US3830619A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Burner control system
Assignee: Fireye Inc
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Filing: 1973-05-04
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Granted: 1974-08-20
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Expires: 1993-05-04
Abstract
Abstract A burner control system that locks out for flame failure but recycles to an ignition sequence after a power failure. Recycling can occur even if a flame is momentarily present in the combustion chamber when power is restored, but the system locks out if the flame is not extinguished within a predetermined period of time. Included in the control system is a control circuit with a lockout switch actuating circuit including a latchable switch means that closes when there is no flame and an energizing signal is applied, remains closed for the duration of the energizing signal, and opens when the signal has terminated. Closing of the latchable switch means is triggered by a control relay, and the control circuit is electrically isolated from greater voltages in the output of a flame sensor, thereby causing the latchable switch means to open at least as soon as the control relay is deenergized when an energizing signal is lost. A circuit to lockout for flame failure or a dangerously long flame persistence after power failure is also provided.
Inventors
- 👤 P Cade
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:03
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/20; F23N5/203; F23N5/02; F23N5/08; F23N5/082; F23N5/24; F23N5/242; F23N2227/00; F23N2227/22; F23N2227/28; F23N2229/00; F23N2231/00; F23N2231/04; F23N2231/06; F23N2231/12; F23N2231/20; F23N2233/00; F23N2233/06; F23N5/18
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
372 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, and control circuitry connected to a pair of input terminals, said control circuitry including a control relay energized in response to the application of an energizing signal at said input terminals while said flame sensor indicates lack of flame, a lockout switch actuating circuit including latchable switch means connected in an actuating path, means operable in response to the combination of an energizing signal applied at said input terminals and the absence of a flame indication from said flame sensor for closing said latchable switch means, a circuit for applying a latching signal to hold said latchable switch means closed for the duration of an applied energizing signal, said latchable switch means adapted to open in response to the loss of an energizing signal at said energizing terminals, a flame relay connected in series with said control relay, and normally closed contacts controlled by said flame relay connected in said actuating path in series with said latchable switch means, said flame relay connected to said energizing terminals for energization when said flame sensor indicates flame, the control relay-flame relay series circuit being characterized by an electrical impedance sufficient to maintain said control relay in an energized state when an energizing signal is present at said terminals but insufficient to enable energization of the control relay from an initial deenergized state, and rapid response means for removing a latching signal from said latchable switch means when an energizing signal is lost from said energizing terminals, and thereby causing said latchable switch means to open, said rapid response means operable at least as fast as the drop-out time of said control relay to open said latchable switch means at least as fast as said control relay is de-energized.
Claim 2
Dependent Claim
372 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, and control circuitry connected to a pair of input terminals, said control circuitry including a control relay energized in response to the application of an energizing signal at said input terminals while said flame sensor indicates lack of flame, a lockout switch actuating circuit including latchable switch means connected in an actuating path, means operable in response to the combination of an energizing signal applied at said input terminals and the absence of a flame indication from said flame sensor for closing said latchable switch means, a circuit for applying a latching signal to hold said latchable switch means closed for the duration of an applied energizing signal, said latchable switch means adapted to open in response to the loss of an energizing signal at said energizing terminals, a flame relay connected in series with said control relay, and normally closed contacts controlled by said flame relay connected in said actuating path in series with said latchable switch means, said flame relay connected to said energizing terminals for energization when said flame sensor indicates flame, the control relay-flame relay series circuit being characterized by an electrical impedance sufficient to maintain said control relay in an energized state when an energizing signal is present at said terminals but insufficient to enable energization of the control relay from an initial deenergized state, and rapid response means for removing a latching signal from said latchable switch means when an energizing signal is lost from said energizing terminals, and thereby causing said latchable switch means to open, said rapid response means operable at least as fast as the drop-out time of said control relay to open said latchable switch means at least as fast as said control relay is de-energized.
Claim 3
Dependent Claim
38 words
Burner control apparatus as claimed in claim 1, further including a second actuating path in said lockout switch actuating circuit, the second actuating path including normally closed controL relay contacts in series with normally open flame relay contacts.
Claim 4
Dependent Claim
35 words
Burner control apparatus as claimed in claim 1, wherein said means for closing the switch means comprises control relay contacts connected to trigger said latchable switch means to close when said control relay is energized.
Claim 5
Dependent Claim
243 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, an output circuit for said flame sensor connected to a pair of input terminals for the burner control apparatus, electrical storage means connected to smooth and maintain the signal at said output circuit during fluctuations in the signal at said input terminals, and means for applying an energizing signal at said input terminals in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, control circuitry connected to said input terminals, said control circuitry including a lockout switch actuating circuit, and latchable switch means in said actuating circuit connected in an actuating path, said latchable switch means when closed adapted to remain closed during the continuation of an energizing signal at said input terminals and to open upon the termination of such an energizing signal, and means to isolate said control circuitry from voltage levels across said flame sensor output circuit that are greater than the energizing signal applied at said input terminals, thereby enabling the signal at said input terminals to drop rapidly and said latchable switch means to rapidly open in response to a loss of energizing signal.
Claim 6
Dependent Claim
243 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, an output circuit for said flame sensor connected to a pair of input terminals for the burner control apparatus, electrical storage means connected to smooth and maintain the signal at said output circuit during fluctuations in the signal at said input terminals, and means for applying an energizing signal at said input terminals in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, control circuitry connected to said input terminals, said control circuitry including a lockout switch actuating circuit, and latchable switch means in said actuating circuit connected in an actuating path, said latchable switch means when closed adapted to remain closed during the continuation of an energizing signal at said input terminals and to open upon the termination of such an energizing signal, and means to isolate said control circuitry from voltage levels across said flame sensor output circuit that are greater than the energizing signal applied at said input terminals, thereby enabling the signal at said input terminals to drop rapidly and said latchable switch means to rapidly open in response to a loss of energizing signal.
Claim 7
Dependent Claim
116 words
Burner control apparatus as claimed in claim 4, further including a second electrical storage means of lesser capacity than said flame sensor output circuit storage means, connected to smooth the signal at said latchable switch means, and a control relay energized in response to the application of an energizing signal at said input terminals while said flame sensor indicates lack of flame, said second electrical storage means adapted to rapidly reduce the energizing signal at said latchable switch means when an energizing signal is lost at said input terminals, thereby enabling said latchable switch means to open upon loss of an energizing signal at said input terminals at least as soon as said control relay deenergizes.
Claim 8
Dependent Claim
184 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, and control circuitry connected to a pair of input terminals, said control circuitry including a lockout switch actuating circuit, latchable switch means in said actuating circuit connected in an actuating path, said latchable switch means when closed adapted to remain closed during the continuation of an energizing signal at said energizing terminals, trigger means for closing said latchable switch means, and a circuit for energizing said trigger means a predetermined period of time after the occurrence of the combination of a request for burner operation from said operating control together with a no-flame indication from said flame sensor.
Claim 9
Dependent Claim
184 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, and control circuitry connected to a pair of input terminals, said control circuitry including a lockout switch actuating circuit, latchable switch means in said actuating circuit connected in an actuating path, said latchable switch means when closed adapted to remain closed during the continuation of an energizing signal at said energizing terminals, trigger means for closing said latchable switch means, and a circuit for energizing said trigger means a predetermined period of time after the occurrence of the combination of a request for burner operation from said operating control together with a no-flame indication from said flame sensor.
Claim 10
Dependent Claim
43 words
Burner control apparatus as claimed in claim 6, wherein said trigger means comprises a control relay in combination with a set of control relay contacts, said contacts connected to said latchable switch mEans to trigger closing thereof when said control relay is energized.
Claim 11
Dependent Claim
231 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, control circuitry connected to a pair of input terminals, including an actuating circuit for said lockout switch, said actuating circuit including first and second switches connected in series to form a first actuating path, and third and fourth switches connected in series to form a second actuating path, said first switch respectively opened and closed in response to flame and no-flame indications from the flame sensor, said second switch closed in response to an energizing signal applied at said input terminals, held closed for the duration of an energizing signal, and opened in response to loss of an energizing signal at the input terminals, said third switch respectively closed and opened in response to flame and no-flame indications from said flame sensor, and said fourth switch respectively closed and opened in response to the absence or presence of an energizing signal at said input terminals.
Claim 12
Dependent Claim
231 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, control circuitry connected to a pair of input terminals, including an actuating circuit for said lockout switch, said actuating circuit including first and second switches connected in series to form a first actuating path, and third and fourth switches connected in series to form a second actuating path, said first switch respectively opened and closed in response to flame and no-flame indications from the flame sensor, said second switch closed in response to an energizing signal applied at said input terminals, held closed for the duration of an energizing signal, and opened in response to loss of an energizing signal at the input terminals, said third switch respectively closed and opened in response to flame and no-flame indications from said flame sensor, and said fourth switch respectively closed and opened in response to the absence or presence of an energizing signal at said input terminals.
Claim 13
Dependent Claim
58 words
Burner control apparatus as claimed in claim 8, including a trigger circuit to apply a closing signal from said input terminals to said second switch, wherein said fourth switch is connected to said trigger circuit to bypass said second switch and prevent the application of a closing signal thereto during the time that said fourth switch is closed.
Claim 14
Dependent Claim
84 words
Burner control apparatus as claimed in claim 8 and further including a first relay for operating said fuel control, circuitry for energizing said first relay in response to an energizing signal applied at said input terminals, a second relay responsive to a signal from said flame sensor indicating the presence of flame in the combustion chamber, and circuitry for opening said second switch prior to release of said first and second relays in response to loss of an energizing signal at said input terminals.
Claim 15
Dependent Claim
53 words
Burner control apparatus as claimed in claim 10 wherein said release allowing circuitry includes an asymmetrically conductive device connected in series between said input terminals and said first and second relays and a capacitor for delaying release of said first and second relays upon loss of an energizing signal at said input terminals.
Claim 16
Dependent Claim
108 words
Burner control apparatus as claimed in claim 11 and further including time delay circuit responsive to an energizing signal applied at said input terminals for delaying energization of said first relay; and a fifth switch respectively closed and opened in response to flame and no flame indications from said flame sensor, said fifth switch being connected to said time delay circuitry to prevent completion of a time delay interval to energize said first relay during the presence of a flame indication from said flame sensor; and wherein said second switch is a controlled rectifier and said fourth switch is opened in response to energization of said first relay.
Claim 17
Dependent Claim
213 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, control circuitry cOnnected to a pair of input terminals, a lockout switch actuating circuit in said control circuitry, said actuating circuit including a silicon controlled rectifier, and a switch respectively opened and closed in response to flame and no-flame indications from said flame sensor, the anode-cathode circuit of said silicon controlled rectifier connected in series with said switch to form a lockout switch actuating path, a trigger circuit connected to the gate of the silicon controlled rectifier, said trigger circuit including a trigger switch controlling the application of a gating signal from said input terminals to said gate, and means for operating said trigger switch in response to a request for burner operation from said operating control to apply a gating signal to said silicon controlled rectifier.
Claim 18
Dependent Claim
213 words
Burner control apparatus for use with a fuel burner installation having a combustion chamber, an operating control, a fuel control for controlling the flow of fuel to the combustion chamber, an ignition control for igniting fuel in the combustion chamber, a flame sensor for sensing the presence of flame in the combustion chamber, and means for applying an energizing signal to the burner control apparatus in response to a request for burner operation from said operating control, comprising: a lockout switch to shut down burner operation, control circuitry cOnnected to a pair of input terminals, a lockout switch actuating circuit in said control circuitry, said actuating circuit including a silicon controlled rectifier, and a switch respectively opened and closed in response to flame and no-flame indications from said flame sensor, the anode-cathode circuit of said silicon controlled rectifier connected in series with said switch to form a lockout switch actuating path, a trigger circuit connected to the gate of the silicon controlled rectifier, said trigger circuit including a trigger switch controlling the application of a gating signal from said input terminals to said gate, and means for operating said trigger switch in response to a request for burner operation from said operating control to apply a gating signal to said silicon controlled rectifier.
Claim 19
Dependent Claim
46 words
Burner control apparatus as claimed in claim 13, further including a switch respectively closed and opened in response to flame and no-flame indications from said flame sensor, said switch connected in series with said trigger switch to form a second actuating path for the lockout switch.
References Cited (Backward Citations)
US3472220A
Cited
US3705783A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |