Method for producing a component of a seat support

Abstract

The seat support element (1) comprises an outer layer (2) having an outer surface and an inner surface (10), a synthetic material skin (4) extending over the inner surface (10) of the outer layer (2), and a first layer of foam (6) extending over the synthetic material skin (4). The method comprises the following steps: - forming the outer layer (2) by applying at least one coat of paint against a first forming surface (24) of a manufacturing tool (20), - applying the synthetic material skin (4) against the inner surface (10) of the outer layer (2), and - applying the first layer of foam (6) against an inner surface (14) of the synthetic material skin (4).

Description

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

[0002] The invention also relates to a support element obtained by such a process.

[0003] Such a support element forms, for example, the seat or backrest of a vehicle seat. Therefore, such a support element must offer satisfactory comfort and appearance for accommodating passengers in the vehicle.

[0004] To achieve this, the support element consists of padding 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 padding is designed to comfortably accommodate the seat occupant. The shell and padding are manufactured separately, for example by molding, and then attached to each other to form the seat support element.

[0005] Such a manufacturing process is therefore tedious and time-consuming to implement and requires a number of workstations to carry out the different manufacturing stages of the support element.

[0006] One of the aims of the invention is to overcome these drawbacks by proposing a method for making a support element that is simple and quick to implement and can be made in a small number of workstations.

[0007] To this end, the invention relates to a method for making a seat support element comprising at least one outer layer, having an external surface, forming an outer surface of the support element, and an inner surface, opposite the external surface, a skin of synthetic material extending over the inner surface of the outer layer, and a first layer of foam extending over the skin of synthetic material, the method comprising the following steps: form the outer layer by applying at least one coat of paint against a first forming surface of a manufacturing tool, said first forming surface having the shape of the outer surface of the support element to be produced, apply the synthetic material skin against the inner surface of the outer layer, the synthetic material skin being made of a water-free synthetic material, and apply the first layer of foam against an inner surface of the synthetic material skin, the first layer of foam having a formulation containing water and a foaming catalyst at the time of its application to the synthetic material skin.

[0008] Thus, the manufacturing process according to the invention makes it possible to produce in a single manufacturing tool a support element having a satisfactory appearance and comfort in a reduced number of steps.

[0009] According to other optional features of the invention, taken individually or in any technically feasible combination: the synthetic material skin is substantially non-cellular polyurethane and the first layer of foam is a cellular polyurethane foam; the first layer is formed on a functional film before the application of the first layer of foam to the synthetic material skin, the assembly formed by said first layer of foam and by said functional film being applied against the inner surface of the synthetic material skin;the functional film is a transfer film, the first layer of foam being sprayed onto said transfer film so that an internal surface of said first layer of foam extends onto the transfer film, the assembly formed by the first layer of foam and the transfer film being applied against the synthetic material skin so that an external surface of the first layer of foam extends onto the internal surface of the synthetic material skin, the transfer film being removed after the application of the external surface of the first layer of foam onto the internal surface of the synthetic material skin; a layer of a release agent is applied against the first forming surface before the application of the paint layer onto said first forming surface; the paint layer, the synthetic material skin and / or the first layer of foam are applied by spraying;The paint layer is spray-applied to the first forming surface, then the synthetic skin material is spray-applied over the paint layer, the first foam layer being spray-applied to the synthetic skin or to a functional film; the first foam layer is applied against the inner surface of the synthetic skin while said synthetic skin and / or said first foam layer are in a viscous state; the process includes applying a second forming surface of the forming tool to the side of an inner surface of the first foam layer, said second forming surface having the shape of an inner surface of the support element to be produced, said support element being formed between the first forming surface and the second forming surface in a closed position of the forming tool.

[0010] According to one embodiment of the invention, the support element further comprises a covering element extending over the inner surface of the first layer of foam and forming the inner surface of the support element, the method comprising the following steps: apply the cover element against the second forming surface of the making tool before closing the making tool, close the making tool so as to apply the cover element against the first layer of foam in the viscous state so as to bond the cover element and the first layer of foam in the making tool.

[0011] Thus, according to this embodiment, the method of implementing the invention also allows, in a single operating cycle of the implementation tool, the improvement of the appearance of the support element by fixing a cover element on the body of the support element so that its inner surface has a satisfactory appearance.

[0012] According to other optional features of this embodiment of the invention, considered individually or in any technically feasible combination: the cover element comprises at least one coating layer of textile material, leather or synthetic material, said coating layer forming the inner surface of the support element; the process includes a step of forming the cover element before its application to the second forming surface of the making tool, in which a second layer of foam is applied to a substrate and then attached to an outer surface of the coating layer, the assembly formed by the substrate, the second layer of foam and the coating layer being shaped to substantially have the shape of the inner surface of the support element and then being placed against the second forming surface of the making tool, the substrate being removed before the application of the second layer of foam to the first layer of foam;the second layer of foam is in a viscous state during the shaping of the assembly formed by the substrate, the second layer of foam and the coating layer and during the application of the second layer of foam on the first layer of foam; the cover element is held against the second forming surface of the making tool by suction against the second forming surface and / or in which the outer layer is held against the first forming surface by suction against the first forming surface; a functional element is placed in the making tool so as to extend into the first layer of foam and / or between the first layer of foam and the cover element when the making tool is closed;The functional element is a suspension frame extending into the first layer of foam, said suspension frame being fixed to the first forming surface before the application of the first layer of foam to the internal surface of the synthetic material skin; the functional element is a film forming at least one pocket defining an internal volume, said film extending between the first layer of foam and the cover element, said film comprising an opening leading to the outside of the seat support element and being in fluidic communication with the pocket so that the pocket can be inflated by introducing air into the internal volume through the opening.

[0013] According to another aspect, the invention also relates to a seat support element comprising at least one outer layer, having an outer surface, forming the outer surface of the support element, and an inner surface, opposite the outer surface, and a body extending over the inner surface of the outer layer, the body comprising at least one skin of synthetic material against the inner surface of the outer layer, the skin of synthetic material being made of a water-free material and a first layer of foam against the inner surface of the skin of synthetic material, the first layer of foam having a formulation containing water.

[0014] According to an optional feature of the support element, the support element further includes a cover element extending over the internal surface of the body and forming the internal surface of the support element.

[0015] Other aspects and advantages of the invention will become apparent from the following description, given by way of example and with reference to the accompanying drawings, in which: [ Fig 1 ] - there Fig. 1 is a schematic perspective representation of a support element according to the invention, viewed from the outer surface of the support element, [ Fig 2 ] - there Fig. 2 is a schematic representation of the support element sliced ​​at axis II-II of the Fig. 1 , [ Fig 3 ] ] Fig 4 ] ] Fig 5 ] - THE Figs. 3 à 5 are schematic cross-sectional representations of different stages of the process for manufacturing a support element according to the invention, [ Fig. 6 ] - there Fig. 6 is a schematic cross-sectional representation of a step in the production of a support element according to a particular embodiment of the invention, [ Fig 7 ] ] Fig 8 ] - THE Figs. 7 And 8are schematic cross-sectional representations of the manufacturing steps of a support element according to a variant of the embodiment method of the Fig. 6 , [ Fig 9 ] - there Fig. 9 is a schematic perspective representation of a support element according to another embodiment of the invention, [ Fig. 10 ] - there Fig. 10 is a schematic perspective representation of a support element according to another embodiment of the invention, and [ Fig 11 ] - there Fig. 11 is a schematic cross-sectional representation of part of a manufacturing tool for producing a support element according to the Fig. 10 .

[0016] With reference to Figs. 1 And 2A vehicle seat support element 1 is described, comprising at least an 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, the support element 1 further comprises a cover element 8.

[0017] Support element 1, for example, is intended to form a seat back, as shown in the Fig. 1 Alternatively, the support element 1 could be adapted to form a seat. Such a support element 1 comprises an inner surface, intended to provide a support surface for a seat occupant, and an outer surface, opposite the inner surface, which is not intended to provide a support surface for a seat occupant. According to the embodiment shown in the figures, the outer surface is at least partially visible from outside the seat. In the following description, the term "inner" refers to anything facing the inner surface of the support element 1, and the term "outer" refers to anything facing the outer surface of the support element 1.

[0018] The outer layer 2 forms the exterior surface of the support element 1. Thus, in the case of a seat back, the outer surface forms the back of the seat, opposite the surface intended to accommodate a passenger. Opposite the exterior surface, the outer layer 2 defines an internal surface 10, not visible from outside the support element 1.

[0019] The outer layer 2 consists of at least one coat of paint that gives a particular appearance to the outer surface of the support element 1, notably by choosing the color and gloss of the paint layer. The paint layer is, for example, a water-based or solvent-based paint. The outer layer 2 has a thickness, for example, between 5 µm and 120 µm, preferably between 10 µm and 80 µm, for example, approximately 25 µm. It is understood that the outer layer 2 may comprise several coats of paint and / or varnish, depending on the desired appearance and properties of the outer layer 2. Thus, the outer layer 2 may have anti-abrasive, wear-resistant, lightfast, chemical-resistant, and other properties.The outer layer 2 may also feature a pattern, such as a grain, a logo or other, this pattern being able to be formed on the outer layer 2 during the making of the support element 1, as will be described later.

[0020] The synthetic material skin 4 extends over the inner surface 10 of the outer layer 2 and forms a support for the outer layer 2 by adhering to it. The synthetic material skin 4 has an outer surface 12, extending over the inner surface 10 of the outer layer 2, and an inner surface 14, opposite the outer surface 12. The synthetic material skin 4 forms a substantially rigid or semi-rigid shell for the support element 1.

[0021] For this purpose, the synthetic material skin 4 is formed from a water-free synthetic material. More specifically, the synthetic material skin 4 resembles a non-cellular foam layer, meaning it lacks cells. In other words, the synthetic material skin does not contain air bubbles, which gives it a certain rigidity. It should be noted that the synthetic material skin 4 may contain residual air bubbles, the presence of which is due to the application process of the synthetic material skin 4, which will be described later.

[0022] The synthetic material skin 4 is, for example, made of an elastomeric material, such as a material resulting from a polyol-isocyanate reaction. In one embodiment, the synthetic material skin 4 is made of substantially non-cellular, water-free polyurethane. Thus, the synthetic material skin 4 exhibits behavior similar to a plastic-coated textile (TEP) or imitation leather.

[0023] The synthetic material skin 4, for example, has a thickness of between 0.1 mm and 3 mm, preferably between 0.5 mm and 2 mm. It should be noted that the thickness of the synthetic material skin 4 can vary depending on the desired characteristics, particularly in terms of rigidity, for the support element's shell. The synthetic material skin 4, for example, has a density of between 400 kg·m⁻³ and 1500 kg·m⁻³, preferably between 800 kg·m⁻³ and 1200 kg·m⁻³. The synthetic material skin 4, for example, has a tensile strength of between 1 MPa and 50 MPa, preferably between 3 MPa and 15 MPa, measured according to the DIN EN ISO 527-3 / 2 / 100 method. The synthetic material skin 4 has, for example, a tear resistance of between 0.5 N.mm -1< and 30 N.mm -1< , preferably greater than 4 N.mm -1< , preferably greater than 6 N.mm -1< , measured according to the DIN EN ISO 13937-2 method.

[0024] The first layer of foam 6 extends over the inner surface 14 of the synthetic material skin 4 and adheres to it. The first layer of foam 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 14. The first layer of foam 6 forms a cushion for the support element 1 and thus exhibits a certain degree of flexibility.

