Abstract: A driving method for an ink jet printing head includes a vibration application step and an ink refresh operation step. In the vibration application step, small vibrations, which do not cause ink drop discharge from nozzles of the ink jet printing head, are applied to pressure-generation chambers of the ink jet printing head corresponding to nozzles which are not executing ink drop discharge. In the ink refresh operation step, ink refresh operation, for removing the ink in the nozzles and replacing the ink with fresh ink, is periodically executed according to a refresh operation cycle which is appropriately set based on the temperature and/or humidity measured around the ink jet printing head. The ink refresh operation is executed by means of forcible ink drop discharge from the nozzles, ink suction by a pump, etc. For example, the refresh operation cycle is set shorter as the temperature around the ink jet printing head gets lower and as the humidity around the ink jet printing head gets lower.

Abstract: An ink cartridge for supplying ink to a recording head is detachably mounted on a cartridge holder. A calculator performs calculation of an ink amount consumed by the recording head. A counter updates a residual ink amount in the mounted ink cartridge based on the consumed ink amount calculated by the calculator. A monitor monitors an ink amount contained in the mounted ink cartridge to judge at least an ink-end state in which the ink amount in the ink cartridge is a predetermined amount or less. A corrector corrects the way of calculation in the calculator based on the residual ink amount indicated by the counter, when the monitor judges that the mounted ink cartridge is in the ink-end state.

Abstract: Document characteristics such as print media and selectable print quality variations are used to determine printhead servicing, e.g., service spitting of ink-jet nozzles. If the next sweep contains the next color in the pen or printhead set, and the next sweep would be greater than the number of sweeps since the last firing of that color ink—whether on page or at the service station—and the last sweep did not fire droplets of the color, a decap service spit and nozzle firing tracking reset is triggered. All service calls spit fire all nozzles, so all timer values are reset whenever at a service spit. Reaching or exceeding a fail-safe limit similarly triggers a decap service spit or other known manner service station operations.

Abstract: An ink jet printer is adapted to drive a piezoelectric element by applying pulse voltage having waveforms of A1-A8 based on image data, fly ink drops respectively having sizes corresponding to waveforms A1-A8 of the pulse voltage, and record an image on a recording sheet. In the ink jet printer, a rise rate of pulse voltage having waveforms A1-A3 corresponding to ink drops of relatively small sizes is set such that the rise rate is high compared with that of pulse voltage having waveforms A4-A8.