Inkjet head

An inkjet head for performing printing on a printing medium by ejecting ink onto the printing medium, the inkjet head comprising:

• an ejector unit that ejects the ink in accordance with a driving signal;
• and
• a drive substrate unit that supplies the driving signal to the ejector unit,
• wherein the ejector unit includes:
• a base plate;
• an ejector that ejects the ink from an ejection outlet, the ejector being arranged in the base plate;
• and
• an ejector-side connector that receives the driving signal,
• the drive substrate unit includes:
• a drive substrate that generates the driving signal;
• a drive-substrate-side connector that outputs the driving signal;
• and
• a case that holds the drive substrate and the drive-substrate-side connector,
• the drive substrate unit is detachable from the ejector unit in an axial direction orthogonal to the base plate,
• when the case is mounted on the ejector unit, the drive-substrate-side connector and the ejector-side connector are connected to each other and at least part of the drive substrate overlaps the ejector-side connector in a horizontal direction,
• the case includes:
• four side walls that expand into a square cylinder shape in the axial direction;
• and
• a top plate that covers one end of the side wall in the axial direction, the one end being away from the base plate,
• the four side walls include:
• a pair of wide-face walls facing each other;
• and
• a pair of narrow-face walls facing each other and having a smaller surface area than the pair of wide-face walls,
• the drive substrate unit includes:
• a cooling jacket with a line arranged in a loop for circulating cooling water, the cooling jacket cooling the drive substrate by passing the cooling water through an interior of the line, the cooling jacket being arranged between the drive substrate and an inner surface of the case;
• and
• connection ports formed in the side walls and connected to both ends of the line of the cooling jacket, and
• at least part of the connection ports is located in the vicinity of the top plate, and the connection ports are provided, on only the narrow-face wall located on the one side of the pair of narrow-face walls, at intervals in the axial direction, and
• the cooling jacket is arranged apart from the ejector unit in the axial direction.