time are required for the connection work.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention has a pair of joint members, and adjacent ends of the pair of joint members are rotatable with each other, and are mutually rotatable. Connection screw portions are connected to each other so as to be inseparable in a detaching direction, and the tubular members are screwed and fixed to the mutually separated ends of the joint members. A screwdriver such as a spanner is provided on the outer peripheral portion of each joint member. It is characterized in that a tool hook portion to be combined is provided. In this case, at least one of the joint members is made of an insulating material, or at least one of the contact portions of the pair of joint members that contact each other is provided with an insulating layer that insulates between the pair of joint members, The joint member is rotatably connected via an intermediate member, and at least one of the pair of joint members and the intermediate member is formed of an insulating material, or the pair of joint members is formed of an intermediate member. It is preferable to provide an insulating layer that is rotatably connected via the first member and that insulates between the one joint member and the intermediate member on at least one of the contact portions between the intermediate member and the one joint member.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. In all the embodiments described below, the present invention is applied to an insulating joint for a gas pipe, but the present invention can be applied to an insulating joint for another pipe.

FIGS. 1 and 2 show a first embodiment of the present invention. The pipe joint A of this embodiment has a pair of joint members 1 and 2. Each of the joint members 1 and 2 has a tubular shape, and ends adjacent to each other (the right end of the joint member 1 and the left end of the joint member 2. Hereinafter, left and right mean left and right in each drawing. ) Are rotatably connected to each other. In this joint A, the right end of the joint member 1 is
Are rotatably fitted to the inner periphery of the left end of the joint member 1. Alternatively, the left end of the joint member 2 may be rotatably fitted to the inner periphery of the right end of the joint member 1. The joint members 1 and 2 are connected to each other in a state where they are fixed to each other by a retaining ring 51. As long as the joint members 1 and 2 cannot be separated in a direction away from each other, the joint members 1 and 2 may be movable in a predetermined range in the axial direction of each other. The joint members 1 and 2 are sealed by O-rings 52 and 53 and sealed by a metal fire-resistant ring 54.

A tapered female thread (connection thread) 11 for a pipe is formed on the inner peripheral surface of the left end of one of the joint members 1 (the end portion apart from the other joint member 2). A tapered male screw portion (not shown) for a pipe formed at a distal end portion of a rigid gas pipe (tubular member) such as a steel pipe is screwed and fixed to the tapered female screw portion 11. A tapered male screw (connection screw part) 21 for a pipe is formed on the outer periphery of the right end of the other joint member 2 (the end apart from the one joint member 1). The tapered male screw portion 21 is screwed and fixed to a pipe tapered female screw portion formed at the connection port of the gas appliance. It should be noted that a tapered male thread portion for pipe is formed on one joint member 1 and the other joint member 2 is formed.
You may form the taper female thread part for pipes. Moreover, you may form the taper female screw part for pipes or the taper male screw part in both of the joint members 1 and 2. Furthermore, taper screws 11 and 12 for pipes
Instead of 1, a straight screw may be formed.

A tool hook 12 is formed on the outer peripheral surface of the left end of one joint member 1 protruding from the other joint member 2. The tool hook 12 engages a screwdriver such as a spanner when screwing a gas pipe or the like to the tapered female screw 11 and has a hexagonal or octagonal cross section. The tool holder 12 may have two parallel surfaces. When a screwdriver that can rotate a member having a circular outer peripheral surface is used, the tool holder 12 may have a circular cross section. At the left end of the other joint member 2, a tool hook 22 is formed. The tool hook 22 is configured similarly to the tool hook 12.

For example, when a gas pipe (tubular member) is connected to a gas inlet (tubular member) of a gas appliance using the pipe joint A having the above-described configuration, a tapered male screw portion is previously formed on the outer peripheral surface of the distal end portion of the gas pipe. At the same time, a tapered female thread is formed on the inner peripheral surface of the gas inlet. Then, the tapered male screw part of the gas pipe is screwed and fixed to the tapered female screw part 11 of the joint member 1, and the tapered male screw part 21 of the joint member 2 is screwed and fixed to the gas inlet of the gas appliance. Thereby, the gas pipe is connected to the gas appliance via the pipe joint A. Of course, if a tapered female thread is formed in the joint member 2 instead of the tapered male thread 21, two gas pipes (tubular members) can be connected.

According to the pipe joint A according to the present invention, the gas pipes and the gas introduction holes, which are two tubular portions, need only be screwed and fixed to the two joint members 1, 2, respectively. Need not be further pressed and fixed by the nut member. Therefore, the labor and time required for connection can be reduced by the amount of rotating and tightening the nut member.

