US4140474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Burner control system
Assignee: Kidde Inc
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Filing: 1977-07-13
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Granted: 1979-02-20
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Expires: 1997-07-13
Abstract
Abstract A burner control system including a valve for controlling the flow of fuel to a burner, a flame sensor for producing a flame signal in response to the presence of flame at the burner, a start-up circuit for producing a start-up signal, a control circuit for opening the valve to establish fuel flow in response to either the flame or start-up signal, and a timing capacitor first delays the generation of the start-up signal while charging during a predetermined purge period after energization of the start-up circuit and then terminates the start-up signal while discharging during a predetermined ignition period. A monostable electronic switch produces the start-up signal in response to the charge level on the timing capacitor and a valve initiator for opening the valve is powered by energy discharged by the timing capacitor during the ignition period.
Inventors
- 👤 William J. Bowles
- 👤 William J. Riordan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:43
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/20; F23N5/203; F23N2223/00; F23N2223/22; F23N2223/26; F23N2227/00; F23N2227/04; F23N2227/36
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
163 words
Burner control circuit apparatus comprising: valve means for controlling the flow of fuel to a burner; flame sensor means for producing a flame signal in response to the presence of flame at the burner; start-up circuit means for producing a start-up signal; control circuit means for opening said valve means to establish fuel flow to the burner in response to either said flame signal or said start-up signal; supply means for energizing said start-up circuit means and said control circuit means; and timing means for first delaying the generation of said start-up signal for a predetermined purge period after energization of said start-up circuit means and then terminating said start-up signal after a predetermined ignition period; said timing means comprising a timing capacitor with a predetermined charge time for establishing one of said periods and a predetermined discharge time for establishing the other of said periods, a charging circuit for charging said timing capacitor, and a discharge circuit for discharging said timing capacitor.
Claim 2
Dependent Claim
163 words
Burner control circuit apparatus comprising: valve means for controlling the flow of fuel to a burner; flame sensor means for producing a flame signal in response to the presence of flame at the burner; start-up circuit means for producing a start-up signal; control circuit means for opening said valve means to establish fuel flow to the burner in response to either said flame signal or said start-up signal; supply means for energizing said start-up circuit means and said control circuit means; and timing means for first delaying the generation of said start-up signal for a predetermined purge period after energization of said start-up circuit means and then terminating said start-up signal after a predetermined ignition period; said timing means comprising a timing capacitor with a predetermined charge time for establishing one of said periods and a predetermined discharge time for establishing the other of said periods, a charging circuit for charging said timing capacitor, and a discharge circuit for discharging said timing capacitor.
Claim 3
Dependent Claim
30 words
An apparatus according to claim 1 wherein said timing capacitor is charged by said charging circuit during said purge period and discharged by said discharge circuit during said ignition period.
Claim 4
Dependent Claim
31 words
An apparatus according to claim 2 wherein said start-up circuit means comprises a monostable electronic switching means for producing said start-up signal in response to the charge level on said capacitor.
Claim 5
Dependent Claim
36 words
An apparatus according to claim 3 wherein said control circuit means comprises valve initiator means for producing a valve signal effective to open said valve means, said valve initiator means being powered by said flame signal.
Claim 6
Dependent Claim
23 words
An apparatus according to claim 4 wherein said valve initiator circuit is powered by energy discharged from said capacitor during said ignition period.
Claim 7
Dependent Claim
34 words
An apparatus according to claim 1 including ignition means for igniting fuel supplied by said valve means to the burner and means for activating said ignition means at the outset of said ignition period.
Claim 8
Dependent Claim
30 words
An apparatus according to claim 6 wherein said timing capacitor is charged by said charging circuit during said purge period and discharged by said discharge circuit during said ignition period.
Claim 9
Dependent Claim
31 words
An apparatus according to claim 7 wherein said start-up circuit means comprises a monostable electronic switching means for producing said start-up signal in response to the charge level on said capacitor.
Claim 10
Dependent Claim
36 words
An apparatus according to claim 8 wherein said control circuit means comprises valve initiator means for producing a valve signal effective to open said valve means, said valve initiator means being powered by said flame signal.
Claim 11
Dependent Claim
23 words
An apparatus according to claim 9 wherein said valve initiator circuit is powered by energy discharged from said capacitor during said ignition period.
Claim 12
Dependent Claim
171 words
Burner control circuit apparatus comprising: valve means for controlling the flow of fuel to a burner; flame sensor means for producing a flame signal in response to the presence of flame at the burner; timing means for producing a predetermined purge period followed by a predetermined ignition period; start-up circuit means for initiating a start-up signal at the end of said purge period and terminating said start-up signal at the end of said ignition period, said start-up circuit means comprising a monostable multivibrator (multiple state electronic switch means) stable in one state and with positive feedback to establish rapid switching into said one state, said (electronic switch means) monostable multivibrator producing said start-up signal in a state other than said one state and terminating said start-up signal in said one state; control circuit means for opening said valve means to establish fuel flow to the burner in response to either said flame signal or said start-up signal; and supply means for energizing said start-up circuit means and said control circuit means.
Claim 13
Dependent Claim
171 words
Burner control circuit apparatus comprising: valve means for controlling the flow of fuel to a burner; flame sensor means for producing a flame signal in response to the presence of flame at the burner; timing means for producing a predetermined purge period followed by a predetermined ignition period; start-up circuit means for initiating a start-up signal at the end of said purge period and terminating said start-up signal at the end of said ignition period, said start-up circuit means comprising a monostable multivibrator (multiple state electronic switch means) stable in one state and with positive feedback to establish rapid switching into said one state, said (electronic switch means) monostable multivibrator producing said start-up signal in a state other than said one state and terminating said start-up signal in said one state; control circuit means for opening said valve means to establish fuel flow to the burner in response to either said flame signal or said start-up signal; and supply means for energizing said start-up circuit means and said control circuit means.
Claim 14
Dependent Claim
45 words
An apparatus according to claim 11 wherein said multivibrator comprises a pair of three-terminal semiconductors, one conductive in said one state and the other conductive in said other state, and energy storage means connected to said one semiconductor and effective to maintain current flow therein.
Claim 15
Dependent Claim
27 words
An apparatus according to claim 2 wherein said one semiconductor is a transistor and said energy storage means is a capacitor connected to the base lead thereof.
Claim 16
Dependent Claim
22 words
An apparatus according to claim 13 wherein said other semiconductor is a transistor and including a diode connected to the base thereof.
Claim 17
Dependent Claim
34 words
An apparatus according to claim 11 including ignition means for igniting fuel supplied by said valve means to the burner and means for activating said ignition means at the outset of said ignition period.
Claim 18
Dependent Claim
15 words
An apparatus according to claim 15 wherein said electronic switch means comprises a monostable multivibrator.
Claim 19
Dependent Claim
45 words
An apparatus according to claim 16 wherein said multivibrator comprises a pair of three-terminal semiconductors, one conductive in said one state and the other conductive in said other state, and energy storage means connected to said one semiconductor and effective to maintain current flow therein.
Claim 20
Dependent Claim
27 words
An apparatus according to claim 17 wherein said one semiconductor is a transistor and said energy storage means is a capacitor connected to the base electrode thereof.
Claim 21
Dependent Claim
22 words
An apparatus according to claim 18 wherein said other semiconductor is a transistor and including a diode connected to the base thereof.
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) | 1982-02-19 | 1982-08-21 | 1983-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-19 | 1986-08-21 | 1987-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-19 | 1990-08-21 | 1991-02-20 | $7700.00 | Window Closed / Lapsed |