JPH0257789A - Pipe joint - Google Patents

Abstract

PURPOSE:To aim at checking a pipe joint from coming off, by providing a joint body having a conical tapered body and an annular checking member formed with a slit in a peripheral part thereof so as to be split, in a cylindrical inner peripheral section into which a pipe to be connected is inserted. CONSTITUTION:A pipe joint is composed of a cylindrical joint body 10 adapted to be fitted on one end part of, for example, a vinyl chloride pipe 4 to be connected, a sealing member 20 disposed in the joint body 10, and a checking member 30. The joint body 10 is formed, in the vicinity of an opening 11, with a recess groove 12 adapted to be fitted therein with an annular sealing member 20. A recess groove 13 for receiving the checking member 30 is formed in the inward inner surface part of the joint body 10, which is, for example, an annular metal wire having a slit 31, and having in its inner peripheral part a saw tooth- like locking part 32. The cut-in depth of the locking part 32 is small in the vicinity of the slit, and is increased gradually as the distance from the slit increases. As a result, the connection can be surely made without the pipe to be connected being damaged.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a pipe joint used for piping such as water pipes and gas pipes.

(Conventional technology) As a pipe fitting used for plumbing such as water pipes.

Recently, plug-in type pipe joints have been developed that can secure connecting pipes by simply inserting the pipes to be connected. In such a plug-in type pipe joint, it is necessary that the end of the connecting pipe can be easily inserted, and that the inserted end of the connecting pipe cannot be easily pulled out. For this reason, in plug-in type pipe fittings, as disclosed in Japanese Utility Model Application Publication No. 55-80586, it is usually necessary to fix the connecting pipe within the cylindrical joint body having a tapered inner surface. A split ring is provided. The split ring is divided into parts with slits formed in a part of the nine circumferential directions, and the diameter can be contracted or expanded. The split ring has a slightly smaller diameter than the connecting pipe when it is not fitted onto the end of the connecting pipe, and when the connecting pipe is inserted into the fitting body, the split ring expands in diameter. A connecting tube is then inserted into the split ring.

The split ring is fitted onto the outer circumferential surface of the connecting pipe, and when the connecting pipe is about to come out of the joint body, the 10-split ring comes into contact with the tapered surface on the inner peripheral surface of the joint body and its diameter is reduced, causing the connecting pipe to It is locked. As a result, the connecting pipe is restrained by the split ring and prevented from coming off from the joint body.

(Problems to be Solved by the Invention) In such conventional pipe joints, a substantially uniform force is applied from the split ring over the entire circumference in the radial direction to the connecting pipe inserted into the split ring. There is. If a force is applied to the connecting pipe in the direction of pulling it out of the joint body, and the split ring contacts the tapered surface of the inner circumferential surface of the joint body and contracts in diameter, then 1. For example, if the connecting pipe is a vinyl chloride pipe, 1 As the diameter of the split ring is reduced, the locking portion of the split ring bites into the entire circumference of the vinyl chloride pipe. Furthermore, when the force acting on the connecting pipe in the direction of pulling it out of the joint body increases, the vinyl chloride pipe is deformed to reduce its diameter, and the locking part on the inner surface of the split ring bites into the outer circumferential surface of the vinyl chloride.

The split ring is firmly fitted onto the outer peripheral surface of the vinyl chloride pipe.

When the split ring comes into contact with the tapered surface of the joint body and reduces its diameter, it is in a state where parts of the two circumferential directions are divided, so it is split in the two circumferential directions so that the parts near the slits approach each other. A tensile force acts. At this time, the diameter of the area near the slit is relatively easily reduced by the tensile force, but as the distance from the slit increases, the action of the tensile force weakens and the diameter reduction rate decreases. The diameter reduction rate of the split ring is minimized at the portion facing the slit. Therefore, the 2-split ring has different diameter reduction rates in the circumferential direction.

There are usually 9 serrated locking parts on the inner surface of the split ring.
The depth of cut is constant over the entire circumference, and the shape is constant over the entire circumference. The split ring is
As mentioned above, since the diameter reduction ratio differs in the circumferential direction, the locking portion of the split ring near the slit will firmly lock onto the connecting pipe due to the diameter reduction deformation of the connecting pipe, but the Since the deformation of the connecting pipe is small in the part where the connecting pipe is connected, the locking force is small. As a result, a force that tries to pull the connecting pipe out of the split ring acts on the part of the connecting pipe that faces the slit, and there is a risk that the locking part of the split ring at the part facing the slit and the outer circumferential surface of the connecting pipe will become unlatched. be. In this state, a force is applied to the split ring so that it is tilted with respect to the connecting pipe, and a force is applied to the connecting pipe in a direction that widens the slit of the split ring, that is, a direction that increases the diameter of the split ring. and.

If the force increases, the connecting tube will come out of the split ring.

In addition, if the depth of cut of the locking part is increased, the connecting pipe will not come out from the split ring, but if the depth of cut is increased, the diameter of the split ring will be reduced and the connection pipe will be bitten in the vicinity of the slit. The amount will increase and the connecting pipe will be damaged.

