Method and device for checking the serviceability of the print needles of a needle print head

摘要

In the case of a method for checking the serviceability of the print needles of a needle print head, which needles strike against a printing abutment during printing, the vibration of the same which occurs when a print needle strikes against the printing abutment is detected. A signal corresponding to the vibration is correlated with a drive signal for the relevant print needle so that an error signal is produced in the absence of a vibration signal associated with the drive signal. In order to detect the vibration of the printing abutment, the said printing abutment is connected to an accelerometer whose measurement axis is directed parallel to the movement direction of the print needles.