A "shear-mode" line print head of the kind comprising a piezoelectric material (101) in which there are formed a plurality of ink chambers (112) served by a common ink supply manifold (not shown) and separated by walls (115), each chamber bearing on its interior surface a respective electrode such that by application of a driving voltage across two adjacent chambers the intervening wall (115) distorts to pressurize ink in one of the chambers, to thereby eject ink from an orifice (110), is disclosed. The following features are described:- (a) the arrangement of the ink ejecting chambers into a plurality of similar groups (indicated by broad curly parentheses) repeated seriatim along the length of the head, (b) the alternation of orificed (110) ink-ejecting and non-orificed passive (dummy) ink chambers within each group, both endmost chambers of each group being passive, (c) the separation of the groups by walls (116) of greater thickness, (d) the inclination of the head (as a whole) with respect to the printing direction (broad arrow) and the staggering of the lines of the orifices (131, 132, 133) of respective groups in such manner that, notwithstanding the extra thickness of the inter-group walls (116), the projections (p) of the separations of the orifices as seen in the direction of printing (107) are equidistant, (e) driving the arrangement in a "time-sharing" mode by: (i) within each group, connecting the passive chamber electrodes in common to a group driver, (ii) between groups, connecting a first orificed chamber of each group to a first common driver, a second orificed chamber of each group to a second common driver, and so on. A number of detailed variations are described. IMAGE
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