JP3328543B2 - Outer auxiliary pipe member for manhole - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer sub pipe member for a manhole, and more particularly to an inner or outer sub pipe member for a concrete manhole.

[0002]

2. Description of the Related Art In general, in a concrete manhole installed for connecting a step at a steep surface gradient in a mountainous area, for example, a drainage inflow pipe is provided directly on a side wall of the manhole and released. When the waterfall falls, the sewage scatters and adheres to the side walls, and the sewage accumulates on the invert and its surroundings, losing the function of the manhole, and the step between the inflow pipe and the outflow pipe. For example, when the height is 0.6 m or more, the bottom of the manhole, such as an invert, is scoured or eroded.

For this reason, a falling pipe having a diameter one size below the inflow pipe before or inside the manhole,
That is, an inner or outer sub pipe is provided to eliminate the above-mentioned waterfall and to prevent trouble in inspection and cleaning (Japanese Utility Model Laid-Open No. 59-18850, Japanese Utility Model Application Laid-Open No. 3-1116).
36, JP-A-8-326142, etc.).

A concrete manhole with an inner sub pipe is used for a horizontal pipe with almost no inclination of the inflow pipe, and a concrete manhole with an outer sub pipe has an inclined inflow pipe. It can be used for inclined pipes.

A typical example of such a concrete manhole with an external sub tube will be described.

In FIG. 3, this concrete manhole 50 is sized so that an operator can move up and down into the manhole using a footrest, and includes a manhole cover 51, a mouth ring 52, and a manhole slant. Wall 53, straight wall of manhole 54, wall rising section 5
5, an outer sub-tube 56, an inverter 57 and a bottom plate 58.

The concrete manhole 50 includes:
The inflow pipe 59 and the outflow pipe 60 are connected to each other with a step. The inflow pipe 59 is opened at the wall rising portion 55, and the outer sub pipe 56 is connected down.

The inflow pipe 59 is connected to the following joint. That is, in the structure shown in FIG. 4, it is called a sub-tube branch manhole joint 61, and a rubber ring socket (not shown) is formed on the inflow pipe side, and a spigot 62 is formed on the manhole side. 90 ° branch pipe made of PVC downward in the middle
3 are connected to form a joint.

[0009] The surface of the spigot 62 is subjected to FRP coating or surface sanding, and penetrates the wall rising portion 55,
It is fixed with a mortar coking 64.

The outlet 62 is usually opened and used as an outlet for overflow, but it is used as an outlet for checking the condition of the piping at the time of piping and for cleaning the inside of the piping. Is also used (see the above-cited publication).
Plugs are sometimes closed with plugs in consideration of the work inside the files.

The 90 ° branch pipe 63 is fastened and fixed by a line 65, and a color joint 66, a plain end straight pipe 67, a 90 ° curved pipe 68 and a downstream manhole joint 69 are attached to the 90 ° branch pipe 63. They are connected to form a PVC outer sub-tube 56.

However, in the conventional plug used for the spigot 62 of the sub-tube branch manhole joint 61, the tip and the 90
° There is a problem that a relatively large space is formed between the branch pipe 63 and the drainage or solid matter in the drainage, which is accumulated or deposited.

That is, for example, the aforementioned Japanese Utility Model Laid-Open No. 3-111
In Japanese Patent Publication No. 636, a plug including a cylindrical insertion portion and a flange-shaped pressing portion is used at the opening end of the spigot 62, so that a space is formed between the end surface of the insertion portion and the 90 ° branch pipe 63. In addition, the accumulation of solid matter is inevitable. In addition, when the operator opens the plug in the manhole, the manhole with the auxiliary pipe is originally required.
In this case, the sewage drains out to the worker because the inflow pipe is an inclined pipe, making the work difficult.

For this reason, for example, Japanese Utility Model Laid-Open No. 1-141849.
It is conceivable to employ a plug disclosed in Japanese Unexamined Patent Application Publication No. H11-163,873.

That is, according to the inner sub pipe described in this publication, a plug is fitted into an opening facing the inflow pipe, and the end face of the insertion portion of the plug is formed in a semicircular shape in plan view, and the plug is inserted into the drain. To prevent solids from accumulating.

However, such a plug is used for the inner sub pipe, and the inner sub pipe originally has disadvantages such as complicating the construction work of the outer sub pipe, increasing the construction cost, and further taking up the installation space. As it has been overcome, large concrete
Although it is convenient in the case of a manhole made of porcelain, there is a problem that if the manhole is reduced in size, it becomes obstructive to the manhole body where people enter and exit.

Moreover, in such a plug, since a large dead space is formed on the top side of the inflow pipe, the sewage pipe originally has a margin of about 100%, so that there is a possibility that the flow may be retained. There was a risk of contaminant attachment.

For this reason, the present inventors disclosed in Japanese Patent Laid-Open No. 8-32
This problem has been solved by developing a plug as disclosed in Japanese Patent No. 6142.

[0019]

However, the manhole joint (61) for branch pipe made of PVC described in Japanese Utility Model Laid-Open No. 3-111636 described above is generally disclosed in Japanese Patent Application Laid-Open No. H8-111816. As shown in -326142,
Although it is a PVC injection molded product, the injection molding method is originally a molding method suitable for mass production with small or thin wall precision, so the PVC injection molding of the sub-tube branch manhole joint (61) Due to the balance between the quality of the product and the concrete product of the manhole, it does not immediately respond to the advantages of the injection molding method, but rather is suitable for small- and medium-volume production with a large or thick, functional body. The blow molding method is considered to be advantageous, and the inventors of the present invention have made blow-molding a sub-tube branch manhole joint (61) made of PVC.
I thought of molding by a molding method.

In particular, when the manhole joint (61) for branching a sub-tube is to be formed by injection molding, an R is provided at the upper opening of the 90 ° branch pipe, that is, a curved bottom surface is formed. However, there is a problem that the forming die is complicated because an undercut occurs.

The present invention overcomes the drawbacks of the manhole with the external pipe as much as possible while forcing the flow to the external pipe to allow the solids to accumulate. It is a primary object of the present invention to provide an outer sub-tube member for a tool, and to make the outer sub-tube member blow-moldable.

[0022]

SUMMARY OF THE INVENTION In order to achieve the above object, the gist of the present invention is as follows. 1) A main pipe connecting portion for connecting a horizontal inflow pipe and a concave surface facing the inflow pipe are inserted. A joint body provided integrally with a branch pipe connecting portion downwardly between a plug receiving port for inserting a plug having an end face, and a downstream side opening at the branch pipe connecting portion toward the inversion of the manhole. Manho with color joints connecting external sub pipes
In the outer sub pipe member for pipes, the joint body is formed by blow molding in which an area is increased by a thickness reduction by a cold parison method using a PVC pipe, and the branch pipe connecting portion is formed. The corner portion on the side of the inflow pipe is constituted by a branch pipe section for the LT joint which is largely curved downward from the pipe line and is directed downward, and the branch pipe section for the LT joint on the side of the plug receiving port. The corner portion is formed by an orthogonal edge, and the branch pipe connecting portion is formed at a spout portion formed by cutting the tip after blow molding, and forming a curved surface at the bottom of the pipe. The collar is formed so as to be joined to the outer surface of the curved surface at the bottom of the pipe, and is bonded to the spout to secure the wall thickness to secure the connection strength in the outer sub pipe. 2) close the lower half of the plug, Sailing according to claim 1 which is a semi-cylindrical shape provided with a water passage section to the minute - is outside the secondary pipe member for Le.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to embodiments shown in the accompanying drawings. FIG. 1 is an overall vertical sectional view of an embodiment of the present invention, and FIG. 2 is an exploded view of a main part of FIG. 1. The same or equivalent parts as those in FIGS. Or, the explanation is omitted.

This embodiment is suitable for the outer sub tube of the concrete manhole shown in FIGS. 3 and 4.
In particular, it is convenient to use it for the PVC outer sub pipe member shown in FIG.

For example, the diameter of the inflow pipe (ie, sewage main pipe) is 200 mmφ, and the diameter of the falling pipe is 200 m.
Applies to dimensions of mφ.

