Driving ink jet recording elements

Claim 1

In a method for driving an ink jet recording element of the kind comprising a compression chamber for containing the ink, and in which the volume of the compression chamber is altered by means of a piezo-electric transducer to which a control voltage can be applied and wherein the compression chamber will expand if a control voltage is applied in the direction of the polarisation voltage of the transducer and will contract if a control voltage is applied in the opposite direction, the method comprising the steps of (a) during a preparation phase, in a first defined time interval, applying to the piezo-electric transducer a control voltage in the polarisation direction to expand the compression chamber past its static condition, (b) during a write phase in a second defined time interval immediately following the first time interval, applying to the piezo-electric transducer a control voltage in said opposite direction to constrict the compression chamber past said static condition, and (c) during a subsequent regeneration stage in a third defined time interval immediately following said second time interval, applying to said transducer a control voltage in said polarising direction to again expand the compression chamber past its static condition, the currents of said voltages forcing said expansion and constriction during said phases and time intervals.