Cushion element for vehicle seat

Abstract

A cushion element (12) for a vehicle seat (10) comprises a foam block comprising an outer surface (24) and a groove (26) comprising a bottom (32) and a side wall (30) leading to the outer surface; the cushion element further comprises an attachment support (22) arranged at the bottom of the groove (26). The attachment support (22) comprises: a contact surface (40) integral with the bottom (32) of the recess; and a rib (42) arranged opposite the contact surface in the direction of the outer surface (24) of the foam block.

Description

Technical Field

[0001] The invention relates to a cushioning element for a vehicle seat, comprising a foam block comprising an outer surface and a recess comprising a bottom and side walls opening onto the outer surface; the cushioning element further comprising an attachment support arranged at the bottom of the recess. Background Art

[0002] Such a cushioning element is known in particular from document FR 2 815 901 in the name of the Applicant.

[0003] In order to fix the seat covering to the cushioning element, it is known to provide said cushioning element with attachment supports inserted into the foam and formed, for example, by metal rods, rigid plastic parts or hook-and-loop fasteners.Such a configuration complicates the operation of recovering the cushioning element. Summary of the Invention

[0004] The object of the present invention is to provide a cushioning element which combines good strength with a construction which facilitates recycling.

[0005] To this end, a subject of the invention is a cushioning element of the aforementioned type, wherein the attachment support comprises a contact surface integral with the bottom of the groove and a rib arranged opposite the contact surface in the direction of the outer surface of the foam block.

[0006] According to further advantageous aspects of the invention, the cushion element comprises one or more of the following features, taken alone or in any technically feasible combination:

[0007] - said attachment support is formed from an unfoamed plastic material;

[0008] - each of the foam of the block and the unfoamed plastic material of the attachment support comprises polyurethane;

[0009] - the contact surface of the attachment support and the ribs extend continuously over the length of the recess of the foam block.

[0010] The invention also relates to a method for manufacturing a cushioning element as described above, comprising the steps of manufacturing the attachment support by molding the unfoamed plastic material; and then manufacturing the foam block by overmolding on the attachment support so as to fix the contact surface of the attachment support to the bottom of the recess of the foam block.

[0011] According to other advantageous aspects of the invention, the manufacturing method comprises one or more of the following features, taken individually or in any technically feasible combination:

[0012] - the step of manufacturing the attachment support comprises: providing a moulding element comprising channels of a shape complementary to the ribs of the attachment support; and pouring plastic material in a fluid state into the channels such that an upper surface of the plastic material forms the contact surface of the attachment support;

[0013] - the molding element comprises side surfaces arranged on either side of the channel, said side surfaces having a shape complementary to the side walls of the recess of the foam block; and the step of manufacturing the foam block comprises overmolding on the molding element housing the attachment support so as to form the recess, the bottom of the recess being integral with the contact surface of the attachment support.

[0014] The invention also relates to a cushioning element as described above, produced by a manufacturing method as described above.

[0015] The invention also relates to a vehicle seat comprising: a cushioning element as described above; a flexible cover in contact with the outer surface of the cushioning element; and a plurality of attachment elements which are attached on the one hand to the flexible cover and on the other hand to the ribs of the attachment support of the cushioning element.

[0016] Optionally, the vehicle seat is such that said plurality of attachment elements comprises at least one metal staple extending between two ends, said ends being inserted into said rib of said attachment support. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The invention will become more apparent on reading the following description, which is given by way of non-limiting example only and with reference to the accompanying drawings, in which:

[0018] Figure 1 is a partial view of a cushion element according to one embodiment of the present invention;

[0019] Figure 2 is included Figure 1 a detailed cross-sectional view of a vehicle seat having a cushioning element; and

[0020] Figure 3 and Figure 4 It is used for manufacturing Figure 1 A schematic diagram of the steps in the method of cushioning an element is shown. DETAILED DESCRIPTION

[0021] Figure 2 is a detailed cross-sectional view of a vehicle seat 10 according to one embodiment of the present invention.

