Minimizing flow induced vibration in a hard disk drive with a hybrid planar plate having a bypass channel

A hard disk drive comprising:

• a base casting for providing coupling points for components and subassemblies of said hard disk drive;
• a motor-hub assembly to which at least one disk is coupled allowing rotation of said disk about an axis approximately perpendicular and centered to said disk, wherein said motor-hub assembly is coupled to said base casting, wherein said disk comprises at least one surface of data tracks;
• and
• an airflow control device comprising:
• an outer perimeter defined by a length having a radius equal to or greater than an outer radius of a disk in said hard disk drive;
• a thickness less than a spacing between adjacent disks in said hard disk drive;
• a central opening having an inner perimeter surface with a radius greater than an outer radius of a spacer ring of said hard disk drive;
• a notch in said outer perimeter, wherein said notch is configured to accommodate an actuator assembly of said hard disk drive;
• and
• a bypass slot transecting said outer perimeter, wherein said bypass slot has a bend with a radius nearly centered to said central opening and wherein said bypass slot comprises two surfaces along said length of said bypass slot, said length more than half of said outer perimeter, one of said two surfaces is discontinuous and said two surfaces are separated by a distance that varies, said bypass slot forming a first opening for receiving said airflow and a second opening for exiting said airflow, wherein at least said first opening or said second opening is integral with said base casting.

A method of reducing airflow induced vibration in a hard disk drive, said method comprising:

• providing a planar surface having an outer perimeter and defined by a length and configured to fit between adjacent disk surfaces in a hard disk drive;
• interleaving said planar surface between said adjacent disk surfaces, wherein a bypass channel is formed between a bypass slot within said planar surface and said surface of said disk such that said bypass slot comprises two surfaces along said length of said bypass slot, said length more than half of said outer perimeter of said planar surface, one of said two surfaces is discontinuous and said two surfaces are separated by a distance that varies;
• presenting a first distal opening of said bypass channel such that upon rotation of said disk, air enters said bypass channel at a location near an outer wall of said hard disk drive, and away from an actuator of said hard disk drive;
• and
• presenting a second distal opening of said bypass channel to an outer wall of said hard disk drive such that said air exiting said bypass channel is directed away from a voice coil motor of said hard disk drive, thereby enabling laminar flow of said airflow upon rotation of said disk and reducing airflow induced vibration in said hard disk drive, wherein at least said first distal opening or said second distal opening is integral with a base casting of said hard drive.