An inkjet printing device includes a stage; an inkjet head disposed above the stage and comprising nozzles through which ink is discharged, the ink including bipolar elements extending in a direction; an ink circulation part which supplies the ink to the inkjet head, and to which the ink remaining after being discharged from the inkjet head is supplied; and at least one sensing part disposed between the inkjet head and the ink circulation part and sensing a number of the bipolar elements that are discharged through the nozzles.

In some examples, a print cartridge includes a monolithic molding, and a printhead die embedded into a molding. The printhead die has a front surface exposed outside the molding to dispense fluid drops through nozzles and an opposing back surface covered by the molding except at a channel in the molding through which fluid is to pass directly to the back surface. The printhead die also has a nozzle health sensor molded into the molding to detect defective nozzles in the printhead die.

A control method of a liquid discharging apparatus includes: a discharge inspection step of inspecting discharge abnormality of a nozzle by a discharge inspection mechanism; a remaining oscillation inspection step of inspecting oscillation of the ink inside a pressure chamber by a oscillation inspection circuit when the discharge abnormality is detected; a first correction step of performing correction which corresponds to the attachment of the resin inside the pressure chamber with respect to the driving pulse when abnormality is detected in oscillation; a re-discharge inspection step of inspecting the discharge abnormality of the nozzle after the first correction step; and a second correction step of performing the correction which corresponds to the attachment of the resin inside the nozzle with respect to the driving pulse when the abnormality is not detected in the oscillation in the oscillation inspection step or when the discharge abnormality is detected in the re-discharge inspection step.

A jetting device includes an ejection unit arranged to eject a droplet of a liquid. The ejection unit includes a nozzle, a liquid duct connected to the nozzle, and an electro-mechanical transducer arranged to create an acoustic pressure wave in the liquid in the duct. The jetting device further includes a filter arranged to filter the liquid being supplied into the duct and a filter status detection system arranged to detect an obstruction status of the filter by measuring a property of the liquid in the duct. The filter status detection system includes a circuit configured for measuring the electric response of the transducer, for recording changes in the electric response that represent pressure fluctuations induced by the acoustic wave in the form of a time-dependent function, and for judging the obstruction status of the filter on the basis of that function.

There is provided a head module in which a first direction is a main scanning direction, including: a first nozzle row including a first nozzle; a second nozzle row including a second nozzle; and a third nozzle row including a third nozzle, in which a distance P1 between the first nozzle row and the second nozzle row in the first direction and a distance P2 between the first nozzle row and the third nozzle row in the first direction are expressed as P1:P2=E1:O1 where a value E1 is a positive even number and a value O1 is a positive odd number satisfying O1>E1.

An integrated circuit for a print component including a number of memory bits. The integrated circuit may include a selection circuit to select at least one memory bit of the number of memory bits and fire actuators of a fire pulse group. The integrated circuit may include a memory voltage regulator to provide a write voltage to the at least one memory bit of the number of memory bits.

A print element substrate comprises print elements generating thermal energy for ejecting liquid; and a temperature detection element circuit including temperature detection elements provided corresponding to each of the print elements, and reading temperature information by selectively energizing one of the temperature detection elements, wherein the temperature detection element circuit includes: a signal processing portion outputting a selection signal having a second voltage amplitude larger than a first voltage amplitude, based on an input signal having the first voltage amplitude; a selection switch provided for each of the plurality of temperature detection elements, selecting the temperature detection element; and a first read switch provided for each of the plurality of temperature detection elements, reading a voltage of a terminal of one of the temperature detection element selected by the selection switch, and wherein the selection switch and the first read switch are driven by using the selection signal.

A system and method for determining the operational status of a nozzle in an inkjet printhead having a piezoelectric actuator configured to cause the ejection of ink through the nozzle, the system comprising: a driving circuit configured to apply a driving signal to the piezoelectric actuator during a first time period; and a sensing circuit configured to measure the current within the piezoelectric actuator as a function of time during a second time period after the first time period; wherein the system is configured to determine the operational status of the nozzle in dependence on the time taken for the measured current to reach a predetermined condition during the second time period, or on the slope of the measured current as a function of time during the second time period.

An element substrate, according to an embodiment of this present invention, capable of detecting the behavior of a liquid at a high sensitivity, comprises: a first electrothermal transducer configured to generate heat to discharge a liquid; at least one temperature detection element arranged near the first electrothermal transducer; and a second electrothermal transducer configured to generate heat in association with a temperature detection operation by the at least one temperature detection element.

A maintenance method for a liquid discharging apparatus including a liquid discharging head. The liquid discharging apparatus executes a printing process including a discharging process in which the liquid discharged from the liquid discharging head lands on the medium, and a maintenance process in which the liquid is discarded from the liquid discharging head. The maintenance method includes: counting a unit period number, which is the number of ended unit periods among a plurality of unit periods obtained by dividing a period required for the printing process in accordance with a first condition; executing the maintenance process when the unit period number reaches a defined number; acquiring viscosity information related to viscosity of the liquid inside the liquid discharging head; and decreasing the unit period number when the viscosity information satisfies a second condition.