Equalization and minimization of multi-head stack assembly's motion during self servo writing and HDD operation
View Patent ↗A disk hard disk drive that includes a spindle motor and an actuator arm coupled to a base plate. A plurality of disks are coupled to the spindle motor and a plurality of heads are coupled to the actuator arm and the disks. The drive also includes a cover attached to the base plate. The cover and base plate enclose a hard disk area that has a horizontal center line. The hard disk area includes a volume of air above the horizontal center line that is equal to a volume of air below the horizontal center line. The air space within the hard disk area is equal and symmetrical in a vertical direction. Such an arrangement reduces track mis-registration when servo is copied from a disk surface to the other surfaces of the disks in the drive.
1. A hard disk drive, comprising:
a base plate;
a spindle motor coupled to said base plate;
a plurality of disks coupled to said spindle motor;
an actuator arm mounted to said base plate;
a voice coil motor coupled to said actuator arm;
a plurality of heads coupled to said actuator arm and said disks; and,
a cover attached to said base plate, said cover and said base plate enclose a hard disk area having a horizontal center line, said hard disk area includes a volume of air above said horizontal center line that is equal to a volume of air below said horizontal center line.
2. The hard disk drive of claim 1 , wherein there are an equal number of disks above and below said horizontal center line.
3. The hard disk drive of claim 2 , wherein there are an equal number of heads above and below said horizontal center line.
4. The hard disk drive of claim 1 , further comprising a circuit that causes a writing of servo on at least one disk surface.
5. A method for copying servo onto at least one disk of a hard disk drive, comprising:
providing a hard disk drive including;
a base plate;
a spindle motor coupled to said base plate;
a plurality of disks coupled to said spindle motor, at least one of said disks having servo information;
an actuator arm mounted to said base plate;
a voice coil motor coupled to said actuator arm;
a plurality of heads coupled to said actuator arm and said disks;
a cover attached to said base plate, said cover and said base plate enclose a hard disk area having a horizontal center line, said hard disk area includes a volume of air above said horizontal center line that is equal to a volume of air below said horizontal center line; and,
copying the servo information onto at least one other disk of the hard disk drive.
6. The method of claim 5 , wherein there are an equal number of disks above and below the horizontal center line.
7. The method of claim 6 , wherein there are an equal number of heads above and below the horizontal center line.