Methods and apparatus to control a heater associated with a printing nozzle are disclosed. A method comprising controlling a heater associated with a printing nozzle to reduce a heat output of the heater based on a determination that the printing nozzle is outside a print area and printing an image on a substrate using other printing nozzles while the heat output of the heater is reduced.

An ejection surface extends in a first direction as a scanning direction and a second direction orthogonal to the first direction and is externally exposed. A plurality of nozzles opens at the ejection surface. A plurality of partial channels is located inside the ejection surface, and at bottom surfaces on a side of the ejection surface, the nozzles open. The plurality of nozzles is arranged in a direction intersecting with the first direction in plural rows to constitute a plurality of nozzle rows. The number of the nozzles arranged in each row is greater than the number of the plural rows. Between the nozzles in each nozzle row, the nozzles in other nozzle rows appear as seen in the first direction. A position of openings in the bottom surfaces of the partial channels differs across at least some of the nozzles in each nozzle row.

In some examples, a method includes, in response to a fluid firing unit being operated according to a normal printing mode, applying a first voltage to the fluid firing unit to fire the fluid firing unit during a printing operation. The method further includes determining, using a sensor, whether a predetermined condition is met, and in response to determining that the predetermined condition is met, operating the fluid firing unit according to a recovery mode in which a second voltage higher than the first voltage is applied to the fluid firing unit to clean the fluid firing unit.

A liquid discharge apparatus uses a drive signal including a micro-vibration waveform which causes the piezoelectric element to micro-vibrate such that an ink is not discharged from the nozzle in a case of being applied to the piezoelectric element as the drive signal and a drive waveform which deforms piezoelectric element such that the ink is discharged from the nozzle in a case of being applied to the piezoelectric element as the drive signal. The presentation unit selectably presents the indirect information from which the ink discharge status can be estimated such as the types of ink and the usage status of the ink or the like. The control unit changes the strength of the micro-vibration caused by the micro-vibration waveform based on the indirect information selected on the presentation unit.

A printing apparatus includes a printhead with a plurality of print elements for generating energy used for printing an image on a print medium, a first temperature detection element and a second temperature detection element at positions different in a direction of a print element array in which the plurality of print elements are arrayed. The apparatus corrects a signal concerning a head temperature based on an output from the first temperature detection element, and corrects, based on the corrected signal concerning the head temperature, a signal concerning a head temperature output from the second temperature detection element.

An image recording apparatus includes a recording head including a plurality of nozzles from which ink is ejected, a memory, and one or more hardware processors coupled to the recording head and the memory. The one or more hardware processors are configured to: determine, for each of the plurality of nozzles, whether a position of the corresponding nozzle is a position to eject ink; determine whether a successive ejection operation is necessary for a nozzle out of the plurality of nozzles, whose position is determined as the position to eject ink; and cause ink to be successively ejected at the position to eject ink at a predetermined successive ejection frequency from the nozzle that is determined to have the necessity of the successive ejection operation.

In one example in accordance with the present disclosure, a fluid ejection system is described. The fluid ejection system includes a frame to retain a number of fluid ejection devices. Each fluid ejection device includes a reservoir disposed on a first side of the frame and a fluid ejection die disposed on an opposite side of the frame. Each fluid ejection die includes 1) a fluid feed slot formed in a substrate to receive fluid from the reservoir, 2) an array of nozzles formed in the substrate to eject fluid, and 3) an ejection adjustment system to selectively adjust an amount of fluid ejected from the fluid ejection devices.

In a case of executing first printing that printing is performed by using a first group, which includes nozzles of a nozzle array whose distances to a detection unit are less than a first predetermined value, and thereafter executing second printing that printing is performed by using a second group, which includes nozzles of the nozzle array whose distances to the detection unit are equal to or less than the first predetermined value and are equal to or more than a second predetermined value, a first driving pulse for the first printing is determined by using a first temperature, which is detected by the detection unit when the first printing is performed. A second driving pulse for the second printing is determined by use of a second temperature, which is derived based on the first temperature and corresponds to a temperature of the nozzles of the second group.

There are provided a characteristic table generation system and so on capable of enhancing the convenience of the user. The characteristic table generation system according to an embodiment of the present disclosure is a system for generating a predictive voltage characteristic table for defining a predictive characteristic curve, the system including a data acquisition section configured to obtain a measured viscosity characteristic table defining a measured characteristic curve between viscosity and temperature of the liquid, and a predetermined parameter separately, as input data, a conversion coefficient generation section configured to generate a conversion coefficient used when performing a conversion process from the measured characteristic curve into the predictive characteristic curve based on the predetermined parameter using a first analytical method as a predetermined analytical method which takes the predetermined parameter as an explanatory variable, and which takes the conversion coefficient as an objective variable, and a table generation section configured to perform the conversion process using the measured viscosity characteristic table and the conversion coefficient generated by the conversion coefficient generation section to thereby generate the predictive voltage characteristic table.

A printing apparatus includes a print head provided with a discharge port that discharges liquid and a pressure chamber filled with the liquid to be discharged from the discharge port, and configured to perform a printing operation by discharging the liquid from the discharge port based on print data, includes a circulation unit that performs circulation of the liquid in a circulation passage including the pressure chamber in a state where the printing operation is performed, and includes a control unit that controls the circulation unit to continue the circulation for a predetermined time after the printing operation is completed.