Lock cylinder with variable keyway profile
US5502991A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 12, 1994 |
| Grant date | Apr 2, 1996 |
| Priority date | — |
| Expiry date | Jul 12, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T70/8595
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The lock cylinder comprises a cylinder body wherein a cylinder plug (1) comprising a slot (2) for the key (18) of the lock is rotatable arranged. The profile of the key slot and therefore also of the key is determined by profile forming elements in the form of rotation bodies (6,7) which are inserted in bores (4,5) extending through the cylinder plug (1) parallel to and adjacent to the middle plane (10) of the key slot (2). The profile elements (6,7) may be made of hardenable steel, for instance by turning, and may comprise a number of portions of different diameters so that the total number of key profiles obtainable becomes high while permitting the key profile to be made very thin and correspondingly difficult to copy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.