A liquid discharge device includes a first discharge portion, a second discharge portion, a first drive circuit outputs a first drive signal that the first discharge portion discharges a liquid having a first discharge amount, a second drive circuit outputs a second drive signal that the first discharge portion does not discharge a liquid, a third drive circuit outputs a third drive signal that the second discharge portion discharges a liquid having a second discharge amount, and a fourth drive circuit outputs a fourth drive signal that the second discharge portion does not discharge the liquid, in which the third drive circuit is located between the first drive circuit and the second drive circuit along the one direction, and a shortest distance between the fourth drive circuit and the second drive circuit is shorter than a shortest distance between the fourth drive circuit and the third drive circuit.

A liquid discharge device including a substrate that includes a first through-hole, a first drive circuit, a second drive circuit, a third drive circuit, a metal frame, and a first screw that is inserted through the first through-hole and attaches the metal frame to the substrate, in which the first drive circuit outputs a first drive signal, the second drive circuit outputs a second drive signal, the third drive circuit outputs a third drive signal, the first drive circuit, the second drive circuit, and the third drive circuit are located side by side in an order of the first drive circuit, the second drive circuit, and the third drive circuit on the substrate along one direction, and the first through-hole is located between the first drive circuit and the second drive circuit in the one direction.

A liquid droplet discharging apparatus includes: a discharging head having: a liquid channel including a nozzle; and an energy applying part which applies, to liquid inside the liquid channel, discharge energy for discharging a liquid droplet from the nozzle; a signal outputting circuit which outputs signals depending on whether the nozzle satisfies a predetermined discharging performance; and a controller. The controller determines whether the nozzle satisfies the predetermined discharging performance, and estimates viscosity of the liquid inside the discharging head based on: viscosity estimation data in which discharge energy information and viscosity information are associated with each other, and a result of the determination performed in a case that the controller controls the energy applying part based on the discharge energy information and that the discharge energy is thereby applied to the liquid inside the liquid channel.

A liquid discharge method of discharging a liquid from a nozzle of a liquid discharge head by applying a drive pulse to a drive element of the liquid discharge head includes an acquisition step of acquiring a recording condition, and a driving step of applying the drive pulse to the drive element. The drive pulse includes a first potential, a second potential different from the first potential, and a third potential different from the first potential and the second potential. The second potential is to be applied after the first potential, and the third potential is to be applied after the second potential. In the liquid discharge method, in the driving step, the drive pulse having the first potential that varies depending on the recording condition acquired in the acquisition step is applied to the drive element.

According to one embodiment, a liquid ejection head includes a pressure chamber that contains a liquid, an actuator to change the pressure in the pressure chamber according to an applied drive signal, and a drive circuit to apply a first drive signal to the actuator when a single droplet is to be ejected from the pressure chamber and a second drive signal to the actuator when two or more droplets are to be ejected in series from the pressure chamber. The first drive signal has a first auxiliary pulse before a first ejection pulse. The second drive signal has a second auxiliary pulse before the first ejection pulse. A pulse width of the first auxiliary pulse is greater than a pulse width of the second auxiliary pulse.

An ejection device includes: an ejection unit provided with an ejection port configured to eject an ejection material; a piezoelectric element configured to cause the ejection material to be ejected from the ejection unit; a first liquid chamber connected to the ejection unit and configured to supply the ejection unit with the ejection material; a pressure control unit configured to control a pressure in the ejection unit by controlling a pressure in the first liquid chamber; and a detection unit configured to detect a wetness of an ejection port side surface.

A liquid ejecting apparatus including a liquid ejecting portion that ejects a liquid in a pressure chamber from a nozzle that communicates with the pressure chamber, a liquid supply flow path that supplies the liquid stored in a liquid storing portion to the liquid ejecting portion, a degas module provided in the liquid supply flow path, a vacuum degree adjustment mechanism configured to adjust a vacuum degree of the degas module, a state detecting mechanism configured to detect a state inside the pressure chamber, and a control portion that drives and controls the vacuum degree adjustment mechanism based on a detecting result of the state detecting mechanism.

A head unit includes a plurality of ejection portions that include a first ejection portion and a second ejection portion, a determination portion that determines a liquid ejection state of the first ejection portion and determines a liquid ejection state of the second ejection portion, and a storage portion that includes a first storage region storing first determination information indicating a determination result for the first ejection portion from the determination portion, and a second storage region storing second determination information indicating a determination result for the second ejection portion from the determination portion.

A head unit control device that controls a head unit including a plurality of ejection portions that includes a first ejection portion and a second ejection portion and a determination portion that determines a liquid ejection state of the first and second ejection portion, and includes a reception portion that receives, as one data set, determination result information including first determination information indicating a determination result of the liquid ejection state of the first ejection portion from the determination portion and second determination information indicating a determination result of the liquid ejection state of the second ejection portion from the determination portion, and ejection portion information including information indicating the number of the plurality of ejection portions included in the head unit, from the head unit, and an ejection control portion that controls the plurality of ejection portions based on the one data set received by the reception portion.

A print head includes: an integrated circuit apparatus that switches whether or not to supply drive signals to a plurality of piezoelectric elements, and includes a first circuit block that switches whether or not to supply the drive signal, a second circuit block that switches whether or not to supply the drive signal, a third circuit block that switches whether or not to supply the drive signal, a fourth circuit block, and a first buffer area, a second buffer area, and a third buffer area in which no circuit element is located, in which the first buffer area is located between the first circuit block and the fourth circuit block, the second buffer area is located between the second circuit block and the fourth circuit block, and the third buffer area is located between the third circuit block and the fourth circuit block.