Method for producing vehicle seat facing material

Abstract

The invention relates to a method for producing a facing material (49) for a vehicle seat element, comprising the following steps: A. arranging a cover (40) in a mould (M) in such a way that the cover (40) covers at least part of the mould (M), B. overmolding a cushion (41) over the cover (40), the invention relates to a method for producing a facing material (49), comprising the following steps: A. A method for producing a facing material (49) from a cover (40) comprising a liner (41) comprising irregularly arranged 3D entangles of continuous thermoplastic fibers (52) forming a ring (43) welded together, said liner (41) being in the molten state, C. The liner (41) is solidified by cooling using a liquid (E) or a gas in order to securely connect the cover (40) to the liner, thereby obtaining the facing material (49).

Description

Technical Field

[0001] The present description relates to a method for producing a vehicle seat trim, in particular but not exclusively for producing an automobile trim, and to a method for producing a vehicle seat element using the produced trim, and also to a vehicle seat element produced by this method. Background Art

[0002] Cushions for vehicle seat elements, in particular for motor vehicle seat elements, are usually made from foams of urethane (or polyurethane, PU) polymers, in particular polyurethane foams obtained from polyols of the polyether / polyol (or PUR) type. Such foams can be shaped in a relatively easy manner in a mold to form cushions of various shapes for different vehicle seat elements, such as seat cushions or backrests.

[0003] Foam padding is satisfactory, but can retain moisture, particularly in wet conditions, which can cause discomfort to an occupant of a vehicle seat having a component that includes such padding.

[0004] Additionally, polyurethane foam is typically made by mixing polyols with isocyanates. The chemical reaction used to form the foam releases CO2, which contributes to global warming.

[0005] Furthermore, polyurethane foam is not recyclable.

[0006] Therefore, there seems to be a need to limit the use of polyurethanes in the padding of vehicle seat elements.

[0007] Additionally, vehicle seats include at least a frame, a cushion, and a cover, which are assembled together during assembly. It would be desirable to reduce the number of steps required to assemble a seat. Summary of the invention

[0008] The present disclosure improves this situation.

[0009] For this purpose, a method for producing a trim for a vehicle seat element is described, the method comprising the following steps:

[0010] A. placing a cover in the mold so that the cover covers at least a portion of the mold,

[0011] B. overmolding a liner on the cover, the liner comprising a 3D entanglement of irregularly arranged continuous thermoplastic fibers forming loops fused together, the liner being in a molten state,

[0012] C. Solidifying the liner by cooling with a liquid or gas, thereby joining the cover and the liner together to obtain the decoration.

[0013] Thus, the cushion is made of a material other than polyurethane foam. Advantageously, this cushion material is a recyclable plastic material whose manufacture produces fewer CO2 emissions than the manufacture of polyurethane foam. Additionally, the method of using this material for the cushion can produce a cushion that is significantly lighter than a similar cushion made of polyurethane foam. Additionally, the cushion material may be more breathable, allowing air and any moisture to pass through the cushion better.

[0014] Furthermore, this method enables the manufacture of trim, including covers and pads, by overmolding, which can simplify seat assembly.

[0015] The decoration comprises a cover and a liner fixed to each other.

[0016] The features disclosed in the following paragraphs can optionally be implemented independently of each other or in combination with each other.

[0017] Preferably, the cover is held by suction on its portion positioned on the mould, in particular throughout steps A, B and C. A strong vacuum is created in the mould, which holds the cover on the mould wall.

[0018] For example, the cover is made of a material selected from the group consisting of: woven material, non-woven material, leather, artificial leather and imitation leather.

[0019] The mould may take the form of a hollow shell, the walls of which, once mounted on the seat frame, reproduce the 3D configuration of the trim in the portion visible to the user.

