Coded key switching system

Claim 2

In a locking system adapted to be operated by keys having different information coded thereon; said locking system including a key receiving station, reading means for sensing the information coded on a key presented at said key receiving station, decoding means for converting sensed information from such a key into an electrical signal, and access control means responsive to such a signal; the improvement comprising: a key verification circuit operatively connected between said decoding means and said access control means for disabling said access control means when a key having a predetermined code thereon is presented at said key receiving station; said key verification circuit comprising separate circuit means corresponding to the code on every key which is adapted to operate said locking system; and void means for operating any of said circuit means, at any time, independently of the other circuit means, to disable said access control means when a key having a code correspondingly to said circuit means is presented at said key receiving station.

Claim 3

The improvement according to claim 1, and further comprising means for restoring each of said circuit means to its original condition at any time, whereby said key verification circuit will not disable said access control means when a key having a code corresponding to such circuit means is presented at said key receiving station.

Claim 4

The improvement according to claim 1, wherein said key verification circuit comprises a voiding circuit which, when closed, disables said access control means; and wherein each of said separate circuit means comprises normally open switch means; and wherein said void means comprises separate means for selectively closing each of said normally open circuit means.

Claim 5

The improvement according to claim 3, wherein said normally open switch means comprises separate conductors and wherein said void means comprises a conductor adapted to connect said first and second conductors.

Claim 6

The imProvement according to claim 1, wherein said key verification circuit comprises: a substantially planar insulative substrate having opposite surfaces; substantially parallel rows of conductive material on one surface of said substrate and substantially parallel columns of conductive material on the opposite surface of said substrate; the intersections of said rows and said columns of conductive material comprising said circuit means; and means for selectively establishing electrical connection between any one of said rows and any one of said columns at substantially the intersection thereof.

Claim 7

The improvement according to claim 1, wherein said key verification circuit comprises a matrix of rows and columns of conductive material; and wherein said circuit means comprise the intersections of said rows and columns.

Claim 8

The improvement according to claim 6, wherein said rows of conductive material lie on one side of an insulative substrate and said columns of said conductive material lie on the other side of said substrate; and wherein each of said void means comprises; a diode having first and second terminals, at least one hooklike electrode electrically connected to the first diode terminal, and spring means relating the diode and electrode such that when the hooklike electrode is electrically connected to one of said rows or columns of conductive material on one side of said matrix substrate, the diode second terminal is resiliently urged into contact with the intersecting column or row of conducting material on the other side of said substrate.

Claim 9

The improvement according to claim 1, wherein each of said separate circuit means comprises normally closed circuit means; and wherein each of said void means comprises mean for selectively opening each of said normally closed circuit means.

Claim 10

The improvement according to claim 1, wherein each of said key receiving stations comprises means for receiving a card having information magnetically coded thereon; and wherein said means for sensing said information comprises means for sensing magnetically coded information on such cards.

Claim 11

In a locking system adapted to be operated by key cards having different information magnetically coded thereon; said locking system including a card receiving station, reading means for sensing the magnetic information coded on a card presented at said key receiving station, decoding means for converting sensed magnetic information from such a card into an electrical signal, unlocking means responsive to such a signal, and disabling means operatively associated with said unlocking means to selectively disable said locking means; the improvement comprising: a code voiding circuit operatively connected between said decoding means and said unlocking means for actuating said disabling means when a card having a predetermined magnetic code thereon is presented at said key receiving station; said code voiding circuit comprising: a substantially planar insulative substrate having opposite surfaces; substantially parallel rows of conductive material on one surface of sad substrate and substantially parallel columns of conductive material on the opposite surface of said substrate; and further comprising electrode means for selectively establishing connection between one of said rows of conductive material and one of said columns of conductive material at the intersection thereof to complete a circuit through said code voiding circuit and actuate said disabling means to disable said unlocking means.

Claim 12

In a locking system adapted to be operated by key cards having different information magnetically coded thereon; said locking system including a card receiving station, reading means for sensing the magnetic information coded on a card presented at said key receiving station, decoding means for converting sensed magnetic information from such a card into an electrical signal, unlocking means responsive to such a signal, and disabling means operatively associated with said unlocking means to selectively disable said locking means; the improvement comprising: a code voiding circuit operatively connected between said decoding means and said unlocking means for actuating said disabling means when a card having a predetermined magnetic code thereon is presented at said key receiving station; said code voiding circuit comprising: a substantially planar insulative substrate having opposite surfaces; substantially parallel rows of conductive material on one surface of sad substrate and substantially parallel columns of conductive material on the opposite surface of said substrate; and further comprising electrode means for selectively establishing connection between one of said rows of conductive material and one of said columns of conductive material at the intersection thereof to complete a circuit through said code voiding circuit and actuate said disabling means to disable said unlocking means.