JP2001254879A - Insertion type resin pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems of a conventional insertion type resin pipe joint that a strong operation force is required to insert a resin pipe and a locking ring vertically and greatly scratches the resin pipe and excessively bites into it. SOLUTION: When an end part of the resin pipe P is inserted into a joint main body 1, a metallic locking ring 2B is pushed and expanded to obtain an initial biting condition in which a biting tooth 11 bites an outer peripheral face of the resin pipe P. Since an inside diameter of a locking ring 2A made of resin is set to be equal to or larger than an outside diameter of the resin pipe P, an operation force required for inserting the resin pipe P is merely a small force required for pushing and expanding the metallic locking ring 2B. When the resin pipe P moves in the direction of pulling-out, the locking ring 2A made of resin is pressed from the back by the metallic locking ring 2B biting the resin pipe P initially and is pressed against a tapered face 8, its diameter is reduced, and it is deformed. Its biting tooth 10 bites the outer peripheral face of the resin pipe P to prevent pulling-out of the resin pipe P.

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 resin pipe joint used for connecting resin pipes for piping such as gas and water distribution.

[0002]

2. Description of the Related Art Generally, a plug-in type resin pipe joint of this type has a socket into which an end of a resin pipe is inserted at an axial end of a tubular joint body, and an outer periphery of an inner periphery of the socket. A tapered tapered surface is formed, and a metal retaining ring that is deformable in diameter and that is deformable in diameter is incorporated in the receptacle. Biting teeth are provided on the inner periphery of the retaining ring. Then, when the end of the resin pipe is inserted into the inside of the joint body from the receiving port,
The retaining ring is pushed out and expanded by the resin tube and slightly bites into the outer peripheral surface of the resin tube, that is, is fitted outside in the initial bite state. When the resin pipe moves in the withdrawal direction in this connection state, the retaining ring that moves together with the resin pipe is pressed against the tapered surface of the joint body to reduce its diameter, and the outer peripheral surface of the resin pipe accompanies this diameter reduction. And the resin tube is prevented from being pulled out.

[0003]

However, in the above-mentioned plug-in type resin pipe joint which incorporates only a metal retaining ring as a retaining ring having a biting tooth, one of the retaining rings has an initial bite into the resin pipe. It is necessary to make the two actions work with the actual bite that goes deeper than the initial bite. For this reason, the inner diameter of the retaining ring is set smaller than the outer diameter of the resin pipe.However, in this setting, it is necessary to consider that the bite teeth can fully penetrate deeper than the initial bite. The inner diameter of the retaining ring must be set smaller than the size required for initial bite. However, in this case, since the degree of making the inner diameter of the retaining ring smaller than the outer diameter of the resin pipe becomes larger, when the outer diameter of the resin pipe reaches about 100A, the pushing force into the joint body is reduced by the expanding force of the retaining ring. Due to the dispersion, a large pushing operation force of the resin pipe is required, and the workability is reduced. In addition, when the resin tube is inserted, a longitudinal scratch is easily formed on the outer peripheral surface of the resin tube due to a scratch on the tooth tip of the biting tooth of the retaining ring, causing fluid leakage in the resin tube, and the retaining ring is made of resin. When moving in the withdrawal direction together with the pipe, the tapering surface of the joint body undergoes a diameter reduction action, and the biting teeth tend to bite deeper into the resin pipe. There is a possibility that.

SUMMARY OF THE INVENTION The object of the present invention is to solve such a problem. By using a retaining means that uses both a metal retaining ring and a resin retaining ring, the joint body is made of resin. It is an object of the present invention to provide a plug-in type resin pipe joint which facilitates insertion of a pipe, and which can prevent deep vertical damage to a resin pipe and an excessive bite problem while securing a pull-out preventing force.

[0005]

According to the present invention, there is provided a cylindrical joint main body having a receiving port into which an end of a resin pipe is inserted at an axial end thereof, and an inner peripheral portion of the receiving port. A plug-in type resin pipe joint in which a tapered surface is formed, and a retaining ring capable of expanding and contracting in diameter to be engaged with an outer peripheral surface of an end portion of the resin pipe is incorporated in the socket; The retaining ring comprises a first resin retaining ring, and a second metal retaining ring arranged side by side on the inner side of the resin retaining ring. The inner diameter of the tooth is set to be equal to or larger than the outer diameter of the resin tube, and the taper is moved when the taper moves together with the resin tube in the withdrawal direction. It is formed so as to be pressed against the surface and deformed to reduce the diameter. Because the ring has teeth bite into the inner periphery thereof, and it has the characteristics that the biting of the inner diameter is set smaller than the outer diameter of the resin pipe.