1 and 2, a description will be given of a sub-tube branching manhole joint 1 according to the present embodiment.

This manhole joint 1 is a molded article made of vibrochloride using the cold parison method, and has an LT (90 °).
The joint body 2 has a large bent Y) shape.

The joint main body 2 has a main pipe connecting portion for connecting the inflow pipe 59 (also referred to as a main pipe side connecting portion in this specification).
The main ring connecting portion which is open at one of the rubber ring socket 3 and the wall rising portion 55 of the manhole body 4 and into which the plug 5 is inserted (in this specification, particularly, the main line connecting portion is Third
Is connected to the manhole body 4 but is referred to as a connection portion, and is also referred to as a main tube side connection portion).
And a branch pipe section for an LT joint, which is a branch pipe connection section (also referred to as a branch pipe side connection section in this specification), which is directed downward in the middle between the rubber ring port 3 and the plug port 6. 7 is comprised.

The outer periphery of the joint body 2 is subjected to sanding or the like so that the mortar coking 64 can fix the joint body 2 well.

The branch pipe section 7 for the LT joint is largely bent from the pipe of the inflow pipe 59 so as to be a downward pipe.
That is, a downwardly curved pipe bottom surface 8 (which forms an inner curved wall of the elbow and R = 70 mm) which forms a virtual 90 ° large-bend elbow is formed, and the drainage from the inflow pipe 59 is formed orthogonally without stagnation. And flows smoothly.

The plug 5 is a hollow injection-molded product.
It has dimensions of 00mmφ, 350mm in total tube length,
The insertion portion 9 includes a plug fixing portion 10 and a rectifying insertion portion 11.
Are separately injection-molded, and both are adhesively bonded.

The plug fixing portion 10 is provided with a fixing device 12 as described later. Further, on the tip end surface (insertion end surface) of the rectifying insertion portion 11, an R275mm which constitutes the virtual 90 ° large bending elbow is provided. The outer curved wall 13 is formed.

The extended outer curved wall 13 is an upper extended portion of the original 90 ° large bend Y, and has a concave surface extending from the upper opening end of the branch pipe portion 7 for the LT joint toward the inflow pipe 59. Like to wear.

Of course, the shape of the extended outer curved wall 13 is a vertical plane passing through the plug pipe axis, and a horizontal plane passing through the pipe axis is formed as described in Japanese Utility Model Laid-Open No. 1-141849. The semicircular shape along the upper opening of the branch pipe section 7 for the LT joint is formed so as to gradually rise toward the inflow pipe 59 so as to become zero. That is, the drainage flows into the LT joint branch pipe 7 without stagnation in the upper opening.

The fixing device 12 of the plug fixing portion 10 includes:
It is configured as follows. That is, a connecting pipe 15 having a joining portion on one end side for internally fitting and bonding to the rectifying insertion portion 11 and a joining portion for externally fitting the lid 14 on the other end side for adhesion.
And a lid 14. The lid 14 is composed of a rubber ring 16 and a handle 17, and the rubber ring 16 is closely fitted to the plug receiving port 6 to prevent the plug 5 from being pulled out. Both are sealing.

Of course, the configuration of the plug fixing portion 10 is as follows.
In order to manufacture at low cost using existing members, if mass production is to be performed, the fixing device 12 may be an integral injection molded product, or may be manufactured by a hand lay-up method of FRP. Further, the position of the lid 14 projects inward from the wall rising portion 55 in FIG. 1, but may be flush.

The plug 5 does not have to have a shape in which the plug receiving port 6 is completely closed, but may have a shape in which the lower half of the plug 5 is closed and a water passage is provided in the upper half, for example, a semi-cylindrical shape. .

Here, with respect to the joint body 2,
In particular, a manufacturing process by a blow molding method using a cold parison method will be described in detail.

As is well known, a tube or tube preformed by an extrusion method and cut to a predetermined length is used as a parison, and the drawing temperature (for example, about 12 in the case of PVC).
0 ° C.) and low pressure (usually ² to ²⁰ kg / cm ² , preferably 5 to 10 kg / m ²⁾ using a so-called cold parison method in which the tube is formed in a blow mold while holding both ends of the tube.
The joint body 2 is formed with a blowing pressure of kg / cm ² ).

