Patent · US Expired

Key for a lock cylinder

US4787225A · kind A · utility

88Cited by
8References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 18, 1986
Grant dateNov 29, 1988
Priority date
Expiry dateNov 18, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T70/787
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

For increased security the key (2; 40; 44) has one or more blade portions (43; 45; 46; 5, 6). The longitudinal central plane (A, B) of the or each blade portion is offset from the guide region (42; 7) running along the back edge of the key shaft (3). Furthermore, the or each blade portion is connected to the guide region by means of a bridging portion (14, 14') which forms an obtuse angle (alpha) with the guide region, as well as forming an obtuse angle with the blade portion. In one preferred embodiment two blade portions (45, 46; 5, 6) are provided; they may be of the same cross-sectional shape (FIG. 2) or symmetrical (FIG. 11). The blade portions and guide region may be divided into two portions to provide partner keys (FIG. 12).

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