Ribbon-position switching device for printer

Claim 1

In a printer having a carriage carrying a printing head mounted thereon and capable of being moved in directions parallel to a platen, a cartridge holder for removably holding a cartridge accommodating a multi-colored ink ribbon on which a plurality of different color zones are arranged in rows in the width direction, said cartridge holder being rockably mounted on the carriage so as to be able to move the multi-colored ink ribbon in the width direction relative to the printing head, and a ribbon-position switching device for driving the cartridge holder to bring a desired color zone on the multi-colored ink ribbon to a position corresponding to an end of the printing head for using the desired color zone, the ribbon-position switching device for a printer comprising: a motor with a control means for driving the cartridge holder, said motor being mounted on said carriage; a step member provided on one of the carriage and the cartridge and having engagement recesses corresponding in number to the number of color zones on the multi-colored ink ribbon in the cartridge, the plurality of engagement recesses being arranged at a predetermined pitch in the width direction of the multi-colored ink ribbon in the cartridge held on the carriage holder; an engaging projection member provided on the other of the carriage and the cartridge and biased to be in engagement with one of the plurality of engagement recesses of the step member, the engaging projection member being released from the engagement against the biasing force by sliding contact of the engaging surface of the one engagement recess with the engaging projection member, said sliding contact being caused by the movement of the cartridge holder, said engaging projection member subsequently being brought into engagement with another engagement recess among the engagement recesses; and a fine adjustment mechanism for finely adjusting the relative positions of the carriage and the cartridge held on the cartridge holder to each other by causing a movement of at least one of the step member and the engaging projection member in the width direction of the multi-colored ink ribbon on the cartridge held on the cartridge holder at a pitch less than the pitch of arrangement of the plurality of engagement recesses of the step member.