JP2002071064A - Seismic joints for sewer pipes - Google Patents

Abstract

(57) [Summary] (Modifications required) [Problem] To improve the wasteful structure of a sewer pipe when the water supply pipe is applied to the sewer pipe as it is to make it a seismic joint. As an issue. SOLUTION: An insertion port 3 formed at an end of the other pipe 1 is inserted into a receiving port 2 formed at an end of one pipe 1 through a rubber ring 4 for sealing, and connected. The inner wall of the receiving opening 2a of the receiving groove 5 of the sealing rubber ring 4 formed on the inner surface of the receiving port 2 has a tapered surface 5a whose diameter decreases toward the opening. A lock ring 6 having a tapered outer surface having a larger inclination angle than the tapered surface 5a is housed in contact with the tapered surface 5a, and a rubber ring 4 for sealing is disposed on a receiving inner side 6b of the lock ring 6 for sealing. When the insertion projection 8 that moves through the inner surface of the rubber ring 4 engages with the lock ring 6, the lock ring 6 is pressed by the insertion projection 8, rotates torsionally, and winds around the outer surface of the insertion 3. It is fixed to prevent slipping out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seismic joint for sewage pipes.

[0002]

2. Description of the Related Art Conventionally, as a structure of a joint of a seismic pipe for water supply, for example, a rubber ring for sealing is mounted on an opening end portion of a receiving port, and a lock ring is mounted on an inner periphery deeper than the receiving port. , A projection is formed on the outer periphery of the insertion port, and the projection is configured to engage with the lock ring from the back side of the reception port, so that the inside of the reception port reaches a position where the front end of the insertion port contacts the back end of the reception port. In addition to allowing the insertion of the insertion port, the insertion port can be pulled out until the projection of the insertion port engages with the lock ring of the receiving port. Some have a total allowable length of 2% of the pipe length.

When such a pipe for water supply is used as a pipe for sewage, usually, a sewage joint is inserted until the tip of the insertion hole hits the back end of the receptacle, and is inserted between the insertion end and the back end of the reception port. Since a gap is not usually provided in the space, there is a problem that the length of the contracted portion becomes longer than necessary by an allowable length of expansion and contraction.

Further, in these seismic pipe joints, since a lock ring or the like is usually disposed at a position deeper than the sealing rubber ring at the receiving end, when this is used as a sewer pipe joint, sewage in the pipe is reduced. There is a problem that the lock ring portion directly enters the lock ring portion and there is a concern that the lock ring is corroded by sewage.

It has been considered that a welding bead is provided on the outer surface of the insertion hole as a structure of the insertion protrusion and this is used as an engaging member for the lock ring. However, the surface of the welding bead has a smooth curved surface. In many cases, when the insertion hole comes out and the lock ring catches on the weld bead, the lock ring gets on the weld bead without getting caught, and the lock link is gradually expanded along the curved surface, and the detachment prevention function is sufficient There is also a problem that it may not be exhibited.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above problems and to improve the useless structure of the joint portion, and to make the sewer pipe a seismically resistant pipe joint. Make it an issue.

[0007]

According to the present invention, there is provided a seismic joint for sewage pipes which seals an insertion hole formed at an end of one pipe with an insertion hole formed at an end of the other pipe. A pipe which is inserted and connected by inserting a rubber ring, wherein the inner wall of the storage groove of the sealing rubber ring formed on the inner surface of the receiving port has a smaller diameter toward the opening side. Tapered surface,
A lock ring having a tapered outer surface having a larger inclination angle than the tapered surface is housed in contact with the tapered surface, a rubber ring for sealing is arranged on the back side of the receiving end of the lock ring, and an outer peripheral projection at the front end of the insertion port. The lock ring can be pressed so as to press the tapered surfaces against each other by the sealing rubber ring which moves together with the insertion direction in the exit direction by engaging with the insertion ring, and further the insertion projection which moves through the inner surface of the sealing rubber ring. When the part is engaged with the lock ring, the lock ring is pushed by the insertion projection and is rotated by the difference of the taper angle, and the tapered surface is brought into contact with no gap so that it is tightly wound around the outer surface of the insertion hole. This is intended to prevent slipping out.

That is, according to the seismic joint for sewer pipes of the present invention, the lock ring for preventing the escape of the insertion opening is integrated into the storage groove portion of the sealing rubber ring.
There is no need to provide a lock ring storage groove, centering rubber, or the like at a position independent of the rubber ring for sealing, and the structure is simplified.
Further, since the lock ring is installed on the opening side of the sealing rubber ring, it is protected from internal sewage.

Since there is no need to provide a lock ring housing groove on the inner surface of the receiving port, the length of the joint can be reduced.
Furthermore, since the insertion end can be abutted against the back end of the receiving end, there is no need to consider a margin for shrinkage.

