US3817356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vibration damping
Assignee: 3M Co
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Filing: 1973-05-29
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Granted: 1974-06-18
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Expires: 1993-05-29
Abstract
Abstract A method of damping vibrations in a steel panel which is subject to destructive or annoying vibrations. A vibration damping sandwich comprising a sheet of a flexible magnetic material and a flexible ferromagnetic sheet coextensive with one face of the flexible magnetic sheet is placed with the exposed face of the magnetic sheet against the steel panel to cover at least onetenth of the surface area of the panel. The damping sandwich has sufficient flexibility and magnetic strength to conform to the steel panel and to maintain intimate contact therewith to damp vibrations in the panel through frictional sliding between the panel and the layers of the damping sandwich and within the damping sandwich.
Inventors
- 👤 C Dahlquist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 00:14
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/30; F16F9/306; B; B32; B32B; B32B5/00; B32B5/16; B32B15/00; B32B15/01; B32B15/16; B32B15/18; B32B7/00; B32B7/04; B32B7/12; F16F15/00; F16F15/02; F16F15/03; G; G10; G10K; G10K11/00; G10K11/16; B32B2307/00; B32B2307/20; B32B2307/208; B32B2307/50; B32B2307/56; B32B2311/00; B32B2311/30; B32B2607/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
177 words
A method of damping vibrations in a steel panel which is subject to destructive or annoying vibrations and which has a thickness X and an area Y, comprising the steps of: providing a vibration damping sandwich comprising a sheet of a flexible magnetic material having a major proportion of permanent magnet particles in an organic binder, said flexible magnetic material having a coefficient of friction with steel of at least 0.3, a BHmax of at least 0.5 X 106 gauss-oersteds and a thickness of 0.01 inch to 0.5 inch, and a flexible ferromagnetic sheet coextensive with one face of said flexible magnetic sheet and having a thickness 4 percent to 40 percent that of the magnetic sheet but not greater than 0.6X, said vibration damping sandwich having sufficient flexibility to conform to the steel panel and to maintain intimate contact therewith, and placing at least one piece of said vibration damping sandwich with the exposed face of said magnetic sheet against the steel panel to cover at least 0.1 Y to damp vibrations in the steel panel.
Claim 2
Independent Claim
177 words
A method of damping vibrations in a steel panel which is subject to destructive or annoying vibrations and which has a thickness X and an area Y, comprising the steps of: providing a vibration damping sandwich comprising a sheet of a flexible magnetic material having a major proportion of permanent magnet particles in an organic binder, said flexible magnetic material having a coefficient of friction with steel of at least 0.3, a BHmax of at least 0.5 X 106 gauss-oersteds and a thickness of 0.01 inch to 0.5 inch, and a flexible ferromagnetic sheet coextensive with one face of said flexible magnetic sheet and having a thickness 4 percent to 40 percent that of the magnetic sheet but not greater than 0.6X, said vibration damping sandwich having sufficient flexibility to conform to the steel panel and to maintain intimate contact therewith, and placing at least one piece of said vibration damping sandwich with the exposed face of said magnetic sheet against the steel panel to cover at least 0.1 Y to damp vibrations in the steel panel.
Claim 3
Dependent Claim
43 words
The method of claim 1 including the step of rigidly securing said vibration damping sandwich to said steel panel at least at one point to maximize the average displacement between the sandwich and the steel panel and between the layers of the sandwich.
Claim 4
Dependent Claim
56 words
The method of claim 1 including the steps of providing a second vibration damping sandwich as defined in claim 1 and placing at least one piece of said second vibration damping sandwich with the exposed face of its magnetic sheet against and within the periphery of the flexible ferromagnetic sheet of said first vibration damping sandwich.
Claim 5
Dependent Claim
40 words
The method of claim 1 wherein said step of placing at least one piece of said vibration damping sandwich comprises placing at least one piece of said vibration damping sandwich against the steel panel to cover a plurality of antinodes.
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) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |