US3295121A - Electric alarm system, preferably for fire alarms - Google Patents

Electric alarm system, preferably for fire alarms Download PDF

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Publication number
US3295121A
US3295121A US247694A US24769462A US3295121A US 3295121 A US3295121 A US 3295121A US 247694 A US247694 A US 247694A US 24769462 A US24769462 A US 24769462A US 3295121 A US3295121 A US 3295121A
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US
United States
Prior art keywords
chambers
radiating member
ionizing
voltage
chamber
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 - Lifetime
Application number
US247694A
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English (en)
Inventor
Meyer Svend Scheel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Danske Securitas AS
Original Assignee
Danske Securitas AS
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Danske Securitas AS filed Critical Danske Securitas AS
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Publication of US3295121A publication Critical patent/US3295121A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00—Fire alarms; Alarms responsive to explosion
    • G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
    • G08B17/11—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using an ionisation chamber for detecting smoke or gas
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
    • G01N15/06—Investigating concentration of particle suspensions
    • G01N15/0656—Investigating concentration of particle suspensions using electric, e.g. electrostatic methods or magnetic methods
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/62—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode
    • G01N27/64—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode using wave or particle radiation to ionise a gas, e.g. in an ionisation chamber
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
    • G01T7/00—Details of radiation-measuring instruments
    • G01T7/12—Provision for actuation of an alarm
    • G01T7/125—Alarm- or controlling circuits using ionisation chambers, proportional counters or Geiger-Mueller tubes, also functioning as UV detectors

Definitions

  • the internal resistances of the ionizing chambers will normally determine the direct voltage across each of the two voltage-dependent capacitors of the voltage divider, whereas a variation in the internal resistance of the open ionizing chamber will produce a variation in the direct voltage of the capacitor connected in parallel with this chamber, which will involve a substantial non-balance in the normally balanced bridge arrangement, whereby the system becomes very sensitive to particles of smoke or liquid entering the open ionizing chamber.
US247694A 1961-12-30 1962-12-27 Electric alarm system, preferably for fire alarms Expired - Lifetime US3295121A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DK526361AA DK101900C (da) 1961-12-30 1961-12-30 Elektrisk alarmanlæg, fortrinsvis til brandalarmering.

Publications (1)

Publication Number Publication Date
US3295121A true US3295121A (en) 1966-12-27

Family

ID=8140940

Family Applications (1)

Application Number Title Priority Date Filing Date
US247694A Expired - Lifetime US3295121A (en) 1961-12-30 1962-12-27 Electric alarm system, preferably for fire alarms

Country Status (6)

Country Link
US (1) US3295121A (xx)
AT (2) AT250834B (xx)
CH (1) CH397472A (xx)
DK (1) DK101900C (xx)
GB (1) GB1020771A (xx)
SE (1) SE309180B (xx)

