JPH01210685A - Joint structure of spiral tube - Google Patents

Abstract

PURPOSE:To accurately connect spiral tubes into mutually jointed state by forming the opposite ends of spiral tubes to be connected with a hollow spiral stripe part cut off half on its periphery respectively, and abutting their opposite ends each other with a packing fittedly fixed between them. CONSTITUTION:Both ends of spiral tubes 1, 2 are severally formed with a spiral opening part 5 which is shaped by spirally cutting the central part of a hollow spiral stripe part 3 by one turn to remove its half and to leave the other half having a fixed axial depth. The opposite opening parts are mutually abutted to make inside and outside end faces 7, 8 and bottom end faces 6 fit mutually on their whole contact surfaces to form a hollow spiral part 3a. Thus the hollow spiral stripe parts 3 of both the spiral tubes 1, 2 are serially connected. A packing 9 is fixedly fitted into the hollow spiral stripe part 3a formed by joining the openings 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a joint structure for a spirally wound pipe whose pipe wall is formed by a continuous hollow spiral strip.

[Prior Art] Conventionally, when connecting pipes to each other, in order to provide a watertight seal between the opposing ends, a sleeve is fitted between the outer peripheral surfaces of the opposing ends of the pipes, and the inner periphery of the sleeve is It is widely used to interpose an annular seal between the surface and the outer peripheral surface of the tube.

[Problems to be Solved by the Invention] However, with such a joint structure, the diameter of the joint increases due to the fitting of the sleeve, which not only causes problems in construction, but also causes problems in spirally wound pipes, especially Even if an annular sealing material is applied to a spirally wound pipe whose pipe wall is formed by spirally wound protrusions, the gap between the inner circumferential surface of the sealing material and the circumferential groove between the helical protrusions is A space is created between the seals and the sealing effect cannot be achieved.

Therefore, in order to perform such a joint between spirally wound pipes, the spiral circumferential grooves at the opposite ends of both spirally wound pipes are filled with putty or the like to form the outer circumferential surfaces of the ends into flat surfaces, and then the outer circumferential surfaces of the ends are made flat. By fitting a split sleeve between the flat outer peripheral surfaces of the ends of both spirally wound tubes, and tightening with bolts and nuts, etc., with a sealing material interposed between the flanges protruding from the opposing edges of these half sleeves. However, in the case of large-diameter spiral-wound pipes, it is difficult to use such a joint structure from the viewpoint of workability, and as above, the diameter of the joint increases. There were some problems during construction.

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and provide a joint structure for spirally wound pipes that can accurately connect spirally wound pipes of a desired length in a continuous manner.

[Means for Solving the Problems] In order to achieve the above object, the joint structure for spirally wound pipes of the present invention includes half hollow spiral stripes in the circumferential direction at opposite ends of the spirally wound pipes to be connected. An opening is formed in a spiral shape to expose the hollow interior, and the packing is spirally fitted into the hollow spiral strip formed by bringing the open ends of these openings into contact with each other. It is characterized by:

[Function] The hollow spiral strip that forms the tube wall at the open end has half of it spirally cut out in the circumferential direction to form an opening that exposes the hollow interior, so it can be connected to d. When the opposite end surfaces of the spirally wound tubes to be used are joined together, these openings form a hollow spiral section having the same shape as the tube walls of both spirally wound tubes.

When connecting these two spirally wound tubes, if a rod-shaped packing having a shape that fills the hollow inside of the hollow spiral stripe is fitted into the spiral opening of one of the spirally wound tubes, the thickness direction of the packing is One half of the tube is fitted over its entire length into the opening of the spirally wound tube, and the other half protrudes from the opening. When the helical opening of the other spirally wound tube is fitted into this protruding part, both spirally wound tubes are connected through the packing, and the part where the packing is installed is connected to the opening of both spirally wound tubes as described above. Form a spiral striation with the same shape as the wall.

Both spirally wound tubes connected in this manner are closed at their circumferential joint end faces from the inside by packings to prevent water from entering. Further, the joint end surfaces in the longitudinal direction may be sealed by applying an appropriate adhesive or filler.

〔Example〕

Embodiments of the present invention will be explained with reference to the drawings: (1) (2)
) is a synthetic resin spirally wound tube to be connected, which is obtained by cutting a relatively large diameter long spirally wound tube to a desired length.

The spirally wound tube has a tube wall formed by a hollow spiral strip (3), and the spirally wound tube (1) (2) shown in FIG.
In this case, the spiral ridges (3) form continuous spirally wound protrusions with a constant pitch, and the troughs (4) have spiral grooves between the pitches. The inner circumferential surface of the trough (4) and the inner circumferential surface of the spiral strip (3) are flush and continuous to form an inner circumferential pipe wall surface having the same diameter over the entire length. It is.

In order to obtain such a spirally wound tube, for example, a half-molten synthetic resin strip is first wound around several molding rotating shafts arranged on a virtual cylinder, and the end edge of the previously wound strip is wound. It is formed by continuously winding the strip material in a spiral shape so that the opposite end edges of the next wound strip material overlap, and the hollow spiral strip portion (3)
can also be obtained by forming protrusions in the longitudinal direction of the synthetic resin strip material, but it is also possible to form them on the molding rotating shaft.

When the long spirally wound tube manufactured in this way is cut into a circular shape in the diametrical direction, the hollow spiral striations (3) and the troughs (
4) is inclined with respect to the tube axis, so it is cut from these spiral striations (3) to the troughs (4).
The end face of the thick part of the pipe wall and the open end face of the hollow part of the spiral strip (3) whose depth gradually changes appear on the vertical plane. Therefore, after manufacturing a large number of spirally wound pipes of the desired length, Even if the end surfaces of arbitrary spirally wound tubes are joined together, the end surfaces will not match perfectly like circular tubes with constant wall thickness, and misalignment will occur.

For this purpose, at both ends of the spirally wound tubes (1) and (2) described above, the central part of the hollow spiral strip (3) is spirally cut by - turns (- turns) and half of it is removed. , the remaining half portion forms a spiral opening (5) with a constant depth.

The cutting start end and the cutting end in the circumferential direction of this spiral opening (5) are in contact with each other by one pitch, and between these ends, the hollow spiral parts that are cut in the length direction of the tube and are adjacent in the front and back are opposite to each other. The end face (6) of the side wall and the cross section of the valley (4) are continuously exposed on a vertical plane. (7) and (8) are cut end surfaces of the inner and outer walls of the spiral opening (5).

Spiral-wound tubes (1) (2) forming both open ends in this way
), if the opposing openings are brought into contact with each other, the spiral openings (5) (5) of both spirally wound tubes (1) (2)
The inner and outer end surfaces (7) and (8) of the hollow spiral striation (
A hollow spiral strip (3a) is formed by the matching of both openings (5) (5) in the shape of halving 3), and both spirally wound tubes (1
) The hollow spiral stripes (3) in (2) are continuous.

(9) is a packing made of an elastic material such as rubber or soft synthetic resin that is fitted into the hollow spiral strip (3a) formed by joining the openings (5) and (5). They are formed in the same cross-sectional shape and have a length that can completely fill the hollow spiral strip (3a), that is, the spiral shape is -
It is formed into a rod shape or an end ring shape with a length that can be rolled to seal the joint end surfaces of the openings (5) (5) over the entire length.

Note that this packing (9) is formed to be longer than the circumference of the hollow spiral strip (3a), and its both ends are connected to both spirally wound tubes (2).
(3) The connection strength can also be increased by fitting it into the hollow spiral strip (3) (3).

In order to connect the two spirally wound tubes (1) and (2) by fitting such a packing (9) into the hollow spiral strip (3a), first, the spiral shape of one of the spirally wound tubes (1) is After fitting one half of the packing (9) in the thickness direction into the opening (5) over the entire length, the other spiral winding is applied to the other half of the packing (9) protruding from the opening (5). It is sufficient to fit the spiral opening (5) of the tube (2).

After connecting the spirally wound tubes (2) and (3) in this way, the joint end surfaces in the longitudinal direction, that is, the joint end surfaces of the valleys (6), are sealed and closed by applying an appropriate adhesive or sealant. let

In addition, if necessary, the joint end surface in the circumferential direction, that is, the opening (5
), the two spirally wound tubes (102) can be firmly connected by integrally connecting the inner and outer end surfaces of the tubes (102) with adhesive.

To make this connection stronger, for example, a short helical tube made of hard synthetic resin or metal with the same shape as that of the spirally wound tube (Fig. (not shown), and as described above, both spirally wound tubes (1) (
After connecting 2), rotate this short spiral tube while sliding it on the outer circumferential surface of the spirally wound tube (1) so that its half part is fitted onto the outer circumferential surface of the other spirally wound tube (2). good. Further, a member that fits into these circumferential grooves is continuously wound in a continuous spiral between the helical circumferential grooves at the ends of both spirally wound tubes (1) and (2), and the member is integrally adhered to the circumferential groove. It can also be connected by

Next, FIGS. 4 and 5 show another embodiment of the present invention. In the above embodiment, a protruding ridge protruding from the trough (4) is formed by a hollow spiral ridge (3). However, in this embodiment, the spirally wound tube (1) is made such that the opposing side walls of the hollow spiral strip (3) having a rectangular cross section are brought into close contact with each other without forming a valley, so that the inner and outer circumferential surfaces are smooth. (2).

The same joint structure as in the above embodiment is also used to connect the spirally wound tubes (1) and (2).

That is, at both ends of the spirally wound tubes (1) and (2), the central part of the hollow spiral strip (3) is spirally cut by - turns (- turns), half of it is removed, and the remaining part is cut. The halves form a spiral opening (5) of constant depth.

The cutting start end and cutting end in the circumferential direction of this spiral opening (5) are shifted by one pitch, and the space between the ends is cut in the length direction of the tube to form a joint end surface (6). . (Force (8) is the cut end surface of the inner and outer walls of the helical opening (5).

These spirally wound tubes (1) and (2) are combined into a hollow spiral tube section (3).
When connected through a gasket (9) having the same cross-sectional shape as the one formed in the inner and outer end surfaces (7) and (8) of the spiral openings (5) and (5) of both spirally wound tubes (102) and in the length direction. The joint end surfaces (6) completely match each other to form a hollow spiral strip (3).
A hollow spiral strip (3a) is formed by the matching of both openings (5) (5), which are cut in half.
The hollow spiral stripes (3) of (2) are continuous.

The other structures and the connection method via the packing (9) are the same as in the previous embodiment.

It should be noted that the spiral openings (5) of the spirally wound tubes (1) and (2) are not formed so as to form one complete turn, but are formed close to one turn as shown in Fig. 6. The spirally wound tubes (1) and (2) can be reliably joined via the packing (9) by forming a straight cut end surface (6a) between both ends inclined in the length direction of the tube. It is.

Further, the spirally wound tube (IO2) is not limited to a synthetic resin tube, but the present invention can be applied to a hollow spirally wound tube made of metal.

[Effects of the Invention] As described above, according to the joint structure for spirally wound pipes of the present invention, the opposite ends of the spirally wound pipes to be connected are provided with a hollow spiral strip in half and a notch in a spiral shape in the circumferential direction. The sleeve-based joint method is used because an opening is formed to expose the hollow interior, and a packing is fitted into the hollow spiral striation formed by bringing these opening ends into contact with each other. It is possible to reliably connect spiral-wound tubes that cannot be used together, and in addition, the hollow spiral strip that forms the tube wall at the open end is hollow by cutting out half of it in a spiral shape in the circumferential direction. Since the openings are formed to expose the inside, when the opposite end surfaces of the spirally wound tubes to be connected to each other are joined, these openings form a hollow spiral strip of the same shape as the pipe walls of both spirally wound tubes. Therefore, it has the appearance of a series of spirally wound tubes, and the inner circumferential surface is continuous on the same surface without any adverse effect on fluid fluidity or piping work.

Furthermore, since the gasket is continuously fitted and installed between the openings of both spirally wound tubes, it is possible to completely seal the joint end surface with the gasket and reliably prevent water from entering. It is possible.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; Fig. 1 is an exploded perspective view showing the joint structure of Example 1, Fig. 2 is a side view of both spirally wound pipes connected, and Fig. 3 is a cross section of the joint part. Figure 4 is example 2
5 is a sectional view of the joint portion thereof, and FIG. 6 is a side view showing still another embodiment of the present invention. (1) (2)...Spiral-wound tube, (3)...Hollow spiral strip, (4)...Trough, (5)...Spiral opening, (
6)(7)(8)...Cut end surface. -Song 4B Figure 5Figure 5- Go to F11-

Claims (3)

[Claims] (1) At the opposing ends of the spirally wound pipes to be connected, an opening is formed by cutting out half of the hollow spiral section in a spiral shape in the circumferential direction to expose the hollow interior, and these open ends A joint structure for a spirally wound pipe, in which a packing is fitted in a spiral shape into a hollow spiral section formed by bringing the two into contact with each other. (2) The spirally wound tube according to claim (1), wherein the hollow spiral strip is wound spirally at a constant pitch to form a tube wall of the spirally wound tube. Joint structure. (3) A joint structure for a spirally wound pipe, characterized in that the hollow spiral strip is tightly wound to form a pipe wall of the spirally wound pipe.