A liquid droplet discharge apparatus includes a discharge head having a nozzle for discharging liquid droplets onto a printing medium and an actuator for applying pressure to liquid in a pressure chamber communicated with the nozzle; a waveform generating circuit for generating driving waveforms of signals for driving the actuator; a surface information acquiring device configured to acquire information about a surface of the printing medium; and a controller. The controller calculates a volume of a recess on the printing medium based on the information acquired by the surface information acquiring device; causes the waveform generating circuit to generate a driving waveform for filling up the recess in accordance with the volume of the recess; and drives the actuator in accordance with the driving waveform generated by the waveform generating circuit such that the liquid droplets are discharged from the nozzle to the recess.

A liquid discharge device including a first piezoelectric element that has a first electrode and a second electrode and discharges a liquid from a first nozzle by being driven, a second piezoelectric element that has a third electrode and a fourth electrode and discharges a liquid from a second nozzle by being driven, a reference voltage signal propagation path that electrically couples the second electrode and the fourth electrode and propagates the reference voltage signal supplied to a first coupling point to the second electrode and the fourth electrode, and a first capacitor electrically coupled to the reference voltage signal propagation path at a second coupling point provided in the reference voltage signal propagation path, in which the second coupling point is located between the first coupling point and the second electrode in the reference voltage signal propagation path.

In a liquid discharge apparatus, a head unit includes a plurality of print heads, and a housing that houses the print heads, in which a first print head in the plurality of print heads includes a substrate that includes a first side, a second side, a first surface, and a second surface, a first nozzle plate, a first integrated circuit that is provided on the first surface, that outputs an abnormality signal indicating presence or absence of abnormality of the first print head, a first flexible wiring substrate that is electrically coupled to the substrate, and a second integrated circuit that is provided on the first flexible wiring substrate, the second integrated circuit is located between the first nozzle plate and the substrate, and the substrate is provided so that the first surface faces downward and the second surface faces upward in a direction along a vertical direction.

In the print data for a nozzle of a printer, white dots are replaced by pre-ejection pulses. One or more repetitions of the pre-ejection pulses may be inserted into the print data, depending on the actual print speed of the printer, to determine print speed-dependent print data with which the nozzle is activated to print a print image with high print quality.

A liquid discharge apparatus includes a channel member defining a nozzle and a pressure chamber in communication with the nozzle; an actuator which applies pressure to liquid in the pressure chamber, and a controller which applies a drive signal to the actuator. The drive signal includes a rectangular main pulse and a rectangular cancel pulse applied after the main pulse within one discharge period. The actuator is driven by the drive signal in a pull-and-push method to discharge the liquid from the nozzle. If f (kHz) refers to a drive frequency of the drive signal, if Tw (μsec) refers to a time length from a falling edge of the main pulse to a rising edge of the cancel pulse, and if Tc (μsec) refers to a pulse width of the cancel pulse, then the following expression holds: 50≤f≤−11.3×(Tw+Tc)+120.

A liquid discharge device including a first drive circuit, a second drive circuit, a third drive circuit, a fourth drive circuit, a connector coupled to a discharge head, and a substrate that includes a first wiring which couples the connector and the first drive circuit outputting a first drive signal, a second wiring which couples the connector and the second drive circuit outputting a second drive signal, a third wiring which couples the connector and the third drive circuit outputting a third drive signal, and a fourth wiring which couples the connector and the fourth drive circuit outputting a fourth drive signal, in which the first wiring is shorter than the second wiring, the third wiring, and the fourth wiring, and the fourth wiring is longer than the first wiring, the second wiring, and the third wiring.

A liquid ejecting apparatus is configured to drive a driving element in accordance with a driving signal applied by control of the controller. A driving signal includes a first ejection pulse for ejecting liquid, a second ejection pulse for ejecting liquid, and a non-ejection pulse for not ejecting liquid. The controller selects the first ejection pulse and the second ejection pulse to supply to the driving element, when a first amount of liquid is to be ejected from the nozzle in the unit period. The controller selects the non-ejection pulse and the second ejection pulse to supply to the driving element, when a second amount of liquid that is smaller than the first amount of liquid is to be ejected from the nozzle in the unit period. The second amount of liquid is larger than an amount of liquid ejected by only the second ejection pulse.

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.

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.