| 摘要 |
PURPOSE:To prevent the positional shift of a printing head generated when said head passes the crossing part of both grooves of a lead screw, by making the groove of the forward path of said screw deeper than that of the backward path thereof. CONSTITUTION:A screw roller 13, to which pressing force is applied by a spring 15, is engaged with the deep groove 16a of a lead screw in the forward path of a carriage and engaged with the shallow groove 16b thereof in the backward path of said carriage. Therefore, the positional shift of a printing head, which is generated when said head passes the crossing part of the grooves 16a, 16b, is prevented in the forward path performing printing and printing accuracy is enhanced. |
