A liquid discharging head is provided with: individual channels; a first common channel; and a second common channel. The individual channels include: first individual channels which have first pressure chambers and which are aligned in a second direction to form a first individual channel array, and second individual channels which have second pressure chambers and which are aligned in the second direction to form a second individual channel array; the first individual channel array and the second individual channel array are arranged in a third direction. The first common channel communicates with both of the first individual channels and the second individual channels; and the first pressure chambers and the second pressure chambers do not overlap with the second common channel in a first direction, and do not overlap with each other in the second direction.

A stress caused in an actuator member with respect to input or output of heat is reduced. There is provided a liquid jet head including an actuator member having a pressure chamber, a low rigidity support part which is disposed at one side with respect to the actuator member, and is coupled to the actuator member, and a high rigidity support part which is disposed at the other side opposite to the one side with respect to the actuator member, and is coupled to the actuator member. The high rigidity support part has a high rigidity part which includes a head constituent member of the liquid jet head higher in linear expansion coefficient and Young's modulus than the actuator member, and which reduces a thermal deformation of the high rigidity support part in a direction of extension or contraction of the actuator member with respect to input or output of heat to or from the liquid jet head to be smaller than a thermal deformation exhibited in the direction of the extension or the contraction by the head constituent member with respect to the input or the output of the heat. The low rigidity support part is lower in rigidity in the direction of the extension or the contraction than the actuator member.

A flow channel member includes a first flow channel member non-transmissive of ultraviolet light and absorbent of laser light, a second flow channel member non-transmissive of ultraviolet light and absorbent of laser light, the second flow channel member being stacked on the first flow channel member to define a flow channel for liquid to flow between the second flow channel member and the first flow channel member, and a third flow channel member transmissive of laser light, the third flow channel member being fixed to the first flow channel member and the second flow channel member in such a manner as to close a gap between the first flow channel member and the second flow channel member.

A recording device includes a recording unit configured to perform recording on a medium, and a discharge tray located above the recording unit in a height direction of the recording device and configured to support the medium discharged after recording is performed thereon, and a flow path of air for cooling a cooling target is formed along a lower surface of the discharge tray. The recording unit is an example of the cooling target.

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.

A liquid ejection head includes a flow channel structure, a supply channel structure, a piezoelectric element, a sealing substrate, and a heater. The flow channel structure defines an ejection channel including an individual channel and a manifold. The individual channel has a nozzle and a pressure chamber in which pressure is applied to liquid for causing the liquid to be ejected from the nozzle. The supply channel structure defines a supply channel configured to allow the liquid to flow therethrough to the ejection channel. The piezoelectric element is positioned on an upper surface of the flow channel structure and facing the pressure chamber via a vibration plate. The sealing substrate is made of a material having a higher thermal conductivity than the supply channel structure. The sealing substrate surrounds the piezoelectric element on the flow channel structure to seal the piezoelectric element. The heater is disposed at the sealing substrate.

A liquid ejection head includes a flow channel structure, a supply channel structure, and a particular heater. The flow channel structure defines an ejection channel that leads liquid toward a plurality of nozzles arranged in a nozzle row along a first direction. The supply channel structure defines a supply channel configured to allow liquid to flow therefrom to the ejection channel. The particular heater is configured to heat liquid. The flow channel structure is made of inorganic material having a higher thermal conductivity than material used for the supply channel structure. The flow channel structure includes an end portion protruding outward relative to a side surface of the supply channel structure. The particular heater is disposed at the end portion of the flow channel structure.

There are provided a substrate on which a first integrated circuit, a first transistor, and a first inductor element are disposed, and which has a first side and a second side facing each other; a heat sink having a fifth side and a sixth side along the first side; the first integrated circuit, the first transistor, and the first inductor element are positioned in order of the first integrated circuit, the first transistor, and the first inductor element from the first side toward the second side, and the heat sink is fixed to the substrate such that a shortest distance between the fifth side and the first side is shorter than a shortest distance between the sixth side and the first side, and a shortest distance between the first integrated circuit and the fifth side is longer than a shortest distance between the first transistor and the sixth side.

There are provided a first fixing section to a third fixing section that fix a heat sink to a substrate on which a first driving circuit and a second driving circuit are disposed; the first drive circuit includes first transistor and first integrated circuit, and the second drive circuit includes second transistor and second integrated circuit, lengths of the first transistor and the second transistor in the normal direction of the substrate are longer than lengths of the first integrated circuit and the second integrated circuit, the first fixing section and the second fixing section overlap a first virtual straight line that connects the first transistor and the second transistor, and the third fixing section overlaps a second virtual straight line that connects the first integrated circuit and the second integrated circuit to each other.

There is provided a head unit including: a substrate on which a first driving circuit is disposed; a heat sink fixed to the substrate; and heat conductive elastic bodies positioned between the substrate and the heat sink, in which the first driving circuit includes a first integrated circuit, a first amplifier circuit including a first transistor, and a first smoothing circuit that outputs the first driving signal, in which a first heat conductive elastic body is in contact with the heat sink and the first integrated circuit, a second heat conductive elastic body is in contact with the heat sink and the first transistor, and the first heat conductive elastic body and the second heat conductive elastic body are in a form of a gel having flame retardancy and electric insulation property.