Electronic security device
AssigneeScovill Inc.
InventorWalter J. Aston
Life of this patent
Estimating the term…
Abstract
An electronic security device includes a memory and a card reader which reads a combination code and calculation data from a key card. An electronic circuit compares the content of the memory with the combination code and enables the lock device if a match is found. If the key card is a new one the circuit calculates a new combination code by applying the calculation data to the memory content and, if this new combination code matches that on the key card the memory is loaded with the new combination code.
Claims11
An electronic security device comprising:
- (a) a key means having at least a key combination code and calculation data;
- (b) lock memory means for storing a stored combination code;
- (c) key reading means for reading from said key means said key combination code and calculation data;
- (d) electronic circuit means, connected to said lock memory means and to said key reading means, for
- (1) comparing the key combination code and the stored combination code,
- (2) producing an output for releasing a security device when said key combination code from said key reading means matches said stored combination code,
- (3) calculating a new combination code based upon said stored combination code and said calculation data,
- (4) comparing the new combination code with the key combination code and
- (5) producing said output when said new combination code matches said key combination code.
A method of operating an electronic security device which includes a key with a combination code and calculation data, and a lock having a memory, a key reader, and an electronic circuit connected to said memory and key reader, said method comprising the steps of:
- storing a combination code in said lock memory;
- reading said key combination code and calculation data into said electronic circuit;
- comparing the key combination code and the stored combination code;
- producing an output for releasing said security device when said key combination code from said key reader matches said stored combination code;
- calculating a new combination code based upon said stored combination code and said calculation data;
- comparing the new combination code with the key combination code;
- and
- producing said output when said new combination code matches said key combination code.
An electronic security device comprising:
- (a) a key means having a plurality of keying level instructions one of which is a combination code and another of which is a "lock-out" keying level instruction data;
- (b) lock memory means for storing a stored combination code;
- (c) key reading means for reading from said key means said key combination code and "lock-out" keying level instruction data,
- (d) electronic circuit means, connected to said lock memory means and to said key reading means, for
- (1) comparing the key combination code and the stored combination code,
- (2) producing an output for releasing a security device when said key combination code from said key reading means matches said stored combination code,
- (3) preventing production of said output upon subsequent receipt of non-"lock-out" keying level instruction data.
Dependencies are inferred from the claim text.