A liquid discharging head, having individual flow paths, a first manifold, a second manifold, a third manifold, a connecting flow path, and a bypass, is provided. The first manifold extends in a first direction and is provided commonly to the individual flow paths. The second manifold and the third manifold are located on one side and the other side of the first manifold in a second direction. The second manifold and the third manifold are provided commonly to a part of the individual flow path and another part of the individual flow path, respectively. The connecting flow path partly overlaps the first manifold in a vertical direction and connects one end of the second manifold and one end of the third manifold on one side in a third direction. The bypass extends in the vertical direction and connects the first manifold and the connecting flow path.

An actuator drive circuit for a liquid discharge apparatus includes an output switch and a waveform selector circuit. The output switch includes a first transistor configured to supply a first voltage to an actuator when on and a second transistor configured to supply a second voltage higher than the first voltage to the actuator when on. The waveform selector circuit is configured to select, from a plurality of waveforms stored in a waveform memory, a first waveform that causes the output switch to transition to a first state in which the first transistor is on and the second transistor is off, and a second waveform that causes the output switch to transition to a second state in which the first transistor is off and the second transistor is on.

According to one embodiment, a liquid discharge apparatus includes a nozzle plate configured such that a plurality of nozzles are arranged, a liquid supply unit, an actuator, a driving circuit, and a low impedance circuit. The nozzles arranged in the nozzle plate discharge a liquid. The liquid supply unit communicates with the nozzles. The actuator is provided for each nozzle in the nozzle plate. The actuator includes a piezoelectric element. The driving circuit supplies a driving signal to the piezoelectric element of the actuator and drives the actuator to discharge a liquid from the nozzles. The low impedance circuit is connected to the piezoelectric element of the actuator while stress is applied to the nozzle plate due to external factors.

According to one embodiment, a liquid dispensing apparatus includes a mounting unit configured to hold a liquid discharging apparatus that discharges liquid from nozzles simultaneously by an operation of an actuator. An inspection media placement region is provided on which an inspection medium can be placed to receive the liquid discharged from the liquid discharging apparatus. A controller is configured to control the actuator to vary a volume of the liquid discharged from each nozzle for a nozzle inspection operation. The volume is varied according to a predetermined distance between adjacent nozzles that simultaneously discharge liquid and a predetermined contact angle for a droplet of the liquid when on the inspection medium.

According to one embodiment, an actuator of a liquid ejection head is supplied with a drive signal including a first waveform and at least one second waveform. First waveform includes a first change from a first voltage to a second voltage, and a second change from the second voltage to a third voltage less than the first voltage. A second waveform begins after a time equal to one half of the natural oscillation period of liquid in a pressure chamber of the liquid ejection head. The second waveform includes a change from the third voltage to the second voltage and a change from second voltage to the third voltage after a time less than one half of the natural oscillation period.

According to one or more embodiments, a liquid discharge head comprises a substrate, a nozzle plate, and a damper member. The substrate comprises a plurality of pressure chambers. The nozzle plate is provided on a first surface of the substrate and comprises a plurality of nozzles, each of the plurality of nozzles aligned with a corresponding one of the plurality of pressure chambers. The damper member is provided on a second surface of the substrate and comprises a pressure wave absorbing material.

According to one embodiment, a liquid ejection device includes a nozzle plate in which nozzles for ejecting liquid are arranged, an actuator, a liquid supply unit, and a drive control unit. The actuator is provided in each of the nozzles. The liquid supply unit communicates with the nozzles. When one of a plurality of nozzles is given attention, the drive control unit gives drive signals to actuators of nozzles adjacent in an X direction and a Y direction, to drive the actuators at a timing shifted by a predetermined amount, such as half of a drive period, from a timing of an actuator of the nozzle given attention.

A liquid discharge apparatus includes an actuator and a drive circuit. The actuator is configured to cause liquid to be discharged from a nozzle. The drive circuit is configured to apply a waveform to the actuator during a discharge cycle in accordance with a discharge trigger and to cause a voltage of the actuator to be maintained at a value from an end of the discharge cycle until reception of a subsequent discharge trigger.

A drive circuit of a liquid ejecting device includes a first switch, a second switch, and a signal processing circuit. The first switch is connected between a first potential and an output terminal through which a drive signal is transmitted to an actuator of a liquid ejecting device. The second switch is connected between the output terminal and a second potential lower than the first potential. The signal processing circuit is configured to detect a difference between a waveform of a target drive signal and the drive signal waveform output at the output terminal, and to cause the first switch and the second switch to be off when an absolute value of the difference is less than a threshold value.

A liquid discharging head, having individual flow paths, a first manifold, a second manifold, a third manifold, a connecting flow path, and a bypass, is provided. The first manifold extends in a first direction and is provided commonly to the individual flow paths. The second manifold and the third manifold are located on one side and the other side of the first manifold in a second direction. The second manifold and the third manifold are provided commonly to a part of the individual flow path and another part of the individual flow path, respectively. The connecting flow path partly overlaps the first manifold in a vertical direction and connects one end of the second manifold and one end of the third manifold on one side in a third direction. The bypass extends in the vertical direction and connects the first manifold and the connecting flow path.