Mechanical/electronic lock and key
US5552777A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 1994 |
| Grant date | Sep 3, 1996 |
| Priority date | — |
| Expiry date | Nov 21, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T70/7079
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A mechanical lock and key, which may have a conventional cylinder with mechanical bittings, includes an electronic access control feature for preventing opening of the lock, even with the proper mechanical key, unless prescribed conditions are met. The lock cylinder, preferably in the cylinder plug, is fitted with a small ID or "serial number" chip which is read when a voltage is applied. A connected device, also very small, is an addressable switch. The switch is connected to a solenoid capable of withdrawing a blocking pin, when the switch is activated and conveys voltage to the solenoid. The mechanical key has a key head with a battery, microprocessor and database. When the key is inserted into the lock, a one-wire bus connection conveys the lock ID to the microprocessor in the key, a comparison is made by the microprocessor to determine whether the lock is authorized to be opened, and if so, a code for the addressable switch, determined from the key database, is sent via the one wire bus to the switch, which causes the switch to conduct power to the solenoid, withdrawing the blocking pin and enabling opening of the lock. A record is made in the database as to each instance of o…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.