FR3140318A1 - Trim for vehicle seat element and method for producing such a trim - Google Patents

Abstract

A trim (15; 18) for a vehicle seat element (13; 16) comprises a first trim module (42) with a first cushioning piece (48) and a second trim module (38; 40) with a second quilting piece (44; 46). The first trim module (42) and the second trim module (38; 40) are adapted to be attached to a frame (14; 17) of the vehicle seat element (13; 16), independently one the other. At least one of the first padding piece (48) and the second padding piece (44; 46) comprises a tangle (86) of fibers (80), forming loops welded together, the fibers (80) being made of a material including a thermoplastic polymer. Abstract figure: [Fig. 3]

Description

Trim for vehicle seat element and method for producing such a trim

The present description relates to a trim for a vehicle seat element and to a vehicle seat element comprising such a trim. The present description also relates to a method of producing such a trim for a vehicle seat element.

A motor vehicle seat conventionally comprises a frame and a trim, fixed to the frame. The trim may comprise several trim elements, each trim element being specific to a respective seat element, such as a backrest, a seat, a headrest or an armrest of the vehicle seat.

The upholstery of a motor vehicle seat element generally includes padding. The padding of a seat element is conventionally made of urethane polymer foam (or polyurethane, PU), in particular polyurethane foam obtained from polyeter/polyol (or PUR) type polyols. These foams can be shaped in molds relatively easily, to form different shapes of padding for different vehicle seat elements, such as the seat or the backrest, for example.

Polyurethane foam padding is satisfactory, but can retain moisture, especially in humid conditions. This may cause a feeling of discomfort for an occupant of the vehicle seat, an element of which includes such padding.

In addition, polyurethane foam is conventionally made by mixing, among other things, polyols with isocyanates. The chemical reaction carried out emits CO ₂ to form a foam, the CO ₂ emitted contributing to global warming.

Furthermore, polyurethane foam is not recyclable.

Also, it appears desirable to limit the use of polyurethane in the padding of vehicle seat elements.

Summary

This description improves the situation.

To this end, a trim for a vehicle seat element is described, comprising a first trim module with a first cushioning piece and at least one second trim module with a second cushioning piece, the first trim module and the at least one second upholstery module being adapted to be fixed to a frame of the vehicle seat element, independently of one another, at least one of the first cushioning piece and the at least one second piece of padding comprising a tangle of fibers, forming loops welded together, the fibers being made of a material including a thermoplastic polymer.

Thus, advantageously, at least part of the padding of the seat element is made of a material other than polyurethane foam. Advantageously, this material is a recyclable plastic material. This material can also make it possible to produce a piece of padding that is significantly lighter than a similar piece of padding, made from polyurethane foam. The material may also be more breathable, allowing air and possible moisture to pass better through the padding.

According to preferred embodiments, the trim of the seat element comprises one or more of the following characteristics, taken alone or in combination:
- the at least one of the first piece of padding and the at least one second piece of padding comprising a tangle of fibers, forming loops welded together, the fibers being made of a material including a thermoplastic polymer, has a surface intended to be oriented towards an occupant of the vehicle seat shaped by thermoforming;
- the first upholstery module comprises a support, the first piece of padding being fixed to the support;
- the first trim module comprises at least one device adapted to perform a comfort function for the occupant of the vehicle seat, the at least one device being fixed on the support;
- the at least one second pad module comprises a support, the at least one second piece of padding being fixed on the support;
- the lining comprises two second lining modules, each with a respective cushioning piece, the first lining module being intended to be placed between the two second lining modules; And
- each trim module includes a respective cover or in which a single cover is adapted to cover the different trim modules.

According to another aspect, a vehicle seat element is also described comprising a trim for a vehicle seat element as described above, in all its combinations.

The vehicle seat element may be one of:
- a seat ;
- a file ;
- a headrest;
- an armrest;
- a backrest top adjustment device;
- a seat length adjustment device; And
- a set of at least two aforementioned elements.

In particular, the seat element may be a seat or a backrest, and the trim of the vehicle seat element may comprise a first trim module with a first cushioning piece and two second trim modules each with a second piece padding, the first padding module being intended to be placed between the two second padding modules, the first padding piece forming a central part of the padding of the seat element, the two second padding modules forming lateral supports of an occupant of the vehicle seat, such that, preferably, the two second pieces of cushioning protrude relative to a surface of the first piece of cushioning.

According to another aspect, there is described a method of manufacturing a trim for a vehicle seat element as described above, in all its combinations, the method comprising the step consisting of providing a first piece of cushioning and at least one second piece of padding, at least one of the first piece of padding and the at least one second piece of padding comprising a tangle of fibers, forming loops welded together, the fibers being made of a material including a thermoplastic polymer .

The padding piece comprising a tangle of fibers forming loops welded together, the fibers being made of a material including a thermoplastic polymer, can be produced by implementing the steps consisting of:
a) extruding a material comprising at least one thermoplastic polymer in an extrusion die comprising a plurality of extrusion nozzles, to form a curtain of molten fibers;
b) form a tangle of molten fibers, the fibers forming loops welded together;
c) cool the tangle of fibers.

The method may include a step of shaping by thermoforming at least one face of the tangle of fibers intended to be oriented towards an occupant of the vehicle seat.

Other characteristics and advantages will appear from the following description of embodiments, given as non-limiting examples, with reference to the attached drawings. On the drawings:

schematically represents a side view of a first example of a vehicle seat;

schematically represents in perspective the back of the vehicle seat of the ;

schematically represents an exploded view of the vehicle seat back of the ;

schematically represents in perspective the frame of the vehicle seat back of the And ;

schematically represents in perspective a first face of a central trim module support implemented in the vehicle seat back of the And ;

schematically represents in perspective the second face, opposite the first face, of the central trim module support of the ;

schematically represents the central trim module support of the And , mounted on the backrest frame of the ;

schematically represents a perspective view of the vehicle seat back of the And , devoid of the quilting pieces of the different trim modules.

schematically illustrates a first method of producing a cushioning piece which can be implemented in the cushioning of a trim module implemented in the seat back of the And ;

schematically illustrates different extrusion dies that can be implemented in the process illustrated in , and a fiber or a tangle of fibers obtained using each of these extrusion dies;

schematically illustrates a second example of a method of producing a piece of cushioning which can be implemented in the cushioning of a trim module implemented in the seat back of the And ;

schematically illustrates a first stage of the second example of a process for producing a piece of quilting, of the ;

schematically illustrates a second stage of the second example of a process for producing a piece of quilting, of the ;

schematically illustrates a variant of the first method of producing a piece of quilting, of the .

