JPH0599389A - Branch joint joint, mounting pipe and branch connection structure - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a joint that does not increase propulsion resistance, can be easily set in the connection hole of the main pipe with a small insertion force, and does not come off from the main connection hole after setting. Then, by using this, a connection structure excellent in waterproofness and strength is realized. [Structure] Two or more elastic locking pieces 2c, 2c are formed on a spigot 2a provided at one end of a joint 1, and are curved so as to be located on the inner side of the joint toward the tip. The burrs 2d, 2d are provided on the outer surface of the tip of the locking piece.
Then, by inserting the spigot 4a of the mounting pipe 4 into the joint 1, the burrs 2d, 2d are formed on the inner surface side of the hole edge portion of the connection hole 3a of the main pipe 3.
While locking d, the joint 1 and the main pipe 3 are sealed with a rubber packing 5 provided on the outer circumference of the joint opening.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a branch joint for use in joining a mounting pipe to a main pipe of a sewer or the like buried in the ground so as to intersect the main pipe, a mounting pipe, and Regarding connection structure.

[0002]

2. Description of the Related Art For example, an attachment pipe is installed between a main sewer pipe pre-embedded in the ground and a house on the ground to allow waste water from the house to flow to the main sewer pipe. This type of mounting pipe is mounted so as to intersect the main pipe in the ground, and in that case, conventionally, the mounting pipe was generally laid by cutting the ground. However, in recent years, the so-called non-excavation method is often adopted because the excavation space cannot be sufficiently obtained in many cases.

In this non-open cutting method, the mounting pipe is propelled to a predetermined position and connected without cutting the ground,
In that case, how to connect the mounting pipe to the main pipe smoothly and surely, and how to secure water stopping property and strength at the connecting portion becomes a problem. Therefore, as a means for dealing with such a problem, for example, the actual development 54
A joint for joining a branch portion as shown in Japanese Patent No. 148931 has been proposed. This is because, in a joint having a receiving end at one end and an outlet at the other end, an elastic locking piece is formed at the opening, and the tip of the locking piece is bent outward to provide a burr. A collar having an outer diameter larger than the diameter of the connecting hole of the main pipe is provided on the outer periphery between the mouth and the spigot.

According to this, when the spigot of the joint is inserted into the connection hole of the main pipe, the burr of the elastic locking piece is caught on the hole edge portion of the connection hole so that the joint is fixed to the main pipe connection hole. .. That is, by connecting the mounting pipe to the main pipe through this joint, the strength of the connecting portion can be secured.

[0005]

However, in the conventional joint as described above, the burr of the elastic locking piece is merely caught on the hole edge portion of the main pipe connecting hole when set in the main pipe. Therefore, when a bending force is applied to the joint, the locking piece may separate from the hole edge portion of the main pipe and the entire joint may come off from the main pipe.

Further, since the outer diameter of the tip portion of the joint, that is, the above-mentioned burr portion is made larger than the hole diameter of the main pipe connecting hole so as to be hooked on the hole edge portion of the main pipe connecting hole, when installing in the main pipe connecting hole. It is necessary to temporarily reduce the diameter of the burr and insert it, and if the mounting position is a little misaligned,
The tip of the burr may come into contact with the outer wall surface of the main pipe and break.

Further, when the joint is inserted into the ground in a non-open cut state, the flange at the outer periphery of the joint serves as a propulsion resistance, which imposes a heavy load on the mounting pipe and the joint and may damage them. .. The present invention addresses the above-mentioned problems in the related art, can be easily set in the connection hole of the main pipe with a small insertion force without increasing the propulsion resistance, and the main pipe connection hole can be set after the setting. We provide a joint that does not come off from the pipe and a mounting pipe that is suitable for mounting to the main pipe through this joint, and by combining these, we have realized a branch connection structure with excellent water-stopping performance and strength. The purpose is to do.

[0008]

In order to achieve the above object, the invention according to claim 1 of the present application (hereinafter referred to as the first invention)
Is a branch joint for use in joining a mounting pipe to a main pipe buried in the ground so as to intersect with the main pipe, and is configured as follows. That is, at one end of the joint, an outlet having an outer diameter of the tip portion that is smaller than or substantially equal to the hole diameter of the connection hole of the main pipe is provided, and the inlet is located on the inner side of the joint toward the tip. To form two or more elastic locking pieces that are generally curved. Then, when the mounting piece is inserted into the outer surface of the tip of the elastic locking piece and the locking piece is expanded to the outside of the joint, it is locked to the inner surface side of the hole edge portion of the connection hole of the main pipe. Further, a water blocking member that seals between the joint and the main pipe when the joint is set in the main pipe connection hole is provided at a step portion between the spigot and the joint main body.

The invention according to claim 2 of the present application (hereinafter, referred to as the second invention) is a mounting pipe connected to the main pipe through the above-mentioned joint, and is provided with an opening at one end. The tip portion of the is configured to have a shape corresponding to the shape of the connection hole of the main pipe so that it does not project into the main pipe when it is attached to the main pipe. Furthermore, the invention according to claim 3 of the present application (hereinafter, referred to as the third
The invention) is a branch portion connecting structure in which the mounting pipe of claim 2 is attached to the main pipe buried in the ground through the joint for joining branch portions of claim 1, and is configured as follows.

That is, after inserting the spigot of the joint into the connection hole of the main pipe, the spigot of the mounting pipe is inserted into the joint, and the tip end of the spigot of the mounting pipe is connected to the joint spigot. By positioning the elastic locking piece on the inner surface side, the burr at the tip of the elastic locking piece is locked on the inner surface side of the hole edge portion of the main pipe connecting hole.
Then, the joint and the main pipe are sealed by the water blocking member provided in the step portion between the joint spigot and the joint body.

Here, the body portion of the joint, that is, the joint body, is preferably cylindrical so that it can be easily connected to the mounting pipe. However, the joint end shape of the mounting pipe and the joint end shape of the joint body are different. It is only necessary that they are the same, and the shape is not particularly limited to a cylindrical shape. Also, for the joint end for the fitting pipe in this joint body, in the case of adhesive joining, the outer diameter on the joint body side may be adjusted so as to match the inner diameter of the joint end for the fitting pipe. The rubber packing may be set on the joint body side.

On the other hand, the shape of the end of the joint body on the main pipe connecting side, that is, the shape of the tip of the spigot, must be a shape that follows the outer circumference of the main pipe. Therefore, when the joint is viewed from the direction corresponding to the axial direction of the main pipe in a predetermined set state, the diameter of the curved surface that is the end face of the end of the spigot should be the same or substantially the same as the outer diameter of the main pipe. It is necessary to form it.

Further, the burr on the outer surface of the elastic locking piece is formed in a tapered shape or a shape having an arc-shaped cross section on the outside close to the tapered shape so that the burr can be easily inserted into the connection hole of the main pipe. Is preferred. This type of burr may be provided on the entire circumference of the joint or may be provided on a part thereof.
However, in order to stabilize the joint when the joint is set in the connection hole of the main pipe, it is preferable to provide a burr at the portion corresponding to the hole edge portion located in the main pipe axial direction in the connection hole (see FIG. 1 described later). And FIG. 2). This is because, particularly when the diameters of the main pipe and the joint are not so different from each other, the inclination becomes relatively large at the hole edge portion located in the direction orthogonal to the main pipe axial direction, and the burr is less likely to be caught. is there.

Further, the burr is bent inward, and the diameter of the tip of the burr on the outer peripheral side is set to be smaller than or about the same as the diameter of the connection hole of the main pipe. Further, as the joint body as described above, it is preferable to use an injection molded product made of a material such as vinyl chloride resin, polyethylene, polypropylene or the like, in consideration of the corrosion resistance and the ease of manufacturing. In that case, in order to increase the strength, glass fiber or the like may be wrapped around the outer peripheral surface of the joint body for reinforcement.

On the other hand, the shape of the water shut-off member is formed in a ring shape along the outer surface of the spigot of the joint body, and the tip side is made into the outer surface shape of the main pipe so as to follow the outer surface of the main pipe when the joint is connected. It is preferable to match. However, since an elastic body such as a rubber packing is usually used as such a water blocking member, in that case, it is not always necessary to accurately match the tip end side to the outer surface shape of the main pipe.

Since this type of water blocking member is in direct contact with the outer surface of the main pipe, it has a shape that follows the outer surface of the main pipe, or it is elastically deformed when pressed against the outer surface of the main pipe. It is preferable to have a sufficient thickness so that
In this case, the thickness is required to be at least as large as the gap generated between the outer surface of the main pipe and the joint body when the joint is set in the connection hole of the main pipe.

