Abstract: A compact data printer has a printing assembly cantilevered from a pedestal containing the power and control electronics. A tractor feed within the printing assembly draws the print medium (e.g. fan-folded paper) vertically from a supply stack and discharges it, after printing, at a location very near its entrance location to provide a compact print assembly. A print carriage containing a printing band, an anvil, a drive motor, and a ribbon cassette is quickly demountable by an operator from the main frame on which it rests to thereby facilitate maintenance or repair. A compact ribbon cassette minimizes storage volume when stored and protects the user against ribbon smudge during mounting on the print carriage.

Abstract: A type train assembly includes a pair of parallel belts stretched around drive wheels, a series of type carriers centered between and attached to both belts to balance and divide the traction and tension forces, and a guide bar slidably engaging a groove in the rear surface of each type carrier to guide them accurately and to support them firmly for impact by print hammers. The type carriers abut one another in the direction of travel and this combines with the tension in the belts to reduce dragging of the type, which would otherwise result from stretching of the belts occasioned by hammer impact. The carriers are formed with pairs of transverse arms having flanges and projections for gripping the pair of belts, and with recesses for engaging teeth formed in the belts, to fix the carriers firmly thereon.