JPS5811984Y2 - pipe fittings - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pipe joint for use with synthetic resin or resin-coated pipes.

In recent years, synthetic resin pipes or resin-coated pipes are increasingly being used instead of metal pipes as pipes for transporting gas, water, and the like.

However, when connecting these resin-made or resin-coated pipes, it is not possible to provide a threaded portion on the pipe and screw it into a pipe joint, as with connecting metal pipes.

For this reason, a conventional pipe joint for resin or resin-coated pipes as shown in FIG. 1 has been developed.

In Fig. 1, 1 is the joint body, and 2 is the joint body 1.
A ring-shaped packing 3 is fitted into the packing accommodating portion.

4 is a retainer; 5 is a partially cut-out ring-shaped retaining ring having a tapered surface 6 on the outer circumferential surface and teeth 7 on the inner circumferential surface; 8 is a retainer ring screwed onto the inner circumferential surface of the opening of the joint body 1; A mating cylindrical press ring has a tapered surface 9 on its inner circumferential surface, and presses against the tapered surface 6 of the retaining ring 5.

In this pipe joint, the pipe 10 is inserted into the joint body 1, and the push ring 8
When rotated and tightened to the main body 1, the press ring 8 presses the packing 3 through the retainer 4, and the packing 3 is pressed against the inner surface of the main body 1 and the outer circumferential surface of the pipe 10, and the joint main body 1 and the pipe 10 are Airtightness between and is ensured.

Similarly, the tapered surface 9 of the press ring 8 presses the tapered surface 6 of the retaining ring 5, reducing the diameter of the retaining ring 5, and the biting teeth 7 engage the pipe 10, and the pipe 10 is pushed into the fitting body 1.
It is to be fixed at

However, in such a pipe joint, the pipe 1
The outer diameter of 0 may vary depending on manufacturing tolerances, and in the case of resin pipes or resin-coated steel pipes, the surface of the pipe is more flexible than metal, so the retaining ring 5 is first wedged into the pipe 10, and this retaining ring 5 prevents the push ring 8 from moving forward by a predetermined length,
This has the disadvantage that a predetermined surface pressure cannot be applied to the packing 3, and sufficient airtightness may not be ensured.

The present invention was developed based on these circumstances, and its purpose is to eliminate the above-mentioned drawbacks that have occurred in conventional pipe fittings, and to ensure sufficient airtightness between the pipe and the pipe fitting. To provide a pipe joint which can securely prevent the pipe from being pulled out even if a force in the pulling direction is applied to the pipe.

In order to achieve the above object, the present invention includes a joint body having a gasket accommodating portion at the open end, a ring-shaped gasket accommodated in the gasket accommodating portion of the joint body, and a ring-shaped gasket that abuts the outer peripheral end surface of the gasket. a retainer, a ring-shaped retaining ring that abuts the outer end surface of the retainer, has a tapered surface on its outer circumferential surface, and has a partially cut-out retaining ring having teeth embedded in its inner circumferential surface; A pipe joint comprising a press ring having a stepped tapered surface that is screwed onto the inner circumferential surface or the outer circumferential surface of the retaining ring and is pressed against the tapered surface of the retaining ring to reduce the diameter of the ring, By providing a stepped tapered surface on the inner periphery and pressing the tapered surface of the retaining ring with this stepped tapered surface, the action of reducing the diameter of the retaining ring and the action of compressing the seal are performed separately. It is possible to ensure airtightness between the pipe and pipe fitting,
The pipe is designed to be reliably prevented from being pulled out.

Embodiments of the present invention are shown in FIGS. 2 and 3 and explained in detail below.

FIG. 2 shows a state in which the resin pipe 21 is fitted into the pipe joint 20.

In the figure, reference numeral 22 denotes a pipe joint body, and a gasket accommodating portion 23 is provided at the opening thereof, and a ring-shaped gasket 24 is fitted into this gasket accommodating portion 23.

A ring-shaped retainer 2 is attached to the outer end surface of the packing 24.
One end surface of the retainer 25 is in contact with the other end surface of the retainer 25.
A retaining ring 28 that is ring-shaped and has a tapered surface 26 on its outer circumferential surface and has teeth 27 embedded in its inner circumferential surface and is partially cut out.
are in contact and inserted.

A cylindrical push ring 29 is provided at the open end of the pipe joint body 22 and is screwed onto the inner peripheral surface of the open end. However, a stepped tapered surface 33 consisting of a first tapered surface 31 and a second tapered surface 32 is provided in pressure contact with the tapered surface 26 of the retaining ring 28.

Note that 35 is a stiffener that is fitted into the opening of the resin pipe 21.

According to such a configuration, when the push ring 29 is rotated and tightened into the opening of the joint body 22, the stepped tapered surface 33
The first tapered surface 31 presses the tapered surface 26 of the retaining ring 28, the retaining ring 28 is reduced in diameter, and its biting teeth 27 sink into the outer peripheral surface of the resin tube 21.

