US3683372A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multimode self-checking flame detector
Assignee: Forney International Inc
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Filing: 1971-05-27
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Granted: 1972-08-08
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Expires: 1991-05-27
Abstract
Abstract An alarm signal is operated by a multimode self-checking circuit upon failure of such circuit, or failure of a flame being monitored by a device that is sensitive to such flame. This circuit is provided with a plurality of different drive circuits each of which is designated for a flame sensitive device, such that the flame can be monitored.
Inventors
- 👤 Robert Horn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:23
CPC Classifications
G; G08; G08B; G08B17/00; G08B17/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
153 words
A multimode flame detector system capable of use with any selected one of a plurality of different types of ultraviolet and photosensitive tubes that are sensitive to rays emitted by a flame to be monitored thereby comprising means for indicating when such flame is in an ''''out'''' condition, a control circuit containing an amplifier circuit for operating the ''''out'''' condition indicating means, a plurality of individual drive circuits corresponding to such tube types, each being capable of delivering flame condition signals suitable for reception by said amplifier circuit when energized and connected thereto; means for connecting the selected type of tube exclusively to the drive circuit corresponding thereto, and means for delivering only the output of the so connected drive circuit to the input of said amplifier of the control circuit; whereby the system functions equally well with any selected type of ultraviolet and photosensitive tube that is suitable for monitoring such flame.
Claim 2
Dependent Claim
153 words
A multimode flame detector system capable of use with any selected one of a plurality of different types of ultraviolet and photosensitive tubes that are sensitive to rays emitted by a flame to be monitored thereby comprising means for indicating when such flame is in an ''''out'''' condition, a control circuit containing an amplifier circuit for operating the ''''out'''' condition indicating means, a plurality of individual drive circuits corresponding to such tube types, each being capable of delivering flame condition signals suitable for reception by said amplifier circuit when energized and connected thereto; means for connecting the selected type of tube exclusively to the drive circuit corresponding thereto, and means for delivering only the output of the so connected drive circuit to the input of said amplifier of the control circuit; whereby the system functions equally well with any selected type of ultraviolet and photosensitive tube that is suitable for monitoring such flame.
Claim 3
Dependent Claim
24 words
A multimode flame detector system as defined by claim 1, in which a unitary circuit module contains said drive circuits and tube connection means.
Claim 4
Dependent Claim
82 words
A multimode flame detector system as defined by claim 2, in which said module consists of a circuit board containing two different UV tube drive circuits and a phototube drive circuit, a wave shaping circuit for said UV tube drive circuits, means for connecting a selected one of said UV tube drive circuits to said wave shaping circuit, and means for connecting the outpuT of either said wave shaping circuit, or said phototube drive circuit, to the input of said amplifier circuit.
Claim 5
Dependent Claim
74 words
A multimode flame detector system as defined by claim 3, in which said control circuit includes self checking circuit means comprising means acting to periodically blind the tube to such flame when periodically energized to check the output of the circuit for the so simulated flame loss, means acting to remove such blind when the circuit is functioning normally, and means acting to operate said means to indicate a circuit malfunction when that occurs.
Claim 6
Dependent Claim
44 words
A system as defined by claim 4, including means for adjusting the sensitivity of the amplifier circuit to the response of the tube and, hence, the flame condition, and means for adjusting the amplifier for varying background flame conditions independently of such sensitivity adjustment.
Claim 7
Dependent Claim
30 words
A system as defined by claim 5, including means for preselecting such sensitivity adjustment for at least two settings, and external means for selecting a desired one of said settings.
Claim 8
Dependent Claim
14 words
A system as defined by claim 5, including means for externally programming such background.
Claim 9
Dependent Claim
17 words
A system as defined by claim 5, including independent ''''Flame On'''' and ''''Flame Out'''' time delay circuits.
Claim 10
Dependent Claim
20 words
A system as defined by claim 5, in which solid state components including outputs are used substantially throughout the system.
Claim 11
Dependent Claim
19 words
A system as defined by claim 5 in which said checking circuit is a component of the amplifier-control circuit.
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) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |