JPH0714718Y2 - Corrugated pipe fittings - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is used for corrugated pipes used for underdrain drainage pipes, and more specifically for corrugated pipes in which ring-shaped concave grooves are formed at intervals over the entire length of the inner surface. Related to joints.

[Conventional technology]

The corrugated pipe made of a synthetic resin such as polyethylene resin is excellent not only in strength and durability but also in flexibility, and has been conventionally used as a buried underground pipe such as an underdrain drainage pipe. And, when constructing an underdrain drainage pipe over a wide area, a corrugated pipe made of synthetic resin is rolled and mounted on a grooving machine such as a trencher, and a groove for burying the corrugated pipe is excavated and excavated. In some cases, a construction method is adopted in which the corrugated pipe is fed into the groove in parallel.

In the case of such a construction method, the corrugated pipe is sequentially fed out by the feeding roll and continuously fed into the excavated groove, but when passing through the feeding roll, the corrugated pipe is forcibly bent to an angle close to a right angle. Further, after being sent out into the groove, a large tensile force is applied in the longitudinal direction of the corrugated pipe in order to correct the curl when the roll is wound.

On the other hand, since there is a limit to the length of the corrugated pipe that can be wound into a roll and mounted on the grooving machine, the corrugated drain pipe longer than that length must be fed into the groove before Before the end of the pipe passes through the pay-out roll, the leading end of the subsequent corrugated pipe is connected to the end of the corrugated pipe via a tubular joint, thereby extending the corrugated pipe. Adopted.

When the corrugated pipe is extended by this method, if a joint of the type in which the end of the corrugated pipe is internally fitted is used, the end of the joint is formed between the end of the joint and the outer surface of the corrugated pipe. Inevitably, a step protruding from the outer surface is formed, and the step may impair the smoothness of feeding the corrugated pipe by the feeding roll. Therefore, as the joint, a type in which the end of the corrugated pipe is externally fitted is often used.

Conventionally, a joint of the type in which the end of the corrugated pipe is externally fitted has a projection formed on the outer surface of the tubular body on a concave line formed on the inner surface of the corrugated pipe externally fitted to the tubular body. It was configured to engage.

[Problems to be solved by the device]

However, as described above, a large tensile force is applied to the corrugated pipe in the longitudinal direction, and in addition, the tubular body of the joint and the corrugated pipe are often made of a relatively flexible synthetic resin. When a corrugated pipe or joint is used, the joint or corrugated pipe is bent by the tensile force applied to the corrugated pipe to disengage the projections from the recesses, and the corrugated pipe separates from the joint. Occasionally, it happened.

The present invention has been made in view of the above circumstances, and is a type in which a corrugated pipe is fitted outside, and even if it is made of synthetic resin, there is no concern that the corrugated pipe will come off due to the tensile force applied to the connection portion. It is an object to provide a joint for a corrugated pipe.

[Means for Solving the Problems]

The corrugated pipe joint according to the present invention has a spiral groove at one end and a ring-shaped convex portion at the other end that can be fitted into the concave groove of the corrugated pipe. Made of synthetic resin having a crack for reducing the diameter formed at the other end including
And a spiral convex strip that can be screwed into the concave strip at one end and a ring-shaped convex portion that can be fitted into the concave groove of the corrugated pipe at the other end. A second cylindrical body made of synthetic resin having a crack for diameter reduction formed at the other end including the convex portion forming portion, and the convex portion of the first cylindrical body fitted in the concave groove of the corrugated pipe. The first inner ring made of synthetic resin that backs up the other end portion of the first tubular body including the projecting portion forming portion and the convex portion of the second tubular body are fitted in the concave groove of the corrugated pipe. And a second inner ring made of synthetic resin that backs up the other end of the first tubular body including the projecting portion forming portion.

[Action]

In the joint having this configuration, the other end of the first tubular body is reduced in diameter by utilizing the crack, and the other end of the first tubular body thus reduced in diameter is the end of the corrugated pipe. Plugged into. When the other end of the first tubular body is restored to its original state due to its elasticity after being inserted, the convex portion of the first tubular body fits into the ring-shaped concave groove of the corrugated pipe. Further, when the first inner ring is inserted into the other end portion including the protruding portion forming portion of the first cylindrical body to back up the protruding portion forming portion, a large connecting portion between the first cylindrical body and the corrugated pipe is provided. Even if a tensile force is applied, it is possible to prevent a situation in which the convex portion forming portion is bent and the convex portion of the tubular body is separated from the concave groove of the corrugated pipe. The same action is achieved for the second tubular body and the second inner ring.

Since the first tubular body or the second tubular body and the corrugated tube are in the state where the ring-shaped convex strip and the ring-shaped concave groove are engaged with each other, the first tubular body or the second tubular body The barrel can be rotated in place with respect to the corrugated tube. Therefore, the first tubular body and the second tubular body are rotated with respect to the corrugated pipes respectively connected thereto, and the spiral groove of the first tubular body and the spiral convex of the second tubular body are rotated. If the strips are screwed together, the corrugated tubes are connected to each other via the first tubular body and the second tubular body.

〔Example〕

FIG. 1 shows the joint 100 in use according to an embodiment of the present invention.

The joint 100 includes the first tubular body 10, the second tubular body 20, and the first inner ring 30.
And the second inner ring 40.

A spiral recess 11 is formed at one end of the first tubular body 10,
Several ring-shaped protrusions 12 are formed at the other end at predetermined intervals. An ear edge 13 that protrudes inward is formed on the other end edge of the first tubular body 10, whereas the ear edge 13 faces the inner surface of the slightly inner side portion of the convex portion forming portion. The protrusions 14 are formed at a plurality of locations (for example, three locations) in the circumferential direction. In addition, a crack 15 is formed in the other end portion of the first cylindrical body 10 including the above-mentioned convex portion forming portion. This split 15
Is U-shaped as shown in the figure, or U
It may be formed in a letter shape. Furthermore, the number of cracks 15 is 1.
One or two or more may be used, in short, the cracks 15
It suffices that the other end portion of the first cylindrical body 10 can be reduced in diameter by narrowing.

The second tubular body 20 differs from the first tubular body 10 only in that a spiral ridge 21 is formed at one end thereof, and the other configurations are the same as those of the first tubular body 10. This spiral ridge 21 is the first
It can be screwed into the spiral groove 11 of the cylindrical body 10. Incidentally, 22 is a ring-shaped convex portion formed on the other end of the second tubular body 20, 23 is an edge of the second tubular body 20 which is projected inward at the other end, and 24 is a second edge. A protrusion formed on the inner surface of the inner side portion of the convex portion forming portion of the cylindrical body 20 is a fissure 25 formed on the other end portion of the second cylindrical body 20 including the convex portion forming portion.

The outer diameter of the first inner ring 30 is equal to or slightly smaller than the inner diameter of the projecting portion forming portion of the first tubular body 10, and is formed into a tubular shape. When they are inserted in between, the range of movement in the axial direction is regulated by the edge 13 and the protrusion 14.

The second inner ring 40 has the same structure as the first inner ring 30, and the second inner ring 40 also has the second tubular body.
When it is inserted between the edge 23 and the projection 24 of the 20, the range of movement in the axial direction is restricted by the edge 13 and the projection 14.

The first cylindrical body 10, the second cylindrical body 20, and the first inner ring described above
Both 30 and the second inner ring 40 are easily manufactured by molding a synthetic resin such as polyethylene resin using various known molding methods such as blow molding.

On the other hand, the corrugated pipe 200 is a known one having peaks and valleys alternately over the entire length, and the peaks form a ring-shaped recessed groove 201 on the inner surface.

When the first tubular body 10 is connected to the corrugated pipe 200, before the first inner ring 30 is inserted between the edge 13 and the protrusion 14, a crack 15 is formed.
Is narrowed to reduce the outer diameter of the ring-shaped convex portion 12 to be smaller than the diameter of the corrugated tube 200, and the one end portion (protruded portion forming portion) of the first cylindrical body 10 thus contracted is corrugated tube 200. Insert it at the end of. After the insertion, the elasticity of the first cylindrical body 10 itself is used to expand the cracks 15 to expand the diameter of the ring-shaped convex portions 12, and these convex portions 12 are recessed in the corrugated pipe. It is fitted into the groove 201. After this, mark the first inner ring 30 with arrow A
The protrusion 14 is pushed over in the direction of, and the protrusion 14 is overcome while utilizing its elasticity, and the protrusion 14 is inserted between the edge 13 and the protrusion 14. In the first tubular body 10 connected to the corrugated pipe 200 in this manner, the convex forming portion is backed up by the first inner ring 30, so that even if a tensile force is applied to the connecting portion, There is no concern that the cylindrical body 10 will bend and the convex portion 12 will come out of the concave groove 201 of the corrugated pipe 200. Further, in such a connected state, the first cylindrical body 10 can be freely rotated with respect to the corrugated tube 200 while the ring-shaped convex portion 12 is fitted in the ring-shaped concave groove 201.

Since the same procedure can be followed when connecting the second tubular body 20 to the corrugated tube 200, the description of the procedure for connecting the two is omitted.

As described above, the first tubular body 10 and the second tubular body 20 connected to the different corrugated pipes 200, 200 respectively include the recess 11 and the second tubular body 10 of the first tubular body 10.
The ridges 21 of the cylindrical body 20 are connected to each other only by screwing them together. In this case, since the first tubular body 10 and the second tubular body 20 can be freely rotated with respect to the corrugated tubes 200, 200, respectively, the corrugated tubes 200, 200 are rotated when the tubular bodies 10, 20 are connected. Each task can be done quickly and easily because there is no need to do it.

[Effect of device]

As described above, since the joint of the present invention is of a type in which the corrugated pipe is externally fitted, the corrugated pipe can be smoothly fed by the feeding roll of the grooving machine even at its connection portion. Also,
Even if the first and second tubular bodies and the first and second inner rings are made of synthetic resin, the inner ring is used to form the ridge forming portion of the tubular body which is engaged with the concave groove of the corrugated pipe in a fitting manner. Since it is backed up, even if a large tensile force is applied to the connecting portion between the corrugated pipe and the joint, there is no concern that the tubular body will bend and the corrugated pipe will separate.

Furthermore, since the cylindrical body is rotatably connected to the corrugated pipe, the diameter of the corrugated pipe is not limited to the case of connecting the corrugated pipe of small diameter.
Even when connecting a corrugated pipe with a relatively large diameter of 50 to 70 mm, the spiral concave and convex ridges of the first and second cylinders can be easily screwed together, making connection work extremely easy. The effect is that you can do it.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing a use state of a joint according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Joint, 10 ... 1st cylinder, 11 ... Recess, 12 ... Convex part, 15 ...
Cracks, 20 ... second tubular body, 21 ... projections, 22 ... projections, 25 ... cracks, 30 ... first inner ring, 40 ... second inner ring, 200 ... corrugated pipe, 201 ... concave groove.

Claims (1)

[Scope of utility model registration request] 1. A joint for use in a corrugated pipe in which ring-shaped grooves are formed at intervals over the entire length of the inner surface, the spiral groove being provided at one end and corrugated at the other end. A first cylinder made of synthetic resin, which has a ring-shaped convex portion that can be fitted in the concave groove of the pipe, and has a crack for reducing the diameter formed at the other end including the convex portion forming portion. , Having a spiral convex strip that can be screwed into the concave strip at one end, and a ring-shaped convex portion that can be fitted into the concave groove of the corrugated pipe at the other end, and the location where the convex portion is formed A second cylindrical body made of synthetic resin having a crack for reducing the diameter formed at the other end including the ridge and a convex portion of the first cylindrical body fitted in the concave groove of the corrugated pipe. The first inner ring made of synthetic resin that backs up the other end portion including the convex portion forming portion of the first tubular body and the convex portion of the second tubular body are fitted in the concave groove of the corrugated pipe. A second inner ring made of synthetic resin that backs up the other end of the first tubular body including the projecting portion forming portion, and a corrugated pipe joint comprising: