Disclosed is an inertia latch mechanism capable of omitting erection of a
pin for swinging an inertia lever. An inertia lever for use in the
inertia latch mechanism is constituted of: a lever body swinging by
inertia when an impact is applied thereto; a fixture fixed to a case of a
disk drive device; and a plate spring member for connecting the lever
body and the fixture and permitting swing of the lever body.