A liquid ejection head and liquid ejection apparatus capable of suppressing deterioration in image quality without adding a member for heat radiation is to be provided. Therefore, in the liquid ejection head that ejects a circulating liquid, the second engagement part formed on the discharge port side has an elongated hole shape extending in the arrow B direction so as to support the liquid ejection unit support member in such a manner capable of allowing the thermal deformation.

There is provided a head unit including: a discharge section that includes a piezoelectric element driven by a first driving signal and discharges a liquid; a switching circuit that switches whether or not to supply the first driving signal; a first substrate that propagates the first driving signal and the discharge control signal to the switching circuit; a second substrate to which the first driving signal and the discharge control signal are supplied and which propagates the first driving signal and the discharge control signal to the first substrate; a first coupling member including a first conductive section that electrically couples the first substrate and the second substrate; and a second coupling member including a second conductive section that electrically couples the first substrate and the second substrate, in which a cross-sectional area of the first conductive section is larger than a cross-sectional area of the second conductive section.

There is provided a head unit including: a discharge section that includes a piezoelectric element driven by a driving signal and discharges a liquid; a first substrate; a second substrate; and a coupling member that electrically couples the first substrate and the second substrate, in which the coupling member includes a pin header having a plurality of insertion pins including a first insertion pin and a second insertion pin, and a holding section that holds the plurality of insertion pins in a state of being insulated, and a pin socket having the same number of a plurality of insertion holes as the plurality of insertion pins, which are provided corresponding to the plurality of insertion pins, and the coupling member electrically couples the first substrate and the second substrate by inserting the plurality of insertion pins into the corresponding plurality of insertion holes.

An ink heating device, which is incorporated in an inkjet printing apparatus, includes: a planar heating member bonded in a state where one surface of the planar heating member is thermally bonded to an outer surface of an ink tank storing ink; an elastic member, having a heat insulation property, is provided on the other surface of the planar heating member and presses the planar heating member against the ink tank; and a hardware processor that performs heating control on the planar heating member in a stepwise manner according to a stop time of a main body of the printing apparatus at a time of starting the main body of the printing apparatus.

A liquid ejecting head includes a liquid flow channel including nozzles constituting a nozzle row configured to eject a liquid, a dummy flow channel including dummy nozzles constituting a dummy nozzle row not configured to eject liquid, and a closing section formed by an adhesive and closing the dummy flow channel.

A liquid discharge head includes an individual channel which includes: a nozzle; a pressure chamber; a descender of which one end in the first direction is nearer to the nozzle than the other end; and a second connecting channel connecting a second common channel and the one end of the descender. A central axis of the nozzle is positioned between the second common channel and a central axis of the descender in the second direction. The descender includes a first portion including the one end and a second portion positioned between the pressure chamber and the first portion in the first direction. In an end, of the descender, opposite to the second connecting channel in the second direction, an inner wall defining the one end of the first portion protrudes toward the second connecting channel in the second direction beyond an inner wall defining the second portion.

A head alignment apparatus for determining a reference position using position synchronization and aligning a plurality of head modules according to the reference position, and a substrate treating system including the same are provided. The head alignment apparatus may include, a reference position determining unit for determining a first reference position of a head transfer, in which a plurality of inkjet head modules are installed; and a mounting position determining unit for determining a second reference position of the inkjet head module based on the first reference position so that the inkjet head module can be moved from a current position to a second reference position, wherein the reference position determining unit determines a first reference position using a first image sensor installed on the same plane as the inkjet head module and a second image sensor installed facing the inkjet head module.

A printing apparatus includes: a tank configured to contain ink; a print head configured to eject ink supplied from the tank; a supply flow path through which liquid is supplied from the tank to the print head; a collection flow path through which liquid is collected from the print head to the tank; a circulation unit configured to circulate ink inside a circulation flow path including the tank, the supply flow path, the print head, and the collection flow path; and a cooling unit configured to cool the tank by blowing.

A pagewide printhead for printing redundantly in four colors. First and second rows of printhead chips are mounted on a common ink manifold having four ink supply channels for supplying four colors of ink to the first and second rows of printhead chips. Dedicated ink outlets interconnect one ink supply channel of the ink manifold with a pair of redundant nozzle rows in each printhead chip.

A liquid ejecting head that has an ejection surface configured to eject a liquid includes a plurality of head chips that are long in a first direction. The plurality of head chips are arranged inside a virtual parallelogram including a first virtual side and a second virtual side that are in contact with at least one of the plurality of head chips and that extend in the first direction, and a third virtual side and a fourth virtual side that are in contact with at least one of the plurality of head chips and that extend in a second direction intersecting the first direction, and the ejection surface is not overlapped with an acute-angled portion of the virtual parallelogram when the ejection surface is viewed in a normal direction of the ejection surface.