US4765436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dry friction damper with damping force perpendicular to principal direction of a vibration
Assignee: Duke University
•
Filing: 1986-12-10
•
Granted: 1988-08-23
•
Expires: 2006-12-10
Abstract
Abstract In a body subject to a cyclic energy of such a nature as to cause the body to mechanically vibrate with a principal motion in a first direction, a dry friction damper has a first sliding element fixed to the body, the first sliding element having a first rigid dry sliding surface extending in a second direction having a component perpendicular to the first direction. A second stationary element has a second rigid dry sliding surface extending in the second direction. A normal force is applied between the first and second surfaces, resulting in damping of vibrations by dry friction damping.
Inventors
- 👤 Earl H. Dowell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:19
CPC Classifications
F; F16; F16F; F16F7/00; F16F7/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
104 words
In a body subject to cyclic energy of such a nature as to cause said body to mechanically vibrate with a principal motion in a first direction, a dry friction vibration damping means comprising: a first sliding element fixed to said body and having a first rigid dry sliding surface extending in a second direction having a component perpendicular to said first direction; a second stationary, element having a second rigid surface engaging said first surface and extending in said second direction; and means for applying a normal force between said first and second surfaces, whereby said vibrations are damped by dry friction damping.
Claim 2
Dependent Claim
104 words
In a body subject to cyclic energy of such a nature as to cause said body to mechanically vibrate with a principal motion in a first direction, a dry friction vibration damping means comprising: a first sliding element fixed to said body and having a first rigid dry sliding surface extending in a second direction having a component perpendicular to said first direction; a second stationary, element having a second rigid surface engaging said first surface and extending in said second direction; and means for applying a normal force between said first and second surfaces, whereby said vibrations are damped by dry friction damping.
Claim 3
Dependent Claim
25 words
The body of claim 1, wherein said body is elongate and has a first end fixed relative to said stationary element and a second end.
Claim 4
Dependent Claim
16 words
The body of claim 1, wherein said second direction is substantially perpendicular to said first direction.
Claim 5
Dependent Claim
16 words
The body of claim 2, wherein said second direction is substantially perpendicular to said first direction.
Claim 6
Dependent Claim
21 words
The body of claim 2, wherein said body is a turbine blade and said second end of said body is unconstrained.
Claim 7
Dependent Claim
29 words
The body of claim 5, wherein said first sliding element comprises a spring, and wherein said means for applying a normal force comprises a spring force of said spring.
Claim 8
Dependent Claim
15 words
The body of claim 6, wherein said second direction is perpendicular to said first direction.
Claim 9
Dependent Claim
34 words
The body of claim 2, wherein said second direction has a horizontal component, and wherein said means for applying a normal force comprises the weight of at least said body and first sliding element.
Claim 10
Dependent Claim
41 words
The body of claim 8, wherein said second end is supported for constraint against translational movement except between said first and second surfaces, and for rotation about an axis transverse to said first direction and to the length of said body.
Claim 11
Dependent Claim
15 words
The body of claim 9, wherein said second direction is perpendicular to said first direction.
Claim 12
Dependent Claim
11 words
The body of claim 10, wherein said second direction is horizontal.
Claim 13
Dependent Claim
18 words
The body of claim 11, wherein said means for applying a normal force further comprises an additional weight.
References Cited (Backward Citations)
US1443545A
Cited
US2717747A
Cited
US2925973A
Cited
US3087565A
Cited
US3087569A
Cited
US3078969A
Cited
US3071217A
Cited
US3419260A
Cited
US4288063A
Cited
US4425980A
Cited
US4516658A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-08-23 | 1992-02-22 | 1992-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-23 | 1996-02-22 | 1996-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-23 | 2000-02-22 | 2000-08-23 | $7700.00 | Window Closed / Lapsed |