A liquid discharge head is provided, which includes a nozzle plate which is formed with nozzles, and a channel member which is formed with pressure chambers and connecting channels for connecting the pressure chambers and the nozzles. The connecting channel includes a plurality of portions which have mutually different channel cross-sectional areas. The plurality of portions includes a first portion which is adjacent to the pressure chamber, and a second portion which is adjacent to the first portion, the first portion being interposed between the pressure chamber and the second portion. The first portion has the smallest channel cross-sectional area of those of the plurality of portions. S1≤0.3×S0 and S1≤0.7×S2 are fulfilled (S0: channel cross-sectional are of the pressure chamber, S1: channel cross-sectional area of the first portion, S2: channel cross-sectional area of the second portion).

A print head has an ink slot and a sensing chamber having a first port connected to the fluid slot and a second port. The sensing chamber contains an ink level sensor. A recirculation passage extends from the fluid slot and is fluidly coupled to the second port. A fluid pump circulates fluid through the recirculation passage.

A fluid ejection device includes a fluid slot, at least one fluid ejection chamber communicated with the fluid slot, a drop ejecting element within the at least one fluid ejection chamber, a fluid circulation channel communicated with the fluid slot and the at least one fluid ejection chamber, and a fluid circulating element communicated with the fluid circulation channel. The fluid circulating element is to provide on-demand circulation of fluid from the fluid slot through the fluid circulation channel and the at least one fluid ejection chamber.

A fluid ejection device includes a fluid slot, a plurality of fluid ejection chambers communicated with the fluid slot, a plurality of drop ejecting elements one of each within one of the fluid ejection chambers, a fluid circulation channel communicated with the fluid slot and one or more of the fluid ejection chambers, and a fluid circulating element communicated with the fluid circulation channel. The fluid circulating element is to provide continuous circulation of fluid from the fluid slot through the fluid circulation channel and the one or more of the fluid ejection chambers.

A liquid ejection head includes a support member extending in a first direction, a print element board having an ejection port through which liquid is ejected, and first and second members arranged in the support member adjacent to each other along the first direction, each having a supply path extending in the first direction. The print element board element generates energy used for ejection of the supply paths supplied liquid. The first member includes an outlet port through which the supplied liquid flows out. The second member includes an inlet port through which the liquid from the outlet port flows. The outlet port is provided near a first member supply path end portion on the support member side on which the second member is provided. The inlet port is provided near a second member supply path end portion on the support member side on which the first member is provided.

A recording element substrate includes: a substrate on which a plurality of energy generating elements that generate energy used for ejecting liquid are arranged side by side, an ejection port forming member in which ejection ports are formed at positions corresponding to the plurality of energy generating elements, a plurality of supply passages which are channels extending in a thickness direction of the substrate and through which liquid is supplied to the energy generating elements, and a support member that is formed between the substrate and the ejection port forming member and supports the ejection port forming member, in which supply ports that are apertures of the plurality of supply passages are linearly arranged side by side on the substrate, and a plurality of support members are provided side by side between adjacent supply ports on the substrate in a direction in which the supply ports are aligned.

A liquid discharge head is configured to achieve decrease in temperature difference in the liquid discharge head, and includes a recording device including the liquid discharge head. The liquid discharge head includes a channel member having a plurality of discharge holes, a plurality of pressurization chambers, and a plurality of common channels, and a plurality of pressurizing parts. The plurality of common channels extends in a first direction and configures a common channel group aligned in a second direction crossing the first direction, the common channels are connected with the plurality of pressurization chambers disposed along the common channels among the plurality of pressurization chambers, and the channel member is disposed outside, in the second direction, with respect to the common channel group, and further includes a first end channel extending in the first direction, and the first end channel is lower in channel resistance than the common channels.

There is provided a printer including first to fourth head chips, and first and second rollers. The first to fourth head chips are arranged at intervals in a second direction orthogonal to a first direction. A nozzle, of nozzles arranged in a second head chip N and used for printing, which is positioned closest to the one side in the second direction is referred to as a nozzle A. A nozzle, of nozzles arranged in a fourth head chip N and used for printing, which is positioned closest to the one side in the second direction is referred to as a nozzle B. The nozzle A is arranged closer to the one side in the second direction than the nozzle B and the first roller is arranged closer to the other side in the second direction than the second roller.

A fluid ejection device includes a fluid slot, a plurality of fluid ejection chambers communicated with the fluid slot, a plurality of drop ejecting elements one of each within one of the fluid ejection chambers, a plurality of fluid circulation channels each communicated with the fluid slot and one or more of the fluid ejection chambers, and a plurality of fluid circulating elements each communicated with one or more of the fluid circulation channels. The fluid circulating elements are to provide intermittent circulation of fluid from the fluid slot through the one or more of the fluid circulation channels and the one or more of the fluid ejection chambers.

A fluid ejection device may include fluid ejectors, fluid pumps to circulate fluid to the fluid ejectors, a first actuation signal line and at least one second actuation signal line. The first actuation signal line is connected to each of the fluid ejectors and each of the fluid pumps along which a first signal is transmittable to actuate a selected one of fluid ejectors and the fluid pumps. The at least one second actuation signal line is connected to the fluid pumps along which a second signal is transmittable to actuate a selected one of the fluid pumps.