DE2660934

1514406 Selective printing INTERNATIONAL BUSINESS MACHINES CORP 14 July 1976 [1 Aug 1975] 29246/76 Heading B6F A wire matrix print head has at least two linear arrays of wires and the disposition of the arrays is changeable so that in one position the corresponding wires in each array are aligned with the printing line and in another position they are not. The arrays thus define a coarse matrix for relatively fast printing in the first position and a finer matrix for slower speed printing in the second. As shown in Fig. 1 an array 11 is fixed to print head carriage 1 and array 9 is vertically displaceable relative to it by a cam 21. Alternatively; see Fig. 4 the two arrays QQ1 and RR1 are fixed relative to each other but are rotatable between positions P, S which provide the fine and coarse matrices respectively.