US3648075A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zero voltage switching ac relay circuit
Assignee: Teledyne Inc
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Filing: 1970-06-01
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Granted: 1972-03-07
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Expires: 1990-06-01
Abstract
Abstract An AC relay circuit is disclosed which includes a triac as its active switch element. A full wave rectifier is connected between one of the primary terminals and the gate terminal of the triac. A control switch is provided between the load terminals of the rectifier. First control means are provided which are responsive to an input control signal for closing the control switch, thereby triggering the triac into conduction. Second control means are provided for rendering the control switch nonresponsive to the first control means whenever the magnitude of the AC voltage to be controlled exceeds a predetermined value.
Inventors
- 👤 Roy J Mankovitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:11
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/13; H03K17/136
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
131 words
An alternating current relay circuit comprising, in combination: a. a triac having first and second primary terminals and a gate terminal; b. means for applying an AC voltage to be controlled to said primary terminals; c. a full wave rectifier having input terminals and positive and negative load terminals, said input terminals being connected between one of said primary terminals and said gate terminal of said triac; d. a control switch connected between said load terminals of said full wave rectifier; e. first control means responsive to a control signal for closing said control switch, thereby triggering said triac into condition; and f. second control means for rendering said control switch nonresponsive to said first control means whenever the magnitude of said AC voltage to be controlled exceeds a predetermined value.
Claim 2
Dependent Claim
131 words
An alternating current relay circuit comprising, in combination: a. a triac having first and second primary terminals and a gate terminal; b. means for applying an AC voltage to be controlled to said primary terminals; c. a full wave rectifier having input terminals and positive and negative load terminals, said input terminals being connected between one of said primary terminals and said gate terminal of said triac; d. a control switch connected between said load terminals of said full wave rectifier; e. first control means responsive to a control signal for closing said control switch, thereby triggering said triac into condition; and f. second control means for rendering said control switch nonresponsive to said first control means whenever the magnitude of said AC voltage to be controlled exceeds a predetermined value.
Claim 3
Dependent Claim
98 words
The relay circuit of claim 1 in which said control switch comprises a controlled rectifier having an anode, a cathode and a gate terminal, said anode being connected to said positive load terminal of said full wave rectifier and said cathode being connected to said negative load terminal of said full wave rectifier and in which said first control means comprises means for applying a control signal to said relay circuit and means responsive to the application of said control signal to said relay circuit for applying a gating signal to said gate terminal of said controlled rectifier.
Claim 4
Dependent Claim
52 words
The relay circuit of claim 2 in which said second control means comprises a saturable transistor connected between said gate terminal and said cathode of said controlled rectifier and third control means for driving said transistor into saturation whenever the magnitude of said AC voltage to be controlled exceeds said predetermined value.
Claim 5
Dependent Claim
26 words
The relay circuit of claim 3 in which said third control means comprises a voltage divider connected between said load terminals of said full wave rectifier.
Claim 6
Dependent Claim
27 words
The relay circuit of claim 4 which further includes a current limiting resistor connected in series with one of said input terminals of said full wave rectifier.
Claim 7
Dependent Claim
69 words
The relay circuit of claim 4 in which said first control means further includes means responsive to the application of said control signal to said relay circuit for generating an AC gating signal having a frequency at least 10 times higher than the frequency of said AC voltage to be controlled and means for applying said AC gating signal between gate terminal and said cathode of said controlled rectifier.
Claim 8
Dependent Claim
48 words
The relay circuit of claim 6 in which said first control means further includes constant current means responsive to the application of said control signal to said relay circuit for developing a constant current signal and means for inverting said constant current signal into said AC gating signal.
Claim 9
Dependent Claim
117 words
The relay circuit of claim 7 in which said constant current means comprises a series circuit of a resistor and a diode, means for applying said control signal to said series circuit, whereby a constant forward voltage drop is developed across said diode whenever said control signal is applied, regardless of the value of said control signal, a transistor having a collector electrode, a base electrode and a emitter electrode, means connecting said base electrode and said emitter electrode across said diode, thereby causing a constant base current in said transistor whenever said control signal is applied, thereby causing the collector current in said transistor to be of a constant value whenever said control signal is applied.
Claim 10
Dependent Claim
55 words
The relay circuit of claim 8 which further includes a rectifier connected between said means for applying a control signal to said relay circuit and said series circuit of said resistor and Said diode, whereby said constant forward voltage drop is developed across said diode regardless of whether said control signal is DC or AC.
Claim 11
Dependent Claim
30 words
The relay circuit of claim 9 which further includes a current-limiting resistor connected in series between said full wave rectifier and said one of said primary terminals of said triac.
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) | 1975-03-07 | 1975-09-06 | 1976-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-07 | 1979-09-06 | 1980-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-07 | 1983-09-06 | 1984-03-07 | $7700.00 | Window Closed / Lapsed |