Patent · US Expired

Lock with removable cylinder

US5775146A · kind A · utility

10Cited by
17References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 7, 1995
Grant dateJul 7, 1998
Priority date
Expiry dateJun 7, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T70/7695
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A key lock tumbler cylinder is selectively removed with an extraction key that is longer than a normal operating key. The last tumbler plate in a tabular cylinder series along the cylinder key slot projects into an arcuate channel in the cylinder cavity wall of the lock body. This arcuate channel does not junction with the lock tumbler plate channel but does intersect with a second channel in the cavity wall that is angularly displaced about the cylinder axis from the tumbler plate channel. However, the second channel is more shallow than the arcuate channel to confine the tumbler cylinder within the body cavity when rotated by the operating key which does not engage the last tumbler plate key aperture. A second, tumbler cylinder extraction key that is longer than the operating key includes an edge bit at the end of the key for cooperating with the last tumbler plate key aperture. This end of the extraction key withdraws the last tumbler plate from the arcuate channel sufficiently to allow a tabular extension from the last tumbler plate blade to align with the second channel when the tumbler cylinder is rotated about the cylinder axis from the tumbler plate channel penetration posi…

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