[0020] Step B may include the following sub-steps:

[0021] i. extruding a material comprising at least one thermoplastic polymer into an extrusion die comprising a plurality of extrusion nozzles to form a molten fiber curtain,

[0022] ii. forming a molten fiber entanglement, wherein the fibers form loops that are fused together,

[0023] Step C is advantageously carried out simultaneously with step B, wherein curing takes place while the fibres are placed on the cover.

[0024] Step C can be performed by immersion in a cooling tank containing a liquid, in particular water. The initial temperature of the liquid is preferably between 8° C. and 10° C. In one embodiment, the mould is movable relative to the cooling tank.

[0025] A step of cutting the entanglement of fibers may be provided, particularly when the number of fibers is sufficient to form a mat.

[0026] Preferably, the inter-fiber spaces in the 3D fiber entanglement of the pad are free.

[0027] According to one embodiment of the method, the extrusion die used in sub-step i comprises several separate regions along its longitudinal direction, wherein the regions comprise nozzles with different surface densities, including at least one first region having nozzles with low surface density and at least one second region having nozzles with high surface density, so as to obtain at least a first region having a low packing density and at least a second region having a high packing density in the direction in which the 3D fiber entanglement extends along the longitudinal direction of the extrusion die.

[0028] According to one embodiment, which may optionally be combined with the previous embodiment, the extrusion die comprises, along its transverse direction, a first section provided with first extrusion nozzles for producing hollow fibers, and a second section provided with second extrusion nozzles for producing solid fibers.

[0029] According to one embodiment, the temperature of the extrusion carried out in the extrusion die in sub-step i is between 180°C and 240°C.

[0030] The thermoplastic fibers of the mat may be hollow fibers and / or solid fibers, with a diameter between 0.2 mm and 2 mm, preferably between 0.3 mm and 1.5 mm. The composition of the fibers preferably comprises at least 95% PET by weight. The thermoplastic material constituting the fibers may be recycled.

[0031] Sub-step ii may comprise forming said entanglement of molten fibers on the cover by forming a fiber coagulation upstream of two counter-rotating guide members and guiding a curtain of molten fibers between the two guide members, said fibers forming an annulus fused together.

[0032] The method may also comprise a step D consisting in thermoforming the liner after steps A, B and C have been carried out, in particular by applying a thermoforming tool and heat, in particular hot air, to the outer face of the liner, said outer face being on the side opposite to the inner face of the liner contacting the cover.

[0033] In one embodiment, the mold has a hollow shape with a bottom portion and at least two side portions extending from the bottom. In this case, the cover covers all or part of the bottom and side sections, and during overmolding, the bottom and sides of the cushion are defined by the cover placed on the mold. In addition, in this case, when thermoforming is performed, the purpose is to shape the cushion portion that is not in contact with the cover and that may correspond to the upper outside of the cushion in the mold.

[0034] Advantageously, the method comprises a demoulding step E.

[0035] Where appropriate, after thermoforming, before or after demoulding, for example preferably after demoulding, the process may comprise a drying step, which may be brief.

[0036] The vehicle seat element may consist of at least one of the following:

[0037] - backrest,

[0038] - Seat cushions;

[0039] -armrest;

[0040] - Headrest;

[0041] - upper backrest adjustment; and

[0042] -Device for adjusting the length of the seat cushion.

[0043] In particular, the vehicle seat element may be a seat consisting of a seat back and a seat bottom.

[0044] According to one embodiment, the thickness of the padding may be between 30 mm and 60 mm when the seat element is a backrest and / or the thickness of the padding may be between 40 mm and 120 mm when the seat element is a seat cushion.

[0045] According to one embodiment, when the seat element is a backrest, the cushioning layer may include different areas with different packing densities distributed along the longitudinal direction of the cushioning layer, when the seat element is a backrest, and / or when the seat element is a seat cushion, along the longitudinal direction of the cushioning layer, the cushioning layer may include different areas with different packing densities.

[0046] For example, the 3D entanglement of the pad has a 3 and 65kg / m 3 The packing density between.

