A liquid discharging head includes a nozzle plate having a plurality of nozzles from which liquid is discharged; a plurality of individual liquid chambers that are communicably connected to the plurality of nozzles, respectively; a common liquid chamber that supplies liquid to the plurality of individual liquid chambers; and a circulation common liquid chamber that leads to a plurality of circulation channels. A part of the common liquid chamber overlaps the circulation common liquid chamber from a direction in which liquid is discharged from the nozzles, and another part of the common liquid chamber overlaps the circulation common liquid chamber from a direction orthogonal to both the direction in which liquid is discharged from the nozzles and a direction in which the nozzles are aligned.

Printheads for a jetting apparatus. In one embodiment, a printhead comprises a plurality of flow-through jetting channels each configured to jet a print fluid out of a nozzle. The printhead further includes a supply manifold fluidly coupled to the flow-through jetting channels, a return manifold fluidly coupled to the flow-through jetting channels, and one or more bypass manifolds fluidly coupled between the supply manifold and the return manifold.

Printheads and design of printheads. In one embodiment, a printhead comprises a plurality of jetting channels, and a manifold apparatus fluidly coupled to the jetting channels. For each jetting channel, the printhead includes a first fluid path between the jetting channel and the manifold apparatus, and a second fluid path between the jetting channel and the manifold apparatus. The jetting channel is configured to jet a print fluid via pressure waves generated in a pressure chamber of the jetting channel. Lengths of the first fluid path and the second fluid path are different by a threshold length so that an arrival time of the pressure waves at the manifold apparatus are different by a threshold time.

A piezoelectric body that is driven to apply pressure to a liquid in the plurality of pressure chambers, and contains lead atoms, a first electrode that is provided on a first surface of two surfaces of the piezoelectric body, a second electrode that is provided on a second surface opposite to the first surface of the two surfaces of the piezoelectric body, a drive wiring that is electrically coupled to the first electrode and the second electrode, and applies a voltage for driving the piezoelectric body, a resistor that is formed of the same material as any of the first electrode, the second electrode, and the drive wiring to measure a temperature of the liquid in the plurality of pressure chambers, and a diffusion suppression layer that is provided between the resistor and the piezoelectric body to suppress diffusion of lead atoms contained in the piezoelectric body into the resistor.

A liquid discharge apparatus includes: a head including a pressure chamber and a nozzle, the head configured to discharge a liquid in the pressure chamber from the nozzle; circuitry configured to generate a drive waveform including multiple drive pulses to be applied to the head, the drive waveform successively including, in time series: a non-discharge pulse that does not cause the head to discharge the liquid from the nozzle; a latter discharge pulse after the non-discharge pulse, the latter discharge pulse including a contraction waveform element that contracts the pressure chamber to discharge the liquid from the nozzle; and a contraction waveform including the contraction waveform element that contracts the pressure chamber.

A liquid circulation device includes a circulation passage, a liquid feeding device, a pressure sensor, and control circuitry. Through the circulation passage, liquid circulates to be supplied to and collected from a circulatory liquid discharge head. The liquid feeding device is configured to circulate the liquid through the circulation passage. The pressure sensor is configured to detect a pressure of the circulation passage. The control circuitry configured to acquire a characteristic indicating a relationship among a drive amount of the liquid feeding device, discharge information of the liquid discharged from the liquid discharge head, and a pressure detection value of the circulation passage; and change, based on the characteristic acquired, at least one of a control parameter and a calculation expression used to control the liquid feeding device.

A liquid discharge head includes a nozzle to discharge a liquid, a pressure generation chamber facing the nozzle, a common liquid chamber to supply the liquid to the pressure generation chamber, a fluid restrictor communicating with the pressure generation chamber, and a guide channel communicating with the fluid restrictor and the common liquid chamber. The guide channel includes a first adjacent portion communicating with the fluid restrictor. The pressure generation chamber has a first resonance period, and the guide channel has a second resonance period different from the first resonance period.

An ink jet head includes a piezoelectric element that is driven in a d33 mode, a pressure generation chamber in which a pressure is generated by the piezoelectric element, and an individual ink supply flow passage that through which the ink is supplied to the pressure generation chamber. The ink jet head includes an individual ink discharge flow passage that through which the ink is discharged from the pressure generation chamber, and a nozzle that ejects the ink from the pressure generation chamber. In a cross-sectional view in a direction orthogonal to an arrangement direction of the nozzle, inner diameters of the pressure generation chamber, the individual ink supply flow passage, and the individual ink discharge flow passage are shorter on a part close to the nozzle than a part close to the piezoelectric element side. Accordingly, an ink jet head capable of ejecting high-viscosity ink can be provided.

A liquid discharge head includes: a diaphragm having a nozzle; a substrate including a pressure chamber communicating with the nozzle; a piezoelectric body over the diaphragm, the piezoelectric body configured to deform at least a part of an edge of the nozzle; and a vibration absorbing portion in the diaphragm.

An image-recording apparatus includes: a first tank defining a first storage chamber; a second tank defining a second storage chamber; a conveying mechanism for conveying sheets along a conveying path extending in a depthwise direction and a widthwise direction perpendicular to a vertical direction and the depthwise direction; and a recording head including a nozzle. Liquid in the first storage chamber is supplied through a communication port to the second storage chamber and then to the recording head through a liquid outlet port. The second storage chamber is positioned further in a first depthwise direction relative to the nozzle and further in a first widthwise direction relative to the conveying path. A volume of a prescribed space above a liquid level equal to a height of the communication port in the second storage chamber is greater than that of a liquid channel between the liquid outlet port and the nozzle.