The cross-sectional shape of the water blocking member may be circular, polygonal, oval or the like, and a conventionally used O ring may be used. Further, the material thereof is preferably one having a high cushioning property (elasticity) or high adhesiveness (for example, butyl rubber) so that sufficient water stopping performance is exhibited when pressed against the outer surface of the main pipe.

[0018]

According to the above construction, the elastic locking piece at the joint opening is curved inward of the fitting, and the outer diameter of the tip of the opening, that is, the outer diameter of the burr on the outer surface of the elastic locking piece is the main pipe. Since it is smaller than or almost equal to the connection hole of the main pipe, the joint spigot can be inserted into the connection hole of the main pipe with an extremely small force (for example, when the outer diameter of the burr is smaller than the diameter of the connection hole. Has zero insertion force).

Then, after inserting and setting the spigot of the joint into the main pipe connecting hole, the fitting pipe is inserted into the joint, and the tip end of the spigot in the fitting pipe is elastically locked at the spigot. When it is located inside the piece, the elastic locking piece that is curved inward is pushed outward from the inside by the mounting tube, and as a result, the burr on the outer surface of the elastic locking piece is the edge of the connection hole. It is locked and fixed on the inner surface side of.

Therefore, after the fitting pipe is connected to the main pipe connecting hole through the joint in this way, there is no possibility that the joint will separate from the main pipe connecting hole except when the joint base material is broken. As a result, the main pipe and the mounting pipe are firmly and reliably connected via the joint. Further, at this time, the water blocking member provided in the step portion between the joint body and the outlet is sandwiched at least between the end surface (step forming surface) on the outlet side of the joint body and the outer surface of the main pipe. By closely contacting them in the compressed state, the joint and the main pipe are reliably sealed, so that sufficient water shutoff is secured between the joint and the main pipe.

Further, in this way, the main pipe and the joint are mechanically joined with the water blocking member interposed therebetween, while the joint of the mounting pipe is inserted and connected into the joint, so that, for example, the mounting pipe Even if a force in the compression direction or a bending force acts on the attachment pipe branch portion due to the ground displacement or the like after installation, those forces are absorbed by the flexibility of the water blocking member. As a result, it is possible to avoid the occurrence of cracks at the branch portion of the mounting pipe, and to prevent the deterioration of the water-stop performance and the occurrence of water leakage.

Further, in the above-mentioned joint, since the convex portion such as the brim which increases the propulsion resistance is not provided, the propulsion resistance does not increase. Therefore, it can be smoothly propelled, and damage to the mounting pipe and the joint at the time of propulsion can be prevented.

[0023]

EXAMPLES Examples of the present invention will be described below. As shown in FIG. 1, a joint 1 according to this embodiment has a stepped cylindrical joint body 2. This joint body 2 has an outer diameter larger than the hole diameter of the connection hole 3a of the main pipe 3, and has a spigot 2a for the main pipe connection hole 3a at one end thereof.

The outlet 2a has an outer diameter at its tip end slightly smaller than that of the connecting hole 3a so that it can be easily inserted into the main connecting hole 3a. Since the slits 2b ... 2b are formed in the tip end side in the axial direction, the two elastic locking pieces 2 facing each other in the illustrated example.
c, 2c are formed. These elastic locking pieces 2c,
2c is generally curved so as to be positioned on the inner side of the joint as it goes to the tip, and burrs 2d and 2d are provided on the outer surface of the tip portion thereof, respectively.

Each of the burrs 2d has a tapered cross section in the axial direction. Then, as shown in FIG. 2, the insertion port 4a provided at one end of the mounting tube 4 is inserted in the joint 2 in the direction of arrow A, and the tip of the insertion port 4a is elastically locked as shown in FIG. When the elastic locking pieces 2c, 2c are opened by the mounting pipe insertion opening 4a on the inner side (axial center side) of the pieces 2c, 2c, the respective burrs 2d, 2c.
d is engaged with the inner surface of the hole 3a of the connection hole 3a, that is, the inner surface of the main pipe 3.

Here, since the tip 4b of the spigot 4a of the mounting pipe 4 has a shape corresponding to the shape of the main pipe connecting hole 3a, that is, a similar shape, at the time of mounting to the main pipe 3 The tip 4b of the outlet is configured so as not to project inward of the main pipe. Further, an annular rubber packing 5 having a predetermined width is provided on the outer periphery of the spigot 2a of the joint 1 at the step portion on the proximal end side of the spigot. Then, the joint 1
When the burr 2d, 2d is locked to the inner surface of the hole edge portion of the connection hole 3a, the step portion and the connection hole 3 are set.
The rubber packing 5 is sandwiched between the outer surface of the hole edge portion of "a" and closely adhered thereto in a compressed state, so that the joint 1 and the main pipe 3
The space between and is sealed.

