Roof module for a motor vehicle
View Patent ↗A roof module for motor vehicles is disclosed having an exterior skin, a material layer adjacent thereto, a spacer layer, and a circumferential plastic material.
1. A roof module for a motor vehicle comprising:
an exterior skin;
a material layer having a first major surface fully adjacent to the exterior skin to form a composite, wherein the material layer and the exterior skin have different thermal expansion coefficients, such that the composite remains essentially free of deformation upon a temperature change within a range of from −20° C. to +80° C.; and
a spacer layer adjacent to a second major surface of the material layer, opposite the first major surface, the spacer layer comprising a core material covered by a fiber-reinforced polyurethane layer on one or both major surfaces thereof,
wherein a circumference of the material layer on the second major surface is free from the spacer layer, thereby defining a circumferential zone, the circumferential zone being covered by a fiber-reinforced plastic material.
2. The roof module according to claim 1 , characterized in that the exterior skin comprises at least one of a plastic sheet, a metal foil, or an in-mold coating.
3. The roof module according to claim 1 , characterized in that the exterior skin comprises an exterior skin sheet layer coextruded with exterior skin spacer layer of polycarbonate or acrylonitrile-butadiene-styrene (ABS) and a surface layer of polymethyl methacrylate (PMMA), or a monosheet of ABS.
4. The roof module according to claim 1 , characterized in that the thickness of the exterior skin is from 0.2 mm to 5 mm.
5. The roof module according to claim 4 , characterized in that the thickness of the exterior skin is from 0.5 mm to 1.5 mm.
6. The roof module according to claim 1 , characterized in that the material layer comprises an elastic layer of a polyurethane polymer.
7. The roof module according to claim 1 , characterized in that the material layer has at least one of a modulus of elasticity of from 0.5 MPa to 50 MPa and a thickness of from 0.3 mm to 6 mm.
8. The roof module according to of claim 1 , characterized in that the core material of the spacer layer comprises at least one of expanded plastic material, metal, wood, cardboard, paper, or natural or artificial fibers.
9. The roof module according to claim 8 , characterized in that the core material comprises honeycomb cardboard.
10. The roof module according to claim 9 , characterized in that the honeycomb cardboard have a cell size of from 4 mm to 12 mm.
11. The roof module according to claim 8 , characterized in that the fiber-reinforced polyurethane layer has a thickness of from 0.01 mm to 2 mm and is soaked with a polyurethane polymer.
12. The roof module according to claim 11 , characterized in that the fiber-reinforced polyurethane layer respectively has a thickness of from 0.1 mm to 1 mm.
13. The roof module according to claim 1 , characterized in that the spacer layer has a thickness of from 4 mm to 30 mm.
14. The roof module according to claim 1 , characterized in that the fiber-reinforced plastic material comprises glass-fiber reinforced polyurethane polymer.
15. The roof module according to claim 1 , characterized in that the fiber-reinforced plastic material has a thickness within a range of from 3 mm to 40 mm.
16. The roof module according to claim 1 , characterized in that the fiber-reinforced plastic material covers from 2% to 70% of the surface area of the material layer.
17. The roof module according to claim 16 , characterized in that the fiber-reinforced plastic material covers from 10% to 25% of the surface area of the material layer.
18. The roof module according to claim 1 , characterized in that the thickness of the spacer layer is the same as the thickness of the fiber-reinforced plastic material.