JP2002340256A - Bell-and-spigot pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bell-and-spigot pipe joint visually confirmed on the correct insert state of a pipe, that is, whether a lock ring in the joint is engaged with a latch groove of the pipe or not, and capable of securing a pipe stopping function, and eliminating insufficient insertion of the pipe. SOLUTION: In this bell-and-spigot pipe joint, as the end part of the pipe P is once inserted from a socket 5 until it abuts on a pipe end stopper part 6, and then pulled back, the lock ring 3 is reduced in diameter by abutting on a tapered surface 10 in the socket 5 to be engaged with the latch groove 4 of the pipe P. The outer peripheral wall of the socket 5 of the joint body 1 is provided with an inspection window 11 for confirming whether the lock ring 3 engages with the latch groove 4 or not.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plug-in type pipe joint for inserting and connecting ends of pipes such as cold and hot water distribution pipes, and more particularly, to a plug-in type pipe in which it is easy to visually confirm whether the pipe is inserted properly. For joints.

[0002]

2. Description of the Related Art As this type of plug-in type pipe joint, for example, the one shown in FIG. 4 has been proposed. There, openings 5 and 5 into which the ends of the pipe P are inserted are opened at both ends in the axial direction of the cylindrical joint body 1, and the inner peripheral surface of the reception 5 is tapered in the pipe extracting direction. A taper surface 10 is formed, and a receiving port 5 is formed.
A tube end stopper 6 is provided on the inner periphery of the inner part. A lock ring 3 whose diameter can be freely enlarged and reduced, and a rubber seal ring 2 arranged on the inner side of the lock ring 3 are incorporated in the inside of the socket 5 of the joint body 1. On the other hand, on the outer surface of the end of the pipe P such as a thin stainless steel pipe connected by this pipe joint, a construction confirmation groove or a check line (hereinafter referred to as construction confirmation groove) 12 is provided, and the construction confirmation groove 12 is provided. A retaining groove 4 for engaging with the lock ring 3 is provided on the outer surface closer to the end of the end in the circumferential direction.

[0003] In this plug-in type pipe joint, as shown in FIG.
And after inserting the pipe P until the construction confirmation groove 12 enters the receptacle 5 and the end of the pipe P hits the pipe end stopper 6, the pipe P is pulled back slightly by hand as shown in FIG. During the retraction, the lock ring 3 becomes the tapered surface 1.
By engaging with the retaining groove 4 by receiving a diameter reduction action by contact with 0, the retaining function of the pipe P is ensured.

In the above-mentioned plug-in type pipe joint, when connecting the pipe P, the end of the pipe P is inserted into the socket 5 of the joint main body 1 and abutted against the pipe end stopper 6 to stop the insertion, and the connection is completed. At this time, it is checked whether the lock ring 3 is engaged with the retaining groove 4 of the pipe P in the inserted state.
The pipe P once inserted as described above is pulled back a little by hand, and the pull-back causes the construction check groove 1 as shown in FIG.
If 2 can be seen from the receiving port 5, a method of judging that the construction is good is taken.

[0005]

However, the above-mentioned plug-in type pipe joint, in which the quality of insertion of the pipe P is confirmed by the construction confirmation groove 12, lacks certainty of the confirmation. That is, when the insertion of the pipe P is stopped halfway (before the retaining groove 4 reaches the lock ring 3) as shown in FIG. 6, it is assumed that the retaining groove 4 has already been pulled back after exceeding the position of the lock ring 3. As shown in FIG. 6, there is a case where the pipe P is insufficiently inserted and the lock ring 3 is not engaged with the retaining groove 4, so that it is difficult to confirm this. When the insertion of the pipe P is stopped halfway, the pipe P is insufficiently inserted, and the lock ring 3 is not engaged with the retaining groove 4, so that the pipe P is pulled out.

An object of the present invention is to solve such a problem, and it is intended to make sure that the pipe is correctly inserted, that is, whether the lock ring in the joint is engaged with the locking groove of the pipe. It is an object of the present invention to provide a plug-in type pipe joint which can be visually confirmed, can secure a pipe retaining function, and can solve the problem of insufficient pipe insertion.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided an opening at the end of a joint body into which the end of a pipe provided with a retaining groove on the outer surface of the end in the circumferential direction is inserted. A pipe end stopper portion is provided on the inner periphery of the inner part of the mouth, and the inside of the socket is externally fitted to the end of the tube inserted into the socket,
Incorporating a lock ring capable of expanding and contracting in diameter to engage with the retaining groove at the end, and a seal ring disposed between the lock ring and the tube end stopper to closely contact the outer peripheral surface of the end of the tube. On the inner periphery of the receiving port inscribed in the lock ring, the pipe once inserted until the locking groove goes beyond the position of the lock ring moves in the withdrawal direction. In a plug-in type pipe joint provided with a tapered tapered surface in a tube withdrawing direction in which a force is applied, an outer peripheral wall of a receiving port of the joint body includes:
It is characterized in that one or two or more viewing windows are provided for visually checking whether or not the lock ring is engaged with the retaining groove.

[0008]

[Function] When connecting the pipe, insert the end of the pipe into the socket of the fitting body by hand until the locking groove goes over the lock ring and the pipe end hits the pipe end stopper. After this insertion, pull back the pipe a little. During this retraction, the lock ring, which is subjected to the diameter reducing action on the taper surface, fits into and engages with the retaining groove to ensure the function of preventing the tube from being removed. At this time, it can be easily and visually confirmed from the viewing window whether or not the lock ring is engaged with the retaining groove. At this time, if it is confirmed that the lock ring is not engaged with the lock groove and that the lock groove is located before the lock ring, it is necessary to re-insert the pipe because the pipe is insufficiently inserted. become.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partially cutaway sectional view showing a state where a pipe is inserted deepest into a plug-in fitting, and FIG. 2 is a view showing a state where the pipe is completely inserted into the plug-in fitting of FIG. It is a fragmentary sectional view.

Referring to FIG. 1, this plug-in type pipe joint has a joint main body 1, a rubber seal ring 2 having a fold-shaped piece 2a on the inner periphery, and a metal expandable and contractible having an edge 3a on the inner periphery. It is composed of a lock ring 3 and the like. A pipe P connected by this plug-in type pipe joint is made of a thin stainless steel pipe or the like, and has a retaining groove 4 provided in an outer surface near an end thereof in a circumferential direction.

The joint body 1 is formed in a cylindrical shape, and has openings 5 and 5 into which ends of the pipe P are inserted at both ends in the axial direction, and the pipe P is formed in the inner periphery near the center in the axial direction. An annular pipe end stopper portion 6 having an inner diameter smaller than the outer diameter is provided, and a seal ring accommodating groove 7 is formed on the inner periphery of a portion located in the tube withdrawal direction from the tube end stopper portion 6. 7
Further, a groove 9 for accommodating a lock ring is formed on the inner periphery of a portion located in the tube withdrawing direction via an annular wall 8.
A tapered tapered surface 10 is formed on the inner peripheral surface of the tube in the direction in which the tube is pulled out. On the outer peripheral wall forming the tapered surface 10 of the socket 5 of the joint body 1, one or two or more (see the illustrated example) for visually checking whether or not the lock ring 3 is engaged with the retaining groove 4. In this case, two viewing windows 11 are provided. The seal ring 2 is provided in the groove 7 for accommodating the seal ring of the joint body 1, and the lock ring 3 is provided in the groove 9 for accommodating the lock ring.
Are fitted respectively.

In order to connect the pipe P in the plug-in type pipe joint having the above structure, as shown in FIG.
The end of the pipe P is inserted by hand until the locking groove 4 gets over the position of the lock ring 3 and the end of the pipe P hits the pipe end stopper 6, and after this insertion, the pipe P is inserted as shown in FIG. When pulled back, the lock ring 3 subjected to the diameter reducing action on the taper surface 10 during this retraction fits into and engages with the retaining groove 4 to secure the function of preventing the pipe P from being pulled out. At the same time that the pipe P is prevented from being pulled out, the seal ring 2 comes into close contact with the outer peripheral surface of the end of the pipe P in a compressed state, so that the seal between the inner peripheral surface of the receiving port 5 and the outer peripheral surface of the end of the pipe P is formed. The state is obtained.

At this time, whether or not the lock ring 3 is engaged with the retaining groove 13 can be surely confirmed by eyes through the viewing window 11. When the pipe P is insufficiently inserted into the joint body 1, that is, when the retaining groove 4 is located short of the lock ring 3, the insertion is insufficient.
This state can be easily confirmed by looking through the viewing window 11, and the pipe P is inserted again. In addition,
Although not shown, the end of another pipe P is similarly inserted into the socket 5 at the other end of the joint body 1.

In order to set the position of the viewing window 11 and the size of the opening, the variation within the tolerance of the pipe P and the joint body 1 is taken into consideration, and as shown in FIG. The combination of the dimension and the maximum allowable dimension of the joint body 1 and the maximum dimension of the pipe P and the joint body 1 as shown in FIG.
The position and the size of the opening are determined by verifying the position of each lock ring 3 at the time of completion of the construction in the combination of the minimum dimensions allowable.

In other words, it is easy to confirm whether the lock ring 3 is engaged with the retaining groove 4 if the size of the viewing window 11 is as large as possible, but if the size is too large, the strength of the receiving end of the joint body 1 will be strong. Therefore, the pull-out inhibiting force of the taper surface 10 may be reduced, and foreign matter such as sand may enter the joint body 1 and hinder the diameter reducing action of the lock ring 3. The joint body 1 has a shape without the annular wall 8 and the seal ring 2.
In the case of a structure in which the seal ring 2 located inside the viewing window 11 may be protruded from the viewing window 11 due to the water pressure in the joint main body 1 when the structure is housed in a state where the lock ring 3 and the lock ring 3 are in contact with each other. Occurs. Therefore,
The position and the size of the opening of the viewing window 11 need to be set to the maximum dimensions within a range where such a problem does not occur. That is, as shown in FIG. 3A, the position of the end 11a on the inner side of the viewing window 11 in the tube withdrawing direction is determined by the combination of the minimum size of the pipe P and the maximum size of the joint body 1. After the pipe P is inserted, pull back and lock ring 3
Is set to a position where the lock ring 3 and the retaining groove 4 located when engaged with can be visually recognized. Then, as shown in FIG. 3 (b), the tube insertion direction side end 11 of the inner periphery of the viewing window 11.
The position of b is a lock ring which is located when the lock ring 3 is engaged with the locking groove 4 by pulling back after inserting the pipe P in a combination of the maximum allowable dimension of the pipe P and the minimum allowable dimension of the joint body 1. 3 and the retaining groove 4 are set at positions where they can be visually recognized. The position of the viewing window 11 and the size of the opening as a result of setting the positions of the inner end 11a and the insertion end 11b of the inner circumference of the viewing window 11 in this manner are shown in FIG.
This is as shown in FIG.

By the way, even if the pipe P is further strongly pulled in the withdrawal direction due to an earthquake or the like after the construction, the outer peripheral surface of the lock ring 3 moving in the same direction together with the pipe P is formed by the tapered surface 10. Since the lock ring 3 is further reduced in diameter and the bite into the retaining groove 4 is increased, it is possible to reliably prevent the end of the pipe P from coming out of the receiving port 5.

[0017]

According to the present invention, it is possible to visually confirm whether or not the retaining groove of the pipe is engaged with the lock ring from the viewing window, so that the retaining function of the pipe can be secured. ,
There is an advantage that the problem of insufficient insertion of the pipe can be solved.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of a state where a pipe is inserted deepest into a plug-in type pipe joint.

FIG. 2 is a cross-sectional view showing a state where the pipe has been inserted into the plug-in type pipe joint so that the pipe is not stopped.

FIGS. 3 (a), (b) and (c) are explanatory views for setting the positioning of a viewing window of a plug-in type pipe joint.

FIG. 4 is a partially cutaway sectional view showing a state where a pipe is inserted deepest into a conventional plug-in type pipe joint.

FIG. 5 is a partial cross-sectional view showing a state when the pipe has been inserted into the plug-in type pipe joint shown in FIG.

FIG. 6 is a partial cross-sectional view showing a state where the pipe is insufficiently inserted into the plug-in pipe of FIG. 4;

[Explanation of symbols]

 P pipe 1 Fitting body 2 Seal ring 3 Lock ring 4 Retaining groove 5 Receptacle 6 Pipe end stopper 10 Tape surface 11 Viewing window

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideki Hatayama 1 day at 153 Taji Yonemachi, Kishiwada City, Osaka Prefecture Inside of Steel Pipe Fitting Co., Ltd. (72) Inventor Masami Nakajima 1 day at 153 Taji Yonemachi, Kishiwada City, Osaka Prefecture F-term (reference) 3H015 FA01

Claims (1)

[Claims] An opening is formed at an end of a joint main body, into which the end of a pipe provided with a retaining groove on an outer surface of the end in a circumferential direction is inserted. An end stopper portion is provided, and inside the socket, a lock ring that is fitted to the end of the pipe inserted into the socket and that can freely expand and contract to engage with the retaining groove at the end. A seal ring disposed between the lock ring and the pipe end stopper portion and in close contact with the outer peripheral surface of the end of the pipe. As the pipe inserted into the lock ring moves in the pull-out direction until the retaining groove exceeds the position of the lock ring, a tapered tapered surface in the pipe pull-out direction for applying a force in the diameter reducing direction to the lock ring is applied. In the plug-in type pipe joint provided, a socket of the joint body is provided. The peripheral wall, bayonet fitting, characterized in that one or two or more viewing windows which locking ring is visible whether engaged with the retaining groove.