Patent US4039844A successfully refreshed from Google Patents.
US4039844A
Expired / Lapsed
US
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Flame monitoring system
Assignee: Fireye Inc
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Filing: 1975-03-20
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Granted: 1977-08-02
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Expires: 1995-03-20
Abstract
Abstract A flame monitoring system includes a flame sensor for producing a flame signal as a function of flame conditions in a monitored environment and flame signal enhancing circuitry coupled to the flame sensor. The flame signal enhancing circuitry has a first response as a function of a first characteristic of the flame signal and a second response different from the first response as a function of a second characteristic of the flame signal and is arranged to combine the first and second responses to provide an enhanced flame signal representative of the monitored flame.
Inventors
- 👤 Malcolm F. MacDonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:56
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/08; F23N5/082; F23N2229/00; F23N2229/16; F23N2229/22; F23N2237/00; F23N2237/02; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
120 words
A flame monitoring system comprising a flame sensor producing an electrical output signal having both higher frequency and lower frequency components derived from a monitored flame environment, and signal processing circuitry connected to said flame sensor and responsive to both said higher frequency and said lower frequency components of said output signal, said signal processing circuitry including an amplifier and a feedback network with a variable impedance and being arranged so that said higher frequency components are amplified and the amplifier gain is decreased in response to an increase in said lower frequency components such that the resulting output of said signal processing circuitry provides discrimination between the flame monitored by said sensor and other conditions in the supervised environment.
Claim 2
Dependent Claim
120 words
A flame monitoring system comprising a flame sensor producing an electrical output signal having both higher frequency and lower frequency components derived from a monitored flame environment, and signal processing circuitry connected to said flame sensor and responsive to both said higher frequency and said lower frequency components of said output signal, said signal processing circuitry including an amplifier and a feedback network with a variable impedance and being arranged so that said higher frequency components are amplified and the amplifier gain is decreased in response to an increase in said lower frequency components such that the resulting output of said signal processing circuitry provides discrimination between the flame monitored by said sensor and other conditions in the supervised environment.
Claim 3
Dependent Claim
21 words
The system as claimed in claim 1 wherein said flame sensor is a photosensor that has a high speed response characteristic.
Claim 4
Dependent Claim
65 words
The system as claimed in claim 1 wherein said signal processing circuit has a transfer function of the form ##EQU2## where E O (AC) is the output signal of said signal processing circuitry, I D (AC) is a higher frequency component of said flame signal, I D (DC) is a lower frequency component of said flame signal, and n is in the range of 0.6-0.8.
Claim 5
Dependent Claim
59 words
The system as claimed in claim 2 wherein said signal processing circuitry further includes a radiation source connected to the output of said amplifier, and said feedback network includes a radiation responsive impedance element that is optically coupled to said radiation source and that has a response speed that is much slower than the response speed of said photosensor.
Claim 6
Dependent Claim
28 words
The system as claimed in claim 4 and further including selective attenuation circuitry coupled to said signal processing circuitry for attenuating components of said signal processing circuitry output.
Claim 7
Dependent Claim
32 words
The system as claimed in claim 5 wherein said selective attenuation circuitry includes band pass amplifier circuitry that has a pass band corresponding to the frequency range of said higher frequency components.
Claim 8
Dependent Claim
96 words
A flame monitoring system comprising: a flame sensor for producing a flame signal as a function of flame conditions in a monitored environment, flame signal enhancing circuitry coupled to said flame sensor, said flame signal enhancing circuitry having an amplifier and a feedback network with a variable impedance and being arranged so that a first characteristic of said flame signal is amplified and the amplifier gain is decreased in response to an increase in a second characteristic of said flame signal to provide an enhanced flame signal representative of the monitored flame as an output signal.
Claim 9
Dependent Claim
96 words
A flame monitoring system comprising: a flame sensor for producing a flame signal as a function of flame conditions in a monitored environment, flame signal enhancing circuitry coupled to said flame sensor, said flame signal enhancing circuitry having an amplifier and a feedback network with a variable impedance and being arranged so that a first characteristic of said flame signal is amplified and the amplifier gain is decreased in response to an increase in a second characteristic of said flame signal to provide an enhanced flame signal representative of the monitored flame as an output signal.
Claim 10
Dependent Claim
33 words
The system as claimed in claim 7 wherein said first characteristic is a higher frequency component of said flame signal and said second characteristic is a lower frequency component of said flame signal.
Claim 11
Dependent Claim
60 words
The system as claimed in claim 8 wherein said flame signal enhancing circuitry has a transfer function of the form ##EQU3## where E O (AC) is said enhanced flame signal, I D (AC) is said first characteristic of said flame signal, I D (DC) is said second characteristic of said flame signal, and n is in the range of 0.6-0.8.
Claim 12
Dependent Claim
40 words
The system as claimed in claim 7 and further including selective attenuation circuitry coupled to said flame signal enhancing circuitry for attenuating components of said output signal corresponding to the frequency range of said second characteristic of said flame signal.
Claim 13
Dependent Claim
28 words
The system as claimed in claim 10 wherein said selective attenuation circuitry has a low frequency cutoff that excludes all signals in the range of said second characteristic.
Claim 14
Dependent Claim
16 words
The system as claimed in claim 11 wherein said low frequency cutoff is about 200 Hertz.
Claim 15
Dependent Claim
34 words
The system as claimed in claim 12 wherein said selective attenuation circuitry includes a band pass amplifier that has a center frequency of about 400 Hertz and a pass band of about 400 Hertz.
Claim 16
Dependent Claim
22 words
The system as claimed in claim 12 and further including gain adjustment means for varying the magnitude of said enhanced flame signal.
Claim 17
Dependent Claim
14 words
The system as claimed in claim 7 wherein said flame sensor is a photosensor.
Claim 18
Dependent Claim
21 words
The system as claimed in claim 15 wherein said photosensor is a solid state device that has a photosensitive junction region.
Claim 19
Dependent Claim
17 words
The system as claimed in claim 16 wherein said solid state device is a silicon photodiode device.
Claim 20
Dependent Claim
60 words
The system as claimed in claim 7 wherein said flame signal enhancing circuitry has a transfer function of the form ##EQU4## where E O (AC) is said enhanced flame signal, I D (AC) is said first characterstic of said flame signal, I D (DC) is said second characteristic of said flame signal, and n is in the range of 0.6-0.8.
Claim 21
Dependent Claim
24 words
The system as claimed in claim 18 wherein said feedback network includes an impedance element that has a damped response to said flame signal.
Claim 22
Dependent Claim
40 words
The system as claimed in claim 19 and further including a radiation source coupled to be energized by the output of said amplifier and a slow speed photoresistor connected in said feedback network and optically coupled to said radiation source.
Claim 23
Dependent Claim
22 words
The system as claimed in claim 20 and further including gain adjustment means for varying the magnitude of said enhanced flame signal.
Claim 24
Dependent Claim
41 words
The system as claimed in claim 21 and further including selective attenuation circuitry coupled to said flame signal enhancing circuitry for attenuating components of said enhanced flame signal corresponding to the frequency range of said second characteristic of said flame signal.
Claim 25
Dependent Claim
22 words
The system as claimed in claim 22 wherein said sensor is a solid state silicon device that has a photosensitive junction region.
Claim 26
Dependent Claim
47 words
The system as claimed in claim 23 wherein said first characteristic is a higher frequency component of said flame signal and said second characteristic is a lower frequency component of said flame signal and said selective attenuation circuitry has a low frequency cutoff of about 200 Hertz.
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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) | 1980-08-01 | 1981-01-31 | 1981-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-01 | 1985-01-31 | 1985-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-01 | 1989-01-31 | 1989-08-02 | $7700.00 | Window Closed / Lapsed |