[0010] Further, since the lock ring makes the tapered surface of the inner surface of the receiving port come into contact with the tapered surface having a larger inclination angle, when the lock ring comes into contact with the insertion projection by the welding bead, it is pressed.
Due to the force, the lock ring is first twisted by the difference in taper angle, and the tapered surfaces are in contact with each other without any gap. This prevents the diameter of the lock ring from expanding, and then the twisting causes the contact of the lock ring to the weld bead. It changes to an acute angle direction, and it can be prevented from climbing over a weld bead having a curved outer surface. Further, the axially moving force is also divided as a component force in the radial direction by the radial slope, and this becomes a force for tightening the insertion opening, and thus becomes a detachment preventing force.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the seismic joint for sewage pipes of the present invention will be described. FIG. 1 is a partially cut-away side view of a sewer pipe seismic joint according to an embodiment of the present invention;
FIG. 2 is an enlarged cross-sectional view showing a broken portion of FIG.

In FIG. 1, reference numeral 1 denotes a sewage pipe, which in this embodiment is a metal pipe such as a ductile cast iron pipe. This sewer pipe 1 has a receiving port 2 formed at one end and an insertion port 3 at the other end, and the other pipe 1 is connected to the receiving port 2 of one of the sewer pipes 1.
Can be connected by inserting the insertion port 3 of.

A receiving groove 5 for a sealing rubber ring is formed on the inner surface of the receiving port 2 on the side of the receiving port opening end 2a, and a sealing rubber ring 4 is stored therein. The inner wall 5a of the sealing rubber ring housing groove 5 on the tube receiving opening side has a tapered surface whose diameter decreases toward the receiving opening 2a.

A lock ring 6 having a tapered outer surface 6a is housed in the housing groove 5 in contact with the tapered surface 5a. The tapered surface 5a and the tapered outer surface 6a
As shown in an enlarged manner in FIG. 2, the inclination angle θ of the tapered outer surface 6a is, for example, about 5 degrees larger than the inclination angle α of the tapered surface 5a.

The lock ring 6 is broken into one piece (not shown) by a metal ring, and the diameter of the crack can be elastically expanded and reduced. The receiving opening side of the sealing rubber ring 4 is capable of pressing the receiving deep side surface 6 b of the lock ring 6, and in the illustrated example, is pressed via the centering ring 7. The centering ring 7
Is not always necessary, and the sealing rubber ring 4 and the lock ring 6 may be brought into direct contact as shown in FIG.

The sealing rubber ring 4 has a tapered surface with a front surface 4a having a cross-sectional shape inclined toward the back of the tube so that the insertion opening 3 and the insertion projection 8 can be easily inserted. Further, a bottom protrusion 4b is formed to engage with the bottom surface of the storage groove 5 so that the rubber ring 4 for sealing is not drawn into the receiving hole when the insertion opening 3 is inserted.

An insertion opening 3 having an insertion projection 8 made of, for example, a weld bead on the outer periphery is connected to the front end 3a by a receiving end 2b.
It is inserted until it is hit by. In the above embodiment, the position where the insertion projection 8 is provided is located inside the pipe end 3a of the insertion opening 3 by a distance t substantially equal to the width T of the sealing rubber ring 4.

This is because the outer surface of the insertion port 3 is sealed by the sealing rubber ring 4 when the insertion projection 8 comes out and engages with the lock ring 6. The distance S between the insertion projection 8 and the lock ring 6 when the insertion opening 3 is inserted is:
For example, it is 1.5% of the pipe length. This is to allow extension for preventing separation.

Next, the assembly and seismic operation of the seismic joint for sewer pipes of the present invention will be described. First, the sealing rubber ring 4 is stored in the storage groove 5 in the receiving port 2, and then the lock ring 6 is installed on the opening end side of the sealing rubber ring 4.

Next, if necessary, a lubricant is applied to the inner peripheral surface of the sealing rubber ring 4 and the outer peripheral surface of the insertion opening 3 to receive the insertion opening 3 having the insertion projection 8 as shown in FIG. 5, the insertion projection 8 is forcibly passed through the lock ring 6 and the sealing rubber ring 4 as shown in FIG. 5, and then, as shown in FIG. 2 or FIG. The insertion opening 3 is inserted until the pipe end 3a contacts the reception end 2b.

This completes the pipe connection. Under normal conditions,
As shown in FIG. 1 to FIG. 3, the insertion port 3 and the reception port 2
a and the back end 2b are in contact with each other, so that solids contained in the sewage are prevented from flowing between the inner surface of the receiving port 2 and the outer surface of the insertion port 3, and the sealing function of the sealing rubber ring 4 Outflow of sewage in the pipe and outflow of groundwater and rainwater outside the pipe into the sewage pipe are prevented.

Next, when a large axial external force is applied to the sewer pipe 1 due to the earthquake, and the insertion port 3 moves in the escape direction as shown by an arrow in FIG. 6, the insertion projection 8 becomes the sealing rubber ring 4.
And presses the sealing rubber ring 4 in the direction of the receiving opening 2a.

