A rebounding phenomenon of an actuator assembly is to be prevented and
device assembling work and maintenance work are to be carried out
separately from stopper removing work. In one embodiment, a magnetic disk
device includes a stopper 50 for restricting a turning range of an
actuator assembly 8 having a coil support 22 in a magnetic disk device.
In the stopper 50, rubber 51 is cantilevered by a support rod 261 so as
to undergo a moment of force and fulfill a shock absorbing function in
order to restrict an excessive movement of the actuator assembly 8 to an
inner or an outer side when the rubber 51 is abutted against a first arm
22a or a second arm 22b of a bifurcated shape of the coil support 22, the
support rod 261 is disposed outside a turning track of turning ends of
the first and second arms 22a, 22b of the coil support 22, and a
permanent magnet 52 is embedded in the rubber 51 to attract the first and
second arms 22a, 22b.