Subsequently, when the push ring 29 is tightened, the straight surface 30 of the push ring 29 slides on the outer circumferential surface of the retaining ring 28, and the open end of the push ring 29 presses the retainer 25, causing the retainer 25 to tighten.
The packing 24 is pressed through the pipe to create an airtight space between the pipe joint body 22 and the resin pipe 21.

When the press ring 29 is further tightened, the state shown in FIG. 3 is obtained, and the second tapered surface 32 of the press ring 29 presses against the tapered surface 26 of the retaining tongue 28, and the retaining ring 28 is further reduced in diameter to form the bite tooth. 27 sinks into the outer circumferential surface of the resin pipe 21 and securely fixes the resin pipe 21 to the pipe joint body 22.

Therefore, the press ring 2 screwed into the opening of the pipe joint body 22
The tapered surface provided on the inner circumferential portion of 9 is a stepped tapered surface 33 consisting of first and second tapered surfaces 31 and 32 and a straight surface 30 forming a step in the middle, and a retaining ring is formed. 28 was reduced in diameter by the first. Second tapered surface 31.3
2 is pressed against the tapered surface 26 of the retaining ring 28, and during this process, the straight portion 30 slides on the outer circumferential surface of the retaining ring 28, and the press ring 29 presses against the tapered surface 26 of the retaining ring 28. Since this is done at the stage of screwing forward without reducing the diameter of the push ring 28, the retaining ring 28 digs deeply into the outer peripheral surface of the pipe 21 like in a conventional pipe joint, preventing the pushing ring 29 from moving forward by a predetermined length. The drawback that a predetermined surface pressure cannot be applied to the packing 24 and sufficient airtightness cannot be ensured is eliminated.

In addition, the retaining ring 28 is attached to the first. Second tapered surface 31.
32, the retaining ring 28 is first fixed to the pipe 21 by the first tapered surface 31 to a predetermined depth, and in the next step, the retaining ring 28 is pressed to a predetermined depth by the seal 24. After applying surface pressure and ensuring sufficient airtightness, the second tapered surface 32 allows the retaining ring 28 to be further deeply inserted into the tube 21, so that the tube 21 is fixed even more firmly, and the tube 21 When a force in the pulling direction is applied to the retaining ring 28, the second tapered surface 32 presses the tapered surface 26 of the retaining ring 28, and prevents the pipe 21 from being pulled out from the pipe joint body 22.

Note that since the first tapered surface 31 allows the retaining ring 28 to be inserted into the pipe 21 by a predetermined depth, it may have a curved shape that expands outward, for example.

Further, FIG. 4 shows an embodiment in which the push ring 29' is screwed onto the outer peripheral surface of the opening of the joint body.

Incidentally, members common to those in the above embodiment are given the same numbers and explanations thereof will be omitted.

As described above, the present invention provides a stepped tapered surface that separates the straight surface and the tapered surface from the straight surface and the tapered surface on the inner circumference of the push ring that is screwed into the opening of the pipe joint body, and the straight surface allows the taper of the retaining ring to be adjusted. In the middle of pressing the surface, the press ring can advance a predetermined distance to firmly press the seal, ensuring airtightness between the pipe and the pipe fitting, and
The pipe is fixed to the fitting body by pressing the tapered surface against the tapered surface of the retaining ring that is wedged into the outer circumferential surface of the pipe. Even if the pipe is more flexible than a metal pipe, it is possible to provide a pipe joint that does not cause problems such as the retaining ring getting wedged into the pipe and making it impossible to ensure sufficient airtightness.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a conventional pipe joint.
The figure is a sectional view showing an embodiment of the present invention, Fig. 3 is a sectional view showing the pushing ring of the same embodiment in a tightened state, and Fig. 4 is a sectional view showing the pushing ring of the same embodiment in a tightened state. FIG. 1 is a sectional view of a main part of an embodiment. 22... Joint body, 23... Packing housing part, 24... Packing, 25...
Retainer, 26...Tapered surface, 27...
- Biting teeth, 28... Removal prevention ring, 29.
...Press ring, 33...Stepped tapered surface.

Claims (1)

[Scope of utility model registration request] A joint main body having a gasket accommodating portion at an open end, a ring-shaped gasket accommodated in the gasket accommodating portion of the joint body, a ring-shaped retainer abutting the outer end surface of the gasket, and a ring-shaped retainer abutting the outer end surface of the retainer. a ring-shaped contacting ring-shaped ring having a tapered surface on its outer circumferential surface and a partially cut-out retaining ring having a recessed tooth on its inner circumferential surface; and a press ring having a stepped tapered surface that presses against the tapered surface of the retaining ring to reduce the diameter of the ring.