GB1172353A - Improvements relating to Smoke Detectors - Google Patents

Improvements relating to Smoke Detectors

Info

Publication number
GB1172353A
GB1172353A GB6900/66A GB690066A GB1172353A GB 1172353 A GB1172353 A GB 1172353A GB 6900/66 A GB6900/66 A GB 6900/66A GB 690066 A GB690066 A GB 690066A GB 1172353 A GB1172353 A GB 1172353A
Authority
GB
United Kingdom
Prior art keywords
voltage
thyristor
transistor
lamp
arrangement
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
GB6900/66A
Inventor
Edward William Lines
William Thomas Peberdy
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.)
Pyrene Co Ltd
Original Assignee
Pyrene 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 Pyrene Co Ltd filed Critical Pyrene Co Ltd
Priority to GB6900/66A priority Critical patent/GB1172353A/en
Publication of GB1172353A publication Critical patent/GB1172353A/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
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/0004—Gaseous mixtures, e.g. polluted air
    • G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
    • G01N33/0062—General constructional details of gas analysers, e.g. portable test equipment concerning the measuring method, e.g. intermittent, or the display, e.g. digital
    • G01N33/0063—General constructional details of gas analysers, e.g. portable test equipment concerning the measuring method, e.g. intermittent, or the display, e.g. digital using a threshold to release an alarm or displaying means
    • 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
    • G08B17/103—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device
    • G08B17/107—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device for detecting light-scattering due to smoke
    • 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

Abstract

1,172,353. Transistor switching circuits. PYRENE CO. Ltd. 16 Feb., 1967 [16 Feb., 1966], No. 6900/66. Heading H3T. [Also in Divisions G1 and G4] A smoke detector circuit, Fig. 1, is provided with a thermistor T for temperature compensation and includes the lamp L1 and the photocell, a photo-resistor RV, whose output may be amplified (by transistor TR1) before being applied to the triggering electrode of a thyristor, e.g. silicon controlled rectifier SCR1. Voltage stabilization is provided by transistor TR2 together with resistor R4 and Zener diode Z2, and protection of the thyristor against transients by capacitors C1, C2. When an increase of light on photo-cell RV is sufficient such that the voltage across R2 reaches the sum of the voltage set by Zener. diode Z1 plus the firing voltage of the SCR, the latter is switched on and current flows in signal line 5 to light lamp L2 and energize device 6. The signal current may, in an alternative arrangement, be added to the line current or be detected by a transformer having a further thyristor in its secondary circuit which is fired in the event of smoke detection. A lamp failure, indicated by a decrease in line current, may also be indicated using this arrangement. A number of smoke detectors may share the same alarm system when this arrangement is used. Specification 1,172,354, which claims the feature of using a thermistor in series with the light source, is referred to.
GB6900/66A 1966-02-16 1966-02-16 Improvements relating to Smoke Detectors Expired GB1172353A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB6900/66A GB1172353A (en) 1966-02-16 1966-02-16 Improvements relating to Smoke Detectors

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB6900/66A GB1172353A (en) 1966-02-16 1966-02-16 Improvements relating to Smoke Detectors

Publications (1)

Publication Number Publication Date
GB1172353A true GB1172353A (en) 1969-11-26

Family

ID=9822868

Family Applications (1)

Application Number Title Priority Date Filing Date
GB6900/66A Expired GB1172353A (en) 1966-02-16 1966-02-16 Improvements relating to Smoke Detectors

Country Status (1)

Country Link
GB (1) GB1172353A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0055319A1 (en) * 1980-12-30 1982-07-07 COMPAGNIE CENTRALE SICLI (Société Anonyme) Smoke detector of the light diffusion type with self-checking
GB2137390A (en) * 1983-03-07 1984-10-03 Emhart Ind Sensor assembly
US5231378A (en) * 1990-06-23 1993-07-27 Kidde-Graviner Limited Particle detection which senses scattered light
CN111263958A (en) * 2017-10-30 2020-06-09 开利公司 Compensator in detector device

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0055319A1 (en) * 1980-12-30 1982-07-07 COMPAGNIE CENTRALE SICLI (Société Anonyme) Smoke detector of the light diffusion type with self-checking
GB2137390A (en) * 1983-03-07 1984-10-03 Emhart Ind Sensor assembly
US5231378A (en) * 1990-06-23 1993-07-27 Kidde-Graviner Limited Particle detection which senses scattered light
CN111263958A (en) * 2017-10-30 2020-06-09 开利公司 Compensator in detector device
CN111263958B (en) * 2017-10-30 2022-05-27 开利公司 Compensator in detector device

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Legal Events

Date Code Title Description
PS Patent sealed
PLNP Patent lapsed through nonpayment of renewal fees