Ink jet printer drop speed measurement - by measuring time between pressure generator impulse and drop detection signal

摘要

The method, device, and detectors are for monitoring the speed of drops in an ink spray printer and operate when the print head is at one end of its line movement. The head has compression chambers with an ink holder contg. ink or an interchangeable fluid used for monitoring purposes. Ink or the monitoring fluid drops are fed to the head nozzles by applying short duration pressure increases to the compression chambers. A detector enables the time of ejection of a drop from the head. The time between the impulse signal application to the chamber pressure increase generator and the signal from the detector is determined and compared with given measurement path limits. Correction signals are derived from the degree by which the measured time interval lies outside the comparator limits.