US4792797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Smoke detector having variable level sensitivity
Assignee: Bank of America Illinois
•
Filing: 1987-03-05
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Granted: 1988-12-20
•
Expires: 2007-03-05
Abstract
Abstract A smoke detector having variable sensitivity to smoke levels and using one button both to test the smoke detector and actuate a mode of diminished sensitivity to smoke levels. The smoke detector is operable in a normal sensitivity mode and a diminished sensitivity mode with rapid switching between the modes. The sensitivity to smoke levels is substantially constant when in either the normal or diminished sensitivity mode.
Inventors
- 👤 William P. Tanguay
- 👤 James McCrink
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:31
CPC Classifications
G; G08; G08B; G08B17/00; G08B17/10; G08B29/00; G08B29/12; G08B29/14; G08B29/145
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
102 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a single user actuaed element adapted to cause generation of said alarm signal; and means for temporarily diminishing the sensitivity of said smoke detector by increasing in said sensing means the magnitude of said predetermined smoke level causing generation of said alarm signal, said single user element further adapted to actuate said diminishing means.
Claim 2
Dependent Claim
102 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a single user actuaed element adapted to cause generation of said alarm signal; and means for temporarily diminishing the sensitivity of said smoke detector by increasing in said sensing means the magnitude of said predetermined smoke level causing generation of said alarm signal, said single user element further adapted to actuate said diminishing means.
Claim 3
Dependent Claim
26 words
The smoke detector as defined in claim 1 wherein said sensing means comprises at least one of an ionization chamber/radioactive source and a photoelectric sensor system.
Claim 4
Dependent Claim
117 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; and means for temporarily diminishing the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke level causing generation of said alarm signal, said user actuated element further adapted to actuate said diminishing means and said user testing means overriding the operation of said diminishing means during the operation of said testing means.
Claim 5
Dependent Claim
117 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; and means for temporarily diminishing the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke level causing generation of said alarm signal, said user actuated element further adapted to actuate said diminishing means and said user testing means overriding the operation of said diminishing means during the operation of said testing means.
Claim 6
Dependent Claim
127 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means operable by the user for generating an alarm signal output to said alarm signal means; and means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means the magnitude of said predetermined smoke level causing generation of said alarm signal, said diminishing means generating a control signal for establishing the increased magnitude of said predetermined smoke level, and said control signal having a substantially constant magnitude during said temporary time period.
Claim 7
Dependent Claim
127 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means operable by the user for generating an alarm signal output to said alarm signal means; and means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means the magnitude of said predetermined smoke level causing generation of said alarm signal, said diminishing means generating a control signal for establishing the increased magnitude of said predetermined smoke level, and said control signal having a substantially constant magnitude during said temporary time period.
Claim 8
Dependent Claim
137 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means operable by the user for generating an alarm signal output to said alarm signal means; and means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means the magnitude of said predetermined smoke level causing generation of said alarm signal, said diminishing means generating a control signal over said temporary time period and said control signal having a slowly changing level until the end of said temporary time period whereupon said control signal decays rapidly causing deactivation of said diminishing means.
Claim 9
Dependent Claim
137 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means operable by the user for generating an alarm signal output to said alarm signal means; and means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means the magnitude of said predetermined smoke level causing generation of said alarm signal, said diminishing means generating a control signal over said temporary time period and said control signal having a slowly changing level until the end of said temporary time period whereupon said control signal decays rapidly causing deactivation of said diminishing means.
Claim 10
Dependent Claim
31 words
The smoke detector as defined in claim 5 wherein said diminishing means comprises at least means for amplifying a small current input and having a large gain and small current output.
Claim 11
Dependent Claim
25 words
The smoke detector as defined in claim 5 wherein said increased predetermined smoke sensitivity level comprises a moderate smoke level associated with user generated conditions.
Claim 12
Dependent Claim
32 words
The smoke detector as defined in claim 7 wherein said user generated conditions comprise at least one of cooking smoke, fireplace smoke, excessive water vapor and persons smoking cigarettes, cigars or pipes.
Claim 13
Dependent Claim
124 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke sensitivity level causing generation of said alarm signal, said user element being a single element and adapted to both actuate said diminishing means and operate said testing means; and sensitivity control means for user selection of said increased predetermined smoke level.
Claim 14
Dependent Claim
124 words
A smoke detector comprising: means for sensing smoke levels and generating a signal charcteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke sensitivity level causing generation of said alarm signal, said user element being a single element and adapted to both actuate said diminishing means and operate said testing means; and sensitivity control means for user selection of said increased predetermined smoke level.
Claim 15
Dependent Claim
17 words
The smoke detector as defined in claim 9 wherein said alarm signal means comprises a voltage comparator.
Claim 16
Dependent Claim
13 words
The smoke detector as defined in claim 10 further including alarm generating means.
Claim 17
Dependent Claim
20 words
The smoke detector as defined in claim 11 wherein said alarm generating means comprises a horn and light emitting diode.
Claim 18
Dependent Claim
50 words
The apparatus as defined in claim 1 wherein said alarm signal means remains quiet unless user tested or said smoke levels exceed said increased predetermined smoke level during operation of said diminishing means or said smoke levels exceed said predetermined smoke level during the normal operation of said smoke detector.
Claim 19
Dependent Claim
23 words
The apparatus as defined in claim 1 further including means for inhibiting operation of said diminishing means for a user selected time period.
Claim 20
Dependent Claim
96 words
A smoke detector comprising: means for sensing smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; and means for temporarily diminishing the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke level causing generation of said alarm signal, said user testing means overriding the operation of said diminishing means during the operation of said testing means.
Claim 21
Dependent Claim
96 words
A smoke detector comprising: means for sensing smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; and means for temporarily diminishing the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke level causing generation of said alarm signal, said user testing means overriding the operation of said diminishing means during the operation of said testing means.
Claim 22
Dependent Claim
140 words
A smoke detector having a normal sensitivity level and a moderate sensitivity level, comprising: means for sensing smoke levels and generating a signal characteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means operable by the user for generating an alarm signal output to said alarm signal means; and means for diminishing for a temporary time period the sensitivity of said smoke detector to said moderate sensitivity level for activating said alarm signal, and said dminishing means generating a control signal having a slowly changing magnitude during said temporary time period and a rapidly changing magnitude at the end of said temporary time period, whereupon the sensitivity of said smoke detector returns to said normal level.
Claim 23
Dependent Claim
140 words
A smoke detector having a normal sensitivity level and a moderate sensitivity level, comprising: means for sensing smoke levels and generating a signal characteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means operable by the user for generating an alarm signal output to said alarm signal means; and means for diminishing for a temporary time period the sensitivity of said smoke detector to said moderate sensitivity level for activating said alarm signal, and said dminishing means generating a control signal having a slowly changing magnitude during said temporary time period and a rapidly changing magnitude at the end of said temporary time period, whereupon the sensitivity of said smoke detector returns to said normal level.
Claim 24
Dependent Claim
124 words
A smoke detector comprising: means for sensing smoke levels and generating a signal characteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke sensitivity level causing generation of said alarm signal, said user element being a single element and adapted to both actuate said diminishing means and operate said testing means; and sensitivity control means for user selection of said increased predetermined smoke level.
Claim 25
Dependent Claim
124 words
A smoke detector comprising: means for sensing smoke levels and generating a signal characteristic of said smoke levels; means for generating an alarm signal responsive to said sensing means detecting a predetermined smoke level; means for user testing the operability of said smoke detector, said testing means comprising a user actuated element adapted to cause generation of said alarm signal; means for diminishing for a temporary time period the sensitivity of said smoke detector by increasing in said sensing means said predetermined smoke sensitivity level causing generation of said alarm signal, said user element being a single element and adapted to both actuate said diminishing means and operate said testing means; and sensitivity control means for user selection of said increased predetermined smoke level.
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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) | 1991-12-20 | 1992-06-20 | 1992-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-20 | 1996-06-20 | 1996-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-20 | 2000-06-20 | 2000-12-20 | $7700.00 | Window Closed / Lapsed |