Instrumented Printer Platen With Feedback Control
Original Publication Date: 1985-Sep-01
Included in the Prior Art Database: 2005-Feb-19
Instrumenting an H-shaped printer platen with piezoelectric film force and impact sensors permits complex flight time control for providing controlled impacts required for high quality high speed printing. In high speed printing, hammer flight time variation becomes the key technical problem. Hammer flight time must be controlled to vary less than twenty microseconds. Since there are many hammers in the system, their parameters vary from one to the other. Electronic adjustment of hammer flight time is necessary. Hammers are calibrated in manufacture or major service by use of a timing bar, which is an electrical switch placed in the platen position and operated by impact. The platen has to be manually replaced by the timing bar.