Next, another embodiment of the present invention will be described. The following embodiments are different from the above embodiments mainly in that they have an electrical insulating function, and other configurations are the same as those of the above embodiments. Therefore, here, only the configuration different from the above configuration will be described, and the same reference numerals are given to the same portions as those in the above embodiment, and the description thereof will be omitted. In addition, since each of the embodiments described below has the same effects as those of the above-described embodiments, only the effects specific to each embodiment will be described in the following embodiments.

FIGS. 3 and 4 show a second embodiment of the present invention. In the pipe joint B of this embodiment,
One joint member 1 is made of a metal such as brass, cast iron, or steel, while the other joint member 2 is made of an electrically insulating material. As the insulating material, it is desirable to use a material having sufficient strength for connection of a gas pipe or gas equipment. As such an insulating material, for example, there is a ceramic or a fiber-reinforced plastic having an insulating property. One joint member 1 may be made of an insulating material, the other joint member 2 may be made of a metal, and both joint members 1 and 2 may be made of an insulating material.

As described above, at least one joint member 1
(2) Pipe joint B composed of an electrically insulating material
In this case, electricity can be reliably prevented from flowing between two tubular members such as a gas pipe connected via the joint A. Therefore, each tubular member can be prevented from being electrically corroded.

In the conventional insulating joint, an insulating layer is usually formed on the tapered screws 11 and 21. Therefore, when a pipe or device is once screwed to each of the tapered screws 11 and 21, it is removed. Since part of the insulating layer is broken, it cannot be used again as an insulating joint. In this regard, in the pipe joint B, since the joint member 1 (2) is made of an insulating material, the insulating function may be impaired even if screwing and removing the tapered screw portions 11 and 21 are repeated. Absent. Therefore, according to the joint B, it can be reused any number of times, and can be connected again after removing the connected pipe.

FIGS. 5 and 6 show a third embodiment of the present invention. In the pipe joint C of this embodiment,
Each of the pair of joint members 1 and 2 is made of metal. Therefore, when the joint members 1 and 2 come into direct contact, electricity flows between them. Then, the joint member 1,
An insulating layer 3 and an insulating ring 55 are provided to electrically insulate the two.

The insulating layer 3 is formed, for example, by applying or spraying an insulating paint or coating an insulating material, and has a thickness of about 50 to 200 μm. The insulating layer 3 is a joint member 2 into which the right end of the joint member 1 is inserted.
Of the joint member 1 and a step surface 24 facing the right end surface 14 of the joint member 1. Therefore, the joint members 1 and 2 are rotatably in contact with each other via the insulating layer 3 and do not directly contact. The insulating layer 3 may be formed on the outer peripheral surface (contact portion) 13 and the right end surface 14 of the right end portion of the joint member 1 inserted into the joint member 2.
The refractory ring 54 directly contacts the joint member 1 but contacts the joint member 2 via the insulating layer 3.
Therefore, the joint members 1 and 2 are not electrically connected via the fire-resistant ring 54.

When a large force acts between the joint members 1 and 2 so as to approach them, the refractory ring 54 shrinks in the axial direction of the joint members 1 and 2 and the step surface 15 of the joint member 1 and the left end of the joint member 2. The surface 25 may come into contact with the surface 25. Therefore, between the step surface 15 and the left end surface 25, ceramic,
An insulating ring 55 made of an insulating resin or the like is provided. This prevents the step surface 25 of the joint member 1 from directly contacting the left end surface 15 of the joint member 1. In addition, the insulating ring 55 has an L-shaped cross section, and a part thereof extends to the left from between the step surface 15 and the left end surface 25 to cover a part of the tool hooking portion 12. what if,
The insulating ring 55 is the outer periphery of the joint member 1 (the tool hook 12).
If rainwater is attached to the joint member 1 and the left end of the joint member 2 so as to straddle, electricity flows between the joint members 1 and 2 via the rainwater. This is because such a so-called jump current is prevented by the insulating ring 55. Insulation ring 55
May cover the left end of the tool holder 22.
When there is no possibility that the step surface 15 and the left end surface 25 are in direct contact with each other, or when the insulating layer 3 is also formed on the left end surface 25 of the joint member 2 and the tool hooking portion 22 extending rightward therefrom, the insulating ring 55 may not be provided.

FIGS. 7 and 8 show a fourth embodiment of the present invention. In the pipe joint D of this embodiment,
A tubular intermediate member 4 is provided between the joint members 1 and 2. A straight external thread portion 41 is formed on the outer peripheral surface of the left end portion of the intermediate member 4. This male screw part 41 is
The joint member 1 is screwed into a female screw portion 16 formed on the inner peripheral surface at the right end. Then, the male screw part 41 is connected to the female screw part 16.
The intermediate member 4 is fixed to the joint member 1 by pressing the flange 42 formed on the outer peripheral surface of the intermediate member 4 into contact with the right end surface 15 of the joint member 1 via a gasket 56 made of an insulating material. Have been. A female screw portion may be formed in the intermediate member 4, and the right end of the joint member 1 may be screwed into the female screw portion. The insulating ring 55 covers the space between the right end surface 15 of the joint member 1 and the flange portion 41 of the intermediate member 4 and the subsequent tool hook 12 of the joint member 1. The insulating ring 55 does not need to be provided.
The right end of the intermediate member 4 is rotatably fitted to the inner peripheral surface 23 of the joint member 2. The retaining ring 51, the O-rings 52 and 53, and the fire-resistant ring 54 are provided between the intermediate member 4 and the joint member 2. The left end of the joint member 2 may be rotatably fitted to the inner periphery of the right end of the intermediate portion.