[0006]

When connecting the resin tube, when the end of the resin tube is inserted from the socket, the second metal retaining ring is pushed out by the end of the tube, and the biting teeth are cut into the outer peripheral surface of the resin tube. An initial bite state of getting stuck is obtained. At this time, the first
Since the inner diameter of the resin stopper ring is set to be equal to or larger than the outer diameter of the resin tube, the operation force required for inserting the resin tube is small enough to push and expand the metal stopper ring.

When the resin pipe moves in the withdrawal direction in this connection state, the metal stopper ring which is initially digging into the resin pipe moves in the same direction together with the resin pipe, and the metal stopper ring makes the resin stopper ring. The retaining ring is pushed back and pressed against the taper surface. The resin retaining ring is reduced in diameter as it is pressed against the taper surface, and its biting teeth bite into the outer peripheral surface of the resin tube. The penetration of the resin stopper ring prevents the resin tube from being pulled out. In other words, the metal retaining ring plays the role of initial pushing into the resin tube and the pushing action of the resin retaining ring, and the resin retaining ring plays the role of preventing the resin tube from being pulled out.

As described above, by making the first resin retaining ring and the second metal retaining ring share their respective functions, the inner diameter of the metal retaining ring is only required for the initial bite. Therefore, the inner diameter of the metal retaining ring needs to be smaller than that of the metal retaining ring that requires both the functions of the initial bite and the full bite. Deep vertical wounds and excessive bite problems can be eliminated.
The bite teeth of the resin retaining ring are less likely to crack the resin tube than those made of metal.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a plug-in type resin pipe joint according to the present invention will be described with reference to the drawings. 1 is a partially cutaway sectional view of a state before the resin pipe is inserted, FIG. 2 is a partially cutaway sectional view of the state where the resin pipe is inserted deepest, and FIG. 3 is moved in the withdrawal direction after the resin pipe is inserted. FIG. 4 is a partially cutaway sectional view showing a state in the middle of the process, and FIG.

The plug-in type resin pipe joint shown in FIG. 1 comprises a metal joint body 1, a retaining ring 2 and a seal packing 3.
The retaining ring 2 includes a first resin retaining ring 2A and a second metal retaining ring 2B. A taper 12 for facilitating insertion into the joint body 1 is attached to a terminal corner of an end of the resin pipe P inserted into the joint body 1, and a stiffener 1 is provided on an inner periphery of the end of the resin pipe P.
3 is fitted.

The metal joint body 1 is made of ductile cast iron formed in a cylindrical shape, and has openings 4 at both ends in the axial direction into which ends of a resin pipe P are inserted (in FIG. 1). Only the socket 4 at one end is shown), a pipe end stopper 5 is provided near the center in the axial direction so as to narrow the portion, and a pipe end stopper is provided between the socket 4 and the pipe end stopper 5. The first and second inward flanges 6 and 7 having an inner diameter larger than the inner diameter of the fifth flange 5 are formed. A tapered tapered surface 8 is formed on the inner periphery of the receiving port 4, and an inner peripheral surface 9 between the maximum inner diameter portion of the tapered surface 8 and the first flange 6 is an axis. It is formed on a plane parallel to the direction.

Thus, the seal packing 3 is fitted between the first and second inward flanges 6 and 7 in the joint body 1. The seal packing 3 is made of a rubber ring, and has a thin annular fold 3a formed on the inner periphery of the seal ring toward the inside in the axial direction. A first resin retaining ring 2 </ b> A is incorporated inside the socket 4 of the joint body 1, and a second metal stopper ring is provided between the resin retaining ring 2 </ b> A and the first inward flange 6. The retaining ring 2B is incorporated. The first resin retaining ring 2A is formed of a resin having a higher hardness than the material of the resin tube P and is formed in a quadrangular cross section so as to be freely deformable, and has a plurality of substantially triangular bite teeth 10 having a small cross section on its inner periphery. , Over the circumferential direction. The inner diameter of the biting teeth 10 is set to be equal to or larger than the outer diameter of the resin tube P.

The second metal retaining ring 2B is made of stainless steel or the like and has a substantially circular cross section and is capable of expanding and contracting.
A biting tooth 11 having a substantially triangular cross section is provided on the inner circumference thereof in the circumferential direction. In the bite, the inner diameter of 11 is set smaller than the outer diameter of the resin pipe P. The outer diameter of the metal retaining ring 2B is set smaller than the inner diameter of the inner peripheral surface 9 of the joint main body 1, and the outer diameter of the metal retaining ring 2B and the inner peripheral surface 9 of the joint main body 1 A gap S is formed to secure a diameter expansion allowance that allows the metal retaining ring 2B to be deformed. The metal retaining ring 2B is held at a fixed position between the first inward flange 6 and the resin retaining ring 2A.

