A liquid ejecting apparatus includes a head that includes an ejecting portion that, upon receiving a drive signal, ejects liquid; a controller that performs control on circulation of liquid through the first flow passage, wherein the controller performs first control of circulating liquid through the first thermal conductive member and the second thermal conductive member in this order in the first flow passage when an amount of heat generated at the first portion is larger than an amount of heat generated at the second portion, and performs second control of circulating liquid through the second thermal conductive member and the first thermal conductive member in this order in the first flow passage when an amount of heat generated at the second portion is larger than an amount of heat generated at the first portion.

An inkjet printer that includes an inkjet head in which a plurality of ink flow paths are formed is provided. In this inkjet printer, a plurality of nozzles from which ink is ejected and a plurality of ink flow paths to which the plurality of nozzles are connected are formed in an inkjet head. The inkjet head includes a plurality of ejection energy generation elements that make the plurality of respective nozzles eject ink. Based on an ink flow rate which is a flow rate of ink flowing into each of the plurality of ink flow paths and internal temperature or external temperature of the inkjet head, a controller of the inkjet printer estimates the ink temperature in each of the plurality of ink flow paths, and controls drive voltage applied to the plurality of ejection energy generation elements based on the result of the estimation.

There is provided a liquid discharge apparatus, in which a substrate unit includes a first drive circuit that has a first coil, a second drive circuit that has a second coil, a cooling fan that generates an air flow, a wiring substrate having a plurality of rigid members and a flexible member, and a plate-shaped opening member having a first opening and a second opening, the cooling fan generates an air flow in a space where a first front surface of a first rigid member on which the first coil is provided and a second front surface of a second rigid member on which the second coil is provided, and when viewed along a normal direction of the opening member, the first opening overlaps with at least a part of the first coil, and the second opening overlaps with at least a part of the second coil.

A drive unit is configured to generate a drive signal for driving a liquid ejecting head unit. The drive unit includes a drive board on which a drive circuit configured to generate the drive signal is mounted; a thermal conductive material that is in contact with the drive circuit on an opposite side in relation to the drive board; a water cooling mechanism that is in contact with the thermal conductive material on an opposite side in relation to the drive circuit; a pump that causes liquid in the water cooling mechanism to flow; and a control circuit that controls operation of the pump. The control circuit switches a direction in which the pump causes the liquid to flow between a forward direction and a reverse direction that is an opposite of the forward direction.

The image forming apparatus includes an ejection portion, a guide portion, a plurality of heating elements, a determination processing portion, and a drive control portion. The ejection portion ejects ink toward a first surface of a strip-shaped medium. The guide portion is provided at a position sandwiching the medium between the guide portion and the ejection portion, and forms a guide surface that guides the medium by coming into contact with a second surface on a rear side of the first surface of the medium. The plurality of heating elements are arranged along a width direction of the medium below the guide surface. The determination processing portion determines the heating elements to be driven based on the width of the medium. The drive control portion drives the heating elements determined by the determination processing portion as heating elements to be driven.

A cooling efficiency is increased. An inkjet head is provided with a head main body for jetting ink, a cooling pipe which has corrosion resistance to the ink, and through which the ink for cooling a drive circuit passes, and a cooling member which has higher thermal conductivity than that of the cooling pipe, in which at least a part of the cooling pipe is embedded, and which has recessed parts in at least a part of a portion surrounding the cooling pipe.