In the different figures, the same references designate identical or similar elements. For brevity, only the elements which are useful for understanding the embodiment described are represented in the figures and are described in detail below.

In the following description, when referring to absolute position qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative, such as the terms “above”, “below”, “superior”, “lower”, etc., or to qualifiers of orientation, such as “horizontal”, “vertical”, etc., it is made reference, unless otherwise specified, to the orientation of the figures or of a vehicle seat in its normal position of use.

In particular, the longitudinal direction X means the longitudinal direction of the seat. The longitudinal direction of the seat is considered to be the same as the longitudinal direction of the motor vehicle in which the seat is mounted. This longitudinal direction X corresponds to the normal direction of travel of the vehicle. The longitudinal direction X is horizontal. The transverse direction Y of the seat thus corresponds to the transverse or lateral direction of the motor vehicle. This transverse direction corresponds to a direction perpendicular to the normal direction of travel of the vehicle. The transverse direction Y is horizontal. Finally, the vertical direction Z is a vertical direction of the seat, perpendicular to the longitudinal and transverse directions.

There schematically represents a motor vehicle seat 10 mounted on a slide mechanism 12 .

The seat 10 comprises a seat 13 , with a seat frame 14 and a seat pad 15 , on which a backrest 16 , with a backrest frame 17 and a backrest pad 18 , is mounted. The backrest frame 17 here pivots around a transverse axis A , relative to the seat frame 14 . To do this, an articulation mechanism 20 is arranged between the seat frame 14 and the backrest frame 17 .

The seat 13 is mounted on movable profiles 22 , also called slides or male profiles, via feet 24 , 26 . Each movable profile 22 is part of a slide 12 and is associated with a fixed profile 28 . The fixed profile 28 is also called a rail or female profile. The fixed profile 28 is fixed to the floor 30 of a motor vehicle.

The seat 10 comprises in this example a manual control element 32 , called a rudder, for sliding control of the slides 12 . This manual control element 32 makes it possible in particular to block and unlock systems for stopping the sliding of the movable profiles 22 relative to the respective fixed profiles 28 . Once the stopping systems have been unlocked, the manual control element 32 can also be used to slide the movable profiles 22 relative to their respective fixed profiles 28 of the slide 12 in the longitudinal direction X of the slides 12 . The fixed 28 and movable 22 profiles of the slides 12 are generally metallic.

Alternatively, the movement of the movable profiles 22 relative to the fixed profiles 28 is controlled by means of an actuator.

According to the example illustrated, the seat 10 may also include a headrest 34 . The headrest 34 may also include a headrest frame 35 and a headrest trim 36 attached to the headrest frame 35 . The headrest frame 35 can in particular be fixed to the backrest frame 17 or slidably mounted in a substantially vertical direction relative to the backrest frame 17 .

As can be seen on the in particular, the illustrated backrest 16 essentially comprises a first lateral trim module 3 8 , a second lateral trim module 40 and a central trim module 4 2 , such that the first and second lateral trim modules 3 8 , 40 are each arranged on a respective side of the central trim module 4 2 . Each trim module 38, 40 , 42 here includes a cushioning piece 4 4 , 4 6 , 4 8 , the only visible element of the respective trim module on the . As is particularly visible on the , the cushioning piece 4 8 of the central trim module 4 2 may include holes 47 . These holes 47 allow ventilation of the back of the occupant of the seat, as will be described later.

In the example illustrated, the central trim module 4 2 forms the support face of the backrest bowl 16 , that is to say the central support part of the back of the occupant of the seat, while the lateral modules 3 8 , 40 form the lateral portions projecting relative to the bowl of this same support face for the back of the occupant of the seat (or bolsters ).

It should be noted here that the trim modules 38 , 40 , 42 pre-exist their attachment to the backrest frame 17 . Thus, these trim modules 38 , 40 , 42 are not produced by overmolding the backrest frame 17 and/or structural elements already secured to the backrest frame 17 . This does not prevent the padding parts 44 , 46 , 48 of the different trim modules 38 , 40 , 42 from being produced by overmolding a possible support for the respective trim module 38 , 40 , 42 . However, this overmolding is carried out before fixing the support in question on the backrest frame 17 .

The backrest 16 also includes a shell 50 , hereinafter referred to as a “rear shell”, defining most of the rear face of the backrest 16 .

Remarkably here and as illustrated schematically by the , each trim module 3 8 , 40 , 42 is fixed to the backrest frame 17 , independently of the two other trim modules 38 , 40 , 42 . In other words, each upholstery module 38 , 40 , 42 can be fixed on the backrest frame 17 while the two other upholstery modules 38 , 40 , 42 are not fixed on the backrest frame 17 . Thus, each trim module 38 , 40 , 42 is able to be fixed on the backrest frame 17 independently of the two other trim modules 38 , 40 , 42 . A trim module 38 , 40 , 42 can however be attached to another trim module 38 , 40 , 42 . However, preferably, the trim modules 38 , 40 , 42 are independent in that there is no direct attachment of a trim module 38 , 40 , 42 to another trim module 38 , 40 , 42 . The padding piece 48 of the central trim module 42 can however be mounted tight between the padding pieces 44 , 46 of the two side trim modules 38 , 40 .

The rear shell 50 can also be directly fixed to the backrest frame 17 , preferably independently of the trim modules 38 , 40 , 42 . The rear shell 50 can be fixed to the backrest frame 17 by any suitable means, in particular by screwing or riveting. According to yet another example, the rear shell 50 is fitted elastically onto the backrest frame 17 . Advantageously, the rear shell 50 is adapted to be fixed on the backrest frame 17 after fixing the trim modules 38 , 40 , 42 . This can in fact allow access from the rear of the seat 10 , to the different elements of the trim modules 38 , 40 , 42 which must be functionally connected, after the trim modules 38 , 40 , 42 have been fixed on the backrest frame 17 , before fixing the rear shell 50 .

