An attachment device for attaching an electronic assembly to a base module (e.g. print head) of a printing device can include a carrier plate of the assembly and a support body of the base module that has a groove into which the carrier plate may be inserted and arrested by means of a latch that engages in a recess of the carrier plate. The attachment device advantageously enables an efficient and reliable attachment of the assembly to the base module.

Provided is a liquid ejection apparatus capable of cooling a control board of a liquid ejection head without cooling a liquid supply path. Ae liquid ejection unit ejects ink onto paper. Ae control board controls the operation of the liquid ejection unit. Ae head housing covers and houses the control board inside thereof. Ae liquid supply path supplies ink to the liquid ejection head. Ae main body housing covers and houses a portion of the liquid ejection head except for the liquid ejection unit. A fan causes air to flow between the main body housing and the head housing. The liquid supply path is inserted from the outside to the inside of the main body housing in the vicinity of the liquid ejection head, and is connected to the liquid ejection head.

A liquid discharge head includes a connector component, a head unit, and a relay module component. The connector component is electrically connectable to a drive board. Ink from an ink chamber is supplied to the head unit. The relay module component is between the connector component and the head unit. The relay module component is detachable from the connector component and the head unit. The relay module component includes a channel to supply the ink supplied from the ink chamber to the head unit.

There is provided a liquid discharge head including a first channel unit and a second channel unit. The first channel unit includes: a first joining surface; a tube disposed on an opposite surface opposite to the first joining surface; an outside portion; and a coupling portion. The second channel unit is joined to the first joining surface. An end of the outside portion and an end of the coupling portion in an orthogonal direction orthogonal to the first joining surface extend to an identical position in the orthogonal direction. The tube includes a circumferential portion that is exposed outside and extends in the orthogonal direction to the identical position to which the end of the outside portion and the end of the coupling portion extend.

The communication plate has a first layer that defines a wall surface of the communication flow channel, a second layer stacked on a side of the first layer opposite to the wall surface, and a third layer stacked on a side of the second layer opposite to the first layer, and the thermal expansion coefficient of the second layer is smaller than the thermal expansion coefficient of the first layer and is smaller than the thermal expansion coefficient of the third layer.

A liquid ejection head includes: head units arranged in a first direction; first individual heat dissipators each corresponding to one of the head units and disposed on a first side of the head unit in a second direction; and a first common heat dissipator disposed on the first side of the head units in the second direction. The first common heat dissipator extends in the first direction and shared among the head units. Each head unit includes: a unit body including an actuator; and a first driver integrated circuit disposed on the first side of the unit body in the second direction. Each of the first individual heat dissipators is disposed between the first driver integrated circuit and the first common heat dissipator of the head unit so as to be in thermal contact with the first driver integrated circuit and the first common heat dissipator.

A liquid discharge head is provided which comprises a head body, a casing and a thermal insulator. The head body comprises a surface having one or more holes configured to discharge liquids therethrough. The casing, disposed on the head body, comprises a heat generator configured to generate heat and a heat sink configured to dissipate the heat. The thermal insulator is between the heat sink and the head body.

A liquid discharging apparatus includes a head unit having a liquid discharging head that has a driving element, a position detection circuit that outputs a position information signal indicative of a position of the liquid discharging head, a first circuit that controls drive of the driving element based on a first signal, and a first conversion circuit that converts a first optical signal into the first signal; and a driving circuit having a second circuit that outputs a second signal, a second conversion circuit that converts the second signal into the first optical signal, a first cable, and a second cable, in which the first cable connects the first conversion circuit to the second conversion circuit, and propagates the first optical signal, and the second cable electrically couples the position detection circuit to the second circuit, and propagates the position information signal.

There is provided a liquid discharge head including: a communication plate having a plurality of descenders in respective communication with a plurality of nozzles, a pressure chamber plate being stacked on the communication plate and having a plurality of pressure chambers, a piezoelectric element arranged in a position overlapping with the pressure chambers in a stacking direction, and a discharge common channel extending in an array direction and being in communication with the plurality of pressure chambers. The discharge common channel includes: a first discharge portion formed in the communication plate; and a second discharge portion formed in the pressure chamber plate and in communication with the first discharge portion, the second discharge portion reaching as high as to a surface of the pressure chambers at the side of the piezoelectric element along the stacking direction.

A head unit has: a first member in which a pressure chamber that stores a liquid to be discharged from a nozzle is formed; a piezoelectric element disposed on the first member and configured to deform in response to a driving signal; a first substrate disposed on the first member so as to cover the piezoelectric element; an integrated circuit disposed on the first substrate, and configured to supply the driving signal to the piezoelectric element; a second member disposed on the first member, and the second member including a holding chamber configured to hold the liquid, and a heat dissipation opening configured to dissipate heat of the integrated circuit; and a third member formed from a metal, the third member being disposed on the second member. The heat dissipation opening is located between the integrated circuit and the third member.