Patent US6217549B1 successfully refreshed from Google Patents.
US5924261A
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US
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Method and apparatus for damping structural vibrations
Assignee: Massachusetts Institute of Technology
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Filing: 1997-05-15
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Granted: 1999-07-20
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Expires: 2017-05-15
Abstract
Abstract The damped structural member includes a structural member and granular material in intimate contact with the member. In one embodiment the granular material is lightweight and has a bulk specific gravity of less than 1.5. When low weight is important, the granular material has a bulk specific gravity of less than or equal to one. The particles of the granular material are also in intimate contact with one another. The granular material may be substantially non-viscoelastic. Preferred granular material is low density polyethylene and glass microspheres. The granular material fills hollow structural members or is placed into intimate contact with open structural members. The lightweight fill effectively damps vibrational modes without excessively increasing the weight of the structural member.
Inventors
- 👤 J. Robert Fricke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:16
CPC Classifications
F; F16; F16F; F16F7/00; F16F7/01; F16F7/015; B; B64; B64G; B64G1/00; B64G1/22; B64G1/24; B64G1/38; E; E04; E04B; E04B1/00; E04B1/62; E04B1/92; E04B1/98; E04C; E04C3/00
Claims Analysis
Total Claims: 48
Claim 1
Independent Claim
42 words
Method for damping vibration in a structure comprising: placing nonspherical granular material into intimate contact with the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than one.
Claim 2
Dependent Claim
42 words
Method for damping vibration in a structure comprising: placing nonspherical granular material into intimate contact with the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than one.
Claim 3
Dependent Claim
12 words
The method of claim 1 wherein the material is low density polyethylene.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein the material is glass microspheres.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein the structure is a hollow member and the material fills the hollow member.
Claim 6
Dependent Claim
25 words
The method of claim 1 wherein the structure is an open beam and further comprising confining the granular material for contact with the open beam.
Claim 7
Dependent Claim
38 words
Damped structural member comprising: a structural member; and nonspherical granular material having a bulk specific gravity less than one in intimate contact with the member wherein particles of the granular material are in intimate contact with each other.
Claim 8
Dependent Claim
38 words
Damped structural member comprising: a structural member; and nonspherical granular material having a bulk specific gravity less than one in intimate contact with the member wherein particles of the granular material are in intimate contact with each other.
Claim 9
Dependent Claim
18 words
The structural member of claim 6 wherein the member is hollow and granular material fills the hollow member.
Claim 10
Dependent Claim
28 words
The structural member of claim 6 wherein the member is an open member and further including structure for maintaining the granular material in contact with the open member.
Claim 11
Dependent Claim
14 words
The structural member of claim 6 wherein the granular material is low density polyethylene.
Claim 12
Dependent Claim
13 words
The structural member of claim 6 wherein the granular material is glass microspheres.
Claim 13
Dependent Claim
39 words
Method for damping vibration in a structure comprising: coupling nonspherical granular material to the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than one.
Claim 14
Dependent Claim
39 words
Method for damping vibration in a structure comprising: coupling nonspherical granular material to the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than one.
Claim 15
Dependent Claim
34 words
Method for damping vibration in a structure comprising: coupling nonspherical granular material to the structure wherein particles of the granular material are in intimate contact with each other, the granular material being substantially non-viscoelastic.
Claim 16
Dependent Claim
34 words
Method for damping vibration in a structure comprising: coupling nonspherical granular material to the structure wherein particles of the granular material are in intimate contact with each other, the granular material being substantially non-viscoelastic.
Claim 17
Dependent Claim
14 words
The method of claim 11 or claim 12 wherein the structure is a beam.
Claim 18
Dependent Claim
15 words
The method of claim 11 or claim 12 wherein the structure is an enclosed beam.
Claim 19
Dependent Claim
19 words
The method of claim 11 or claim 12 wherein the structure is excited at at least one drive point.
Claim 20
Dependent Claim
18 words
The method of claim 11 or claim 12 wherein the structure is a beam with members attached thereto.
Claim 21
Dependent Claim
36 words
Damped structural member comprising: a structural member; and nonspherical granular material having a bulk specific gravity less than one coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 22
Dependent Claim
36 words
Damped structural member comprising: a structural member; and nonspherical granular material having a bulk specific gravity less than one coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 23
Dependent Claim
30 words
Damped structural member comprising: a structural member; and nonspherical granular, substantially non-viscoelastic material coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 24
Dependent Claim
30 words
Damped structural member comprising: a structural member; and nonspherical granular, substantially non-viscoelastic material coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 25
Dependent Claim
16 words
The damped structural member of claim 17 or claim 18 wherein the member is a beam.
Claim 26
Dependent Claim
17 words
The damped structural member of claim 17 or claim 18 wherein the member is an enclosed beam.
Claim 27
Dependent Claim
21 words
The damped structural member of claim 17 or claim 18 wherein the member is excited at at least one drive point.
Claim 28
Dependent Claim
20 words
The damped structural member of claim 17 or claim 18 wherein the member is a beam with members attached thereto.
Claim 29
Dependent Claim
42 words
Method for damping vibration in a structure comprising: placing nonspherical granular material into intimate contact with the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than 1.5.
Claim 30
Dependent Claim
42 words
Method for damping vibration in a structure comprising: placing nonspherical granular material into intimate contact with the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than 1.5.
Claim 31
Dependent Claim
38 words
Damped structural member comprising: a structural member; and nonspherical granular material having a bulk specific gravity less than 1.5 in intimate contact with the member wherein particles of the granular material are in intimate contact with each other.
Claim 32
Dependent Claim
38 words
Damped structural member comprising: a structural member; and nonspherical granular material having a bulk specific gravity less than 1.5 in intimate contact with the member wherein particles of the granular material are in intimate contact with each other.
Claim 33
Dependent Claim
42 words
Method for damping vibration in a structure comprising: coupling granular material composed of nonsolid granules to the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than 1.5.
Claim 34
Dependent Claim
42 words
Method for damping vibration in a structure comprising: coupling granular material composed of nonsolid granules to the structure wherein particles of the granular material are in intimate contact with each other, the granular material having a bulk specific gravity less than 1.5.
Claim 35
Dependent Claim
38 words
Method for damping vibration in a structure comprising: coupling granular glass to the structure wherein particles of the granular glass are in intimate contact with each other, the granular glass having a bulk specific gravity less than 1.5.
Claim 36
Dependent Claim
38 words
Method for damping vibration in a structure comprising: coupling granular glass to the structure wherein particles of the granular glass are in intimate contact with each other, the granular glass having a bulk specific gravity less than 1.5.
Claim 37
Dependent Claim
37 words
Method for damping vibration in a structure comprising: coupling granular material composed of nonsolid granules to the structure wherein particles of the granular material are in intimate contact with each other, the granular material being substantially non-viscoelastic.
Claim 38
Dependent Claim
37 words
Method for damping vibration in a structure comprising: coupling granular material composed of nonsolid granules to the structure wherein particles of the granular material are in intimate contact with each other, the granular material being substantially non-viscoelastic.
Claim 39
Dependent Claim
33 words
Method for damping vibration in a structure comprising: coupling granular glass to the structure wherein particles of the granular material are in intimate contact with each other, the granular glass being substantially non-viscoelastic.
Claim 40
Dependent Claim
33 words
Method for damping vibration in a structure comprising: coupling granular glass to the structure wherein particles of the granular material are in intimate contact with each other, the granular glass being substantially non-viscoelastic.
Claim 41
Dependent Claim
39 words
Damped structural member comprising: a structural member; and granular material composed of nonsolid granules having a bulk specific gravity less than 1.5 coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 42
Dependent Claim
39 words
Damped structural member comprising: a structural member; and granular material composed of nonsolid granules having a bulk specific gravity less than 1.5 coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 43
Dependent Claim
35 words
Damped structural member comprising: a structural member; and granular glass having a bulk specific gravity less than 1.5 coupled to the member wherein particles of the granular glass are in intimate contact with each other.
Claim 44
Dependent Claim
35 words
Damped structural member comprising: a structural member; and granular glass having a bulk specific gravity less than 1.5 coupled to the member wherein particles of the granular glass are in intimate contact with each other.
Claim 45
Dependent Claim
33 words
Damped structural member comprising: a structural member; and granular material composed of substantially non-viscoelastic nonsolid granules coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 46
Dependent Claim
33 words
Damped structural member comprising: a structural member; and granular material composed of substantially non-viscoelastic nonsolid granules coupled to the member wherein particles of the granular material are in intimate contact with each other.
Claim 47
Dependent Claim
30 words
Damped structural member comprising: a structural member; and substantially non-viscoelastic granular glass coupled to the member wherein the particles of the granular glass are in intimate contact with each other.
Claim 48
Dependent Claim
30 words
Damped structural member comprising: a structural member; and substantially non-viscoelastic granular glass coupled to the member wherein the particles of the granular glass are in intimate contact with each other.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-07-19 | 2003-01-18 | 2003-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-07-19 | 2007-01-18 | 2007-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-07-19 | 2011-01-18 | 2011-07-20 | $7700.00 | Window Closed / Lapsed |