US4199989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cold damping of mechanical structures
Assignee: Raytheon Co
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Filing: 1978-09-18
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Granted: 1980-04-29
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Expires: 1998-09-18
Abstract
Abstract Methods and apparatus are disclosed for substantially reducing the effect of the inherent transducer capacitance in a transducer-coupled electromechanical system which is subject to vibrational movement. First and second electromechanical transducers, mechanically coupled to the mechanical structure are interconnected by an electronic feedback network. The feedback network is characterized by very low input and output impedances thus overcoming the shunting effects of the inherent transducer capacitance. In preferred embodiments the feedback network is "electronically cooled" thereby providing low-noise damping.
Inventors
- 👤 Robert L. Forward
- 👤 Robert W. Peterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:36
CPC Classifications
F; F16; F16F; F16F15/00; F16F15/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
106 words
In an electromechanical system including a mechanical member which is subject to vibrational movement, first and second electromechanical transducers mounted on said member, said first electromechanical transducer being capable of providing an electrical charge having a rate of change proportional to the velocity of said mechanical member, said second electromechanical transducer being capable of imparting a motion to said member in response to an electrical voltage applied thereto, circuit means being connected between said first and second transducers said circuit means including a current-to-voltage transducer, said current-to-voltage transducer comprising a differential-input operational amplifier operating in the current input mode and having a low noise-temperature feedback circuit.
Claim 2
Dependent Claim
106 words
In an electromechanical system including a mechanical member which is subject to vibrational movement, first and second electromechanical transducers mounted on said member, said first electromechanical transducer being capable of providing an electrical charge having a rate of change proportional to the velocity of said mechanical member, said second electromechanical transducer being capable of imparting a motion to said member in response to an electrical voltage applied thereto, circuit means being connected between said first and second transducers said circuit means including a current-to-voltage transducer, said current-to-voltage transducer comprising a differential-input operational amplifier operating in the current input mode and having a low noise-temperature feedback circuit.
Claim 3
Dependent Claim
22 words
The system according to claim 1 wherein said first and second electromechanical transducers are connected electrically in series and mechanically in parallel.
Claim 4
Dependent Claim
31 words
The system according to claim 1 wherein the input impedance of said current-to-voltage transducer is substantially less than equivalent capacitive reactance of said first electromechanical transducer over the frequencies of operation.
Claim 5
Dependent Claim
16 words
The system according to claim 1 wherein said feedback network includes a second differential-input operational amplifier.
Claim 6
Dependent Claim
103 words
In an electromechanical system including a mechanical member which is subject to vibrational movement, first and second electromechanical transducers mounted on said member, said first electromechanical transducer being capable of generating an electrical charge having a charge rate of change proportional to the velocity of said mechanical member, said second electromechanical transducer being capable of imparting a motion to said member in response to an electrical voltage applied thereto, circuit means being connected between said first and second transducers said circuit means including a differential-input operational amplifier operating in the current input mode and including a feedback network which simulates a low-temperature resistor.
Claim 7
Dependent Claim
103 words
In an electromechanical system including a mechanical member which is subject to vibrational movement, first and second electromechanical transducers mounted on said member, said first electromechanical transducer being capable of generating an electrical charge having a charge rate of change proportional to the velocity of said mechanical member, said second electromechanical transducer being capable of imparting a motion to said member in response to an electrical voltage applied thereto, circuit means being connected between said first and second transducers said circuit means including a differential-input operational amplifier operating in the current input mode and including a feedback network which simulates a low-temperature resistor.
Claim 8
Dependent Claim
22 words
The system according to claim 5 wherein said first and second electromechanical transducers are connected electrically in series and mechanically in parallel.
Claim 9
Dependent Claim
32 words
The system according to claim 5 wherein the input impedance of said operational amplifier is substantially less than the equivalent capacitive reactance of said first electromechanical transducer over the frequencies of operation.
Claim 10
Dependent Claim
16 words
The system according to claim 5 wherein said feedback network includes a second differential-input operational amplifier.
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) | 1983-04-29 | 1983-10-29 | 1984-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-29 | 1987-10-29 | 1988-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-29 | 1991-10-29 | 1992-04-29 | $7700.00 | Window Closed / Lapsed |