Abstract: A sheet media feed mechanism including a sheet media tray, the sheet media tray having a lower tray for holding a stack of automatic-feed cut sheet media and an upper tray for holding individual sheets of manual-feed sheet media. The lower tray has a pair of corner-pick separators for separating the top sheet of sheet media from the stack. The upper tray has a frame positioned over a rear portion of the lower tray leaving a front portion of the lower tray exposed, and pair of flexible sidekicks extending out over the exposed portion and having a sheet media separator at the front tips of the sidekicks. A pair of D-rollers mounted on a shaft pick the top sheet of sheet media from the lower tray when no sheet media is present at the upper tray, the D-rollers also adapted to pick the top sheet of sheet media from the upper tray when at least one sheet of sheet media is present thereat. The picked sheet media is then fed to a feed path.
Abstract: A printing head for forming dot matrix characters which includes a wire stylus assembly having a plurality of guide bearings spaced to reduce the wear of the tip bearing, and to minimize buckling and resonances. Each stylus is driven by an electromagnetic actuator having a hinged armature, with the stylus drive point at the center of percussion of the armature with respect to the hinge line. Damping is effected at the same point. The armatures are shaped to drive the styli directly in line with the stylus wires without introducing a moment. Individual adjustments for magnetic gap are provided. A retainer device for holding all of the armatures in place during assembly is also provided.
Abstract: A timing and control circuit for a wide spanning impact hammer used in a digital printer can be fabricated by using a phase lock loop oscillator driven by a character pulse clock to output a plurality of timing pulses during the character pulse width. Appropriate intervals are selected from the timing pulses to generate a plurality of shifted timing pulses to be used as inputs to logic circuitry. Combination of the shifted timing pulses and logic circuitry together with control commands from a printer controller, can be used to generate a hammer trigger and hammer reset pulse. The hammer trigger and reset pulses are used in a conventional hammer matrix to fire the multiple spanning hammers at the appropriate times.