Head Unit And Liquid Ejecting Apparatus

A head unit comprising:

• a first liquid ejecting head configured to eject liquid in a first direction;
• and
• a support member that supports the first liquid ejecting head, wherein
• the support member includes
• a support plate having a first surface that supports the first liquid ejecting head and faces the first direction, and
• a first positioning portion for positioning the first liquid ejecting head with respect to the support plate,
• the first liquid ejecting head includes
• a plurality of head chips having a plurality of nozzle groups,
• a cover member in which a plurality of exposure opening portions for exposing each of the plurality of nozzle groups to an outside are formed and to which the plurality of head chips are fixed,
• a base member to which the cover member is fixed, and
• a multilayer structure that includes a plurality of stacked substrates stacked in the first direction and is stacked in a second direction opposite to the first direction on a mounting surface provided on the base member,
• the multilayer structure includes a facing portion facing the first surface,
• the base member includes a protruding portion protruding from the mounting surface in the second direction, and
• the protruding portion includes
• a contact surface in contact with the first surface, and
• a second positioning portion that is provided so as to correspond to the first positioning portion and positions the first liquid ejecting head with respect to the support plate.