GB350519A - Improvements in or relating to electrical burglar alarm apparatus - Google Patents

Improvements in or relating to electrical burglar alarm apparatus

Info

Publication number
GB350519A
GB350519A GB694730A GB694730A GB350519A GB 350519 A GB350519 A GB 350519A GB 694730 A GB694730 A GB 694730A GB 694730 A GB694730 A GB 694730A GB 350519 A GB350519 A GB 350519A
Authority
GB
United Kingdom
Prior art keywords
thread
contact
spring
burglar alarm
carrying
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
GB694730A
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to GB694730A priority Critical patent/GB350519A/en
Publication of GB350519A publication Critical patent/GB350519A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/02—Mechanical actuation
    • G08B13/12—Mechanical actuation by the breaking or disturbance of stretched cords or wires
    • G08B13/126—Mechanical actuation by the breaking or disturbance of stretched cords or wires for a housing, e.g. a box, a safe, or a room
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/02—Mechanical actuation
    • G08B13/12—Mechanical actuation by the breaking or disturbance of stretched cords or wires
    • G08B13/122—Mechanical actuation by the breaking or disturbance of stretched cords or wires for a perimeter fence

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Burglar Alarm Systems (AREA)
  • Operating, Guiding And Securing Of Roll- Type Closing Members (AREA)

Abstract

350,519. Burglar alarms. LEWIN, E., 31B, Luisenstrasse, Berlin. March 3, 1930, No. 6947. [Class 118 (i).] A burglar alarm is given by the closing or opening of an electric circuit when a taut thread is disturbed suddenly. The thread 16 passes round a pulley 4 carrying a forked contact 13 and connected by a spring 7 to a wheel 6 carrying the other contact 14, so that only sudden movements of the thread cause relative movements of the contacts. Cutting of the thread releases a spring- urged auxiliary contact 18 to give the alarm. When the device is housed in a wall, the contact 18 is replaced by a contact device which is closed or opened by a spring-controlled drum on which the thread is wound. An arrangement of threads for operation by the sudden movement of revolving shutters is described.
GB694730A 1930-03-03 1930-03-03 Improvements in or relating to electrical burglar alarm apparatus Expired GB350519A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB694730A GB350519A (en) 1930-03-03 1930-03-03 Improvements in or relating to electrical burglar alarm apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB694730A GB350519A (en) 1930-03-03 1930-03-03 Improvements in or relating to electrical burglar alarm apparatus

Publications (1)

Publication Number Publication Date
GB350519A true GB350519A (en) 1931-06-04

Family

ID=9823755

Family Applications (1)

Application Number Title Priority Date Filing Date
GB694730A Expired GB350519A (en) 1930-03-03 1930-03-03 Improvements in or relating to electrical burglar alarm apparatus

Country Status (1)

Country Link
GB (1) GB350519A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2151060A (en) * 1983-10-30 1985-07-10 Israel Aircraft Ind Ltd Taut wire fence system
US7887028B2 (en) * 2001-09-18 2011-02-15 Gallagher Group Limited Electric fence

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2151060A (en) * 1983-10-30 1985-07-10 Israel Aircraft Ind Ltd Taut wire fence system
US4730809A (en) * 1983-10-30 1988-03-15 Israel Aircraft Industries Ltd. Taut wire fence system
US7887028B2 (en) * 2001-09-18 2011-02-15 Gallagher Group Limited Electric fence

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