At that time, although the degree of expansion differs depending on the shape of the molded product due to the biaxial stretching defined as the increase in area due to the decrease in thickness, although the blow molding is accompanied, For example, molded articles tend to be uneven in thickness, such as at corners where the parison is extremely elongated.

Therefore, in order to secure the thickness in the biaxial stretching, in general deep drawing blow molding, the depth (corresponding to the upper opening diameter D of the branch pipe portion 7 for the LT joint) is half the depth. (L
The maximum length is equivalent to the axial length L of the branch pipe portion 7 for the T-joint (refer to the Plastic Molding Technology Dictionary, published by Nihon Kogyo Shimbun, January 1994).

As is consistent with these reference materials, in the test of the joint main body 2 of the present embodiment, the axial length of the branch pipe part 7 was determined with respect to the upper opening diameter D200 mmφ of the branch pipe part 7 for LT joint. If L is not more than 100 mm, especially about 30%, the wall thickness cannot be secured, and the connection strength with the color joint 19 cannot be obtained.

In particular, the corner portion on the rubber ring receiving port 3 side at the upper opening of the branch pipe section 7 for the LT joint forms a pipe bottom-down curved surface 8, while the corner portion on the plug receiving port 6 side is Since the orthogonal edges are formed, it is difficult to secure the thickness of the branch pipe portion 7. The curved surface 8 descending along the pipe bottom gradually decreases along the pipe wall with the maximum curvature at the pipe bottom.

Therefore, it is preferable that L is set to about 60 mm when the condition of securing the radius of the curved surface 8 at the bottom of the pipe and enabling the cutting of the tip of the branch pipe after blow molding is satisfied. There was found. In particular, it is preferable that the shape of the LT joint branch pipe portion 7 is formed in the spigot portion 18.

Therefore, an injection-molded or blow-molded PVC color joint 19 is adhesively joined to the spigot 18 of the branch pipe section 7 for LT joint. Therefore, the joint body 2 of the injection molded or blow molded article is bonded and joined to the joint body 2 of the blow molded article as a single piece of the joint main body 2.

Therefore, since the color joint 19 can be changed as described later, it can be diversified from an injection molded joint body.

The collar joint 19 comprises a receiving portion 20 and a spigot portion 21. In particular, the receiving portion 21 is formed into a shape to be joined to the outer surface of the curved surface 8 descending from the bottom of the tube. And
A straight pipe 67 with a receiving port is connected to the color joint 19.

Although the port of the straight pipe 67 is shown as an adhesive port, it may be a rubber ring or a spherical port.

In this color joint 19 as well, if the spigot joint is stopped and a spherical universal joint or a joint with a rubber ring socket is used, the outer sub pipe 32 is adjusted vertically to the inflow pipe 59 having a large gradient. can do.

Next, the operation of the above-described manhole joint 1 will be described. In order to connect the inflow pipe 59 to the manhole body 4 made of concrete, the joint body 2 is inserted into the manhole body 4 in a substantially horizontal shape and fixed by a mortar coking 64.

Then, the inflow pipe 59 is connected to the rubber ring receiving port 3 of the joint body 2, the outer sub pipe 32 is connected to the branch pipe section 7, and the plug 5 is inserted into the plug receiving port 6.

The outer sub-tube 32 is constituted by a sub-tube slide curved tube 33 in addition to the straight tube 67 with a port. The slide curved tube 33 has a rubber ring receiving port 34 at the upper part and a spigot at the lower part. 35
Have. Then, sand is wrapped around the outer auxiliary pipe 32.

That is, unlike the conventional porcelain tube, the outer sub tube 32 can be firmly integrated, so that concrete hardening can be omitted.

Therefore, the wastewater flowing through the inflow pipe 59 is
A virtual 9 formed on the end face of the rectifying insertion portion 11 of the plug 5
The extended outer curved wall 13 of the elbow with a large bend of 0 ° and the curved surface 8 descending from the bottom of the branch pipe portion 7 are rectified, rectified, turned vertically downward, flow smoothly, and accumulate solid matter (filtration). prevent.

