US3577646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of damping devices having oscillatory motion
Assignee: BAE Systems Aircraft Controls Inc
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Filing: 1967-11-30
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Granted: 1971-05-04
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Expires: 1987-11-30
Abstract
Abstract A method for damping an oscillating mechanical system to bring it to rest at or near its equilibrium position employing iteratively a fixed damping cycle consisting of a first interval of undamped motion followed by a second interval of supercritically damped motion, the process being iterated a sufficient number of cycles to position the system as close as desired to the equilibrium position. A preferred application of this method of damping is in connection with a meridian-seeking gyroscope, where the first interval of undamped motion consists of free precession of the gyroscope pin axle toward the meridional plane, followed by a second interval of supercritical damping that positions the spin axle closer to the meridional plane than at the release of the motion. By repeating the appropriately timed intervals of the cycle a number of times, the spin axle of the meridian-seeking gyroscope can be brought as close to the meridional plane as desired.
Inventors
- 👤 Harry Nils Eklund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:06
CPC Classifications
F; F16; F16F; F16F15/00; F16F15/02; Y; Y10; Y10T; Y10T74/00; Y10T74/12; Y10T74/1229; Y10T74/1257
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
99 words
A method of damping the motion of a mechanical system element which is oscillating about an equilibrium position, the motion of the element having a substantially undamped natural period of oscillation, the method comprising the step of applying supercritical damping force to the element for a selected interval of time commencing from when the ratio of the instantaneous velocity of the element toward its equilibrium position to the instantaneous displacement of the element from its equilibrium position is approximately equal to the ratio of pi to the product of the undamped natural period of oscillation and the damping ratio.
Claim 2
Independent Claim
99 words
A method of damping the motion of a mechanical system element which is oscillating about an equilibrium position, the motion of the element having a substantially undamped natural period of oscillation, the method comprising the step of applying supercritical damping force to the element for a selected interval of time commencing from when the ratio of the instantaneous velocity of the element toward its equilibrium position to the instantaneous displacement of the element from its equilibrium position is approximately equal to the ratio of pi to the product of the undamped natural period of oscillation and the damping ratio.
Claim 3
Dependent Claim
30 words
A method in accordance with claim 1 including the additional steps of repeating the step a selected number of times so as to further damp the motion of the element.
Claim 4
Dependent Claim
54 words
The method in accordance with claim 1 wherein the selected interval of time, t, is given by the expression undamped period, o is the initial displacement from the equilibrium position, psi is the displacement from the equilibrium position at the end of said selected interval of time, and delta is the supercritical damping ratio.
Claim 5
Dependent Claim
21 words
The method in accordance with claim 1 wherein the supercritical damping force is proportional to the velocity of the moving element.
Claim 6
Dependent Claim
24 words
The method in accordance with claim 1 wherein the supercritical damping force is proportional to the square of the velocity of the moving element.
Claim 7
Dependent Claim
22 words
The method in accordance with claim 1 wherein the supercritical damping force is a function of the velocity of the moving element.
Claim 8
Dependent Claim
15 words
A method in accordance with claim 1 wherein the supercritical damping ratio is approximately 10.
Claim 9
Dependent Claim
17 words
A method in accordance with claim 1 wherein the supercritical damping ratio is between 5 and 20.
Claim 10
Dependent Claim
59 words
The method of damping in accordance with claim 1 including in addition a first inItial step of applying supercritical damping force to the element for a selected interval of time and a second initial step of removing the supercritical damping force thereby allowing the element to move undamped until supercritical damping force is reapplied in accordance with claim 1.
Claim 11
Dependent Claim
60 words
The method in accordance with claim 9 wherein the time at which the supercritical damping force is removed precedes the time at which supercritical damping force is reapplied by an amount which is approximately equal to the quantity t, where t is given by the expression where delta is the supercritical damping ratio and T is the undamped natural period.
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) | 1974-05-03 | 1974-11-02 | 1975-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-03 | 1978-11-02 | 1979-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-03 | 1982-11-02 | 1983-05-04 | $7700.00 | Window Closed / Lapsed |