Now, in order to connect the resin pipe P with the plug-in type resin pipe joint having the above structure, the end of the resin pipe P is inserted into the joint body 1 through the receiving port 4, and at this time, the pipe end is connected to the pipe end. It is inserted until it hits the stopper part 5. This allows
As shown in FIG. 2, an annular fold 3a of the seal packing 3 is in close contact with the outer peripheral surface of the end portion of the resin pipe P.
Of the joint body 1 and the outer periphery of the end of the resin pipe P are sealed so as to maintain waterproofness and airtightness.

At this time, the insertion of the end of the resin pipe P causes the second metal retaining ring 2B to be pushed and expanded against the elasticity to expand and deform, and the biting teeth 11 are deformed by the elastic restoring force. The bite engages with the outer peripheral surface of the end of P. At this time,
Since the metal retaining ring 2B is sandwiched between the first inward flange 6 and the resin retaining ring 2A and held at a fixed position, the metal retaining ring 2B may be inclined obliquely in the joint body 1. The resin tube P can be inserted without any trouble. Since the inner diameter of the first resin retaining ring 2A is set to be equal to or larger than the outer diameter of the resin pipe P, the operating force required for inserting the resin pipe P is only to push and expand the metal retaining ring 2B. Therefore, the resin tube P can be easily inserted.

As shown in FIG. 3, when the resin pipe P is pulled in the withdrawing direction a, the metal stopper ring 2B that initially bites into the resin pipe P moves together with the resin pipe P in the same direction. The resin retaining ring 2A is pushed back by the retaining ring 2B and pressed against the taper surface 8, and is further strongly pressed as shown in FIG.
When the force in the diameter-reducing direction is strongly received by the outer surface 8, the diameter is greatly reduced and the biting teeth 10 bite into and engage with the outer peripheral surface of the resin pipe P. The resin stopper ring 2A can reliably prevent the end of the resin tube P from coming out of the receiving port 4 due to the bite of the resin stopper ring 2A.
Further, there is no possibility of cracking the resin pipe P.

As shown in FIG. 1, instead of attaching a taper 12 for facilitating insertion into the joint main body 1 as shown in FIG. The end of the stiffener 13 is extended outward from the end of the resin pipe P, and the extended end is folded obliquely outward. It may be abuttingly engaged with the end of the tube P. In this case, the folded part 1
3a through a taper 14 formed on the outer periphery of the joint body 3a.
Can be easily plugged in. It should be noted that the tubular joint body 1 may be formed by pressing a metal pipe such as a steel pipe instead of the ductile cast iron.

[0018]

According to the present invention, there is provided a simple means that employs a retaining means in which a metal retaining ring and a resin retaining ring each having individually bite teeth are used in combination.
There is an advantage that the resin tube can be easily inserted into the joint body, and a problem of deep vertical scratches and excessive biting into the resin tube can be eliminated while securing a large pull-out preventing force.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of a state before a resin tube is inserted.

FIG. 2 is a partially cutaway sectional view of a state where a resin tube is inserted most deeply.

FIG. 3 is a partially cutaway sectional view showing a state in which the resin tube is being moved in the withdrawal direction after being inserted.

FIG. 4 is a partially cut-away sectional view of a state in which extraction of a resin tube is prevented.

FIG. 5 is a partial cross-sectional view of another example of a resin tube.

[Explanation of symbols]

 P Resin pipe 1 Joint body 2 Retaining ring 2A First resin retaining ring 2B Second metal retaining ring 4 Receptacle 6 Inward flange 8 Tapered surface 10 Biting teeth of resin retaining ring 11 Biting teeth of metal retaining ring

Claims (2)

[Claims] 1. A cylindrical joint body having a receiving port into which an end of a resin tube is inserted at an axial end thereof, and a tapered tapered surface formed on an inner periphery of the receiving port. A plug-in type resin pipe joint in which a stopper ring is formed in the receiving port, the stopper ring being capable of engaging with an outer peripheral surface of an end portion of the resin tube, the stopper ring being capable of expanding and contracting in diameter; A retaining ring made of a resin and a second ring arranged side by side inward from the resin retaining ring.
The retaining resin ring has a biting tooth on its inner periphery, and the inner diameter of the biting tooth is set to be equal to or larger than the outer diameter of the resin pipe. And formed so as to be pressed against the taper surface and deformed to reduce the diameter when moved in the withdrawing direction together with the resin pipe. The metal retaining ring has a biting tooth on its inner periphery. A plug-in type resin pipe joint, wherein an inner diameter of the bite is set smaller than an outer diameter of the resin pipe. 2. An inward flange portion is formed in an inner periphery of the joint main body in a portion deeper than the metal retaining ring, and an inward flange portion is formed between the inward flange portion and the resin retaining ring. The plug-in type resin pipe joint according to claim 1, wherein the metal retaining ring is disposed on the metal pipe.