A piezoelectric actuator includes a piezoelectric layer and a conductor layer that is provided directly or indirectly on the piezoelectric layer. In plan view, the conductor layer includes a plurality of individual electrodes that are arranged with intervals therebetween and a plurality of wiring lines that extend from the plurality of individual electrodes. Each wiring line includes a wide portion and a first narrow portion. The wide portion includes a part positioned at a center of the wiring line in a length direction. The first narrow portion is disposed between the wide portion and one of the plurality of individual electrodes to which the wiring line is connected. The first narrow portion has a width less than a width of the wide portion.

A printhead is provided having an elongate support having a plurality of internal webs protruding from a base section to define a plurality of parallel fluid supply channels, a shim supported by the support and defining a plurality of rows of openings through which fluid from respective supply channels is supplied, and a plurality of elongate printhead modules supported serially on the shim. Each module defines a plurality of fluid supply passages through which fluid passes to fluid ejection nozzles from respective rows of the openings. Either end of each module defines complementary formations such that adjacent modules nest together.

A liquid ejection head, including: nozzles; and a supply passage through which a liquid is supplied to the nozzles, wherein the supply passage includes (a) a first flow passage and (b) a second flow passage connected to the first flow passage and including two sections that extend in different directions from a connected position at which the first flow passage is connected to the second flow passage, the liquid being supplied to the second flow passage from the first flow passage, wherein the second flow passage has a liquid flow resistance larger in a first section than in a second section, and wherein a protrusion protruding toward the first flow passage is provided on an inner wall surface of the second flow passage facing the first flow passage, for permitting the liquid to more easily flow from the first flow passage into the first section than the second section.

In some examples, a fluid ejection die includes a plurality of nozzles arranged in a plurality of nozzle columns, the plurality of nozzle columns distributed across a width of the fluid ejection die in a staggered manner, wherein nozzles of each respective nozzle column of the plurality of nozzle columns are spaced apart along a length of the fluid ejection die, wherein the plurality of nozzle columns includes a first pair of neighboring nozzle columns that are spaced by a first distance across the width. The plurality of nozzle columns includes a second pair of neighboring nozzle columns that are spaced by a second distance across the width, the second distance being larger than the first distance.

S1 is a sum of the areas of a plurality of individual electrodes formed on a first plane of a piezoelectric body of a liquid discharge head, S2 is an area of a first common electrode formed on a second plane, S3 is an area of a second common electrode formed on a third plane, D1 is a distance between a neutral plane and the first plane in a stacking direction, D2 is the distance between the neutral plane and the second plane in the stacking direction, and D3 is the distance between the neutral plane and the third plane in the stacking direction. Then, D1×S1+D2×S2>D3×S3 is satisfied. The liquid discharge head includes a plurality of conductor layers which are formed on the third plane, without contact with the second common electrode and without contact with each other.

An example recirculation fluid ejection device includes a first unit droplet generator including a first actuator and a first nozzle between a first and a second fluid feed hole, the first fluid feed hole located on a first channel and the second fluid feed hole and a first pump located on a second channel. The example device includes a second unit droplet generator including a second actuator and a second nozzle between a third and a fourth fluid feed hole, the third feed hole located on a third channel and the fourth fluid feed hole and a second pump located on a fourth channel. The first and the second actuators eject fluid at substantially the same backpressure. A first pressure measurable at an inlet of the first channel and the third channel are different from a second pressure measurable at an outlet of the second channel and the fourth channel.

A liquid ejecting device includes a flow path member, an actuator, a pump, and a controller. The flow path member includes a flow path configured to direct flow of a pseudoplastic liquid through the flow path member. The actuator is configured to cause droplets to be ejected. The pump is configured to cause the liquid to flow sequentially through a supply reservoir, a plurality of supply manifolds, a plurality of supply flow paths, and a plurality of pressure chambers. The controller is configured to adjust a flow rate of the liquid to a prescribed target flow rate. The flow path has a flow path shape in which an average viscosity of the liquid in the plurality of supply flow paths is less than or equal to half an average viscosity of the liquid in the plurality of supply manifolds when the flow rate is equal to the target flow rate.

A piezoelectric device includes a substrate on which a plurality of recesses are arranged in a first direction, a vibration plate, and a piezoelectric actuator having a first electrode, a second electrode and a third electrode, a fourth electrode, and a piezoelectric layer, in which a plurality of active portions are provided, the second electrode and the third electrode are provided from an edge of a region facing a recess to an outside of the recess, the first electrode is formed between the second electrode and the third electrode, the second electrode, the third electrode, and the fourth electrode configure common electrodes for the plurality of active portions, and the first electrode configures an individual electrode provided independently for each of the active portions.

A liquid discharge head is configured to discharge a liquid, and the liquid discharge head includes an actuator substrate and a holding substrate bonded to the actuator substrate. The actuator substrate includes a pressure generator, and a wiring electrode configured to electrically connect the pressure generator and an exterior of the liquid discharge head. The holding substrate includes an opening configured to expose the wiring electrode to the exterior of the liquid discharge head, and a detection surface adjacent to the opening, the detection surface having a higher reflectance than a surface of the wiring electrode of the actuator substrate.

In one example in accordance with the present disclosure, a fluid ejection die is described. The fluid ejection die includes a fluid feed slot to deliver fluid from a reservoir to an array of ejection chambers fluid connected to the fluid feed slot. Each ejection chamber includes at least one fluid actuator and an opening through which fluid is to be ejected. The fluid ejection die also includes a number of antechambers. An antechamber includes sidewalls that curve inward.