GB1308242A - Ionization smoke detecting system - Google Patents

Ionization smoke detecting system

Info

Publication number
GB1308242A
GB1308242A GB2639970A GB2639970A GB1308242A GB 1308242 A GB1308242 A GB 1308242A GB 2639970 A GB2639970 A GB 2639970A GB 2639970 A GB2639970 A GB 2639970A GB 1308242 A GB1308242 A GB 1308242A
Authority
GB
United Kingdom
Prior art keywords
thyristor
potential
generator
chambers
smoke
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
GB2639970A
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
Application filed by Nittan Co Ltd filed Critical Nittan Co Ltd
Publication of GB1308242A publication Critical patent/GB1308242A/en
Expired legal-status Critical Current

Links

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

Landscapes

  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Fire-Detection Mechanisms (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

1308242 Testing ionization smoke detectors NITTAN CO Ltd 1 June 1970 [2 June 1969, 11 Sept 1969 4 Oct 1969(2)] 26399/70 Headings G1N and G1U [Also in Division H3] The invention is concerned with testing smoke detectors Fig. 1 of the kind comprising open and closed ionization chambers 10, 20 connected in series across a voltage supply 4, 5 such that when smoke enters the open chamber 20 the potential 1 between the two chambers rises to increase conduction through an f. e.t. 3, causing a zener diode 8 to break down and fire a thyristor 7. Such smoke detectors are modified by the provision of a switch 15 to isolate the electrode 21 of chamber 20, and are tested by applying an increasing potential to electrode 21 and detecting when the thyristor 7 fires as a result of the consequent increase in the potential 1 between the chambers. The testing apparatus Fig. 3 comprises a generator 26 of the increasing voltage and a relay 28 in series with a supply 25 for the smoke detector. When the thyristor 7 fires one contact 42 of relay 28 closes to light a lamp 56 whilst another contact 41 opens to prevent further increase in the output of generator 26, the generator output being measured on a meter 29.
GB2639970A 1969-06-02 1970-06-01 Ionization smoke detecting system Expired GB1308242A (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP4252669 1969-06-02
JP7158669 1969-09-11
JP7897469 1969-10-04
JP7897569 1969-10-04

Publications (1)

Publication Number Publication Date
GB1308242A true GB1308242A (en) 1973-02-21

Family

ID=27461210

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2639970A Expired GB1308242A (en) 1969-06-02 1970-06-01 Ionization smoke detecting system

Country Status (3)

Country Link
US (1) US3657713A (en)
GB (1) GB1308242A (en)
NL (1) NL147269B (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3702468A (en) * 1970-08-10 1972-11-07 Nittan Co Ltd Fire alarming system
CA1148279A (en) * 1979-12-14 1983-06-14 Andreas Scheidweiler Ionization smoke detector with increased operational reliability
JPS6017157B2 (en) * 1981-02-25 1985-05-01 ニツタン株式会社 Selective actuatable fire detector
US4481502A (en) * 1982-03-26 1984-11-06 Dawson N Rick Central smoke alarm and annunciator
US4538137A (en) * 1983-01-20 1985-08-27 Nittan Company, Limited Fire detector
US4595914A (en) * 1983-04-11 1986-06-17 Pittway Corporation Self-testing combustion products detector
US6501810B1 (en) 1998-10-13 2002-12-31 Agere Systems Inc. Fast frame synchronization
US5546074A (en) * 1993-08-19 1996-08-13 Sentrol, Inc. Smoke detector system with self-diagnostic capabilities and replaceable smoke intake canopy
US7489136B1 (en) * 2005-08-04 2009-02-10 Nu-Trek, Inc. Apparatus and method of detecting radiation
JP4446290B2 (en) * 2006-03-02 2010-04-07 日立工機株式会社 Electric tools and tabletop cutting machines

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH380594A (en) * 1960-11-02 1964-07-31 Securiton Ag Ionization fire alarm system
JPS446089Y1 (en) * 1966-03-30 1969-03-05

Also Published As

Publication number Publication date
NL147269B (en) 1975-09-15
DE2027064B2 (en) 1972-06-22
NL7007956A (en) 1970-12-04
DE2027064A1 (en) 1971-01-21
US3657713A (en) 1972-04-18

Similar Documents

Publication Publication Date Title
GB1308242A (en) Ionization smoke detecting system
GB1163121A (en) Improvements in and relating to Fire Alarm Apparatus.
CA959179A (en) Smoke detector with at least one smoke measuring chamber
SE7710961L (en) SECURITY DEVICE
GB1295498A (en)
GB1347306A (en) Fire detector
ES415905A1 (en) Ionization-type fire sensor
GB1306394A (en)
ES444964A1 (en) Ionization detector
GB1320489A (en) Fire alarm system
ES412625A1 (en) Radioactive halogen monitoring system
FR2366563A1 (en) SMOKE DETECTOR
GB1394642A (en) Electrical alarm instruments
GB1215814A (en) Ionization chamber detection apparatus.
GB1259437A (en)
SE389570B (en) FIRE FIGHTING DEVICE WITH AN AIR AVAILABLE IONIZATION CHAMBER
YU314380A (en) Ionization signalization device of smoke with higher operation reliability
GB1260984A (en) Ionization smoke detector
ES361790A1 (en) Flame detector
GB1253196A (en)
GB1313877A (en) Smoke detectors
FR2386874A1 (en) IONIZATION SMOKE DETECTOR ASSOCIATED WITH AN ELECTRONIC VELOCIMETRIC MEASUREMENT CIRCUIT
GB1299326A (en) Ionization smoke detectors
GB1381475A (en) Apparatus for detecting smoke and like suspensions
ES350324A1 (en) Ionization fire detection device

Legal Events

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