JPH09189385A - Pipe joint and grip ring for pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint to enlarge an allowable region of a pipe diameter in simple structure and enhance the fixing strength and a grip ring for the pipe joint. SOLUTION: A cylindrical end part of a roughly cylindrical grip ring 3 having elasticity is fit and inserted into an insertion hole 5 installing an O ring 9 on an inner circumference of a connecting pipe part 6 of both end parts of a roughly cylindrical joint main body 2. A pipe 7 to fit and insert a coupling nut 4 is inserted into the grip ring 3 while getting over a click part 17 provided on an inner circumferential surface by a guide inclined surface 18 and it is fit on the O ring 9. A female screw part 20 of an inner circumference on one end side of the coupling nut 4 is screwed on a male screw part 11 of an outer peripheral surface of the connecting pipe part 6. It is made contact with a tapered surface 13 an outer peripheral surface of the grip ring 3 and an end part edge and fastened on an inclined surface 21 contracted in diameter toward an end part of the coupling nut 4. The grip ring 3 is contracted in diameter as its curvature increases by a cut groove 14 along both end edges, and the click part 17 bites in an outer peripheral surface of the pipe 7 and fixes the pipe 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint for connecting and fixing pipes by screwing a coupling nut, and a grip ring for the pipe joint.

[0002]

2. Description of the Related Art Conventionally, for example, a pipe joint is known in which a coupling nut is screwed into a joint body having a grip ring shown in FIG.

In the pipe joint 41 shown in FIG. 18, a grip ring 42 formed into a substantially cylindrical shape by imparting elasticity with a synthetic resin has a tapered surface 43 on the outer peripheral surface on one end side, the diameter of which is reduced toward the one end side. have. Furthermore, this grip ring 42
Along the axial direction from one edge of the
Are provided in plurality, and the other end is formed in a thick annular shape for reinforcement. Also, on the inner peripheral surface of the grip ring 42,
A wall-shaped claw portion 45 is provided in the circumferential direction, which is not locked when the tube is inserted into the grip ring 42 and is locked when the tube is pulled out. On the other hand, the connecting pipe parts 47 at both ends of the substantially cylindrical joint body 46 are formed in a substantially cylindrical shape in which O-rings 48 are provided at both ends in the axial direction and the other end of the grip ring 42 is inserted.
Male screw parts 49 are provided on the outer peripheral surfaces of both ends. Further, the coupling nut 50 has a female screw portion 51 that is screwed into the male screw portion 49 of the connecting pipe portion 47 on the inner peripheral surface on the one end side, and the grip ring on the inner peripheral surface on the other end side toward the other end side. It has an inclined surface 52 whose diameter is smaller than the outer diameter of 42.

The ring-shaped other end of the grip ring 42 is fitted into both ends of a substantially cylindrical connecting pipe portion 47 provided with an O-ring 48 in advance, and connecting pipes are connected to the connecting pipe portion 47, respectively. The coupling nuts 50, which are inserted into the grip rings 42 exposed from the ends, respectively, and which are previously inserted into the pipes, are screwed into the connecting pipe portions 47. Due to this screwing, the inclined surface 52 of the coupling nut 50 grips the grip ring.
The pipes are connected by reducing the diameter of the end portion of the cut groove 44 of the cutout 42 against elasticity and pressing the claw portion 45 of the inner peripheral surface against the outer peripheral surface of the pipe.

[0005]

However, in the conventional pipe joint 41 shown in FIG. 18, the grip ring 42 is used.
Since one end of the grip ring 42 is formed in an annular shape by screwing the coupling nut 50, the diameter of the end on the side where the cut groove 44 is formed is reduced. Since the entire diameter does not decrease, the claws 45 that are crimped to the outer peripheral surface of the pipe are only the claws 45 located on the end side with the large diameter reduction, and the other claws 45 come into contact with the other claws 45 to obtain sufficient strength to fix the pipe. I can't. Further, when the coupling nut 50 is screwed, the end portion is reduced in diameter in the cut groove 44 so as to fall toward the inner peripheral side, and the curvature of the end portion which is reduced is almost unchanged, so that a part of the claw portion 45 is not changed. Since it is crimped to the outer peripheral surface of the pipe, a large fixing strength of the pipe cannot be obtained. Further, since the one end side is formed in an annular shape, the grip ring 42 having a different diameter for each pipe diameter standard is provided.
When the diameter is larger than a predetermined diameter due to the dimensional tolerance of the pipe, it cannot be inserted into the grip ring 42, and there is a problem that the manufacturing cost and product management are complicated and the construction is complicated. .

The present invention has been made in view of the above problems, and an object of the present invention is to provide a pipe joint and a grip ring for the pipe joint, which have a simple structure to increase the allowable range of the pipe diameter and increase the fixing strength. To do.

[0007]

A grip ring for a pipe joint according to claim 1 has elasticity and is formed in a substantially cylindrical shape, and an inner peripheral surface of the substantially cylindrical shape abuts an outer peripheral surface of the pipe. The outer peripheral surface is provided with claws and has a taper surface with an outer diameter that decreases toward the end on the side where the pipe is inserted. Since it is formed by notching, and the kerf is continuously provided over both edges, it is possible to expand and contract the diameter, which increases the allowable range of the diameter of the pipe to be fixed, and when expanding and contracting the diameter. Since the curvature is large throughout the axial direction, the entire claw portion provided on the inner peripheral surface is crimped to the outer peripheral surface of the tube, so that the fixing strength of the tube is increased.

A grip ring for a pipe joint according to a second aspect is the grip ring for a pipe joint according to the first aspect, wherein the kerf has a substantially wavy shape in which convex portions and concave portions are alternately arranged in the circumferential direction. Since the convex portions that are formed and are alternately located overlap each other in the axial direction, the occurrence of twist in the kerf portion is suppressed, and the allowable range of the diameter of the fixable tube is further increased.

A grip ring for a pipe joint according to a third aspect of the present invention is the grip ring for a pipe joint according to the first or second aspect, in which a thin groove recess is provided substantially along the axial direction. Since the groove recess is provided in a thin shape along the axial direction, the groove recess causes the thin portion to act like a hinge, which facilitates elastic deformation at the time of expanding and contracting the diameter, thus improving workability.

A grip ring for a pipe joint according to a fourth aspect of the present invention is the grip ring for a pipe joint according to any of the first to third aspects, in which a groove-shaped portion partially cut out along the substantially axial direction is provided. Since the groove-shaped portion is provided by cutting out a portion along the substantially axial direction, the portion of the groove-shaped portion whose axial length becomes shorter acts like a hinge and expands. Elastic deformation at the time of diameter reduction and diameter reduction is facilitated, and workability is improved.

According to a fifth aspect of the present invention, in the pipe joint according to any of the first to fourth aspects, the grip ring for the pipe joint is opened, and an insertion hole for inserting a pipe is opened, and the side of the grip ring having a large outer diameter is fitted. A joint body having a substantially cylindrical connecting pipe portion provided with an external thread portion on the outer peripheral surface, and an internal thread portion screwed to the external thread of the connecting pipe portion is provided on the inner peripheral surface at one end side, and the other end side is provided. An inclined surface that reduces the inner diameter toward the other end on the inner peripheral surface and tightens the smaller outer diameter side of the grip ring by screwing the female threaded portion onto the male threaded portion to reduce the diameter of the grip ring. With a substantially cylindrical coupling nut provided, a pipe with a larger outer diameter fitted by the tapered surface of the grip ring into the insertion hole of the connecting pipe part of the joint body, and the coupling nut is fitted in advance. The grip The coupling nut with the connecting pipe, and the inclined surface of the coupling nut tightens the grip ring against the elasticity to reduce the diameter, and the claws on the inner peripheral surface are connected to the outer periphery of the pipe. Crim the surface to secure the tube.

A pipe joint according to a sixth aspect is the pipe joint according to the fifth aspect, wherein the joint body is provided on an inner peripheral surface and has a step portion projecting inward and having an inner diameter smaller than an outer diameter of the pipe. An annular packing in which one end face in the axial direction abuts on the step portion and the other end face in the axial direction abuts the end portion on the insertion side of the pipe. While attaching the packing by abutting the end in the axial direction to the part, insert the pipe with the large outer diameter of the grip ring into the insertion hole of the connecting pipe part, and insert the coupling nut in advance. Insert into the grip ring until the end contacts the end surface of the packing, screw the coupling nut into the connecting pipe, and tighten the grip ring against the elasticity on the inclined surface of the coupling nut to reduce the diameter. Together with the tapered surface of the grip ring Go to the grip ring and the tube further fitted into the fitting body by tightening of the coupling nut, the end of the tube is crimped to the end surface of the packing, watertight can be easily obtained.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a pipe joint of the present invention will be described below with reference to the drawings.

1 and 2, 1 is a pipe joint,
The pipe joint 1 is composed of a joint body 2, a grip ring 3 and a coupling nut 4. The joint body 2 is made of, for example, a synthetic resin and is formed into a substantially cylindrical shape. The substantially cylindrical connecting pipe portions 6 and 6 are integrally provided in a substantially coaxial shape to form a substantially cylindrical shape. In addition, the joint body 2 is provided with a positioning rib 8 at an approximately central portion of the inner peripheral surface so that the inner diameter is smaller than the outer diameter of the pipe 7 to be connected. Further, a step portion 10 with which an O-ring 9 is locked is provided on an inner peripheral surface of an end portion of the connecting pipe portion 6 which is both end portions of the joint body 2.
And a male screw portion 11 is provided on the outer peripheral surface of the connecting pipe portion 6. Further, a stopper portion 12 is provided on the center side of the joint body 2 which is the proximal end side of the male screw portion 11 so as to abut the end portion of the coupling nut 4 and regulate the screwing of the coupling nut 4.

A grip ring 3 is fitted in the connecting pipe portion 6 of the joint body 2. As shown in FIGS. 1 to 5, the grip ring 3 is formed in a substantially cylindrical shape by being imparted with elasticity by a synthetic resin. Then, on the outer peripheral surface, a tapered surface whose diameter is reduced from the intermediate portion toward one end side
13 are provided.

Further, the grip ring 3 is formed with a notch 14 extending along both axial edges thereof so as to be able to be expanded and contracted in diameter. And this kerf 14
Is formed in a substantially wavy shape by alternately providing convex portions 15 and concave portions 16 in the circumferential direction of the grip ring 3. And, as shown in FIG. 3 and FIG.
The gap is about 3 mm, the axial overlap of the convex portion 15 on the one edge side of the kerf 14 and the concave portion 16 on the other edge side is about 3 mm, and when the diameter is reduced, the opposing convex portions as shown in FIG. Section
A gap of less than 1 mm is created at the top of 15 and the concave portion 16.

Furthermore, on the inner peripheral surface of the grip ring 3,
A claw portion 17 protruding in a wall shape along the circumferential direction is provided. The claw portion 17 includes a convex portion 15 and a concave portion 16 of the kerf 14.
It has a guide inclined surface 18 that is provided at a position that passes through the top of the and is inclined so that the diameter increases toward the diameter reducing direction side of the tapered surface 13.

On the other hand, the coupling nut 4 is made of a synthetic resin of the same material as that of the joint body 2 and is formed into a substantially cylindrical shape. The coupling nut portion 4 of the joint body 2 is formed on the inner peripheral surface at one end side in the axial direction. A female screw portion 20 that is screwed into the male screw portion 11 is provided. Further, on the inner peripheral surface on the other end side in the axial direction, the diameter on the other end side is reduced toward the other end side so that the opening on the other end side is smaller in diameter than the outer diameter of the grip ring 3 in the reduced diameter state. Sloped surface 21
Is provided. A plurality of ribs 22 are provided on the outer peripheral surface to prevent the coupling nut 4 from rotating and to prevent slippage.