The overall shape of the tip of the joint outlet 2a is also
Like the tip portion 4b of the mounting pipe 4, it is formed so as to correspond to the hole shape of the connection hole 3a of the main pipe 3. Further, particularly in this embodiment, as shown in FIG. 3, a seal member 6 made of, for example, rubber or synthetic resin is attached to the outer peripheral joints of the joint 1 and the mounting pipe 4, whereby the joint 1 and the mounting pipe 4 are mounted.
The outer peripheral joint is sealed.

The joint 1 and the attachment pipe 4 are attached to the main pipe 3 at predetermined positions as follows. First, the position of the main pipe 3 buried in the ground is detected by a known technique using electromagnetic waves, and then the propulsion unit and the boring are placed at a predetermined position on the ground which is the starting point of the mounting pipe 4 by surveying. The machine is set to a predetermined state and the drive motor is connected to the boring machine.

Next, in this state, the drive motor rotates the excavating blade in the boring machine through the wire and the rotating rod, and at the same time, the propulsion machine uses the boring machine as a lead conductor to predetermined the main pipe 3 in the ground. Move forward to position. Then, while excavating the ground in this manner, the sheath pipe is connected to the rear portion of the front conductor and the ground conductor is propelled in the same manner as in the case of the front conductor. In this case, the earth and sand generated by excavating the precursor is removed by a known method such as supplying water to make it muddy and then sucking it with a pump.

By repeating the above operation, the tip of the front conductor reaches the outer surface of the main pipe 3. After arrival, pull out all the conductors and accessories to the ground, insert a drilling machine from the ground instead, drill the pipe wall of the main pipe 3 with this drilling machine, and cut it to the specified diameter as shown in FIG. The connection hole 3a is formed. After forming the connection hole, the boring machine is pulled out, the joint 1 and the mounting pipe 4 are inserted into the sheath pipe in this order from the ground, and first, the insertion hole 2a of the joint 1 is inserted into the connection hole 3a of the main pipe 3 by a predetermined amount. At this time, 2
In a, the elastic locking pieces 2c, 2c are curved inward and the outer diameter of the tip end portion thereof is smaller than the hole diameter of the connection hole 3a, so that the insertion port 2a is extremely easily inserted into the connection hole 3a. be able to.

Next, the insertion port 4a of the attachment pipe 4 is inserted into the joint 1, and the tip of the attachment pipe insertion port 4a is positioned inside the elastic locking pieces 2c, 2c of the joint insertion port 2a. By doing so, the elastic locking piece 2 that was initially curved inward
c and 2c are pushed outward from the inside by the attachment pipe inlet 4a, and the diameter is expanded by a predetermined amount. As a result, the elastic locking piece 2
The burrs 2d and 2d on the outer surfaces of c and 2c are the connection holes 3a.
It is locked and fixed to the inner surface side of the hole edge portion of. This allows
The main pipe 3 and the mounting pipe 4 are securely and firmly connected via the joint 1.

When the mounting pipe 4 is inserted, for example, an adhesive is applied in advance to the outer surface of the spigot 4a, the inner surface of the joint 1 or the like, so that the joint 1 and the mounting pipe 4 can be joined more reliably. Can be something. At this time, since the rubber packing 5 having a predetermined thickness is provided at the step between the joint opening 2a and the joint body 2, the rubber packing 5 connects the joint body 2 or the outlet 2a to the main pipe. It is sandwiched between the hole 3a and the edge portion of the hole 3a, compressed, and adheres thereto. As a result, the joint 1 and the main pipe 3 are reliably sealed, and a sufficient waterproof property is secured between them.

Furthermore, since the main pipe 3 and the joint 1 are joined while the rubber packing 5 is sandwiched in this way, the fitting pipe 4 is inserted and joined to the opening 2a of the joint 1. Even if a force in the compression direction or a bending force acts on the mounting pipe branch portion due to, for example, ground displacement after installation of the mounting pipe, those forces are absorbed by the flexibility of the rubber packing 5. As a result, it is possible to avoid the occurrence of cracks at the branch portion of the mounting pipe, and to prevent the deterioration of the waterproof performance, that is, the occurrence of water leakage.

