Abstract
The pin position of print hammer is an important design factor, affecting both impact force and the hammer vibration after collision. The former is a main factor determining the density of printed dots, and the latter plays an important role in determining the returning time of hammer to the home position. In this paper, impact force and the energy of each vibrating mode are calculated for two typical hammer structures varying the pin position over several parameters. It is found that the print hammer normally acts as a two-degree-of-freedom vibrating system, and the pin position has an optimal range where the impact force is appropriate for clear printing, and higher order modes of vibration are effectively suppressed.
