US 7,576,936 B2
Method of starting the magnetic disk device using fluid dynamic bearing spindle motor
Iwao Oshimi, Kanagawa (Japan); Gaku Ikedo, Kanagawa (Japan); Nobuhisa Koide, Kanagawa (Japan); and Jiro Abe, Kanagawa (Japan)
Assigned to Hitachi Global Storage Technologies Netherlands B.V., Amsterdam (Netherlands)
Filed on Sep. 07, 2007, as Appl. No. 11/899,767.
Claims priority of application No. 2006-243201 (JP), filed on Sep. 07, 2006.
Prior Publication US 2008/0062555 A1, Mar. 13, 2008
Int. Cl. G11B 15/46 (2006.01); G11B 15/18 (2006.01)
U.S. Cl. 360—73.03  [360/69] 16 Claims
OG exemplary drawing
 
1. A magnetic disk device, comprising:
a spindle motor using a fluid dynamic bearing;
an rpm detecting unit detecting rpm of the spindle motor; and
a temperature measuring unit measuring an ambient temperature for the magnetic disk device, characterized in that upon starting the magnetic disk device, a waiting time preset in accordance with the ambient temperature measured with the temperature measuring unit is inserted to a period from when the spindle motor reaches a rated speed until when an indication of an ability of the magnetic disk device to enter a useable state is sent back to a host from the magnetic disk device, the magnetic disk device further comprising a voltage measuring unit measuring a voltage applied to the magnetic disk device, characterized in that a waiting time preset in accordance with a combination between the ambient temperature measured with the temperature measuring unit and the voltage measured with the voltage measuring unit is inserted.