Data storage device with mechanism to control rotation of spindle motor

A data storage device comprising:

• a storage disk configured to store data;
• a fluid dynamic bearing motor configured to rotate the storage disk, said fluid dynamic bearing motor comprising a stator for producing a rotating magnetic force, and a rotor that rotates in response to the rotating magnetic force applied by the stator, said rotor having a magnet unit;
• and
• a base that receives the fluid dynamic bearing motor, and that is formed of a magnetic material, said base having a convex part at a position facing the magnet unit, the convex part being spaced from the magnet unit by a gap which is unoccupied and adjusted to control a magnetic back pressure generated between the convex part of the magnetic base and the magnet unit so as to control floating of the rotor, the convex part being an integrally formed part of the base that is made of the magnetic material, the base having a corresponding concave part on a surface opposite from the convex part.

A data storage device comprising:

• a storage disk configured to store data;
• a fluid dynamic bearing motor configured to rotate the storage disk;
• and
• a base configured to receive the fluid dynamic bearing motor;
• wherein the fluid dynamic bearing motor comprises a stator that is secured to the base;
• and a rotor that rotates in response to a rotating magnetic force applied by the stator, said rotor having a magnet unit;
• wherein the base is made of a magnetic material and has a convex part that is formed at a position facing the magnet unit, the convex part being an integrally formed part of the base that is made of the magnetic material, the convex part protruding toward the magnet unit, the convex part being spaced from the magnet unit by a gap which is unoccupied and adjusted to control a magnetic back pressure generated between the convex part of the magnetic base and the magnet unit, the base having a corresponding concave part on a surface opposite from the convex part;
• wherein the rotor comprises a hub to which the storage disk is secured, and in which a concave part is formed on a surface facing the bottom of the base;
• and a magnet unit that is secured to the hub;
• and
• wherein a hub-side end of the magnet unit is received in the concave part of the hub.

A data storage device comprising:

• a storage disk configured to store data;
• a fluid dynamic bearing motor configured to rotate the storage disk;
• and
• a base configured to receive the fluid dynamic bearing motor;
• wherein the fluid dynamic bearing motor comprises a stator that is secured to the base;
• and a rotor that rotates in response to a rotating magnetic force applied by the stator, said rotor having a magnet unit;
• and
• wherein the base is made of a magnetic material and has a plurality of convex parts that are formed at positions facing the magnet unit, the convex parts protruding toward the magnet unit, the convex parts being spaced from the magnet unit by gaps which are unoccupied and adjusted to control a magnetic back pressure generated between the convex parts of the magnetic base and the magnet unit.