With this force, the lock ring 6 presses the tapered surface 6a against the tapered surface 5a on the inner surface of the storage groove, and the contact of the tapered surface acts to reduce the diameter of the lock ring. Numeral 6 is fixedly wound around the outer surface of the insertion opening 3.

Furthermore, when the external force is large, the projection 8 moves through the inner surface of the sealing rubber ring 4, but the projection 8 is a small projection compared to the size of the sealing rubber ring 4. There is almost no effect on the sealability, and the sewage does not leak to the outside.

When the moving distance becomes S, the insertion projection 8 comes into contact with the lock ring 6 as shown in FIG.
The lock ring 6 is pressed as shown in an enlarged manner in FIG. At this time, the lock ring 6 receives the force F in the disengagement direction and twists as shown by the arrow B in FIG.
a and 6a are brought into contact with each other without a gap.

Therefore, this contact causes the lock ring 6
8B, the inner corner 6c of the lock ring 6 contacts the insertion projection 8 at an acute angle as shown in FIG. 8 is securely held, and the slipping force against the slipping force prevents slipping out.

Accordingly, even with the insertion projection 8 having a degree of welding bead arrangement, it is possible to sufficiently prevent the joint portion from being detached due to ground fluctuation caused by a large earthquake. Further, even after the insertion port has been moved in this way, the outer surface of the insertion port 3 and the inner surface of the receiving port 2 are sealed by the rubber ring 4 for sealing, so that the lock ring 6 is not immersed in sewage. There is no drainage of sewage or inflow of external groundwater or rainwater.

[0028]

As described above, the seismic joint for sewage pipes of the present invention has a structure in which the lock ring for preventing disengagement is integrally incorporated into the rubber ring portion for sealing. Since a groove is not required, and the allowable expansion / contraction amount S only needs to be in the direction of extension, there is an effect that both can be combined to shorten the shape of the joint.

Further, members required for preventing detachment, such as a lock ring, are protected from sewage by rubber for sealing, so that long-term durability can be achieved. And even if the lock ring is a projection by a weld bead, when the lock ring comes out, it is twisted and displaced by contact with the insertion projection, so that the posture becomes such that the corners bite into the insertion projection. This has the effect of securely engaging with the lock ring and preventing slipping out.

[Brief description of the drawings]

FIG. 1 is a partially broken side view of a seismic joint for sewage pipes.

FIG. 2 is an enlarged cross-sectional view showing a broken portion of FIG.

FIG. 3 is a cross-sectional view of another configuration example of the seismic joint for sewage pipes.

FIG. 4 is a cross-sectional view showing a state where an insertion opening of the seismic joint for sewage pipes is inserted.

FIG. 5 is a cross-sectional view showing a state in which an insertion projection portion of the seismic joint for sewage pipes is inserted.

FIG. 6 is a cross-sectional view showing a state in which an insertion hole comes out of a sewer pipe seismic joint after connection.

FIG. 7 is a cross-sectional view showing a state in which the opening further comes out of the seismic joint for sewer pipe after connection.

FIGS. 8A and 8B are enlarged cross-sectional views of a main part showing engagement between the insertion protrusion and the lock ring, where FIG. 8A is a view when the lock ring is engaged with the insertion protrusion, and FIG. Shows a state in which the lock ring has been twisted after the rotation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drain pipe 2 Reception opening 2a Reception opening end 2b Reception opening end 3 Insertion opening 3a Insertion end surface 4 Sealing rubber ring 5 Sealing rubber ring storage groove 7 Centering rubber 8 Inserting projection

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masahiko Kato 2-26, Ohama-cho, Amagasaki-shi, Hyogo F-term in Kubota-Mukogawa Works (reference) 2D063 BA01 BA26 BA27 3H015 FA06

Claims (1)

[Claims] 1. A tube in which an insertion hole formed at an end of the other tube is inserted into a receiving hole formed at an end of one tube via a rubber ring for sealing, and is connected. Wherein the inner wall of the receiving groove of the sealing rubber ring formed on the inner surface of the receiving port has a tapered surface whose diameter decreases toward the opening side, and the tapered shape has a larger inclination angle than the tapered surface. A lock ring having an outer surface is housed in contact with the tapered surface, and a rubber ring for sealing is arranged on a back side of a receiving port of the lock ring,
The lock ring can be pressed so that the tapered surfaces press against each other by the sealing rubber ring that moves together with the insertion port in the exit direction by engaging the outer peripheral projection of the insertion port tip with the engagement,
Further, when the insertion protrusion that moves through the inner surface of the sealing rubber ring engages with the lock ring, the lock ring is pushed by the insertion protrusion and twists and rotates by a difference in taper angle, so that the taper surface has a gap. A seismic joint for sewage pipes, which is prevented from expanding by preventing abutment from coming out of the insertion hole by making contact with the insertion protrusion without fail.