Abstract: A modular printer chassis, particularly for large scale printers, includes a lower media module which provides a rigid platen media support surface connected to an upper scanning carriage support module by a plurality of fasteners which are tightened at the time of assembly to thereafter permanently hold the modules, which are accurately positioned with the aid of a gauge at the time of assembly, in place so that the accurate inkjet printhead to media spacing in the print zone is maintained.

Abstract: A control processing method and apparatus for dot matrix printers which are ubjected to relatively high levels of vibration and shock. Vibration and shock are detected and, in the event that a known safe vibration or shock level is exceeded, print line data being fed alternately to the print head from a pair of data print buffers coupled to the output of a logic data input buffer are inhibited while the input buffer temporarily stores the incoming data. Drive pulses applied to the stepper motor used to move the print head carriage are simultaneously stopped. When the detected level falls below a set threshold indicative of a safe operating level, normal operation is resumed with the print data again being fed from the input buffer to the print line buffers which are reactivated along with the carriage stepper motor.

Abstract: In an impact printing apparatus including a carriage which carries a rotary type element, the length of time required for a motor drive system for the carriage stop hunting and stabilize at a desired printing position depends on variables including the distance the carriage was moved, character pitch and the like. The apparatus senses these variables and delays hammering of the type element for printing for a length of time calculated to reduce the displacement of the carriage from the desired printing position caused by hunting to an acceptable value while maximizing the effective printing speed.

Abstract: An improved dry lettering printing machine of the type having a printing station, a rotatable disc or type font having embossed characters on the disc and a means for causing the machine to execute a print cycle which includes providing a color carrying ribbon and image carrying tape at the print station, precisely aligning a selected raised character on the disc for printing, exerting a printing force at the printing station, and reciprocating the tape cartridge to advance the tape and ribbon to print the next character at the printing station. The improvement includes an input keyboard for typing the information which is to appear on the tape interfaced with the printing machine with a programmed microcomputer which stores the input data and, with control signals, sequentially causes the printing machine to print a tape according to the information typed on the keyboard.

Abstract: An electric typewriter having a prevention mechanism for preventing printing errors caused by a depression of a few keys in very rapid succession. The prevention mechanism includes a lock member for locking a clutch, which is interposed between a drive motor and a printing mechanism, in a disengaged condition. The lock member is normally held in a non-operational position for allowing the clutch to be engaged, and is moved in response to a special operation of a sensing member to an operational position for keeping the clutch in a disengaged condition. The sensing member is so disposed as to be moved in a distinct way different from the normal operation mode when a few keys have been depressed in very rapid succession.

Abstract: A coded electric signal generating keyboard for a single element typewriter is disclosed which has a keylever signal storing function and includes an interlock mechanism for permitting only one interposer at a time to be moved out of its normal position. Thus after depression of a particular key another key is prevented from being depressed until the interposer moved to an operative position is restored to the normal position during an initial part of a printing cycle initiated in response to depression of the particular key. It further includes an arresting mechanism operable to arrest another subsequently released interposer to an intermediate stored position during the remaining part of the printing cycle whereby another printing cycle may be initiated at the end of such printing cycle.

Abstract: An electromechanical printer having characters of a type font located on radial spokes of a circular type disc is disclosed. The type disc is normally arrested and connected to be driven about its axis by a unidirectional motor source via a slip clutch. Selection-print activating mechanism responsive to source, e.g. keyboard, generated mechanical outputs serve to select a character stop, in an assembly of character stops, corresponding to characters located on the spokes of the type disc and, incident to selection of a character stop, to release the normally arrested type disc. The type disc is provided with counterstops adapted to engage selected character stops positioned in the path thereof and to move the character stop assembly to a frame supported final positioning stop which arrests the type disc with the selected character opposite a print point.