US4274039A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Servo-amplifier circuit
Assignee: FLUID DATA SYSTEMS
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Filing: 1980-02-25
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Granted: 1981-06-16
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Expires: 2000-02-25
Abstract
Abstract A circuit for a servo-amplifier saves power when the position servo has reached balance. The servo input is a high frequency differential transformer having its armature positioned by mechanical means driven by a servo motor controlled through amplifier circuitry. The power to the amplifier is turned off in the vicinity of the servo null point.
Inventors
- 👤 Gene Glassey
- 👤 Aldan D. Gomez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:32
CPC Classifications
G; G05; G05B; G05B11/00; G05B11/01; G05B5/00; G05B5/01
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
205 words
In a servo circuit of the type having a transducer, a differential amplifier for said transducer, a second amplifier, sources of + and - DC power for said second amplifier, the voltage output of said first amplifier controlling said second amplifier and a servo motor driven from said second amplifier, the improvement which comprises: a first resistor connected to the voltage output of said first amplifier and to a summing point, a non-linear gain characteristic third amplifier connected to the voltage output of said first amplifier, a second resistor of one-half the value of said first resistor connected to the output of said third amplifier and to said summing point, a source of reference currents connected to said summing point, a fourth amplifier receiving all of the signals at said summing point, off-on first switch means connected to said fourth amplifier operable only the voltage output of said fourth amplifier exceeds a pre-selected threshold level, a second switch between said source of + DC current and said second amplifier, and a third switch between said source of - DC current and said second amplifier, said first switch being arranged to open both said second and said third switches only when said first switch is operable.
Claim 2
Dependent Claim
205 words
In a servo circuit of the type having a transducer, a differential amplifier for said transducer, a second amplifier, sources of + and - DC power for said second amplifier, the voltage output of said first amplifier controlling said second amplifier and a servo motor driven from said second amplifier, the improvement which comprises: a first resistor connected to the voltage output of said first amplifier and to a summing point, a non-linear gain characteristic third amplifier connected to the voltage output of said first amplifier, a second resistor of one-half the value of said first resistor connected to the output of said third amplifier and to said summing point, a source of reference currents connected to said summing point, a fourth amplifier receiving all of the signals at said summing point, off-on first switch means connected to said fourth amplifier operable only the voltage output of said fourth amplifier exceeds a pre-selected threshold level, a second switch between said source of + DC current and said second amplifier, and a third switch between said source of - DC current and said second amplifier, said first switch being arranged to open both said second and said third switches only when said first switch is operable.
Claim 3
Dependent Claim
27 words
A circuit according to claim 1 in which said transducer is a differential transformer having an armature whose position is related to energization of said servo motor.
Claim 4
Dependent Claim
18 words
A circuit according to claim 2 in which said transformer is oscillated in the range of 20-40 KHz.
Claim 5
Dependent Claim
42 words
A circuit according to claim 1 which further comprises a potentiometer connected to said source of reference voltage operable to adjust the level of the output of said fourth amplifier and thereby to adjust the threshold of operation of said first switch.
Claim 6
Dependent Claim
15 words
A circuit according to claim 1 in which said first switch is a Schmitt trigger.
Claim 7
Dependent Claim
35 words
A circuit according to claim 1 which further comprises a generator driven by said servo motor, the output of said generator being fed back into said second amplifier to damp "hunting" of said servo motor.
Claim 8
Dependent Claim
37 words
A circuit according to claim 1 in which the output gain of said third amplifier is zero for all negative values at said summing point and a fixed voltage for all positive values at said summing point.
Claim 9
Dependent Claim
26 words
A circuit according to claim 1 in which the loss of performance of said circuit is essentially negligible compared with a fully live servo as contrasted.
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) | 1984-06-15 | 1984-12-15 | 1985-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-15 | 1988-12-15 | 1989-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-15 | 1992-12-15 | 1993-06-16 | $7700.00 | Window Closed / Lapsed |