Next, the operation of connecting the pipes 7 of the above embodiment will be described.

The O-rings 9 are preliminarily attached to the step portions 10 at both ends of the joint body 2 through the insertion holes 5, and the cylindrical end portion of the grip ring 3 on which the tapered surface 13 is not provided is attached to the O-ring. 9 are inserted into the through holes 5 so as to be pressed against the step portions 10. On the other hand, the coupling nut 4 is inserted into the pipe 7 to be connected so that the end portion of the coupling nut 4 on the female screw portion 20 side faces the end portion side of the pipe 7.

Then, the end portion of the pipe 7 through which the coupling nut 4 is inserted is inserted from the end portion of the grip ring 3 exposed from the insertion hole 5 of the connecting pipe portion 6 of the joint body 2. This pipe 7
At the time of insertion, the pipe 7 is inserted into the grip ring 3 so that the tip edge of the pipe 7 is guided by the guide inclined surface 18 of the claw portion 17 and gets over the claw portion 17. Further, when the tube 7 is inserted, the tube 7
Fits into the O-ring 9 and the tip of the tube 7 contacts the positioning rib 8.

Next, the female thread portion 20 of the coupling nut 4
Is screwed onto the male screw portion 11 of the connecting pipe portion 6. Due to this screwing, the inclined surface 21 of the coupling nut 4 comes into contact with the tapered surface 13 and the end edge of the grip ring 3 and the grip ring 3 is gradually tightened, and the grip ring 3 has a reduced diameter so as to have a large curvature. Then, the claw portion 17 is pressed and locked so as to bite into the outer peripheral surface of the pipe 7, and the pipe 7 is watertightly fixed and connected to the pipe joint 1.

Next, the operation of the above embodiment will be described.

First, when the pipe diameter is larger than the standard, when inserting the pipe 7 into the grip ring 3, the gap of the kerf 14 is opened and the grip ring 3 is inserted while expanding the diameter against elasticity. Grip ring 3 by screwing ring nut 4
Is clamped, and the claw portion 17 is crimped so as to bite into the outer peripheral surface of the tube 7 and is locked and fixed.

If the pipe diameter is smaller than the standard, after inserting it into the grip ring 3, the coupling nut 4 is screwed to tighten the grip ring 3 and reduce the diameter against the elasticity, so that the grip ring 3 is fixed. It is tightened, and the claw portion 17 is crimped so as to bite into the outer peripheral surface of the tube 7 so as to be locked and fixed.

According to the above-mentioned embodiment, since the kerf 14 having the substantially cylindrical shape having elasticity is provided with the kerfs 14 extending along both ends along the axial direction, the pipe 7 for connecting, connecting, branching and the like is formed. Even if the diameter deviates from the standard, the grip ring 3 can be elastically contracted and expanded to fix the pipe 7, so that the range of pipe diameters that can be fixed by one grip ring 3 is increased and the number of parts is reduced. The number of parts to be prepared can be reduced at the time of connecting, connecting, and branching work, and the workability can be improved.

Further, when the coupling nut 4 is tightened by the cut groove 14 extending over both end edges, a force is applied in the tangential direction of the outer peripheral surface of the grip ring 3 due to this tightening, and the overall contraction is made to increase the curvature. Since the diameter is reduced and the inner peripheral surface is reduced along the outer peripheral surface of the pipe 7, all the claw portions 17 provided on the inner peripheral surface can be crimped to the outer peripheral surface of the pipe 7 as a whole, and the fixing strength of the pipe 7 is fixed. While improving the fixing strength, the screwing strength of the coupling nut 4 can be reduced, and the pipe 7 can be firmly fixed even with a small force, and work such as connecting, connecting, and branching the pipe 7 can be performed. Can be done easily.

Further, the kerf 14 is provided with a convex portion 15 and a concave portion 16.
Formed in a substantially corrugated shape in which the
Since the tops of the convex portions 15 at the edges are overlapped with each other in the axial direction, it is possible to suppress the occurrence of twist in the kerf 14 and further increase the allowable range of the diameter of the pipe to be fixed. Further, when the grip ring 3 is reduced to the minimum diameter, the convex portion 15 and the concave portion 16 which face the kerf 14 face each other.
Since the top part of the
Since the convex portions 15 and the concave portions 16 of 14 abut on portions other than the top portions, the tightening force acting in the tangential direction can be dispersed, and damage to the grip ring 3 due to excessive tightening can be prevented.

Since the diameter can be expanded and reduced,
The mold structure can be simplified, the mold can be easily released, and the manufacturability can be improved.

Next, another embodiment of the pipe joint of the present invention will be described with reference to the drawings.

The embodiment shown in FIG. 6 is similar to that shown in FIGS.
In the embodiment shown in, the packing 25 is provided instead of the O-ring 9.

That is, the stepped portion 26 of the joint body 2 is formed so as to project inward so that the inner diameter is smaller than the outer diameter of the tube 7 into which it is inserted. The step portion 26 is abutted against the step portion 26 so that the step portion 26 is not fitted into the step portion 26.

The packing 25 is formed in an annular shape having an inner diameter substantially the same as the inner diameter of the pipe 7, one end in the axial direction is formed in a flat shape, and the outer peripheral edge at the other end in the axial direction is a circular arc notch 27. Has a cutout. The packing 25 is mounted on the inner circumference of the joint body 2 so that the side on which the cutout 27 is formed contacts the step 26.

When connecting the pipes 7, the packing 25 is inserted from the insertion hole 5 of the connecting pipe portion 6 of the joint body 2, and the axial end of the packing 25 is attached to the step 26 of the joint body 2. The packing 25 is installed in the joint body 2 by abutting against each other.
Next, the side of the grip ring 3 having a larger outer diameter is inserted from the insertion hole 5 of the connecting pipe portion 6 of the joint body 2 and the end of the grip ring 3 having a larger diameter is brought into contact with the end surface of the packing 25 to grip the grip 25. The ring 3 is mounted in the joint body 2.

After this, similarly to the embodiment shown in FIGS. 1 to 5, the pipe 7 in which the coupling nut 4 is previously inserted is inserted, and the end of the pipe 7 is on the large diameter side of the grip ring 3 of the packing 25. It is inserted into the grip ring 3 until it abuts against the end face of the abutment, and the female screw portion 20 of the coupling nut 4 is screwed into the male screw portion 11 of the connecting pipe portion 6. Due to the screwing of the coupling nut 4, the inclined surface 21 of the coupling nut 4 is similar to the embodiment shown in FIGS. 1 to 5.
However, the grip ring 3 is gradually tightened by coming into contact with the tapered surface 13 and the end edge of the grip ring 3, the grip ring 3 is reduced in diameter so as to have a large curvature, and the claw portion 17 bites into the outer peripheral surface of the pipe 7. As described above, the pipe 7 is locked by being crimped as described above, and the grip ring 3 and the pipe 7 to which the grip ring 3 is crimped are further fitted to the joint body 2 by tightening the coupling nut 4 on the tapered surface 13 of the grip ring 3. The end portions of the grip ring 3 and the pipe 7 are deformed so as to crush the packing 25 against elasticity and are pressed against the end face of the packing 25, and the pipe 7 is watertightly fixed to the pipe joint 1. Are connected.

