Patent US3274474A successfully refreshed from Google Patents.
US3274474A
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Controlled rectifier supply for motor speed system
Assignee: POWER ENGINEERING Inc
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Filing: 1963-09-03
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Granted: 1966-09-20
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Expires: 1983-09-03
Abstract
No abstract record available.
Inventors
- 👤 Ronald C Dow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:40
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/921
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
150 words
A POLYSPEED VARIABLE MOTOR DRIVE FROM A UNIDIRECTIONAL CURRENT SOURCE WHICH COMPRISES: (A) A FIRST CIRCUIT INCLUDING A FIELD WINDING CONNECTED ACROSS SAID SOURCE, (B) A SECOND CIRCUIT INCLUDING A CONTROLLED RECTIFIER IN SERIES WITH THE ARMATURE OF SAID MOTOR CONNECTED ACROSS SAID SOURCE, (C) A THIRD CIRCUIT CONNECTED ACROSS SAID SOURCE AND TO SAID FIRST CONTROLLED RECTIFIER AND INCLUDING TIMING MEANS TO RENDER SAID RECTIFIER CONDUCTIVE AT TIME INTERVALS DEPENDENT UPON THE SETTING OF SAID TIMING MEANS, (D) A FOURTH CIRCUIT CONNECTED ACROSS SAID SOURCE INCLUDING A SECOND CONTROLLED RECTIFIER POLED THE SAME AS SAID FIRST CONTROLLED RECTIFIER AND CONNECTED IN SERIES WITH A PAIR OF NORMALLY CLOSED RELAY CONTACTS AND A RESISTOR, (E) A CONDENSER CONNECTED AT ONE TERMINAL TO THE JUNCTURE BETWEEN THE FIRST CONTROLLED RECTIFIER AND SAID ARMATURE AND AT THE OTHER TERMINAL TO THE JUNCTURE BETWEEN THE SECOND CONTROLLED RECTIFIER AND SAID NORMALLY CLOSED CONTACTS,
References Cited (Backward Citations)
US3150307A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-09-19 | 1970-03-21 | 1970-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-19 | 1974-03-21 | 1974-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-19 | 1978-03-21 | 1978-09-20 | $7700.00 | Window Closed / Lapsed |