JP2004232692A - Spigot type pipe fitting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spigot type pipe fitting capable of being embodied in a relatively simple structure at a low cost by introducing a colletless system. <P>SOLUTION: The body 1 of this pipe fitting has a dual cylinder construction, an inner 5 and an outer 6, at its one end in the axial direction, wherein the inner cylinder 5 is formed in a single piece with the body 1, and the outer cylinder 6 is formed separately from the body 1 and coupled with the body 1 in such a way that a pipe inserting gap 15 is generated in the area with respect to the periphery of the inner cylinder 5. A seal ring groove 16 is formed at the periphery of the inner cylinder 5, and a resilient seal ring 2 is fitted in the groove 16. The outer cylinder 6 is furnished internally with a slipoff preventive ring 3 having bite-in teeth 11 deformable diametrically in expansion or contraction and biting into the peripheral surface of a pipe P. Between that position on the periphery of the inner cylinder 5 outside in the axial direction more than the resilient seal ring 2 and that position on the inside surface of the outer cylinder 6 inside in the axial direction more than the slipoff preventive ring 3, a tapered ring 4 furnished at the inside surface with a taper 17 as spreading forward is fitted in such a way when pushed by one end of the pipe P, it moves inward in the axial direction while its forefront is directed to the innermost of the pipe inserting gap 15. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a plug-in type pipe joint used for hot water supply / water supply pipes and the like, in which one end of a pipe can be easily and quickly inserted and connected in a sealed shape and a retaining shape.
[0002]
[Prior art]
As a plug-in type pipe joint of this kind, a joint body in which an elastic seal ring that is in close contact with the outer peripheral surface of a pipe to be inserted and a collet integrally formed with a biting tooth that bites into the outer peripheral surface of the pipe are incorporated. (For example, see Patent Document 1). In addition, an elastic seal ring and a collet that are in close contact with the outer peripheral surface of the pipe to be inserted are incorporated into the joint body, but a lock ring having a claw that cuts into the outer peripheral surface of the pipe is formed separately from the collet and incorporated. There are also some (for example, see Patent Document 2).
[0003]
[Patent Document 1]
JP-A-11-2377 [Patent Document 2]
Japanese Patent Application Laid-Open No. H11-118081
[Problems to be solved by the invention]
However, the plug-in type pipe joint incorporating the collet increases the number of assembling steps, complicates the structure, and increases the cost.
An object of the present invention is to solve such a problem, and it is an object of the present invention to provide a plug-in type pipe joint which is relatively simple in structure and inexpensive by using a colletless method.
[0005]
[Means for Solving the Problems]
The plug-in type pipe joint of the present invention includes an elastic seal ring, a retaining ring, and a tapered ring on the joint body. The joint body has an inner / outer double cylinder at one end in the axial direction, the inner cylinder is formed integrally with the joint body, and the outer cylinder is formed separately from the joint body. Is connected to the joint body so as to form a pipe insertion gap with the outer periphery of the joint. A seal ring groove is formed on the outer periphery of the inner cylindrical body, and the elastic seal ring having an outer diameter smaller than the outer diameter of the pipe inserted into the pipe insertion gap and larger than the inner diameter in the seal ring groove. Is fitted. The retaining ring is provided inside the outer cylindrical body, and has an inner diameter portion provided with a biting tooth which is capable of expanding and contracting in a manner to bite into the outer peripheral surface of the tube. The tapered ring has a forwardly expanding taper at the inner diameter thereof, and the tapered ring is located on the outer periphery of the inner cylinder body in an axially outer region than the elastic seal ring, and on the inner periphery of the outer cylinder body. The front end is fitted between the retaining ring and the axially inward portion so as to move inward in the axial direction toward the inside of the tube insertion gap while being pressed at one end of the tube. Things.
[0006]
As one preferred embodiment, in the plug-in type pipe joint according to the present invention, the retaining ring is provided with resilient bite teeth which bite into the outer peripheral surface of the pipe while being pushed and opened by insertion of the pipe, and the outer cylindrical body is provided with: The retaining ring can be formed by insert molding the resin into the outer cylinder. The retaining ring is made of a wire and is housed in a concave portion on the inner periphery of the outer cylindrical body. It is also possible to form a constricted tapered pressing surface for applying a force.
[0007]
According to the plug-in type pipe joint having the above configuration, as one end of the pipe is inserted into the pipe insertion gap, the tapered ring is pushed inward in the axial direction toward the inside of the pipe insertion gap, and the tapered ring is inserted. Since the elastic seal ring is pressed into the seal ring groove of the inner cylinder body while being compressed by the taper of the ring, the pipe collides with the elastic seal ring even if the inner circumference of one end of the pipe is not chamfered in advance. It is inserted smoothly without.