In addition, the joint body 2 is short (for example, when the inflow pipe 59 has a diameter of 200 mm), it can be easily attached and detached as if the length of the plug 5 on the pipe axis is 200 mm, and the sealing property is good. 4 is detachably inserted, and the insertion end face is bent from the upper opening end of the branch pipe portion 7 for the LT joint to the inflow pipe 59 side. Since the downstream manhole joint 69 of the pipe 56 is omitted, the external sub pipe 32 can be brought as close as possible to the manhole body 4, and the installation place of the manhole can be reduced, and the parts can be reduced. The construction cost can be reduced and the cost can be reduced.

When cleaning the inflow pipe 59 and the outer sub-pipe 32 with a cleaning tool such as a cleaning rod, if the insertion pipe 59 is inserted from the inflow pipe 59 side without removing the plug 5, the extended outer curved wall 13 is removed.
And the outer sub pipe 32 can be cleaned.

Of course, in a general work for inspecting and cleaning the inflow pipe 59, an operator who gets down in the manhole removes the plug 5 and uses it as a peephole. When the plug 5 is removed, no drainage is received because the drainage does not stay in the manhole joint 1.

Incidentally, in this manhole joint 1, the connection with the inflow pipe 59 is constituted by the rubber ring socket 3, but the present invention is not limited to this, and it may be an adhesive socket or a spigot.

[0059]

According to the present invention, the joint body of the outer pipe member for a manhole, which is extremely simple and relatively large, is manufactured by blow molding by the cold parison method. Diameter 200mmφ, diameter 200 of outer auxiliary pipe
Not only can it be applied to the size of mmφ, but it can easily form the curved surface down the tube bottom while taking advantage of the advantages of blow molding (large or thick, suitable for medium and small volume production). In combination with a low-pressure, inexpensive mold for blow molding, the production cost can be reduced, and the drainage to the external pipe can be smoothly performed.

In particular, since the connecting portion for the branch pipe is formed at the spigot, and the color joint is externally fitted and bonded and joined, it is possible to secure the connection strength in the external sub pipe.

[Brief description of the drawings]

FIG. 1 is an overall vertical sectional view of an embodiment of the present invention.

FIG. 2 is an exploded view of a main part of FIG.

FIG. 3 is a conventional example.

FIG. 4 is a conventional example.

[Explanation of symbols]

1: Manhole joint, 2: Joint body, 3: Rubber ring socket,
4: Manhole body, 5: Plug, 6: Plug socket, 7
... branch pipe, 8 ... curved surface down the pipe bottom, 19 ... color joint

Claims (2)

(57) [Claims] 1. A branch pipe connecting part is downwardly provided between a main pipe connecting part for connecting a horizontal inflow pipe and a plug receptacle for inserting a plug having a concave end face facing the inflow pipe at an insertion end face. An outer joint member for a manhole in which a color joint for connecting an outer sub-tube whose downstream side opens toward the inversion of the manhole is joined to the branch pipe connecting portion with the joint body provided integrally. The joint body is formed by blow molding in which the area is increased by reducing the thickness by the cold parison method using a PVC pipe, and the branch pipe connecting portion is formed by a cold pipe on the inflow pipe side. The end portion is formed of a branch pipe portion for an LT joint which is largely bent downward from the pipe line, and the corner portion of the branch pipe portion for the LT joint on the plug receiving side orthogonal to the edge thereof. in it constitutes, moreover the the branches pipe connecting section, blow - cutting the tip after molding, First, the pipe joint is formed at the spigot portion formed with the curved surface at the bottom of the pipe, and the color joint is formed so as to be joined to the outer surface of the curved surface at the bottom of the pipe, and is adhesively bonded to the spigot portion. An outer sub-tube member for a manhole, wherein the connection strength of the outer sub-tube is ensured by ensuring the thickness. 2. The outer sub-tube member for a manhole according to claim 1, wherein the lower half of the plug is closed and the upper half is provided with a water passage portion in a semi-cylindrical shape.