JPH027357Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a joint used for connecting corrugated pipes used as culvert drainage pipes and the like.

[Conventional technology]

As illustrated in FIG. 6, a conventional joint A of this type has protrusions 110 formed at a plurality of locations on the inner surface of a cylindrical body 100 at intervals.

[Problem that the invention attempts to solve]

With such a fitting A, corrugated pipe 2
When connecting 00 and 200, the cylindrical body 10
0, the corrugated pipe 200 is strongly inserted into the cylindrical body 100, and the convex part 110 is made to ride over the crest 210 of the corrugated pipe 200 by using the elasticity of both, thereby engaging the crest 210 with the ridge 110 of the cylindrical body 100 in the withdrawal direction. I was letting it happen. However, the conventional joint A
In this case, if the protruding width of the protrusion 110 is made small so that the corrugated pipe 200 can be inserted with a small force, the corrugated pipe 200 can be inserted after insertion.
There is a problem that the 0 easily slips out, and conversely, if the protrusion width of the protruding strip 110 is increased, there is a problem that insertion becomes impossible or a very large force is required for insertion.

The present invention solves the above-mentioned problems, and aims to provide a joint that makes it easy to insert a corrugated pipe, but makes it difficult for the corrugated pipe to come out after insertion.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention has a cylindrical body made of synthetic resin equipped with a protrusion that engages with the crest of a corrugated pipe, and a notch-like crack is formed from each end to the middle part. , annular recessed grooves are formed at both ends of the cylindrical body, and a pair of clamping rings for tightening the cylindrical body are externally fitted to the cylindrical body, and these clamping rings are arranged at multiple locations in the circumferential direction of the cylindrical body. A spherical surface that slides on the outer surface of the cylindrical body is formed, and an inwardly bent piece that is engaged with the recessed groove when the cylindrical body is tightened with the tightening ring is formed at the front end thereof. The main points are the following points.

[Operation] According to the above means, when a corrugated pipe is inserted, the crack is pushed wide by the corrugated pipe and the diameter of the cylindrical body is expanded. Easy to plug in. Further, after insertion, the tightening ring is moved to the end of the cylindrical body and the cylindrical body is tightened, thereby ensuring that the protrusions of the cylindrical body engage with the peaks of the corrugated pipe. The tightening ring is moved by sliding the spherical surfaces formed at a plurality of locations in the circumferential direction on the outer surface of the cylindrical body, so that the movement is smooth.

〔Example〕

The joint A illustrated in FIG. 1 is a synthetic resin cylinder 1.
A pair of fastening rings 2, 2 externally fitted to the cylindrical body 1
It consists of. The cylinder 1 has a bellows-shaped flexible part 11 in the center.
It has annular recessed grooves 13, 13 at both ends formed in outwardly expanding guide portions 12, 12. Furthermore, the cylindrical body 1 has two cracks 1 formed in the shape of a cut from each end to the middle part.
It has 4,14. In the illustrated example, two cracks 1
4 and 14 are formed at two locations displaced by 180 degrees from each other to minimize the decrease in strength of the cylinder 1. The cracks 14 may be formed at multiple locations in the circumferential direction. Note that, like the cylinder 100 of the conventional joint A described in FIG. 6, the cylinder 1 is provided with protrusions 15 at a plurality of locations on its inner surface at predetermined intervals. next,
The tightening ring 2 has an annular inwardly bent piece 21 at the front end and a spherical surface 22 bulging inward at the rear end, and this spherical surface 22 slides on the outer surface of the cylinder 1. Further, as clearly shown in FIG. 2, the spherical surfaces 22 are formed at a plurality of locations in the circumferential direction of the tightening ring 2 at equal angle intervals.

According to the above-mentioned joint A, as the corrugated pipe is inserted, the crack 14 is pushed open and the diameter of the cylinder increases. Therefore, even if the protruding width of the convex portion 15 is large, the corrugated pipe can be easily inserted.

FIG. 3 shows a state in which the cylindrical body 1 into which the corrugated pipe 200 is inserted is tightened by the tightening ring 2. That is, the tightening ring 2 is moved from the central position of the cylindrical body 1 shown by the imaginary line in the figure to the end of the cylindrical body 1 as shown by the arrow, so that the inner bent piece 21 fits into the recess of the cylindrical body 1. It is engaged with the entry groove 13. Therefore, even if the cylindrical body 1 is subjected to a diameter expanding action due to bending of the corrugated pipe 200 or the like, the tightening ring 22 will not retreat, and the tightening action of the tightening ring 22 will be reliably exerted. In this tightened state of the cylinder 1, the protrusions 15 of the cylinder 1 are engaged with the peaks 210 of the corrugated pipe 100 in the removal direction. Furthermore, when the tightening ring 2 is moved as described above, its spherical surface 22 slides on the outer surface of the cylindrical body 1. Therefore, the frictional resistance during movement becomes extremely small, and even if the cylindrical body 1 is expanded in diameter as described above, its movement is performed smoothly.

FIG. 4 shows an example of a method for manufacturing a joint.
In this method, by cutting both ends of a blow-molded or injection-molded cylindrical molded product B along cutting lines E-I and Rollo,
Flexible part 11, guide parts 12, 12, recessed grooves 13, 1
3 and protrusions 15... and an inwardly bent piece 2.
1 and a pair of fastening rings 2 having a spherical surface 22 are made, and the fastening rings 2, 2 are externally fitted onto the cylindrical body 1. In this case, if a bulge 3 is formed at the cutting location indicated by cutting lines E and R of the molded product B, and a V-shaped groove 31 clearly shown in FIG. 5 is provided in this bulge 3, This V-shaped groove 3
1 can be used as a guide groove during cutting. It goes without saying that the joint A can also be manufactured by a method other than the above. For example, the cylindrical body 1 and the tightening ring 2 may be made separately, and the tightening ring 2 may be externally fitted onto the cylindrical body 1.

[Effect of idea]

As is clear from the above, according to the joint of the present invention, the corrugated pipe can be easily inserted into the cylindrical body even when the protruding width of the protrusion of the cylindrical body is increased to make it difficult for the corrugated pipe to slip out.
Therefore, it is possible to provide a joint in which a corrugated pipe is easy to insert but difficult to pull out. In particular, in the joint of the present invention, when the tightening ring is moved, the spherical surface of the tightening ring slides on the outer surface of the cylindrical body, so the frictional resistance during movement is extremely small, making it easy to insert the corrugated pipe. This has the advantage that the cylindrical body can be easily tightened. Such a joint can be particularly suitably used when constructing an underdrain drainage pipe that requires on-site connection of a corrugated pipe.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view of a joint according to an embodiment of the present invention, Fig. 2 is a partially cutaway side view of a tightening ring, Fig. 3 is a partially cutaway side view showing the joint in use, and Fig. 4 is the above A side view showing a molded product for manufacturing a fitting,
FIG. 5 is an enlarged cross-sectional view of a part of FIG. 4, and FIG. 6 is a side view showing the conventional joint in use. A...Joint, 1...Cylinder, 14...Crack, 1
5... Convex shape, 2... Clamping ring, 22... Spherical surface, 2
00...Corrugate pipe, 210...Yamabe.

Claims (1)

[Scope of utility model registration request] A notch-like crack is formed from each end to the middle part of the synthetic resin cylindrical body having a protrusion that engages with the peak of the corrugated pipe, and
Annular recessed grooves are formed at both ends of the cylindrical body, and a pair of clamping rings for tightening the cylindrical body are externally fitted to the cylindrical body, and these clamping rings are fitted at multiple locations in the circumferential direction of the cylindrical body. A sliding spherical surface is formed on the outer surface of the cylindrical body, and an inwardly bent piece is formed at the front end of the cylindrical body to be engaged with the recessed groove when the cylindrical body is tightened with the tightening ring. A corrugated pipe fitting that is characterized by: