US3723768A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semi-conductor devices
Assignee: English Electric Co Ltd
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Filing: 1966-01-12
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Granted: 1973-03-27
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Expires: 1986-01-12
Abstract
Abstract 1. A controlled-rectifier trigger circuit comprising, A PLURALITY OF CONTROLLED RECTIFIERS CONNECTED IN SERIES ACROSS AN A.C. SOURCE, EACH CONTROLLED RECTIFIER HAVING ANODE, CATHODE AND GATE ELECTRODES, A LIKE PLURALITY OF RADIATION-RESPONSIVE SWITCHING DEVICES, A CAPACITOR CONNECTED TO EACH SWITCHING DEVICE, MEANS CONNECTING A SAID SWITCHING DEVICE AND A CORRESPONDING ONE OF SAID CAPACITORS BETWEEN THE GATE AND CATHODE ELECTRODES OF EACH CONTROLLED RECTIFIER, A VOLTAGE DIVIDING NETWORK CONNECTED ACROSS SAID SOURCE, SAID NETWORK COMPRISING A. A SERIES CHAIN OF BI-DIRECTIONAL OR DOUBLE-CLIPPING ZENER DIODES, THREE OF SAID ZENER DIODES BEING ASSOCIATED WITH EACH CAPACITOR AND TWO OF THEM HAVING THE SAME OPERATING PARAMETERS, B. TWO LIKE-POLED UNCONTROLLED RECTIFIERS RESPECTIVELY CONNECTED IN SERIES WITH SAID TWO ZENER DIODES, AND C. MEANS CONNECTING EACH SAID UNCONTROLLED RECTIFIER, TOGETHER WITH ITS ASSOCIATED ZENER DIODE, IN PARALLEL WITH SAID CAPACITOR, AND RADIATION-EMITTING MEANS FOR PERIODICALLY ENERGIZING ALL SAID RADIATION-RESPONSIVE SWITCHING DEVICES SIMULTANEOUSLY WITH ONE ANOTHER WHEREBY TO ENABLE SAID RECTIFIERS TO BE TRIGGERED BY THE D.C. VOLTAGES DEVELOPED ACROSS THEIR ASSOCIATED CAPACITORS BY THE VOLTAGE DIVIDING NETWORK.
Inventors
- 👤 A Eccles
- 👤 N Potter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:47
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/08; H02M1/088; H02M1/092; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/725
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
173 words
A controlled-rectifier trigger circuit comprising, a plurality of controlled rectifiers connected in series across an a.c. source, each controlled rectifier having anode, cathode and gate electrodes, a like plurality of radiation-responsive switching devices, a capacitor connected to each switching device, means connecting a said switching device and a corresponding one of said capacitors between the gate and cathode electrodes of each controlled rectifier, a voltage dividing network connected across said source, said network comprising a. a series chain of bi-directional or double-clipping zener diodes, three of said zener diodes being associated with each capacitor and two of them having the same operating parameters, b. two like-poled uncontrolled rectifiers respectively connected in series with said two zener diodes, and c. means connecting each said uncontrolled rectifier, together with its associated zener diode, in parallel with said capacitor, and radiation-emitting means for periodically energizing all said radiation-responsive switching devices simultaneously with one another whereby to enable said rectifiers to be triggered by the d.c. voltages developed across their associated capacitors by the voltage dividing network.
Claim 2
Dependent Claim
173 words
A controlled-rectifier trigger circuit comprising, a plurality of controlled rectifiers connected in series across an a.c. source, each controlled rectifier having anode, cathode and gate electrodes, a like plurality of radiation-responsive switching devices, a capacitor connected to each switching device, means connecting a said switching device and a corresponding one of said capacitors between the gate and cathode electrodes of each controlled rectifier, a voltage dividing network connected across said source, said network comprising a. a series chain of bi-directional or double-clipping zener diodes, three of said zener diodes being associated with each capacitor and two of them having the same operating parameters, b. two like-poled uncontrolled rectifiers respectively connected in series with said two zener diodes, and c. means connecting each said uncontrolled rectifier, together with its associated zener diode, in parallel with said capacitor, and radiation-emitting means for periodically energizing all said radiation-responsive switching devices simultaneously with one another whereby to enable said rectifiers to be triggered by the d.c. voltages developed across their associated capacitors by the voltage dividing network.
Claim 3
Dependent Claim
138 words
In a chain of series-connected semiconductor controlled rectifiers having a voltAge divider connected in parallel to said rectifier chain, each rectifier having a control electrode and at least one main electrode and a firing circuit connected to the control electrode and one of the main electrodes of said rectifier on the one hand and on the other hand to two different points on the voltage divider, said firing circuit comprising means to derive a control voltage from the voltage between said points on the voltage divider and switching means for connecting said control voltage to the control electrode, thereby firing the rectifier, said means to derive a control voltage comprising a rectifying means connected to said points on the voltage divider and a capacitor connected to said rectifying means, said capacitor being also connected to said switching means.
Claim 4
Dependent Claim
138 words
In a chain of series-connected semiconductor controlled rectifiers having a voltAge divider connected in parallel to said rectifier chain, each rectifier having a control electrode and at least one main electrode and a firing circuit connected to the control electrode and one of the main electrodes of said rectifier on the one hand and on the other hand to two different points on the voltage divider, said firing circuit comprising means to derive a control voltage from the voltage between said points on the voltage divider and switching means for connecting said control voltage to the control electrode, thereby firing the rectifier, said means to derive a control voltage comprising a rectifying means connected to said points on the voltage divider and a capacitor connected to said rectifying means, said capacitor being also connected to said switching means.
Claim 5
Dependent Claim
35 words
A firing circuit according to claim 2, said rectifying means being a full-wave rectifying means having its AC terminals connected to said points of said voltage divider and its DC terminals connected to said capacitor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |