A hinge unit includes a first member, a second member, a coupling member, a protrusion fixed to the first member, and a tilt stopper. When the tilt stopper is fixed at a position (P1) of the second member, the tilt stopper and the protrusion are brought into contact with each other, to thereby limit a movable range within a first angle range. When the tilt stopper is fixed at a position (P2) of the second member, the tilt stopper and the protrusion are held in non-contact with each other irrespective of a pivoting angle.