US Patent 7568696 Item printing system

An item printing system for printing imprints on moving items, comprising: an item transport path through which items are in use transported in a transport direction; an item transport unit for transporting items through the item transport path; a printing unit (11) for printing imprints on items transported through the item transport path; a free roller (27) driven by respective items transported through the item transport path; and a speed measurement unit for measuring speed of rotation of the free roller, wherein the measured speed of rotation of the free roller is utilised to provide relative control of printing by the printing unit and speed of transport of items by the item transport unit.