Abstract: A method of ink jet printing using an ink jet imaging device including a plurality of nozzles arranged for expelling droplets of an ink by actuation of an ink channel includes the steps of: a) providing a bit map of a spit pattern comprising an arrangement of refresh dots to be printed by each of the plurality of nozzles; and d) printing the bitmap of the spit pattern. The spit pattern includes a plurality of clusters of refresh dots, each cluster including at least two sequential refresh dots expelled from a single nozzle. A spit pattern for use in such a method is disclosed.

Abstract: A method is provided for actuating an liquid discharge element in an array of discharge elements of a print head. The liquid is provided to the elements of the array through a channel in the print head. A discharge element is provided with a driving signal from a set of signals comprising a discharging signal, a non-discharging signal, and a null signal. Only the first signal generates a drop of liquid, the second and third do not. An amount of discharging signals supplied to the print head is determined in accordance with a required number of droplets. A ratio of non-discharging signals versus null signals for the elements that do not discharge a drop of liquid increases with increasing amount of discharging signals. The elements receiving an non-discharge signal are selected randomly from the elements not discharging a drop of liquid. This extends the time that the print head may be operated without maintenance.

Abstract: A fixing device for fixing a powder image on a receiving sheet in a fixing nip formed by a fixing roller and a pressure roller which has a lower flexural stiffness than the fixing roller. These rollers are pressed against one another by a stationary cushion filled with compressed air and pressing against the pressure roller in a pressure zone situated opposite the fixing nip.When the pressure roller and the fixing roller are driven, tangentially directed frictional forces are exerted on the pressure roller that causes the pressure roller to deflect against a curved support surface which limits the deflection. The pressure roller deflected in the operative position causes a receiving sheet fed through the fixing nip to be stretched in a direction transversely of the direction of conveyance to eliminate any bubbles or corrugations in the receiving sheet.