Automatic Printhead Cleaner
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07
A print ribbon malfunction detection system is modified to incorporate an automatic printhead cleaning system. Printing is effected when printing currents are supplied to a print ribbon 13 through a set of electrodes on head 15. The print ribbon 13 is layered so as to include a resistive layer adjacent the head 15, a conductive layer and a thermoplastic pigmented layer which is brought into contact with a writing sheet (not shown) located opposite head 15. Electrode drivers 17 selectively apply print current to various ones of the print electrodes which inject the current into the resistive layer of ribbon 13. The current injection produces localized heating, causing discrete portions of the ribbon's thermoplastic layer to melt and thus bond to the writing sheet to form a print mark on the sheet.