FR3118071A1 - Patterned interior lining, in particular for a vehicle - Google Patents

Abstract

Patterned interior lining, in particular for a vehicle The process for manufacturing the coating includes supplying a sheet of fibers (20), looping the fibers, accumulating the loops formed by the looping in brushes, depositing a reinforcing sheet (38) pre- needled, on the accumulated loops, assembling the accumulated loops with the reinforcing ply (38), by needling through the brushes, in order to obtain a needled structure, removing the structure from the brushes, and shearing the accumulated loops of the structure to generate a pile. The reinforcing ply (38) includes second fibers and binder fibers, the binder fibers having a lower melting point than the second fibers. Prior to the deposition step, certain areas of the reinforcing ply are heated according to a desired pattern, to a temperature above the melting point of the binding fibers. Figure for the abstract: Figure 1

Description

Patterned interior lining, in particular for a vehicle

The present invention relates to a process for manufacturing an interior lining, in particular a floor covering for a motor vehicle.

Devices for manufacturing interior linings for motor vehicles are already known in the state of the art, comprising in particular a needling machine of the DILOUR® type.

For example, document FR 3 041 001 describes a covering manufacturing device suitable for producing a homogeneous, high-density pile.

Such a device has the particularity of comprising conveyors covered with brushes which are used to form a homogeneous pile.

More particularly, the velvet is manufactured by implementing a preliminary step of producing a sheet of fibers elongated in a longitudinal direction, in particular by lapping with interlacing of the fibers, then a step of passing the sheet of fibers along the longitudinal direction, through a looping device comprising a set of rotating discs and fixed looping elements. The curling device curls the fibers by verticalizing them, thus forming undulations, then the sheet of fibers is brought on a conveyor equipped with brushes, so that the undulations accumulate in the brushes so as to reach a predetermined density.

In accordance with this known device, the structure constituted by the undulations of densified fibers is thus temporarily blocked inside the brushes of the conveyor of a Dilour machine, that is to say by a purely mechanical trapping and therefore without it is necessary to use a glue. This document then provides for the waves to penetrate deeper inside the brushes up to the depth corresponding to the height of the pile desired for the finished product.

The present invention aims to improve a coating manufacturing process, by allowing the production of a pattern on the coating.

To this end, the subject of the invention is in particular a process for manufacturing a vehicle covering, in particular a motor vehicle floor covering, comprising:

- a step of supplying a sheet of first fibers,

- a step of looping the first fibers by means of a looping device comprising a set of rotating discs and fixed looping elements,

- a step of accumulation of the loops formed by the looping, in a conveyor equipped with brushes, arranged at the exit of the looping device,

- a step of depositing a pre-needled reinforcing ply on the loops accumulated in the brushes,

- a step of assembling the accumulated loops with the reinforcement ply, by needling through the brushes, in order to obtain a needled structure,

- a step of removing the structure from the brushes,

- a step of shearing the accumulated loops of the structure to generate a pile,

characterized in that

- the reinforcing ply comprises second fibers and binding fibers, the binding fibers having a melting point lower than that of the second fibers,

- the method comprises, prior to the deposition step, a step of heating certain areas of the reinforcing ply, according to a desired pattern, to a temperature above the melting point of the binding fibers.

In the zones heated to a temperature above the melting point of the binding fibers, the fibers are joined together by the material derived from the binding fibers. Thus, during the assembly step, the fibers of these areas are not dragged by the needling needles.

As a result, the assembly is not carried out in these areas.

When removing the structure from the brushes, the first fibers facing these areas, which have not been assembled to the reinforcement ply, remain trapped in the brushes.

The coating thus has zones without first fibers (corresponding, as indicated above, to zones of the reinforcing ply which have been heated to a temperature above the melting point of the binding fibers), and zones comprising the first fibers , which will form a pile. The areas without first fibers form a pattern, which is the pattern formed by the heated areas.

A coating having one or more patterns has thus been produced in a simple and effective manner.

A manufacturing method according to the invention may also comprise one or more of the following characteristics, taken alone or in any technically conceivable combination.

