A liquid ejection head is manufactured by forming on a substrate an energy generating element for ejecting a liquid, an integrated circuit for driving the energy generating element, a supply port for the liquid so as to penetrate through the substrate, an electrode for generating a liquid flow, and a flow path forming member having an ejection orifice for ejecting the liquid such that a flow path for the liquid is formed between the substrate and the flow path forming member. The electrode is formed over high and low of a stepped shape formed on the substrate in at least one step selected from the steps of forming the energy generating element, forming the integrated circuit and forming the supply port.

According to one embodiment, a waveform generating device includes a head driver configured to apply a driving signal to an actuator to discharge ink from a pressure chamber connected to a nozzle, the driving signal including a first portion for reducing an ink pressure in the pressure chamber and a second portion for increasing the ink pressure in the pressure chamber. The second portion is increased in potential by a first potential increase when ink pressure in the pressure chamber is at a maxima and the second portion is further increased in potential by a second potential increase when the ink pressure of the pressure chamber is at a negative value after the first potential increase.

An ink jet head includes a first pressure chamber to be filled with ink, an actuator, a drive circuit including a first switch configured to turn on and connect a first power supply voltage to a first electrode on the first pressure chamber 1, a second switch configured to turn on and connect the first power supply voltage to a second electrode on a second pressure chamber adjacent to the first pressure chamber, a third switch configured to turn on and connect the first electrode to a ground potential, and a fourth switch configured to turn on and connect the second electrode to the ground potential, and a nozzle plate including a discharge nozzle through which the ink from the first pressure chamber is to be discharged.

An inkjet head drive apparatus comprises a pressure chamber, an actuator, a nozzle and a drive signal output section. The pressure chamber accommodates an ink. The actuator increases or decreases volume of the pressure chamber through an applied a voltage. The nozzle is connected with the pressure chamber to eject the ink through the change in the volume of the pressure chamber. When an ejection pulse for the ejection of the ink from the nozzle is repeated for equal to or greater than three times, the drive signal output section outputs a drive signal having a driving waveform including an initial ejection pulse having a first voltage amplitude and the second ejection pulses and the pulses thereafter having a second voltage amplitude smaller than the first voltage amplitude to the actuator.

A liquid droplet ejecting device includes a channel member and an actuator. The channel member has a channel. The channel includes a nozzle and a pressure chamber communicating with the nozzle. The actuator is on the channel member and configured to apply a pressure to a liquid in the pressure chamber. A diameter of the nozzle and a natural frequency of the channel are parameters of the liquid droplet ejecting device to satisfy that (1) the actuator has a threshold drive frequency of 100 kHz or more, (2) the nozzle ejects a liquid droplet having a volume of 1.8 pl or more, and (3) the Ohnesorge number is 0.2 or more.

The present application is in at least one aspect directed to solving a problem of providing an inkjet recording device and an inkjet head driving method, in which instantaneous power consumption of a plurality of drive waveform generation circuits can be reduced while not requiring correction of an ink landing position without a complex structure. The problem is solved by dividing a plurality of pressure generating elements into first to n-th sets (n is an integer of 2 or more), and applying drive pulses to the pressure generating elements in the respective sets per every pixel period. The drive pulse combines any one of n time sharing drive waveforms (time sharing drive 1, 2, 3) with a common drive waveform (COM) as a rendering waveform, and the n time sharing drive waves are obtained by delaying a part of the rendering waveform by a time different from each other and have application timing deviated from each other.

An ink-jet recording apparatus includes: an ink-jet head provided with first and second nozzles for jetting a first ink and a second ink respectively, first and second drive elements which apply energy to the first and second inks respectively; a power supply circuit; and a controller. The controller estimates viscosity of the first ink in the first nozzle, controls the power supply circuit to generate a first drive voltage or a second drive voltage higher than the first drive voltage based on the viscosity of the first ink in the first nozzle estimated, drives the first and second drive elements by use of the drive voltage generated in the power supply circuit, and calculates a jetting amount of the first ink to be jetted from the first nozzle and a jetting amount of the second ink to be jetted from the second nozzle.

An ink jet head includes a pressure chamber, a nozzle plate including a nozzle, an actuator configured to cause an ink to be discharged from the pressure chamber via the nozzle, and a drive circuit configured to supply to the actuator an expansion signal, having a pulse width equal to a natural vibration cycle of the ink in the pressure chamber, that expands the pressure chamber to an expanded state from an initial state, a release signal, having a pulse width longer than the natural vibration cycle and shorter than three times the natural vibration cycle, that returns the pressure chamber to the initial state from the expanded state, and a contraction signal, having a pulse width longer than the natural vibration cycle and shorter than three times the natural vibration cycle, that contracts the pressure chamber to a contracted state from the initial state.

An actuator device includes: an actuator including a first element contact; and a wire member including (a) a first contact connected to the first element contact and (b) a first wire configured to conduct with the first contact. A first wide portion is formed at a distal end portion of the first wire at an edge portion of the wire member. The first wide portion is disposed beyond the first element contact in a wire direction of the first wire. The first contact is disposed at a basal end portion of the first wire. The basal end portion is located further from the edge portion of the wire member than the first wide portion. The first contact is connected to the first element contact.

The present invention has a problem of suppressing liquid gathering of an interpolation dot which interpolates a discharge defective nozzle and preventing deterioration of image quality, and the problem is solved by the present invention including: an inkjet head configured to separately discharge a large droplet, a medium droplet, and a small droplet from each of a plurality of nozzles; and a control unit which forms an image in a single-pass system by discharging the medium droplets from the plurality of nozzles respectively, and forms an interpolation dot to interpolate a discharge defective nozzle by discharging a droplet from a different nozzle when the discharge defective nozzle is present, the control unit forming the interpolation dot to interpolate the discharge defective nozzle with the use of the large droplet and forming at least one adjacent dot which is in contact with the interpolation dot with the use of the small droplet.