JPH0716151Y2 - Pipe joint structure - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint structure, and more particularly to a pipe joint structure suitable for a water supply pipe in a structure.

[0002]

2. Description of the Related Art Generally, stainless steel pipes are used as water supply pipes in a building or the like. As a joint structure for this kind of piping, one pipe end portion A is fitted into a socket portion 1'formed on the other pipe end portion B as shown in Figs. 7 and 8, and is inserted into the socket portion. A type in which packing is fitted is known.

In this joint, the pipe end portion A is composed of an insertion pipe portion 2 to be inserted into the socket portion 1'and an annular bulge portion 3 formed on the outer periphery of the end of the insertion pipe portion. ,
Inside the socket portion 1 ′ on the pipe end B side, a pipe fitting portion 4 into which the tip of the insertion pipe portion 2 is fitted and a tapered packing fitting portion 5 ′ are formed. An annular packing 6'made of an elastic material such as synthetic rubber is fitted between the tube portion 2 and the packing fitting portion 5 '. Then, the pressing ring 7 ′ externally inserted from the pipe end portion A side is fastened and fixed to the flange portion 9 of the socket portion 1 ′ by the fastening bolt 8, and the pressing ring 7 ′ has an inner peripheral edge portion at the pipe end portion. By engaging the annular bulging portion 3 of A, the pipe end portion A is pressed inward of the socket portion 1 ′ via the annular bulging portion 3, whereby the annular packing 6 ′ is moved to the packing fitting portion 5. The space is compressed between the tapered inner peripheral surface of ′ and one inclined surface of the annular bulging portion 3, and a seal is formed at this portion.

The annular packing 6'of this pipe joint is also used.
9 has a structure in which an annular groove 61 'is formed on the end surface facing the inside of the socket portion as shown in FIG. 9, and when water pressure is applied to the packing, the annular groove 61' serves as a pressure receiving portion and the annular packing The 6'is pressed against the packing fitting section 5'and the insertion tube section 2 to obtain high sealing performance. In this type of joint, the water is constantly
Flow in the direction.

[0005]

However, such a conventional joint structure has a problem that water leaks from the packing portion when a high water pressure is applied. That is, when the water pressure in the pipe is high, a very large pressure is exerted on the annular packing 6'of the joint so as to push it toward the outside of the socket portion, and such water pressure may be applied repeatedly or for a certain period of time. The annular packing 6 ′ is elastically deformed (expanded and deformed) to form a tapered packing fitting portion 5.
′, It escapes to the outside of the socket portion, and finally overlies the annular bulging portion 3 as shown by the chain line in FIG. 8, and as a result, the sealing property of this portion is significantly impaired and water leakage occurs.
In particular, in a water supply pipe installed in a building or the like, the water may suddenly flow backward with respect to the steady water flow direction shown in FIG.
A very large water pressure acts to push this toward the outside of the socket portion, and the above-mentioned water leakage is likely to occur.

The present invention has been made in view of such conventional problems, and it is an object of the present invention to provide a pipe joint structure capable of obtaining a reliable sealing effect for a long period of time when applied to a water supply pipe or the like. .

[0007]

In order to achieve such an object, the present invention has the following configuration. (1) A pipe joint structure configured by fitting one pipe end portion into a socket portion formed in the other pipe end portion, wherein one pipe end portion is an insertion pipe portion and this insertion pipe portion. A ring-shaped bulging portion formed on the outer periphery of the terminal end, and a pipe fitting portion and a packing fitting portion, into which the tip of the insertion pipe portion is fitted, inside the socket portion in order from the inner side thereof. Is formed, an annular packing made of an elastic material is fitted between the insertion pipe portion and the packing fitting portion, and a holding ring externally inserted at one pipe end portion is fastened and fixed to the socket portion, The pressing ring has a pipe joint structure in which an inner peripheral edge portion thereof engages with the annular bulging portion and one end of the pipe is pressed inwardly of the socket portion through the annular bulging portion. The peripheral surface of the packing fitting part where the surfaces are pressed against each other is parallel to the pipe axis direction or The inner diameter of the annular packing is the same as that of the annular packing formed on the end surface of the annular packing that faces the inner side of the socket section. A joint structure for a pipe, in which a metal ring smaller than the outer diameter of the top of the annular bulge is embedded.

(2) A pipe joint structure according to the above-mentioned structure (1), in which an annular projection for pressing the annular packing is formed on the side of the pressing ring facing the socket.

(3) The pipe joint structure according to the above (1), in which a ring body for pressing the annular packing is interposed between the holding ring and the annular packing.

(4) The above (1), (2) or (3)
In the above structure, the pipe joint structure in which the presser ring is fastened and fixed to the socket portion by fastening bolts.

(5) The above (1), (2) or (3)
In the above structure, the presser ring has a male screw portion, and the pipe joint structure is fastened and fixed to the socket portion through a female screw portion formed in the socket portion.

The pipe joint structure of the present invention is not limited to water pipes and water supply pipes, but can be applied to joints for all pipes for fluids.

[0013]

In the pipe joint of the present invention, the metal ring inside the annular packing engages with the annular bulging portion through the packing component even if a large water pressure is applied to the annular packing toward the outside of the socket. Moreover, since the peripheral surface of the packing fitting portion, to which the outer peripheral surface of the annular packing should be pressed, is configured to expand in parallel to the pipe axis direction or toward the inside of the socket, the annular packing expands. There is no room for diametrical deformation to escape to the outside of the socket, and therefore, the annular packing does not displace to the outside of the socket and ride over the annular bulge. As a result of suppressing the displacement of the annular packing to the outside of the socket portion in this way, the packing pressure on both sides of the annular groove causes the packing portions on both sides of the annular groove to move in the pipe radial direction (the direction of the packing fitting portion and the insertion pipe portion). Direction), and even at the portion of the metal ring that is engaged with the annular bulging portion via the packing component, the annular packing has the circumferential surface of the packing fitting portion and the insertion pipe portion peripheral surface or the annular bulging portion. Since it is strongly pressed against the inclined surface of, the high sealing property can be obtained in these portions.

[0014]

1 to 3 show an embodiment of the present invention, in which A and B are pipe end portions to be joined, and a socket portion 1 in which the pipe end portion A is formed in the pipe end portion B is shown. The joint is configured by being inserted into.

The pipe end portion A is composed of an insertion pipe portion 2 which is inserted into the socket portion 1 on the side of the pipe end portion B, and an annular bulge portion 3 which is formed on the outer periphery of the end of the insertion pipe portion. ing. The annular bulging portion 3 is composed of a bulging portion having a mountain-shaped cross section called a bulge. Socket part 1 on the pipe end B side
A pipe fitting portion 4 into which the tip of the insertion pipe portion 2 is fitted and a packing fitting portion 5 are formed inward from the inside in order. The outer peripheral surface 51 of the packing fitting portion 5 to which the outer peripheral surface of the annular packing is to be pressed is parallel to the pipe axis direction.
That is, it is configured to be perpendicular to the pipe radial direction.

An annular packing 6 made of an elastic material such as synthetic rubber or soft plastic is fitted between the insertion tube portion 2 and the packing fitting portion 5. FIG. 3 is a perspective view showing the annular packing 6 in a cross-sectional state. In the annular packing 6, an annular groove 61 is formed on the end face facing the inner side of the socket part, and the annular packing 6 is formed inside the outer part of the socket part. As shown in FIG. 2, a metal ring 10 having an inner diameter d smaller than the outer diameter D of the top of the annular bulging portion 3 is embedded. The metal ring 10 is preferably made of a material that has a certain degree of strength and is less elastically deformed in the radial direction. For example, a metal plate such as a stainless plate punched into a ring shape is used.

A holding ring 7 is externally attached to the pipe end A side,
The pressing ring 7 is fixed to the socket portion 1 by fastening the circumferential portion thereof to the flange portion 9 of the socket portion 1 with fastening bolts 8. In this embodiment, an annular protrusion 71 for pressing the annular packing 6 is formed on the side of the holding ring 7 facing the socket portion. The holding ring 7 presses the tube end portion A inwardly of the socket portion 1 through the annular bulge portion 3 by engaging the inner peripheral edge portion with the annular bulge portion 3 of the pipe end portion A. The annular protrusion 71 presses the annular packing 6 inward of the socket 1. Thereby, the annular packing 6 is compressed between the peripheral surface 51 of the packing fitting portion 5 and one inclined surface of the insertion tube portion 2 or the annular bulging portion 3, and a seal is formed in this portion.

FIG. 4 shows another embodiment of the present invention.
Instead of providing the annular projection 71 on the pressing ring 7, a ring body 11 for pressing the annular packing is interposed between the pressing ring 7 and the annular packing 6. The material of the ring body 11 may be either metal or resin material such as synthetic rubber. For other configurations, see FIG.
Since it is the same as the embodiment shown in FIG. 3, the same reference numerals are given and the description thereof is omitted.

FIG. 5 shows another embodiment of the present invention.
The peripheral surface 51 of the packing fitting portion 5 to which the outer peripheral surface of the annular packing is to be pressed is tapered (α: taper angle), that is, the diameter is expanded toward the inside of the socket portion. Since the other structures are the same as those of the embodiment shown in FIGS. 1 to 3, the same reference numerals are given and the description thereof will be omitted.

FIG. 6 shows an embodiment in which the pressing ring 7 is of a screw type and has a structure suitable for a pipe joint having a relatively small diameter. In this embodiment, a male screw portion is provided on the outer circumference of the holding ring 7 and a female screw portion is provided on the inner circumference of the socket portion 1. The holding ring 7 is fastened to the socket portion 1 via the female screw portion. Fixed. Since the other structures are the same as those in the above-mentioned embodiment, the same reference numerals are given and detailed description will be omitted. Further, in the structure of FIG. 6, a ring body 11 as shown in FIG. 4 may be interposed instead of providing the annular protrusion 71.

