A disk player is configured so that a steel plate-made clamper plate 3 is
bridged between wall parts 2a of both sides of a cabinet and is fixed and
a disk D on a tray 1 is clamped by a turntable 7 and a clamper 5 and the
disk D is rotated by the turntable 7 and information recorded on the disk
D is read by an optical pickup, spiral reinforcement portions 3c are
formed by closely folding both side edges of the clamper plate 3 in a
manner of winding at least two times.