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3514603A (en) * 1966-12-22 1970-05-26 Johnson Service Co Ionization chamber detection apparatus having a low voltage source means
US3676678A (en) * 1969-04-25 1972-07-11 Nittan Co Ltd Single chamber ionization smoke detector
US3728703A (en) * 1970-10-12 1973-04-17 Edward Co Inc Fire detector stabilizer circuit
US3987423A (en) * 1975-12-22 1976-10-19 The United States Of America As Represented By The United States Energy Research And Development Administration Ionization-chamber smoke detector system
US4012729A (en) * 1975-06-19 1977-03-15 Statitrol Corporation Multi-element ionization chamber
US4023152A (en) * 1973-10-01 1977-05-10 Matsushita Electric Works, Ltd. Ionization type smoke sensing device
US4222046A (en) * 1978-07-31 1980-09-09 Honeywell Inc. Abnormal condition responsive means with periodic high sensitivity
US4245174A (en) * 1978-04-24 1981-01-13 Isotec Industries Limited Dual ionization chamber
US4280052A (en) * 1978-11-09 1981-07-21 Solomon Elias E Multiple chamber ionization detector
US4364031A (en) * 1979-12-14 1982-12-14 Cerberus Ag Ionization smoke detector with increased operational reliability
WO2013090322A1 (en) * 2011-12-14 2013-06-20 Microchip Technology Incorporated Method and apparatus for detecting smoke in an ion chamber
US20130154657A1 (en) * 2011-12-14 2013-06-20 Microchip Technology Incorporated Method and Apparatus for Detecting Smoke in an ION Chamber
US8847802B2 (en) 2011-10-06 2014-09-30 Microchip Technology Incorporated Microcontroller ADC with a variable sample and hold capacitor
US8884771B2 (en) 2012-08-01 2014-11-11 Microchip Technology Incorporated Smoke detection using change in permittivity of capacitor air dielectric
US9071264B2 (en) 2011-10-06 2015-06-30 Microchip Technology Incorporated Microcontroller with sequencer driven analog-to-digital converter
US9207209B2 (en) 2011-12-14 2015-12-08 Microchip Technology Incorporated Method and apparatus for detecting smoke in an ion chamber
US9252769B2 (en) 2011-10-07 2016-02-02 Microchip Technology Incorporated Microcontroller with optimized ADC controller
US9257980B2 (en) 2011-10-06 2016-02-09 Microchip Technology Incorporated Measuring capacitance of a capacitive sensor with a microcontroller having digital outputs for driving a guard ring
US9437093B2 (en) 2011-10-06 2016-09-06 Microchip Technology Incorporated Differential current measurements to determine ION current in the presence of leakage current
US9467141B2 (en) 2011-10-07 2016-10-11 Microchip Technology Incorporated Measuring capacitance of a capacitive sensor with a microcontroller having an analog output for driving a guard ring
US9823280B2 (en) 2011-12-21 2017-11-21 Microchip Technology Incorporated Current sensing with internal ADC capacitor

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE30323E (en) * 1968-09-26 1980-07-01 Hochiki Kabushiki Kaisha Smoke detector adapted to a smoke sensing apparatus

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1991934A (en) * 1929-09-23 1935-02-19 Harry F Mccray Apparatus and process for utilizing emanations from radio-active material
US2646556A (en) * 1950-06-17 1953-07-21 C O Two Fire Equipment Co Supervised alarm system
US2702898A (en) * 1953-10-06 1955-02-22 Electro Watt Electrical And In Gas-responsive control apparatus
US2759174A (en) * 1952-08-26 1956-08-14 American District Telegraph Co Fire detector
GB831812A (en) * 1957-02-01 1960-03-30 Minerva Detector Company Ltd Improvements in or relating to fire detectors

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1991934A (en) * 1929-09-23 1935-02-19 Harry F Mccray Apparatus and process for utilizing emanations from radio-active material
US2646556A (en) * 1950-06-17 1953-07-21 C O Two Fire Equipment Co Supervised alarm system
US2759174A (en) * 1952-08-26 1956-08-14 American District Telegraph Co Fire detector
US2702898A (en) * 1953-10-06 1955-02-22 Electro Watt Electrical And In Gas-responsive control apparatus
GB831812A (en) * 1957-02-01 1960-03-30 Minerva Detector Company Ltd Improvements in or relating to fire detectors

