WO2006120329A1

WO2006120329A1 - Flexible tubular element

Info

Publication number: WO2006120329A1
Application number: PCT/FR2006/001015
Authority: WO
Inventors: Jean-Michel Paucod; Jean-Pierre Serin
Original assignee: Raccords Et Plastiques Nicoll
Priority date: 2005-05-13
Filing date: 2006-05-05
Publication date: 2006-11-16
Also published as: FR2885673A1; FR2885673B1

Abstract

A flexible tubular element (1) comprising a fluted outer wall (6) and a set of coils (S) sealed together and each deformable between a stretched position and a contracted position, wherein each of said coils is made from a profile portion (2) with a three-sided cross-section (11, 12, 13) substantially defining an open triangle, and a first side (11) of said profile portion and a second side (12) of said profile portion can form a fluting channel in the outer wall while a third side (13) of said profile portion can form an internal portion associated with said coil and forming part of the inner wall (30) of said tubular element in such a way that the inner wall of the tubular element is substantially cylindrical.

Description

FLEXIBLE TUBULAR ELEMENT

The present invention relates to a flexible tubular element having a fluted outer surface. In the field of building, several trades implement pipelines and connections using flexible tabular elements to quickly and easily make elbows at any angles not remarkable, or combinations of non-coplanar angles he is hard to get with rigid elements. Two categories of flexible tabular elements are generally used. The first category groups flexible non-self-supporting tabular elements. These tabular elements have a facility of obvious shaping, but do not keep the form which is given to them because, not self-supporting, they sag between their points of connection under their own weight and under the weight of the effluents, in creating counter-slopes in which the effluents stagnate. In addition, these tabular elements generally have inside a fluted surface identical to the outer surface, significantly penalizing the efficiency of the section hydraulically, and creating obstacles to which the effluents cling, which prevents self-cleaning necessary, especially in the case of a sanitary application.

It is for example known from EP 474 449 a corrugated wall tube made flexible by thinning the base portions of the corrugations, that is to say the smaller diameter portions. The corrugations of the wall of this tube can thus be stretched or contracted elastically depending on the path along which the tube is installed. Each corrugation is for example made of a profile having four sides generally forming a triangle completed by a connecting arm.

The second category groups self-supporting tabular elements. In these tabular elements, the walls of the grooves are deformed until elastically reach two stable positions, one stretched, the other contracted, and, thus locking, give the tabular element a stable general shape. Contracting or to stretch the turns selectively along the tubular element allows to obtain radii of curvature which result from the sum of the elementary angles provided by each turn. The stiffness of these products makes it possible to avoid sagging between the connection points, which avoids counter-slopes, but the retention of effluents can always occur in the hollow of the turns of the internal face, which makes it detrimental. the use of these products for sanitary applications.

EP 0 185 934 discloses a flexible tubular element made from a metal strip provided with a longitudinal groove. The metal strip is wound helically, so that the outer wall of the tubular element has grooves and that its inner wall is substantially cylindrical. However, it is particularly difficult to obtain a good seal from a metal winding, which complicates the realization of such a tubular element.

The present invention aims to provide a flexible tubular element avoiding at least some of the aforementioned drawbacks. The present invention also aims to provide a method of forming such a tubular element.

To this end, the subject of the invention is a flexible tubular element comprising a corrugated outer wall, said tubular element comprising a set of turns fixed in a sealed manner to each other, each turn being deformable between a stretched position and a contracted position, characterized in that each of said turns is formed from a profile whose section comprises three sides, constituting substantially an open triangle, a first side of said profile and a second side of said profile being able to constitute a groove of said outer wall and a third side of said section being adapted to form an inner portion, associated with said turn, of the inner wall of said tubular member so that the inner wall of the tubular member is substantially cylindrical.

Advantageously, said first side is thicker than said second side.

According to a characteristic of the invention, an edge of said third side is free and extends beyond said second side, so that the inner portion associated with said turn is able to partially cover the inner portion associated with an adjacent turn, including in a stretched position. Preferably, said inner portion associated with said turn is slidable along said inner portion associated with the turn adjacent said turn when said turn is deformed between its contracted position and its stretched position.

According to one embodiment of the invention, said tubular element is made of thermoplastic material.

The invention also relates to a method of forming a flexible tubular element, characterized in that it comprises the steps of:

forming at the extruder outlet a profile whose section comprises a first side, a first edge of said first side carrying a second side, a second edge of said first side, opposite said first edge, carrying a third side, said first, second and third sides substantially constituting an open triangle, said first side being thicker than said second side and said third side, the free edge of said third side extending beyond the free edge of said second side, - winding said profile on a mandrel to form a first turn, said third side of said profile being disposed against the surface of said mandrel, said first and second sides constituting a groove,

winding said profile on said mandrel so as to form a second turn, said free edge of the second side of said second turn being disposed along said second edge of the first side of said first turn, and simultaneously soldering said free edge of the second side said second turn with said second edge of the first side of said first turn.

The invention will be better understood, and other objects, details, features and advantages thereof will appear more clearly in the following detailed explanatory description of an embodiment of the invention given as a purely illustrative and non-limiting example, with reference to the accompanying schematic drawings.

In these drawings: FIG. 1 is a partial view from above of a tubular element according to one embodiment of the invention; Figure 2 is a cross-sectional view of the profile used to form the tubular member of Figure 1; Figure 3 is a partial longitudinal sectional view taken along the line III-III of Figure 1, showing turns of the tubular member in the stretched position; and FIG. 4 is a view similar to FIG. 3, showing turns of the tubular element in the contracted position.

Referring to Figure 1, there is shown a tubular element 1 having a set of turns S forming grooves defining an outer wall 6 of the tubular element 1. The turns S are fixed to each other, as will be described in detail later, so as to form a helical winding.

Each turn S is deformable between a contracted position and a stretched position, which define two stable positions. Thus, when a user deforms a turn S until it reaches its stretched position (respectively contracted) the turn S locks elastically in the stretched position (respectively contracted). By acting again on the turn S, the user can similarly deform the turn S until it resumes its contracted position (respectively stretched). In FIG. 1, the turn S ₁₁ is in the contracted position and the turn S ₁₀ is in the stretched position.

Figure 1 also shows a turn S ₁₇ , a first portion 4 is placed in the stretched position, and a second portion 5, substantially diametrically opposed to the first portion 4, is placed in the contracted position. The turn S ₁₇ then forms an angle α. In the same way, several adjacent turns are deformed to form elementary angles α. Note that the different elementary angles are not necessarily in the same plane. The set of adjacent turns forming elementary angles α constitutes a bend 3 of the tubular element 1, the total angle of the bend 3 being equal to the sum of the elementary angles of the different turns.

We will now describe a device (not shown) and a method for obtaining the tubular element 1. The device comprises an extruder (not shown) provided with a mouth giving the profile of a section 2 of plastic. The profile 2 has a section formed by three sides, a first side 11, a second side 12 and a third side 13, which substantially constitute an open triangle, as shown in FIG. 2. An edge 1a of the first side 11 carries an edge 12a of the second side 12. The second edge 12b of the second side 12 is free. An edge 1 Ib of the first side 11 carries an edge 13a of the third side 13. The second edge 13b of the third side 13 is free. The first side 11 is thicker than the second side 12 and the third side 13, so that the section 2 has sufficient overall rigidity. The free edge 13b of the third side 13 extends beyond the free edge 12b of the second side 12. When the profile 2 leaves the die of the extruder, it is wound on a mandrel (not shown), so that the outer face of the third side 13 of the profile 2 is in contact on its entire surface with the mandrel. When the mandrel has made a turn, that is to say 360 °, a first turn S ₁ (Figure 3) is formed. At this time, the die of the extruder is arranged relative to the mandrel so that the second side 12 of the profile leaving the die is at the first side 11 of the turn S ₁ formed in the previous turn of the mandrel. When the mandrel continues to rotate, a second turn S ₂ begins to form, the edge 12b of the second side 12 of the turn S ₂ being positioned on the mandrel against the edge 1 Ib of the first side 11 of the turn S ₁ . Simultaneously, the edge 12b of the turn S ₂ is welded to the edge 11b of the turn S ₁ with the aid of a welding means (not shown) disposed near the extruder. The welding is carried out continuously, the temperature being chosen, in particular as a function of the speed of the mandrel, to ensure an effective weld between the edge 12b of the turn S ₂ and the edge 1 Ib of the turn S ₁ and to avoid deformation of the profile due to excessive heat. In particular, the edge 13b of the turn S ₂ must not be welded against the edge 1 Ib of the turn S ₁ . Thus, the turns S ₁ and S ₂ are sealed together along a junction edge 17.

In the same way, when the mandrel has made two turns and continues to rotate, a third turn S ₃ begins to form, the edge 12b of the turn S ₃ is positioned on the mandrel against the edge 11b of the turn S ₂ , the two edges 12b and 1b being welded simultaneously to each other. The device and the method such as described above thus make it possible to obtain in a very simple manner a tubular element 1 of the desired length.

Figure 3 shows four turns S ₁ , S ₂ , S ₃ and S ₄ of the tubular element 1 obtained by the method described above, the turns being in the stretched position. The tubular element 1 being cylindrical, it is obvious that its longitudinal section has an upper wall and a lower wall, although, to simplify the figures, only the upper wall has been shown in Figures 3 and 4.

In FIG. 3, the edge 13b of the turn S ₄ partially covers the third side 13 of the turn S ₃ . Similarly, the edge 13b of each turn partially overlaps the third side 13 of the previous turn. By convention, the preceding turn is called the preceding turn and has been previously formed. When the tubular element 1 contains a fluid whose direction of flow is symbolized by the arrow 20, the free edge 13b of each turn is pressed against the third side 13 of the previous turn. For example, the free edge 13b of the turn S ₄ is pressed against the third side 13 of the turn S ₃ . The inner surface 30 of the tubular element 1 is then substantially cylindrical, the third side 13 of each turn constituting a portion of the inner wall 30 of the tubular element 1, the different portions being interconnected by thin rims. directed relative to the direction of flow so as not to constitute a cavity or obstacle that can impede the flow.

Starting from the stretched position, when a user compresses the turns against each other, the second side 12 being thinner than the first side 11, it deforms preferentially and locks by elasticity in the contracted position.

Simultaneously, the third side 13 of each turn slides along the third side 13 of the previous turn. The turns are then in their contracted position, as shown in FIG. 4. In this position, when the tubular element 1 contains a fluid whose direction of flow is symbolized by the arrow 21, the edge 13b each turn is pressed against the third side 13 of the previous turn. The inner surface 30 of the tubular element 1 thus has no cavity or obstacle that may hinder the free flow of fluid within the tubular element. On the contrary, the inner surface 30 of the tubular element 1 is substantially cylindrical, which allows the fluid to flow without turbulence and without accumulating in the grooves, the interior of the tubular element thus remaining clean.

Although the invention has been described in connection with a particular embodiment, it is obvious that it is not limited thereto and that it comprises all the technical equivalents of the means described and their combinations if they are within the scope of the invention.

Claims

A flexible tabular element (1) comprising a fluted outer wall (6), said tubular element comprising a set of turns (S) fixed in a sealed manner to each other, each turn being deformable between a stretched position and a contracted position, characterized in that each of said turns is formed from a profile (2) whose section comprises three sides (11, 12, 13), substantially constituting an open triangle, a first side (11) of said profile and a second side (12) of said profile being able to constitute a groove of said outer wall and a third side (13) of said profile being adapted to constitute an inner portion, associated with said turn, of the inner wall (30) of said tabular element so that the inner wall of the tabular element is substantially cylindrical.

2. Tabular element according to claim 1, characterized in that said first side (11) is thicker than said second side (12).

Tabular element according to claim 1, characterized in that an edge (13b) of said third side (13) is free and extends beyond said second side (12), so that the internal portion associated with said turn is able to partially cover the inner portion associated with an adjacent turn, including in the stretched position.

4. Tabular element according to claim 1, characterized in that said inner portion associated with said turn is slidable along said inner portion associated with the coil adjacent to said turn when said coil deforms between its contracted position and its position. stretched.

5. Tabular element according to claim 1, characterized in that it consists of thermoplastic material.

6. A method of forming a flexible tabular element, characterized in that it comprises the steps of:

forming at the extruder outlet a profile (2) whose section comprises a first side (11), a first edge (11a) of said first side (11) carrying a second side (12), a second edge (1 Ib ) of said first side, opposite to said first edge (11a), carrying a third side (13), said first, second and third sides substantially constituting an open triangle, said first side being thicker than said second side and said third side, the free edge (13b) of said third side (13) extending beyond the free edge (12b) of said second side (12),

- winding said profile on a mandrel so as to form a first turn (S ₁ ), said third side (13) of said profile being disposed against the surface of said mandrel, said first and second sides (11, 12) constituting a groove, - winding said profile onto said mandrel so as to form a second turn (S ₂ ), said free edge (12b) of the second side (12) of said second turn being disposed along said second edge (1 Ib) of the first side (11). ) of said first turn (S ₁ ), and simultaneously solder said free edge of the second side of said second turn to said second edge of the first side of said first turn.