Optimum Design of Oil Lubricated Thrust Bearing for Hard Disk Drive with High Speed Spindle Motor

Table 1

Initial 2.5 inch bearing parameters.

Parameters	Values
Outer radius 𝑅out (m)	2.55×10^−3
Inner radius 𝑅in (m)	1.0×10^−3
Weight 𝑊𝑑 (N)	0.185
Revolution speed 𝑛𝑠 (rpm)	5000~20,000
Groove number 𝑁	16
Seal ratio 𝑟𝑠	0.58
Groove depth ℎ𝑔 (m)	1.0×10^−5
Groove width ratio 𝛼=(𝑏1/𝑏1+𝑏2)	0.5
Geometry parameter 𝜑1 (deg)	0.0
Geometry parameter 𝜑2 (deg)	0.0
Geometry parameter 𝜑3 (deg)	0.0
Geometry parameter 𝜑4 (deg)	0.0
Lubricant viscosity 𝜇 (Pa·s)	6.523×10^−3