Method for manufacturing a support element for a seat

Abstract

The invention relates to a method for manufacturing a support element (1) for a seat, the support element comprising an outer layer (2) comprising an outer surface and an inner surface (10), a synthetic material skin (4) extending across the inner surface (10) of the outer layer (2), and a first foam layer (6) extending across the synthetic material skin (4). A method comprises the steps of forming the outer layer (2) by applying at least one pigment layer on a first forming surface (24) of a forming tool (20), applying the synthetic material skin (4) on the inner surface (10) of the outer layer (2), and applying the first foam layer (6) on an inner surface (14) of the synthetic material skin (4).

Description

TECHNICAL FIELD

[0001] The present invention relates to a manufacturing method for a support element for a seat.

[0002] The present invention also relates to a support element obtained by the above-mentioned method. BACKGROUND

[0003] The above-mentioned support element forms, for example, a seat cushion or a backrest of a vehicle seat. Such a support element must therefore have sufficient comfort for receiving a passenger in a vehicle and an attractive appearance.

[0004] To this end, the support element is formed from a cushion to which a shell is attached to form the outer surface of the support element. The shell thus gives the support element its appearance, while the cushion is arranged to comfortably accommodate a passenger of the seat. The shell and the cushion are, for example, manufactured independently by molding and are subsequently attached to each other to form the support element of the seat.

[0005] This manufacturing method is therefore cumbersome and time-consuming to implement and requires a plurality of workstations to perform the plurality of steps of manufacturing the support element. SUMMARY

[0006] One object of the present invention is to overcome these drawbacks by proposing a method for manufacturing a support element that can be implemented simply and quickly and that can be performed in a reduced number of workstations.

[0007] To this end, the present invention relates to a manufacturing method for a support element for a seat, the support element comprising at least one outer layer having an outer surface for forming an outer surface of the support element and an inner surface opposite the outer surface, a synthetic material skin extending across the inner surface of the outer layer, and a first foam layer extending across the synthetic material skin, the method comprising the steps of:

[0008] - forming the outer layer by applying at least one pigment layer on a first shaping surface of a shaping tool, the first shaping surface having the shape of the outer surface of the support element to be formed;

[0009] - applying the synthetic material skin on the inner surface of the outer layer, the synthetic material skin being made of a waterproof synthetic material; and

[0010] - applying the first foam layer on the inner surface of the synthetic material skin, the first foam layer having a formulation comprising water and a foaming catalyst at the time of its application to the synthetic material skin.

[0011] The method according to the present invention thus makes it possible to manufacture a support element having a satisfactory appearance and comfort in a reduced number of steps in a single shaping tool.

[0012] According to other optional features of the application, taken individually or according to all technically feasible combinations:

[0013] - the synthetic skin is essentially non-cellular polyurethane, and the first foam layer is cellular polyurethane foam;

[0014] - the first foam layer is formed on the functional film before the first foam layer is applied on the synthetic skin, the assembly formed by the first foam layer and the functional film being applied on the inner surface of the synthetic skin;

[0015] - the functional film is a transfer film, the first foam layer being sprayed onto the transfer film so that the inner surface of the first foam layer extends across the transfer film, the assembly formed by the first foam layer and the transfer film being applied on the synthetic skin so that the outer surface of the first foam layer extends across the inner surface of the synthetic skin, and the transfer film being removed after the outer surface of the first foam layer has been applied on the inner surface of the synthetic skin;

[0016] - a release agent layer is applied on the first forming surface before the pigment layer is applied on the first forming surface;

[0017] - the pigment layer, the synthetic skin and / or the first foam layer are applied by spraying;

[0018] - the pigment layer is applied on the first forming surface by spraying, and the synthetic skin is subsequently applied on the pigment layer by spraying, the first foam layer being applied on the synthetic skin or on the functional film by spraying;

[0019] - the first foam layer is applied on the inner surface of the synthetic skin while the synthetic skin and / or the first foam layer are in a viscous flow state;

[0020] - the method comprises applying a second forming surface of the forming tool on the side of the inner surface of the first foam layer, the second forming surface having the shape of the inner surface of the support element to be formed, and the support element being formed between the first forming surface and the second forming surface in the closed position of the forming tool.

[0021] According to one embodiment of the application, the support element further comprises a cover element extending across the inner surface of the first foam layer and forming the inner surface of the support element, the method comprising the steps of:

[0022] - applying the cover element on the second forming surface of the forming tool before closing the forming tool;

[0023] - closing the forming tool to apply the cover element on the first foam layer in a viscous flow state, so as to bond the cover element and the first foam layer in the forming tool.

[0024] According to this embodiment, the manufacturing method of the application also makes it possible to improve the appearance of the support element by attaching a cover element to the body of the support element so as to give it an inner surface with a satisfactory appearance, in a single operating cycle of the forming tool.

[0025] According to other optional features of this embodiment of the application, taken individually or according to all technically possible combinations:

[0026] - the cover element comprises at least one coating of fabric material, skin or synthetic material, said coating forming the inner surface of the support element;

[0027] - the method comprises a step of forming the cover element before applying it on the second forming surface of the forming tool, in which a second foam layer is applied on a substrate and then bonded to the outer surface of the coating, the assembly formed by the substrate, the second foam layer and the coating being formed so as to substantially conform to the shape of the inner surface of the support element and then placed on the second forming surface of the forming tool, the substrate being removed before applying the second foam layer on the first foam layer;

[0028] - the second foam layer is in a viscous flow state during the formation of the assembly formed by the substrate, the second foam layer and the coating and during the application of the second foam layer on the first foam layer;

[0029] - the cover element is held on the second forming surface by being sucked on the second forming surface of the forming tool, and / or the outer layer is held on the first forming surface by being sucked on the first forming surface;

[0030] - a functional element is placed in the forming tool so as to project into the first foam layer and / or between the first foam layer and the cover element when the forming tool is closed;

[0031] - the functional element is a suspension frame projecting into the first foam layer, said suspension frame being attached to the first forming surface before applying the first foam layer on the inner surface of the synthetic skin;

[0032] - the functional element is a membrane forming at least one cavity defining an inner volume, said membrane extending between the first foam layer and the cover element, and said membrane comprising an opening opening to the outside of the support element of the seat and in fluid communication with the cavity, so that the cavity can be inflated by introducing air into the inner volume through the opening.

[0033] According to another aspect, the present invention also relates to a support element for a seat, comprising: at least one outer layer having an outer surface for forming the outer surface of the support element and an inner surface opposite to the outer surface; and a main body portion extending across the inner surface of the outer layer, the main body portion comprising at least one synthetic material skin extending on the inner surface of the outer layer, the synthetic material skin being made of a waterproof material, and a first foam layer extending on the synthetic material skin, the first foam layer having a water-containing formula.

[0034] According to an optional feature of the support element, the support element further comprises a cover element extending across the inner surface of the body portion and forming the inner surface of the support element. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Further features and advantages of the present invention will become apparent from the following description given by way of example and with reference to the accompanying drawings, in which:

[0036] Figure 1 is a schematic perspective view of a support element according to the present invention, viewed from the side of the outer surface of the support element;

[0037] Figure 2 It is along Figure 1 A schematic diagram of the support element cut along the axis II-II;

[0038] Figures 3-5 are schematic cross-sectional views of different steps in a method for manufacturing a support element according to the invention;

[0039] Figure 6 is a schematic cross-sectional view of a step for manufacturing a support element according to a specific embodiment of the present invention;

[0040] Figure 7 and 8 is based on Figure 6 Schematic cross-sectional view of the steps for manufacturing a support element according to an alternative embodiment of the present invention;

[0041] Figure 9 is a schematic perspective view of a support element according to another embodiment of the present invention;

[0042] Figure 10 is a schematic perspective view of a support element according to another embodiment of the present invention; and

[0043] Figure 11 It is used to manufacture Figure 10 Schematic cross-sectional view of a part of a forming tool for a support element. DETAILED DESCRIPTION

[0044] refer to Figure 1 and2 A vehicle seat support element 1 is described which comprises at least one outer layer 2, a synthetic material skin 4 and a first foam layer 6. According to a particular embodiment which will be described in more detail later on, the support element 1 further comprises a cover element 8.

[0045] The support element 1 is for example used to form a backrest, as shown in Figure 1 Alternatively, the support element 1 can be adapted to form a seat cushion. Such a support element 1 comprises an inner surface for forming a support surface for a seat occupant and an outer surface opposite to said inner surface and forming a surface which is not used to form a support surface for a seat occupant. According to the embodiment shown in the figures, said outer surface is a surface which can at least partially be seen from the outside of the seat. In the following description, the term "inner" refers to the inner surface of the support element 1 and the term "outer" refers to the outer surface of the support element 1.

[0046] The outer layer 2 forms the outer surface of the support element 1. Thus, in the case of a backrest, said outer surface forms the back of the backrest which is opposite to the surface for accommodating the occupant. Opposite to said outer surface, the outer layer 2 defines an inner surface 10 which cannot be seen from the outside of the support element 1.

[0047] The outer layer 2 is formed by at least one pigmented layer, with reference to a particular aspect of the outer surface of the support element 1, which is formed in particular by selecting the color and the gloss of the pigmented layer. For example, the pigmented layer is an aqueous or solvent-based paint. The thickness of the outer layer 2 is for example comprised between 5 μm and 120 μm, preferably between 10 μm and 80 μm, for example about 25 μm. It should be understood that the outer layer 2 can comprise a plurality of pigmented and / or clearcoat layers, depending on the desired appearance of the outer layer 2 and its properties. For example, the outer layer 2 can have abrasion resistance, wear resistance, light resistance, chemical resistance, etc. The outer layer 2 can also have a pattern, for example embossing, logo, etc., which can be formed on the outer layer 2 during the manufacture of the support element 1, which will be described later on.

[0048] The synthetic material skin 4 extends across the inner surface 10 of the outer layer 2 and forms a support of the outer layer 2 by adhesion thereto. The synthetic material skin 4 has an outer surface 12 which extends across the inner surface 10 of the outer layer 2 and an inner surface 14 opposite to the outer surface 12. The synthetic material skin 4 forms a substantially rigid or semi-rigid shell of the support element 1.

[0049] To this end, the synthetic material skin 4 is formed of a water-resistant synthetic material. More particularly, the synthetic material skin 4 is similar to a foam layer which is non-porous, i.e. which does not have perforations. In other words, the synthetic material skin does not contain air bubbles which give it a certain rigidity. It should be noted that the synthetic material skin 4 can contain residual air bubbles due to the method for applying the synthetic material skin 4 which will be described later on.

[0050] The synthetic material skin 4 is for example made of an elastomeric material, such as a material formed by a polyol-isocyanate reaction. According to an embodiment, the synthetic material skin 4 is made of a substantially non-porous, water-repellent polyurethane. The synthetic material skin 4 thus exhibits similar properties as a fabric or leather coated with a synthetic material (TEP).

[0051] For example, the thickness of the synthetic material skin 4 is comprised between 0.1 mm and 3 mm, preferably between 0.5 mm and 2 mm. It should be noted that the synthetic material skin 4 can have a varying thickness depending on the desired properties, in particular the rigidity, of the outer shell of the support element. The density of the synthetic material skin 4 is for example comprised between 400 kg / m 3 and 1500 kg / m 3 , preferably between 800 kg / m 3 and 1200 kg / m 3 . The tensile strength of the synthetic material skin 4 is for example comprised between 1 Mpa and 50 Mpa, preferably between 3 Mpa and 15 Mpa, measured according to the standard DIN EN ISO 527-3 / 2 / 100. The tear strength of the synthetic material skin 4 is for example comprised between 0.5 N / mm -1 and 30 N / mm -1 , preferably greater than 4 N / mm -1 , more preferably greater than 6 N / mm -1 , measured according to the method DIN EN ISO 13937-2.

[0052] The first foam layer 6 extends over the inner surface 14 of the synthetic material skin 4 and is bonded thereto. The first foam layer 6 has an outer surface 16 extending over the inner surface 14 of the synthetic material skin 4 and an inner surface 18 opposite the outer surface 16. The first foam layer 6 forms a cushion of the support element 1 and thus has a certain flexibility.

[0053] To this end, the first foam layer 6 is made of a synthetic material having a water-containing formulation. More particularly, the first foam layer 6 is a cellular foam layer, i.e. a foam layer comprising air bubbles. These cells are obtained during the chemical reaction used to obtain the first foam layer 6, which will be described later.

[0054] The first foam layer 6 is for example made of an elastomeric material, such as a material formed by a polyol-isocyanate reaction using a blowing catalyst. According to an embodiment, the first foam layer 6 is made of a water-containing polyurethane foam.

[0055] The thickness of the first foam layer 6 is comprised between 1 mm and 15 mm, preferably between 4 mm and 9 mm. It should be noted that the first foam layer 6 can have a varying thickness depending on the desired properties, in particular flexibility, of the support element cushion. The rigidity of the first foam layer 6 is comprised between 3 N / 30 mm and 45 N / 30 mm, preferably between 3 N / 30 mm and 25 N / 30 mm.

[0056] The support element 1 described above has a satisfactory appearance on its outer surface side and is suitable for accommodating a passenger on the cushion side. The manufacturing method of such a support element will now be described with reference to Figures 3-5 the attached drawings.

[0057] The support element 1 is manufactured in a forming tool 20 as shown in Figures 3-8 Fig. 2 to obtain a finished support element at the outlet of the forming tool 20.

[0058] The forming tool 20 comprises at least one first part 22 defining a first forming surface 24 having the shape of the outer surface of the support element 1 to be manufactured. Thus, Figures 3-5 the shape of the first forming surface 24 as shown is given by way of example only and other shapes, for example Figures 6-8 as shown, are also conceivable. In addition, the first forming surface 24 can be provided to impart a specific appearance to the outer surface of the support element 1, for example having a local grain and / or pattern, such as a logo or the like, which protrudes from the first forming surface 24 or hollowly extends into the first forming surface 24.

[0059] The steps of the method described below can be performed while the forming tool 20, including the first forming surface 24, is heated, for example to a temperature of approximately 70°C.

[0060] The outer layer 2 is formed by applying at least one layer of paint on the first forming surface 24 so that the outer layer 2 adapts the shape of the first forming surface 24, as Figure 3 shown. The application of the paint layer is performed, for example, by spraying. When the outer layer 2 comprises a plurality of paint and / or varnish layers, they are successively applied on the first forming surface 24 from the outside in, i.e. the layer forming the outer surface, for example a varnish layer, is first applied on the first forming surface 24, then the layer defining the color of the outer surface, for example a paint layer, is applied on the first layer lining the first forming surface 24. The heating of the first forming surface 24 causes the outer layer 2 to dry quickly.

[0061] According to one embodiment, the release agent is first applied on the first forming surface 24 before the outer layer 2 is formed, and the pigment and / or varnish layer(s) are applied on the release agent lining the first forming surface 24. This release agent is for example sprayed onto the first forming surface 24 and helps the removal of the support element 1 formed by the forming tool 20, which will be described later.

[0062] The synthetic material skin 4 is then applied on the inner surface 10 of the outer layer 2, as shown in Figure 4 The synthetic material skin 4 is for example applied by spraying a waterproof material forming the synthetic material skin 4 on the inner surface 10 of the outer layer 2, for example while the outer layer 2 is not yet dry, ensuring the adhesion between the synthetic material skin 4 and the outer layer 2. The material of the synthetic material skin 4 remains in a viscous state after its application and before the application of the first foam layer 6, for example by heating the first portion 22 of the forming tool 20.

[0063] The first foam layer 6 is then applied on the inner surface 14 of the synthetic material skin 4.

[0064] According to the embodiment shown in Figure 5 The first foam layer 6 is formed on the functional film 26 before being applied on the inner surface 14 of the synthetic material skin 4 together with the functional film 26. The functional film 26 is for example a transfer film, a mechanically reinforced mesh, a heat conducting mesh, etc. The application of the foam layer 6 to the functional film 26 is for example done while the functional film 26 is stretched in the frame 28 by applying a foam precursor material on one side of the functional film 26. The foam precursor material serves to form the first foam layer 6 by a chemical reaction, including by means of the foaming catalyst described above. The foaming catalyst is different from water, as the formulation of the foam precursor material already contains water. The chemical reaction between the foam precursor material and the catalyst forms a porous foam on the surface of the functional film 26, and the assembly formed by the first foam layer 6 and the functional film 26 is then applied on the inner surface 14 of the synthetic material skin 4 while the foam layer 6 is in a viscous state. The foam precursor material is for example sprayed on the functional film 26. When the functional film 26 is for example a transfer film for being removed after the first foam layer 6 has been adhered to the synthetic material skin 4, the inner surface 18 of the first foam layer 6 is applied on the functional film 26, as shown in Figure 5 and the outer surface 16 of the first foam layer 6 is applied on the inner surface 14 of the synthetic material skin 4. Alternatively, for a functional film 26 other than a transfer film, the functional film 26 can extend across the outer surface 16 of the first foam layer 6 and be applied on the inner surface 14 of the synthetic material skin 4, so as to be permanently fixed in the support element 1. In any case, the application is done while the synthetic material skin 4 is in a viscous state, ensuring the adhesion between the first foam layer 6, also in a viscous state, or with the functional film 26.

[0065] According to Figure 5 the embodiment shown, the assembly formed by the first foam layer 6 and the functional film 26 is pre-formed before being applied on the inner surface 14 of the synthetic material skin, to take the shape of the inner surface of the support element 1. In this case, the assembly is placed on the second forming surface 30 of the second part 32 of the forming tool 20, which has the shape of the inner surface of the support element 1 to be formed. Thus, at least the inner surface 18 of the first foam layer 6 takes the shape of the inner surface of the support element 1. Like the first part 22, the second part 32 can also be heated.

[0066] The support element 1 is then made by bringing the second part 32 of the forming tool close to the first part 22, so that the assembly formed by the first foam layer 6 and the functional film 26 adheres to the inner surface 14 of the synthetic material skin 4. After the synthetic material skin 4 and the first foam layer 6 have cooled and hardened, the support element 1 forms a mutually coherent assembly of the cushion and the shell attached together, as shown in Figure 1 and 2 The first part 22 and the second part 32 of the forming tool 20 can be separated and the support element 1 can be removed from the forming tool 20, which removal is facilitated when the release agent has been applied on the first forming surface 24. When the functional film 26 is a transfer film, it is removed from the inner surface 18 of the first foam layer 6 after the outer surface 16 of the first foam layer 6 has been applied on the inner surface 14 of the synthetic material skin 4. The support element 1 can thus be used in a seat or subjected to an additional operation of attaching the cover element 8. This operation can be performed outside the forming tool 20, but advantageously can be performed inside the forming tool 20, as will be described later.

[0067] In a variant of the embodiment of Figure 5 , the assembly formed by the first foam layer 6 and the functional film 26 is first applied on the inner surface 14 of the synthetic material skin 4, and then the second part 32 is brought close to the first part 22 to apply the second forming surface 30 on the inner surface of the assembly, to shape it and to bond it to the synthetic material skin 4.

[0068] According to another embodiment, for example when the functional film 26 is not used, the first foam layer 26 is applied directly on the inner surface 14, for example by spraying, as shown in Figure 7 The second forming surface 30 can then be applied on the inner surface 18 of the first foam layer 6, either directly or with the cover element 8 interposed between the second forming surface 30 and the inner surface 18 of the first foam layer 6, as will now be described with reference to Figures 6-8 .

