A sealing plug for an electrical cable against air infiItrations into buiIdings and an eleclrica1 cable laying-out method The field of the invention is related to the problem of air infiltrations into buildings through inlets and outlets of cables, tubes and other electrical conducts,. in particular, but not exclusively into the external thermal shells of such buildings.

The interest given today to the energy efficiency of buildings and, more generally, to the so-called green, buildings, is not any more to be emphasised. The part of the electrical equipment in the air infiltrations into buildings is very important. The reason lies in the incomplete or faulty application of the materials and other devices being used to provide sealing around cables and conducts, without mentioning their quite small lifetime. Foam, due to the lack of adhesion thereof, does not provide a good sealing, mainly on composite materials. The adhesive tapes are long to be laid out, as well as the embedding housings. The qualities of the operators are also taken into account.

Considering an electrical cable crossing a wail inside a conduct, the sealing should be provided:

a} on both inner and outer ends of the conduct _f

b) inside the conduct, and

c) between the wall and the conduct.

To give the right ideas, the word "conduct" .means here the tube where an electrical cable extends, ail the same being sheathed for insulation reasons, and which, is built-in within the shells, walls and partitions, the sheathed electrical cable being able as far as it is concerned to be (removed out of its conduct so as to be replaced.

For the inside of the conduct, it has already been suggested to use flexible plugs, but they are exclusively dedicated to such application.

For the conduct surrounding, silicone or foam can be used, but such solutions are more and more rejected by the agreement organisations.

For any new building in Europe, a sealing or infiltroraetry test should, be carried out from now on.

In such, conditions, the Applicant has looked for a universal solution, i.e. being able to be applied for any of the three above-mentioned sealing types (a, b, c) and thus has proposed the present invention.

The invention thus relates first of ail to a sealing plug for preventing air infiltrations via an electrical cable inlet or outlet through a building shell or partition, the plug being tubular, arranged to cross the shell, provided on the external side with a pierceable plugging and sealing membrane and the plug being made of a flexible material.

The plug is adapted to be introduced into a hole being bored through a building shell, such as an external thermal shell of the building or a building partition, i.e.. an inner wall or an inner partition of the building. Generally, the plug provides air sealing, such sealing serving for thermal insulation in the esse of an external shell of the building, and for acoustic insulation and air quality preservation in the case of a partition. The plug enables in fact to avoid exhaust air to flow from the inside of a hollow wall crossed by the plug up to the inside of a building room. The plug is tubular with a through- passing central boring, for receiving a conduct or an electrical cable, the external wall thereof matching with the wail of the hole bored through the shell or the partition of the building. The plug is made of a flexible material due to the fact that the conducts are not rectilinear, that the plug can perfectly suit to passing holes of different diameters, even if a plurality of plugs can be envisaged, each one only for a given range of hole diameters, without affecting anyway the universal character of the plug, and that a passing hole is not necessarily clean. The plug comprises an external plugging -membrane that can be pierced by a cable or an electrical conduct threaded into the plug.

Such membrane is preferably pre~boreo with an electrical cable or wire passing orifice. This allows in particular the invention to be used for passing a flexible electrical cable or wire, which is not sufficiently stiff to be able to be used for piercing the membrane. This also allows to reduce the effort being necessary to cross the membrane with a wire or a cable, the orifice being able to create a breaking initiation and guiding the cable or the wire upon crossing the membrane . The diameter of such orifice is preferably smaller than the diameter of the electrical cable or wire adapted for crossing the plug membrane. Such diameter may be larger than 0.1 ram and is for example comprised between 0.1 and 1 cm.

It should be noticed that the plug could naturally receive one or more electrical cables. Typically, the plug has a diameter comprised between the external diameter of the conduct, on. which it is adapted to be mounted or made and a diameter increased by about 20 mm. with respect to the diameter of the conduct. The plug can for example have a diameter comprised between 10 and 100 mm, preferably between 10 and 70 ram, more preferably between 20 and 40 nun. Its length depends in particular on the application being envisaged. In the case where it is used in art inner partition of the building, it may have a length comprised between 45 and 150 mm. In the case where it is used in an external building shell, it -nay have a length corfiprised between 100 and 400 mm. The material thereof is preferably elastically deformable. The plug is for instance made of EPDM, It has preferably a hardness comprised between 40 and 70 Shore A, for example 60 Shore A.

In a preferred embodiment of the sealing plug according to the invention, the external wall thereof is rugged so as to suit better to the diameter and the surface condition of the wall of the passing hole, in which it is to be introduced.

More preferably, the external wall of the sealing plug comprises radial fins, which may have different diameters and different thicknesses (for instance, comprised between about 0.5 and 2 ram). The fins can have any shape and be for instance rectilinear, undulated, etc. The fins can be interconnected by longitudinal or slanted webs, thereby defining small cavities between the fins and thus limiting the risks of a thermal bridge across the shell or the partition. Such radial fins provide the cooperation between the external wall of the sealing plug and the wall of the passing hole, in which it is to be introduced. The plug thus adheres to the wall of the hole. Moreover, the plug can easily extend through two separate portions of the external thermal shell of a building. Thus, there is no loss of sealing staterial as it was the case when such material was injected with a gun .

In a preferred entbodiment of the sealing plug according to the invention, its internal wall is ragged. It can comprise radial ribs. This allows the plug behavior on the cable passing sheath or conduct to be improved, in particular when the plug is assembled on the sheath. This is particularly advantageous, since, when the membrane of the plug is crossed by an electrical wire or cable, it can foe envisaged for the plug laying-out operator to be able to draw on the cable or the wire so as to adjust its length going beyond the plug, with no risk for the latter to be separated from the sheath, even when such operation is blindly carried out. The radial ribs are preferably flexible ana deferrable.

Advantageously, the sealing plug according to the invention comprises at least one external sealing collar in abutment with the external thermal shell, into which the plug is supposed to be introduced.

The sealing plug can comprise an extension extending beyond the collar so as to be able to be anchored in a facade coating panel.

The plug can comprise at least two axial tubular parts, a first part being open on both axial ends thereof, and a second part being open on one of the axial ends thereof and closed on the other of the axial ends thereof (thus forming a pieroeabie plugging membrane} , both parts being independent or connected together so as to form one single part, which could be cut in order to be able to share the parts from each other.

The sealing plug can correspond to a third tubular part being open on both ends thereof, one of the ends thereof bearing an external sealing collar.

As described more in details in what follows, this is particularly advantageous, since one, two or three tabular parts can foe used depending in particular on the mounting mode of the electrical cables and the thickness of the thermal shell of the building to be crossed. By the way, each tubular part has a smaller length than a complete plug {made of the assembly of the above mentioned parts) and is thus easier to be used than a complete plug and, in particular, to be embedded into a cable passing conduct or sheath.

The present invention also relates to an assembly comprising a sealing plug as above described and a tubular electrical cable passing sheath, which can be ringed or not, the pl¾g being for instance mounted on an end of the sheath. The sheath can have a diameter comprised between 10 and 50 mm and has typically a diameter of about 16, 20, 25, 32, 40 or 50 mm.

The sheath can be made of a plastic material or a metal being quite stiff and be made flexible through its ringed shape. The plug in a flexible material allows the sheath some flexibility to be preserved. The sheath is in particular a sheath fraction, i.e. a sheath of a predetermined length, thereby avoiding the operator to out the sheath before laying-out .

Advantageously, the external wall of the plug comprises radial fins and an annular groove on the basis of at least one side of each of such fins, the fins being deformabie and each groove being shaped to receive at least one part of the fin corresponding to the deformed condition. This enables to facilitate, maybe to make possible the insertion of the plug into the hole of the shell or the partition. The groove can have a determined width depending on the radial height of the corresponding fin so that such fin may be engaged into such groove over substantially the whole height thereof in a deformed position. The groove can have a determined depth depending on the axial thickness of the corresponding fin so that such fin can be engaged into such groove over substantially the whole thickness thereof in a deformed position.

The invention still relates to a method for manufacturing such assembly, wherein the sheath is embedded into a prefabricated plug or the plug is made on the sheath, for instance by over-moulding. The fabrication of the plug directly on the sheath enables in particular to make a unique product comprising a {pre-cut) sheath fraction and a plug and thus avoids the plug to be mounted on the sheath, thereby reducing the laying-out time, since the operarator does not need to cut the sheath and to mount the plug on the cut sheath. This also allows the plug to be anchored on the sheath, the plug material being able to be inserted between the rings of the sheath. The invention also relates to a laying-cat method for at least one electrical cable through a shell or a partition in a building so as to prevent air infiltrations through the cable passage through the shell, wherein a through-hole is bored in the shell or the partition, the plug is then mounted on a cable passing sheath or on the cable, and then the assembly is inserted into the hole.

In a particular case of an embodiment of the invention, the laying-out method contprises les steps consisting of;

1) boring a passing hole through the shell,

2} threading the cable and possibly a cable conduct into the passing hole,

3) threading the cable into a sealing plug according to the invention and boring the plugging merabrane thereof, and the case being,

4) driving the sealing plug into the passing hole, and

5} correctly positioning the cable for the electrical application being considered.

In another particular case of an embodiment according to the invention, the laying-out method comprises the steps consisting of;

1) boring a passing hole through the shell, 2} threading the plug into the conduct, 3} threading the assembly into the hole,

4) threading the cable into the conduct until it passes across the plugging membrane of the plug, and

5) correctly positioning the cable for the electrical application being considered. When the cable extends inside a conduct, the conduct may abut against the plug inside, the plugging membrane being then bored by the cable crossing the plug, but it may be some circumstances where it is the conduct that, after boring the membrane, crosses the plug with the electrical cable inside, in the case for example where the electrical application is distant from the building shell .

The invention will be better understood on reading the following description of various embodiments of the sealing plug, referring to the accompanying drawing, wherein;

- Fig. 1 is an exploded perspective view of an external thermal building shell showing the application of the invention;

- Fig. 2 is an axial sectional view of a first embodiment of the plug according to the invention ;

- Fig. 3 is an enlarged view of a detail of the plug on Fig. 2;

- Fig, 4 is a perspective view of a second embodiment of the plug according to the invention;

- Fig, 5 is a sectional view of the plug on Fig. 4 in its use condition;

- Fig. 6 is a perspective v ; ev of another embodiment of the plug according to the invention;

- Fig. 7 is a partial perspective view of the plug on Fig. 6 being mounted on a ringed tubular sheath;

- Fig. 8 is a partial view of the closed end of the plug according to Fig. 6;

- Fig. 9 is a very schematic sectional view of a shell crossed by an electrical cable, and represents several mountings for such cable; - Fig. 10 is a perspective view of another embodiment of the plug according to the invention;

- Fig. 11 is an axial sectional view of manufacturing means via an over-raouiding of a plug according to the invention;

- Fig. 12 is a sectional view according to line ΧIΙ-Χ1I of Fig . 11; and

~ Fig. 13 is a perspective view of a plug in two parts toeing overmoulded on a ringed tubular sheath .

Referring to Fig, 1, the sealing plug 1 is adapted to prevent air infiltrations inside a building due to the electrical connection of a wail, bracket 2 fastened to the outside of the external thermal shell 3 of the building, said connection being made here with a set of electrical cables 4 extending inside a conduct 5 (such as for example an transversally ringed bendabie insulating TRBI sheath) and are coming from an electrical panel, not shown . It could have been only one cable.

The shell 3 comprises from the inside towards the outside a panel 6 made of a brittle material covering a service space 7, wherein there are the conduct 5, an inside insulating panel £ , forming the service space with the panel 6, a wail 9 in a hard material, here in concrete, against which the panel 8 has been applied, and an outside insulating panel 10 applied against the wail 9. In the case being shown, an external facade coating 11, being distant from the panel 10, completes the shell 3 for substantially esthetics! reasons.

The sealing plug 1 extends through the shell :\, from the inside insulating panel 8 up to the outside insulating panel 11. The panel 6 and the coating 11 have been laid oat after the insertion of the conduct 5 .into the plug 1 and the passage of the cables 4 through the plug and the facade coating 11.

Referring to Fig. 2, the sealing plug 1 is a tubular eleraent with an axis 12 and which comprises, on the outside, a sealing and abutting collar 13.

In fact, the collar 13, which is here a double collar, abuts against the external side 17 of the external insulating panel 10, The collar 13 is plugged in the centre thereof by a pierceable sealing membrane 14.

After boring passing holes 30 in the different panels 8, 9, 10 of the shell 3, said holes being naturally in a mutual alignment, the conduct 5 is then threaded, see cables (4) , before threading the cables 4 into the plug until they bore the sealing membrane 14 of the plug 1. Then, the conduct 5 is threaded into the plug 1 until the conduct 5 abuts against an internal annular shoulder 16 of the plug, near the collar 13, as shown on Fig, 2. On such figure, the cables 4 have not been represented. Then, the sealing plug 1 is driven into the passing holes 30 from the outside and the cables 4 are extracted from the conduct 5 in the appropriate length, by drawing or pushing them, to be able to connect the wall bracket 2, i.e. the electrical application being concerned .

In other words, the cables 4 are correctly positioned in the plug 1.

Finally, the plug 1 is well pushed against the panel il until the collar 13 abuts against the side 17 of such panel 11. In other words, the plug 1 is correctly positioned in the shell 3,

The plug 1 is a flexible material. That could be an elastomer, a thermoplastic, a silicone or a rubber/EPDM system. The plug can be manufactured by injection in a mould.

The internal wall 18 and the external wall 19 of the plug 1 are ragged. In fact and mor¾ particularly, the internal wall comprises small radial ribs 20. In the case where the cable conduct 5 has au external wail with alternating radial grooves 21 and ribs 22, as it is the case here (Fig. 3), the radial rifos 20 of the plug can be embedded into the radial grooves 21 of the conduct and provide a sealing between the plug and. the conduct. It is the above mentioned sealing b) .

The external wail 19 of the sealing plug 1 comprises radial fins of different diameters and thicknesses. For moulding reasons, the fins of a same type are uniformly distributed along the plug. Referring to Figs. 2 and 3, the plug 1 thus comprises quite thin large fins 23, on the flank of which a small annular skirt 24 of a lesser diameter has been mounted. The plug comprises small fins 25 which are a bit thinner and with a quite small diameter. Between both, pairs of thick ribs 26 of a small diameter and being dissymmetric, spaced apart by a groove 2? are mounted.

All those radial fins and ribs provide a cooperation between the external wall 19 of the plug 1 and the wall 28 of the passing hole {s> , in which it is inserted. It is the above mentioned sealing c) - ¾s regards the sealing a) also above mentioned, it is provided by the plugging rrtemforane only bored by the cables or the electrical connection conduct .

It is to be noticed that, by application of the collar' 13 against the shell 3 of the building, a sealing part c) as above defined is provided.

In the embodiment 100 of the sealing plug according to the invention on Figs. 4 and 5, on which the elements being similar to those of the plug 1 on Figs. 2 and 3 bear the same numerals increased by one hundred, the plug extends beyond the collar 113 so as to be able to also be anchored into a facade coating panel 11 through an extension 129. In the example being considered, the external wall of the extension 129 is also rugged, but not by fins, but by notching ribs 130.

It will be noticed referring to Fig, 5 that the sealing between the plug 1 and the shell 3 is made thanks to the radial fins 123, 125 of the plug 1, to the central over-thickness 131 of the collar 113 in abutment against the external edge 132 of the passing hole in the hard material wall 9 of the shell 3 and also to the peripheral extra sealing washer 133 also in abutment against the external side 134 of the wail 3.

In the embodiment 200 of the sealing plug according to the invention of figs.. 7 and 8, on which the elements being siridlar to those of the plug I frost Figs, 2 and 3 bear the same reference annotations increased by two hundreds, the plug is of a cleavable type and comprises three coaxial tubular parts A, B and C, which can be separated from each other. The parts A, B and C are arranged end to end and are interconnected by cutting or deferrable bridges of material 240. The parts A, B and C are thus integrally formed ,

In the example being shown, two adjacent parts (A and B, or B and C} are interconnected by at least two diametrically opposed bridges of material 240 with respect to the longitudinal axis of the plug. A bending and/or a torsion of the plug 200 at the level of the bridges of material 240, between two tubular parts, allow such bridges to be deformed and the tubular parts to be separated from each other.

Both axial ends of the part A are open, the first one comprising the collar 213. Both axial ends of the part B are open and identical. One of the axial ends of the part C is open and the other is closed by the membrane 214, being adapted to be bored by one or more cables 204, as shown on Fig. 8.

The parts A, B and C comprise radial fins on their external wails.

In an alternative embodiment being not shown, the parts A, B and C can be separated from each other.

On Fig. 7, the plug 200 is mounted on a conduct 205 such as a ringed tubular sheath. The end of such sheath is preferably in an axial abutment with the membrane 214 {of part C) of the plug 200.

Fig. 9 represents several different mounting modes for electrical cables 204 into a passing hole 230 of a building shell 203. Such electrical cables 204 are connected inside the building (on the left of the shell 203) with the electrical panel and outside the building (on the right of the shell 203) with, an electrical piece of equipment, such as a. wall bracket ,

The different mounting modes will be now described from top to bottom of Fig, 9, In the first mode, the conduct 205 is bent and the cables 204 go out of such conduct at the level of the external opening of the hole 230. In this case, the above- mentioned parts A and. C can be used, part A being first engaged onto the conduct,, and then part C is also engaged onto the conduct so that the cables pierce its membrane 214, Parts A and C are engaged into the hole 230 so that the membrane 214 is substantially aligned, with the external opening of the hole and that the collar 213 abuts on. the internal side of the shell 203.

In the second mode, the conduct 205 presents two successive bends and the cables 204 go out of such conduct beyond the external opening of the hole 230. in this case, the above mentioned parts A, B and C can be used. Such parts are mounted one after the other on the conduct.,, and then they are engaged into the hole 230 so that the collar abuts on the internal side of the shell 203. The membrane 214 and a portion of part C are located outside the hole 230,

In the third mode, the conduct 205 is bent, the cables 204 enter the conduct 205 at the level of the internal opening of the hole 230 and leave such conduct beyond the external opening of the hole 230. In this case, parts C, E and C can be used, i.e. parts coming from two plugs 200, These parts are mounted on the conduct and then engaged into the hole 230. The .membrane of the first part C is adapted to be located at the level of the internal opening of the hole and that of the other part C is adapted to be located outside the hole, outside the building. Mounting a part C on each end of the conduct provides a good sealing between the cables and the conduct, and avoids water to be introduced and. accumulated within such conduct .

In the fourth mode, the conduct 205 is straight and stops at the level of the internal and external openings of the hole 230. In this case, two parts C can be used, .i.e. parts C coming from two plugs 200. Such parts are mounted on the conduct, and then they are engaged into the hole 230 so that the membranes 214 of parts C are located at the level of the internal and external openings of the hole.

In the last fifth mode, the conduct 205 presents two successive bends, one single part B being used. Such part B is mounted on the conduct, and then is engaged into the hole 230, so that these ends are substantially located perpendicularly to the internal and external openings of the hole 230. Such mode can be used in a wail inside a building in particular, so as not to alter the acoustical performances of such wail _*

In a mounting position, parts Ά, B and C are preferably located at a mutual axial distance together .

Fig. 10' will be now referred to, which represents another embodiment 300 of the plug according to the invention, on which the elements being similar to these of the plug 1 of Figs. 2 and 3 bear the same reference annotations increased by three hundreds. Such embodiment 300 differs from the one above described in reference to Figs. 6 to 8 in particular in that only the parts B and C are coaxial, the part A being arranged besides and in parallel with parts B and C. Parts B and C are interconnected by bridges of material 340 of the above mentioned type. Other bridges of material 342 connect the part A with the parts B and C. The part A comprising the collar 313 has a length close to the cumulated lengths of parts B and C, the part C comprising the collar 314.

The plug 300 includes radial fins 323, 325 and annular grooves 344 on its external wall. The radial fins 325 are substantially regularly distributed on the length, of each part A, B and C. Moreover, each part comprises in. the vicinity of each of its ends at least one radial fin 323 of a larger diameter than the fins 325 and which is adapted to improve sealing between the plug and. the internal wail of the passing hole, in particular because of the conical shape of the hole opening corresponding to the drill outlet upon the hole boring (cons effect) .

At least one annular groove 344 is present on the bass of each fin 323, 325, such groove being adapted to reduce the insertion effort and to facilitate the insertion of the corresponding tube part by making the distortion of the fin 323, 325 easier on the side of such groove. A groove is thus located on either one or both sides of one fin, in particular depending on the mounting and insertion direction of the tubular part into the passing hole. The parts B and C can be engaged through one side or the other into a passing hole of a shell, grooves can thus be arranged on each side of the fins. On the contrary, the part Ά can only be engaged into a hole through its end being opposed, to the collar 313. The grooves 344 are thus formed on only one side (oft the left in the drawing) of the fins so as to make their distortion easier on the collar side.

Figs. 11 and 12 represent a method for making a plug: according to the invention, .such plug; 5-08 being made in situ an one ehd of a. ringed tubular sheath 505. The method consists in over-moulding the plug directly on the sheath 505 by means of a mould 550 comprising at least two parts defining between them an internal boring 552, into which a cylindrical spindle 554 supporting the sheath 505 is supposed to be engaged, the internal walls of the boring 552 defining a plug forming print. The mould comprises internal channels 556 for inserting melted material into the print. The mould can comprise one or more sets of such channels extending on one or more sides of the mould.

As it is visible on Fig, 11, the channels 552 open into the print at the level of the radial fins 525 to be shaped of the external wall of the plug 500. Moreover, due- to the ringed form of the sheath 505, the liquid material being injected into the mould will enter the inter- fin spaces and thus shape the radial fins of the internal wall of the plug .

The sheath 505 is crossed by the spindle 554 and is preferably Maintained stationary on the spindle 554 by means of plots 556 radially abutting on the sheath so as to maintain it tightened on the spindle. Such plots 558 are visible on Fig. 12 and the abutting areas 560 of the plots on the sheath are schematically represented on Fig. 11. These plots 558 are handled from the outside of the mould and radially cross the mould until they abut against the sheath. Due to such abutment, no liquid material will be injected at the level of the areas 560 and the plug 500 will thus include radial voids, which will however not foe prejudicial to sealing In the cable passing hole.

The manufacturing method can be implemented in the following way. The sheath 505 or a sheath fraction is engaged onto the spindle 554, and then the spindle is engaged into the boring 552 of the mould. The sheath is maintained, in abutment on the spindle by the abutment plots 558. The mould is her-net icaliy sealed, end then, the liquid material is injected through the channels 556 into the mould so as to over- mould the plug 500 over the sheath. After plug curing, the mould is disassembled so as to remove the plug.

The spindle 554 has for instance a length of about 400 ram.

Fig. 13 shows a piug 500 in two parts (of the types A and B as above mentioned) that have been overmoulded through the above mentioned method directly over a sheath 505. Both parts A and B are distant from each other and comprise each external radial fins 525 and radials voids corresponding to the abutment areas 560 of the above mentioned plots.