[0047] According to another aspect, a method for producing a vehicle seat element is proposed, the method comprising the steps consisting of:

[0048] -Providing a vehicle seat element frame;

[0049] - manufacturing a trim for a vehicle seat element by implementing all combinations of the above methods; and

[0050] - Attaching the trim to the vehicle seat element.

[0051] According to a further aspect, a vehicle seat element is proposed which is produced by carrying out all combinations of the methods for producing a seat element defined above. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Other features, details and advantages will become apparent upon reading the following detailed description and analyzing the accompanying drawings, in which:

[0053] Figure 1 A side view of an example of a vehicle seat is schematically shown.

[0054] Figure 2 A schematic cross-sectional view showing a step of an exemplary method according to the present invention.

[0055] Figure 3 A schematic cross-sectional view showing a step of an exemplary method according to the present invention.

[0056] Figure 4 A schematic cross-sectional view showing a step of an exemplary method according to the present invention.

[0057] Figure 5 A schematic cross-sectional view showing a step of an exemplary method according to the present invention.

[0058] Figure 6 A schematic cross-sectional view showing a step of an exemplary method according to the present invention.

[0059] Figure 7 A schematic cross-sectional view showing a step of an exemplary method according to the present invention.

[0060] Figure 8 Schematically illustrating the implementation Figure 4 A perspective view of an example of a facility with steps.

[0061] Fig. 9 A schematic cross-section of an example of a seat pad manufactured using an exemplary method according to the present invention is shown. DETAILED DESCRIPTION

[0062] In the various figures, the same reference numerals represent the same or similar elements. For the sake of simplicity, only the elements that can be used to understand the described embodiments are shown in the figures and are described in detail below.

[0063] In the following description, when referring to terms defining absolute positions, such as the terms "front", "rear", "top", "bottom", "left", "right", etc., or terms of relative positions, such as the terms "above", "below", "upper", "lower", etc., or directional qualifiers, such as "horizontal", "vertical", etc., unless otherwise specified, the reference is to the orientation of the reference figure or the vehicle seat in its normal use position.

[0064] In particular, the longitudinal direction X is understood to mean the longitudinal direction of the seat. The longitudinal direction of the seat is considered to be identical to the longitudinal direction of the motor vehicle in which the seat is mounted. The longitudinal direction X corresponds to the normal direction of travel of the vehicle. The longitudinal direction X is horizontal. Thus, the transverse direction Y of the seat 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 the vertical direction of the seat, which is perpendicular to the longitudinal direction and the transverse direction.

[0065] Figure 1 A motor vehicle seat 10 is schematically shown mounted on a slide bar mechanism 12 .

[0066] The seat 10 comprises a seat cushion 13 with a seat cushion frame 14 and a seat cushion trim 15, and mounted thereon a backrest 16 with a backrest frame 17 and a backrest trim 18. The backrest frame 17 is pivoted relative to the seat cushion frame 14 about a transverse axis A. For this purpose, a hinge mechanism 20 is arranged between the seat cushion frame 14 and the backrest frame 17.

[0067] The seat cushion 13 is mounted on movable sections 22, also called slides or male sections, via feet 24, 26. Each movable section 22 is part of a slide 12 and is associated with a fixed section 28. The fixed section 28 is also called a "track" or a "female section". The fixed section 28 is attached to the bottom 30 of the motor vehicle.

[0068] In this example, the seat 10 comprises a manual control element 32, referred to as a handle, for controlling the sliding of the slide 12. In particular, this manual control element 32 can lock and unlock a stop system for stopping the movable section 22 from sliding relative to the corresponding fixed section 28. When the stop system is unlocked, the manual control element 32 can also be used to slide the movable section 22 relative to the corresponding fixed section 28 of the slide 12 in the longitudinal direction X of the slide 12. The fixed section 28 and the movable section 22 of the slide 12 are usually metal. Alternatively, the displacement of the movable section 22 relative to the fixed section 28 is controlled by an actuator.

[0069] According to the example shown, the seat 10 may further include a headrest 34. The headrest 34 may further include a headrest frame 35 and a headrest decoration 36 attached to the headrest frame 35. In particular, the headrest frame 35 may be attached to the backrest frame 17 or installed to be slidable relative to the backrest frame 17 in a substantially vertical direction.

[0070] In the following, the manufacture of Figure 1An example of a method of implementing a seat cushion trim 15 in a seat 10 of a vehicle, wherein similar trim can be adapted to different vehicle seat elements. Here, "vehicle seat element" should be understood to mean one of the following:

[0071] - Seat cushion 13;

[0072] - backrest 16;

[0073] - headrest 34;

[0074] -armrest;

[0075] -Backrest height adjustment device;

[0076] - a device for adjusting the length of the seat cushion; and

[0077] - A combination of at least two of the aforementioned elements.

[0078] In particular, the seat element may include a seat cushion 13 and a backrest 16 , and preferably, the seat element consists of the seat cushion 13 and the backrest 16 .

[0079] Figures 2 to 7 An example of a method for producing a trim for a vehicle seat element is shown step by step.

[0080] In this example, the first step consists in placing the cover 40 in the mold M so that it covers at least part of the mold M. In this example, the mold M has a hollow shape, corresponding to the final outer shape of the seat cushion 13, wherein the bottom M1 incorporates a substantially flat central portion M2 surrounded by two hollow side portions M3 and M3'. The mold M also has side pillars, of which two side pillars M4 and M4' are visible. Of course, the shape of the mold M is adapted to the shape of the associated seat element.

[0081] The cover 40 is the seat part visible to the user, i.e. the decorative cover of the seat. For example, the cover is made of fabric, nonwoven, leather, artificial leather or leather.

[0082] like Figure 3 In this example, with Figure 3 The suction system O indicated by the middle arrow performs air suction through the holes in the mold M to hold the cover 40 to the portion on which it is placed on the mold M. Figure 4 and 5 The suction is also schematically shown, showing the step during which the suction system O is still active and in operation, generating a high vacuum to press the cover 40 against the mold M. In addition, in this example, it can be seen that the cover 40 completely covers the mold M, that is, the bottom M1 and the side parts, including the visible side parts M4 and M4'. The suction system O is mounted on the mold M over the entire surface of the cover 40, as shown in FIG. Figures 3 to 5 as shown in .

[0083] Figure 4 The second step shown consists in overmolding a liner 41 onto the cover 40, said liner comprising a 3D entanglement of irregularly arranged continuous thermoplastic fibers 52 forming loops fused together, the liner 41 being seen in a molten state.

[0084] Figure 8 A system is shown for overmolding a cushion 20. Overmolding comprises a first step which includes extruding a plastic material comprising at least one thermoplastic polymer in an extrusion die 46 comprising a plurality of extrusion nozzles 48.

[0085] To this end, polymer particles may be supplied to the extrusion die 46. For example, the extrusion die 46 may be adapted to heat the plastic material, in particular the polymer, to a temperature between 180°C and 240°C.

[0086] According to the example shown, the extrusion nozzles 48 are regularly distributed in two perpendicular directions to form an extrusion nozzle matrix 48. Therefore, the extrusion die 46 can form a curtain 50 of continuous molten fibers 52, the fiber density 52 in its cross section (that is, a plane perpendicular to the forward direction of the extruded fibers 52) is substantially constant. Here, the extrusion nozzles 48 are distributed in a horizontal plane. In addition, in order to keep the density of the fibers 52 substantially constant in the cross section of the curtain 50 of the fibers 52, the fibers 52 are driven by gravity at the outlet of the extrusion die 46.

[0087] Here, a "curtain 50 of fibers 52" is understood to mean a configuration of fibers 52 extending substantially parallel to one another, the fibers 52 forming an envelope curve, here substantially rectangular, in a plane perpendicular to their forward direction that substantially corresponds to the cross section of the extrusion die 46. Alternatively, it can be said that a rain of fibers 52 flows out of the outlet of the extrusion nozzle 48.

[0088] Preferably, at the exit of the extrusion die 46, the temperature of the plastic material forming the fibers 52 is between 180°C and 240°C.

[0089] When deposited on the cover 40 in the mold 24, the fibers 52 tend to form continuous loops that are fused together due to the temperature of the fibers 52. In particular, the fibers 52 may be fused together to obtain a tangle of fused fibers 52. The fibers 52 may be irregularly distributed in the tangle of fibers 52, in particular, according to a distribution that may appear random to an observer.

[0090] Overmolding of the liner just disclosed may result in a substantially uniform liner 20 , ie, having similar fibers 52 and a uniform packing density throughout substantially the entire volume of the liner 20 .

[0091] Figure 4, which is performed simultaneously with the second step, i.e., during the second step, and consists in curing the liner 41 by cooling with a liquid or gas (in this example, liquid E, more precisely water) when the fibers 52 are deposited on the cover 40 in the mold M, thereby fixing the cover 40 and the liner 41 together to obtain the liner. This curing step is performed by immersing in a cooling tank containing liquid E, in this example, water. The initial temperature of the liquid E is between 8° C. and 10° C. In this embodiment, the mold M can be moved relative to the cooling tank, such as Figure 4 , where the two arrows F point downwards, so that the immersion height of the mold M in the tank can be adjusted for this curing step.

[0092] When the amount of fibers 52 deposited in the cover 40 is sufficient to make the pad 41, a step of cutting the fiber entanglement is taken, such as Figure 4 The scissors C are shown schematically.

[0093] In this example, the interstices 43 between the fibers 52 in the 3D fiber entanglement of the pad 41 are free.

[0094] like Figure 5 As shown, the method according to the illustrated embodiment then includes a step comprising thermoforming the liner 41 by applying a thermoforming tool T and hot air along a downward arrow F1 to an outer side 44 of the liner 41 through an opening TO formed on the tool T, the outer side being located on the side opposite to the inner side 45 of the contact cover 40 of the liner 41.

[0095] The purpose of the thermoforming is to shape the portion of the liner 41 which is not in contact with the cover 40 and corresponds to the upper outer face 44 of the liner 41 in the mold M.

[0096] The next step in the process is demoulding.

[0097] Where appropriate, after thermoforming and before or after demoulding, preferably after demoulding, the process may comprise a drying step, which may be brief.

[0098] get Figure 6 The finished, unformed decorative object 49 shown in FIG. Figure 7 As shown, it is turned upside down with the cover 40 located in the upper part and placed on the seat cushion frame 14 to form a seat element, which in this case is a seat cushion.

[0099] This method makes it possible to manufacture the seat element upholstery, including the padding and the cover or cover, in a single step without losing manufacturing quality. The time required to manufacture the seat element is reduced. The padding material makes the whole thing lighter and more breathable. This method is more environmentally friendly than the existing technology, reducing CO2 emissions by about 50%, using recycled materials and the subsequent waste generated can be recycled.

[0100] In addition to the overmolding method described above, Figure 8 The arrangement shown also comprises a control system for opening and closing the extrusion nozzles 48. It is thus possible to open or close at least some of the extrusion nozzles 48 of the extrusion die 46 during the extrusion process. The opening and closing of the extrusion nozzles 48 can be controlled by an electronic control unit 70, in particular a computer.

[0101] The extrusion die 46 is shown here as being vertically located above a tank B having a cooling liquid E, as shown in FIG. Figure 4 It can be seen that the mold M is immersed in the cooling liquid tank B, and the mold M can move in the cooling liquid tank B. In particular, the movement of the mold M can be controlled by the electronic control unit 70. In particular, the mold M can move vertically in the tank B to control the height of the cavity 65 of the mold M immersed in the cooling tank B. In this way, the mold M is filled with continuous molten fibers 52, so that loops are formed between the fibers 52. The fibers 52 immersed in the cooling tank are cooled and hardened to form a continuous fiber entanglement in which the loops are fused together.

