An example provides a fluid ejection device including a fluid feed slot, a fluid chamber between a nozzle layer and a passivation layer, and a printhead-integrated sensor to sense a property of a fluid in the fluid chamber. The sensor may include a ground electrode exposed to the fluid chamber through a via in the passivation layer.

A liquid ejecting apparatus is configured to drive a drive element that is driven in accordance with a drive signal for ejecting a plurality of liquid droplets such that the liquid droplets merge together before landing onto a medium. The drive signal includes a plurality of drive waveforms and a first connection waveform that is continuous from a second-to-last drive waveform and continuous to a last drive waveform and along which a potential of the drive signal is kept at a reference level. Pressure changes caused by the contraction waveform of the last drive waveform in a liquid present inside the pressure compartment are larger than pressure changes caused by the contraction waveform of the second-to-last drive waveform in the liquid present inside the pressure compartment. A period of the first connection waveform is 0.8 or more times as long as a natural vibration cycle of the ejecting portion.

A printing apparatus includes a printing head that includes a plurality of nozzles, each of which ejects an ink pushed out from a pressure chamber by driving of an actuator, a display unit, a detector that generates a residual vibration in the pressure chamber by imparting, to the actuator, a predetermined drive signal that prevents the nozzle from ejecting the ink, and, based on the residual vibration, performs, for each of the plurality of nozzles, defective nozzle detection processing of detecting a defective nozzle having ejection failure, and a display control unit that causes the display unit to display defective nozzle information including a position, in the printing head, of the defective nozzle detected by the detector.

Methods for ejecting fluids having a viscosity ranging from about 20 mPa-sec to about 100 mPa-sec at 22 C. from a micro-fluid ejection head. The methods include the steps of applying a heat signal to the ejection head for a first period of time to heat the ejection head to a first temperature that is about 20 C. above a steady state fluid ejection temperature for continuous or intermittent fluid ejection from the ejection head; and subsequently, applying a firing signal to ejection heaters on the ejection head during which fluid ejection from the ejection head occurs.

An inkjet device for controlled positioning of a droplet of a substance onto a substrate includes a print head having a nozzle configured to eject the droplet. A camera is configured to detect and generate images of the droplet after ejection of the droplet from the nozzle. If the droplet volume, velocity, flight path, viscosity or surface tension start to deviate from preset values, a computer is configured to correct for this in a closed loop manner. If the droplet fails to eject, the computer is configured to stop the inkjet device and an operator can maintain the print head. The computer is configured to determine viscosity and surface tension of the droplet from characteristics of the droplet identified from the droplet images, and the computer is configured to control the positioning of the droplet onto the substrate during the printing process based on the determined viscosity and surface tension.

A system and method for dispensing a fluid within an environment. The method includes the steps of: providing a dispensing system within an environment; discharging fluid from the dispensing system at a first, non-zero rate; detecting a change in the environment; and discharging fluid at a second rate after detecting the environmental change. The system comprises: a MEMS element coupled to a fluid reservoir and adapted to dispense fluid at a plurality of non-zero rates; at least one sensor; and a controller in communication with the MEMS element and at least one sensor and adapted to receive an output from the sensor and to alter the dispensing rate of the MEMS element according to the sensor output.

A print head ejecting a liquid with respect to a medium and assembled to a liquid ejecting apparatus includes: an ejecting portion ejecting the liquid by receiving a drive signal; an electrically erasable non-volatile memory; and a wireless communication module, in which history information changing in accordance with an operation state of the print head is stored in the non-volatile memory, and the wireless communication module transmits the history information in accordance with a request from an outside.

A liquid discharge apparatus includes: a liquid discharge head configured to discharge a liquid from a nozzle, the liquid discharge head including: a liquid chamber communicating with the nozzle; a pressure generator configured to deform the liquid chamber to apply pressure to the liquid in the liquid chamber; and circuitry configured to apply a drive signal to the pressure generator to drive the pressure generator, the drive signal including at least one drive pulse. The drive pulse includes: an expansion element to expand the liquid chamber to a first volume; a holding element to hold the first volume of the liquid chamber expanded by the expansion element for a predetermined time; and a contraction element to contract the liquid chamber from the first volume held by the holding element to a second volume.

A liquid ejection apparatus includes a first piezoelectric element, a first pressure chamber, a second piezoelectric element, a second pressure chamber, a nozzle flow path which communicates with the first pressure chamber and the second pressure chamber and which is provided with a nozzle, and a determination unit configured to determine a liquid state at the nozzle based on a first detection signal which represents a change in electromotive force of the first piezoelectric element after at least one of the first piezoelectric element and the second piezoelectric element is driven, and a second detection signal which represents a change in electromotive force of the second piezoelectric element after at least another of the first piezoelectric element and the second piezoelectric element is driven.

In a flow path unit, ink flows toward a recording head that ejects the ink. The flow path unit includes a flow path portion, a temperature adjustment unit, and a compression coil spring. The flow path portion is formed of metal and includes a supply pipe through which the ink flows. The temperature control unit heats the supply pipe. The compression coil spring is formed of metal and is attached to an inner surface of the supply pipe. The ink can come into contact with the compression coil spring, and the compression coil spring enables the ink to flow downstream in the supply pipe.