Method and apparatus for preventing usage of an unauthorized inking ribbon in a thermal printing process

In a method for operating a thermal transfer printer wherein a thermal print head having a plurality of thermal print elements is operated by power electronics and controlled by a control unit to print an imprint on a medium by thermally transferring ink from an inking ribbon to the medium by energization of selected print elements by said control unit, and wherein said inking ribbon and said medium are movably disposed between said print head and a counter-roller with said inking ribbon being unwound from a supply reel and wound onto a take-up reel, the improvement of steps for preventing usage of an unauthorized inking ribbon comprising:

• producing an authorization marking on said inking ribbon at a beginning of said inking ribbon and embodying a piracy-preventing therefor authorization code in said authorization marking identifying said inking ribbon as manufactured by an authorized manufacturer;
• storing said authorization code in a memory accessible by said control unit;
• reading said authorization marking from said inking ribbon and generating a recognition signal corresponding thereto;
• comparing said recognition signal to said authorization code stored in said memory;
• and
• via said control unit, enabling printing by said print head if said recognition signal and said authorization code match and otherwise preventing any printing by said print head.

An inking ribbon cassette for use in a thermal transfer printer having a print head, said inking ribbon cassette comprising:

• a cassette housing;
• a supply reel and a take-up reel rotatably mounted in said cassette housing;
• a receptacle adapted to receive said print head of said thermal transfer printer;
• an inking ribbon entrained around said supply reel and said take-up reel;
• said cassette housing comprising means for guiding said inking ribbon for unwinding said inking ribbon from said supply reel, through said receptacle over said print head, and for winding said inking ribbon onto said take-up reel;
• said inking ribbon having an authorization marking thereon at a beginning of said inking ribbon, embodying a piracy-preventing therefor authorization code identifying said inking ribbon as an authorized inking ribbon manufactured by an authorized manufacturer;
• and
• said cassette housing having a window therein disposed at a location making said authorization code visible from an exterior of said cassette housing as said inking ribbon is unwound from said supply reel.