Key-removable lock core
US4424693A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1980 |
| Grant date | Jan 10, 1984 |
| Priority date | — |
| Expiry date | Nov 5, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T70/765
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A key-removable core for a lock chamber of figure-8 cross section has a short cylindrical key plug housing fitting the lower lobe of the chamber and a pin tumbler housing containing a series of pin tumbler barrels, two of which are in an extension beyond the key plug housing. A key plug is contained in such housing and a control sleeve aligned with such housing beneath the extension and having pin tumbler bores aligned with said two barrels. Side faces on the pin tumbler housing and spaced from the chamber side wall provide clearance on one side for a retaining lug on the control sleeve retractable into such clearance from core-retaining engagement behind a shoulder in the chamber, and clearance on the other side for a stop lug. An operating key aligns tumblers in all barrels for shear movement at an operating shear line at the outer surface of the key plug. A control key aligns tumblers in the two extension-contained barrels for shear movement at a control shear line at the outer surface of the control sleeve, and tumblers in the other barrels for shear movement at the operating shear line, to permit rotation of the sleeve to retract its retaining lug. The pin tumbler housing may …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.