Next, the operation of the joint structure of the present invention will be described based on the above embodiment. In the pipe joint of the present invention, water constantly flows in the direction of arrow X in FIG. When a large water pressure is applied to the annular packing 6 such that the annular packing 6 is pushed outward, the metal ring 10 inside the annular packing 6 engages with the annular bulging portion 3 via the packing component, and
Since the outer peripheral surface 51 of the packing fitting portion 5 against which the outer peripheral surface of the annular packing 6 is pressed is configured to expand in parallel to the tube axis direction or toward the inside of the socket portion, the annular packing 6 expands. There is no room for diameter deformation and escape to the outside of the socket. Therefore, it is possible to reliably prevent the annular packing 6 from displacing to the outside of the socket and getting over the annular bulging portion 3. And thus the annular packing 6
As a result of suppressing the outward displacement of the socket, the annular groove 6
Due to the water pressure applied inside 1, the packing portions 62 and 63 on both sides of the annular groove 61 are strongly pressed in the direction of the packing fitting portion 5 and the direction of the insertion tube portion 2, respectively, and further the annular bulge is caused via the packing component member. Even at the portion of the metal ring 10 that is engaged with the portion 3, the annular packing 6 is strongly pressed against the peripheral surface 51 of the packing fitting portion 5 and the peripheral surface of the insertion tube portion 2 or the inclined surface of the annular bulging portion 3, so A high sealing property can be obtained in the part.

[0022]

According to the joint structure of the present invention described above,
Even if a large amount of water pressure is applied to the packing part repeatedly or for a long period of time, the packing is properly prevented from displacing to the outside of the socket part, and a high sealing effect is obtained in the packing part, so that water leakage can be prevented for a long time. Can be reliably prevented.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a pipe joint structure of the present invention.

FIG. 2 is a partially enlarged view of the annular packing of FIG. 1 and its peripheral portion.

3 is a perspective view showing a cross section of the annular packing shown in FIG.

FIG. 4 is a longitudinal sectional view showing another embodiment of the pipe joint structure of the present invention.

FIG. 5 is a vertical sectional view showing another embodiment of the pipe joint structure of the present invention.

FIG. 6 is a vertical sectional view showing another embodiment of the pipe joint structure of the present invention.

FIG. 7 is a vertical sectional view of a conventional pipe joint structure.

8 is a partially enlarged view of the annular packing of FIG. 7 and its peripheral portion.

9 is a perspective view showing the annular packing shown in FIG. 7 in a sectional view.

[Explanation of symbols]

1 ... Socket part, 2 ... Insertion pipe part, 3 ... Annular bulge part, 4 ...
Tube fitting part, 5 ... Packing fitting part, 6 ... Annular packing, 7 ... Holding ring, 8 ... Fastening bolt, 10 ... Metal ring, 11 ... Ring body, 51 ... Circumferential surface, 61 ... Annular groove, A,
B ... Pipe end

Claims (5)

[Scope of utility model registration request] 1. A pipe joint structure constituted by fitting one pipe end portion into a socket portion formed in the other pipe end portion, wherein one pipe end portion is an insertion pipe portion and this insertion portion. An annular bulge portion formed on the outer periphery of the end of the pipe portion, and inside the socket portion, in order from the inner side thereof, a pipe fitting portion into which the tip of the insertion pipe portion is fitted and a packing fitting portion. A ring-shaped packing made of an elastic material is fitted between the insertion pipe portion and the packing fitting portion, and a holding ring externally attached to one pipe end is fastened to the socket portion. In the pipe joint structure, wherein the pressing ring is fixed, an inner peripheral edge portion of the pressing ring engages with the annular bulging portion, and one pipe end portion is pressed inwardly of the socket portion through the annular bulging portion. The outer peripheral surface of the packing is in pressure contact. Is configured to expand toward the inside of the socket, and an annular groove is formed on the end surface of the annular packing facing the inside of the socket. A pipe joint structure, wherein a metal ring smaller than the outer diameter of the top of the annular bulge is embedded. 2. The side of the presser ring facing the socket portion,
The pipe joint structure according to claim 1, wherein an annular projection portion that presses the annular packing is formed. 3. Between the presser ring and the annular packing,
The pipe joint structure according to claim 1, wherein a ring body for pressing the annular packing is interposed. 4. The pipe joint structure according to claim 1, 2 or 3, wherein the presser ring is fastened and fixed to the socket portion with fastening bolts. 5. The pipe joint structure according to claim 1, wherein the presser ring has a male screw portion, and is fastened and fixed to the socket portion via a female screw portion formed in the socket portion.