US3737736A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnet-controlling system
Assignee: Lucifer SA
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Filing: 1972-04-04
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Granted: 1973-06-05
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Expires: 1992-04-04
Abstract
Abstract An arrangement for feeding the power winding of an electromagnet with rectified A.C. by means of a thyristor or triac. The latter is inserted in parallel with a transistor the conducting condition of which is provided by a condenser fed by the rectified A.C. and discharging into the base of the transistor which latter acts then on the electrode controlling the thyristor, to allow the latter to return into its non-conductive condition at the end of an alternation. A maintenance or holding current is provided either through an auxiliary electromagnet winding or through a chopped current feeding the power winding and produced by a pulse generator.
Inventors
- 👤 H Stampfli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:38
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/73; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/18; H01F7/1805; H01F7/1833; H03K17/60; H03K17/64; F; F02; F02D; F02D41/00; F02D41/20; F02D2041/2068; F02D2041/2079
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
100 words
An electromagnet-controlling system adapted to produce a strong starting current for an electromagnet power winding followed by a weaker holding current comprising a Graetz rectifier, adaptEd to be fed with A.C., a thyristor circuit including an anode and a cathode inserted in series between the rectifier and the electromagnet power winding and a controlling electrode, and delaying means inserted between said cathode and controlling electrode and adapted to become conductive at a predetermined moment after energization of the rectifier to allow the thyristor circuit to return to its inoperative condition and means feeding a weaker holding current to the electromagnet.
Claim 2
Dependent Claim
100 words
An electromagnet-controlling system adapted to produce a strong starting current for an electromagnet power winding followed by a weaker holding current comprising a Graetz rectifier, adaptEd to be fed with A.C., a thyristor circuit including an anode and a cathode inserted in series between the rectifier and the electromagnet power winding and a controlling electrode, and delaying means inserted between said cathode and controlling electrode and adapted to become conductive at a predetermined moment after energization of the rectifier to allow the thyristor circuit to return to its inoperative condition and means feeding a weaker holding current to the electromagnet.
Claim 3
Dependent Claim
74 words
A system as claimed in claim 1, wherein the delaying means include a transistor, the emitter-collector circuit of which is inserted in parallel with the thyristor circuit and is connected with the controlling resistance of the latter, a resistance and condenser circuit fed by the rectifier and an element provided with a threshold voltage and operatively connecting said condenser with the transistor base as soon as the condenser voltage has reached a predetermined voltage.
Claim 4
Dependent Claim
107 words
A system as claimed in claim 1, wherein the delaying means include a transistor, the emitter-collector circuit of which is inserted in parallel with the thyristor circuit and is connected with the controlling resistance of the latter, a resistance and condenser circuit fed by the rectifier and an element provided with a threshold voltage and operatively connecting said condenser with the transistor base as soon as the condenser voltage has reached a predetermined voltage, and at least one diode inserted between the negative terminal of the rectifier and the cathode of the thyristor circuit and leading the current passing out of the latter towards said negative terminal.
Claim 5
Dependent Claim
33 words
A system as claimed in claim 1, wherein the means feeding the holding current include an auxiliary holding winding inserted across the rectifier terminals in parallel with the power winding and thyristor circuit.
Claim 6
Dependent Claim
113 words
A system as claimed in claim 1, wherein the delaying means include a transistor, the emitter-collector circuit of which is inserted in parallel with the thyristor circuit and is connected with the controlling resistance of the latter, a resistance and condenser circuit fed by the rectifier and an element provided with a threshold voltage and operatively connecting said condenser with the transistor base as soon as the condenser voltage has reached a predetermined voltage and wherein the means feeding the holding current include a generator of pulses synchronized with the frequency of the A.C. fed to the rectifier and phase-shifted with reference thereto and means for applying said pulses to the thyristor circuit.
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) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |