There is provided a liquid discharge apparatus including: a liquid discharge head; a relative movement mechanism performing relative movement between the liquid discharge head and a medium; a velocity signal output circuit; and a controller performing a constant velocity discharge operation and an acceleration/deceleration discharge operation. In the constant velocity discharge operation, the controller determines a discharge timing based on information about a representative value of relative velocity obtained based on a plurality of pieces of preceding velocity information. Further, in the acceleration/deceleration discharge operation, the controller obtains approximate information in which a change in the relative velocity is approximated based on distribution of the relative velocity, and the controller determines a discharge timing based on the approximate information.

A controller is configured to determine which of a first position and a second position is located at a farther downstream side in a moving direction of an ejector and to set a determined position as a turn position. The first position is a first distance away from an image formation end position in the moving direction. The second position is a second distance away from an image formation start position in the moving direction. The image formation end position is an end position of image formation onto a sheet in a conveyance process of the ejector before turning at the turn position. The image formation start position is a start position of image formation onto the sheet in a conveyance process of the ejector after turning at the turn position. The second distance is longer than the first distance.

An image recording apparatus includes a carriage which reciprocatingly moves in a scanning direction, a head mounted on the carriage to jet liquid, a speed sensor which acquires speed data related to speed of the carriage, and a controller configured to: record an image by executing a recording pass in which the liquid is jetted from the head toward a recording medium while moving the carriage once toward one side in the scanning direction; determine whether the speed indicated by the speed data is lower than a threshold value during the recording pass; and based on determination that the speed indicated by the speed data is lower than the threshold value at a first point of time in the recording pass, determine whether to suspend or continue the recording pass by referring to the speed data acquired after a predetermined time since the first point of time.

Provided are a position detection device, a printing apparatus equipped with the position detection device and a position detection method which make it possible to set an original point on a deviation-free appropriate position with no need of highly accurate adjustment of built-in positions of a linear encoder and an original point sensor.

In a case where a point that low-to-high switching of an output from a scale sensor is detected is set as a light transmission timing, a point that high-to-low switching of the output is detected is set as a light shielding timing and an output change point that an original point sensor detects is set as a detection timing, in a duration time D1 which lasts from the detection timing to a first light transmission timing which is the closest to the detection timing and a duration time D2 which lasts from the detection timing to a first light shielding timing which is the closest to the detection timing, when the duration time D1>the duration time D2, a position of a moving body which is obtained at a second light transmission timing is set as an original point and when the duration time D1<the duration time D2, the position of the moving body which is obtained at a second light shielding timing (the first light shielding timing) is set as the original point.

A droplet ejection apparatus comprising: a droplet deposition head comprising an array of actuating elements and a corresponding array of nozzles; actuating circuitry, configured to apply drive waveforms to said actuating elements, thereby causing the ejection of fluid in the form of droplets through said array of nozzles onto deposition media, which are moved relative to the head; and head controller circuitry, configured to: receive an input set of ejection data; generate a series of sub-sets of ejection data based on the input set; and send said series of sub-sets of ejection data to said actuating circuitry; wherein the actuating circuitry is further configured so as to, for each sub-set of ejection data, apply drive waveforms to said actuating elements such that they repeatedly eject droplets from one or more nozzles, thus depositing successive rows of droplets, the one or more nozzles and the sizes of the droplets ejected therefrom being determined by the current sub-set of ejection data, each of the one or more nozzles ejecting droplets with a substantially constant frequency of 1/T; wherein the apparatus is configured to receive deposition media speed data, which indicates the current speed of relative movement of the head with respect to the deposition media; and wherein the apparatus is configured such that the head switches from ejecting droplets in accordance with a current subset of ejection data to ejecting droplets in accordance with a consecutive sub-set of ejection data in the series at a time determined in accordance with said media speed data, with the time interval between starting ejecting droplets in accordance with successive sub-sets of ejection data varying inversely with the current speed of relative movement of the head.

A print device includes a first head, a second head, a platen, a guide member, a receiving portion, a processor, and a memory that stores computer-readable instructions that cause the print device to perform processes including: test printing that involves printing a test pattern by ejecting the second ink at a first timing and a second timing at a first sub-scanning direction position, and further, ejecting the second ink at a third timing and a fourth timing at a second sub-scanning direction position; and determining that involves, when one of the first and the second timing is received, determining the received timing to be the ejection timing of the second ink at the first sub-scanning direction position, and, when one of the third and the fourth timing is received, determining the received timing to be the ejection timing of the second ink at the second sub-scanning direction position.

A controller is configured to determine which of a first position and a second position is located at a farther downstream side in a moving direction of an ejector and to set a determined position as a turn position. The first position is a first distance away from an image formation end position in the moving direction. The second position is a second distance away from an image formation start position in the moving direction. The image formation end position is an end position of image formation onto a sheet in a conveyance process of the ejector before turning at the turn position. The image formation start position is a start position of image formation onto the sheet in a conveyance process of the ejector after turning at the turn position. The second distance is longer than the first distance.

An ink-jet printing device according to the present invention includes: first and second nozzles each configured to discharge ink droplets onto a recording medium being conveyed; a calculation unit to calculate a landing position difference on the recording medium being conveyed at a conveyance speed based on first and second conveyance speeds and first and second landing position differences; and a timing control unit to control each of timings of ink droplet discharge from the first and second nozzles based on the landing position difference calculated by the calculation unit. This configuration allows appropriate correction of variance in the landing positions of ink droplets discharged from the nozzles.

An ink-jet recording apparatus, including: a recording head including a first nozzle communicating with a first chamber storing a first ink and a second nozzle communicating with a second chamber storing a second ink whose viscosity change rate differs from the first ink; and a controller configured to determine a drive voltage to be a first voltage and determine voltage application timings for the respective first and second nozzles to be a first timing when estimated viscosity of the first ink is lower than a first viscosity and to determine the drive voltage to be a second voltage higher than the first voltage, determine the voltage application timing for the first nozzle to be the first timing, and determine the voltage application timing for the second nozzle to be a second timing different from the first timing when the estimated viscosity is equal to or higher than the first viscosity.

The invention relates to a method for actuating an inkjet print head, comprising at least one printing system having a nozzle on the side of an ink chamber which faces a substrate to be imprinted, and which is delimited at least in areas, preferably in its area facing away from the print substrate, by a diaphragm that is movable away from the ink chamber by electrically actuating a piezo element that is mechanically coupled to the diaphragm, so that ink is drawn into the ink chamber from a reservoir, and the diaphragm is movable into the ink chamber so that an ink drop is ejected from the ink chamber through the nozzle, wherein the printing system made up of the ink chamber, diaphragm, piezo element, and the electronic control system thereof represents an oscillatable structure which, when actuated at high energy, is excited to oscillate at a natural frequency f.sub.res that exhibits resonance; i.e. the oscillation with the period T.sub.res=1/f.sub.res undergoes little or no attenuation, and wherein the brightness of a pixel to be printed is varied in that, for each pixel, a sequence of multiple ink drops is ejectable in succession from the same nozzle at a time interval of T.sub.drop=1/f.sub.drop, and energy is only introduced into the printing system via the actuation signal precisely when an ink drop is actually to be ejected.