There is provided liquid discharging head including common liquid chambers each extends along first direction and arranged in second direction orthogonal to the first direction; and individual channels each communicates with one of the common liquid chambers and each has nozzle. The liquid discharging head has first and second ends in the second direction. The common liquid chambers include intermediate common liquid chamber interposed between two of the common liquid chambers and expanded common liquid chamber closest to the first end, length of the expanded common chamber in the second direction being longer than length of the intermediate common chamber in the second direction. The nozzles of the individual channels communicating with the expanded common chamber are positioned on a side of the second end with respect to the expanded common chamber without being positioned on a side of the first end with respect to the expanded common chamber.

There is provided a head unit including: a discharge section that includes a piezoelectric element driven by a driving signal and discharges a liquid; a first substrate; a second substrate; and a coupling member that electrically couples the first substrate and the second substrate, in which the coupling member includes a pin header having a plurality of insertion pins including a first insertion pin and a second insertion pin, and a holding section that holds the plurality of insertion pins in a state of being insulated, and a pin socket having the same number of a plurality of insertion holes as the plurality of insertion pins, which are provided corresponding to the plurality of insertion pins, and the coupling member electrically couples the first substrate and the second substrate by inserting the plurality of insertion pins into the corresponding plurality of insertion holes.

When a pressure of the liquid inside the common supply flow path is higher than a pressure of the liquid inside the pressure chamber, the adjustment portion changes the cross-sectional area to be a first cross-sectional area when a pressure difference, which is a difference between the pressure of the liquid inside the common supply flow path and the pressure of the liquid inside the pressure chamber, is a first pressure difference, and changes the cross-sectional area to be a second cross-sectional area larger than the first cross-sectional area when the pressure difference is a second pressure difference larger than the first pressure difference.

The control portion controls (i) a discharging operation of discharging the liquid from the plurality of nozzles by driving the plurality of energy generation elements and (ii) a pressurization operation of pressurizing the liquid from the individual flow path side in a state in which the plurality of nozzles are sealed by the sealing portion.

A liquid ejecting head includes a liquid flow channel including nozzles constituting a nozzle row configured to eject a liquid, a dummy flow channel including dummy nozzles constituting a dummy nozzle row not configured to eject liquid, and a closing section formed by an adhesive and closing the dummy flow channel.

A liquid discharge head includes an individual channel which includes: a nozzle; a pressure chamber; a descender of which one end in the first direction is nearer to the nozzle than the other end; and a second connecting channel connecting a second common channel and the one end of the descender. A central axis of the nozzle is positioned between the second common channel and a central axis of the descender in the second direction. The descender includes a first portion including the one end and a second portion positioned between the pressure chamber and the first portion in the first direction. In an end, of the descender, opposite to the second connecting channel in the second direction, an inner wall defining the one end of the first portion protrudes toward the second connecting channel in the second direction beyond an inner wall defining the second portion.

A liquid discharge head includes: a first pressure chamber group formed by pressure chambers arranged in a first direction; a second pressure chamber group formed by pressure chambers arranged in the first direction, and disposed side by side with the first pressure chamber group in a second direction; a first common channel extending in the first direction and communicating with the pressure chambers composing the first pressure chamber group; a second common channel extending in the first direction and communicating with the pressure chambers composing the second pressure chamber group; a first dummy pressure chamber disposed on one side in the first direction relative to the first pressure chamber group; and a second dummy pressure chamber disposed on the one side in the first direction relative to the second pressure chamber group.

A pagewide printhead for printing redundantly in four colors. First and second rows of printhead chips are mounted on a common ink manifold having four ink supply channels for supplying four colors of ink to the first and second rows of printhead chips. Dedicated ink outlets interconnect one ink supply channel of the ink manifold with a pair of redundant nozzle rows in each printhead chip.

A liquid discharge head includes: a nozzle plate having a nozzle from which a liquid is to be discharged in a discharge direction, the nozzle having a cylindrical hole having periodical convex portions and concave portions on a sidewall of the nozzle in the discharge direction, a diameter of an outermost portion of the nozzle in the discharge direction being smaller than an average diameter of minimum values and maximum values of diameters of the cylindrical shape. The average diameter is obtained by: Average diameter = (Sum of minimum values + Sum of maximum values) / (Count of minimum values + Count of maximum values).

A manifold includes: a liquid chamber including an elastic damper, the liquid chamber configured to store a liquid; multiple head couplers on a lower end of the liquid chamber, the multiple head couplers configured to be respectively coupled to multiple liquid discharge heads and spaced apart in a longitudinal direction of the liquid chamber; and a tank coupler on an upper end of the liquid chamber, the tank coupler configured to be coupled to a tank configured to store liquid to be supplied to or discharged from the manifold, wherein a length of the liquid chamber increases from the tank coupler on the upper end toward the multiple head couplers on the lower end of the liquid chamber.