Hewlett-packard Development Company, L.p.

Jacob Lum

Jeremy Sells

Garrett E Clark

Si-lam Choy

Alexander N Govyadinov

James A Feinn

Jeffrey R Pollard

Tsuyoshi Yamashita

Si-Lam J Choy

Mengqian Lu

A fluid ejection die may include a fluid actuator, a substrate supporting the fluid actuator, a chamber layer supported by the substrate and a bypass passage in the substrate. The substrate may include a closed inlet channel having an inlet opening for connection to an outlet of a fluid source and an outlet channel having an outlet opening of a first size for connection to an inlet of the fluid source. The chamber layer includes a recirculation passage to supply fluid for ejection by the fluid actuator through an ejection orifice and to circulate fluid across the fluid actuator from the closed inlet channel to the outlet channel. The bypass passage is of a second size less than the first size and connects the inlet channel to the inlet of the fluid source while bypassing any fluid actuator provided for ejecting fluid through an ejection orifice.

Recirculation bypass

A fluidic die may include a fluid channel layer defining a number of fluid channels therein, a slot layer disposed on a side of the fluid channel layer, and a first fluid slot and a second fluid slot defined in the slot layer. At least one of the fluid channels fluidically couples the first fluid slot to the second fluid slot. The first fluid slot and the second fluid slot are defined in the slot layer along a length of the fluidic die.

Fluidic dies

A fluid-ejection element of a fluid-ejection device includes a chamber layer having a pair of chambers fluidically disconnected from one another within the chamber layer. The fluid-ejection element includes a tophat layer over the chamber layer and fluidically connecting the chambers to define a fluid recirculation path between the chambers. The fluid-ejection element includes a nozzle common to both the chambers.

Fluid-ejection element between-chamber fluid recirculation path

An example printhead includes a circulation channel having an inlet for receiving a fluid and an outlet for expelling the fluid, a first nozzle fluidically coupled to the circulation channel, the first nozzle being operable at a first absolute pressure, and a second nozzle fluidically coupled to the circulation channel, the second nozzle being operable at a second absolute pressure, the absolute second pressure being lower than the first absolute pressure. The absolute pressure in the circulation channel decreases as the fluid flows from the inlet to the outlet, and the first nozzle is positioned closer to the inlet of the circulation channel than the second nozzle.

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Corvallis, OR, United States of America

Jacob Lum