The present invention solves the above-mentioned conventional problems, and its purpose is to provide a pipe joint that is highly effective in preventing the connecting pipe from coming off the joint body.

Still another object of the present invention is to provide a pipe joint that can reliably restrain a connecting pipe without damaging the connecting pipe even when high pressure is applied to the connecting pipe in a direction in which the connecting pipe is pulled out from the joint body. .

(Means for Solving the Problems) The pipe joint of the present invention has a cylindrical shape in which the end of the connecting pipe is inserted through an opening at one end, and the inner circumferential side of the pipe joint has a cylindrical shape that is inserted into the opening at one end. The joint body has a conical tapered part whose diameter gradually decreases as the diameter increases, and the joint body has a circumferentially tapered part disposed within the joint body so as to be able to fit onto a connecting pipe inserted into the joint body. A retaining member has a ring shape divided into parts with a slit formed therein, and has a sawtooth-like locking portion around the entire inner circumference of the retaining member, and the cutting amount of the locking portion is adjustable. .

It is characterized in that the area near the slit is small and becomes larger as it moves away from the slit, thereby achieving the above object.

(Example) The present invention will be described below with reference to Examples.

As shown in FIG. 1, the pipe joint of the present invention includes a cylindrical joint body 1O that is fitted onto the end of a connecting pipe 40 made of, for example, vinyl chloride, and a seal disposed inside the joint body IO. material 20 and the retaining member 3 similarly disposed within the joint body 10.
0.

The joint body 10 in the pipe joint of the present invention has an opening 11 at one end into which the connecting pipe 40 is inserted, and the opening 11
An annular sealing material concave groove 12 is provided on the inner circumferential surface of the vicinity. The sealing material concave groove 12 is.

The opening 11 side part is deep and the inner back side part is shallow, and a sealing material 20 made of, for example, rubber is fitted and fixed in the groove 12 for sealing material.

The sealing material 20 is in close contact with the outer circumferential surface of the end of the connecting tube 40 inserted into the joint body 1O, and liquid-tightly seals the outer circumferential surface of the connecting tube 40 and the inner circumferential surface of the joint body 10.

A retaining member groove 13 is provided on the inner circumferential surface of the joint body 10 on the axially innermost side of the joint body 10 than the sealing material groove 12 . Recessed groove 13 for the retaining member
An annular retaining member 30 is fitted inside.

The retaining member 30 is, as shown in FIG.
1 is formed. The retaining member 30 has a slightly smaller diameter than the outer diameter of the connecting pipe 40 inserted into the joint body 10, and when the connecting pipe 40 is inserted into the retaining member 30, the retaining member 30 expands in diameter so that the slit 31 widens. When the connecting tube 40 is inserted into the retaining member 30, the connecting tube 40 is locked to the outer circumferential surface of the connecting tube 40 due to the diameter reduction acting on the retaining member 30.

A sawtooth-shaped locking portion 32 is formed on the inner peripheral side of the retaining member 30 . The locking portion 32 has 9, for example, a third
As shown in the figure and FIG. 4, an annular retaining ring 3
A first flat surface 32a along the radial direction of 0.

A first inner circumferential surface 32b orthogonal to the first flat surface 32a, which is connected to the inner back side of the joint body IO of the first flat surface 32a, a second flat surface 32c orthogonal to the first inner circumferential surface 32b, The second inner peripheral surface 32d of the second flat surface 32c connected to the inner side of the joint body 10 and the peripheral surface of the retaining ring 30 form a sawtooth shape. The amount of cut in the serrated locking portion 32 of the retaining ring 30 is as follows.

It is small in the vicinity of the slit 31 (but gradually becomes larger as it moves away from the slit 31;
It is largest in the opposing part. That is, the cutting depth Hl of the first flat surface 32a at the opposing portion of the sulin 31 shown in FIG. 4 is larger than the cutting depth Hz of the first flat surface 32a in FIG. Such a retaining member 30 can be easily manufactured by, for example, forming a metal wire into an annular shape and then cutting the metal wire with the center position slightly shifted toward the side facing the slit.

Recessed groove 13 for retaining member into which retaining member 30 is fitted
has a space slightly larger than the retaining member 30 in the innermost part of the joint body 10. Concave groove 13 for retaining member
The inner back side surface 13b of the joint body 10 is approximately orthogonal to the axis of the joint body 10. The retaining ring concave groove 13 is located on the opening 11 side of the joint body 10.
It has a conical taper portion 13a whose diameter gradually decreases toward the opening 11 side.

In the pipe joint having such a configuration, an annular retaining member 30 is fitted into the retaining member groove 13 of the joint body 10, and a sealing material 20 is fitted into the sealing material concave groove 12. It has been fixed. and.

When the connecting tube 40 is inserted from the opening 11 of the joint body IO, the tip of the connecting tube 40 presses the retaining member 30 and pushes the retaining member 30 against the inner side surface 13b of the groove 13.
hit it against. When the connecting pipe 40 is further pushed into the joint body 10 in this state, the retaining member concave groove 13
The connecting pipe 40 is inserted by expanding the diameter of the retaining member 30 that is in contact with the inner inner side surface 13b.

