. . "FIGS. 20A, 20B and 20C are diagrams illustrating the structure and operation of the second loading arm, in which FIG. 20A is a plan view of the guide arm and retention arm in a disassembled state, FIG. 20B is a plan view of the second loading arm in a state in which the disk is loaded, and FIG. 20C is a plan view of the second loading arm in a state in which the disk is ejected." . .