JPH0534559B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a pipe joint for corrugated pipes, and more specifically, a pipe joint for corrugated pipes that is easy to connect, can be securely prevented from coming off, and is inexpensive and free from leakage. Regarding pipe fittings.

(Prior Art) Conventionally, in order to connect the ends of a pair of corrugates so that there is no liquid leakage, for example, the third to
The connection method shown in Figure 4 is adopted.

In the connection method shown in FIG. 3, the end edges of a pair of corrugated pipes 10a and 10b are abutted and joined together, and a packing material 14 is wrapped around the outer circumferential surfaces of both corrugated pipes near the abutting portion 12. Thereafter, the pair of corrugated pipes are connected by wrapping and tightening a metal belt-like band 16 having a concavo-convex shape whose cross-sectional shape follows the shape of the outer peripheral surface of the corrugated pipe around the outside of the wrapped packing material 14.

On the other hand, in the connection method shown in FIG. 4, each recess 18 near the abutting part 12 of the butt-jointed corrugated pipes 10a and 10b is filled with a sealing material 20, and the outer circumferential surface of the abutting part 12 is smoothed. Next, a packing material 14 is wrapped around the smoothed outer circumferential surface near the abutting portion 12, and then a smooth metal band 16 is wrapped and tightened around the outside of the packing material 14, thereby forming a pair of corrugates. Connect the tubes.

(Problems to be Solved by the Invention) According to the above connection method, it is possible to connect a pair of corrugated pipes.

However, the conventional connection method has the disadvantage that liquid passing through the corrugated pipe easily leaks to the outside of the corrugated pipe from the connecting portion of the corrugated pipe.

In particular, when the liquid flows in a full pipe and pressure is applied to the inner wall surface of the corrugated pipe, it is difficult to avoid liquid leakage from the connecting portion.

This is presumed to be because the packing was not sufficiently tightly attached to the outer circumferential surface of the corrugated pipe.

Furthermore, in the conventional connection method, since the outer circumferential surface of the corrugated pipe has an uneven shape, the connection members used also have a complicated structure, and the connection operation requires a great deal of time and effort.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a pipe joint for corrugated pipes that can reliably prevent leakage of liquid flowing through the pipes and prevent the connected corrugated pipes from coming off, and is quick and easy to construct.

(Means for Solving the Problems) As a result of intensive studies to achieve the above object, the inventor of the present invention has determined that a packing wrapped around the outer periphery of a connecting portion of a pair of corrugated pipes is formed on the outer periphery of the corrugated pipes. It has been discovered that by intermittently pressing the bottom of the valley where the corrugated pipe is located, it is possible to reliably prevent the corrugated pipe from coming off and to stop water, and the present invention has been achieved.

That is, the present invention provides a packing made of an elastic body that covers the outer periphery including the connecting portion of a pair of corrugated pipes;
In a pipe joint comprising a cover plate that covers the seal and a tightening portion that tightens the cover plate,
The covering plate has depressed portions that are depressed from the outer wall surface side of the covering plate to the inner wall surface side and extend in the circumferential direction along the trough portions of the corrugated pipes, at each of a plurality of locations corresponding to the valley portions of the corrugated pipes to be connected. is formed, and the depressed portion pushes out the packing toward the bottom of the valley with its protruding end face relative to the valley, and pinches the packing between the valley wall and the protruding edge facing the valley wall. It is formed in a trapezoidal cross-section such that the angle formed by the wall surfaces of the valley portion and both wall surfaces of the recessed portion facing the valley portion is smaller than the angle formed by both wall surfaces of the valley portion, and the protruding end surface is narrower so as to press and seal. This is a pipe joint for corrugated pipes that is characterized by the following.

(Function) According to the present invention, the troughs of the corrugated pipe and the depressions formed intermittently in the covering plate in correspondence with the troughs are engaged with each other by the tightening force generated by the tightening portion. In addition to preventing the corrugated pipe from coming out, it is also possible to reliably shut off water at the connecting portion of the corrugated pipe.

In other words, the tightening force for tightening the covering plate is concentrated on the protruding end of the depression that extends circumferentially along the valley of the corrugated pipe and has a trapezoidal cross section.

The protruding end on which such tightening force is concentrated penetrates into the vicinity of the bottom of the valley of the corrugated pipe, and the protruding end edge comes into contact with packings on both wall surfaces of the valley.

By the way, since the angle formed by both wall surfaces of the depressed portion is smaller than the angle formed by both wall surfaces of the trough, and the protruding end surface is formed narrower, the packing on both wall surfaces of the trough is formed at the bottom of the trough. direction by the protruding edge.

For this reason, the packing at the bottom of the valley, which has become thick due to the packing extruded from both walls of the valley, is tightly pressed between the bottom and the bottom of the valley by the protruding end surface of the depression against the bottom of the valley. (sealed).

Furthermore, the packing at the top of the ridge of the corrugated pipe sandwiched between the depressions is caused by a combination of the pressing force of the cover plate and the pushing force (tensile force) of the packing toward the bottom of the valley, It is pressed between the outer circumferential surface of the corrugated pipe and is brought into even stronger contact.

Since such parts where the bottom of the corrugated pipe and the top of the ridge are in strong contact with the packing are formed intermittently on the outer peripheral surface of the corrugated pipe, liquid leaking from the connection part of the corrugated pipe can be absorbed in multiple stages. This makes it possible to prevent leakage to the outside of the pipe joint.

(Example) The present invention will be explained in more detail using the drawings.

FIG. 1a is a partially sectional side view showing an embodiment of the present invention, showing a state in which the ends of spiral pipes 22, 22, which are a type of corrugated pipe, are connected by a pipe joint 20.

In this embodiment, the spiral tubes 22, 22
A packing 24 made of an elastic material such as rubber is wrapped so as to straddle the upper surface of the packing plate 32.
is tightened and wound around two bands 36, 36.

The spiral pipe 2 to be connected is attached to the cover plate 32.
The spiral tube 22 is depressed from the outer wall surface side of the cover plate 32 to the inner wall surface side at each of a plurality of locations corresponding to the trough portions 22a formed on the outer peripheral portions of the covering plates 32 and 22.
A depressed portion 28 extending in the circumferential direction along the valley portion 22a of
is formed.

This depressed portion 28 has an angle formed by both wall surfaces of the depressed portion 28 opposite to both wall surfaces of the valley portion 22a as shown in FIG.
As shown in FIG.
It is formed into a trapezoidal cross-section, which is smaller than the angle formed by both wall surfaces of a and whose width is narrower on the protruding end surface side.

Covering plate 32 having such a recessed part 28
A joint 30 is formed in which the cover plate 32 can be opened in the outer circumferential direction of the spiral tubes 22, 22.

As shown in FIG. 1b, this seam 30 has tapered surfaces 30A and 30B superimposed on the lower surface of one end edge 30a and the upper surface of the other end edge 30b of the covering plate 32, so that it is difficult to apply the seam 30. Board 32
It is possible to avoid the wall from being thicker than other parts.

In the pipe joint 20 of this embodiment, when the cover plate 32 is tightened by the bands 36, 36, the tightening force due to the bands 36, 36 is applied to the depressions that are intermittently formed in the cover plate 32. concentrated at the protruding end of section 28.

At such a protruding end, the wall surface (hereinafter referred to as
The protruding edge facing the slope (sometimes referred to as an inclined surface) comes into contact with a packing 24 made of an elastic body near the bottom of the trough 22a.

As described above, this depressed portion 28 is formed by the valley portion 22a.
Since the angle formed by both wall surfaces of the recessed portion 28 facing both sloped surfaces of the trough portion 22a is smaller than the angle formed by both sloped surfaces of the valley portion 22a, and the protruding end surface side is formed to have a narrower trapezoidal cross section, the packing 24 is pushed out toward the bottom of the trough 22a while pressing it against the inclined surface of the trough 22a.

The packing at the bottom of the trough 22a, which has been pushed out from both inclined surfaces of the trough 22a in this manner and has become thicker, is pressed against the bottom of the trough 22a by the protruding end surface, and is pinched between the bottom and the trough 22a. It can adhere strongly.

By the way, although there may be a cavity between the packing 24 wrapped around the circumferential surface of the corrugated pipe 22 and the bottom of the trough 22a, according to the pipe joint of this embodiment, both inclined surfaces of the trough 22a The upper packing can be pushed out and brought into close contact with the bottom of the valley portion 22a.

Here, if the shape of the depressed portion 28 is a trapezoidal or conical cross section in which the protruding end surface side is wider, it is difficult to push out the packing on both inclined surfaces of the trough 22a to the bottom of the trough 22a. becomes.

In addition, when the shape of the depressed portion 28 is a square cross section, the protruding end surface cannot enter the vicinity of the bottom of the valley 22a, and the pressing force for pressing the packing at the bottom of the valley 22a becomes small. The packing cannot be pressed sufficiently against the bottom.

In this embodiment, the packing 24 is in close contact with the top of the ridge 22b of the spiral tube 22 due to the pressure caused by the tightening force of the bands 36, 36, and the tip of the recessed portion 28 Due to the tensile force on the packing 24 due to
is more tightly adhered to the top of the mountain portion 22b.

In this embodiment shown in FIG. 1a,
Since such depressions 28 are formed at multiple locations on the cover plate 32, the spiral tube 2 with a complicated shape
Portions where the outer circumferential surfaces of the spiral tubes 2, 22 and the packing 24 are in close contact can be formed intermittently on the outer circumferential surface of the spiral tube 22, and the spiral tubes 22, 22 can be reliably prevented from slipping out.

Furthermore, liquid leaking from the connecting portion of the spiral pipes 22, 22 can be stopped in multiple stages, and water leakage from the pipe joint 20 can be reliably prevented.

In the pipe joint 20 shown in FIG. 1a, a band 3 is used as a tightening means for tightening the cover plate 32.
6,36 is used, but as shown in Figure 2,
Flanges 38, 38 formed at both ends of the cover plate 32 may also be used.

The cover plate 32 can be tightened by sandwiching the packing 40 between the flanges 38, 38 and tightening the flanges 38, 38 with bolts 42 and nuts 44.

In the embodiments described above, a pipe joint used for a spiral pipe has been described, but it goes without saying that the pipe joint of the present invention can also be used for other corrugated pipes.

(Effects of the Invention) According to the pipe joint of the present invention, water leakage can be prevented even when pressure is applied to the inner wall surface by flowing liquid in a full pipe.

Furthermore, even large-diameter corrugated pipes can be easily connected, and the connection work can be performed quickly.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view showing one embodiment of the present invention, and FIG. 2 is a side view showing another embodiment. In the figure, 20...pipe joint, 22...spiral pipe, 22a...trough, 22b...peak, 28
... recessed part, 24 ... packing, 32 ... cover plate, 36 ... band, 38 ... flange, 42
...Bolt, 44...Natsuto.

Claims (1)

[Scope of Claims] 1. A pipe joint comprising a packing made of an elastic body that covers an outer circumference including a connecting portion of a pair of corrugated pipes, a covering plate that covers the packing, and a tightening portion that tightens the covering plate, The covering plate has depressed portions that are depressed from the outer wall surface side of the covering plate to the inner wall surface side and extend in the circumferential direction along the trough portions of the corrugated pipes, at each of a plurality of locations corresponding to the valley portions of the corrugated pipes to be connected. is formed, and the depressed portion pushes out the packing toward the bottom of the valley by the end surface protruding from the valley, and pushes the packing between the valley wall and the protruding edge facing the valley wall. The groove is formed into a trapezoidal cross-sectional shape in which the angle formed by the wall surface of the trough and both wall surfaces of the recessed portion facing the trough portion is smaller than the angle formed by both wall surfaces of the trough portion, and the protruding end surface side is narrower so as to be compressed and sealed. Pipe fittings for corrugated pipes.