According to this structure, in the pipe joint 1 using the O-ring 9 shown in FIGS. 1 to 5, when the pipe 7 is inserted into the O-ring 9, the pipe 7 and the O-ring 9 are fitted by friction. It is not easy to insert the pipe 7, and it is necessary to chamfer the outer peripheral edge of the end of the pipe 7 in order to improve the insertability of the pipe 7.
According to the configuration in which the end face of the pipe 7 is crimped to the end face of the packing 25 by using the packing 25 shown in FIG. 3, the pipe 7 can be easily fitted and inserted without processing the pipe 7 and the joint work of the pipe 7 can be facilitated .

In the embodiment shown in FIG. 6, the notch 27 is provided in the packing 25 for explanation.
You can do without 27. In addition, due to the notch 27, the step
Since a gap is formed between the corner portion of 26 and the packing 25, this gap serves as a clearance when elastic deformation of the packing 25 occurs, and the packing 25 is elastically deformed without damage. A wide range of axial dimensions can be adopted.

Further, as shown in FIG. 7, an annular groove 28 having a semicircular cross section may be further provided on the end surface of the packing 25 on the side where the notch 27 is provided. With this annular groove 28,
Furthermore, the packing 25 can be elastically deformed without difficulty, and the watertightness can be further improved with a simple structure.

In the embodiment shown in FIGS. 1 to 5, the embodiment shown in FIG. 6 and the embodiment shown in FIG. 7, the kerf 14 is formed on the tops of the convex portion 15 and the concave portion 16. Has been described as being formed in an arcuate wavy shape, but it may be formed in a U shape as shown in FIG. 8, a jagged shape, or a combination of a C shape and a jagged shape as shown in FIG. It can be formed in any wave shape, or can be formed linearly along the axial direction.

Further, the claw portions 17 may be formed in a staggered manner as shown in FIG. 10, or may be formed in a spiral shape as shown in FIGS. 11 and 12. Then, according to the embodiment shown in FIGS. 11 and 12, the pipe 7 can be easily fitted into the inner circumference of the grip ring 3.

Further, as shown in FIGS. 13 and 14, the grip ring 3 is provided with a groove-like portion 30 which is partially cut out along the substantially axial direction, or is cut into a thin wall along the substantially axial direction. The notched groove recesses 31 are provided in a groove shape, and the portions where the axial length of the grip ring 3 is shortened by the groove portions 30 and the thin portion of the grip ring 3 due to the groove recesses 31 are configured as the hinge portion 32. You can also Further, as shown in FIGS. 15 and 16, the hinge portion 32 may be provided with a groove recess 31 to make the hinge portion 32 thinner. With these configurations, elastic deformation at the time of expanding and contracting the diameter of the grip ring 3 becomes mainly the elastic deformation of expanding and contracting the interval dimension of the kerfs 14 around the hinge portion 32 by the hinge portion 32. The diameter of No. 3 and the diameter of No. 3 can be easily increased and workability can be improved. The groove-shaped portion 30 and the groove recess
31 may be formed in a direction slightly inclined with respect to the axial direction, or may be formed in a slightly corrugated shape like the kerf 14.

Further, on the outer peripheral surface of the grip ring 3, as shown in FIG.
3 and the embodiment shown in FIG. 14 and the embodiment shown in FIGS. 15 and 16, between the end portion of the joint main body 2 and the inner peripheral surface of the coupling nut 4 which protrudes annularly outward. You may provide the ring part 34 pinched | interposed by and which positions the grip ring 3.

As shown in the embodiment shown in FIG. 6, the embodiment shown in FIG. 7, the embodiment shown in FIGS. 13 and 14, and the embodiment shown in FIGS. When the end of 7 contacts the end of packing 25,
In particular, the grip ring 3 provided with the groove portion 30 and the groove recess 31.
When using, as shown in FIG.
The axial length of the grip ring 3 is set so that the end portion of the grip ring 3 on the side having a large outer diameter does not come into contact with the end surface of the ring portion, or as shown in FIGS. It is preferable to provide 34 to regulate the movement to the packing 25. That is, the grip ring 3
The end surface of the large diameter side is abutted, and the crimping force due to this abutment is larger than the crimping force with the packing 25 due to the abutment of the end surface of the pipe 7, and the crimping between the packing 25 and the end face of the pipe 7 is insufficient. If this happens, the fluid leaking from between the packing 25 and the tube 7 due to the pressure of the fluid flowing through the tube 7 may leak through the kerf 14, the groove portion 30, and the groove recess 31. For this reason, it is preferable that the grip ring 3 is not brought into contact with the end surface of the packing 25 so that the packing 25 and the end surface of the pipe 7 can be reliably pressure-bonded.

On the other hand, the joint main body 2 has been described by forming the connecting pipe portions 6 and 6 at both ends thereof in a substantially cylindrical shape coaxially, but it is L-shaped, and the connecting pipe portion 6 projects in three directions. One having a plurality of connecting pipe parts 6, 6 such as a T-shaped one provided, one having a different diameter of the insertion hole 5 of the connecting pipe part 6, screwed to one end of a male screw part of a flow port such as a tank Any pipe 7 through which a fluid such as a gas, a liquid, or a granular material flows, such as a pipe for branching the pipe 7 from a tank, which is provided with a female screw portion and a connecting pipe portion 6 on the other end side, Any structure for branching, connecting, etc. can be used.

[0045]

According to the grip ring for a pipe joint of the first aspect of the present invention, since the kerf is continuously provided over both end edges, the diameter can be expanded and reduced, and the allowable range of the fixed pipe diameter is increased. At the same time, when the diameter is expanded or reduced, the curvature of the inner peripheral surface is increased along the outer peripheral surface of the tube to be inserted in the entire axial direction. It can be crimped to the outer peripheral surface and the fixing strength of the pipe can be increased.

According to the grip ring for a pipe joint of claim 2, in addition to the grip ring for a pipe joint of claim 1, the kerf has convex portions and concave portions alternately in the circumferential direction, Since the convex portions that are alternately positioned overlap each other in the axial direction and are formed in a substantially wavy shape, it is possible to suppress the occurrence of twist in the kerf portion, and it is possible to further increase the allowable range of the fixed pipe diameter.

According to the grip ring for a pipe joint of the third aspect, in addition to the grip ring for a pipe joint of the first or second aspect, a groove recess is provided in a thin wall shape substantially along the axial direction. The thin portion acts like a hinge due to the recess,
Elastic deformation at the time of diameter expansion and diameter reduction can be easily performed, and workability can be improved.

According to the grip ring for a pipe joint of claim 4, in addition to the grip ring for a pipe joint according to any one of claims 1 to 3, a groove partially cut away along the substantially axial direction. Since the groove portion is provided, the portion of the groove portion whose axial length becomes shorter acts like a hinge, and elastic deformation at the time of diameter expansion and diameter reduction can be facilitated and workability can be improved.

According to the pipe joint of claim 5, the grip ring for a pipe joint according to any one of claims 1 to 4 is fitted and inserted into the insertion hole of the connecting pipe portion of the joint body. Insert the pipe into the grip ring exposed from the insertion hole of the connecting pipe part, screw the coupling nut that was previously inserted into the pipe into the connecting pipe part, and make the grip ring elastic at the inclined surface of the coupling nut. Since the claws on the inner peripheral surface are pressed against the outer peripheral surface of the tube to fix the tube, the clamping force acting in the tangential direction on the outer peripheral surface of the grip ring causes a small force to secure the tube. It can be firmly fixed with, and the range of pipe diameters that can be fixed with one grip ring can be increased, the number of parts can be reduced, parts can be easily managed, and workability can be improved.