- The heating step is carried out by calendering the reinforcing ply, by means of at least one heating roller having a protruding pattern.

- The heating step is carried out by applying a heating plate with a protruding pattern.

- The first fibers are of a different nature from the second fibers, and have for example a different titer, a different shine, and/or are made of different materials.

- The first fibers have a different color from that of the second fibers.

- The second fibers are chosen fine, with a count of less than 11 Dtex, preferably around 6.7 Dtex.

- The method comprises a prior step of orienting the first fibers with respect to a longitudinal direction of advance, such that, the looping step being configured to generate undulations formed by loops each having a predefined width G in a direction perpendicular to the longitudinal direction, and a predefined height H in an elevation direction perpendicular to the transverse direction and to the longitudinal direction, the orientation step is configured to orient the fibers parallel to a general direction forming an angle α with the longitudinal direction, given by the relation sinα=G/2H to within +/- 5°.

- The binding fibers are of the two-component type, comprising a core of a first material and a sheath of a second material, such that the sheath has a melting temperature lower than that of the core, and lower than that of the second fibres.

The invention also relates to a device for manufacturing a vehicle covering, in particular a motor vehicle floor covering, for carrying out the method as defined above, the manufacturing device comprising:

- a looping device for the first fibers of a layer of fibers, comprising a set of rotating discs and fixed looping elements,

- a conveyor equipped with brushes, arranged at the exit of the looping device, for the accumulation of loops of the layer of fibers in the brushes,

- a device for depositing a pre-needled reinforcing ply on the loops accumulated in the brushes,

- a device for assembling the accumulated loops with the reinforcement ply, by needling through the brushes, in order to obtain a needled structure,

- a device for shearing the accumulated loops of the structure to generate a pile,

characterized in that it comprises a device for preparing the reinforcing ply, comprising:

- a device for producing a pre-ply comprising second fibers and binding fibers, the binding fibers having a melting point lower than that of the second fibers,

- a device for needling the pre-ply to form the reinforcing ply, and

- A device for heating certain areas of the reinforcing ply, according to a desired pattern, to a temperature above the melting point of the connecting fibers.

The invention finally relates to a coating, in particular an interior coating of a motor vehicle, produced by means of the manufacturing process as defined above.

Various aspects and advantages of the invention will be highlighted on reading the following description, given solely by way of non-limiting example and made with reference to the appended figures, among which:

- There schematically represents a device for manufacturing a coating making it possible to carry out the manufacturing method according to an exemplary embodiment of the invention;

- There is a partial cross-sectional view of a liner fabricated by the device for fabricating the ;

- There is a top view of a fiber web as it is inserted into the fabric making device ;

- There is a top view of part of the device for manufacturing the ,

- There schematically represents a device for manufacturing a reinforcing ply used for manufacturing the coating.

We have represented, on the , a device 10 for manufacturing a coating 12.

The coating 12, manufactured according to the method of the invention, is shown in more detail, in section, on the . This covering 12 forms for example an interior covering, and more particularly an interior covering of a motor vehicle, intended to be placed on the ground or on a wall of the vehicle. Alternatively, liner 12 may form any conceivable interior liner.

The coating 12 has a face layer 14 of unbonded fibers parallel to each other, and a back layer 16 forming a sole formed essentially of fibers bonded together.

Face layer 14 has a velvety outer appearance. This pile is made up of the fibers in the form of sheared loops and free fibers, as will be described later in more detail.

The thickness of the face layer 14 is generally greater than that of the sole 16. The face layer 14 has for example a thickness of between 2 and 8 mm.

The pile density in the face layer 14 is preferably between 0.05 and 0.12 g/cm3, for example between 0.07 and 0.08 g/cm3. Such a density ensures a good appearance, good resistance to abrasion and ease of cleaning.

This density is measured for example by determining the ratio between the mass of the material obtained by shaving the entire face layer 14 up to the sole 16, relative to the initial volume of the shaved layer.

The yield of the pile, consisting of the ratio of the weight of pile after total shaving up to the sole relative to the total weight of the part 12, is for example between 50 and 80%.

The manufacturing device 10 comprises a carding and lapping device 18 (known as a crosslapper) with interlacing fibers, suitable for producing a web 20 of first fibers 15.

The length of the first fibers 15 used is generally between 40 and 150 mm.

The title of the first fibers 15 is preferably between 4 and 17 dtex.

The crimp of the first fibers 15 is preferably between 2.5 and 4 undulations per cm.

The carding operation is carried out in a conventional manner and makes it possible to obtain a veil with a surface weight of between 40 and 160 g/m². Such a web is formed by first individualized fibers 15 mostly oriented in a longitudinal direction, corresponding to a production direction (machine direction). Nevertheless, these first fibers 15 overlapping slightly due to their crimp, it is accepted that the average angle with respect to the longitudinal direction of this type of veil is between 5 and 10° (We resonate here by positioning ourselves in a half plane with respect to the axis of the longitudinal direction, because the first fibers 15 are positioned symmetrically with respect to this axis). In the following and to facilitate the description, we will assume that this value, unless otherwise specified, is close to 0°.

The first fibers 15 are for example made from a thermoplastic polymer, such as polypropylene, polyethylene terephthalate (PET), polyamide, polylactic acid, their mixtures or their copolymers. As a variant, the first fibers can be fibers of natural origin such as flax or hemp fibers used alone or in mixtures.

According to a possible embodiment, the first fibers have a first color. More particularly, all the first fibers forming the web 20 have the same first color, possibly with slight nuances.

The topping device 18 is of the conventional type, and will therefore not be described in more detail. The particularity of the use of this device in the context of the invention is that only one ply is made, so that the first fibers 15 intersected by the crosslapper extend parallel to a direction forming an average angle β of about 60° with the longitudinal direction X, obviously in the case where the layup width corresponds to the carding width.

The sheet 20 at this stage of the process therefore consists of two superposed webs having their first fibers 15 mainly oriented with an average angle β of 60° symmetrically with respect to the longitudinal axis X materializing the machine direction.

The manufacturing device 10 preferably comprises, following the laying device 18, a device 22 for orienting the first fibers 15 of the layer of fibers 20. This orientation device 22 can be placed at the outlet of the laying device 18, or alternatively be disposed at a distance, in which case the sheet of fibers 20 is moved from the lapping device 18 towards the orientation device 22.

The orientation device 22 is capable of modifying the orientation of the first fibers 15, initially oriented with the mean entry angle β, to parallelize them to a general direction A, B forming a predetermined mean angle α with the longitudinal direction X. The first fibers 15 being intersected, some are aligned parallel to a first general direction A forming an angle α with the longitudinal direction X in a clockwise direction, and others are aligned parallel to a second general direction B forming an angle α with the longitudinal direction X in a counterclockwise direction.

The orientation device 22, shown in more detail in , is for example a device for drawing the web of fibers 20, the first fibers 15 of which are criss-crossed. This stretching device 22 comprising a first set 24 of upstream drive rolls, and a second set 26 of downstream drive rolls. Each set 24, 26 comprises two complementary cylinders between which the sheet 20 passes, in contact with these two cylinders. The rotational drive of the cylinders of each assembly 24, 26 therefore allows the sheet 20 to be driven along the longitudinal direction X.

This device 22 is strictly speaking an orientation device and not a stretching device, although the web 20 sees its surface mass reduced between the two sets of cylinders, because its role is to rotate the first fibers 15 relative to each other (their point of intersection serving as a pivot point) and not to stretch the web by causing the fibers to slide parallel to each other as in a conventional textile stretching device. As a result, the aim is to position the two sets of cylinders as close as possible. Thus if L is the length of the first fiber 15, the distance between the pinch lines of the two sets of cylinders will be slightly greater than L.cos β.

However, later on, we can speak of stretching and stretched web in reference to this variation in surface mass of the web.

The downstream drive cylinders of the second set 26 are rotatable with a rotational speed greater than that of the upstream drive cylinders of the first set 24, so that the sheet of fibers 20 is not driven with the same speed. over its entire length. This web of fibers 20, passing between the cylinders of each assembly 24, 26, is then stretched due to this difference in speed.

