Self-locking key-controlled door lock
US4138869A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 26, 1977 |
| Grant date | Feb 13, 1979 |
| Priority date | — |
| Expiry date | Sep 26, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T292/0994
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A flush-mountable, key-controlled, handle-operated door lock is provided with an automatic self-locking linkage for permitting the handle to move once, but only once, out of a nested position after a key control has been operated to "cock" the linkage. Once the linkage has been cocked, the handle can be moved one time out of and returned to its nested position, whereafter the linkage operates to retain the handle in its nested position until the key control is again operated to cock the linkage. The automatic latching linkage includes a housing assembly, a pair of cams, and a pair of springs. A feature of the automatic latching linkage is that its several components can be assembled easily on an existing, in-service lock to provide the existing lock with a one-trip automatic locking capability. The latching linkage components are assembled by installing the components one at a time in an essentially stacked arrangement, one atop the other. The simple assembly steps required can be carried out even where accessibility to the rearward face of an in-service lock is quite limited.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.