When water, for example, is passed through the joint body 10 and the connecting pipe 40 in such a joined state, a force is applied to the connecting pipe 40 in the direction of pulling it out from the joint body 10, and the connecting pipe 40 , moves in the direction of coming out of the joint body IO. With this movement, the retaining member 30 fitted onto the connecting pipe 40 in the joint main body IO moves in parallel with the connecting pipe 40. Then, the outer peripheral surface of the retaining member 30 comes into contact with the conical tapered portion 13a of the retaining member concave groove 13, as shown in FIG.

In this state, when the connecting pipe 40 further moves in the direction of coming out from the joint body 10, the retaining member 30 has a gap from the conical taper portion 13a of the retaining member concave groove 13, as shown in FIG. A reaction force is applied, and a force along the tapered portion 13a is applied. Due to this.

9. While a torsional force is applied to the retaining member 30 in the direction indicated by arrow A in FIG. The locking portion 32 with the smallest diameter bites into the outer peripheral surface of the connecting pipe 40. Furthermore, when a large pullout force is applied, the liquid stopper member 30 is twisted.

As shown in FIG. 6, the locking portion 32 of the liquid leak prevention member 30 bites into the outer peripheral surface of the connecting pipe 40 and is locked.

At this time, the serrated locking portion 32 of the retaining member 30 is
The amount of cut near the slit 31 is small, and the slit 31
It gradually gets bigger as you move away from it. As a result, as the locking portion 32 moves away from the slit 31,
The amount of biting into the outer peripheral surface of the connecting pipe 40 increases, and the slit 3
In the part facing 1, the amount of biting is maximum. On the other hand, the retaining member 30 has a large diameter reduction in the vicinity of the slit 31, so even though the amount of biting of the locking part 32 in the vicinity of the slit is relatively small,
The locking force on the outer peripheral surface of the connecting tube 40 increases, and eventually the retaining member 30 restrains the outer peripheral surface of the connecting tube 40 with a substantially uniform locking force over the entire circumference in the circumferential direction.

The amount of cut of the serrated locking portion 32 in the retaining member 30 varies depending on the material and shape of the connecting pipe 40, the diameter of the metal wire constituting the retaining member 30, etc.8 For example, if the connecting pipe 40 has an outer diameter 216 rlIm, a PVC pipe with a wall thickness of 11 mm, and when the outer diameter of the metal wire constituting the retaining member 30 is 9 mm, the first The cutting depth H3 of the flat surface 32 is about 0.7M, and the cutting depth H3 of the first flat surface of the part facing the slit! is approximately 1.0 to 1.1 an.

In addition, in the above embodiment, it is used as a retaining member.

Although the description has been made regarding a metal wire formed into an annular shape, the present invention is not limited to this type of material.2 For example, the retaining member may have a cylindrical shape and have a plurality of saw teeth on its inner peripheral surface. A locking portion having a shape is formed, and the depth of cut of the locking portion is small in the vicinity of the slit and becomes thicker as the distance from the slit increases.

(Effects of the Invention) As described above, in the pipe joint of the present invention, the depth of cut in the serrated locking portion formed on the inner peripheral side of the retaining member having a slit is smaller in the vicinity of the slit, and is smaller than the slit. Since the diameter increases as the distance increases, the amount of biting of the locking portion into the outer circumferential surface of the connecting pipe increases in the portion facing the slit where the diameter reduction rate is small, and on the other hand, in the portion near the slit where the diameter reduction rate is large, The amount of bite of the locking portion into the outer circumferential surface of the connecting tube is reduced, and the liquid stopper member restrains the connecting tube with a substantially uniform locking force over the entire circumferential surface.

As a result, there is no risk of local force acting on the end of the connecting tube inserted into the 2m hand body and damaging the connecting tube. Further, since the retaining member restrains the connecting pipe with a uniform locking force, there is no risk that the retaining member will tilt with respect to the connecting pipe and the connecting pipe will come off from the retaining member.

4 Pa's buds■ FIG. 1 is a sectional view showing an example of the pipe joint of the present invention.

Fig. 2 is a front view showing an example of the retaining member, Fig. 3 is a sectional view taken along the line ■-■ in Fig. 2, and Fig. 4 is an IV in Fig. 2.
5 and 6 are cross-sectional views of essential parts for explaining the operation of the pipe joint of the present invention, respectively.

lO...Joint body, 11...Opening, 30...
Retaining member 31...slit, 32...locking part,
40...Connecting pipe.

that's all

Claims (1)

[Claims] 1. The end of the connecting pipe has a cylindrical shape that is inserted through an opening at one end, and the inner peripheral portion thereof has a diameter that gradually decreases as it approaches the opening. A joint body having a conical tapered portion, and a slit formed in a part of the circumference so that a connecting pipe inserted into the joint body can be fitted onto the outside of the joint body. a retaining member that is divided into annular shapes and has a sawtooth-like locking portion around the entire inner circumference thereof, and the locking portion has a small cutting amount near the slit; A pipe joint characterized in that the size increases as the distance from the slit increases.