Patent US4954375A successfully refreshed from Google Patents.
US4954375A
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Vibration damping apparatus
Assignee: Northrop Grumman Corp
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Filing: 1988-12-29
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Granted: 1990-09-04
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Expires: 2008-12-29
Abstract
Abstract A hollow beam structure such as a machinery subbase having apertures in sidewall portions thereof has a plurality of shear damper assemblies which straddle the apertures and are fastened to the wall portion on opposite sides of the apertures. The shear damper assemblies include a viscoelectric damping layer which dissipates vibrational energy to minimize the vibrational response of the hollow beam structure.
Inventors
- 👤 Stanley S. Sattinger
- 👤 Leo K. H. Lu
- 👤 Jerry R. Smerecky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:28
CPC Classifications
F; F16; F16M; F16M5/00; F16F; F16F9/00; F16F9/30; F16F9/306; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/139
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
104 words
A vibrationally damped structure, comprising: A) a hollow beam structure having a plurality of wall portions; B) at least one of said wall portions including a plurality of apertures therethrough; C) a plurality of shear damping assemblies operable to absorb energy from unwanted vibrational excitation, with each said shear damping assembly including a plurality of plate members and which extends across a respective one of said apertures with a first said plate member being secured to said wall portion on one side of said aperture and a second said plate members being secured to said wall portion on an opposite side of said aperture.
Claim 2
Dependent Claim
104 words
A vibrationally damped structure, comprising: A) a hollow beam structure having a plurality of wall portions; B) at least one of said wall portions including a plurality of apertures therethrough; C) a plurality of shear damping assemblies operable to absorb energy from unwanted vibrational excitation, with each said shear damping assembly including a plurality of plate members and which extends across a respective one of said apertures with a first said plate member being secured to said wall portion on one side of said aperture and a second said plate members being secured to said wall portion on an opposite side of said aperture.
Claim 3
Dependent Claim
53 words
The structure according to claim 1 wherein said first and second plate members in each said damping assembly are generally coplanar and there is a third plate member which overlaps said first and second members, with a viscoelastic damping layer sandwiched between said third plate member and said first and second plate members.
Claim 4
Dependent Claim
17 words
The structure according to claim 2 wherein: A) said hollow beam structure has a rectangular cross section.
Claim 5
Dependent Claim
43 words
The structure according to claim 2 wherein: A) said hollow beam structure forms a portion of a machinery subbase which includes a plurality of said hollow beam structures arranged in a plurality of leg segments to support a machine which generates vibrational energy.
Claim 6
Dependent Claim
29 words
The structure according to claim 2 wherein: A) said third plate of said shear damper assembly is disposed within the aperture across which each said shear damper assembly extends.
Claim 7
Dependent Claim
36 words
The structure according to claim 1 wherein said second plate member in each said damping assembly overlaps said first plate member, and there is a viscoelastic damping layer sandwhiched between said first and second plate members.
Claim 8
Dependent Claim
17 words
The structure according to claim 6 wherein: A) said hollow beam structure has a rectangular cross section.
Claim 9
Dependent Claim
43 words
The structure according to claim 6 wherein: A) said hollow beam structure forms a portion of a machinery subbase which includes a plurality of said hollow beam structures arranged in a plurality of leg segments to support a machine which generates vibrational energy.
Claim 10
Dependent Claim
30 words
The structure according to claims 2 or 6 wherein: A) said plate members are relatively narrow such that each said shear damping assembly is in the form of a strut.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-03 | 1994-03-05 | 1994-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-03 | 1998-03-05 | 1998-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-03 | 2002-03-05 | 2002-09-04 | $7700.00 | Window Closed / Lapsed |