Pin tumbler lock with pull-resistant key plug
US4294093A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 1979 |
| Grant date | Oct 13, 1981 |
| Priority date | — |
| Expiry date | Jun 14, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T70/8568
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A key-removable lock core of the same size as a standard core, to fit standard core receptacles, and having a key plug of improved pull resistance. The core body of figure-8 cross section has a key plug lobe which contains a sleeve having a core retainer lug movable by a control key between a projected core retaining position and a retracted core release position. A key plug having an enlarged rear head is inserted from the rear into the cylindrical bore defined by the sleeve, with the head overlapping the rear of both the sleeve and the key plug lobe of the body. A segment is inserted in a slot traversing the key slot and is trapped therein by the sleeve to form a key stop. The key plug is held in place by a C-shaped retaining ring in a circumferential groove in such plug at the front face of the body, and is trapped in place by a face plate fixed to the body by a blind annular rivet. Beside increasing the plug pull resistance, the construction gives improved dimensional control and accuracy of assembly and eliminates a previously required step of counterboring the face plate after its assembly to the core body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.