At least one of the joint members 1, 2 and the intermediate member 4 is made of an insulating material. In the case of this embodiment, the joint members 1 and 2 are made of metal, and the intermediate member 4 is made of an insulating material. Of course, the joint member 1 or 2 may be made of an insulating material, and the intermediate member 4 may be made of a metal. Alternatively, the joint member 1 and the intermediate member 4 may be made of metal, and the joint member 2 may be made of an insulating material.

In the pipe joint D of this embodiment, when the tubular member is screwed and fixed to the tapered screw portion 11, a wrench or the like is engaged with the tool hooking portion 12, and the tubular member is screwed into the tapered screw portion 12. At the time of fixing, a wrench or the like is engaged with the tool holder 22. However, when the tubular member is screwed and fixed to the tapered screw portion 11 by mistake, a spanner is hung on the tool hooking portion 22. Conversely, when the tubular member is screwed and fixed on the tapered screw portion 21, the spanner is hooked on the tool hooking portion 12. May be multiplied. In such a case, since the intermediate member 4 and the joint member 2 are rotatable, no rotational force acts on the intermediate member 4. Therefore, even if the strength of the intermediate member 4 is relatively low, it is not damaged. This is the same in the embodiments described below.

FIGS. 9 to 11 show a fifth embodiment of the present invention. The pipe joint E of this embodiment is a modification of the pipe joint D, and the joint members 1 and 2 and the intermediate member 4 are all made of metal. However, the joint member 1 and the intermediate member 4 are electrically insulated by the insulating layer 6 formed between their contact surfaces. FIG.
As shown in FIG. 5, the insulating layer 6 is formed by the external thread portion (contact portion) 41 of the intermediate member 4 and the intermediate member 4 following the external thread portion 41 because the joint member 1 and the intermediate member 4 are screwed and fixed. And the left end face 43 on the inner peripheral side of the gasket 56 of the flange portion 42. Thus, the joint member 1 and the intermediate member 4 are electrically insulated. It is desirable that the thickness of the insulating layer 6 be about 50 to 200 μm. The insulating layer 6 may be formed on the female screw portion (contact portion) 16 of the joint member 1 or on the female screw portion 16 and its vicinity.

In this pipe joint E, the insulating layer 6 is formed at the screwing portion between the joint member 1 and the intermediate member 4, but the intermediate member 4 is still screwed and fixed to the joint member 1, and It is not removed from the member 1. Unlike the case where the exposed insulating layer is formed on the tapered screw portions 11 and 21 to which the tubular member is screwed and fixed, there is no fear of damaging the insulating layer 6 and the insulating function can be maintained semipermanently.

The embodiment shown in FIGS. 12 and 13 is a modification of the embodiment shown in FIGS. 9 to 11. In the pipe joint F of this embodiment, the left end of the intermediate member 4 The right end of the joint member 1 is rotatably fitted. And a retaining ring 51, an O-ring 52,
53 and a refractory ring 54 are provided. A male screw portion 44 is formed at the right end of the intermediate portion 4, and the male screw portion 44 is formed on the inner periphery of the left end portion of the joint member 2.
6 is screwed. Then, the male screw portion 44 is screwed into the female screw portion 26 until the step surface 45 formed on the outer periphery of the intermediate member 4 abuts on the left end surface 25 of the joint member 2 via the gasket 56, so that the intermediate member 4 is connected to the joint member 2. Fixed. The outer peripheral surface of the intermediate member 4 between and following the left end surface 25 and the step surface 45 is covered with an insulating ring 55.

An insulating layer 6 similar to the embodiment shown in FIGS. 9 to 11 is formed on a male screw portion (contact portion) 44 of the intermediate member 4. Of course, the insulating layer 6 may be formed on the female screw portion (contact portion) 26. Further, a female screw portion is formed on the inner periphery of the right end of the intermediate member 4, and the joint member 2 is
May be screwed together, in which case an insulating layer may be formed on any of the screw portions.

The embodiment shown in FIGS. 14 and 15 is a modification of the embodiment shown in FIGS. 1 and 2 or the embodiment shown in FIGS. 3 and 4. A coated steel pipe (tubular member) T is connected to the member 1,
The connecting portion of the coated steel pipe T is covered by a skirt portion 17. That is, the coated steel pipe T is composed of a steel pipe T1 and a resin jacket T2 that covers the outer periphery of the steel pipe T1, and a tapered male screw part T3 that is screwed to the tapered female screw part 11 is formed at the tip of the steel pipe T1. By forming this tapered male screw portion T3, the tip of the jacket T2 is cut off,
The tapered male thread is exposed to the outside.

The joint member 1 is formed with a cylindrical skirt 17 following the tool hook 12 and concentrically therewith. The inner diameter of the skirt portion 17 is
The diameter is larger than the maximum diameter of the valley. In particular, in this embodiment, the outer diameter of the jacket T2 is equal to or slightly larger than that of the jacket T2 so that the coated steel pipe T screwed and fixed to the tapered female screw 11 can be inserted. In addition, tapered female screw 1
When the tapered male screw portion T3 is screwed and fixed to 1, the base end side (large diameter side) of the tapered male screw T3 is exposed from the tapered female screw 11 to the outside. The length of the skirt 17 is set.

The joint G having such a skirt portion 17
According to the above, the tapered female screw 1 of the tapered male screw T3 of the steel T1
The portion exposed from 1 is covered by the skirt 17. Therefore, it is possible to prevent the part from getting wet and rusting with rainwater. In order to further improve the rust prevention effect, it is desirable that the inner diameter of the skirt portion 17 be substantially the same as the outer diameter of the jacket G2. The point of forming the skirt 17 following the tool hook 12 is that the pipe joints A and B
It is desirable to apply to other pipe joints C to F other than the above.

[0029]

As described above, according to the present invention, it is possible to reduce the labor and time required for connecting two tubular members.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of the present invention.

FIG. 2 is a front view of the embodiment.

FIG. 3 is a sectional view showing a second embodiment of the present invention.

FIG. 4 is a front view of the embodiment.

FIG. 5 is a sectional view showing a third embodiment of the present invention.

FIG. 6 is a front view of the embodiment.

FIG. 7 is a sectional view showing a fourth embodiment of the present invention.

FIG. 8 is a front view of the embodiment.

FIG. 9 is a sectional view showing a fifth embodiment of the present invention.

FIG. 10 is a front view of the embodiment.

FIG. 11 is an enlarged sectional view of a main part of the embodiment.

FIG. 12 is a sectional view showing a sixth embodiment of the present invention.

FIG. 13 is a front view of the embodiment.

FIG. 14 is a sectional view showing a seventh embodiment of the present invention.

FIG. 15 is a front view of the embodiment.

FIG. 16 is a half sectional view showing an example of a conventional pipe joint.

[Explanation of symbols]

 A pipe joint B pipe joint C pipe joint D pipe joint E pipe joint F pipe joint G pipe joint T coated steel pipe (tubular member) 1 joint member 2 joint member 3 insulation layer 4 intermediate member 6 insulation layer 11 taper female screw (connection screw part) 13 outer peripheral surface (contact portion) 16 female screw portion (contact portion) 12 tool hook portion 21 taper male screw (connection screw portion) 22 tool hook portion 23 inner peripheral surface (contact portion) 26 female screw portion (contact portion) 41 male screw portion ( (Contact part) 43 Male thread (contact part)

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Jun Okubo 1-5-20 Kaigan, Minato-ku, Tokyo Inside Tokyo Gas Co., Ltd. (72) Inventor Shigeru Katagiri 19-18 Sakuradacho, Atsuta-ku, Nagoya City, Aichi Prefecture Toho Gas (72) Inventor Kazuma Takahashi 3-1-8 Kitahonmachi, Joetsu-shi, Niigata Koyo Sangyo Co., Ltd. F-term (reference) 3H013 JC04 3H016 FA01

Claims (5)

[Claims] 1. A pair of joint members, wherein adjacent end portions of the pair of joint members are connected to each other so as to be rotatable and non-detachable in a direction away from each other, and separate ends of each joint member. A pipe joint in which connection screw portions to which a tubular member is screwed and fixed are provided, and a tool hook portion for engaging a screwdriver such as a spanner is provided on an outer peripheral portion of each joint member. 2. The pipe joint according to claim 1, wherein at least one of said joint members is made of an insulating material. 3. The pipe joint according to claim 1, wherein an insulating layer for insulating between the pair of joint members is provided on at least one of the contact portions of the pair of joint members that come into contact with each other. 4. The pair of joint members are rotatably connected via an intermediate member, and at least one of the pair of joint members and the intermediate member is formed of an insulating material. The pipe joint according to claim 1, wherein 5. The pair of joint members are rotatably connected via an intermediate member, and the one joint member and the intermediate member are connected to at least one of the contact portions between the intermediate member and one of the joint members. The pipe joint according to claim 1, further comprising an insulating layer that insulates the pipe joint from the pipe joint.