A pagewide printhead for redundant printing has first and second rows of printhead chips mounted on a common ink manifold. The ink manifold has four ink supply channels for supplying ink to the first and second rows of printhead chips. Dedicated ink outlets interconnect one ink supply channel of the ink manifold with two color channels in each printhead chip.

A pagewide printhead for redundant printing has first and second rows of printhead chips mounted on a common ink manifold. The ink manifold has four ink supply channels for supplying ink to the first and second rows of printhead chips. Dedicated ink outlets interconnect one ink supply channel of the ink manifold with two color channels in each printhead chip.

Provided is an inkjet printing apparatus comprising: a print head that ejects ink; a tank that contains ink to be supplied to the print head; a floating body that floats on the liquid surface of the ink inside the tank; and an electrode pin that detects the level of the liquid surface inside the tank. The floating body includes an opening portion in which to insert the electrode pin, and a perimeter of the opening portion protrudes from a top surface side of the floating body.

Provided is an inkjet printing apparatus comprising: a print head that ejects ink; a tank that contains ink to be supplied to the print head; a floating body that floats on the liquid surface of the ink inside the tank; and an electrode pin that detects the level of the liquid surface inside the tank. The floating body includes an opening portion in which to insert the electrode pin, and a perimeter of the opening portion protrudes from a top surface side of the floating body.

The present disclosure refers to monitoring a printing fluid, in an example, a device is disclosed wherein the device N comprises a light emitter to illuminate a fluid line comprising a flowing printing fluid; an image sensor to capture a diagnostic image of the fluid line once it has been illuminated; and a processor connected to the detector being the processor to compare the diagnostic image to a baseline and to determine a printing fluid quality parameter based on the comparison.

The present disclosure refers to monitoring a printing fluid, in an example, a device is disclosed wherein the device N comprises a light emitter to illuminate a fluid line comprising a flowing printing fluid; an image sensor to capture a diagnostic image of the fluid line once it has been illuminated; and a processor connected to the detector being the processor to compare the diagnostic image to a baseline and to determine a printing fluid quality parameter based on the comparison.

A liquid ejecting head includes: a nozzle face; a filter; a downstream chamber that includes a first outlet and a second outlet for discharging the liquid, the downstream chamber being located downstream of the filter; a first flow passage that is in communication with the downstream chamber through the first outlet; a second flow passage that is in communication with the downstream chamber through the second outlet; and a common flow passage that is in communication with the first flow passage and the second flow passage, wherein, as viewed perpendicularly to the nozzle face, the first outlet is located at a position that is shifted from a center of the downstream chamber in a first direction, and the second outlet is located at a position that is shifted from the center of the downstream chamber in a second direction that is opposite of the first direction.

A liquid ejection apparatus includes a printing element board, supply and collection flow passages, a liquid feeding mechanism, and first and second bubble reservoir units. The printing element board includes a pressure chamber having an ejection port from which the printing element board ejects a liquid. The supply and collection flow passages communicate with the pressure chamber. The liquid feeding mechanism generates a difference in pressure between the supply and collection flow passages to supply the liquid from the supply flow passage to the pressure chamber and to recover the liquid in the pressure chamber from the collection flow passage. The first bubble reservoir unit connects the supply flow passage to the liquid feeding mechanism. The second bubble reservoir unit connects the collection flow passage to the liquid feeding mechanism. A volume of the first bubble reservoir unit is larger than a volume of the second bubble reservoir unit.

A liquid ejection apparatus includes a printing element board, supply and collection flow passages, a liquid feeding mechanism, and first and second bubble reservoir units. The printing element board includes a pressure chamber having an ejection port from which the printing element board ejects a liquid. The supply and collection flow passages communicate with the pressure chamber. The liquid feeding mechanism generates a difference in pressure between the supply and collection flow passages to supply the liquid from the supply flow passage to the pressure chamber and to recover the liquid in the pressure chamber from the collection flow passage. The first bubble reservoir unit connects the supply flow passage to the liquid feeding mechanism. The second bubble reservoir unit connects the collection flow passage to the liquid feeding mechanism. A volume of the first bubble reservoir unit is larger than a volume of the second bubble reservoir unit.

A liquid ejection head and a liquid ejection apparatus suppressing the occurrence of an ejection failure without increasing the size of the apparatus are provided. To this end, between a circulation unit and a supply flow path communicating with a pressure chamber, a flow path is provided, having a vertical cross-sectional area in a liquid circulation direction, which is double or more a vertical cross-sectional area in a liquid circulation direction in the supply flow path and having a flow path inner wall inclined with respect to the gravitational direction and whose component force of a normal vector has a component in the gravitational direction.