US3678487A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-zone incipient or actual fire and/or dangerous gas detection system
Assignee: Environment One Corp
•
Filing: 1971-02-08
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Granted: 1972-07-18
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Expires: 1991-02-08
Abstract
Abstract A multi-zone detecting system for incipient or actual fires and/or dangerous gas accumulations comprising a multi-zone sampling system for obtaining samples of the atmosphere of the respective zones being monitored and supplying the same to a common sampling station. The sample gases are continuously drawn off and supplied through a rotary selector valve sequentially to the input of a common condensation nuclei particle detector located at the common sampling station. The sensitivity of the condensation nuclei detector is individually adjusted in synchronism with the operation of the rotary selector valve to adjust the sensitivity of the condensation nuclei detector to the individual background conditions existing in each zone being monitored as the detector is sequentially switched from one zone to the next. The sensitivity of the common condensation nuclei detector is decreased for a predetermined short time settling interval following each sequential switching operation prior to making a measurement with respect to the sample atmosphere of the new zone to which it is switched. A gas conversion device can be interposed in the input to the common condensation nuclei detector for converting certain dangerous gases that might be entrained in the sample atmospheres from the several zones into condensation nuclei for supply and analysis by the condensation nuclei detector. With such an arrangement, the concentration of condensation nuclei particles detected would be in proportion to the dangerous gas constituency of the sample atmospheres. A continuous flow sample system provides a relatively fast responding detection of the occurrence of an alarm condition in any of the several zones being monitored. Additional advantageous features are described.
Inventors
- 👤 Frederick A Ludewig Jr
- 👤 Frank W Van Luik Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:39
CPC Classifications
G; G08; G08B; G08B17/00; G08B17/10; G08B17/103; G08B17/107; G01; G01N; G01N15/00; G01N15/06; G01N15/065
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
126 words
A multi-zone detecting system comprising a multi-zone sampling system for obtaining samples of the atmosphere of the respective zones being monitored and supplying the same to a common sampling station, a common detector located at the common detection station for detecting the existence of an alarm condition in any of the zones and deriving an output indication of the alarm condition, selective supply means coupled to the multi-zone sampling system and to the common detector for sequentially supplying the samples from the respective zones to the common detector, and sensitivity adjusting means coupled to the common detector as it is sequentially switched from one zone to the next whereby the response of the detector is individually adjusted to background conditions existing in each zone being monitored.
Claim 2
Dependent Claim
126 words
A multi-zone detecting system comprising a multi-zone sampling system for obtaining samples of the atmosphere of the respective zones being monitored and supplying the same to a common sampling station, a common detector located at the common detection station for detecting the existence of an alarm condition in any of the zones and deriving an output indication of the alarm condition, selective supply means coupled to the multi-zone sampling system and to the common detector for sequentially supplying the samples from the respective zones to the common detector, and sensitivity adjusting means coupled to the common detector as it is sequentially switched from one zone to the next whereby the response of the detector is individually adjusted to background conditions existing in each zone being monitored.
Claim 3
Dependent Claim
51 words
A multi-zone detecting system according to claim 1 further including means for desensitizing the common detector for a pre-determined settling time during each sequential switching of the input to the common detector whereby a short time interval settling period is provided prior to monitoring the samples from each of the zones.
Claim 4
Dependent Claim
52 words
A multi-zone detecting system according to claim 1 wherein the common detector comprises a condensation nuclei detector for detecting condensation nuclei particles present in the atmospheres of the respective zones being monitored and for deriving an output indication of the presence of condensation nuclei particles in excess of a given background amount.
Claim 5
Dependent Claim
45 words
A multi-zone detecting system according to claim 3 further including gas conversion means interposed in the input to the condensation nuclei detector for converting dangerous gases entrained in the sample atmospheres from the several zones into condensation nuclei for supply to the condensation nuclei detector.
Claim 6
Dependent Claim
54 words
A multi-zone detecting system according to claim 1 further including time-controlled sensitivity adjusting means for further adjusting the sensitivity of the common detector in accordance with a predetermined timed program whereby compensation can be provided for different background conditions at different times such as different day and night operations in the zones being monitored.
Claim 7
Dependent Claim
83 words
A multi-zone detecting system according to claim 1 wherein the selective supply means comprises continuous flow supply means for providing a continuous flow of the sample atmospheres from the respective zones being monitored, and selector valve means operable in conjunction with the continuous flow supply means for sequentially selecting on-the-fly from the continuous flowing streams samples of the atmospheres from the respective zones for supply to the common detector whereby response of the overall detecting system to an alarm condition is speeded up.
