Vibration damped article

1. A vibration damped enclosure, comprising side walls and a vibration damping plate structure extending across the enclosure and attached to internal surface portions of a first and a second side wall, wherein the vibration damping plate structure ( 2 ) comprises a non-rigid layer ( 12 ) sandwiched between two rigid layers ( 13 , 14 ), and wherein each rigid layer between said first and second side walls ( 5 , 6 ; 22 , 23 ) comprises at least one cut ( 15 , 16 ) through the rigid layer ( 13 , 14 ) which makes the extension of each rigid layer between the first and second sidewalls ( 5 , 6 ) discontinuous, wherein the at least one cut ( 15 , 16 ) extends completely through an adjacent non-rigid layer ( 12 ).

2. The enclosure according to claim 1 , wherein the damping plate further comprises more than two rigid layers with non-rigid layers between them.

3. The enclosure according to claim 1 , wherein the at least one cut extends along the whole width of the damping plate.

4. The enclosure according to claim 1 , wherein the stiffness (Young's modulus) of the material of the rigid layers ( 13 , 14 ) is at least ten times that of the non-rigid layer.

5. The enclosure according to claim 1 , wherein the non-rigid layer ( 12 ) comprises an elastomer.

6. The enclosure according to claim 5 , wherein the non-rigid layer ( 12 ) is viscoelastic.

7. The enclosure according to claim 1 , wherein each rigid layer ( 13 , 14 ) comprises a metal or metal alloy sheet.

8. The enclosure according to claim 7 , wherein the metal is steel or aluminum.

9. The enclosure according to claim 8 , wherein the damping plate structure ( 2 ) comprises a rubber layer attached to two steel sheets.

10. The enclosure according to claim 1 , wherein the opposed side walls ( 5 , 6 ; 22 , 23 ) of the enclosure comprise fastening means ( 7 , 8 ) for the damping plate structure ( 2 ).

11. The enclosure according to claim 1 , wherein the enclosure is an automotive article.

12. The enclosure according to claim 11 , wherein the automotive article is an oil pan or an engine housing or a chain drive housing or a timing belt cover or a transmission cover or a valve cover or a cam cover.

13. An internal combustion engine block assembly comprising a vibration damped enclosure according to claim 1 .

14. The assembly according to claim 13 , wherein the damping plate structure ( 2 ) is attached to opposite side walls ( 22 , 23 ) within a combustion engine and additionally is attached by attachment means ( 21 ) to at least one bearing cap ( 20 ) for a crankshaft bearing, wherein the extension of each rigid layer between each side wall and each attachment means ( 21 ) to a bearing cap ( 20 ) is discontinuous.

15. Use of a damping plate structure ( 2 ) comprising a non-rigid layer ( 12 ) sandwiched between two rigid layers ( 13 , 14 ), wherein each rigid layer comprises at least one cut ( 15 , 16 ) through the rigid layer ( 13 , 14 ) which makes the extension of each rigid layer between the first and second sidewalls ( 5 , 6 ; 22 , 23 ) discontinuous, wherein the at least one cut ( 15 , 16 ) extends completely through an adjacent non-rigid layer ( 12 ), for vibration damping of an enclosure, especially an automotive enclosure article.

16. A vibration damped enclosure, comprising side walls and a vibration damping plate structure extending across the enclosure and attached to internal surface portions of a first and a second side wall, wherein the vibration damping plate structure ( 2 ) comprises a non-rigid layer ( 12 ) sandwiched between two rigid layers ( 13 , 14 ), and wherein each rigid layer between said first and second side walls ( 5 , 6 ; 22 , 23 ) comprises at least one cut ( 15 , 16 ) through the rigid layer ( 13 , 14 ) which makes the extension of each rigid layer between the first and second sidewalls ( 5 , 6 ) discontinuous, wherein the at least one cut-extends along the whole width of the damping plate.

17. The enclosure according to claim 16 , wherein the at least one cut ( 15 , 16 ) extends at least partially also through an adjacent non-rigid layer ( 12 ).

18. The enclosure according to claim 16 , wherein the damping plate further comprises more than two rigid layers with non-rigid layers between them.

19. The enclosure according to claim 16 , wherein the stiffness (Young's modulus) of the material of the rigid layers ( 13 , 14 ) is at least ten times that of the non-rigid layer.

20. The enclosure according to claim 16 , wherein the non-rigid layer ( 12 ) comprises an elastomer.

21. The enclosure according to claim 20 , wherein the non-rigid layer ( 12 ) is viscoelastic.

22. The enclosure according to claim 16 , wherein each rigid layer ( 13 , 14 ) comprises a metal or metal alloy sheet.

23. The enclosure according to claim 22 , wherein the metal is steel or aluminum.

24. The enclosure according to claim 23 , wherein the damping plate structure ( 2 ) comprises a rubber layer attached to two steel sheets.

25. The enclosure according to claim 16 , wherein the opposed side walls ( 5 , 6 ; 22 , 23 ) of the enclosure comprise fastening means ( 7 , 8 ) for the damping plate structure ( 2 ).

26. The enclosure according to claim 16 , wherein the enclosure is an automotive article.

27. The enclosure according to claim 26 , wherein the automotive article is an oil pan or an engine housing or a chain drive housing or a timing belt cover or a transmission cover or a valve cover or a cam cover.

28. An internal combustion engine block assembly comprising a vibration damped enclosure according to claim 16 .

29. The assembly according to claim 28 , wherein the damping plate structure ( 2 ) is attached to opposite side walls ( 22 , 23 ) within a combustion engine and additionally is attached by attachment means ( 21 ) to at least one bearing cap ( 20 ) for a crankshaft bearing, wherein the extension of each rigid layer between each side wall and each attachment means ( 21 ) to a bearing cap ( 20 ) is discontinuous.

30. Use of a damping plate structure ( 2 ) comprising a non-rigid layer ( 12 ) sandwiched between two rigid layers ( 13 , 14 ), wherein each rigid layer comprises at least one cut ( 15 , 16 ) through the rigid layer ( 13 , 14 ) which makes the extension of each rigid layer between the first and second sidewalls ( 5 , 6 ; 22 , 23 ) discontinuous, wherein the at least one cut extends along the whole width of the damping plate, for vibration damping of an enclosure, especially an automotive enclosure article.