US 5,745,044 A · Electronic security system

Abstract

An electronic security system includes an electronic lock mechanism and an electronic key, each of which is provided with a microprocessor controller and a memory storing data including an ID code and encryption key codes. The lock microprocessor may either change ID codes stored in its memory or encrypt a seed number to be used for determining access to the lock. The key can only be used to access the lock either once or for a limited number of successive times, and must thereafter be reprogrammed by a host computer to be loaded with either the proper ID code or the appropriate encryption key code for that lock. The electronic lock operates a solenoid which retracts a bolt-blocking mechanism that prevents the unlocking of the bolt even when a key having the correct mechanical key cuts is inserted into the lock. Power for operating the electronic lock as well as the solenoid is provided by a power supply within the key. In a preferred embodiment the key unit is composed of a handheld computer and key module interface.

Claims15

Dependent claims

An electronic security system, comprising:

a lock, including
a lock memory storing therein an identification number of said lock, an encryption code associated with said lock, and a seed number, and
means for encrypting said stored seed number with said encryption code to generate an encrypted seed number;
key means couplable with said lock for communicating therewith, including
a key memory storing therein a list of lock identification numbers and corresponding encryption codes,
means for receiving said identification number of said lock and said seed number from said lock,
means for encrypting said received seed number with an encryption code retrieved from said key code corresponding to said received identification number to generate an encrypted seed number, and
means for transmitting said encrypted seed number to said lock;
said lock further including
means for comparing said encrypted seed number received from said key means with the encrypted seed number generated in said lock, and
means for enabling said key means to open said lock upon determination by said means for comparing that said encrypted seed numbers match.

8 more elements

Dependencies are inferred from the claim text.

Electronic security system

Life of this patent

Electronic security system

Life of this patent

Abstract

Claims15