Patent ID: 7016146

Claim:
A spindle motor for use in a disk drive comprising: a shaft having a larger diameter section and a smaller diameter section with a step formed therebetween; a bearing sleeve having a central cylindrical opening, said shaft being inserted into said central cylindrical opening; a bearing gap formed between said shaft and said bearing sleeve, said bearing gap being filled with lubricating fluid; and a counter plate sealing said central cylindrical opening of said bearing sleeve, said counter plate being in an opposing relationship with said step; wherein a first hydrodynamic thrust bearing is formed between said step and said counter plate, wherein a hydrodynamic radial bearing is formed in the area of said larger diameter section of said shaft, wherein one end of said shaft is enclosed by said bearing sleeve, and wherein a second hydrodynamic thrust bearing is formed at said enclosed end of said shaft, such that said hydrodynamic radial bearing is located between said first hydrodynamic thrust bearing and said second hydrodynamic thrust bearing.