Programmable key and lock

Claim 2

In an electronic lock and key system suitable for use with data entry and display terminals and the like, the lock comprising: an addressable memory medium having preselected locations therein containing arbitrary coded patterns; a receptacle adapted to retain an insertable key type device having coded indicia thereon; means for scanning the retained key type device and deriving therefrom a memory address and an arbitrary coded pattern; means responsive to the deriVed memory address for extracting the contents from that location in the memory medium specified by the memory address; comparison means for providing signal indication of the match or mismatch condition between the extracted memory contents and the arbitrary coded pattern; and means responsive to a mismatch signal from the comparison means for maintaining the lock inoperative.

Claim 3

In an electronic lock and key system according to claim 1, wherein; the key type device comprises a titanium oxide filled polyvinyl chloride card and having coded indicia on the card surface formed from a pigment reflective in the visible light region and absorbent in a selected non-visible light region.

Claim 4

In an electronic lock and key system according to claim 2, wherein: the pigment reflects white light in the visible light region and absorbs infrared light in the non-visible light region.

Claim 5

In an electronic lock and key system according to claim 1, wherein: the indicia on the key type device is encoded in delta distance code, said delta code being formed from distance variations between successive markings or the like upon the code bearing surface.

Claim 6

In an electronic lock and key system according to claim 1, wherein the receptacle comprises: means for insertably retaining the key type device; means for scanning the key type device with light in the non-visible region; and means for converting reflected light variations into corresponding electrical variations.

Claim 7

In an electronic lock and key system according to claim 1, wherein the addressable memory medium includes: a disc partitioned into sectors in which each sector constitutes a distinct memory location, the disc having an arbitrary pattern encoded at each address; the extracting means comprise: means for optically scanning the disc arbitrary patterns; means for positioning the disc memory location designated by the derived memory address.

Claim 8

In an electronic lock and key according to claim 1, wherein the comparison means comprise: a first and second register, means for converting the scanned key type coded indicia and the memory contents into corresponding digital representations; means for loading the digital representation into the respective first and second register; and means for generating a first signal if the register contents match and a second signal if said contents mismatch.

Claim 9

In an electronic lock and key system suitable for use with data entry and display terminals; the lock comprising an addressable memory medium having preselected locations therein containing arbitrary digitally coded patterns; a receptacle adapted to retain an insertable card having indicia thereon coded in delta distance code; means for scanning the retained card and deriving a memory address and an arbitrary pattern in delta distance code; means for converting the scanned delta distance code memory address into a digital memory address; means responsive to the derived and converted digital memory address from the card for extracting the contents from the memory medium; said means coacting with the converting means for converting the memory address contents into a digital equivalent; comparison means for providing signal indication between the match and mismatch condition between the card derived digitalized arbitrary pattern and the digitalized contents of the memory address; and means responsive to a mismatch signal for maintaining the lock inoperative.

Claim 10

In an electronic lock and key system suitable for use with data entry and display terminals; the lock comprising an addressable memory medium having preselected locations therein containing arbitrary digitally coded patterns; a receptacle adapted to retain an insertable card having indicia thereon coded in delta distance code; means for scanning the retained card and deriving a memory address and an arbitrary pattern in delta distance code; means for converting the scanned delta distance code memory address into a digital memory address; means responsive to the derived and converted digital memory address from the card for extracting the contents from the memory medium; said means coacting with the converting means for converting the memory address contents into a digital equivalent; comparison means for providing signal indication between the match and mismatch condition between the card derived digitalized arbitrary pattern and the digitalized contents of the memory address; and means responsive to a mismatch signal for maintaining the lock inoperative.

Claim 11

In an electronic lock and key system according to claim 8, wherein the converting means comprise: means responsive to successive abrupt signal changes from the delta distance code source defining successive time intervals T for generating a first binary value if Tn Tn 1, and for generating a second binary value if Tn not = Tn 1.

Claim 12

In an electronic key and lock system according to claim 9, wherein the converter comprises: a source of signals of frequency F and mF, where m lies in the range 1 < or = m < <2; first counting means A and B drivable at a rate of F hertz; second counting means A'' and B'' drivable at a rate of mF hertz; means for alternately coupling the first and second counting means to the signal source in response to successive delta distance coded signal variations defining successive time intervals; and means for generating a first binary value if A(F1)<B''(mF2) and A''(mF2)>B(F1) and for generating a second binary value if either A(F1)>B''(mF2) or A''(mF2) >B(F1) where F1 and F2 are frequencies applied at two distinctive time intervals 1 and 2.