Coded key-type locking system

Claim 1

A locking system comprising: a key having a conductive carrier, an insulating base on said carrier; at least one first conductive strip, on said insulating base, means for connecting said first conductive strip to said carrier; at least one further second conductive strip on said insulating base; an insulating layer covering said first conductive strip and said second conductive strip, said insulating layer formed with a plurality of windows which are each traversed by said first conducting strip and said second conducting strip, and a coating layer which selectively insulates each window by either insulating the first conductive strip in a first information mode or the second conductive strip in a second information mode or the entire window in a third information mode so as to code each of said windows with an information code formed from a group of at least three of said information modes; a reader cooperating with said key and provided with: a reading set of first contacts coming into electrical contact with said strips through said windows during insertion of said key into said reader for detecting the selective insulation of the strips of said windows, a coding set of second contacts arranged in an arbitrary manner and quantity at least some of which are electrically connected to a potential supply, said second contacts being electrically connected to uninsulated strips of selected ones of said windows in accordance with said information code during insertion of said key in said reader, and a potential supply contact connected to said supply and engageable with said carrier for applying an electrical potential to said carrier and to said first conductive strip enabling said reading set of first contacts to read said contained information code from said key in the form of electrical potentials detected by said reading set of first contacts; and electronic means operatively connected to said reader and responsive to the electrical potentials detected by said reading set of first contacts for operating a lock depending upon correctness of the code represented by the arbitrary arrangement of said coding set of second contacts and the information code of the key.