Patent US4041775A successfully refreshed from Google Patents.
US4041775A
Expired / Lapsed
US
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Vibrometer
Assignee: RCA Corp
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Filing: 1975-03-27
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Granted: 1977-08-16
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Expires: 1995-03-27
Abstract
Abstract A plurality of circular cross section elongated vibrometer reeds each having a predetermined frequency response to a vibration in a given plane are secured to a vibration transmission medium in predetermined orientations. The medium is secured in vibrating communication with a machine frame, for example, a helicopter frame, to transmit frame vibrations to the reeds. Each reed is oriented to respond to at least one vibration associated with a known source of vibration in an environment of complex vibrations produced by a plurality of sources in the machine.
Inventors
- 👤 James Arthur McNamee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:42
CPC Classifications
G; G01; G01H; G01H1/00; G01H1/04; G01H1/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
101 words
The combination of a helicopter and a system secured thereto for indicating the vibrating modes of the various rotors of the helicopter comprising, in combination: a plurality of vibration detectors each secured to the frame of the helicopter, each detector being positioned, dimensioned and secured to the frame in such a way as to be actuated substantially only by a particular vibratory mode of a particular rotor and to be substantially unaffected by vibratory modes of the other rotors; and indicator means for indicating the modes of vibration of the respective detectors for in turn indicating fault conditions of the rotors.
Claim 2
Dependent Claim
101 words
The combination of a helicopter and a system secured thereto for indicating the vibrating modes of the various rotors of the helicopter comprising, in combination: a plurality of vibration detectors each secured to the frame of the helicopter, each detector being positioned, dimensioned and secured to the frame in such a way as to be actuated substantially only by a particular vibratory mode of a particular rotor and to be substantially unaffected by vibratory modes of the other rotors; and indicator means for indicating the modes of vibration of the respective detectors for in turn indicating fault conditions of the rotors.
Claim 3
Independent Claim
52 words
A method of testing, in flight, or on the ground the rotors of a helicopter comprising the steps of: concurrently and individually measuring the amplitudes and modes of vibration of the respctive rotors of the helicopter; and indicating, in response to the measurements, different fault vibratory conditions for each of the rotors.
Claim 4
Independent Claim
52 words
A method of testing, in flight, or on the ground the rotors of a helicopter comprising the steps of: concurrently and individually measuring the amplitudes and modes of vibration of the respctive rotors of the helicopter; and indicating, in response to the measurements, different fault vibratory conditions for each of the rotors.
References Cited (Backward Citations)
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US2428671A
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US2906117A
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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) | 1980-08-15 | 1981-02-14 | 1981-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-15 | 1985-02-14 | 1985-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-15 | 1989-02-14 | 1989-08-16 | $7700.00 | Window Closed / Lapsed |