FR831810A - Improvements to electrical alarm systems - Google Patents
Improvements to electrical alarm systemsInfo
- Publication number
- FR831810A FR831810A FR831810DA FR831810A FR 831810 A FR831810 A FR 831810A FR 831810D A FR831810D A FR 831810DA FR 831810 A FR831810 A FR 831810A
- Authority
- FR
- France
- Prior art keywords
- alarm systems
- electrical alarm
- electrical
- systems
- alarm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B17/00—Fire alarms; Alarms responsive to explosion
- G08B17/06—Electric actuation of the alarm, e.g. using a thermally-operated switch
Landscapes
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Emergency Alarm Devices (AREA)
- Emergency Protection Circuit Devices (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE2249891X | 1937-01-09 |
Publications (1)
Publication Number | Publication Date |
---|---|
FR831810A true FR831810A (en) | 1938-09-15 |
Family
ID=20425109
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FR831810D Expired FR831810A (en) | 1937-01-09 | 1938-01-08 | Improvements to electrical alarm systems |
Country Status (3)
Country | Link |
---|---|
US (1) | US2249891A (en) |
DE (1) | DE732994C (en) |
FR (1) | FR831810A (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2636163A (en) * | 1951-04-19 | 1953-04-21 | Earle V Gardiner | Burglar alarm system |
US3401234A (en) * | 1965-04-16 | 1968-09-10 | Rimac Ltd | Combined audio program and alarm signaling system with line supervision |
GB1123607A (en) * | 1965-12-28 | 1968-08-14 | American District Telegraph Co | Electrical protection system |
US4529316A (en) * | 1982-10-18 | 1985-07-16 | Robotic Vision Systems, Inc. | Arrangement of eliminating erroneous data in three-dimensional optical sensors |
-
1937
- 1937-11-07 DE DEE50380D patent/DE732994C/en not_active Expired
-
1938
- 1938-01-08 US US184100A patent/US2249891A/en not_active Expired - Lifetime
- 1938-01-08 FR FR831810D patent/FR831810A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
US2249891A (en) | 1941-07-22 |
DE732994C (en) | 1943-03-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
FR836633A (en) | Antenna systems | |
FR49159E (en) | Improvements to signaling systems | |
FR844373A (en) | Improvements to frequency-selective electrical systems | |
FR939004A (en) | Improvements to antenna systems | |
FR847855A (en) | Improvements to aerial systems | |
FR831620A (en) | Improvements to telephone systems | |
FR839635A (en) | Radio-electric systems | |
FR831810A (en) | Improvements to electrical alarm systems | |
FR836831A (en) | Improvements to direction-finding installations | |
FR858896A (en) | Improvements to electro-magnetic systems | |
FR832277A (en) | Improvements to automatic alarm systems | |
FR835343A (en) | Improvements to electrical systems | |
FR840325A (en) | Improvements to telephone systems | |
FR847653A (en) | Amplifier systems | |
FR49158E (en) | Improvements to telephone systems | |
FR846979A (en) | Improvements to television systems | |
FR847279A (en) | Improvements to telephone systems | |
FR838511A (en) | Improvements to telephone systems | |
FR832760A (en) | Improvements to telegraph systems | |
FR931429A (en) | Improvements to radio-telegraph systems | |
FR834007A (en) | Improvements to electrical signaling systems | |
FR836656A (en) | Improvements to electrical signaling systems | |
FR857679A (en) | Improvements to electrical alarm devices | |
FR844408A (en) | Improvements to telecommunication systems | |
FR843767A (en) | Electrical amplifier systems |