This stretching makes it possible to align the first fibers 15 of the web 20 parallel to the desired general directions A and B.

We will note Ve the peripheral speed of the inlet cylinders and Pe the surface mass of the sheet engaging between the inlet cylinders, Vs the peripheral speed of the outlet cylinders and Ps the surface mass of the sheet engaging between the input cylinders. We will note α the average angle of the fibers with respect to the longitudinal direction X of the outlet sheet.

We have the following relationship: E (stretching)=Ve/Vs=Pe/Ps=cosα/cosβ.

Thus, the value of E can be determined as a function of the desired angle α and the angle β which depends on the width of the web at the card outlet and the width of the topping.

We have tan β = 2 Ln/Lv,

with Ln topping width and Lv veil width.

So if Lv = Ln (for example in the case of a 2.5m wide card for a 2.5m topping corresponding to the width of the finished product) which will generally be the case, β≈60°.

If, for example, the desired value of α is 20°, we will therefore have E=cos 20° /cos 60°= 1.8

We have described a stretching device consisting of two sets of cylinders but this stretching could be carried out by different means. For example, it could take place between the end of the tablecloth supply belt and the discs of the device 130.

The manufacturing device 10 comprises, at the output of the orientation device 22, a looping device 28. Such a looping device 28 is intended to loop the first fibers 15 of the sheet 20 by verticalizing them, thus forming undulations.

This looping device 28 comprises a set of rotating discs 30 carried on a common transverse axis, driven in continuous rotation at a peripheral speed preferably equal to the entry speed of the veil 20 into this looping device 28.

The rotating discs 30 are each preferably provided on its periphery with a toothing enabling the web of fibers 20 to be driven. For example, the uprights of two adjacent teeth form an angle D greater than 100°, in particular approximately 103° .

The looping device 28 also comprises looping elements, in particular looping fingers 32, each being arranged between two adjacent discs 30 . The looper fingers 32 extend to one end which is substantially tangential to the discs 30. Thus, each first fiber 15 is pre-looped by being driven at each end by a respective disc 30, overcoming the looper finger 32 corresponding disposed between these two discs 30.

The routing of a first fiber 15 between two adjacent discs 30 will now be described.

The first fiber 15 has an angle α with the longitudinal direction X, which is also the direction of advance of the web 20 in the looping device 28.

A front part of the first fiber 15 is driven by one of the discs 30, and a rear part of this first fiber 15 is driven by the other disc 30. These two discs being fixed to the same axis, their speeds of rotation are identical.

The front part of the first fiber 15 arrives first at the end of its travel, against an abutment which will be described later. While the front part is in abutment, the rear part continues to advance until it also comes into abutment, thus bending the first fiber 15 which then forms a loop.

The first fibers 15 passing through the looping device 28 all have the same behavior as described above, so that all of the first looped fibers 15 form undulations over the width of the web 20, taken in a transverse direction. perpendicular to the longitudinal direction X.

Each loop has a height H, taken in an elevation direction perpendicular to the longitudinal direction and to the transverse direction, and a width G taken in the transverse direction. It should be noted that the width G corresponds substantially to the interval between two adjacent discs 30.

The discs 30 are positioned in such a way that they penetrate from a depth P≤H inside the brushes of a band 33 of the same type as the brushes equipping the conveyor of a Dilour® machine. At the location of the discs, the bristles making up the brushes are flexible enough to move apart and gather in the free space between the discs.

This type of band serves as a stopper as mentioned above. Indeed, when they are no longer in the presence of the discs, the brush bristles, by returning to their initial position, exert pressure on the fibers which makes it possible to block and then maintain the structure of the undulations.

The abutment mentioned above is therefore formed by a belt 33 of a conveyor 34. The belt 33 is an endless belt, extending between two drive cylinders. Strip 33 is provided with brushes.

The strip 33 is moved, in the longitudinal direction X, with a speed lower than the tangential speed of the rotating discs 30, so that they have the effect of a stop for the fibers 15 coming out of these rotating discs 30.

