GB1054089A - - Google Patents

Info

Publication number
GB1054089A
GB1054089A GB1054089DA GB1054089A GB 1054089 A GB1054089 A GB 1054089A GB 1054089D A GB1054089D A GB 1054089DA GB 1054089 A GB1054089 A GB 1054089A
Authority
GB
United Kingdom
Prior art keywords
circuit
thermistor
oct
depicts
capacitance
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
Application number
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.)
Publication date
Publication of GB1054089A publication Critical patent/GB1054089A/en
Expired legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C3/00—Fire prevention, containment or extinguishing specially adapted for particular objects or places
    • A62C3/06—Fire prevention, containment or extinguishing specially adapted for particular objects or places of highly inflammable material, e.g. light metals, petroleum products
    • 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
    • G01N27/66—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 and measuring current or voltage
    • 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
    • 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

Landscapes

  • Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Analytical Chemistry (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Toxicology (AREA)
  • Public Health (AREA)
  • General Chemical & Material Sciences (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Molecular Biology (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Electrochemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Fire-Detection Mechanisms (AREA)
  • Photometry And Measurement Of Optical Pulse Characteristics (AREA)

Abstract

1,054,089. Detecting fires electrically. ANSTALT POUR APPLICATIONS ELECTRONIQUES. Oct.14, 1964 [Oct. 16, 1963], No. 41850/64. Heading G1N. [Also in Divisions G4 and H3] In a fire detector, the voltage across an ionization chamber E whose interior is accessible to the atmosphere controls the capacitance of a diode C p , the variations of which capacitance actuate an indicator device. As shown in Fig. 4, a stabilized crystal oscillator feeds an oscillatory circuit comprising L 1 , C 1 and C p . L 2 is inductively coupled with L 1 and feeds an amplifier α and a demodulator # to supply a signal dependent on the amplitude of the oscillations in the circuit L 1 , C 1 , C p to a load V which may be an electromagnetic or solid state relay, a thyratron, a radio transmitter or any other information or alarm system. Fig. 5 (not shown) depicts a simplified circuit. Fig. 6 (not shown), depicts a circuit which may be used to provide extra information to reduce the risk of false alarms. A relay L 3 is actuated if the temperature of a thermistor Th 1 is too high and/or if infrared radiation falls on an infrared sensitive photo-cell or an open base transistor with an optical filter P 1 and/or if the temperature of an exposed thermistor Th 3 exceeds that of a shielded thermistor Th 2 . Thermistors Th 4, Fig. 6, and R 5 , Fig. 4, are used to stabilize transistor T 2 and the crystal oscillator respectively. Resistance R may be a second ionisation chamber.
GB1054089D 1963-10-16 Expired GB1054089A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
LU44637 1963-10-16

Publications (1)

Publication Number Publication Date
GB1054089A true GB1054089A (en) 1900-01-01

Family

ID=19723529

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1054089D Expired GB1054089A (en) 1963-10-16

Country Status (4)

Country Link
CH (1) CH432305A (en)
FR (1) FR1420444A (en)
GB (1) GB1054089A (en)
LU (1) LU44637A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2158312A (en) * 1984-04-28 1985-11-06 Smith Meters Ltd Transistor circuits

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2158312A (en) * 1984-04-28 1985-11-06 Smith Meters Ltd Transistor circuits

Also Published As

Publication number Publication date
LU44637A1 (en) 1963-12-16
CH432305A (en) 1967-03-15
FR1420444A (en) 1965-12-10

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