[0102] In this example, the thermoplastic fibers of the pad are hollow fibers and / or solid fibers with a diameter between 0.3 mm and 1.5 mm. The composition of the fibers includes at least 95% PET by weight. In this example, the 3D entanglement of the pad 41 has a density of 45 kg / m 3 and 65kg / m 3 The packing density between.

[0103] Fig. 9 An example of a seat element consisting in this case of a seat cushion 13 is shown, the upholstery 49 of which has been produced as described above and then attached to a seat cushion frame 14. The seat cushion 13 is made by providing a seat cushion frame 14 and then attaching thereto the upholstery 49 obtained using the method described above. The thickness of the padding 41 ranges from 30 mm to 120 mm, depending on whether a seat cushion or a backrest is considered. If the seat element is a backrest, an armrest, a headrest, etc., or a combination of these, it is not within the scope of the invention.

[0104] Of course, the invention is not limited to the examples that have just been described.

[0105] In particular, the method may comprise forming said entanglement of molten fibers on the cover by forming a fiber coagulation upstream of two counter-rotating guide members and guiding a curtain of molten fibers between the two guide members, the fibers forming a loop that is fused together.

[0106] When the seat element is a backrest, the thickness of the padding may be between 30 mm and 60 mm.

[0107] According to one embodiment, when the seat element is a backrest, the cushioning layer may include different areas with different packing densities distributed along the longitudinal direction of the cushioning layer, when the seat element is a backrest, and / or when the seat element is a seat cushion, along the longitudinal direction of the cushioning layer, the cushioning layer may include different areas with different packing densities.

Claims

1. A method for producing a trim (49) for a vehicle seat element, the method comprising the following steps: A. placing a cover (40) in the mold (M) such that the cover (40) covers at least part of the mold (M), B. overmolding a liner (41) on the cover (40), the liner comprising a 3D entanglement of irregularly arranged continuous thermoplastic fibers (52) forming loops (43) fused together, the liner (41) being in a molten state, C. Solidifying the liner (41) by cooling with a liquid (E) or a gas, thereby joining the cover (40) and the liner together to obtain the decoration (49).

2. The method according to claim 1, characterized in that: In particular, throughout steps A, B and C, the cover (40) is held by suction to the portion of the mold (M).

3. The method according to any one of the preceding claims, characterized in that Step C is performed simultaneously with step B, and curing is performed while the fibers are arranged on the cover.

4. The method according to any one of the preceding claims, characterized in that Step C is carried out by immersion in a cooling tank (B) containing said liquid (E), in particular water, the initial temperature of said liquid preferably being between 8° C. and 10° C., said mould (M) preferably being movable relative to said cooling tank (B).

5. A method according to any one of the preceding claims, comprising a step D, after carrying out steps A, B and C, of ​​thermoforming the liner (41), in particular by applying a thermoforming tool and heat, in particular hot air, to the outer side (44) of the liner (41), the outer side being located on the side opposite to the inner side (45) of the liner (41) contacting the cover (40).

6. The method according to any one of the preceding claims, comprising a demoulding step E.

7. The method according to any one of the preceding claims, step B comprising the following sub-steps: i. extruding a material comprising at least one thermoplastic polymer into an extrusion die (46) comprising a plurality of extrusion nozzles (48) to form a curtain (50) of molten fibers (52); ii. A tangle of molten fibers (52) is formed on the cover, the fibers (52) forming loops (43) that are fused together.

8. A method for producing a vehicle seat element, comprising the following steps: -Providing a vehicle seat element frame; - manufacturing a trim (49) for a vehicle seat element using a method according to any one of the preceding claims, and - Attaching the trim (49) to the vehicle seat element frame.

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