Patent · US Expired

Key control device and method therefor

US5372021A · kind A · utility

36Cited by
22References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 30, 1992
Grant dateDec 13, 1994
Priority date
Expiry dateOct 30, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T70/7768
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A key control device comprises a primary key, a primary lock, a secondary key, a secondary lock, and a mechanical drive. The primary lock operably receives the primary key and is keyed such that when the primary key is inserted into the primary lock, it becomes movable between a primary key release state and a primary key capture state. The secondary lock operably receives the secondary key and is keyed such that when the secondary key is received by the secondary lock it becomes movable between a secondary key release state and a secondary key capture state. The mechanical drive interconnects the primary and secondary locks such that when the primary lock moves from its primary key release state to its primary key capture state, the secondary lock simultaneously moves from its secondary key capture state to its secondary key release state and vice versa. Only one key can be removed at any given time from either lock and such removal locks the other key against removal so that it is retained by the key control device.

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