US3784890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulse control circuit for a dc load
Assignee: Allis Chalmers Corp
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Filing: 1972-12-12
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Granted: 1974-01-08
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Expires: 1992-12-12
Abstract
Abstract A circuit for providing controlled pulses of direct current to vary the speed of a direct current motor. A main controlled rectifier applies current to the motor. A commutation circuit consisting of an inductor, a capacitor and another controlled rectifier turns off the main controlled rectifier by reversing its polarity. Another circuit, referred to as a ''''ring-around'''' circuit, consisting of another inductor and controlled rectifier reverses the polarity of the commutating capacitor preparatory to the commutation of the main controlled rectifier.
Inventors
- 👤 A Geiersbach
- 👤 R Price
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:54
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/125; H02M3/135; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/917
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
90 words
A control system for a direct current operated load comprising; a first controlled rectifier connected in series between a terminal of the load and the direct current source; second and third controlled rectifiers and first and second inductors all connected in series with said load and across said first controlled rectifier; a capacitor connected in parallel with said second controlled rectifier and said first inductor and in series with said third controlled rectifier, said second inductor, and said load; and gating signal sources connected to each of said controlled rectifiers.
Claim 2
Dependent Claim
90 words
A control system for a direct current operated load comprising; a first controlled rectifier connected in series between a terminal of the load and the direct current source; second and third controlled rectifiers and first and second inductors all connected in series with said load and across said first controlled rectifier; a capacitor connected in parallel with said second controlled rectifier and said first inductor and in series with said third controlled rectifier, said second inductor, and said load; and gating signal sources connected to each of said controlled rectifiers.
Claim 3
Dependent Claim
42 words
The control system set forth in claim 1 wherein said direct current load is an electric motor and further comprising a rectifier diode connected across the motor to permit motor current to flow during the off period of said first controlled rectifier.
Claim 4
Dependent Claim
16 words
The control system set forth in claim 1 wherein said controlled rectifiers are silicon controlled rectifiers.
Claim 5
Dependent Claim
16 words
The control system set forth in claim 2 wherein said controlled rectifiers are silicon controlled rectifiers.
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) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |