GB1299326A - Ionization smoke detectors - Google Patents

Ionization smoke detectors

Info

Publication number
GB1299326A
GB1299326A GB04433/71A GB1443371A GB1299326A GB 1299326 A GB1299326 A GB 1299326A GB 04433/71 A GB04433/71 A GB 04433/71A GB 1443371 A GB1443371 A GB 1443371A GB 1299326 A GB1299326 A GB 1299326A
Authority
GB
United Kingdom
Prior art keywords
fet
electrodes
smoke detectors
scr
portions
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
GB04433/71A
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.)
Nittan Co Ltd
Original Assignee
Nittan Co Ltd
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
Priority claimed from JP4911170A external-priority patent/JPS4840318B1/ja
Priority claimed from JP7453270A external-priority patent/JPS4911800B1/ja
Application filed by Nittan Co Ltd filed Critical Nittan Co Ltd
Publication of GB1299326A publication Critical patent/GB1299326A/en
Expired legal-status Critical Current

Links

Classifications

    • 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
    • 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
    • G08B17/113—Constructional details

Landscapes

  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Emergency Management (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Business, Economics & Management (AREA)
  • Pathology (AREA)
  • Toxicology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Immunology (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Molecular Biology (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Electrochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Fire-Detection Mechanisms (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)

Abstract

1299326 Smoke detectors NITTAN CO Ltd 12 May 1971 [8 June 1970 27 Aug 1970] 14433/71 Heading G1N [Also in Division H1] In an ionisation smoke detector the common electrodes of two series connected, open and closed ionisation chambers 20, 10 are divided into two portions 131, 132 and 231, 232, the common junctions of the portions being respectively connected to the gate electrodes of FET's 31, 32. The source electrodes of FET's 31, 32 are repesectively connected, via Zener diodes 71, 72, to the control electrodes of SCR's 41, 42 connected in series between the supply so that if one of the FET's operates erroneously an alarm is not given. By connecting a pair of Zener diodes in parallel with the SCR's, Fig.3 (not shown), the erroneous FET may be detected.
GB04433/71A 1970-06-08 1971-05-12 Ionization smoke detectors Expired GB1299326A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP4911170A JPS4840318B1 (en) 1970-06-08 1970-06-08
JP7453270A JPS4911800B1 (en) 1970-08-27 1970-08-27

Publications (1)

Publication Number Publication Date
GB1299326A true GB1299326A (en) 1972-12-13

Family

ID=26389475

Family Applications (1)

Application Number Title Priority Date Filing Date
GB04433/71A Expired GB1299326A (en) 1970-06-08 1971-05-12 Ionization smoke detectors

Country Status (4)

Country Link
US (1) US3775616A (en)
CA (1) CA927022A (en)
FR (1) FR2095675A5 (en)
GB (1) GB1299326A (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4109240A (en) * 1973-11-26 1978-08-22 Cerberus Ag. Ionization-type fire sensing system
US3944859A (en) * 1974-09-03 1976-03-16 Rca Corporation Bridge-balance detection circuit
CH597659A5 (en) * 1976-02-06 1978-04-14 Cerberus Ag
US4176311A (en) * 1976-12-23 1979-11-27 General Electric Company Positive ion smoke detector using a tungsten wire preheated in hydrogen to increase sensitivity
JPH0530236Y2 (en) * 1987-10-05 1993-08-02

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH446131A (en) * 1966-02-22 1967-10-31 Cerberus Ag Ionization fire alarm system
JPS446089Y1 (en) * 1966-03-30 1969-03-05
US3513311A (en) * 1968-02-29 1970-05-19 Fike Metal Prod Corp Radiation sensitive apparatus for activating a fire or explosion protection system
US3541539A (en) * 1968-11-29 1970-11-17 Us Air Force Integrated fire and overheat detection system for manned flight vehicles

Also Published As

Publication number Publication date
CA927022A (en) 1973-05-22
DE2128477B2 (en) 1972-07-27
FR2095675A5 (en) 1972-02-11
US3775616A (en) 1973-11-27
DE2128477A1 (en) 1971-12-09

Similar Documents

Publication Publication Date Title
OA02414A (en) Door locking and sealing system.
GB1295498A (en)
GB1299326A (en) Ionization smoke detectors
GB1109587A (en) Improvements in or relating to ionization smoke detectors
BE771465A (en) SAMPLING VALVE, AND COMPOUND DETECTION SYSTEM
DK122549B (en) Smoke detector with a visual function monitoring control.
GB1215814A (en) Ionization chamber detection apparatus.
GB1280298A (en) Improvements in and relating to combustion detectors
GB1259437A (en)
GB1299234A (en) Ionization smoke detector
GB1248762A (en) Security container
GB1278925A (en) Ionization smoke detector
GB1300909A (en) Ionization smoke detector
GB1282536A (en) Ionization smoke detectors
GB1273307A (en) Ionization smoke detector
GB1277091A (en) Ionization type smoke detectors
GB1271768A (en) Alarm device
DK116228B (en) Particle detector, in particular smoke detector, with a double-acting monitoring circuit.
GB1103457A (en) Improvements in and relating to signal devices
GB1364720A (en) Ionization type smoke sensing device
GB1512545A (en) Ionisation fire sensors
GB1275450A (en) Ionization smoke detecting device
GB1280431A (en) Fire detector
GB1308873A (en) Ionization smoke detectors
GB1315602A (en) Fire alarm system

Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PCNP Patent ceased through non-payment of renewal fee