PURPOSE: To enable a high speed printing doubling the speed in the past while reducing the cost of the printing system to one-half in terms of the same speed specification by allowing the reverse direction movement of a paper feeding mechanism with respect to a dot head.

CONSTITUTION: As rocking motor 16 rotates, a paper feeding mechanism 2, namely, a paper head 3 moves in the opposite direction with respect to dot head carrying section 1 through rock cams 13 and 15, which doubles the relative movement speed of the dot head 9 with respect to the printing paper 3. The relative amplitude of the dot head 9 also doubles with respect to the paper 3 thereby permitting the doubling of the list pitch in the rocking direction B of a pin on the dot head 9. This makes the number of required pins and the cost of the printing system to one half in term of the same printing speed. In addition, when the dot head 9 by B way is reduced to half in the size and mounted in the paper feeding direction A, the printing speed can be doubled with the dot heads 9 the same in the number as in the past.