[0025] For this purpose, the first layer of foam 6 is made of a synthetic material with a water-containing formulation. More specifically, the first layer of foam 6 is a cellular foam layer, that is, a foam layer containing air bubbles. These cells are obtained during the chemical reaction used to produce the first layer of foam 6, as will be described later.

[0026] The first layer of foam 6 is, for example, made of an elastomeric material, for example, a material resulting from a polyol-isocyanate reaction using a foaming catalyst. In one embodiment, the first layer of foam 6 is made of a polyurethane foam containing water.

[0027] The first layer of foam 6 has a thickness between 1 mm and 15 mm, preferably between 4 mm and 9 mm. It should be noted that the thickness of the first layer of foam 6 can vary depending on the desired characteristics, particularly in terms of flexibility, for the padding of the support element. The first layer of foam 6 has a rigidity between 3N / 30mm and 45N / 30mm, preferably between 3N / 30mm and 25N / 30mm.

[0028] A support element 1 as described above has a satisfactory appearance on its outer surface and is suitable for accommodating a passenger on the padding side. The method for manufacturing such a support element will now be described with reference to Figs. 3 à 5 .

[0029] Support element 1 is produced in a production tool 20 shown on the Figs. 3 à 8 allowing a finished support element to be obtained at the output of the manufacturing tool 20.

[0030] The manufacturing tool 20 includes at least a first part 22 defining a first forming surface 24 having the shape of the outer surface of the support element 1 to be produced. As such, the shape of the first forming surface 24 represented on the Figs. 3 à 5 is given only as an example and other forms can be considered, as shown for example on the Figs. 6 à 8 . In addition, the first forming surface 24 can be arranged to apply a particular appearance to the outer surface of the support element 1, for example by presenting a grain and / or a localized pattern, such as a logo or other, extending in relief or recess on the first forming surface 24.

[0031] The different stages of the process described below can be carried out while the manufacturing tool 20 is heated, in particular the first forming surface 24, for example to a temperature close to 70°C.

[0032] The outer layer 2 is made by applying at least one layer of paint to the first forming surface 24 so that the outer layer 2 adopts the shape of the first forming surface 24, as shown in the Fig. 3 The paint layer is applied, for example, by spraying. When the outer layer 2 comprises several layers of paint and / or varnish, these are applied successively to the first forming surface 24 from the outside in; that is, the layer forming the outer surface, for example, a layer of varnish, is applied first to the first forming surface 24, and then the layer immediately extending against this first layer, for example, a layer of paint defining the color of the outer surface, is applied against the first layer covering the first forming surface 24. Heating the first forming surface 24 allows for rapid drying of the outer layer 2.

[0033] According to one embodiment, a release agent is first applied to the first forming surface 24 before the external layer 2 is produced, and the paint and / or varnish layer(s) are applied to the release agent coating the first forming surface 24. Such a release agent is, for example, applied by spraying onto the first forming surface 24 and makes it easier to remove the support element 1 produced from the forming tool 20, as will be described later.

[0034] The synthetic material skin 4 is then applied against the inner surface 10 of the outer layer 2, as shown in the Fig. 4 The synthetic material skin 4 is applied, for example by spraying the water-free material forming the synthetic material skin 4 against the inner surface 10 of the outer layer 2, for example while the latter is not yet dry in order to ensure adhesion between the synthetic material skin 4 and the outer layer 2. The material of the synthetic material skin 4 is kept in a viscous state after its application and before the application of the first layer of foam 6, for example by heating the first part 22 of the making tool 20.

[0035] The first layer of foam 6 is then applied to the inner surface 14 of the synthetic material skin 4.

[0036] According to the embodiment shown in the Fig. 5 The first layer of foam 6 is pre-formed on a functional film 26 before being applied, along with the functional film 26, to the inner surface 14 of the synthetic material skin 4. The functional film 26 is, for example, a transfer film, a mechanical reinforcement layer, a thermal layer, or something similar. The application of the foam layer 6 onto the functional film 26 is carried out, for example, while the functional film 26 is stretched within a frame 28, by applying a foam precursor material to one of the faces of the functional film 26. The foam precursor material enables the formation of the first layer of foam 6 through a chemical reaction, notably via a foaming catalyst, as described previously. 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 creates a cellular foam on the face of the functional film 26. The assembly formed by the first foam layer 6 and the functional film 26 is then applied to 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 onto the functional film 26. When the functional film 26 is, for example, a transfer film intended to be removed after the first foam layer 6 adheres to the synthetic material skin 4, the inner surface 18 of the first foam layer 6 is applied to the functional film 26, as shown in the figure. Fig. 5 and the external surface 16 of the first layer of foam 6 is applied to the internal surface 14 of the synthetic material skin 4. Alternatively, for a functional film 26 other than a transfer film, the functional film 26 can be spread over the external surface 16 of the first layer of foam 6 and applied to the internal surface 14 of the synthetic material skin 4 so as to be permanently fixed in the support element 1. In all cases, the application taking place while the synthetic material skin 4 is in a viscous state, adhesion is ensured between the first layer of foam 6, also in a viscous state, or with the functional film 26.

[0037] According to the embodiment shown in the Fig. 5 The assembly formed by the first foam layer 6 and the functional film 26 is pre-formed before being applied to the inner surface 14 of the synthetic material skin to acquire the shape of the inner surface of the support element 1. In this case, this assembly is placed against a second forming surface 30 of a second part 32 of the manufacturing tool 20, the second forming surface 30 having the shape of the inner surface of the support element 1 to be produced. Thus, at least the inner surface 18 of the first foam layer 6 acquires the shape of the inner surface of the support element 1. Like the first part 22, the second part 32 can be heated.

[0038] The support element 1 is then produced by bringing the second part 32 of the forming tool close to the first part 22 so as to adhere the assembly formed by the first layer of foam 6 and the functional film 26 to the inner surface 14 of the synthetic material skin 4. After cooling and hardening of the synthetic material skin 4 and the first layer of foam 6, the support element 1 forms a coherent assembly in which the padding and the shell are fixed to each other, as shown in the Figs. 1 And 2The first and second parts 22, 32 of the forming tool 20 can be separated, and the support element 1 can be removed from the forming tool 20. This operation is facilitated when a release agent has been applied to 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 to the inner surface 14 of the synthetic material skin 4. The support element 1 can then be used in a seat or undergo a further operation of attaching a cover element 8. This operation can be carried out outside the forming tool 20, but it can advantageously be carried out inside the forming tool 20, as will be described later.

[0039] As an alternative to the method of implementation of the Fig. 5 , the assembly formed of the first layer of foam 6 and the functional film 26 is first applied to the internal surface 14 of the synthetic material skin 4 then the second part 32 is brought closer to the first part 22 so as to apply the second forming surface 30 to the internal surface of the assembly in order to give it the shape and so as to secure this assembly to the synthetic material skin 4.

[0040] According to yet another variant, for example when the use of a functional film 26 is not planned, the first layer of foam 26 is applied directly to the internal surface 14, for example by spraying, as shown in the Fig. 7 The second molding surface 30 can then be applied to the inner surface 18 of the first foam layer 6, either directly or with a covering element 8 interposed between the second molding surface 30 and the inner surface 18 of the first foam layer 6, as will now be described with reference to Figs. 6 à 8 .

[0041] According to the embodiment shown in the Fig. 6 , the cover element 8 is formed by a coating layer 34 of textile material, leather or synthetic material and comprising an internal surface 36, forming the internal surface of the support element 1, and an external surface 38, opposite the internal surface 36. It is understood that the coating layer 34 can be formed of several superimposed layers of textile material, leather or synthetic material.

[0042] According to this embodiment, the coating layer 34, more particularly its inner surface 36, is positioned against the second forming surface 30 of the second part 32 of the manufacturing tool 20 before the tool is closed, so that the outer surface 38 of the coating layer 34 is applied to the inner surface 18 of the first foam layer 6 while the latter is in a viscous state when the manufacturing tool 20 is closed, i.e., when the first and second parts 22, 32 of the manufacturing tool are brought together. If closing the manufacturing tool involves flipping the first part 22 of the manufacturing tool 20, as shown in the Fig. 6 The outer layer 2, the synthetic material skin 4 and the first foam layer 6 can be held against the first forming surface 24 by suction against this first forming surface 24. Similarly, the cover element 8 can be held against the second forming surface 30 by suction against the second forming surface 30.

[0043] Depending on the method of implementation of the Fig. 6 The coating layer 34 is placed in a flexible state within the forming tool 20 and takes on the desired shape through its application against the second forming surface 30 and against the internal surface 18 of the first foam layer 6, and optionally through heating and then cooling the coating layer 34 within the forming tool. Alternatively, the coating layer 34 can be pre-formed, for example in an intermediate forming tool, different from the forming tool 20, so as to have the desired shape when placed against the second forming surface 32.

[0044] Depending on the method of implementation of Figs. 7 And 8The cover element 8 further comprises a second layer of foam 40 extending over the outer surface 38 of the coating layer 34. More specifically, the second layer of foam 40 comprises an inner surface 42, applied to the outer surface 38 of the coating layer 34, and an outer surface 44, opposite the inner surface 42, applied against the inner surface 18 of the first layer of foam 6 when the cover element 8 is applied to the first layer of foam 6, or against the functional film 26 when the latter remains present. The second layer of foam 40 is, for example, made of a material similar to that of the first layer of foam 6. Thus, the second layer of foam 40 is, for example, made of cellular polyurethane. The second layer of foam 40 has, for example, a thickness close to that of the first layer of foam 6.In other words, the second layer of foam 40 has similar characteristics to the first layer of foam 6. The second layer of foam 40 thus forms part of the padding of the support element 1 with the first layer of foam 6.

[0045] Depending on the method of implementation of Figs 7 And 8The cover element 8 is, for example, manufactured and preformed before being placed against the second forming surface 30 and applied to the first layer of foam 6. More specifically, in this case, the second layer of foam 40 is, for example, applied to a substrate (not shown) and then transferred to the outer surface 38 of the coating layer 34. The assembly formed by the substrate, the second layer of foam 40, and the coating layer 34 is shaped to substantially resemble the inner surface of the support element 1 and then placed against the second forming surface 30 of the second part 32 of the manufacturing tool 20. During the shaping of this assembly, the second layer of foam 40 is in a viscous state. The substrate is then removed before the second layer of foam 40 is applied to the first layer of foam 6, while the first and second layers of foam 6 and 40 are in a viscous state.Such a process for producing the cover element 8 is described for example in document FR-2 934 256 and the person skilled in the art may refer to it for more details regarding these preforming steps of the cover element 8. The cover element 8 is produced for example in an auxiliary production tool different from the production tool 20 or by using the second part 32 of the production tool 20.

[0046] When the first layer of foam 6 is applied to the synthetic material skin 4 by means of the second part 32 of the making tool 20, as described with reference to the Fig. 5 The first layer of foam 6 is initially applied by closing the forming tool 20. Then, the second part 32 is separated from the first part 22 to allow the cover element 8 to be positioned against the second forming surface 30. Alternatively, the forming tool 20 comprises several second parts 32, one of which is used to form the first layer of foam 6 and another to apply the cover element 8, with the second parts 32 being successively applied against the first part 22. This accelerates the production cycle of the support element 1 by performing certain steps in parallel. For example, the first layer of foam 6 can be applied against the synthetic material skin 4 while another second part 32 is used to receive and / or shape the cover element 8 before applying it to the first layer of foam 6.

[0047] The manufacturing process for support element 1 described above makes it possible to obtain a finished support element 1 with a satisfactory appearance and comfort in one operating cycle of the manufacturing tool 20.

[0048] According to particular embodiments, one or more functional elements can be integrated into the support element 1 during its fabrication.

[0049] Thus, as depicted on the Fig. 9 The functional element is, for example, a film 46 forming at least one pocket 48 defining an internal volume. The film includes an opening 50 leading to the outside of the support element 1 and being in fluidic communication with the pocket 48. Thus, the pocket 48 can be inflated by connecting its internal volume to an air source, such as a pump, via the opening 50. The film 46 thus forms an inflatable element allowing the comfort of the support element 1 to be modified for a passenger leaning against the inner surface of the support element. The film 46 extends between the first layer of foam 6 and the cover element 8 and can, for example, be integrated into the support element 1 in the same way as the functional film 26, as described previously.Alternatively, the film 46 is positioned between the inner surface 18 of the first foam layer 6 and the cover element 8 before the forming tool 20 is closed, while the first foam layer 6 is already formed. The film 46 can be arranged to remain permanently in the support element 1 or to degrade upon closure of the forming tool 20, for example by melting, so that the pocket(s) are formed directly in the foam of the support element 1.

[0050] As an alternative or supplement, and as shown on the Fig. 10 The functional element is a suspension frame 52 extending into the first layer of foam 6. Such a frame 52 also improves the comfort of a passenger leaning against the inner surface of the support element 1. The frame 52 comprises, for example, a plurality of elastic metal slats 54 extending across the support element 1. The metal slats 54 are, for example, provided with hooks 56 at their ends for attaching the frame 52 to the first part 22 of the embodiment tool 20, as shown in the Fig. 11To this end, the first part 22 includes anchoring means 58 for the hooks 56 on the first forming surface 24, to which the hooks 56 are attached for positioning the reinforcement 52 in the forming tool 20. The reinforcement 52 is fixed to the first forming surface 24 after the application of the outer layer 2 and the synthetic material skin 4 to the first forming surface 4. The first layer of foam 6 is then formed over the synthetic material skin 4 and over the reinforcement 52, for example, by spraying, as described previously. In other words, the reinforcement 52 is overmolded by the first layer of foam 6, which allows it to be integrated into the support element 1 during its production.

[0051] The manufacturing process described above thus makes it possible to obtain a finished support element 1 integrating several functionalities in one operating cycle of the manufacturing tool.

Claims

1. A method for producing a seat support element (1), comprising at least one outer layer (2), having an outer surface, forming an exterior surface of the support element, and an inner surface (10), opposite the outer surface, a skin of synthetic material (4) extending over the inner surface (10) of the outer layer (2), and a first layer of foam (6) extending over the skin of synthetic material (4), the method comprising the following steps: - forming the outer layer (2) by applying at least one layer of paint against a first forming surface (24) of a manufacturing tool (20), said first forming surface (20) having the shape of the outer surface of the support element (1) to be produced, - applying the skin of synthetic material (4) against the inner surface (10) of the outer layer (2), the skin of synthetic material (4) being made of a water-free synthetic material,and - apply the first layer of foam (6) against an internal surface (14) of the synthetic material skin (4), the first layer of foam (6) having a formulation containing water and a foaming catalyst at the time of its application to the synthetic material skin (4).

2. A method of embodiment according to claim 1, wherein the synthetic material skin (4) is substantially non-cellular polyurethane and the first foam layer (6) is a cellular polyurethane foam.

3. Method of embodiment according to claim 1 or 2, wherein the first layer (6) is formed on a functional film (26) before the application of the first layer of foam (6) on the synthetic material skin (4), the assembly formed by said first layer of foam (6) and by said functional film (26) being applied against the inner surface (14) of the synthetic material skin (4).

4. A method of embodiment according to claim 3, wherein the functional film (26) is a transfer film, the first layer of foam (6) being sprayed onto said transfer film so that an internal surface (18) of said first layer of foam (6) extends over the transfer film, the assembly formed by the first layer of foam (6) and the transfer film being applied against the synthetic material skin (4) so ​​that an external surface (16) of the first layer of foam (6) extends over the internal surface (14) of the synthetic material skin (4), the transfer film being removed after the application of the external surface (16) of the first layer of foam (6) to the internal surface (14) of the synthetic material skin (4).

5. Method of embodiment according to any one of claims 1 to 4, wherein a layer of a release agent is applied against the first forming surface (24) before the application of the paint layer on said first forming surface (24).

6. Method of embodiment according to any one of claims 1 to 5, wherein the paint layer, the synthetic material skin (4) and / or the first foam layer (6) are applied by spraying.

7. A method of embodiment according to claim 6, wherein the paint layer is spray-applied onto the first forming surface (24), then the synthetic material skin material is spray-applied onto the paint layer, the first foam layer (6) being spray-applied onto the synthetic material skin (4) or onto a functional film (26).

8. A method of embodiment according to any one of claims 1 to 7, wherein the first layer of foam (6) is applied against the inner surface (14) of the synthetic material skin (4) while said synthetic material skin (4) and / or said first layer of foam (6) are in a viscous state.

9. A method of embodiment according to any one of claims 1 to 8, further comprising applying a second forming surface (30) of the making tool (20) to the side of an internal surface (18) of the first layer of foam (6), said second forming surface (30) having the shape of an internal surface of the support element (1) to be made, said support element (1) being formed between the first forming surface (14) and the second forming surface (30) in a closed position of the making tool (20).

10. Method of embodiment according to claim 9, the support element (1) further comprising a cover element (8) extending over the internal surface (18) of the first layer of foam (6) and forming the internal surface of the support element (1), the method comprising the following steps: - applying the cover element (8) against the second forming surface (30) of the making tool (20) before closing the making tool (20), - closing the making tool (20) so as to apply the cover element (8) against the first layer of foam (6) in the viscous state so as to bond the cover element (8) and the first layer of foam (6) in the making tool (20).

11. Method of embodiment according to claim 10, wherein the cover element (8) comprises at least one coating layer (34) of textile material, leather or synthetic material, said coating layer (34) forming the inner surface of the support element (1).

12. Method of embodiment according to claim 11, comprising a step of forming the cover element (8) before its application on the second forming surface (30) of the making tool (20), in which a second layer of foam (40) is applied on a substrate and then attached to an external surface (38) of the coating layer (34), the assembly formed by the substrate, the second layer of foam (40) and the coating layer (34) being shaped to substantially have the shape of the inner surface of the support element (1) and then being placed against the second forming surface (30) of the making tool (20), the substrate being removed before the application of the second layer of foam (40) on the first layer of foam (6).

13. Method of embodiment according to claim 12, wherein the second layer of foam (40) is in a viscous state during the shaping of the assembly formed by the substrate, the second layer of foam (40) and the coating layer (34) and during the application of the second layer of foam (40) on the first layer of foam (6).

14. A method of embodiment according to any one of claims 10 to 13, wherein the cover element (8) is held against the second forming surface (30) of the embodiment tool (20) by suction against the second forming surface (30) and / or wherein the outer layer (2) is held against the first forming surface (24) by suction against the first forming surface (14).

15. A method of embodiment according to any one of claims 10 to 14, wherein a functional element is placed in the embodiment tool (20) so as to extend into the first layer of foam (6) and / or between the first layer of foam (6) and the cover element (8) when the embodiment tool (20) is closed.

16. Method of embodiment according to claim 15, wherein the functional element is a suspension frame (52) extending into the first layer of foam (6), said suspension frame (52) being fixed to the first forming surface (14) before the application of the first layer of foam (6) onto the internal surface (14) of the synthetic material skin (4).

17. A method of embodiment according to claim 15, wherein the functional element is a film (46) forming at least one pocket (48) defining an internal volume, said film (46) extending between the first layer of foam (6) and the cover element (8), said film (46) comprising an opening (50) leading to the outside of the seat support element (1) and being in fluidic communication with the pocket (48) so that the pocket (48) can be inflated by introducing air into the internal volume through the opening (50).