An inkjet printhead includes an inkjet nozzle with a main actuator and at least one peripheral actuator in the same firing chamber. A determination is made as to whether the inkjet nozzle has sat idle, e.g., not firing for a threshold period of time. When the inkjet nozzle has sat idle, both the main actuator and the peripheral actuator are activated to jet at least one ink drop to renew the inkjet nozzle to mitigate decap conditions. When the inkjet nozzle has not sat idle, only the main actuator is activated to jet ink drops.

A liquid jetting device comprising a plurality of ejection units each of which is arranged to eject a droplet of a liquid and comprises a nozzle, a liquid duct connected to the nozzle and an electro-mechanical transducer arranged to create an acoustic pressure wave in the liquid in the duct, the device further comprising an electronic control system arranged to receive a pressure signal from at least one of the transducers and to generate a transducer control signal on the basis of the received pressure signal and to control the transducers of said plurality of ejection units to operate in a mode of operation selected from a variety of different modes of operation, wherein the control system is arranged to detect an acoustic property of the liquid of the basis of the received pressure signal and to select the mode of operation in accordance with the detected property, the control system being arranged to deliver transducer control signals to the transducers, which control signals are derived from a common basic waveform that is specified by mode parameters, each mode of operation of the device is specified by a different set of mode parameters, the waveform comprises a jetting pulse and quench pulse following on the jetting pulse, and one of the mode parameters is a time delay between the start of the jetting pulse and the start of the quench pulse.

In accordance with an embodiment, an inkjet head comprises a pressure chamber, an actuator and a control section. The pressure chamber houses ink. The actuator is driven to expand or contract the volume of the pressure chamber in order to eject the ink from an opening of the pressure chamber. The control section applies an expansion pulse of which the width is 0.4 times-0.9 times as large as an AT which is half a natural vibration period during which nozzle negative pressure is changed in the pressure chamber and which expands the pressure chamber to the actuator, and applies a contraction pulse which contracts the pressure chamber to the actuator.

A drive signal generator includes a drive signal generator that generates a drive signal for driving a capacitive load. In the drive signal generator, a set of a first MOSFET and a second MOSFET which are electrically connected in series between a wire of a high potential and a wire of a low potential is arranged in plurality in series. A part or all of the first MOSFETs and the second MOSFETs in the plurality of sets have different sizes from each other.

A liquid ejecting device includes: an ejecting section group that includes a plurality of ejecting sections that receive a drive signal and eject a liquid; an ejection state check section that checks a state of a check target ejecting section that is an ejecting section among the plurality of ejecting sections; and a check target designation data management section that manages check target designation data that designates the check target ejecting section, the check target designation data management section including a first data-holding section and a second data-holding section, and having a first management mode in which the check target designation data management section updates data held by the first data-holding section and data held by the second data-holding section, and a second management mode in which the check target designation data management section updates the data held by the second data-holding section without updating the data held by the first data-holding section.

A liquid ejecting apparatus includes an ejecting unit that ejects liquid when a drive signal is supplied to the ejecting unit, a drive signal output unit that outputs the drive signal, a cooling unit that cools the drive signal output unit, and a power supply unit that supplies power to the cooling unit. The liquid ejecting apparatus has a first mode in which the drive signal output unit outputs a first drive signal of a first frequency, and a second mode in which the drive signal output unit outputs a second drive signal of a second frequency lower than the first frequency. An amount of power supplied by the power supply unit to the cooling unit in the first mode is larger than an amount of power supplied by the power supply unit to the cooling unit in the second mode.

A liquid discharge head is provided, which includes a nozzle plate which is formed with nozzles, and a channel member which is formed with pressure chambers and connecting channels for connecting the pressure chambers and the nozzles. The connecting channel includes a plurality of portions which have mutually different channel cross-sectional areas. The plurality of portions includes a first portion which is adjacent to the pressure chamber, and a second portion which is adjacent to the first portion, the first portion being interposed between the pressure chamber and the second portion. The first portion has the smallest channel cross-sectional area of those of the plurality of portions. S1≤0.3×S0 and S1≤0.7×S2 are fulfilled (S0: channel cross-sectional are of the pressure chamber, S1: channel cross-sectional area of the first portion, S2: channel cross-sectional area of the second portion).

An image forming apparatus is provided. The image forming apparatus includes a recording head to discharge a liquid on a recording medium while scanning in a main scanning direction and a sub-scanning direction relative to the recording medium. The recording head includes a first nozzle array and a second nozzle array. The first nozzle array discharges the liquid in a first discharge amount per unit time per unit length in a longitudinal direction. The second nozzle array discharges the liquid in a second discharge amount per unit time per unit length in the longitudinal direction. The second nozzle array is shorter than the first nozzle array in the longitudinal direction and disposed not overlapped with the first nozzle array in the main scanning direction. The second discharge amount is larger than the first discharge amount.

A wide array printhead module includes a plurality of printhead die, each of the printhead die includes a number of nozzles. The nozzles form a number of primitives. A nozzle firing heater is coupled to each of the nozzles. An application specific integrated circuit (ASIC) controls a number of activation pluses that activate the nozzle firing heaters for each of the nozzles associated with the primitives. The activation pulses are delayed between each of the primitives via internal delays and external delays to reduce peak power demands of the printhead die. The ASIC determines the internal delays within each printhead die.

An inkjet print head includes an ejection unit having a liquid chamber for holding an amount of liquid, a electromechanical transducer operatively coupled to the liquid chamber for generating a pressure wave in the amount of liquid and a nozzle in fluid communication with the liquid chamber for enabling a droplet of the amount of liquid to be ejected through the nozzle. A method for detecting an operating state of the ejection unit includes the consecutive steps of actuating the electromechanical transducer to generate a pressure wave in the liquid; actuating the electromechanical transducer to suppress a residual pressure wave in the liquid; sensing an amplitude of the residual pressure wave in the liquid; and based on the result of the sensing step determining that the ejection unit is (i) in an operative state if the amplitude of the residual pressure wave is below a threshold or (ii) in a malfunctioning state if the amplitude of the residual pressure wave is above the threshold.