Patent US3355640A successfully refreshed from Google Patents.
US3355640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bi-directional electrical servo system
Assignee: CHAMPLAIN CO Inc
•
Filing: 1964-01-16
•
Granted: 1967-11-28
•
Expires: 1984-01-16
Abstract
No abstract record available.
Inventors
- 👤 Clarence A Lewis
- 👤 James F O'brien
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:34
CPC Classifications
B; B65; B65H; B65H23/00; B65H23/04; B65H23/18; B65H23/188; B65H23/1882; G; G05; G05D; G05D3/00; G05D3/12; G05D3/14; G05D3/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
134 words
A SERVO SYSTEM COMPRISING A DC SERVO MOTOR TO MOVE A LOAD, AN AC POWER SOURCE CONNECTED THROUGH EITHER OF TWO OPPOSITELY POLARIZED SILICON CONTROLLED RECTIFIERS TO THE ARMATURE OF SAID MOTOR, A SYNCHRONOUS PULSE SOURCE HAVING A FREQUENCY WHICH IS DOUBLE THAT OF THE AC POWER SOURCE, MEANS TO SUPPLY AN ERROR SIGNAL, SAID MOTOR ARMATURE BEING USED TO SUPPLY AN OUTPUT RATE FEEDBACK, MEANS TO RECEIVE AND TO COMPARE THE ERROR SIGNAL AND THE FEEDBACK, AND MEANS RESPONSIVE TO AN EXCESS OF ERROR SIGNAL OVER FEEDBACK TO SUPPLY THE DOUBLE FREQUENCY PULSE TO THE GATE LEAD OF ONE SILICON CONTROLLED RECTIFIER OR THE OTHER IN ORDER TO SUPPLY A TRAIN OF SUBSTANTIALLY FULL WIDTH ALTERNATE AND THEREFORE UNIDIRECTIONAL HALF WAVES WHICH TURNS THE MOTOR IN THAT DIRECTION WHICH LESSENS THE ERROR SIGNAL.
Claim 2
Dependent Claim
134 words
A SERVO SYSTEM COMPRISING A DC SERVO MOTOR TO MOVE A LOAD, AN AC POWER SOURCE CONNECTED THROUGH EITHER OF TWO OPPOSITELY POLARIZED SILICON CONTROLLED RECTIFIERS TO THE ARMATURE OF SAID MOTOR, A SYNCHRONOUS PULSE SOURCE HAVING A FREQUENCY WHICH IS DOUBLE THAT OF THE AC POWER SOURCE, MEANS TO SUPPLY AN ERROR SIGNAL, SAID MOTOR ARMATURE BEING USED TO SUPPLY AN OUTPUT RATE FEEDBACK, MEANS TO RECEIVE AND TO COMPARE THE ERROR SIGNAL AND THE FEEDBACK, AND MEANS RESPONSIVE TO AN EXCESS OF ERROR SIGNAL OVER FEEDBACK TO SUPPLY THE DOUBLE FREQUENCY PULSE TO THE GATE LEAD OF ONE SILICON CONTROLLED RECTIFIER OR THE OTHER IN ORDER TO SUPPLY A TRAIN OF SUBSTANTIALLY FULL WIDTH ALTERNATE AND THEREFORE UNIDIRECTIONAL HALF WAVES WHICH TURNS THE MOTOR IN THAT DIRECTION WHICH LESSENS THE ERROR SIGNAL.
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) | 1970-11-27 | 1971-05-29 | 1971-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-11-27 | 1975-05-29 | 1975-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-11-27 | 1979-05-29 | 1979-11-28 | $7700.00 | Window Closed / Lapsed |