US4644331A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fire alarm system
Assignee: Hochiki Corp
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Filing: 1985-06-18
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Granted: 1987-02-17
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Expires: 2005-06-18
Abstract
Abstract The detection signals regarding the temperature or smoke concentration generated due to the fire are sampled. The sampled data is processed by being averaged. An occurrence of a fire is determined on the basis of the processed data, i.e. - the averaged data, after completion of the averaging processes. The detection signals which are used for the fire determined are obtained by performing a moving mean calculation of a plurality of sampled data as one group and/or by executing a simple mean calculation of a plurality of moving mean data as one group.
Inventors
- 👤 Eige Matsushita
- 👤 Tetsuya Nagashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:40
CPC Classifications
G; G08; G08B; G08B29/00; G08B29/18
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
97 words
A fire alarm system comprising: a detecting section for detecting and outputting an analog value corresponding to a change in a physical phenomenon of the ambient circumstances; sampling means for sampling at a predetermined period the analog detection signal outputted from said detecting section; data processing means for sequentially storing sampled data from said sampling means and for performing an averaging process of a plurality of said data stored as one group; and an alarm means for discriminating a fire on the basis of averaged data from said data processing means and then generating a fire alarm.
Claim 2
Dependent Claim
97 words
A fire alarm system comprising: a detecting section for detecting and outputting an analog value corresponding to a change in a physical phenomenon of the ambient circumstances; sampling means for sampling at a predetermined period the analog detection signal outputted from said detecting section; data processing means for sequentially storing sampled data from said sampling means and for performing an averaging process of a plurality of said data stored as one group; and an alarm means for discriminating a fire on the basis of averaged data from said data processing means and then generating a fire alarm.
Claim 3
Dependent Claim
51 words
A fire alarm system according to claim 1, wherein said data processing means has: first memory means for sequentially storing a plurality of said sampled data; and moving mean calculating means for calculating a moving mean of a plurality of said data stored as one group in said first memory means.
Claim 4
Dependent Claim
90 words
A fire alarm system according to claim 1, wherein said data processing means has: first memory means for storing a plurality of said sampled data; moving mean calculating means for calculating a moving mean of a plurality of said data stored as one group in said first memory means; second memory means for storing a plurality of moving means for said moving mean calculating means; and simple mean calculating means for calculating a simple mean of said plurality of moving means stored as one group in said second memory means.
Claim 5
Dependent Claim
92 words
A fire alarm system according to claim 1, wherein said data processing means has: first memory means for storing a plurality of said sampled data; moving mean calculating means for calculating a moving mean of a plurality of said data stored as one group in said first memory means; second memory means for storing a plurality of moving means from said moving mean calculating means; and another moving mean calculating means for calculating a moving mean of a plurality of said moving means stored as one group in said second memory means.
Claim 6
Dependent Claim
60 words
A fire alarm system according to claim 1, wherein said alarm means has fire discriminating means for calculating, from the present time averaged data from said data processing means, a time interval until a value of the averaged data would reach a predetermined threshold level and thereby determining the fire when said time interval calculated lies within a predetermined time.
Claim 7
Dependent Claim
60 words
A fire alarm system according to claim 1, wherein said alarm means has a fire discriminating means for determining that a fire has occurred when a detection level exceeds a threshold level after an expiration of a predetermined time period from the commencement of the processing of data on the basis of the averaged data from said data processing means.
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) | 1990-02-16 | 1990-08-18 | 1991-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-16 | 1994-08-18 | 1995-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-16 | 1998-08-18 | 1999-02-17 | $7700.00 | Window Closed / Lapsed |