Solar generator with energy damping for satellites

• US 5,994,640 A
• Filed: 04/16/1998
• Issued: 11/30/1999
• Est. Priority Date: 04/16/1997
• Status: Expired due to Fees

• Current Assignee: Eurocopter Deutschland Gesellschaft Mit Beschrã¤Nkter Haftung (European Aeronautic Defence and Space Company EADS NV)
• Original Assignee: Eurocopter Deutschland Gesellschaft Mit Beschrã¤Nkter Haftung (European Aeronautic Defence and Space Company EADS NV)
• Inventors: Gietl, Albert, Bauer, Markus, Bansemir, Horst, Haider, Ottmar
• Primary Examiner(s): CHAPMAN, MARK A
• Application Number:
  US09/061,466
• Time in Patent Office: 593 Days
• Field of Search: 136/244, 136/292, 428/116, 52/793.1, 52/793.11, 52/173.3
• US Class Current: 136/244
• CPC Class Codes: B32B 3/12 characterised by a layer of regularly- arranged cells, e.g. a honeycomb structure
• CPC Class Codes: B64G 1/228 Damping of high-frequency vibration effects on spacecraft elements, e.g. by using acoustic vibration dampers
• CPC Class Codes: B64G 1/38 damping of oscillations, e.g. nutation dampers
• CPC Class Codes: B64G 1/443 Photovoltaic cell arrays
• CPC Class Codes: F16F 15/08 with rubber springs grommet- or bushing-type resilient mountings F16F1/3732, F16F1/38; with springs made of rubber and metal arrangement of internal-combustion or jet-propulsion units B60K5/12; mounting of propulsion plants on vessels B63H21/30; mounting of vehicle drivers' cabs B62D33/0604
• CPC Class Codes: H01L 31/048 Encapsulation of modules
• CPC Class Codes: H02S 20/20 Supporting structures directly fixed to an immovable object H02S20/30 takes precedence
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y10S 136/292 Space - satellite
• CPC Class Codes: Y10T 428/24149 Honeycomb-like

Abstract

A solar generator for use in satellites or spacecraft includes a plurality of solar cells mounted on a support structure panel. The support structure panel includes a honeycomb cell structure core (4) sandwiched between a bottom cover skin (5) and a top cover skin (2). Vibration damping elements (11) are incorporated and bonded into the honeycomb core, and vibration damping film strips (10) are adhesively bonded onto an outer surface of at least one of the outer cover skins. The damping elements (11) respectively include a damping ring (13) made of an elastomeric material, between inner and outer structural rings (14, 12), whereby the outer ring is bonded to the honeycomb core and the inner ring provides a mounting location. The damping film strips are positioned at locations of maximum vibrational excitation in the panel due to noise pressure loading. The damping elements damp vibrations in the range from 30 Hz to 100 Hz, and the damping film strips damp noise pressure loads in the frequency range from 150 Hz to 500 Hz.

Claims

1. A solar generator comprising a support structure and a plurality of solar cells mounted on said support structure, wherein said support structure comprises a first cover skin, a second cover skin, a honeycomb cell structure core arranged between said first and second cover skins such that honeycomb cells of said core are oriented with lengthwise axes of said cells extending perpendicular to at least one of said cover skins, and a plurality vibration of damping elements respectively arranged in respective holes in said core.

2. The solar generator of claim 1, wherein each one of said damping elements has a circular cylindrical shape, and said respective holes in said core are circular cylindrical bored holes.

3. The solar generator of claim 2, wherein each one of said damping elements respectively comprises a cylindrical annular outer ring made of a metal or a fiber-reinforced composite material, an elastomer ring made of an elastomer material arranged within and fixed to said outer ring, and an inner member made of a metal or a fiber-reinforced composite material arranged within and fixed to said elastomer ring.

4. The solar generator of claim 3, wherein said inner member comprises a cylindrical annular inner ring.

5. The solar generator of claim 3, wherein said outer ring and said inner member are respectively made of said fiber-reinforced composite material.

6. The solar generator of claim 3, wherein said outer ring and said inner member are respectively made of said metal.

7. The solar generator of claim 3, wherein said outer ring is made of said fiber-reinforced composite material, and said inner member is made of said metal.

8. The solar generator of claim 3, wherein said outer ring and said inner member are bonded to said elastomer ring by vulcanizing of said elastomer material.

9. The solar generator of claim 3, further comprising at least one intermediate ring made of a metal or a fiber-reinforced composite material and at least one other ring made of an elastomer material arranged alternating with each other between said elastomer ring and said outer ring.

10. The solar generator of claim 2, wherein said damping elements are respectively received and enclosed in said core between said first and second cover skins.

11. The solar generator of claim 10, further comprising locally limited reinforcement layers respectively arranged between said core and said cover skins to cover said holes and said damping elements.

12. The solar generator of claim 1, further comprising a plurality of vibration damping film strips spaced apart from one another and adhesively bonded onto an outer surface of at least one of said first and second cover skins.

13. The solar generator of claim 12, wherein said damping film strips are bonded onto said outer surface of said first cover skin, and further comprising an electrically insulating layer arranged on an opposite outer surface of said second cover skin.

14. The solar generator of claim 12, wherein said damping film strips include different strips respectively having at least one of different widths and different lengths.

15. The solar generator of claim 12, wherein at least a respective one of said damping film strips is a built-up multi-layer strip adhesively bonded onto said outer surface.

16. The solar generator of claim 12, wherein said damping film strips are continuous strips.

17. The solar generator of claim 12, wherein said damping film strips are discontinuous interrupted strips.

18. The solar generator of claim 12, wherein said damping film strips and said first and second cover skins all comprise a resin impregnated fiber material.

19. The solar generator of claim 12, wherein said damping film strips have a stiffness matched to a stiffness of said at least one cover skin.

20. The solar generator of claim 12, wherein said damping film strips include respective strips extending in directions that are perpendicular to each other.

21. The solar generator of claim 12, wherein said damping film strips are arranged at locations on said at least one cover skin that are subject to greatest vibrational excitation.

22. The solar generator of claim 12, wherein each one of said damping elements respectively comprises a cylindrical annular outer ring made of a metal or a fiber-reinforced composite material, an elastomer ring made of an elastomer material arranged within and bonded to said outer ring, and a cylindrical annular inner ring made of a metal or a fiber-reinforced composite material arranged within and bonded to said elastomer ring.

23. The solar generator of claim 22, further comprising at least one intermediate ring made of a metal or a fiber-reinforced composite material and at least one other ring made of an elastomer material arranged alternating with each other between said elastomer ring and said outer ring.

24. The solar generator of claim 22, wherein at least one of said outer ring and said elastomer ring comprises a plurality of independent annular cylinder sectors.

25. The solar generator of claim 12, wherein said damping elements are so constructed and arranged to be adapted to damp vibrations selectively in a frequency range from 30 Hz to 100 Hz, and said damping film strips are so constructed and arranged to be adapted to damp vibrations selectively in a frequency range from 150 Hz to 500 Hz.

26. The solar generator of claim 1, wherein each said damping element has an outer wall that is bonded to said core.

27. The solar generator of claim 1, further comprising locally limited reinforcement layers respectively arranged between said core and said cover skins to cover said holes and said damping elements, wherein respective end faces of said damping elements are bonded to said cover skins by said reinforcement layers.

28. A composite sandwich structural panel with vibration damping, comprising first and second cover skins of resin impregnated fiber composite material, a honeycomb cell structure core sandwiched between said first and second cover skins, vibration damping elements arranged in holes in said core and respectively bonded to said core, and vibration damping film strips adhesively bonded onto an outer surface of at least one of said first and second cover skins.

29. The structural panel of claim 28, wherein said damping elements provide said vibration damping selectively in a frequency range from 30 Hz to 100 Hz, and said damping film strips provide said vibration damping selectively in a frequency range from 150 Hz to 500 Hz.

30. The structural panel of claim 28, wherein each one of said damping elements respectively comprises a cylindrical annular outer ring made of a metal or a fiber-reinforced composite material, an elastomer ring made of an elastomer material arranged within and bonded to said outer ring, and an inner member made of a metal or a fiber-reinforced composite material arranged within and bonded to said elastomer ring.