GB835933A - Improvements in and relating to apparatus for detecting carbon monoxide - Google Patents

Improvements in and relating to apparatus for detecting carbon monoxide

Info

Publication number
GB835933A
GB835933A GB1188157A GB1188157A GB835933A GB 835933 A GB835933 A GB 835933A GB 1188157 A GB1188157 A GB 1188157A GB 1188157 A GB1188157 A GB 1188157A GB 835933 A GB835933 A GB 835933A
Authority
GB
United Kingdom
Prior art keywords
measuring
thermistors
april
carbon monoxide
adjusted
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
GB1188157A
Inventor
Reginald Valentine
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.)
Coal Industry Patents Ltd
Original Assignee
Coal Industry Patents 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 Coal Industry Patents Ltd filed Critical Coal Industry Patents Ltd
Priority to GB1188157A priority Critical patent/GB835933A/en
Publication of GB835933A publication Critical patent/GB835933A/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
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/14—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of an electrically-heated body in dependence upon change of temperature
    • G01N27/16—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of an electrically-heated body in dependence upon change of temperature caused by burning or catalytic oxidation of surrounding material to be tested, e.g. of gas

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

835,933. Electric measuring systems. COAL INDUSTRY (PATENTS) Ltd. April 11; 1958 [April 11, 1957], No. 11881/57. Addition to 756,662. Class 40 (1). [Also in Group XL (c)] The apparatus for the determination of the percentage carbon monoxide in an atmosphere described in the parent Specification by measuring the temperature difference between two: thermistors each in the atmosphere, one of the thermistors being also located in contact with an oxidizer, the teinperature difference being determined by measuring the change in resistance, is modified by using transistors instead of thermionic valves in the electrical circuits, with additional ambient temperature compensation. As shown, a transistor oscillator T1 has a large degree of negative feed-back between base and emitter, and positive feed-back via a transformer TT1 sufficient to saturate the transistor on the negative swing and to cut it off on the positive swing, to produce a rectangular output voltage between zero and a maximum value determined by emitter resistors R4, R5, R6 selected by switch SW1a, and adjusted by potentiometer VR1. The. oscillator feeds through a buffer stage T2 to a bridge incorporating the measuring thermistors 4, 5. The bridge unbalance voltage is amplified by transistors T3, T4, whose gain is adjusted by potentiometers VR2, VR3 to differ from optimum in a sense to compensate for variation in sensitivity with temperature, and rectified at MR, to be shown on a meter M1, and to control an audible alarm PH and visual alarm WL via relay winding RL.
GB1188157A 1957-04-11 1957-04-11 Improvements in and relating to apparatus for detecting carbon monoxide Expired GB835933A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1188157A GB835933A (en) 1957-04-11 1957-04-11 Improvements in and relating to apparatus for detecting carbon monoxide

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1188157A GB835933A (en) 1957-04-11 1957-04-11 Improvements in and relating to apparatus for detecting carbon monoxide

Publications (1)

Publication Number Publication Date
GB835933A true GB835933A (en) 1960-05-25

Family

ID=9994386

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1188157A Expired GB835933A (en) 1957-04-11 1957-04-11 Improvements in and relating to apparatus for detecting carbon monoxide

Country Status (1)

Country Link
GB (1) GB835933A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1203022B (en) * 1960-12-15 1965-10-14 English Electric Co Ltd Device for the detection of small amounts of a flammable gas in a gas atmosphere
US3221320A (en) * 1961-04-13 1965-11-30 Komyo Rikagaku Kogyo Kabushiki Gas alarm circuit

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1203022B (en) * 1960-12-15 1965-10-14 English Electric Co Ltd Device for the detection of small amounts of a flammable gas in a gas atmosphere
US3221320A (en) * 1961-04-13 1965-11-30 Komyo Rikagaku Kogyo Kabushiki Gas alarm circuit

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