GB599813A - Improvements relating to signalling means for use in telephone systems - Google Patents

Improvements relating to signalling means for use in telephone systems

Info

Publication number
GB599813A
GB599813A GB270345A GB270345A GB599813A GB 599813 A GB599813 A GB 599813A GB 270345 A GB270345 A GB 270345A GB 270345 A GB270345 A GB 270345A GB 599813 A GB599813 A GB 599813A
Authority
GB
United Kingdom
Prior art keywords
telephone
relay
substation
central station
alarm
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
GB270345A
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.)
HERBERT SANG HUGHES
Original Assignee
HERBERT SANG HUGHES
Filing date
Publication date
Application filed by HERBERT SANG HUGHES filed Critical HERBERT SANG HUGHES
Publication of GB599813A publication Critical patent/GB599813A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B27/00—Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations
    • G08B27/001—Signalling to an emergency team, e.g. firemen
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B27/00—Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations
    • G08B27/006—Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations with transmission via telephone network

Landscapes

  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Alarm Systems (AREA)

Abstract

599,813. Substation equipment. HUGHES. H. S. Feb. 21, 1946, No. 2703/45. [Class 40 (iv)] In a system for use in an unattended fire substation or the like, upon a call being received from a central office, alarm bells are rung in the domiciles of the firemen until a receiver is lifted from a telephone in the substation. In the Figure, terminals a represent an extension of the bell circuit of one telephone and b similar terminals of another telephone 14 each connected to the central station. To sound the alarm, the central station rings on the first telephone and follows immediately by a ring on the second telephone. Relay c responds to the first ring and operates pendulum relay n which remains operated sufficiently long to allow ringing current from the second telephone to operate p. This relay energizes coil u to pull over armature 3 to complete the circuit for the alarm bells at contact 4 and also completes a circuit for relay 10 which effects the changes in the telephone 14 normally brought about by lifting the handset, so that ringing of the station alarm may be heard by the central station over the second telephone. A person arriving at the substation lifts the handset from the cradle switch 2 of the telephone 14 so energizing at contact z the coil w to return armature 3 to normal and at contact z1 to maintain relay 10 operated so that conversation with the central station may take place.
GB270345A 1946-02-21 Improvements relating to signalling means for use in telephone systems Expired GB599813A (en)

Publications (1)

Publication Number Publication Date
GB599813A true GB599813A (en) 1948-03-22

Family

ID=1627423

Family Applications (1)

Application Number Title Priority Date Filing Date
GB270345A Expired GB599813A (en) 1946-02-21 Improvements relating to signalling means for use in telephone systems

Country Status (1)

Country Link
GB (1) GB599813A (en)

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