As illustrated in , the backrest frame17essentially comprises a first amount17 ₁ , a second amount17 ₂ , a first crossing17 ₃ , hereinafter called “low crossbar17 ₃ ”, and a second crossbar17 ₄ , hereinafter called “high crossbar17 ₄ ". The amounts17 ₁ ,17 ₂ and the sleepers17 ₃ ,17 ₄ form a backrest frame17in the form of a frame. To do this, the amounts17 ₁ ,17 ₂ , and the sleepers17 ₃ ,17 ₄ can be fixed together, in particular welded together. Alternatively, the backrest frame17is in one piece, this being for example molded.

On the backrest frame 17 , the central trim module 4 2 illustrated in And , respectively in front view and in rear view, without the associated cushioning piece 48 .

In these figures, the central trim module 4 2 essentially comprises a support 5 2 , here in the form of a plate. The support 5 2 is notably more rigid than the cushioning piece 4 8 of the central trim module 4 2 . The padding piece 4 8 of the central trim module 4 2 is fixed on the support 5 2 . In particular, the padding piece 4 8 can be overmolded on the support 5 2 . Alternatively, the padding piece 48 can be glued or fitted elastically onto the support 5 2 , the padding piece 4 8 preferably having plastic inserts in the latter case, forming elastic nesting reliefs on the support 5 2 .

The support 52 is for example made of ABS (acrylonitrile butadiene styrene) and/or PC (Polycarbonate) and/or P/E (Polypropylene/Polyethylene copolymer).

The support 52 extends essentially in a longitudinal direction. The longitudinal ends 5 2 ₁ , 5 2 ₂ of the support 5 2 are here curved. Thus, the upper end 5 2 ₂ of the support 5 2 can rest on the upper crosspiece 17 ₄ of the backrest frame 17 , as illustrated in [ ]. Similarly, the lower end 5 2 ₁ of the support 5 2 can receive the lower crosspiece 17 ₃ of the backrest frame 17 as is visible on the . The ends 5 2 ₁ , 5 2 ₂ here present means for fixing to the lower 17 ₃ and upper 17 ₄ crosspieces, respectively, of the backrest frame 17 . These fixing means may in particular include:
- additional reliefs, for example for forceful fixing of the central trim module 4 2 on the backrest frame 17 ; and or
- corresponding holes for fixing using screws, bolts or rivets, for example; and or
- complementary elastic interlocking reliefs (or clips), for fixing by elastic interlocking.
This last solution appears to be the most favorable, which limits the number of parts and manipulations necessary to fix the support 5 2 on the backrest frame 17 .

As can be seen on the has , the support 5 2 can be equipped with different elements each associated with one or more comfort functions for the occupant of the seat 10 .

Thus, according to the example illustrated, an air guide 54 is fixed to the support 5 2 , in a sealed manner. The air guide 54 comprises holes 54 ₁ intended to be arranged substantially opposite the holes 47 in the cushioning piece 4 8 of the central trim module 4 2 . This air guide 54 is arranged at a through opening in the support 5 2 , a fan 56 being fixed on the opposite face 5 2 B of the support 5 2 to blow air into the air guide 54 . Advantageously, the air guide 54 can have an ergonomic shape ensuring more comfortable reception of the back of the occupant of the vehicle seat. This function of more comfortable reception of the back of the occupant of the seat can, alternatively, be provided by a separate element of an air guide 54 .

Furthermore, inflatable pockets 58 , 60 are fixed on the support 5 2 , here on the face 5 2 A of the support 5 2 intended to be oriented towards the back of the occupant of the seat 10 . In the example illustrated, the inflatable bags 5 8 , 6 0 are substantially regularly distributed on the support 5 2 , in a matrix. In the example of the , eight inflatable pockets 5 8 , 6 0 are thus distributed in four lines of two columns of inflatable pockets 5 8 , 6 0 . The eight inflatable bags 58 , 60 can be supplied with air selectively by an air pump 62 , via a valve 64 . Thus, by controlling the valve 64 according to a particular inflation pattern of the inflatable bags 5 8 , 6 0 , it is possible to obtain a massaging effect on the back of the occupant of the seat 10 . Alternatively, all the inflatable pockets 5 8 , 6 0 can be supplied with air simultaneously, in particular to improve the support of the back of the occupant of the seat, the inflatable pockets 5 8 , 6 0 inflating until they adapt to the shape of the seat occupant's back. According to yet another alternative, part of the inflatable pockets 5 8 makes it possible to massage part of the back of the occupant of the seat 10 , in particular the upper part of the back, while the other part of the inflatable pockets 6 0 essentially provide a function for supporting the back of the occupant of the seat, in particular a function of maintaining a lower part of the back of the occupant of the seat.

Other comfort functions can be associated with the support 5 2 . In particular one or more speakers and/or one or more vibrating devices (or vibrators, from the English “ exciter ”) and/or one or more resistive wires for heating the back of the occupant of the vehicle seat 10 can be fixed on the support 5 2 . Preferably, the speaker(s) and/or the vibrating device ( s ) and/or the resistive wire(s) are arranged between the support 52 and the cushioning piece 48 of the central trim module 42 or at least partially received in the cushioning piece 4 8 of the central trim module 4 2 .

Preferably, all the elements fixed to the support 5 2 requiring an electrical supply and/or a control from outside the seat and/or a transfer of information to the outside of the seat are electrically connected to a single connector 66 ensuring the connection with the exterior of the seat 10 . Thus, the assembly of the seat 10 is greatly simplified, which only requires an electrical connection between the exterior of the seat 10 and the connector 66 to electrically power, control and communicate with the adapted elements of the central trim module 4 2 . The connector 66 is advantageously arranged on the face 5 2 B of the support 5 2 intended to be opposite the back of the occupant of the seat 10 .

Furthermore, as is visible in particular on the , on each upright 17 ₁ , 17 ₂ of the backrest frame 17 , is fixed a support 67 , 68 of the first side trim module 38 and the second side trim module 40 , respectively. Each of the supports 67 , 68 can be fixed to the associated upright 17 ₁ , 17 ₂ by elastic fitting and/or screwing and/or riveting and/or force fixing, in particular.

On each of the supports 67 , 68 is fixed the cushioning piece 44 , 46 associated with the first or second lateral trim module 38 , 40 . In particular, each piece of padding 4 4 , 4 6 can be overmolded on the respective support 67 , 68 . Each piece of padding 44 , 4, 6 can alternatively be glued or fitted elastically onto the associated support 67 , 68 . In the latter case, the cushioning pieces 44 , 4 6 may include plastic inserts.

An inflatable pocket 7 0 , 7 1 of a device for adjusting the lateral support of the back of the occupant of the seat is fixed on each support 67 , 68 of the lateral module.

On the support 67 of the first side trim module 3 8 illustrated in , is fixed an inflatable bag 70 and a pump adapted to inflate the inflatable bag 7 0 . The inflatable pocket 7 0 has a comfort function rather than safety, in that it can allow a massaging effect and/or better adaptation of the shape of the side trim module 3 8 to the occupant of the seat 10 . An air pump can also be fixed on the support 68 of the other side trim module 40 , in order to inflate the associated inflatable bag 7 1 . Advantageously, in fact, an air pump is arranged in each lateral trim module 3 8 , 40 to avoid an air connection between a trim module 3 8 , 40 , 4 2 and another 3 8 , 40 , 4 2 .

Each side trim module 3 8 , 40 can also be equipped with a side airbag device 72 (or side airbag). Each side trim module 3 8 , 40 can be pre-equipped with such a side airbag device 72 before assembly on the frame.

Here again, the side trim modules 3 8 , 40 can include other comfort functions.

As for the central trim module 4 2 , the elements of each lateral trim module 3 8 , 40 requiring an electrical power supply, control or transfer of information, are preferably electrically connected to a single connector of each lateral trim module. garnish 3 8 , 40 . This simplifies the assembly of the seat back.

The backrest 10 as it has just been described is particularly simple to assemble.

Thus, a method of assembling such a backrest can comprise a first step consisting of providing a backrest frame 17 and the three trim modules 38 , 40 , 42 . At this stage, the backrest frame 17 may possibly already be fixed on the seat frame 14 and/or have already received the headrest frame 35 in whole or in part. In particular, the support rods of the headrest 34 can already be fixed on the backrest frame 17 .

Secondly, the trim modules 38 , 40 , 42 are fixed on the backrest frame 17 . The order of fixing the trim modules 3 8 , 40 , 4 2 may depend on the geometry of the supports 5 2 , 67 , 68 of the different trim modules 3 8 , 40 , 4 2 and their fixings on the frame of file 17 , in particular. According to the example of file described previously, we can for example start by fixing the central trim module 4 2 , then the two side modules 3 8 , 40 . Alternatively , however, the central trim module 42 can be fixed after the two side modules 38 , 40 .

It should be noted that these successive fixings can be carried out in whole or in part by a machine. In particular, the central trim module 4 2 can be “stuck” on the upper cross member 17 ₄ of the backrest frame 17 , then the lower end 5 2 ₁ can be fixed on the lower cross member 17 ₃ of the back frame. file 17 . By “stacked”, we mean here that the folded end 5 2 ₂ of the support 5 2 of the central trim module 40 comes to rest on the upper crosspiece 17 ₄ of the backrest frame 17 , complementary reliefs of the end folded 5 2 ₂ of the support 5 2 , on the one hand, and of the backrest frame 17 and/or the headrest frame 35 , on the other hand, guiding an essentially rotational movement of the support 5 2 relative to a transverse axis of extension of the upper crosspiece 17 ₄ of the backrest frame 17 . Here, for example, notches made at the end 5 2 ₂ of the support 54 and receiving the headrest support rods 35 allow the movement of the central trim module 4 2 to be guided relative to the backrest frame. 17 .

We then make the necessary electrical and even air connections. Preferably, there is only one electrical connection to be made for each trim module 3 8 , 40 , 4 2 .

Finally, the rear shell 50 is fixed on the backrest frame 17 . Here again, the order of fixing the rear shell 50 may vary.

Thus, the assembly of the seat 10 is very simple to carry out. In addition, it may be identical or substantially identical, regardless of the functions integrated or not in the file 16 . It is thus possible to provide a single automaton to mount a wide variety of distinct vehicle seat backs, always with a substantially equal assembly time. The assembly line for such a range of seats is thus simpler and easier to manage.

It should also be noted that a trim module 3 8 , 40 , 4 2 can easily be changed, without having to change the other trim modules 3 8 , 40 , 4 2 , or even without having to dismantle them. It may be interesting, for example, to replace the central trim module 4 2 with a central trim module 4 2 accommodating one or more new comfort functions compared to the old central trim module 4 2 . In this case, not dismantling the side trim modules 38 , 40 means not touching the safety functions of the seat which are the two side airbags present in or associated with the side trim modules 38 , 40 . This limits the risks of failure of these safety systems after the operation of replacing the central trim module 4 2 .

Furthermore, remarkably, at least one piece of padding 44 , 46 , 48 of the filling modules 38 , 40 , 42 , is formed by an entanglement (or cluster) of fibers forming loops welded together, the fibers being in a material including a thermoplastic polymer, preferably made of thermoplastic material/x//s/. The fibers – and therefore also the loops – can have an irregular distribution in the tangle of fibers, in particular a random distribution. According to a first example, the padding piece 48 of the central trim module 42 can be formed by such an entanglement, and the padding pieces 44 , 46 of the side trim modules 38 , 40 are made of polyurethane foam. According to a second example, the padding pieces 44 , 46 of the side trim modules 38 , 40 are each formed by an interlocking as described above, the padding piece 48 of the central pad module 42 being made of polyurethane foam. According to a third example, each of the padding pieces 44 , 46 , 48 of the trim modules 38 , 40 , 42 is formed by an entanglement as described above.

The tangle of fibers forming the quilting piece 44 , 46 , 48 may comprise, preferably consist of, a tangle of continuous fibers, in three dimensions ("3D"). The fibers are called “continuous” here in that their length is very much greater than their diameter. For example, the ratio between the length of the fibers and their diameter can be at least equal to 100, preferably 500, and more preferably 1000. Preferably, the fibers extend from a first end onto a first edge of the tangle, to a second end on a second edge of the tangle, opposite the first edge. In addition, the diameter of the fibers can be between 0.2 mm and 2 mm, preferably between 0.3 mm and 1.5 mm. The tangle of fibers is described as "three-dimensional", because the thickness of the tangle of fibers obtained is not negligible, in that it is preferably much greater than the diameter of the fibers. The thickness of the tangle of fibers obtained is in particular at least 10 times greater, preferably at least 30 times greater, more preferably at least 50 times greater, than the diameter of the fibers of the tangle of fibers.

The fibers here are made of a material including at least one thermoplastic polymer. For example, the fibers are made of a material comprising at least 95% by weight of polyethylene terephthalate (or PET). For example again, the fibers are made of a material comprising:
- 95% to 99% by weight of a first polymer from the polyester family such as PET; And
- 1% to 5% by weight of a second polymer from the polyester family such as polytrimethylene terephthalate (or PTT) or polybutylene terephthalate (or PBT). According to one embodiment, the fibers are made of a material including only two materials, PET, on the one hand, and PTT or PBT, on the other hand.

The tangle of fibers forming the padding piece 44 , 46 , 48 may have an apparent density of less than 20 kg/m ³ . Alternatively, the tangle of fibers forming the padding piece 44 , 46 , 48 has an apparent density greater than or equal to 20 kg/m ³ , preferably greater than or equal to 30 kg/m ³ , more preferably greater than or equal to at 45 kg/m ³ , and/or less than or equal to 70 kg/m ³ , preferably less than or equal to 65 kg/m ³ .

Preferably, the space between the fibers of the tangle of fibers forming the padding piece 44 , 46 , 48 is left free, filled only with air or any other ambient gas. In other words, it appears preferable not to fill the space between the fibers of the tangle of fibers by means of a liquid material, in the form of a gel or liquefiable solid, for example poured between the fibers. Indeed, by keeping the space between the fibers free, a particularly breathable piece of padding 44 , 46 , 48 is obtained, the space between the fibers promoting the circulation of air in the padding piece 44 , 46 , 48 . In particular, such a piece of padding 44 , 46 , 48 can have better breathability than a piece of polyurethane foam padding. Such a piece of padding 44 , 46 , 48 also has the advantage of absorbing significantly less moisture than a piece of polyurethane foam padding.

The tangle of fibers forming the padding piece 44 , 46 , 48 may in particular have a thickness greater than or equal to 30 mm and/or less than or equal to 60 mm.

A first example of a method for producing a piece of padding 44 , 46 , 48 is illustrated in .

According to the example illustrated in , the process, here continuous, comprises a first step consisting of extruding a plastic material containing at least one thermoplastic polymer, in an extrusion die 74 comprising a plurality of extrusion nozzles 76 .

To do this, the extrusion die 74 can be supplied with polymer granules/s/. The extrusion die 74 can for example be adapted to heat the plastic material, in particular the polymer granules/s/, to a temperature between 180°C and 240°C.

According to the example illustrated, the extrusion nozzles 76 are regularly distributed in two perpendicular directions to form a matrix of extrusion nozzles 76 . The extrusion die 74 thus makes it possible to form a curtain 78 of continuous, melted fibers 80 , the density of fibers 80 of which is substantially constant in cross section (that is to say in a plane perpendicular to the direction of advancement extruded fibers 80 ). Here, the extrusion nozzles 76 are distributed in a horizontal plane. Also, to keep the density of the fibers 80 substantially constant in cross section of the curtain 78 of fibers 80 , the fibers 80 are here driven by gravity at the outlet of the extrusion die 74 .

By “curtain 78 of fibers 80 ”, we mean here a configuration of the fibers 80 extending substantially parallel to each other, the fibers 80 being included, in a plane perpendicular to their direction of advancement, in an envelope curve corresponding substantially to the section of the extrusion die 74 , here substantially rectangular. Alternatively, we can speak of a rain of fibers 80 from the exit of the extrusion nozzles 76 .

In a second step of the process, the molten fibers 80 are driven towards two counter-rotating guide members 82 , 84 . Here, the guide members 82 , 84 are identical rollers, in particular of the same, constant diameter. Preferably, the minimum distance between the two rollers 82 , 84 is less than the smallest dimension (or width) of the cross section of the curtain 78 of fibers 80 , while the other dimension of the cross section of the curtain 78 of fibers 80 , the largest (or length), is substantially equal to or less than the length of the rollers 82 , 84 .

Preferably, at the outlet of the extrusion die 74 and upstream of the rollers 82 , 84 , the temperature of the plastic material from which the fibers 80 are formed is greater than or equal to 180° C. and/or less than or equal to 240° C. .

Preferably, the two rollers 82 , 84 rotate at the same speed. The speed of the two rollers 82 , 84 is chosen so as to create a clogging of melted fibers 80 upstream of the two rollers 82 , 84 . This can in particular be achieved by choosing a speed of the rollers 82 , 84 such that the product of the area of the smallest surface between the two rollers 82 , 84 multiplied by the speed of rotation of the rollers 82 , 84 is less than the surface flow rate of the extrusion die 76 . According to a particular example, this can in particular be obtained by choosing a speed of rotation of the rollers 82 , 84 , lower than the speed of the curtain 78 of fibers 80 upstream of the two rollers 82 , 84 . Thus, an accumulation of melted fibers 80 forms upstream of the rollers 82 , 84 . The fibers 80 then tend to form continuous loops which, due to the temperature of the fibers 80 , weld together. In particular, the fibers 80 can fuse with each other. It is thus possible to obtain a tangle of molten fibers 80 , which is then guided between the rollers 82 , 84 to have a substantially rectangular cross section. In particular, the thickness of the tangle 86 of fibers 80 can be defined by the distance between the two rollers 82 , 84 , the thickness of the tangle 86 of fibers 80 being in particular substantially equal to the distance between the two rollers 82 , 84 . The fibers 80 may be distributed irregularly in the tangle 86 of fibers 80 , in particular according to a distribution which may appear random to an observer.

We note here that the rollers 82 , 84 deliver the tangle 86 of fibers 80 in a substantially continuous manner. In other words, the volume of fibers 80 passing through the area between the two rollers 82 , 84 is substantially constant per unit of time. In other words still, the tangle 86 of fibers 80 is continuous at the exit of the rollers 82 , 84 .

In a third step of the process, the fibers 80 are solidified. To do this, the tangle 86 of fibers 80 can be guided in a cooling bath 88 , for example a bath of cooling liquid such as water, after passing through the passage between the two rollers 82 , 84 . For example, the two rollers 82 , 84 are immersed halfway up, as illustrated in .

In a fourth step of the process, the tangle 86 of fibers 80 is guided, outside the cooling bath 88 , in particular to be dried. Drying can be carried out by shaking/vibrating the tangle 86 of fibers 80 . The tangle 86 of fibers 80 can then be shaped to form the quilting piece 44 , 46 , 48 . The tangle 86 of fibers 80 can in particular be cut, glued and/or thermoformed. As illustrated in , several layers of tangle 86 of fibers 80 can be glued together, if necessary, to obtain a satisfactory thickness of the quilting piece 44 , 46 , 48 .

In particular, one face of the tangle 86 of fibers 80 intended to be oriented towards an occupant of the vehicle seat 10 can be shaped by thermoforming. Such an operation makes it possible to reinforce the face of the tangle 86 of fibers 80 oriented towards the occupant of the vehicle seat 10 and, thus, to extend its lifespan in use.

The process which has just been described with regard to the makes it possible to obtain a substantially homogeneous piece of padding 44 , 46 , 48 , having similar fibers 80 and a homogeneous apparent density, in substantially the entire volume of the piece of padding 44 , 46 , 48 .

There illustrates how the implementation of different extrusion dies 74 A - 74 C can influence the fibers 80 and/or the tangle 86 of fibers 80 at the outlet of the process and, therefore, on the cushioning piece 44 , 46 , 48 .

Thus according to a first example, the extrusion nozzles 76 of the first extrusion die 74 A shown on the are suitable for producing fibers 80 of full section. In particular, the extrusion nozzles 76 of the first extrusion die 74 A can be circular. The fibers 80 obtained with such extrusion nozzles 76 are substantially cylindrical, of solid section.

On the contrary, the extrusion nozzles 76 of the second extrusion die 74 B of the are suitable for producing fibers 80 of hollow section. For example, the extrusion nozzles 76 of the second extrusion die 74 B take the form of two slots, not contiguous, extending along the same circle. Remarkably, for the same apparent density, a tangle 86 of solid fibers 80 is significantly more flexible than a tangle 86 of hollow fibers 80 .

The third extrusion line74 VSillustrated in includes extrusion nozzles76suitable for making fibers80full and other extrusion nozzles76, suitable for making fibers80hollow. In addition, the extrusion nozzles76suitable for making fibers80Hollows are distributed according to a different density, in two distinct zones. The third extrusion line74 VSthus makes it possible to create an entanglement86fiber80as illustrated on the presenting:
- a first layerC1fiber80hollow, with high fiber density80 ;
- a second layerC2fiber80hollow, with fiber density80weaker than in the first layerC1 ;
- a third layerC3fiber80full, such as the second layerC2is sandwiched between the first and third layersC1,C3.

The entanglement 86 of fibers 80 thus makes it possible to obtain a more rigid structure of the cushioning piece 44 , 46 , 48 in the vicinity of the seat frame 14 , by placing the first layer C1 in the vicinity of the frame d seat 14 , and a more flexible, and therefore more comfortable, structure in the vicinity of or in contact with the occupant of the vehicle seat 10 , by placing the third layer C3 there.

More generally, by locally modifying the density and type of extrusion nozzles 76 of the extrusion die 74 , it is possible to obtain an entanglement 86 of fibers 80 having fiber densities 80 and/or types fibers 80 , for example solid or hollow, different, at different locations of the tangle 86 of fibers 80 . It is thus possible to locally influence the characteristics of the cushioning piece 44 , 46 , 48 , in particular its flexibility/rigidity.

THE has illustrate a second example of a method for producing a tangle 86 of fibers 80 , which can be implemented as a quilting piece 44 , 46 , 48 of one of the filling modules 38 , 40 , 42 described previously.

According to the second example of the method illustrated, the extrusion die 74 comprises controlled extrusion nozzles 76 . It is thus possible to open or close at least some of the extrusion nozzles 76 of the extrusion die 74 during the extrusion process. The opening and closing of the extrusion nozzles 76 can be controlled by an electronic control unit 90 , in particular a computer.

In addition, the extrusion die 74 is here arranged vertically above a bath 8 8 of cooling liquid, here water, not illustrated in the figure. . A mold 92 is immersed in the bath 88 of coolant, the mold 92 being movable in the bath 88 of coolant. The movement of the mold 92 can in particular be controlled by the electronic control unit 90 . The mold 92 can in particular be moved vertically in the bath 8 8 , to control the height of the cavity 94 of the mold 92 immersed in the cooling bath 8 8 . Thus, the mold 92 is filled with the melted fibers 80 , preferably continuous, so that loops are formed between the fibers 80 . The fibers 80 , immersed in the cooling bath 8 8 , cool and harden, forming a tangle of continuous fibers, with loops welded together.

For example, on the , the extrusion begins with the generation of a curtain of fibers 80 melted into two distinct parts which fill only two hollow reliefs 96 of the cavity 94 of the mold 92 , for example for the molding of lateral tubes, and not a part central 98 of the cavity 94 of the mold 92 . It should be noted here that the shape of the cavity 94 of the mold 92 is given here for illustrative purposes only. In particular, to produce the trim piece 44 , 46 , 48 , the recessed reliefs 96 may appear unnecessary, or only a recessed relief 96 may be necessary.

There illustrates a later time of the second example of the process. In this second step, the mold 92 was moved into the bath 88 of coolant. In particular, here, the mold 92 has been lowered into the bath 8 8 of coolant. Due to the movement of the mold 92 in the bath 8 8 of cooling liquid, the melted fibers 80 , previously received in the hollow reliefs 96 , are immersed in the cooling bath and harden. A lower layer of a piece of padding 44 , 46 , 48 is thus formed.

Furthermore, as shown in the , the electronic control unit9 0controls the opening of all extrusion nozzles76, so that the melted fiber curtain80fills the entire cavity94of the mold92, namely not only the two hollow reliefs96of the cavity 94of the mold92, but also the central part98of this cavity94. In particular, part of the melted fibers80extruded at this stage covers the part of the same fibers80already received in the hollow reliefs92and hardened or in the process of hardening, in the bath8 8cooling. Thus, by moving the mold substantially continuously92in the cooling bath8 8and by controlling the opening of the extrusion nozzles in a coordinated manner76the mold can be filled continuously92fiber80, preferably continuous, forming a tangle of fibers with loops welded together. The entanglement can be substantially identical to that described with regard to the first example of the process. One or more finishing steps, including for example cutting and/or gluing and/or folding and/or thermoforming, can be carried out before obtaining the quilting piece.44,46,48ready to be placed on the trim module38,40,42partner. In particular, a step of thermoforming a surface of the quilting piece44,46,48, intended to be oriented towards an occupant of the vehicle seat can be implemented. This allows, in addition to shaping the surface, to strengthen this surface and thus extend its lifespan.

There illustrates a third example of a method for producing a cushioning piece 44 , 46 , 48 , of a trim module 38 , 40 , 42 . This third example is a variant of the first process example. The third example of a method differs from the first example of a method essentially in that at least one guide roller 82 , 84 is not cylindrical, but has at least one relief, projecting or recessed relative to a cylindrical envelope, to allow a first shaping of the tangle 86 of fibers 80 as soon as the fibers 80 pass between the two rollers 82 , 84 . For example, a roller 82 , 84 or both may include a radial groove in order to form a sausage on the tangle 86 of fibers 80 .

Thus, by adapting the surfaces of the guide rollers 82 , 84 , it is possible to produce an entanglement of fibers forming one or more sausages or, on the contrary, one or more portions of small thickness. It may thus be possible to do without a thermoforming step. Alternatively, this thermoforming step can be simpler and/or shorter, in particular, in the case where a first shaping of the tangle of fibers is obtained by using non-cylindrical guide rollers 82 , 84 . Advantageously, the step of thermoforming a surface of the tangle 86 of fibers 80 intended to be oriented towards an occupant of the vehicle seat 10 is retained, which makes it possible to densify the tangle 86 in the vicinity of this surface and, thus , to extend the lifespan of the piece of padding thus obtained.

The present invention is not limited to the examples described above. On the contrary, the invention is capable of numerous variations accessible to those skilled in the art.

Thus, in the example illustrated, each trim module 3 8 , 40 , 4 2 comprises a support and a piece of padding fixed to the support. Alternatively, a trim module 38 , 40 , 42 may be devoid of support, or even include only a piece of padding. When a upholstery module is devoid of support as described above, it may include rigid inserts, incorporated into the cushioning piece, to facilitate attachment to the backrest frame. Such inserts can be incorporated by overmolding the corresponding quilting piece onto these inserts. By “rigid”, we mean here that the inserts are notably more rigid than the rest of the quilting piece, in particular than the foam block or the tangle of fibers.

The support 5 2 of the central trim module 4 2 can also take other shapes than that described above. In particular, the support 5 2 can be a frame comprising two crosspieces, preferably rigid, and two uprights, rigid or flexible, spring elements, in particular elastic wires extending between the crosspieces and/or between the uprights. In this case, advantageously, the crosspieces are fixed to the crosspieces of the backrest frame. The uprights of the support can then be free in relation to the uprights of the backrest frame 17 . Straps can also be provided between the uprights of the support then formed and the uprights of the backrest frame 17 , particularly when the uprights are rigid. The padding part of the central trim module can then be overmolded on the support 5 2 , in particular on the crosspieces of the support 5 2 in the form of a frame. Even when the support 5 2 is not in the form of a plate as described above, one or more elements ensuring a comfort function can be fixed on the support 5 2 . These elements are in particular those described previously. This is particularly true when the support has a frame shape as described above.

Also, each trim module 3 8 , 40 , 4 2 may include a cover covering all or part of the respective quilting piece 44 , 46 , 48 . A cover can in particular be placed in the mold used for overmolding the cushioning piece 44 , 46 , 48 on the respective support 5 2 , 67 , 68 . The cover then adheres to the quilting piece 44 , 46 , 48 . Alternatively, the cover can be fixed on the quilting piece 4 4 , 4 6 , 4 8 and/or on the support 5 2 , 67 , 68 after the formation of the quilting piece 4 4 , 4 6 , 4 8 . In other words, the cover can be attached to the quilting piece 4 4 , 4 6 , 4 8 and/or to the support 5 2 , 67 , 68 . The cover is then fixed by any means accessible to those skilled in the art.

According to yet another variant, a single cover is used to cover the three pieces of padding 4 4 , 4 6 , 4 8 of the trim modules 3 8 , 40 , 4 2 . Here again, in this case, the cover is attached to the quilting pieces 4 4 , 4 6 , 4 8 and/or to the supports 5 2 , 67 , 68 respectively of the trim modules 3 8 , 40 , 4 2 , or even on the backrest frame 17 and/or the rear shell 50 . Here again, the cover is fixed by any means accessible to those skilled in the art.

Advantageously , each trim module 38 , 40 , 42 is trimmed independently of the other two, as described previously. Alternatively, however, it is possible that a piece of padding, for example, is common to several trim modules, in particular to all the trim modules 3 8 , 40 , 4 2 .

In the example described above, each trim module 38 , 40 , 42 is fixed to the backrest frame 17 independently of the other trim modules 38 , 40 , 42 . In other words, fixing means are implemented only between the backrest frame 17 , on the one hand, and each of the trim modules 38 , 40, 42 , on the other hand. Alternatively, however, each trim module 3 8 , 40 , 4 2 can be fixed on the seat frame 17 independently of the other trim modules 3 8 , 40 , 4 2 . Thus, although there are fixing means implemented between at least two trim modules 3 8 , 40 , 4 2 , in particular between the central trim module 4 2 and one or both side trim modules 3 8 , 40 , each trim module 3 8 , 40 , 4 2 comprises fixing means capable of ensuring the fixing of the trim module considered on the backrest frame 17 , independently of the other trim modules 3 8 , 40 , 4 2 .

Furthermore, the examples described above relate essentially to the production of a vehicle seat back trim. However, any trim for a vehicle seat element can be produced in a similar manner. Possibly, the numerical values may then be slightly different, in particular the thickness of the quilting pieces. For example, in the case of the upholstery of a vehicle seat base, the quilting piece(s) may have a thickness greater than or equal to 40 mm and/or less than or equal to 120 mm.

Furthermore, several methods have been described for producing padding pieces formed by an entanglement of fibers, preferably continuous, forming loops welded together. Other processes can be implemented to produce such a piece of quilting. Different processes for producing such a piece of quilting may have in common the steps consisting of:
a) extruding a material comprising at least one thermoplastic polymer in an extrusion die 74 comprising a plurality of extrusion nozzles 76 , to form a curtain 78 of molten fibers 80 ;
b) forming a tangle 86 of molten fibers 80 , preferably continuous, the fibers 80 forming loops welded together;
c) cooling the tangle 86 of fibers 80 .
These methods can then differ in the way of cooling the tangle 86 of fibers 80 and/or in the way of forming the tangle 86 of fibers 80 with loops welded together.

Finally, we have described above a seat back 16 which can be implemented in the seat 10 of the , knowing that a similar trim can be adapted to different vehicle seat elements. By “vehicle seat element”, we mean here one of:
- a seat 13 ;
- a file 16 ;
- a headrest 34 ;
- an armrest;
- a backrest top adjustment device;
- a seat length adjustment device; And
- a set of at least two aforementioned elements.
In particular, the seat element may comprise a seat 13 and a backrest 16 , the seat element preferably consisting of a seat 13 and a backrest 16 .

Claims (13)

Upholstery (15; 18) for a vehicle seat element (13; 16), comprising a first upholstery module (42) with a first cushioning piece (48) and at least one second upholstery module (38; 40) with a second cushioning piece (44; 46), the first trim module (42) and the at least one second trim module (38; 40) being adapted to be fixed to a frame (14; 17) of the element vehicle seat (13; 16), independently of each other, at least one of the first cushioning piece (48) and the at least one second cushioning piece (44; 46) comprising an interlocking (86) of fibers (80), forming loops welded together, the fibers (80) being made of a material including a thermoplastic polymer. Trim according to claim 1, in which the at least one of the first quilting piece (48) and the at least one second quilting piece (44; 46) comprising an entanglement (86) of fibers (80), forming loops welded together, the fibers (80) being made of a material including a thermoplastic polymer, have a surface intended to be oriented towards an occupant of the vehicle seat (10) shaped by thermoforming. Upholstery according to claim 1 or 2, wherein the first upholstery module (42) comprises a support (52), the first quilting piece (48) being attached to the support (52). Trim according to claim 3, in which the first trim module (42) comprises at least one device adapted to perform a comfort function for the occupant of the vehicle seat (10), the at least one device being fixed on the support (52). Upholstery according to one of claims 1 to 4, in which the at least one second upholstery module (38; 40) comprises a support (67; 68), the at least one second piece of padding (44; 46) being fixed on the support (67; 68). Trim according to any one of the preceding claims, comprising two second trim modules (38; 40), each with a respective quilting piece (44; 46), the first trim module (42) being intended to be arranged between the two second trim modules (38; 40). Trim according to any one of the preceding claims, in which each trim module (38; 40; 42) comprises a respective cover or in which a single cover is adapted to cover the different trim modules (38; 40; 42). A vehicle seat element (13; 16) comprising a vehicle seat element trim (15; 18) according to any one of the preceding claims. Vehicle seat element (13; 16) according to claim 8, wherein the vehicle seat element (13; 16) is one of:
- a seat (13);
- a file (16);
- a headrest (34);
- an armrest;
- a backrest top adjustment device;
- a seat length adjustment device; And
- a set of at least two aforementioned elements. Vehicle seat element (13; 16) according to claim 8, in which the seat element (13; 16) is a seat (13) or a backrest (16), and the trim (15; 18) of the The vehicle seat element (13; 16) comprises a first upholstery module (42) with a first cushioning piece (48) and two second upholstery modules (38; 40) each with a second cushioning piece (44; 46), the first upholstery module (42) being intended to be arranged between the two second upholstery modules (38; 40), the first padding piece (48) forming a central part of the padding of the seat element (13; 16), the two second trim modules (38; 40) forming lateral supports for an occupant of the vehicle seat. A method of manufacturing a trim for a vehicle seat element according to any one of claims 1 to 7, the method comprising the step of providing a first cushioning piece (48) and at least a second cushioning piece ( 44; 46), at least one of the first piece of padding (48) and the at least one second piece of padding (44; 46) comprising an entanglement (86) of fibers (80), forming loops welded between they, the fibers (80) being made of a material including a thermoplastic polymer. Method according to claim 11, in which the quilting piece (44; 46; 48) comprising a tangle (86) of fibers (80) forming loops welded together, the fibers (80) being made of a material including a thermoplastic polymer , is carried out by implementing the steps consisting of:
a) extruding a material comprising at least one thermoplastic polymer into an extrusion die (74) comprising a plurality of extrusion nozzles (76), to form a curtain (78) of molten fibers (80);
b) forming a tangle (86) of molten fibers (80), the fibers (80) forming loops welded together;
c) cooling the tangle (86) of fibers (80). Method according to claim 11 or 12, comprising a step of shaping by thermoforming at least one face of the tangle (86) of fibers (80) intended to be oriented towards an occupant of the vehicle seat (10).