An ink jet apparatus includes a head, a circuit substrate, a cover frame, a heat sink, a fan, and a wall section. The cover frame supports the circuit substrate that has a drive circuit that drives the head inside of the cover frame and has a through hole. The heat sink that dissipates heat generated in the circuit substrate is disposed inside of the cover frame and has a part that is in direct or indirect contact with the circuit substrate. The fan generates air flow and is arranged such that the fan and the heat sink face to each other via the through hole. The wall section is disposed inside of the cover frame such that the air flow is not directly blown against the drive circuit and the air flow having changed a direction after blown against the heat sink is not blown against the drive circuit.

A liquid ejecting apparatus includes a drive element, and a drive circuit that outputs a drive signal that drives the drive element, wherein the drive circuit includes a modulation circuit that modulates a base drive signal to output a modulation signal, an amplifier circuit that amplifies the modulation signal to output an amplified modulation signal, a demodulation circuit that demodulates the amplified modulation signal to output the drive signal, and a substrate on which the modulation circuit, the amplifier circuit, and the demodulation circuit are provided, wherein the substrate includes a base material includes a metal and a first layer laminated on the base material, wherein the first layer includes a first propagation wire through which at least one of the amplified modulation signal and the drive signal propagates, and wherein the base material has a thickness greater than a thickness of the first layer.

The width by which the first, second heads overlap each other cross-sectionally along the first direction is greater than the width by which the fifth, sixth heads overlap each other cross-sectionally along the first direction.

There is provided a drive board a manufacturing cost of which can be reduced while enhancing a liquid ejection performance. The drive board according to an embodiment of the present disclosure is a drive board which is applied to a liquid jet head, and outputs a drive signal to a jet section, and includes a first wiring layer and a second wiring layer opposed to each other along a direction perpendicular to a board surface, at least one drive device which is mounted on the first wiring layer, and is configured to generate the drive signal, a first power supply wiring line which is arranged in the first wiring layer, and is a wiring line configured to supply drive power toward the drive device, a differential line which is arranged in the first wiring layer, and is a line configured to transmit a differential signal toward the drive device, and a second power supply wiring line which is arranged in the second wiring layer, which is electrically coupled to the first power supply wiring line via a first through hole, and is opposed to a first area in the differential line. A wiring width in the second power supply wiring line is larger than a line width of the first area in the differential line.

Misalignment of printing positions between print heads associated with thermal expansion is reduced without increasing a data processing load. To this end, printing element substrates in a reference head and an adjustment target head are adjusted to a target temperature, and a liquid is circulated through the print element substrates. After thermal expansion of the reference head and the adjustment target head reaches a steady state, a first printing region being a printing region of the reference head and a second printing region being a printing region of the adjustment target head in a longitudinal direction are obtained from an image printed by using all printing elements. Then, used regions to be used for actual printing are set among the printing elements arranged on the reference head and the adjustment target head based on the first printing region and the second printing region.

An inkjet printing system includes: (a) an inkjet printhead having a rigid elongate manifold with first and second parallel ink supply channels extending along a length of the manifold between respective ink ports positioned at opposite ends thereof; and a plurality of printhead chips mounted to a lower surface of the manifold, the ink supply channels supplying ink to the printhead chips via ink outlets defined in the lower surface. One end of the manifold has a first ink inlet port for the first ink supply channel and an ink outlet port for the second ink supply channel. The other end of the manifold has a first ink outlet port for the first ink supply channel and a second ink inlet port for the second ink supply channel. An ink delivery system is configured to flow ink along the first and second channels in opposite directions.

A head cooling device includes a refrigerant supplying portion, a switching portion, and a switch processing portion. The refrigerant supplying portion supplies a refrigerant to each of a plurality of recording heads, which ejects ink, through a supplying path. The switching portion can switch a corresponding supplying path of at least one of the plurality of recording heads. The switch processing portion controls the switching portion to switch the corresponding supplying path so as to decrease the temperature difference among the plurality of recording heads.

A liquid ejecting head includes: a plurality of head chips having nozzles; a holder holding the plurality of head chips; and a planar heater disposed on the holder and heating the holder, in which the heater includes an outer peripheral region along an outer edge of the holder and a middle region positioned inside the outer peripheral region in a plan view, and a heat generation amount per unit time of the outer peripheral region is larger than a heat generation amount per unit time of the middle region.

A printer includes a board configured to control a printing unit operating in the printer that performs printing on a medium, and a heat sink including a counter surface that is provided to face a board surface of the board and that has a shape with a length in a first direction X longer than a length in a second direction Y intersecting the first direction X in a plan view, and configured to receive heat generated in the board with the counter surface and dissipate the heat to the outside. The counter surface includes a slit penetrating the counter surface and extending in the second direction Y.

A liquid discharge head is provided in which heat of a heat sink is less apt to transfer to a head body. The liquid discharge head includes a head body 2a having a discharge hole for discharging a liquid therethrough, a driver IC 93 configured to control driving of the head body 2a, a casing 91 which is disposed on the head body 2a and has openings 91a and 91b on a side surface of the casing, and a heat sink 90 which is disposed on the openings 91a and 91b of the casing 91 and configured to dissipate heat generated in the driver IC 93, and a thermal insulation part 91e disposed between the heat sink 90 and the head body 2a. This makes it possible to reduce the likelihood that the heat of the heat sink 91e transfers to the head body 2a.