[0008]
When one end of the pipe is inserted into the pipe insertion gap of the joint body, the space between the inner peripheral surface of the pipe and the outer peripheral surface of the inner cylindrical body is sealed by an elastic seal ring, and the biting teeth of the retaining ring are attached to the outer periphery of the pipe. Dig into the surface. This can prevent the pipe from coming out of the pipe insertion gap of the joint body.
[0009]
If the retaining ring is integrated into the outer cylinder by insert molding in advance, the retaining ring can be assembled at the same time as the outer cylinder is joined to the joint body, so that the retaining ring is cumbersome. The number of assembling steps can be omitted.
[0010]
The retaining ring is made of a wire and is housed in a concave portion on the inner periphery of the outer cylinder. The inner periphery of the concave portion acts on the retaining ring in such a manner that a force in the radial direction acts on the retaining ring when the tube moves in the exit direction. If a tapered pressing surface is formed, when the tube is pulled in the withdrawal direction, the outer peripheral surface of the retaining ring that moves in the same direction with the tube comes into contact with the pressing surface of the outer cylinder, and the retaining ring The diameter is reduced, and the bite of the biting teeth into the outer peripheral surface of the tube is increased, so that a reliable pull-out preventing force of the tube is obtained.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
A preferred embodiment of the present invention will be described with reference to the drawings. 1 is a partially cutaway sectional view of a plug-in type pipe joint according to a first embodiment, FIG. 2 is a front view of a retaining ring incorporated in the plug-in type pipe joint, and FIG. 3 is a cross-sectional view taken along line AA in FIG. FIG. 4 is a partially cutaway sectional view of the state where the pipe is inserted most deeply.
[0012]
(First embodiment)
In FIG. 1, the plug-in type pipe joint includes a joint body 1, an elastic seal ring 2, a retaining ring 3, and a tapered ring 4.
[0013]
The joint main body 1 is formed in a tubular shape from a bronze casting or the like, and has a structure having inner and outer double cylinders 5 and 6 at one axial end thereof. Among them, the inner cylinder 5 is formed integrally with the joint body 1, while the outer cylinder 6 is resin-molded separately from the joint body 1, and is provided on one end inner periphery and on the outer periphery of the joint body 1. A female screw 8 screwed into the male screw 7 is provided. A male screw 9 is cut on the outer periphery of the other end of the joint body 1 in the axial direction, and a female tap with a female screw (not shown) or an elbow is screwed into the male screw 9.
[0014]
The retaining ring 3 is a stainless steel product. As shown in FIGS. 2 and 3, the split grooves 10 are provided at equal intervals in the circumferential direction at the inner diameter of the dish-shaped cross section to have elasticity. The teeth 11 are arranged. The retaining ring 3 is insert-molded in the outer cylinder 6. At the time of this insert molding, for example, a spacer 13 that is resin-molded in a form in which the whole is cylindrical and a taper 12 for biting teeth escape is provided on the inner periphery of one end is prepared, and the end face of one end of the spacer 13 is prepared. The retaining ring 3 is superimposed on the outer ring 6 and the retainer 14 is held on the outside of the retaining ring 3 in a mold. And insert-molded integrally on the inner circumference of. As the resin material of the outer cylinder 6 and the spacer 13, for example, a transparent resin having excellent heat resistance such as PPSU (polyphenylsulfone), polycarbonate, and ABS resin is used.
[0015]
At the time of the insert molding, the outer cylindrical body 6 having the taper 12 for relieving bite teeth can be easily injection-molded with a simple mold structure by using the spacer 13, but it is not necessarily required to use the spacer 13 to prevent the outer cylinder 6 from coming off. The ring 3 can be insert-molded into the outer cylinder 6. Further, the retainer 14 is not always necessary.
[0016]
The outer cylindrical body 6 integrally formed with the retaining ring 3 in this manner is formed by screwing the female screw 8 at one end thereof into the male screw 7 of the joint main body 1 to connect the outer cylindrical body 6 to the outer periphery of the inner cylindrical body 5. A tube insertion gap 15 is formed between them.
[0017]
One or more (two in the illustrated example) seal ring grooves 16 are provided on the outer periphery of the inner cylindrical body 5, and a resin made of a resin such as a polybutene pipe inserted into the pipe insertion gap 15 is provided in the seal ring grooves 16. An elastic seal ring 2 made of an O-ring or the like having an outer diameter smaller than the outer diameter of the tube P and larger than the inner diameter thereof and closely contacting the inner peripheral surface of the tube P is fitted. This fitting can be easily performed by performing the fitting before connecting the outer cylinder body 6 to the joint body 1. The outer cylinder 6 is connected to the joint body 1 after the elastic seal ring 2 is fitted.
[0018]
The tapered ring 4 is a resin molded product of nylon or the like, and has a forwardly expanding taper 17 gradually narrowing from the front end to the rear at the inner diameter. The tapered ring 4 is incorporated so as to be located at a position axially outward of the elastic seal ring 2 on the outer periphery of the inner cylindrical body 5.
[0019]
Next, the usage of the plug-in type pipe joint having the above configuration will be described. In on-site construction, first, the pipe P is cut to a required length. One end of the cut pipe P is inserted into the pipe insertion gap 15 between the inner and outer cylinders 5 and 6 as shown in FIG. The bite teeth 11 are inserted while being pushed open in the direction of the taper 12. With this insertion, the tapered ring 4 is pushed into the inside of the pipe insertion gap 15 at one end of the pipe P, and the taper 17 of the tapered ring 4 projects from the seal ring groove 16 of the inner cylinder 5. The ring 2 comes into contact with the outer peripheral portion of the ring 2, compresses the ring 2, and pushes the ring 2 into the seal ring groove 16 to pass through. Therefore, the pipe P can be inserted smoothly without hitting the elastic seal ring 2 without chamfering the inner circumference of one end of the pipe P in advance.
[0020]
When the pipe P is inserted into the joint main body 1 to a predetermined depth, the elastic seal ring 2 comes into close contact with the inner peripheral surface of the pipe P in a compressed state, and the elastic seal ring 2 allows the inner peripheral surface of the pipe P to contact the inner peripheral surface. The gap between the outer peripheral surface of the tubular body 5 and the outer peripheral surface of the tube P is sealed, and the retaining state of the pipe P in which the biting teeth 11 of the retaining ring 3 bite into the outer peripheral surface of the pipe P is obtained.
[0021]
When the pipe P is pulled in the withdrawal direction, the inner diameter of the retaining ring 3 that moves in the same direction together with the pipe P is elastically deformed in a reduced-diameter manner, so that the bite teeth 11 penetrate the outer peripheral surface of the pipe P. The pipe P is reliably prevented from coming out of the pipe insertion gap 15.
[0022]
When the pipe P is to be removed from the joint body 1 from the insertion connection state of the pipe P, the tightening of the outer cylinder 6 with the male screw 7 of the joint body 1 is loosened and the outer cylinder 6 is removed from the joint body 1 by removing the pipe P from the joint body 1. Can be removed from the joint body 1.
[0023]
(Second embodiment)
5 and 6 show a second embodiment. In this embodiment, the retaining ring 3 and how to attach the retaining ring 3 to the outer cylinder 6 are different from those of the first embodiment, and the other configuration is the same as that of the first embodiment. , The same members and the same elements have the same reference characters allotted, and description thereof will not be repeated. The retaining ring 3 is made of a wire material such as stainless steel, and is provided with a biting tooth 11 that bites into the outer peripheral surface of the pipe P inserted into the pipe insertion gap 15 on the inner periphery thereof. A part of the circumference is cut off, and the entire retaining ring 3 is formed so as to be able to expand and contract the diameter.
[0024]
The retaining ring 3 is accommodated in a concave portion 18 provided on the inner periphery of the outer cylindrical body 6, and a force in the radial direction is applied to the retaining ring 3 on the inner peripheral surface of the concave portion 18 on the outer side in the axial direction. The outer constricted tapered pressing surface 19 to be operated is formed in a shape constricted toward the open end of the outer cylindrical body 6. As means for providing the concave portion 18 on the inner periphery of the outer cylindrical body 6, a spacer 20 separate from the outer cylindrical body 6 is fitted inside the outer cylindrical body 6, and the axially outer end face of the spacer 20 is pressed against the outer cylindrical body 6. The concave portion 18 is formed between the concave portion 18 and the surface 19. Alternatively, the concave portion 18 can be formed simultaneously with the molding of the outer cylindrical body 6 without using such a spacer 20.
[0025]
In the plug-in type pipe joint constructed as described above, one end of the pipe P is inserted into the pipe insertion gap 15 between the inner and outer cylindrical bodies 5 and 6, as shown in FIG. At this time, one end of the pipe P is inserted while pushing the retaining ring 3 open. With this insertion, the tapered ring 4 is pushed into the inside of the pipe insertion gap 15 at one end of the pipe P, and the taper 17 of the tapered ring 4 projects from the seal ring groove 16 of the inner cylinder 5. The ring 2 comes into contact with the outer peripheral portion of the ring 2, compresses the ring 2, and pushes the ring 2 into the seal ring groove 16 to pass through.