The undulations then accumulate on the brushes of the strip 33, with a density depending on the difference in speed between the rotating discs 30 and the strip 33. Those skilled in the art will be able to determine this difference in speed as a function of the density desired.

For example, if the desired surface mass of the pile is 300 g/m² and if the ply after stretching has a surface mass of 50 g/m², the speed ratio between the conveyor and the peripheral speed of the discs will be 300/50=6. This high ratio guarantees operation according to the “stop” logic.

This device makes it possible to obtain a high density of velvet, which is generally not achievable by conventional methods.

The brushes also prevent the first fibers 15 from being drawn upwards by the discs 30, which would harm the formation of the waves.

The manufacturing device 10 then comprises a device 36 for depositing a reinforcing ply 38 on the corrugations accumulated on the brushes. The reinforcing ply 38 is formed by second fibers 17 mixed with binding fibers.

According to a possible embodiment, the second fibers 17 have a second color different from the first color. All the second fibers 17 have the same second color, possibly with a few slight nuances.

The second fibers 17 are for example made from a thermoplastic polymer, such as polypropylene, polyethylene terephthalate (PET), polyamide, polylactic acid, their mixtures or their copolymers. As a variant, the second fibers 17 can be fibers of natural origin such as flax or hemp fibers used alone or in mixtures.

The second fibers 17 are for example of the same nature as the first fibers 15.

However, in a variant, the second fibers 17 are of a different nature from that of the first fibers 15. The first 15 and second 17 fibers have for example a different fineness, a different shine, and/or are made of different materials. For example, the first fibers 15 can be based on polyamide while the second fibers 17 will be based on PET.

Advantageously, the second fibers 17 are fine, for example with a denier of less than 11 Dtex, for example with a denier equal to 6.7 Dtex.

As indicated above, the reinforcing ply 38 comprises a percentage of binder fibers, that is to say, for example, bi-component fibers of which one of the components has a lower melting temperature than the other. For example, the two-component fibers comprise a core of the same nature as the second fibers 17, and a sheath of bonding material.

In all cases, the binding fibers comprise (or alternatively consist of) a binding material whose melting temperature is lower than that of the second fibers 17.

The reinforcement ply 38 is prepared upstream in a preparation device 50, which will be described with reference to the .

The preparation device 50 comprises a device 52 for supplying a pre-ply 54 formed from a mixture of second fibers 17 and binding fibers.

The preparation device 50 also includes a second device 56 for needling the pre-ply 54 of second fibers. The second needling device 56 comprises for example hook needles which, penetrating the pre-ply 54 of second fibers, entangles the fibers constituting it, thus binding the second fibers 17 together and thus reinforcing the structure of the pre-ply. - ply of fibers 54 which thus becomes the reinforcing ply 38.

In accordance with the invention, the preparation device 50 comprises a device 58 for heating the reinforcing ply 38 in certain zones Z1, according to a desired pattern.

In other words, only certain zones Z1 of the reinforcing ply 38 are heated, these zones Z1 forming a pattern.

The heating is carried out at a temperature above the melting point of the binding fibers (or of the fusible part of the binding fibers, in the case of bicomponent fibers).

Thus, in the heated zones Z1, the second fibers 17 are secured together by the material from the connecting fibers.

According to an exemplary embodiment, the heating device 58 is a calendering device. In this case, the calendering device comprises at least one heating roller intended to be applied against the reinforcing ply 38, preferably at least two rollers between which the reinforcing ply 38 is intended to pass.

At least one of the rollers has a protruding pattern, this protruding pattern being heated so as to heat the reinforcing ply 38 where this protruding pattern is applied. The heated zones Z1 then correspond to this projecting pattern.

According to a variant, the heating device 58 may comprise at least one heating plate, also having a projecting pattern. The heating plate is then applied against the reinforcing ply 38, so that the heated zones Z1 correspond to this projecting pattern.

The preparation device 50 finally comprises a device 60 for rolling up the reinforcing ply 38, with a view to bringing it back in the form of a roll in the manufacturing device 10.

The reinforcement ply 38 thus prepared is thus deposited, by the deposition device 36, on the corrugations accumulated on the brushes.

The structure formed by stacking the first corrugated fibers 15 and this reinforcing ply 38 is then intended to pass under a needling device 40 or needling head, comprising at least one needle board 41.

The assembly formed by the brush conveyor 34 and the needle boards is known per se, and for example formed by a machine of the Dilour® type.

The needle board 41 is arranged opposite the strip 33 of the conveyor 34, and it can be deployed vertically towards this strip 33 to pierce said structure.

The needle board 41 carries a plurality of needles, allowing a needling density of the order of 200 to 400 cps/cm².

The implantation of the needles complies with the Dilour® process and leads to homogeneous needling. Thus, this implantation can be arbitrary (known as “random” type) without in any way favoring a particular lineage.

This board of needles 41 makes it possible to secure the reinforcing ply 38 to the structure made up of the undulations, that is to say the ply 20 deposited totally or partially inside the brushes, by extracting second fibers 17 from the ply 38 and causing them to penetrate into the sheet 20.

The needling device is configured so that the depth of penetration of the second fibers 17 of the reinforcing ply 38 into the ply 20 is less than or equal to H. This height depends on the type of needles fitted to the needling head of the Dilour® machine, and the nature of the reinforcement ply 38.

During this needling, the face layer 14 is formed, as well as the sole 16, by intermingling the first fibers 15 with the second fibers 17 of the reinforcing ply 38.

During needling, part of the second fibers 17 of the reinforcement ply is drawn between the first fibers 15 of the loops. Indeed, the needles strike the product from above, on the side of the reinforcement ply 38. These needles first encounter the reinforcement ply 38, and cause a few second fibers 17.

However, in the heated zones Z1 of the reinforcing ply 38, the second fibers 17 are secured together, and are therefore not driven by the needles.

As a result, the assembly between the face layer 14 and the sole 16 is not made in these areas.

Thus, when the structure is removed from the brushes, the first fibers 15 facing these areas, which have not been assembled to the reinforcing ply 38, remain trapped in the brushes.

The coating thus has first zones without first fibers (corresponding, as indicated above, to zones Z1 of the reinforcing ply which have been heated to a temperature above the melting point of the binding fibers), and second zones comprising the first fibers, which will form a pile. The areas without first fibers form a pattern, which is the pattern formed by the heated areas Z1.

It will be noted that, when the first 15 and second 17 fibers have different colors, the difference between the first and second zones is even more marked.

The manufacturing device 10 then comprises a device 42 for bonding the fibers of the face layer 14 in the sole 16. This bonding device 42 is for example a heat-setting device, in particular a through-air oven or an infrared oven. .

During heating, the binding fibers of the reinforcing ply 38 are brought to their melting temperature. It will be noted that, as a variant, the sheet of fibers 20 could also comprise binding fibers.

It should however be noted that the binder fibers of the sheet of fibers 20 advantageously have the first color (with possible slight shades), and the binder fibers of the reinforcing sheet 38 advantageously have the second color (with possible slight nuances). slight nuances near).

This binding, necessary for all constructions of the needle-punched type to ensure sufficient cohesion of the fibers of the pile with the sole and to avoid problems of tearing or abrasion, is carried out in a conventional manner and will therefore not be described in more detail.

The device 10 then comprises a device 44 for shearing the top of the accumulated undulations of the structure, thus forming a pile of vertical fibers. Due to the verticalization of the corrugations in the looping device 28 and the perfect parallelism of the fibers resulting therefrom, the sheared fibers all have the same height, so that the appearance of the pile is optimized. It should be noted that the scraps of shorn fibers can be subsequently recycled.

Finally, the device 10 comprises a device 46 for rolling up the coating 12 formed, with a view to handling it.

It should be noted that, so that the pile has an optimal appearance, in particular an optimal density, and that it does not have prematurely broken fibers in the looping discs, which would harm its general appearance, the angle α of orientation of the fibers must respect the relation sinα=G/2H to within +/- 5°. The orientation of the fibers according to this angle α is implemented by the parameter setting of the orientation device 22.

The device according to the invention makes it possible to carry out a process for manufacturing a coating, which will now be described.

The manufacturing process comprises a step of producing a web and then the web of first fibers 20 having only one ply, by lapping with interlacing of the fibers. It will be recalled here that the first fibers 15 are for example chosen with a first color.

The manufacturing method then includes a step of orienting the first fibers 15 parallel to the first A or the second B general direction, each forming an angle α (clockwise or counterclockwise respectively) with the longitudinal direction X. This orientation step is carried out by means of the orientation device 22, configured so that the angle α responds to the relation sinα=G/2H, to within +/- 5°, G and H being predetermined, as indicated previously.

The method then comprises a step of passing the web of fibers 20, along the longitudinal direction X, through the looping device 28, so as to generate undulations having a predefined length G in the transverse direction, and heights H predefined in elevation direction.

The manufacturing process then includes a step of bringing the sheet of fibers 20 onto the conveyor 34 equipped with brushes, and of accumulating the undulations in the brushes so as to reach a predetermined density. The conveyor 34 is arranged at the outlet of the discs 30, so that this feed step is carried out by the discs 30. The discs penetrate the brushes to a depth P equal to the corresponding height H.

As mentioned earlier, the ripple density depends on the difference in speeds between the discs 30 and the belt 33.

It should be noted that the corrugated fibers thus accumulated are perfectly parallelized between them, so that the appearance of the coating 12 produced is optimal.

The method also includes, upstream, the preparation of the reinforcing ply 38 by means of the preparation device 50.

The pre-ply 54 is formed from a mixture of second fibers 17 and binding fibers, then it is pre-needled in the second needling device 56 to form the reinforcing ply 38.

The reinforcing ply 38 is then heated in certain areas by the heater 58, in a desired pattern.

The heating is carried out at a temperature above the melting point of the binding fibers (or of the fusible part of the binding fibers, in the case of bicomponent fibers).

Thus, in the heated zones Z1, the second fibers 17 are joined together by the material from the connecting fibers.

The reinforcement ply 38 is then rolled up in the winding device 60, to then be brought back into the deposition device 36.

The method then includes a step of depositing the reinforcing ply 38 on the accumulated corrugations. This reinforcement ply 38 is intended to form at least in part the sole 16. It will be recalled here that the reinforcement ply 38 is preferably formed of second fibers 17 having a second color different from the first color of the first fibers 15.

The method then includes a step of needling the sheet of fibers 20 through the brushes of the strip 33, to form the structure comprising the face layer 14 and the sole 16, in accordance with a conventional needling process. As indicated above, this needling is performed by a single needling head. It should be noted that the needling head is preferably fitted with “crown” type needles, that is to say needles having only one barb per edge located at the same distance from the tip. This type of needle is compatible with the use of brushes and allows effective interpenetration of the fibers of the web 38 in the web 20.

As indicated previously, during needling, the second fibers 17 of the preheated zones Z1, secured to one another, are not drawn in, so that only the second fibers 17 which are not in these previously heated zones Z1 are drawn into the first fibers 15 and linked with them.

Thanks to the needling step, the coating produced by the process according to the invention is thermoformable, therefore entirely suitable for the production of motor vehicle floor coverings.

The method then includes a step of removing the structure thus formed from the conveyor 34.

During this step, the first unbonded fibers 15 (first zones) remain trapped in the brushes, so that the structure no longer comprises first fibers 15 in the first zones.

In these first zones, only the second fibers 17 are visible, hence the formation of patterns on the face layer 14.

The method then includes cleaning the brushes, to extract the first fibers 15 which had remained imprisoned therein. These fibers can be easily recycled, by reinjecting them upstream of the device 10.

The method then includes a step of blocking or bonding the fibers of the face layer 14 in the sole 16. This blocking step is carried out in the blocking device 42, by any conceivable means.

The method then includes a step of mowing the top of the accumulated undulations of the structure. The first fibers thus sheared form a pile.

The method finally comprises a step of rolling up the coating 12 thus formed, with a view to handling it.

It will be noted that the invention is not limited to the embodiments described above, and could present various variants.

In particular, the applications of this type of coating can extend to sectors other than the automotive industry, such as housing or rail transport, even in cases where formability is not required.

Claims (10)

Method of manufacturing a vehicle covering (10), in particular a motor vehicle floor covering, comprising:
- a step of supplying a web (20) of first fibers (15),
- a step of looping the first fibers (15) by means of a looping device (28) comprising a set of rotating discs (30) and fixed looping elements (32),
- a step of accumulating the loops formed by the looping, in a conveyor (34) equipped with brushes, arranged at the output of the looping device (28),
- a step of depositing a pre-needled reinforcing ply (38) on the loops accumulated in the brushes,
- a step of assembling the accumulated loops with the reinforcing ply (38), by needling through the brushes, in order to obtain a needled structure,
- a step of removing the structure from the brushes,
- a step of shearing the accumulated loops of the structure to generate a pile,
characterized in that
- the reinforcing ply (38) comprises second fibers (17) and binding fibers, the binding fibers having a melting point lower than that of the second fibers (17),
- the method comprises, prior to the deposition step, a step of heating certain zones (Z1) of the reinforcing ply (38), according to a desired pattern, to a temperature above the melting point of the connecting fibers. Manufacturing process according to claim 1, in which the heating step is carried out by calendering the reinforcing ply (38), by means of at least one heating roller having a raised pattern. A manufacturing method according to claim 1, wherein the heating step is carried out by the application of a heating plate having a raised pattern. Manufacturing process according to any one of the preceding claims, in which the first fibers (15) are of a different nature from the second fibers (17), and have for example a different fineness, a different shine, and/or are produced in different materials. A method of manufacture according to any preceding claim, wherein the first fibers (15) have a color different from that of the second fibers (17). Manufacturing process according to any one of the preceding claims, in which the second fibers (17) are chosen to be fine, with a fineness of less than 11 Dtex, preferably approximately 6.7 Dtex. Manufacturing process according to any one of the preceding claims, comprising a prior step of orienting the first fibers (15) with respect to a longitudinal direction (X) of advance, such that, the looping step being configured to generate undulations formed by loops each having a predefined width G in a transverse direction perpendicular to the longitudinal direction, and a predefined height H in an elevation direction perpendicular to the transverse direction and to the longitudinal direction, the orientation step is configured to orient the fibers parallel to a general direction forming an angle α with the longitudinal direction (X), given by the relation sinα=G/2H to within +/- 5°. Manufacturing process according to any one of the preceding claims, in which the binding fibers are of the two-component type, comprising a core made of a first material and a sheath made of a second material, such that the sheath has a melting temperature lower than that of the core, and lower than that of the second fibres. Device (10) for manufacturing a vehicle covering, in particular a motor vehicle floor covering, for carrying out the method according to any one of the preceding claims, the manufacturing device (10) comprising:
- a device (28) for looping the first fibers (15) of a sheet of fibers (20), comprising a set of rotating discs (30) and fixed looping elements (32),
- a conveyor (34) equipped with brushes, arranged at the outlet of the looping device (28), for the accumulation of loops of the web of fibers (20) in the brushes,
- a device (36) for depositing a pre-needled reinforcing ply (38) on the loops accumulated in the brushes,
- a device (40) for assembling the accumulated loops with the reinforcing ply (38), by needling through the brushes, in order to obtain a needled structure,
- a device (44) for shearing the accumulated loops of the structure to generate a pile,
characterized in that it comprises a device (50) for preparing the reinforcing ply, comprising:
- a device (52) for producing a pre-ply comprising second fibers and binding fibers, the binding fibers having a melting point lower than that of the second fibers,
- a device (56) for needling the pre-ply to form the reinforcing ply (38), and
- a device (58) for heating certain areas (Z1) of the reinforcing ply (38), according to a desired pattern, to a temperature above the melting point of the connecting fibers. Lining (12), in particular motor vehicle interior lining, produced by means of the manufacturing process according to any one of Claims 1 to 8.