Patent · US Expired

Combination locks with electro-optical silent alarm system

US4455552A · kind A · utility

12Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 24, 1981
Grant dateJun 19, 1984
Priority date
Expiry dateNov 24, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T70/7424
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A combination lock of the dial operated tumbler wheel type comprising lock mechanism components including a fence lever and rotatable members to be rotatably positioned responsive to rotation of a dial, the rotatable members including peripherally gated tumbler wheels and a drive cam driven from the dial, and electro-optical light sensing and electrical signalling means for producing sensible indications at a remote monitoring station signifying movement of components of the combination lock mechanism. This means comprises a marking having optically distinctive reflectivity properties on a component of the lock mechanism such as the driving cam and/or a tumbler wheel and/or the fence lever and optical sensor means positioned to receive light from the optically distinctive marking electrical signal signifying movement of the optically distinctive marking.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.