Cited By (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3514603A (en) * 1966-12-22 1970-05-26 Johnson Service Co Ionization chamber detection apparatus having a low voltage source means
US3676678A (en) * 1969-04-25 1972-07-11 Nittan Co Ltd Single chamber ionization smoke detector
US3728703A (en) * 1970-10-12 1973-04-17 Edward Co Inc Fire detector stabilizer circuit
US4023152A (en) * 1973-10-01 1977-05-10 Matsushita Electric Works, Ltd. Ionization type smoke sensing device
US4012729A (en) * 1975-06-19 1977-03-15 Statitrol Corporation Multi-element ionization chamber
US3987423A (en) * 1975-12-22 1976-10-19 The United States Of America As Represented By The United States Energy Research And Development Administration Ionization-chamber smoke detector system
US4245174A (en) * 1978-04-24 1981-01-13 Isotec Industries Limited Dual ionization chamber
US4222046A (en) * 1978-07-31 1980-09-09 Honeywell Inc. Abnormal condition responsive means with periodic high sensitivity
US4280052A (en) * 1978-11-09 1981-07-21 Solomon Elias E Multiple chamber ionization detector
US4364031A (en) * 1979-12-14 1982-12-14 Cerberus Ag Ionization smoke detector with increased operational reliability
EP0030621B1 (de) * 1979-12-14 1985-01-16 Cerberus Ag Ionisationsrauchmelder mit erhöhter Betriebssicherheit
US9805572B2 (en) 2011-10-06 2017-10-31 Microchip Technology Incorporated Differential current measurements to determine ion current in the presence of leakage current
US9437093B2 (en) 2011-10-06 2016-09-06 Microchip Technology Incorporated Differential current measurements to determine ION current in the presence of leakage current
US9071264B2 (en) 2011-10-06 2015-06-30 Microchip Technology Incorporated Microcontroller with sequencer driven analog-to-digital converter
US9257980B2 (en) 2011-10-06 2016-02-09 Microchip Technology Incorporated Measuring capacitance of a capacitive sensor with a microcontroller having digital outputs for driving a guard ring
US8847802B2 (en) 2011-10-06 2014-09-30 Microchip Technology Incorporated Microcontroller ADC with a variable sample and hold capacitor
US9467141B2 (en) 2011-10-07 2016-10-11 Microchip Technology Incorporated Measuring capacitance of a capacitive sensor with a microcontroller having an analog output for driving a guard ring
US9252769B2 (en) 2011-10-07 2016-02-02 Microchip Technology Incorporated Microcontroller with optimized ADC controller
WO2013090327A1 (en) * 2011-12-14 2013-06-20 Microchip Technology Incorporated Method and apparatus for detecting smoke in an ion chamber
US9176088B2 (en) * 2011-12-14 2015-11-03 Microchip Technology Incorporated Method and apparatus for detecting smoke in an ion chamber
US9189940B2 (en) * 2011-12-14 2015-11-17 Microchip Technology Incorporated Method and apparatus for detecting smoke in an ion chamber
US9207209B2 (en) 2011-12-14 2015-12-08 Microchip Technology Incorporated Method and apparatus for detecting smoke in an ion chamber
CN104094328A (zh) * 2011-12-14 2014-10-08 密克罗奇普技术公司 用于检测离子室中的烟雾的方法及设备
CN104067324A (zh) * 2011-12-14 2014-09-24 密克罗奇普技术公司 用于检测离子室中的烟雾的方法及设备
US20130154657A1 (en) * 2011-12-14 2013-06-20 Microchip Technology Incorporated Method and Apparatus for Detecting Smoke in an ION Chamber
US20130154670A1 (en) * 2011-12-14 2013-06-20 Microchip Technology Incorporated Method and Apparatus for Detecting Smoke in an ION Chamber
CN104094328B (zh) * 2011-12-14 2016-11-09 密克罗奇普技术公司 用于检测离子室中的烟雾的方法及设备
CN104067324B (zh) * 2011-12-14 2016-11-16 密克罗奇普技术公司 用于检测离子室中的烟雾的方法及设备
WO2013090322A1 (en) * 2011-12-14 2013-06-20 Microchip Technology Incorporated Method and apparatus for detecting smoke in an ion chamber
US9823280B2 (en) 2011-12-21 2017-11-21 Microchip Technology Incorporated Current sensing with internal ADC capacitor
US8884771B2 (en) 2012-08-01 2014-11-11 Microchip Technology Incorporated Smoke detection using change in permittivity of capacitor air dielectric

Also Published As

Publication number Publication date
CH397472A (de) 1965-08-15
GB1020771A (en) 1966-02-23
AT248300B (de) 1966-07-25
DK101900C (da) 1965-06-08
SE309180B (xx) 1969-03-10
AT250834B (de) 1966-11-25

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