Provided is a liquid ejection head including plural liquid chambers arranged in rows, each liquid chamber being provided with an orifice configured to eject liquid filling the liquid chamber and an ejection energy generating element, wherein the liquid ejection head includes: a liquid supply path that extends in a direction that the plural liquid chambers are arranged and individually communicates with the plural liquid chambers; a direction change flow path that communicates with the liquid supply path and extends in a direction transverse to the liquid supply path; and a common supply flow path that communicates with the direction change flow path and extends in a direction transverse to the direction change flow path, such that the direction change flow path includes a body portion and at least one grooved flow path, which is narrower than the body portion.

A liquid ejecting apparatus including a liquid ejecting portion that ejects a liquid in a pressure chamber from a nozzle that communicates with the pressure chamber, a liquid supply flow path that supplies the liquid stored in a liquid storing portion to the liquid ejecting portion, a degas module provided in the liquid supply flow path, a vacuum degree adjustment mechanism configured to adjust a vacuum degree of the degas module, a state detecting mechanism configured to detect a state inside the pressure chamber, and a control portion that drives and controls the vacuum degree adjustment mechanism based on a detecting result of the state detecting mechanism.

In a case where air bubbles exist in ink at the time of circulating the ink within a liquid ejection module, the amount circulating ink runs short and stability of ejection is blocked. The liquid ejection module has: a pressure chamber that communicates with an ejection port and which stores a liquid; an energy generation element that produces energy for causing a liquid to be ejected from the ejection port; a supply flow path that supplies a liquid to the pressure chamber; a collecting channel that collects a liquid from the pressure chamber; a liquid sending chamber that connects to the collecting channel; a connection flow path that connects the liquid sending chamber and the supply flow path; and a liquid sending unit configured to circulate a liquid, and the liquid sending chamber has a continuously inclined structure.

An inkjet printing apparatus includes a tank in which ink is contained; a print head for ejecting ink supplied from the tank to perform print operation; a supply flow path for supplying ink from the tank to the print head; a collection flow path for collecting ink from the print head to the tank; and a pump provided in the supply flow path or the collection flow path. The pump is driven, during print operation, at a first speed to circulate ink within a circulation path including the tank, the supply flow path, the print head, and the collection flow path, and the pump is driven, from a start of the ink circulation until a lapse of predetermined time period, at a second speed which is faster than the first speed.

In a liquid ejection head, an ejection pressure is applied to a pressure chamber for liquid ejection from a nozzle. A descender extends in a first direction and includes a first end connected to the pressure chamber and a second end. A communication passage is connected to the second end, extends in a second direction crossing the first direction, and has a first dimension in the first direction. The nozzle is positioned at the communication passage such that a shortest distance between an outer periphery thereof and a center of the second end is greater than 0.5 times a second dimension of the second end in the second direction. When viewed in the first direction, the center of the second end and a center of a cross-section defined by the nozzle to be orthogonal to an extending direction of the nozzle intersect an axis of the communication passage.

An object is to provide a liquid ejection apparatus and a method of controlling a liquid ejection apparatus capable of preventing bubbles generated by kogation removal from interfering with the kogation removal. To this end, in a long liquid ejection head with a liquid circulated therethough, a pressure chamber is pressurized and a voltage is applied to a heat applying portion and an electrode to perform kogation removing cleaning.

An inkjet printing apparatus includes a tank in which ink is contained; a print head for ejecting ink supplied from the tank to perform print operation; a supply flow path for supplying ink from the tank to the print head; a collection flow path for collecting ink from the print head to the tank; and a pump provided in the supply flow path or the collection flow path. The pump is driven, during print operation, at a first speed to circulate ink within a circulation path including the tank, the supply flow path, the print head, and the collection flow path, and the pump is driven, from a start of the ink circulation until a lapse of predetermined time period, at a second speed which is faster than the first speed.

In some examples, a controller is to receive sensor data from a sensor associated with a fluid delivery system that delivers fluid from a fluid reservoir to a fluid conduit, determine, based on the sensor data, presence or integrity of a gas purger that is to be fluidically coupled to the fluid conduit, and issue an alert to indicate a gas purger anomaly condition based on the determining.

A liquid ejecting head unit includes a drive unit for ejecting a liquid inside a pressure chamber from a nozzle opening which communicates with the pressure chamber, a common liquid chamber which communicates with a plurality of the pressure chambers, a bubble return flow path for communicating with the common liquid chamber and discharging bubbles inside the common liquid chamber, a confluence point which communicates with a plurality of the bubble return flow paths, a collective return flow path for communicating with the confluence point and discharging the bubbles inside the plurality of bubble return flow paths, and a one-way valve which is provided part way down the bubble return flow path.

A liquid discharging head includes: a nozzle plate having a plurality of nozzles from which liquid is discharged; a channel member including a plurality of individual liquid chambers that lead to the plurality of nozzles, respectively, and including a plurality of circulation channels that lead to the plurality of individual liquid chambers, respectively; and a common liquid chamber member for forming a common liquid chamber that supplies liquid to the plurality of individual liquid chambers and for forming a circulation common liquid chamber that leads to the plurality of circulation channels.