[0069] According to Figure 6In the embodiment shown, the cover element 8 is formed by a covering 34 made of fabric, skin or synthetic material, and includes an inner surface 36 for forming the inner surface of the support element 1 and an outer surface 38 opposite the inner surface 36. It should be understood that the covering 34 can be formed by multiple layers of fabric, skin or synthetic material superimposed on each other.

[0070] According to this embodiment, the coating 34, in particular its inner surface 36, is arranged on the second forming surface 30 of the second part 32 of the forming tool 20 before closing the forming tool, so that when the forming tool 20 is closed, i.e. when the first part 22 and the second part 32 of the forming tool abut each other, the outer surface 38 of the coating 34 is applied to the inner surface 18 of the first foam layer 6 while it is in a viscous state. Figure 6 As shown, if closing the forming tool involves turning over the first part 22 of the forming tool, the outer layer 2, the synthetic material skin 4 and the first foam layer 6 can be held on the first forming surface 24 by being sucked onto the first forming surface 24. Similarly, the cover element 8 can be held on the second forming surface 30 by being sucked onto the second forming surface 30.

[0071] according to Figure 6 In the embodiment shown, the coating 34 is arranged in a flexible state in the forming tool 20 and is adapted to the desired shape by being applied to the second forming surface 30 and the inner surface 18 of the first foam layer 6 and optionally by heating and then cooling the coating 34 in the forming tool. Alternatively, the coating 34 can be preformed, for example, in an intermediate forming tool different from the forming tool 20, so that it has the desired shape when it is arranged on the second forming surface 32.

[0072] according to Figure 7 and 8 In the illustrated embodiment, the cover element 8 further includes a second foam layer 40 extending across the entire outer surface 38 of the covering layer 34. More specifically, the second foam layer 40 includes an inner surface 42 for application to the outer surface 38 of the covering layer 34, and an outer surface 44, opposite the inner surface 42, for application to the inner surface 18 of the first foam layer 6 when the cover element 8 is applied thereto, or to the functional film 26 when the functional film 26 is present. The second foam layer 40 is, for example, made of a material similar to that of the first foam layer 6. For example, the second foam layer 40 is made of porous polyurethane. The thickness of the second foam layer 40 is, for example, similar to that of the first foam layer 6. In other words, the second foam layer 40 has similar properties to the first foam layer 6. Thus, the second foam layer 40, together with the first foam layer 6, forms the cushioning portion of the support element 1.

[0073] according to Figure 7 and 8In accordance with a particular embodiment, the cover element 8 is made and preformed, for example, before being placed on the second forming surface 30 and applied on the first foam layer 6. More particularly, in this case, the second foam layer 40 is applied, for example, on a substrate (not shown) and then on the outer surface 38 of the covering layer 34, the assembly formed by the substrate, the second foam layer 40 and the covering layer 34 being shaped so as to substantially present the shape of the inner surface of the support element 1 and then placed on the second forming surface 30 of the second portion 32 of the forming tool 20. During the shaping of said assembly, the second foam layer 40 is in a viscous flow state. The substrate is then removed before the second foam layer 40 is applied on the first foam layer 6 while the first foam layer 6 and the second foam layer 40 are in a viscous flow state. Such a method for manufacturing the cover element 8 is described, for example, in document FR 2 934 256 and the person skilled in the art can refer to this document for more details on these steps for preforming the cover element 8. The cover element 8 is formed, for example, in a secondary forming tool distinct from the forming tool 20 or by using the second portion 32 of the forming tool 20.

[0074] When the first foam layer 6 is placed on the synthetic skin 4 by the second portion 32 of the forming tool 20, as described with reference to Figure 5 the first foam layer 6 is first applied by closing the forming tool 20, then the second portion 32 is moved away from the first portion 22, thus making it possible to place the cover element 8 on the second forming surface 30. Alternatively, the forming tool 20 comprises a plurality of second portions 32, one of which is used to form the first foam layer 6 and the others to apply the cover element 8, the second portions 32 being successively applied on the first portion 22. This allows to speed up the manufacturing cycle of the support element 1 by performing certain steps in parallel. For example, the first foam layer 6 can be applied on the synthetic skin 4 before applying it on the first foam layer 6, in the case where another second portion 32 is used to receive and / or shape the cover element 8.

[0075] The method for manufacturing the support element 1 described above provides a satisfactory appearance and comfort for the finished support element 1 in one operating cycle of the forming tool 20.

[0076] According to a particular embodiment, one or more functional elements can be integrated during the manufacturing of the support element 1.

[0077] Thus, as Figure 9As shown, the functional element is, for example, a film 46 that forms at least one cavity 48 defining an internal volume. The film includes an opening 50 that opens to the exterior of the support element 1 and is in fluid communication with the cavity 48. Thus, the cavity 48 can be inflated through the opening 50 by connecting its internal volume to an air source (e.g., a pump). The film 46 thus forms an inflatable element for adjusting the comfort of the support element 1 for a passenger resting against the inner surface of the support element. The film 46 extends between the first foam layer 6 and the cover element 8 and can, for example, be integrated into the support element 1 as the functional membrane 26 described above. Alternatively, the film 46 can be positioned between the inner surface 18 of the first foam layer 6 and the cover element 8, after the first foam layer 6 has been formed and before the forming tool 20 is closed. The film 46 can be arranged to remain permanently in the support element 1, or it can be dissolved, for example by melting, upon closing the forming tool 20, thereby forming the cavity(ies) directly in the foam body of the support element 1.

[0078] Alternatively or additionally, as Figure 10 As shown, the functional element is a suspension frame 52 that extends into the first foam layer 6. Such a frame 52 also allows to improve the comfort of the passenger leaning against the inner surface of the support element 1. The frame 52 comprises, for example, a plurality of elastic metal strips 54 extending across the support element 1. The metal strips 54 are provided, for example, with hooks 56 at their ends for fixing the frame 52 to the first part 22 of the forming tool 20, as shown. Figure 11 As shown. To this end, the first portion 22 includes anchoring means 58 for anchoring hooks 56 to the first forming surface 24. The hooks 56 are fixed to the anchoring means 58 to position the frame 52 in the forming tool 20. The frame 52 is attached to the first forming surface 24 before the outer layer 2 and the synthetic material skin 4 are applied to the first forming surface 24. The first foam layer 6 is then formed on the synthetic material skin 4 and the frame 52, for example by spraying as described above. In other words, the frame 52 is overmolded by the first foam layer 6, allowing it to be integrated into the support element 1 during its manufacture.

[0079] The manufacturing method described above thus allows the finished support element 1 to be integrated with several functions in one cycle of the forming tool.

Claims

1. A method for manufacturing a support element (1) for a seat, said support element comprising: at least one outer layer (2) having an outer surface for forming an outer surface of the support element and an inner surface (10) opposite the outer surface; a skin (4) of synthetic material extending over the inner surface (10) of the outer layer (2); and a first layer of foam (6) extending over the synthetic skin (4), the manufacturing method comprising the following steps: - forming the outer layer (2) by applying at least one layer of pigments on a first forming surface (24) of a forming tool (20), the first forming surface (24) having the shape of the outer surface of the support element (1) to be formed; - applying the synthetic skin (4) on the inner surface (10) of the outer layer (2), the synthetic skin (4) being made of a waterproof synthetic material; - applying the first layer of foam (6) on an inner surface (14) of the synthetic skin (4), wherein the first layer of foam (6) has a formulation comprising water and a foaming catalyst at the time of its application to the synthetic skin (4); and - applying a second forming surface (30) of the forming tool (20) on the side of the inner surface (18) of the first layer of foam (6), the second forming surface (30) having the shape of the inner surface of the support element (1) to be formed, and the support element (1) being formed between the first forming surface (14) and the second forming surface (30) in a closed position of the forming tool (20), wherein the support element (1) further comprises a cover element (8) extending over the inner surface (18) of the first layer of foam (6) and forming the inner surface of the support element (1), the manufacturing method further comprising the following steps: - applying the cover element (8) on the second forming surface (30) of the forming tool (20) before closing the forming tool (20); - closing the forming tool (20) to apply the cover element (8) on the first layer of foam (6) in a viscous flow state, thereby causing the cover element (8) and the first layer of foam (6) to bond in the forming tool (20), wherein the cover element (8) comprises at least one layer of fabric, skin or synthetic material (34) forming the inner surface of the support element (1), the manufacturing method further comprising the step of forming the cover element (8) before applying it on the second forming surface (30) of the forming tool (20), wherein a second layer of foam (40) is applied on a substrate and then on an outer surface (38) of the layer of fabric, skin or synthetic material (34), the assembly formed by the substrate, the second layer of foam (40) and the layer of fabric, skin or synthetic material (34) being shaped so as to substantially conform to the shape of the inner surface of the support element (1) and then placed on the second forming surface (30) of the forming tool (20), the substrate being removed before applying the second layer of foam (40) on the first layer of foam (6). ​ 2. The manufacturing method according to claim 1, wherein, The material of the synthetic skin (4) is substantially non-cellular polyurethane and the first foam layer (6) is cellular polyurethane foam.

