In an inkjet printer of the present invention, an air blowing outlet is formed around a slit through which ink droplets pass in a cap of a head cover, and air is blown toward a printing object from the blowing outlet. The air blowing outlet is formed independent of the slit, and the direction in which the air is blown is substantially parallel to the flight direction of ink droplets, and thus hardly any blown air meets the ink droplets that have passed through the slit and are flying toward the printing object. On the other hand, ink particles that have rebounded off the printing object are repelled by the air blown from the blowing outlet, and thus the amount of ink particles entering the head cover via the slit is suppressed.

A liquid ejecting system includes a head unit that includes a pressure chamber, a drive element driven by an applied drive waveform, a vibration plate that vibrates by drive of the drive element, and a nozzle through which a liquid is ejected by a pressure applied in the pressure chamber by vibration of the vibration plate, and an input portion to which an input parameter for detecting an ejection failure of the liquid based on residual vibration of the vibration plate is input from a server through a network connection portion.

A liquid ejecting system includes a head unit that includes a pressure chamber, a drive element driven by an applied drive waveform, a vibration plate that vibrates by drive of the drive element, and a nozzle through which a liquid is ejected by a pressure applied in the pressure chamber by vibration of the vibration plate, and an input portion to which an input parameter for detecting an ejection failure of the liquid based on residual vibration of the vibration plate is input from a server through a network connection portion.

A device for forming and ejecting drops of an ink jet of a CIJ printing machine, this device including: a cavity for containing an ink and including an end provided with a nozzle (10) for ejecting ink drops, actuator means (21, 22, 32, 41, 42), in contact with the cavity, in which device the jet velocity modulation, from the nozzle (10), has a value Vj(f.sub.t) at the operating frequency of the cavity and the actuator, and this jet velocity modulation, at the temperature of 15 C. and at the temperature of 35 C., does not vary, in a frequency range of 5 kHz about the operating frequency f.sub.t, outside the range of between 0.25 Vj(f.sub.t) and 4 Vj(f.sub.t).

A device for forming and ejecting drops of an ink jet of a CIJ printing machine, this device including: a cavity for containing an ink and including an end provided with a nozzle (10) for ejecting ink drops, actuator means (21, 22, 32, 41, 42), in contact with the cavity, in which device the jet velocity modulation, from the nozzle (10), has a value Vj(f.sub.t) at the operating frequency of the cavity and the actuator, and this jet velocity modulation, at the temperature of 15 C. and at the temperature of 35 C., does not vary, in a frequency range of 5 kHz about the operating frequency f.sub.t, outside the range of between 0.25 Vj(f.sub.t) and 4 Vj(f.sub.t).

A device for forming and ejecting drops of an ink jet of a CIJ printing machine, this device including: a cavity for containing an ink and including an end provided with a nozzle (10) for ejecting ink drops, actuator means (21, 22, 32, 41, 42), in contact with the cavity, in which device the jet velocity modulation, from the nozzle (10), has a value Vj(f.sub.t) at the operating frequency of the cavity and the actuator, and this jet velocity modulation, at the temperature of 15 C. and at the temperature of 35 C., does not vary, in a frequency range of 5 kHz about the operating frequency f.sub.t, outside the range of between 0.25Vj(f.sub.t) and 4Vj(f.sub.t).

A binary array ink jet printhead assembly includes a cavity for containing ink, nozzle orifices in fluid communication with the cavity for passing the ink from the cavity to form droplets, the nozzle orifices extending along a length of the cavity, and an electrode assembly. The electrode assembly includes a front face configured to be disposed generally parallel to a plurality of droplet paths of droplets from the nozzle orifices. A plurality of charge electrodes are disposed on the front face, each charge electrode corresponding to a droplet path and disposed parallel to the droplet path. Circuitry is disposed on the electrode assembly, wherein each electrode is electrically connected to the circuitry. The circuitry is further in electrical connection to a connector for connecting the electrode assembly to a controller for the printhead.

An inkjet recording device automatically determines an excitation voltage of a piezoelectric element for formation of ink droplets. An excitation voltage value is applied to the piezoelectric element of a nozzle over a plurality of sweeping events. A charge voltage is applied to ink droplets generated by the applied excitation voltage value in a plurality of arbitrary printing phases to give an electric charge thereto. A charge amount given to the ink droplets is detected by a sensor to obtain a printing phase. When the relationship of a current printing phase to a previous printing phase detected for each sweeping event is reversed from an increasing side to a decreasing side and two decrease determinations of the printing phase are established in succession, an excitation voltage value corresponding to the printing phase of the sweeping event immediately before the first decrease determination is set as a final excitation voltage value.

An inkjet recording device automatically determines an excitation voltage of a piezoelectric element for formation of ink droplets. An excitation voltage value is applied to the piezoelectric element of a nozzle over a plurality of sweeping events. A charge voltage is applied to ink droplets generated by the applied excitation voltage value in a plurality of arbitrary printing phases to give an electric charge thereto. A charge amount given to the ink droplets is detected by a sensor to obtain a printing phase. When the relationship of a current printing phase to a previous printing phase detected for each sweeping event is reversed from an increasing side to a decreasing side and two decrease determinations of the printing phase are established in succession, an excitation voltage value corresponding to the printing phase of the sweeping event immediately before the first decrease determination is set as a final excitation voltage value.

A head unit includes a piezoelectric element displaced according to a driving signal to cause a liquid to be ejected, a driving signal generation unit that generates the driving signal, a residual vibration signal generation circuit that outputs a change in an electromotive force of the piezoelectric element according to residual vibration, in a pressure chamber in communication with a nozzle, that occurs after supply of the driving signal, as a residual vibration signal, an analog differential residual vibration signal generation circuit that converts the residual vibration signal into an analog differential residual vibration signal, a demodulation circuit that demodulates the analog differential residual vibration signal and outputs a demodulated signal, an AD converter that converts the demodulated signal into a digital signal, and a determination unit that determines, based on the digital signal, a state in the pressure chamber.