[0022] The seat 10 comprises, inter alia: a cushioning element 12; a covering 14; and a plurality of attachment elements 16. Figure 2A single attachment element 16 is shown in FIG.

[0023] Figure 1 Shown Figure 2 A partial view of the cushion element 12 in cross-section. Figure 1 In the embodiment shown, the cushioning element 12 is used for producing a backrest of the chair 10. According to another embodiment (not shown), the cushioning element is used for producing a seat part of the chair 10.

[0024] The cushion element 12 includes a block 20 and an attachment support 22 .

[0025] The block 20 is formed from an elastically deformable foam consisting of a first plastic material. By "foam" it is meant that the block 20 has a flexible open-cell honeycomb structure (not shown).

[0026] Preferably, the density of the foam forming the block 20 is 30 Kg / m 3 and 100Kg / m 3 Preferably, the foam forming the block 20 has stress-strain properties in compression according to DIN EN ISO 3386 of 3 kPa to 20 kPa.

[0027] Preferably, the first plastic material comprises polyurethane.

[0028] The block 20 includes an outer surface 24 and a recess 26. As described in more detail below, the outer surface 24 is intended to be covered by the cover 14 so as to come into contact with a portion of the body of a user of the chair 10.

[0029] An orthogonal coordinate system (X, Y, Z) is used in connection with the pad element 12. In the embodiment shown, the outer surface 24 of the block 20 extends substantially in the plane (Y, Z).

[0030] Grooves 26 extend on the outer surface 24, as shown Figure 1 More precisely, as Figure 2 As shown, the groove 26 includes two side walls 30 that open to the outer surface 24. The groove 26 also includes a bottom 32 that is arranged opposite the outer surface 24 with respect to the side walls 30.

[0031] In the embodiment shown, the side walls 30 are substantially parallel to one another. Furthermore, in the embodiment shown, the side walls 30 are substantially parallel to the direction X.

[0032] In a variant (not shown), the distance between the side walls of the groove increases slightly between the bottom 32 of the groove and the outer surface 24 of the block 20. For example, the side walls form an angle of between 0° and 15° with each other.

[0033] The depth of the groove 26 in the direction X between the bottom 32 and the outer surface 24 is preferably between 5 mm and 3 cm, more preferably between 15 mm and 25 mm.

[0034] Preferably, the groove 26 extends continuously on the outer surface 24 and includes substantially straight portions and / or curved portions. In the embodiment shown, the groove 26 is substantially U-shaped, including two side portions 34 extending substantially along the Z direction and an upper portion 36 extending substantially along the Y direction. Each side portion 34 is continuous with the upper portion.

[0035] In a variant (not shown), the recess 26 is closed on itself, forming, for example, a rectangle or a square. This shape is particularly suitable for the support part of a chair (not shown).

[0036] According to another variant (not shown), the groove 26 is substantially H-shaped.

[0037] The shape of the grooves 26 on the outer surface 24 provides a certain aesthetic appearance to the cushion element 12 , ensures satisfactory application of the cover 14 to the cushion element 12 , and provides a certain level of comfort for the passenger.

[0038] The attachment support 22 is arranged at the bottom of the groove 26 .

[0039] More specifically, the attachment support 22 comprises a contact surface 40 and a rib 42. The contact surface 40 is integral with the bottom 32 of the groove 26. The rib 42 is arranged opposite the contact surface 40 in the direction of the outer surface 24.

[0040] Preferably, the contact surface 40 and the ribs 42 of the attachment support extend continuously over the length of the foam block's groove 26. Similar to the groove, the attachment support 22 comprises substantially straight portions and / or curved portions.

[0041] Preferably, the attachment support 22 comprises a base 44 forming the contact surface 40. The rib 42 projects from said base 44 opposite the contact surface 40. More preferably, a width 46 of the base 44 perpendicular to the main direction of the groove 26 is greater than a width 48 of the rib 42 perpendicular to the main direction of the groove 26.

[0042] Preferably, the attachment support 22 is formed from a second plastic material. More preferably, the second plastic material is unfoamed, ie the second material does not comprise a porous structure. In other words, the second material is a homogeneous or bulk material.

[0043] Preferably, the density of the second plastic material is 600Kg / m 3 and 900Kg / m 3 Preferably, the second plastic material has a Shore A hardness between 60 and 100.

[0044] Preferably, the second plastic material comprises polyurethane.

[0045] The cover 14 of the seat 10 forms a flexible layer. The cover 14 is formed, for example, from a natural or synthetic textile material, or from natural or synthetic leather.

[0046] The cover 14 includes a main area 50 that contacts the outer surface 24 of the foam block 20 and an attachment area 52 that is disposed in the groove 26 .

[0047] For example, the cover 14 includes multiple layers, specifically a base layer, a split foam layer, and an appearance layer.

[0048] Each of the plurality of attachment elements 16 is attached on the one hand to a rib 42 of the attachment support 22 of the cushioning element 12 and on the other hand to an attachment area 52 of the cover 14 .

[0049] In the embodiment shown, the attachment element 16 has a curved shape extending between two end portions 54. The attachment element 16 also comprises a central portion 56 arranged between said end portions 54.

[0050] Each end 54 of the attachment element 16 is inserted into a rib 42 of the attachment support 22. A central portion 56 of the attachment element 16 is attached to the attachment area 52 of the covering 14.

[0051] Preferably, the attachment element 16 is a metal staple, such as a self-piercing deformable metal staple. Preferably, a plurality of attachment elements 16 are distributed along the length of the groove 26.

[0052] In the embodiment shown, the attachment element 16 is attached in contact with the attachment area 52 of the cover 14. According to a variant (not shown), the seat 10 also comprises a plurality of return elements, each of which is attached on the one hand to a central portion 56 of the attachment element 16 and on the other hand to the attachment area 52 of the cover 14.

[0053] A manufacturing method for the above-described cushion member 12 will now be described.

[0054] The manufacturing method comprises a first step of manufacturing the attachment support 22 by molding a second plastic material, and then a second step of manufacturing the foam block 20 by overmolding onto the attachment support 22. Thus, the contact surface 40 of the attachment support 22 is made integral with the bottom 32 of the recess 26 of the foam block 20.

[0055] Figure 3 and Figure 4 The steps of the above-mentioned manufacturing method are schematically shown.

[0056] In particular, Figure 3 A schematic cross-sectional view of a molding element 60 for performing a first step of manufacturing the attachment support 22 is shown.

[0057] The molding element 60 includes a channel 62 that is complementary in shape to the rib 42 of the attachment support. In the embodiment shown, the molding element 60 includes side surfaces 64 arranged on either side of the channel 62. The shape of the side surfaces 64 is complementary to the shape of the side walls 30 of the groove 26 of the foam block 20. The channel 62 is arranged at one end of the side surfaces 64.

[0058] In the embodiment shown, the molding element 60 is Figure 4 The mould 66 shown is formed in one piece. As a variant, the moulding element 60 is an additional part added and fixed to the mould 66.

[0059] The mold 66 comprises a mold bottom 68 of a shape complementary to the outer surface 24 of the block 20. The side faces 64 of the molding element 60 project from the mold bottom 68, with the channel 62 being arranged opposite said mold bottom.

[0060] The molding element 60 is arranged on the mold bottom 68 along a path corresponding to the path of the groove 26 on the outer surface 24 of the block 20. For example, according to the embodiment shown, the molding element 60 is integral with the mold bottom 68.

[0061] exist Figure 4 In the embodiment shown, the mold 66 also includes a cover 70 that can be removably added to the mold bottom 68 so as to define a closed shell 72. The inner shape of the shell is complementary to the outer shape of the cushion element 12.

[0062] Preferably, the mold 66 includes a vent (not shown) for venting the housing 72 .

[0063] According to a preferred embodiment, the first step of manufacturing the attachment support 22 is carried out as follows:

[0064] First, the molding element 60 is arranged so that the opening of the channel 62 faces upward.

[0065] Then, a first fluid composition 74 is used in a first injection head 76. The first fluid composition 74 is a precursor of the second plastic material forming the attachment support 22.

[0066] Preferably, the first fluid composition 74 is obtained by mixing a first component comprising an isocyanate resin and a second component comprising a polyol. For example, the second component contains one or more polyols, as well as additives. Thus, the first fluid composition 74 allows for the production of a polyurethane.

[0067] More preferably, the water content of the first fluid composition 74 is less than 0.5 wt. % relative to the weight of the polyol, in order to obtain a dense material.

[0068] Next, a first injection head 76 is positioned over the channel 62 of the molding element 60; beads 78 of the first fluid composition 74 are then poured into the channel 62 as the first injection head 76 moves along the length of the channel. Preferably, the cross-section of the beads 78 is about 0.2 cm 2 and 0.6cm 2 Preferably, the flow rate of the first fluid composition 74 is between 3 cm 3 / second and 50cm 3 / second to maintain essentially laminar flow.

[0069] Thus, the channels 62 of the moulding element are filled with the first fluid composition 74. After curing, the upper surface 80 of the second plastic material obtained forms the contact surface 40 of the attachment support 22. The material filling the channels 62 forms the ribs 42 of said attachment support.

[0070] According to a preferred embodiment, the second step of manufacturing the foam block 20 is performed as follows:

[0071] After pouring the first fluid composition 74 , with the attachment support 22 still housed in the channel 62 of the molding element 60 , a second fluid composition 82 ( Figure 4 ). The second fluid composition 82 is a precursor to the foam that forms the mass 20 of the cushioning element 12 .

[0072] According to a preferred embodiment, the second fluid composition 82 comprises a mixture of the above-mentioned first component and the second component, wherein the above-mentioned first component and the second component respectively comprise an isocyanate resin and a polyol. A blowing agent such as water is also added. Preferably, the water content of the second fluid composition 82 is between 0.5% by weight and 6% by weight relative to the weight of the polyol. Therefore, the second fluid composition 82 allows a foamed material, such as a polyurethane foam, to be obtained.

[0073] Next, with the mold 66 open, a second injection head 84 is positioned above the mold bottom 68 and a second fluid composition 82 is poured onto the bottom 68. Preferably, the flow rate of the second fluid composition 82 is greater than 150 cm 3 / Second.

[0074] The mold 66 is then closed by assembling the mold base 68 and the cover 70 together, thereby forming the outer shell 72. The second fluid composition 82 expands, filling the outer shell 72 to form the foam block 20.

[0075] As the second fluid composition 82 expands, it floods the moulding element 60 supporting the attachment support 22. Thus, the contact surface 40 of the support is covered with foam when formed.

[0076] Thus, the groove 26 of the block 20 is formed around the moulding element 60 . Furthermore, the bottom 32 of said groove is attached to the contact surface 40 of the attachment support 22 .

[0077] According to a first alternative, the second fluid composition 82 is poured while the first fluid composition 64 in the channel 62 is still solidifying. According to a second alternative, the second fluid composition 82 is poured after the first fluid composition 74 has solidified. In both cases, good adhesion is achieved between the contact surface 40 of the attachment support 22 and the bottom 32 of the groove 26.

[0078] Preferably, the mold 66 is closed after the second fluid composition 82 has partially expanded. This facilitates venting of the mold.

[0079] Once the second fluid composition 82 solidifies to form the foam block 20, the resulting cushioning element 12 is removed from the mold.

[0080] According to a preferred embodiment, before the first and second steps described above, the manufacturing method comprises applying a release agent to the molding element 60 and the mold bottom 68. This release agent is for example sprayed onto the surface in question in the form of a liquid solution.

[0081] After obtaining the cushioning element 12 , the seat 10 is obtained by nailing each attachment element 16 along the rib 42 of the attachment support 22 , said attachment elements 16 having been previously joined to the attachment area 52 of the covering 14 .

[0082] According to an alternative (not shown), the attachment elements 16 are first pinned along the ribs 42 of the attachment support 22 and the cover 14 is then joined to said attachment elements 16 by means of a plurality of return elements (not shown).

[0083] According to another alternative, the attachment elements 16 are each pinned simultaneously to the attachment area 52 of the covering 14 and the rib 42 of the attachment support 22, for example using a pressure-applying tool that deforms the attachment element 16 so as to pierce the rib 42 and the area 52 and then forms the attachment element 16 into a substantially closed loop.

[0084] For example, the attachment elements 16 are distributed along the ribs 42 such that each attachment element 16 is separated from its neighbors by a substantially regular distance.

[0085] Due to the adhesion between the foam block 20 and the attachment support 22 , the cushioning element 12 described above exhibits good mechanical strength.

[0086] Furthermore, such a cushioning element 12 formed of plastic material without metal inserts facilitates recycling operations.To this end, the foam block 20 and the attachment support 22 are advantageously formed of a similar material, which in particular comprises polyurethane.

Claims

1. A cushioning element (12) for a vehicle seat (10), comprising a foam block (20), the foam block comprising an outer surface (24) and a recess (26), the recess comprising a bottom (32) and side walls (30) leading to the outer surface; the cushioning element further comprising an attachment support (22) arranged at the bottom of the recess (26); The pad element is characterized in that the attachment support (22) comprises: a contact surface (40) integral with the bottom (32) of the groove; and a rib (42) arranged opposite the contact surface in the direction of the outer surface (24) of the foam block.

2. The cushion element according to claim 1, wherein The attachment support (22) is formed from an unfoamed plastic material.

3. The cushion element according to claim 2, characterized in that The foam of the foam block (20) and the unfoamed plastic material of the attachment support (22) each comprise polyurethane.

4. A cushioning element according to any one of the preceding claims, characterized in that The contact surface (40) and the ribs (42) of the attachment support extend continuously over the length of the recess in the foam block.

5. A method for manufacturing a cushion element, wherein the cushion element is a cushion element (12) according to any one of claims 2 to 4, the method comprising the following steps: The attachment support (22) is manufactured by molding the unfoamed plastic material; and the foam block (20) is then manufactured by overmolding on the attachment support so as to fix the contact surface (40) of the attachment support to the bottom (32) of the groove (26) of the foam block.

6. The manufacturing method according to claim 5, characterized in that The steps of manufacturing the attachment support comprise providing a moulding element (60) comprising a channel (62) of a shape complementary to the rib (42) of the attachment support, and pouring plastic material in a fluid state into the channel such that an upper surface (70) of the plastic material forms the contact surface (40) of the attachment support.

7. The manufacturing method according to claim 6, characterized in that: The molding element (60) comprises side surfaces (64) arranged on either side of the channel, said side surfaces having a shape complementary to the side walls (30) of the recess of the foam block; and the step of manufacturing the foam block comprises overmolding on the molding element accommodating the attachment support so as to form the recess (26), the bottom (32) of the recess being integral with the contact surface (40) of the attachment support.

8. A cushioning element (12) according to any one of claims 1 to 4, produced by the manufacturing method according to any one of claims 5 to 7.

9. A vehicle seat (10), comprising: A cushioning element (12) according to any one of claims 1 to 4 or according to claim 8; a flexible cover (14) in contact with the outer surface (24) of the cushioning element; and a plurality of attachment elements (16) attached on the one hand to the flexible cover and on the other hand to the ribs (42) of the attachment support of the cushioning element.

10. The vehicle seat (10) according to claim 9, characterized in that The plurality of attachment elements (16) include at least one metal staple extending between two ends (54) that are inserted into the ribs (42) of the attachment support.

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