After connecting the mounting pipe 4 to the main pipe 3 as described above, the filler pipe of the mortar is injected between the sheath pipe and the mounting pipe 4 and the sheath pipe is pulled out to carry out the construction. Complete. In the above embodiment, the joint 1 having the inlet 2a at one end is used, but the joint according to the present invention is not limited to this, and the joints at both ends are not provided as shown in FIG. It may be a joint 11 having ports 12a, 12a '. Further, in the joint 11 according to the second embodiment, two elastic locking pieces 12c, 12c are arranged facing each other at the one opening 12a which is an insertion portion into the main pipe. The burr 1 on the outer surface of the locking pieces 12c, 12c
2d and 12d are projected.

[0035]

As described above, according to the present invention, the joint opening can be easily inserted into the connection hole of the main pipe, and after the insertion, the mounting pipe is inserted into the joint opening. The joint is securely fixed so that it will not come out of the main pipe connection hole. Therefore, the main pipe and the mounting pipe are securely and firmly connected to each other through this joint.

In addition, after the connection, not only the water between the joint and the main pipe is sufficiently stopped by the water stop member, but also the force in the compression direction or the bending force acts on the connection part due to the ground displacement, for example. However, since those forces are absorbed by the flexibility of the water blocking member, it is possible to avoid the occurrence of cracks at the branch portion of the mounting pipe, and to prevent the deterioration of the water blocking performance and the occurrence of water leakage.

Further, in the joint according to the present invention, the propulsion resistance does not increase because the convex portion such as the brim is not provided on the outer periphery. Therefore, it can be smoothly propelled, and damage to the mounting pipe and the joint at the time of propulsion can be prevented.

[Brief description of drawings]

FIG. 1 is a partially longitudinal front view showing a joint according to a first embodiment of the present invention.

FIG. 2 is a partially longitudinal front view showing a state before connecting a mounting pipe to a main pipe through the joint.

FIG. 3 is a partially longitudinal front view showing a state in which an attachment pipe is connected to a connection hole of a main pipe via a joint.

FIG. 4 is a partially longitudinal front view showing a joint according to a second embodiment of the present invention.

[Explanation of symbols]

 1, 11 ... Joint for joining branch part, 2 ... Joint body, 2a, 12a ... Spigot, 2c, 12c ... Elastic locking piece, 2d, 12d ... Burr, 3 ... -Main pipe, 3a ... Connection hole, 4 ... Mounting pipe, 4a ... Mounting pipe spout, 4b ... Mounting pipe tip, 5 ... Water blocking member (rubber packing ).

Claims (3)

[Claims] 1. A branch joint for use in joining a mounting pipe to a main pipe buried in the ground so as to intersect with the main pipe, the outer diameter of a tip end being at one end. Is provided with a spigot that is smaller than or approximately equal to the diameter of the connection hole of the main pipe, and the spigot has two or more parts that are generally curved so that they are located on the inner side of the joint toward the tip. Elastic locking piece is formed on the outer surface of the tip of the locking piece, and when the locking piece is expanded to the outside of the joint by inserting the mounting pipe, the inner surface of the hole edge portion of the connection hole of the main pipe There is a burr that locks to the pipe, and the step between the spigot and the joint body has a water stop that seals between the joint and the main pipe when the joint is set in the main pipe connection hole. A joint for joining a branch portion, which is provided with a member. 2. A mounting pipe which is mounted so as to intersect with a main pipe buried in the ground, wherein an end portion is provided with a spigot, and the tip of the spigot is a main pipe. A mounting pipe having a shape corresponding to a hole shape of a connection hole of the main pipe so as not to project into the main pipe when the pipe is attached to the pipe. 3. A branch portion connecting structure in which the mounting pipe according to claim 2 is attached to the main pipe buried in the ground via the branch joint joint according to claim 1. After inserting the spigot of the joint into the connection hole of, the spigot of the mounting pipe is inserted into the joint, and the tip of the spigot of the mounting pipe is an elastic locking piece at the joint spigot. The burr on the outer surface of the tip end portion of the locking piece is locked to the inner surface side of the hole edge portion of the main pipe connecting hole while being positioned on the inner surface side of the water stop member between the joint and the main pipe. Branch connection structure characterized by being sealed by.