Non return to home rack shift selection mechanism for a single element printer

摘要

Disclosed is a mechanism for shifting the rack of a selection mechanism for a single element printer from one position to another in timed relationship to the translation of a barrel cam which provides the necessary mechanical input to control the amount of rotation of the typehead. The control of the rack shift mechanism is a cam arrangement operated in timed relationship with the translating barrel cam to provide for the shifting of the rack at the beginning of each print cycle, if necessary, and the retaining of the rack in its shifted position at the completion of the cycle, thereby eliminating the necessity to provide for the time required to shift the rack back to its home position at the end of the cycle. The elimination of the restore operation of the rack provides more time during the cycle to operate the selection mechanism and accomplish printing or conversely provides for a smaller amount of time being required for the necessary functions thereby providing the capability of operating the remainder of the mechanism at a faster rate.