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.

Various embodiments provide an ejection device for a fluid. The ejection device includes a first semiconductor wafer, housing, on a first side thereof, a piezoelectric actuator and an outlet channel for the fluid alongside the piezoelectric actuator; a second semiconductor wafer having, on a first side thereof, a recess and, on a second side thereof opposite to the first side, at least one inlet channel for said fluid fluidically coupled to the recess; and a dry-film coupled to a second side, opposite to the first side, of the first wafer. The first and the second wafers are coupled together so that the piezoelectric actuator and the outlet channel are set directly facing, and completely contained in, the recess that forms a reservoir for the fluid. The dry-film has an ejection nozzle.

According to an example, a base, a diaphragm, and a driving element are provided. The driving element includes a first electrode disposed on a second surface of the diaphragm, a second electrode opposing the first electrode, and a piezoelectric body interposed between the first electrode and the second electrode. In addition, an inter-wiring insulating film that covers the second surface of the diaphragm and the driving element, and an extracting electrode which is on the inter-wiring insulating film, are further provided. The inter-wiring insulating film includes a contact hole that exposes a part of the second electrode and through which the second electrode and the extracting electrode contact each other. The contact hole is disposed at a position which aligned with a solid portion of a circumferential wall of the pressure chamber in the base.

According to one embodiment in an ink jet head, the common electrodes for all the actuators, without overlapping with the first wiring pattern formed by individual electrodes, are connected to a second wiring pattern that passes between the outer peripheral portion of piezoelectric bodies, and a third wiring pattern that extends in a direction different from a direction of the second wiring pattern. The first wiring pattern and the third wiring pattern are electrically insulated at intersections thereof.

Provided are a method for manufacturing an ink jet head and an ink jet head. The method includes: arranging a vibrating plate on lower surface of a substrate; arranging a piezoelectric actuator on surface of the vibrating plate; arranging a protective film on surface of the piezoelectric actuator for sealing the piezoelectric actuator along with the vibrating plate, thus preventing the piezoelectric actuator from corrosion; etching the substrate and the vibrating plate to form a groove on the substrate at a position corresponding to the piezoelectric actuator, and form a liquid feeding hole on the substrate and vibrating plate; forming a pressure chamber and a nozzle orifice on lower surface of the vibrating plate, allowing the pressure chamber to cover the position where the piezoelectric actuator is arranged in the vibrating plate, enabling communication of the pressure chamber with the nozzle orifice and the liquid feeding hole.

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.

A liquid discharge apparatus includes a nozzle plate with nozzles and actuators and a drive controller. First and second nozzles are directly adjacent to each other in a first direction. First and third nozzles are directly adjacent to each other in a second direction. The drive controller is configured to apply a drive signal to first, second, and third actuators corresponding to the first, second, and third nozzles, respectively, during a drive cycle. A difference between a first timing at which the drive signal is applied to the first actuator and a second timing at which the drive signal is applied to the second actuator and a difference between the first timing and a third timing at which the drive signal is applied to the third actuator is an odd number multiple of a half of an inherent vibration cycle of the liquid discharge apparatus.

The invention relates to a method for detecting a failing ejection unit in an array of ejection units during printing of a digital image with liquid ink in a printer wherein a medium is transported relative to the array. The printed image is captured to density values on print positions of the printed image. The invented method comprises a step of adapting a halftone mask that is used in preparation of the digital image, such that from a variation in the image density around the line shaped defect the exact nozzle number associated with the failing ejection unit can be determined.

A liquid discharge head includes a pressure chamber in which liquid can be stored, a diaphragm forming a bottom wall of the pressure chamber and having a nozzle opening through which liquid supplied from the pressure chamber is discharged in a first direction, and a drive element on a lower surface of the diaphragm and configured to change a volume of the pressure chamber. A protective film covers the drive element and having a first opening corresponding in position with the nozzle opening, and a liquid repellent film covers the protective film and the lower surface of the diaphragm within the first opening. The liquid repellent film has an opening aligned with the nozzle opening and has the same diameter as the nozzle opening. The liquid repellent film on the drive element is thinner than the liquid repellent film on the lower surface of the diaphragm within the first opening.

A printing platform includes a printing engine with one or more printheads arranged such that the ink drops are jetted vertically upwards against the action of gravity; and a substrate transportation system where the normal to the surface in contact with the substrate is parallel and with opposite direction to the travelling direction of the jetted ink drops. It is necessary to counteract the weight of the substrate during the printing process to avoid it from falling under the action of gravity. This is achieved through any of a mechanical element that interferes with the falling of the substrate and that keeps it in place; or a system that generates adhesion forces between the element that transmits the motion to the substrate, typically a conveyor belt, and the substrate through the action of electrostatic forces, an air pressure differential between both faces of the substrate, or any other suitable mechanism.