Variable platen pressure control for a thermal transfer printer

A multi-color thermal transfer printer having a plurality of printing stations, said printer comprising:

• a thermal transfer printing head at each of said printing stations;
• a printing ribbon having an ink of a pre-selected color at each of said printing stations;
• a pivotally-mounted roller platen assembly at each of said stations for pressing a respective one of said printing ribbons and a web of material to be primed upon, against a respective one of said printing heads at a variably selectable pressure to transfer said ink from said respective one of said ribbons to the web of material;
• and
• a cylinder device at each of said stations, said cylinder device adjustably pressurized by a fluid medium and engaged with a respective one of said roller platen assemblies for applying said variably selectable pressure to said respective one of said pivotally-mounted roller platen assemblies.

A multi-color thermal transfer printer for printing multi-color license plate images on a web of retroflective sheeting material, said printer having a plurality of printing stations, said printer comprising:

• a thermal transfer printing head at each of said printing stations;
• a printing ribbon having an ink of a pre-selected color at each of said printing stations;
• a pivotally-mounted roller platen assembly at each of said stations for pressing a respective one of said printing ribbons and a web of material to be printed upon, against a respective one of said printing heads at a variably selectable pressure to transfer said ink from said respective one of said ribbons to the web of material;
• and
• a cylinder device at each of said stations, said cylinder device adjustably pressurized by a fluid medium and engaged with a respective one of said roller platen assemblies for applying said variably selectable pressure to said respective one of said pivotally-mounted roller platen assemblies.