HARD DISK DRIVE

1 . A hard disk drive comprising:

an end tap which extends from an end part of a suspension which supports a slider;

a ramp which comprises a parking guide rail including a parking guide wall on which the end tap is contact-guided and parked when a disk stops rotating; and

a ramp rotating unit which is connected to the ramp and rotates the ramp based on parking states of the end tap.

2 . The hard disk drive according to claim 1 , wherein the parking guide wall comprises:

a normal parking guide section on which the end tap is contact-guided when the end tap is parked during a normal parking; and

an emergency parking guide section, adjacent to the normal parking guide section, on which the end tap is contact-guided when the end tap is parked during an emergency parking,

wherein the ramp rotating unit rotates the ramp so that the end tap is contact-guided and parked on the emergency parking guide section when the end tap is parked during the emergency parking.

3 . The hard disk drive according to claim 1 , wherein the ramp rotating unit comprises

a rotation shaft coupled to one side of the ramp and forming a rotation axis of the ramp; and

a rotational force transmitter connected to the ramp and transmitting rotational force to rotate the ramp with respect to the rotation shaft.

4 . The hard disk drive according to claim 3 , wherein the rotational force transmitter comprises:

a shape memory device which is in contact with the ramp and rotates the ramp with respect to the rotation shaft by pressing on the ramp due to a change in shape of the shape memory device; and

a power supply which supplies an electric current to the shape memory device based on the parking states of the end tap to change the shape of the shape memory device.

5 . The hard disk drive according to claim 4 , wherein the shape memory device comprises a shape memory polymer which recovers an original state when the electric current is cut off from the power supply.

6 . The hard disk drive according to claim 1 , wherein the ramp is rotatable by the ramp rotating unit through an angle of approximately 5 degrees to 15 degrees.

7 . The hard disk drive according to claim 1 , wherein the parking guide rail comprises a front end having a first section which is perpendicular to a length of the parking guide rail and a second section which is inclined with respect to the length of the parking guide rail.

8 . The hard disk drive according to claim 2 , wherein the emergency parking guide section comprises a wave surface more waved than a surface of the normal parking guide.

9 . The hard disk drive according to claim 2 , wherein the emergency parking guide section is higher than the normal parking guide section.

10 . The hard disk drive according to claim 2 , wherein a surface roughness of the emergency parking guide section is different from a surface roughness of the normal parking guide section.

11 . A method of operating a hard disk drive including a rotatable actuator arm having an end tap extending therefrom and a rotatable ramp, the method comprising:

during a driving state, positioning the actuator arm in a position over a disk; and

during a normal parking state:

rotating the actuator arm toward the ramp, and

rotating the ramp into a normal parking state position; and

during an emergency parking state,

rotating the actuator arm toward the ramp, and

rotating the ramp into an emergency parking position, different from the normal parking state position.

12 . The method according to claim 11 , wherein:

rotating the actuator arm toward the ramp and rotating the ramp into the normal parking position comprises bringing the end tap into contact with a normal parking guide section of the ramp; and

rotating the actuator arm toward the ramp and rotating the ramp into the emergency parking position comprises bringing the end tap into contact with an emergency parking guide section of the ramp.

13 . The method according to claim 12 , wherein:

the normal parking guide section is shorter than the emergency parking guide section.

14 . The method according to claim 12 , wherein:

the normal parking guide section is more planar than the emergency parking guide section.

15 . The method according to claim 12 , wherein:

the emergency parking guide section is rougher than the normal parking guide section.