Claim 8
Dependent Claim
89 words
A multi-zone detecting system according to claim 6 wherein said selector valve means is a multiple input port rotary selector valve having a common output port and is located at the common sampling station input valve and includes individually flow adjusting means for each of the input ports whereby the continuous flow of sample atmosphere from the respective zones being monitored can be individually adjusted to compensate for differences in length of flow path and the like to thereby balance flow of the sample atmospheres to the common detector.
Claim 9
Dependent Claim
46 words
A multi-zone detecting system according to claim 7 wherein the design of the selector valve means readily can be modified to accommodate different sampling periods, multiple sampling of particular zones and the like in accordance with the requirements of a particular multi-zone installation to be monitored.
Claim 10
Dependent Claim
51 words
A multi-zone detecting system according to claim 8 further including means for desensitizing the common detector for a pre-determined settling time during each sequential switching of the input to the common detector whereby a short time interval settling period is provided prior to monitoring the sample from each of the zones.
Claim 11
Dependent Claim
123 words
A multi-zone detecting system according to claim 9 wherein the common detector comprises a condensation nuclei detector for detecting condensation nuclei particles present in the atmospheres of the respective zones being monitored and for deriving an output signal inDicative of the presence of condensation nuclei particles in excess of a given background amount, said condensation nuclei detector having output signal amplifying means for amplifying the output signal and wherein said sensitivity adjusting means comprises gain change circuit means coupled to the output signal amplifying means for changing the gain of the output signal amplifying means synchronously with the switching of the zones being monitored whereby the sensitivity of the detecting system is individually adjusted to background conditions existing in each zone being monitored.
Claim 12
Dependent Claim
43 words
A multi-zone detecting system according to claim 10 further including gas conversion means selectively connectable to the input of the condensation nuclei detector for converting dangerous gases entrained in the sample atmospheres selectively supplied from the several zones into condensation nuclei for measurements.
Claim 13
Dependent Claim
56 words
A multi-zone detecting system according to claim 10 further including time controlled sensitivity adjusting means for further adjusting the sensitivity of the output amplifying means in accordance with a predetermined time program whereby compensation can be provided for different background conditions at different times such as different day and night operations in the zones being monitored.
Claim 14
Dependent Claim
62 words
A multi-zone detecting system according to claim 10 further including flow sensing means disposed in the respective paths of the sampling system for sensing the respective flow rates and deriving output control signal in accordance therewith, and means supplying the respective control signals to the alarm circuitry to signal the existence of a malfunction where the flow rates drop below predetermined values.
Claim 15
Dependent Claim
82 words
A multi-zone detecting system according to claim 10 wherein the means for desensitizing the common detector for a predetermined interval of time during each sequential switching of the common detector to sample the respective zones being monitored comprises cam operated switch means operated synchronously with rotary selector valve for deriving a desensitizing electric signal that is applied to the common detector to render it unresponsive to alarm conditions for a predetermined settling interval following each switching operation by the rotary selector valve.
Claim 16
Dependent Claim
62 words
A multi-zone detecting system according to claim 14 further including fail-safe relay operated indicating means for each of the several zones being monitored by the detecting system and responsive to the output signal from the output signal amplifying means of the condensation nuclei detector for indicating the existence of an alarm condition in any of the zones being monitored in fail-safe manner.
Claim 17
Dependent Claim
51 words
A multi-zone detecting system according to claim 15 further including fail-safe malfunction indicating means responsive to the output of the condensation nuclei detector means for indicating the existence of a malfunction in a fail-safe manner upon the output from the condensation nuclei detector means dropping below a predetermined minimum reference level.
Claim 18
Dependent Claim
55 words
A multi-zone detecting system according to claim 1 further including fail-safe malfunction indicating means responsive to the output from the common detector for indicating the existence of a malfunction condition in any of the zones being monitored in a fail-safe manner upon the output from the common detector dropping below a predetermined minimum reference level.
Claim 19
Dependent Claim
73 words
A multi-zone detecting system according to claim 1 further including flow sensing means disposed in the respective paths of the sampling system for sensing the respective flow rates and deriving output control signals representative of the respective flow rates, and means supplying the respective control signals to the common detector for adjusting the sensitivity of the common detector in accordance with the flow rate of the sample atmosphere supplied from the respective zones.
Claim 20
Dependent Claim
115 words
A multi-zone detecting system according to claim 1 further including fail-safe relay operated inDicating means for each of the several zones being monitored by the detecting system and responsive to the output from the common detector for indicating the existence of an alarm condition in any of the zones being monitored in a fail-safe manner, fail-safe malfunction detector means responsive to the output from the common detector means for indicating the existence of a malfunction condition in the detecting system in a fail-safe manner, and wherein the common detector and indicating arrangement have relatively small electric power requirements whereby the entire system can be operated on standby battery power during emergency periods of power failure.
Claim 21
Independent Claim
104 words
A method of monitoring a plurality of different zones for the detection of incipient or actual fires and/or dangerous gas accumulation comprising sequentially supplying a sample of the atmosphere in each zone being monitored to a common measuring station, measuring each sample sequentially at the common measurement station to detect and signal the existence of an alarm condition in any of the zones being monitored, and adjusting the sensitivity of each sample measurement sequentially in synchronization with the supply of sample atmospheres as measurement is switched from one zone to another in accordance with the individual background conditions existing in each zone being monitored.
Claim 22
Independent Claim
104 words
A method of monitoring a plurality of different zones for the detection of incipient or actual fires and/or dangerous gas accumulation comprising sequentially supplying a sample of the atmosphere in each zone being monitored to a common measuring station, measuring each sample sequentially at the common measurement station to detect and signal the existence of an alarm condition in any of the zones being monitored, and adjusting the sensitivity of each sample measurement sequentially in synchronization with the supply of sample atmospheres as measurement is switched from one zone to another in accordance with the individual background conditions existing in each zone being monitored.
Claim 23
Dependent Claim
34 words
A method according to claim 20 further including desensitizing the sample measurement for a short duration settling period following each sequential switching of a sample atmosphere from one zone being monitored to the next.
Claim 24
Dependent Claim
33 words
A method according to claim 21 wherein the sample measurement is obtained by deriving a measurement of the condensation nuclei particle concentration present in the sample gaseous atmosphere of each zone being monitored.
Claim 25
Dependent Claim
61 words
A method according to claim 22 further including converting gaseous contituents entrained in the atmosphere of the zones being monitored into condensation nuclei particles whose concentration is representative of the proportion of the gaseous contituents present in the atmosphere and then measuring the condensation nuclei particle concentration as an indication of the proportion of gaseous constituents entrained in the sample atmosphere.
Claim 26
Dependent Claim
46 words
A method according to claim 20 further including adjusting the sensitivity of the sample measurement in accordance with the time of day and the nature of operations being conducted in the respective zones being monitored where such operations change in accordance with the time of day.
Claim 27
Dependent Claim
64 words
A method according to claim 20 wherein sample atmospheres from all of the zones being monitored are continuously drawn from each of the respective zones and supplied to the common sample measurement station where the respective sample atmospheres are sequentially accessed on-the-fly and measured in a predetermined sequential order whereby the response time of the monitoring method to an alarm condition is greatly improved.
Claim 28
Dependent Claim
45 words
A method according to claim 25 further comprising separately adjusting the flow rate of the respective sample atmospheres to the measuring operation in order to balance the flow rates and improve response of the measurement only to changes in conditions in the zones being monitored.
Claim 29
Dependent Claim
30 words
A method according to claim 26 wherein the sampling rate and/or the duration of sampling of certain zones is different due to the different nature of the zones being monitored.
Claim 30
Dependent Claim
34 words
A method according to claim 25 further including desensitizing the sample measurement for a short duration settling period following each sequential switching of a sample atmosphere from one zone being monitored to the next.
Claim 31
Dependent Claim
33 words
A method according to claim 28 wherein the sample measurement is obtained by deriving a measurement of the condensation nuclei particle concentration present in the sample gaseous atmosphere of each zone being monitored.
Claim 32
Dependent Claim
63 words
A method according to claim 29 further including converting certain gaseous constituents entrained in the atmospheRe of the zones being monitored into condensation nuclei particles whose concentration is representative of the proportion of the gaseous constituents present in the atmosphere and then measuring the condensation nuclei particle concentration as an indication of the proportion of the gaseous constituents entrained in the sample atmospheres.
Claim 33
Dependent Claim
46 words
A method according to claim 29 further including adjusting the sensitivity of the sample measurements in accordance with the time of day and the nature of operations being conducted in the respective zones being monitored where such operation change in accordance with the time of day.
Claim 34
Dependent Claim
34 words
A method according to claim 29 further including measuring the output from the condensation nuclei detector continuously and signaling the existence of a malfunction condition upon the output dropping below a predetermined minimum level.
Claim 35
Dependent Claim
46 words
A method according to claim 29 further including indicating the existence of an alarm condition in any of the zones being monitored or a malfunction in a fail-safe manner whereby upon the occurrence of a power failure, malfunction or the like an output alarm is indicated.
Claim 36
Dependent Claim
36 words
A method according to claim 20 further including sensing the flow rate of the sample atmospheres from the different zones being monitored and signalling a malfunction condition where the flow rate falls below a predetermined standard.
References Cited (Backward Citations)
US3618061A
Cited
US3588481A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |