US3805259A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Smoke and fire alarm system
Assignee: Japan Kinoko Research Center Foundation
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Filing: 1971-10-18
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Granted: 1974-04-16
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Expires: 1991-10-18
Abstract
Abstract A system for of detecting smoke or fire at a protected site, comprising a spark gap connected against the source of breakdown potential and exposed to the ambient air at the site. The improvement is based upon the discovery that particles present in smoke or the products of combustion induce a premature breakdown of the normally dielectric gas in the gap to initiate a signal which can be used to control a device or to alarm personnel in the region of the protected site.
Inventors
- 👤 K Inoue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:03
CPC Classifications
G; G08; G08B; G08B17/00; G08B17/10; G08B17/117
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
108 words
A system for warning of a smoke or fire condition comprising: electrode means forming a discharge gap bridged by ambient air; a source of electric pulses with an output frequency of 0.01 to 10 Hz connected across said gap and including an electrolet pile in circuit with said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap across thE electrode means and responsive to the breakdown thereof for producing a warning signal.
Claim 2
Independent Claim
108 words
A system for warning of a smoke or fire condition comprising: electrode means forming a discharge gap bridged by ambient air; a source of electric pulses with an output frequency of 0.01 to 10 Hz connected across said gap and including an electrolet pile in circuit with said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap across thE electrode means and responsive to the breakdown thereof for producing a warning signal.
Claim 3
Dependent Claim
20 words
The system defined in claim 1 wherein said source produces pulses of a pulse width of 1 to 100 microseconds.
Claim 4
Dependent Claim
50 words
The system defined in claim 1 wherein said source includes a dry-cell or battery, an oscillator operated thereby and a stepup transformer having a primary winding operatively connected with the output of said oscillator and a secondary winding connected in circuit with said gap for applying thereto said voltage pulses.
Claim 5
Dependent Claim
17 words
The system defined in claim 1 wherein said gap has a width of 0.1 to 1 mm.
Claim 6
Dependent Claim
38 words
The system defined in claim 1 wherein said detector means includes a resistor in circuit with said gap and a transistor network bridged across said resistor for changing its state in response to the passage of current therethrough.
Claim 7
Dependent Claim
26 words
The system defined in claim 1 further comprising a printed circuit board, said detector means, said source and said electrode means being mounted on said board.
Claim 8
Independent Claim
117 words
A system forwarning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air; a source of electric pulses with an output frequency of 0.01 to 10 Hz connected across said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap across the electrode means and responsive to the breakdown thereof for producing a warning signal, said electrode means including a bimetal element deflectable by temperature rise to bridge said gap and operate said detector means.
Claim 9
Independent Claim
117 words
A system forwarning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air; a source of electric pulses with an output frequency of 0.01 to 10 Hz connected across said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap across the electrode means and responsive to the breakdown thereof for producing a warning signal, said electrode means including a bimetal element deflectable by temperature rise to bridge said gap and operate said detector means.
Claim 10
Independent Claim
85 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air; an electrolet pile connected in circuit with said gap for applying thereto a potential of a magnitude insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap and responsive to the breakdown thereof for producing a warning signal.
Claim 11
Independent Claim
85 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air; an electrolet pile connected in circuit with said gap for applying thereto a potential of a magnitude insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap and responsive to the breakdown thereof for producing a warning signal.
Claim 12
Dependent Claim
18 words
The system defined in claim 8 further comprising energization means connectable across said electrolet pile for polarizing same.
Claim 13
Dependent Claim
27 words
The system defined in claim 8 further comprising a printed circuit board, said electrolet pile, said detector means and said electrode means being mounted on said board.
Claim 14
Dependent Claim
64 words
The system defined in claim 8 wherein said detector means includes an oscillator energizable upon breakdown of said gap, transducer means energizable by said oscillator, locking means for keeping said oscillator to oscillate once gap breakdown is detected to continue said transducer to be energized independently of gap potential, and switch means associated with said locking means for terminating the operation of said oscillator.
Claim 15
Independent Claim
96 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air; a source of electric pulses connected across said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles, said source including an electrolet pile in circuit with said gap; and detector means connected to said gap and responsive to the breakdown thereof for producing a warning signal.
Claim 16
Independent Claim
96 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air; a source of electric pulses connected across said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles, said source including an electrolet pile in circuit with said gap; and detector means connected to said gap and responsive to the breakdown thereof for producing a warning signal.
Claim 17
Dependent Claim
30 words
The system defined in claim 12 wherein said source has an output frequency of 0.01 to 10 Hz and produces pulses of a pulse width of 1 to 100 microseconds.
Claim 18
Dependent Claim
49 words
The system defined in claim 13 wherein said source includes a dry-cell or battery, an oscillator operated thereby and a transformer having a primary wiNding operatively connected with the output of said oscillator and a secondary winding connected in circuit with said gap for applying thereto said voltage pulses.
Claim 19
Dependent Claim
17 words
The system defined in claim 12 wherein said gap has a width of 0.1 to 1 mm.
Claim 20
Dependent Claim
27 words
The system defined in claim 12 wherein said electrode means includes a bimetal element deflectable by temperature rise to bridge said gap and operate said detector means.
Claim 21
Dependent Claim
38 words
The system defined in claim 12 wherein said detector means includes a resistor in circuit with said gap and a transistor network bridged across said resistor for changing its state in response to the passage of current therethrough.
Claim 22
Dependent Claim
26 words
The system defined in claim 12 wherein said detector means includes an oscillator energized upon breakdown of said gap and transducer means energizable by said oscillator.
Claim 23
Dependent Claim
26 words
The system defined in claim 12, furhter comprising a printed circuit board, said detector means, said source and said electrode means being mounted on said board.
Claim 24
Independent Claim
100 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air and including a pointed electrode poled as cathodic and a planar electrode poled as anodic; a source of electric pulses connected across said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap and responsive to the breakdown thereof for producing a warning signal.
Claim 25
Independent Claim
100 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a discharge gap bridged by ambient air and including a pointed electrode poled as cathodic and a planar electrode poled as anodic; a source of electric pulses connected across said gap for intermittently applying pulses thereto of a voltage insufficient to effect breakdown in said gap in the absence of smoke particles in the ambient air but sufficient to cause such breakdown in the presence of smoke particles; and detector means connected to said gap and responsive to the breakdown thereof for producing a warning signal.
Claim 26
Dependent Claim
30 words
The system defined in claim 20 wherein said source has an output frequency of 0.01 to 10 Hz and produces pulses of a pulse width of 1 to 100 microseconds.
Claim 27
Dependent Claim
51 words
The system defined in claim 20 wherein said source includes a low-voltage dry-cell or battery, an oscillator operated thereby and a stepup transformer having a primary winding operatively connected with the output of said oscillator and a secondary winding connected in circuit with said gap for applying thereto said voltage pulses.
Claim 28
Dependent Claim
17 words
The system defined in claim 20 wherein said gap has a width of 0.1 to 1 mm.
Claim 29
Dependent Claim
27 words
The system defined in claim 20 wherein said electrode means includes a bimetal element deflectable by temperature rise to bridge said gap and operate said detector means.
Claim 30
Dependent Claim
38 words
The system defined in claim 20 wherein said detector means includes a resistor in circuit with said gap and a transistor network bridged across said resistor for changing its state in response to the passage of current therethrough.
Claim 31
Dependent Claim
26 words
The system defined in claim 20 wherein said detector means includes an oscillator energized upon breakdown of said gap and transducer means energizable by said oscillator.
Claim 32
Dependent Claim
50 words
The system defined in claim 26 wherein said detector means further includes locking means for maintaining said oscillator in oscillation once gap breakdown is detected to continue energization of said transducer independently of gap voltage, and switch means associated with said locking means for terminating the operation of said oscillator.
Claim 33
Dependent Claim
26 words
The system defined in claim 20, further comprising a printed circuit board, said detector means, said source and said electrode means being mounted on said board.
Claim 34
Independent Claim
107 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a gap bridged by ambient air and including a pointed electrode poled as cathodic and a planar electrode poled as anodic; a voltage source connected across said gap for applying a potential thereto to measure gap conductivity across said electrodes variable in the absence and the presence of smoke particles in the air bridging said gap; and detector means connected to said electrodes across said gap and responsive to the gap conductivity for producing a warning signal upon detection of a gap conductivity indicative of the presence Of smoke particles in said gap.
Claim 35
Independent Claim
107 words
A system for warning of a smoke or fire condition, comprising: electrode means forming a gap bridged by ambient air and including a pointed electrode poled as cathodic and a planar electrode poled as anodic; a voltage source connected across said gap for applying a potential thereto to measure gap conductivity across said electrodes variable in the absence and the presence of smoke particles in the air bridging said gap; and detector means connected to said electrodes across said gap and responsive to the gap conductivity for producing a warning signal upon detection of a gap conductivity indicative of the presence Of smoke particles in said gap.
Claim 36
Dependent Claim
29 words
A system as defined in claim 29 wherein at least one of said electrodes is formed with bimetallic member for shifting said electrodes relatively upon a change in temperature.
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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) | 1977-04-15 | 1977-10-15 | 1978-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-15 | 1981-10-15 | 1982-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-15 | 1985-10-15 | 1986-04-16 | $7700.00 | Window Closed / Lapsed |