ACOUSTIC PROTECTION COVER FOR ENCAPSULATING A MOTOR VEHICLE COMPONENT

Abstract

An acoustic protection cover for encapsulating a motor vehicle component, the cover including: a based on injection-molding material, the material comprising a thermoplastic matrix and a filler that is dispersed in such a way as to exhibit a density of between 1.3 and 1.6, the shell comprising two half-shells delimited by a thin region originating from the molding and forming a flexible hinge; a layer of elastically compressible foam overmolding the internal face of the shell, so that the cover forms an insulation system of the mass-spring type, the mass being formed by the shell and the spring by the layer; a means of holding the half-shells together once the hinge has been folded, so as to allow the component to be encapsulated, the matrix being made of polyvinyl butyral (PVB) and the level of filling being less than or equal to 50% by mass of the material.

Claims

1. An acoustic protection cover for encapsulating a motor vehicle component, said cover comprising: a shell based on injection-molded material, said material comprising a thermoplastic matrix and a filler that is dispersed in such a way as to exhibit a density of between 1.3 and 1.6, said shell comprising two half-shells delimited by a thin region originating from the molding and forming a flexible hinge, a layer of elastically compressible foam overmolding the internal face of said shell, so that said cover forms an insulation system of the mass-spring type, the mass being formed by said shell and the spring by said layer, a means of holding said half-shells together once said hinge has been folded, so as to allow said component to be encapsulated, wherein said matrix is made of polyvinyl butyral (PVB), and the level of filling is less than or equal to 50% by mass of said material.

2. The cover according to claim 1, the level of filling being between 42% and 46% by mass of the material of the shell.

3. The cover according to claim 1, the means of holding comprise including a lug coming from material of the shell and a slot, produced in said shell, for receiving said lug by nesting.

4. The cover according to claim 1, the filler being one of mineral or metal.

5. The cover according to claim 1, the compressible layer being based on flexible polyurethane foam.

6. The architecture for mounting an acoustic protection cover according to claim 1, said architecture comprising said cover and a motor vehicle component to be protected, said cover being mounted with the layer of foam arranged with tight contact around said component.

7. A method for producing a cover according to claim 1, said method comprising the step of separating the polyvinyl butyral comprised in a laminated glass intended for recycling in order to produce the shell.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DISCLOSURE

[0026] Other particularities and advantages of the invention shall appear in the following description, given in reference to the attached figures, wherein:

[0027] FIG. 1 is a cross-section diagrammatical view of a cover, with the hinge not folded,

[0028] FIG. 2 is a cross-section diagrammatical view of the cover of FIG. 1 once mounted around a motor vehicle component, with the hinge folded and with the means of holding the half-shells activated.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] In reference to the figures, an acoustic protection cover 1 for encapsulating a motor vehicle component 2 is described, the cover comprising:

[0030] a shell 3 based on injection-molded material, the material comprising a thermoplastic matrix and a filler that is dispersed in such a way as to exhibit a density of between 1.3 and 1.6, the shell including two half-shells 4a, 4b delimited by a thin region originating from the molding and forming a flexible hinge 5,

[0031] a layer of elastically compressible foam 6 overmolding the internal face of said shell, so that said cover forms an insulation system of the mass-spring type, the mass being formed by the shell and the spring by said layer,

[0032] a means 7 of holding the half-shells together once the hinge has been folded, so as to allow the component to be encapsulated,

[0033] the cover further having the following characteristics:

[0034] the matrix is made of polyvinyl butyral (PVB),

[0035] the level of filling is less than or equal to 50% by mass of the material.

[0036] According to an embodiment, the level of filling is between 42% and 46% by mass of the material of the shell 3.

[0037] According to the embodiment shown, the means of holding 7 includes a lug 8here provided with a harpoon end 10coming from material of the shell 3 and a slot 9, produced in the shell, for receiving the lug by nesting.

[0038] According to an embodiment, the filler is mineralbeing for example in the form of calcite or baryteor metal.

[0039] According to an embodiment, the compressible foam 6 is based on flexible polyurethane foam.

[0040] An architecture for mounting an acoustic protection cover 1 is now described, said architecture comprising said cover and a motor vehicle component 2 to be protected, said cover being mounted with the layer of foam 6 arranged in tight contact around said component, in particular against a casing that is part of said component.

[0041] Finally, a method for producing a cover 1 is described, the method including separating the polyvinyl butyral comprised in a laminated glass intended for recycling in order to produce the shell 3.

[0042] A major interest in deploying such a method is that the recycled PVB does not have sufficient quality to be reused in the manufacture of laminated glass; this here is therefore a recycling sector that is highly suitable for PVB.

[0043] Note that PVB, due to its very low melting point (about 110 C.) and of its amorphous natureopposite the polyolefins used in prior art which are semi-crystallineallows for a repeated folding of the hinge 5 at the output of the mold while the shell 3 is still hot, which allows for an orientation in molecular chains that makes said hinge even more robust.

[0044] The overmolding of the cover 1 by the layer of foam 6 is carried out by setting the shell 3 in place in a mold, with the hinge 5 not folded, and injecting a precursor mixture of elastically compressible foam onto the internal face of said shell.