US3735158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Three terminal bidirectional conductive switching network
Assignee: Boeing Co
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Filing: 1972-06-19
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Granted: 1973-05-22
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Expires: 1992-06-19
Abstract
Abstract A three terminal network having first and second load terminals for connection in series circuit relationship with a load across a pair of power supply terminals, and a third gating terminal for controlling alternating current flow in the load. The present three terminal network may be substituted for a triac with corresponding terminal connections to provide triac control functions at greatly increased current levels through the load terminals however with triac level control signals applied to the third gating terminal. The network includes a triac and series connected diodes between the load terminals and a pair of inverse paralleled SCR''s in circuit therewith.
Inventors
- 👤 G Mcdonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:01
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/725
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
249 words
In combination in a power control circuit including a source of AC power and a load: bidirectional switching means normally exhibiting a high impedance characteristic between first and second current carrying terminals thereof and exhibiting a low impedance characteristic in response to the application of a control signal to a third gating terminal thereof and the application of opposite polarity voltages to the first and second current carrying terminals thereof, said first and second current carrying terminals connected in series circuit with said load and source of AC power; said bidirectional switching means including, a bidirectional thyristor having fourth and fifth current carrying terminals and a sixth gating terminal, said fourth and fifth current carrying terminals coupled respectively to said first and second current carrying terminals, and said sixth gating terminal coupled to said third gating terminal, a first unidirectional thyristor having seventh and eighth current carrying terminals and a ninth gating terminal said seventh and eighth current carrying terminals coupled respectively to said first and second current carrying terminals for conducting current in a predetermined direction between said first and second current carrying terminals and said ninth gating terminal coupled to said fifth current carrying terminal, a second unidirectional thyristor having tenth and eleventh current carrying terminals and a twelfth gating terminal, said tenth and eleventh current carrying terminals coupled respectively to said first and second current carrying terminals for conducting current in a direction opposite to said predetermined direction between said first and second current carrying terminals.
Claim 2
Dependent Claim
249 words
In combination in a power control circuit including a source of AC power and a load: bidirectional switching means normally exhibiting a high impedance characteristic between first and second current carrying terminals thereof and exhibiting a low impedance characteristic in response to the application of a control signal to a third gating terminal thereof and the application of opposite polarity voltages to the first and second current carrying terminals thereof, said first and second current carrying terminals connected in series circuit with said load and source of AC power; said bidirectional switching means including, a bidirectional thyristor having fourth and fifth current carrying terminals and a sixth gating terminal, said fourth and fifth current carrying terminals coupled respectively to said first and second current carrying terminals, and said sixth gating terminal coupled to said third gating terminal, a first unidirectional thyristor having seventh and eighth current carrying terminals and a ninth gating terminal said seventh and eighth current carrying terminals coupled respectively to said first and second current carrying terminals for conducting current in a predetermined direction between said first and second current carrying terminals and said ninth gating terminal coupled to said fifth current carrying terminal, a second unidirectional thyristor having tenth and eleventh current carrying terminals and a twelfth gating terminal, said tenth and eleventh current carrying terminals coupled respectively to said first and second current carrying terminals for conducting current in a direction opposite to said predetermined direction between said first and second current carrying terminals.
Claim 3
Dependent Claim
171 words
A control circuit for controlling AC current flow between first and second terminals in response to control signals applied to a third terminal comprising in combination: a first series circuit path comprising a triac and first and second diodes connected between said first and second terminals, the anodes of each of said first and second diodes individually connected respectively to said first and second terminals and the cathodes of said first and second diodes each individually connected respectively to the load terminals of said triac; a first SCR having an anode, cathode and gate electrode, said anode connected to said first terminal, said cathode connected to said second terminal and said gate electrode connected to the cathode of said second diode; a second SCR having an anode, cathode and gate electrode, said anode connected to said second terminal, said cathode connected to said first terminal, and said gate electrode connected to the cathode of said first diode; and means for coupling the gate electrode of said triac to said third terminal.
Claim 4
Dependent Claim
171 words
A control circuit for controlling AC current flow between first and second terminals in response to control signals applied to a third terminal comprising in combination: a first series circuit path comprising a triac and first and second diodes connected between said first and second terminals, the anodes of each of said first and second diodes individually connected respectively to said first and second terminals and the cathodes of said first and second diodes each individually connected respectively to the load terminals of said triac; a first SCR having an anode, cathode and gate electrode, said anode connected to said first terminal, said cathode connected to said second terminal and said gate electrode connected to the cathode of said second diode; a second SCR having an anode, cathode and gate electrode, said anode connected to said second terminal, said cathode connected to said first terminal, and said gate electrode connected to the cathode of said first diode; and means for coupling the gate electrode of said triac to said third terminal.
Claim 5
Dependent Claim
206 words
A power circuit comprising in combination: an AC current source; a load; a first diode having a cathode and an anode; a triac having first and second load terminals and a gate electrode; a second diode having a cathode and an anode; said cathode of said first diode connected to said first load terminal of said triac, said cathode of said second diode connected to said second load terminal of said triac, said anode of said first diode and said anode of said second diode connected in series circuit relationship with said AC current source and said load; a first silicon controlled rectifier having an anode, cathode, and gate electrode, said anode connected to the anode of said first diode, said cathode connected to the anode of said second diode, and said gate electrode connected to the cathode of said second diode; a second silicon controlled rectifier having an anode, cathode, and gate electrode, said anode connected to the anode of said second diode, said cathode connected to the anode of said first diode, and saId gate electrode connected to the cathode of said first diode; and, control circuit means coupled to the gate electrode of said triac for applying gating signals to said gate electrode.
Claim 6
Dependent Claim
206 words
A power circuit comprising in combination: an AC current source; a load; a first diode having a cathode and an anode; a triac having first and second load terminals and a gate electrode; a second diode having a cathode and an anode; said cathode of said first diode connected to said first load terminal of said triac, said cathode of said second diode connected to said second load terminal of said triac, said anode of said first diode and said anode of said second diode connected in series circuit relationship with said AC current source and said load; a first silicon controlled rectifier having an anode, cathode, and gate electrode, said anode connected to the anode of said first diode, said cathode connected to the anode of said second diode, and said gate electrode connected to the cathode of said second diode; a second silicon controlled rectifier having an anode, cathode, and gate electrode, said anode connected to the anode of said second diode, said cathode connected to the anode of said first diode, and saId gate electrode connected to the cathode of said first diode; and, control circuit means coupled to the gate electrode of said triac for applying gating signals to said gate electrode.
Claim 7
Dependent Claim
114 words
A triac controlled SCR circuit for controlling current flow between first and second terminals comprising in combination: a first unidirectional thyristor coupled between said first and second terminals for providing current flow in a first direction between said first and second terminals; a second unidirectional thyristor coupled between said first and second terminals for providing current flow in a second direction opposite to said first direction between said first and second terminals; a triac having first and second load terminals coupled to the gate electrodes of said first and second unidirectional thyristors respectively for providing gate drive for said unidirectional thyristors in response to gating signals applied to the gate electrode of said triac.
Claim 8
Dependent Claim
114 words
A triac controlled SCR circuit for controlling current flow between first and second terminals comprising in combination: a first unidirectional thyristor coupled between said first and second terminals for providing current flow in a first direction between said first and second terminals; a second unidirectional thyristor coupled between said first and second terminals for providing current flow in a second direction opposite to said first direction between said first and second terminals; a triac having first and second load terminals coupled to the gate electrodes of said first and second unidirectional thyristors respectively for providing gate drive for said unidirectional thyristors in response to gating signals applied to the gate electrode of said triac.
Claim 9
Dependent Claim
23 words
The invention according to claim 4 further comprising means for limiting the peak reverse voltage across gate and cathode of said unidirectional thyristors.
Claim 10
Dependent Claim
134 words
A triac controlled SCR circuit for controlling AC current flow between first and second terminals comprising in combination: a first unidirectional thyristor coupled between said first and second terminals for providing current flow in a first direction between said first and second terminals; a second unidirectional thyristor coupled between said first and second terminals for providing current flow in a second direction opposite to said first direction between said first and second terminals; a triac having first and second load terminals coupled to the gate electrodes of said first and second unidirectional thyristors respectively and providing said AC current flow during a predetermined time period in response to gating signals applied to the gate electrode of said triac, said first and second unidirectional thyristors providing said AC current flow after said predetermined time period.
Claim 11
Dependent Claim
134 words
A triac controlled SCR circuit for controlling AC current flow between first and second terminals comprising in combination: a first unidirectional thyristor coupled between said first and second terminals for providing current flow in a first direction between said first and second terminals; a second unidirectional thyristor coupled between said first and second terminals for providing current flow in a second direction opposite to said first direction between said first and second terminals; a triac having first and second load terminals coupled to the gate electrodes of said first and second unidirectional thyristors respectively and providing said AC current flow during a predetermined time period in response to gating signals applied to the gate electrode of said triac, said first and second unidirectional thyristors providing said AC current flow after said predetermined time period.
Claim 12
Dependent Claim
22 words
The invention according to claim 6 wherein said predetermined time period is substantially equal to the turn time of said unidirectional thyristors.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |