Patent · US Expired

Double cylinder lock with key retention

US4228669A · kind A · utility

22Cited by
9References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 3, 1978
Grant dateOct 21, 1980
Priority date
Expiry dateJul 3, 1998

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T70/7768
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A double cylinder lock constructed with a single tailpiece driver and a clutch. The interior lock key can be extracted only when the lock bolt is retracted and not when the lock bolt is extended. The driver and clutch arrangement prevent either cylinder from becoming out of time, regardless of which cylinder is used to throw the bolt.

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