3. The production method according to claim 1 or 2, wherein The first foam layer (6) is formed on a functional film (26) prior to applying the first foam layer (6) on the synthetic skin (4), the assembly formed by the first foam layer (6) and the functional film (26) is applied on the inner surface (14) of the synthetic skin (4).

4. The manufacturing method according to claim 3, wherein: The functional film (26) is a transfer film, the first foam layer (6) is sprayed onto the transfer film such that the inner surface (18) of the first foam layer (6) extends over the entire transfer film, the assembly formed by the first foam layer (6) and the transfer film is applied on the synthetic skin (4) such that the outer surface (16) of the first foam layer (6) extends over the entire inner surface (14) of the synthetic skin (4) and the transfer film is removed after the outer surface (16) of the first foam layer (6) has been applied on the inner surface (14) of the synthetic skin (4).

5. The production method according to claim 1 or 2, wherein A release agent layer is applied on the first forming surface (24) prior to applying the pigment layer on the first forming surface (24).

6. The production method according to claim 1 or 2, wherein The pigment layer, the synthetic skin (4) and / or the first foam layer (6) are applied by spraying.

7. The manufacturing method according to claim 6, wherein The pigment layer is applied on the first forming surface (24) by spraying and subsequently the synthetic skin is applied on the pigment layer by spraying, wherein the first foam layer (6) is applied on the synthetic skin (4) or a functional film (26) by spraying.

8. The production method according to claim 1 or 2, wherein The first foam layer (6) is applied on the inner surface (14) of the synthetic skin (4) while the synthetic skin (4) and / or the first foam layer (6) are in a viscous flow state.

9. The production method according to claim 1, wherein The second foam layer (40) is in a viscous flow state during the formation of the assembly formed by the substrate, the second foam layer (40) and the cover layer (34) and during the application of the second foam layer (40) on the first foam layer (6).

10. The manufacturing method of claim 1, wherein, The cover element (8) is held on the second forming surface (30) by being adsorbed on the second forming surface (30) of the forming tool (20) and / or wherein the outer layer (2) is held on the first forming surface (24) by being adsorbed on the first forming surface (24).

11. The manufacturing method of claim 1, wherein, A functional element is placed in the forming tool (20) so as to protrude into the first foam layer (6) and / or between the first foam layer (6) and the cover element (8) when the forming tool (20) is closed.

12. The manufacturing method according to claim 11, wherein, The functional element is a hanging frame (52) protruding into the first foam layer (6), the hanging frame (52) being attached to the first forming surface (24) prior to applying the first foam layer (6) on the inner surface (14) of the synthetic skin (4).

13. The manufacturing method of claim 11, wherein, Said functional element is a membrane (46) which forms at least one cavity (48) defining an inner volume, said membrane (46) extending between said first foam layer (6) and said cover element (8) and comprising an opening (50) open to the outside of said support element (1) of the seat and in fluid communication with said cavity (48) so as to enable the inflation of said cavity (48) by introducing air into said inner volume through said opening (50).

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