[0026]
When the pipe P is inserted into the joint main body 1 to a predetermined depth, the elastic seal ring 2 comes into close contact with the inner peripheral surface of the pipe P in a compressed state, and the elastic seal ring 2 allows the inner peripheral surface of the pipe P to contact the inner peripheral surface. The gap between the outer peripheral surface of the tubular body 5 and the outer peripheral surface of the tube P is sealed, and the retaining state of the pipe P in which the biting teeth 11 of the retaining ring 3 bite into the outer peripheral surface of the pipe P is obtained.
[0027]
When the pipe P is pulled in the withdrawal direction, the outer peripheral surface of the retaining ring 3 that moves in the same direction together with the pipe P comes into contact with the pressing surface 19 of the outer cylindrical body 6, whereby the retaining ring 3 is reduced in diameter, The bite teeth 11 bite into the outer peripheral surface of the pipe P increases. As described above, the outer peripheral surface of the retaining ring 3 comes into contact with the pressing surface 19 of the outer cylindrical body 6 and the biting teeth 11 of the retaining ring 3 bite into the outer peripheral surface of the pipe P. Is more reliably prevented from coming off.
It is possible to remove the outer cylinder 6 and the pipe P from the joint body 1 by loosening the tightening of the outer cylinder 6 with the male screw 7 of the joint body 1 from the insertion connection state of the pipe P as in the case of the first embodiment. The same is true.
[0028]
The present invention can be similarly applied to the case where the joint main body 1 is an elbow, a T-type, or the like in addition to the socket type shown in the illustrated example.
[0029]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, one end part of a pipe | tube can be easily and quickly inserted and connected like a seal shape and a retaining shape, and since it has a structure without a collet, the structure and assembly are simplified, and the cost is reduced. Things.
[Brief description of the drawings]
FIG. 1 is a partially cutaway sectional view of a plug-in type pipe joint according to a first embodiment.
FIG. 2 is a front view of a retaining ring incorporated in the plug-in type pipe joint of FIG.
FIG. 3 is a sectional view taken along line AA in FIG. 2;
FIG. 4 is a partially cutaway sectional view of the pipe with the pipe inserted most deeply.
FIG. 5 is a partially cutaway sectional view of a plug-in type pipe joint according to the second embodiment shown in FIG. 1;
6 is a partially cutaway sectional view of the plug-in type pipe joint shown in FIG. 5, corresponding to FIG. 4;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Joint main body 2 Elastic seal ring 3 Retaining ring 4 Taper ring 5 Inner cylinder 6 Outer cylinder 11 Biting teeth 15 Pipe insertion gap 16 Seal ring groove 17 Taper of tapered ring 18 Recess 19 Pressing surface

Claims (3)

The joint body has an elastic seal ring, retaining ring, and tapered ring,
The joint body has an inner / outer double cylinder at one end in the axial direction, the inner cylinder is formed integrally with the joint body, and the outer cylinder is formed separately from the joint body. Is connected to the joint body so as to form a pipe insertion gap with the outer periphery of the
A seal ring groove is formed on the outer periphery of the inner cylindrical body, and the elastic seal ring having an outer diameter smaller than the outer diameter of the pipe inserted into the pipe insertion gap and larger than the inner diameter in the seal ring groove. Is fitted,
The retaining ring is provided inside the outer cylindrical body, and has an inner diameter portion provided with a biting tooth that is capable of expanding and contracting to deform into the outer peripheral surface of the tube,
The tapered ring has a forwardly expanding taper at the inner diameter thereof, and the tapered ring is located on the outer periphery of the inner cylinder body in an axially outer region than the elastic seal ring, and on the inner periphery of the outer cylinder body. The front end is fitted between the retaining ring and the axially inward portion so as to move inward in the axial direction toward the inside of the tube insertion gap while being pressed at one end of the tube. A plug-in type pipe joint, characterized in that: The retaining ring is provided with a biting tooth having elasticity to bite into the outer peripheral surface of the tube while being pushed open by insertion of the tube, and the outer cylinder is formed of a resin material, and the outer cylinder is The plug-in type pipe joint according to claim 1, wherein the retaining ring is insert-molded. The retaining ring is made of a wire and is housed in a concave portion on the inner periphery of the outer cylindrical body. The inner peripheral portion of the concave portion has a force in a radially decreasing direction applied to the retaining ring when the tube moves in the exit direction. 2. The plug-in type pipe joint according to claim 1, wherein an external constriction tapered pressing surface for acting is formed.

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