According to the pipe joint of claim 6, claim 5
In addition to the described pipe joint, a step portion with a diameter smaller than the outer diameter of the pipe is formed to project inward on the inner peripheral surface of the joint body, and the end portion on the insertion side of the pipe abuts on this end portion. In order to install the ring-shaped packing in contact, by screwing the coupling nut to reduce the diameter of the grip ring, the tapered surface of the grip ring moves the pipe so that it is further inserted into the joint body, and the end of the pipe Since the part elastically deforms the packing and press-bonds it to the end surface, watertightness can be easily obtained.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of a pipe joint of the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is a side view showing the same grip ring.

FIG. 4 is a sectional view of the same.

FIG. 5 is a side view showing a state in which the diameter of the grip ring is reduced.

FIG. 6 is a partially cutaway side view showing another embodiment of the pipe joint of the present invention.

FIG. 7 is a partially cutaway side view showing still another embodiment of the pipe joint of the present invention.

FIG. 8 is a side view showing a grip ring of still another embodiment of the pipe joint of the present invention.

FIG. 9 is a side view showing a grip ring of still another embodiment of the pipe joint of the present invention.

FIG. 10 is a sectional view showing a grip ring of still another embodiment of the pipe joint of the present invention.

FIG. 11 is a plan view showing a grip ring of still another embodiment of the pipe joint of the present invention.

FIG. 12 is a sectional view of the same.

FIG. 13 is a plan view showing a grip ring of still another embodiment of the pipe joint of the present invention.

FIG. 14 is a sectional view of the same.

FIG. 15 is a plan view showing a grip ring of still another embodiment of the pipe joint of the present invention.

FIG. 16 is a sectional view of the same.

FIG. 17 is a partially cutaway side view showing still another embodiment of the pipe joint of the present invention.

FIG. 18 is a partially cutaway side view showing a conventional pipe joint.

[Explanation of symbols]

 1 Pipe joint 2 Joint body 3 Grip ring 4 Coupling nut 5 Insertion hole 6 Connecting pipe part 7 Pipe 11 Male screw part 13 Tapered surface 14 Cutting groove 15 Convex part 16 Recessed part 17 Claw part 20 Female screw part 21 Inclined surface 25 Packing 26 Step 30 Groove 31 Groove recess

Claims (6)

[Claims] 1. An elastically formed substantially cylindrical shape, a claw portion that abuts an outer peripheral surface of a pipe is provided on an inner peripheral surface of the substantially cylindrical shape, and an end on the outer peripheral surface where the pipe is inserted. A grip ring for a pipe joint, which has a tapered surface whose outer diameter decreases toward a portion, and is formed by continuously forming a kerf over both edges so that the diameter can be expanded and reduced. 2. The kerf is formed in a substantially wavy shape having alternating convex portions and concave portions in the circumferential direction, and the alternating convex portions are axially overlapped with each other. Grip ring for pipe fittings. 3. The grip ring for a pipe joint according to claim 1, wherein a groove recess having a thin wall is provided along the substantially axial direction. 4. The grip ring for a pipe joint according to claim 1, wherein a groove-shaped portion, which is partially cut away, is provided along the substantially axial direction. 5. A grip ring for a pipe joint according to any one of claims 1 to 4, and a male screw portion is provided on an outer peripheral surface into which an insertion hole for inserting a pipe is opened and a side having a large outer diameter of the grip ring is inserted. A joint body having a substantially cylindrical connecting pipe portion, an internal thread portion on one end side that is screwed into the male screw of the connecting pipe portion, and an inner peripheral surface on the other end side on the other end side. The cup having a substantially cylindrical shape having an inclined surface for reducing the diameter of the grip ring by tightening the side of the grip ring having a smaller outer diameter by screwing the female thread portion to the male screw portion A pipe joint comprising a ring nut. 6. The joint main body is provided with an inner peripheral surface projecting inward and a step portion having an inner diameter smaller than the outer diameter of the pipe, and one end surface in the axial direction is brought into contact with the step portion and mounted. The pipe joint according to claim 5, further comprising: an annular packing with which an end portion on the insertion side of the pipe abuts on the other end surface in the axial direction.