Magnetic disk drive and magnetic disk drive system

Abstract

A magnetic disk drive that shape coefficient is 3.5 inches are provided, which is designed as rotating magnetic media in a high speed in order to consume a low electric power, to generate a less heat, and to access more quickly. When magnetic disk media are rotated in a higher speed, an electric power consumption and a heat generation are increased because of a load increase in rotating the magnetic disk media. An avoidance of such problems and setting an additional special cooling mechanism to magnetic disk drive systems, for example, disk array systems, is presented. A housing 11 of magnetic disk drive in a shape coefficient 3.5 inches mounts magnetic disk media 21 for a magnetic disk drive in a shape coefficient 2.5 inches, which aims a lightweighting of a rotational spindle portion, a decrease of a torque loss during on-load rotation with the media, and a decrease of a electric current into a spindle motor 41 during rotation. Further, fins 11 a for heat radiation may be arranged around the housing 11, which results in avoidance or decrease raising a temperature in the housing 11.

We claim:  
     
         1 . A magnetic disk drive, comprising: 
 magnetic disk media recording information;    a hub holding said magnetic disk media rotatablly;    a spindle motor rotating said hub;    a magnetic head recording or reproducing information to or from said magnetic disk media;    an actuator holding and locating said magnetic head at a predetermined position on said magnetic disk media; and    a housing in a shape of 3.5 inches form factor size, mounting said magnetic disk media, said hub, said magnetic head and said actuator;    wherein said magnetic disk media held on said hub, are smaller in diameter than magnetic disk media those are used for 3.5 inches form factor magnetic disk drive.    
     
     
         2 . A magnetic disk drive according to  claim 1 , wherein said spindle motor rotates 10000 rpm or more.  
     
     
         3 . A magnetic disk drive according to  claim 2 , further comprising fins arranged around said magnetic disk media.  
     
     
         4 . A magnetic disk drive, comprising: 
 magnetic disk media recording information;    a hub holding said magnetic disk media rotatablly;    a spindle motor rotating said hub;    a magnetic head recording or reproducing information to or from said magnetic disk media;    an actuator holding and locating said magnetic head at a predetermined position on said magnetic disk media; and    a housing in a shape of 3.5 inches form factor size, mounting said magnetic disk media, said hub, said magnetic head and said actuator;    wherein said magnetic disk media held on said hub, are not greater in diameter than shape-coefficient 2.5 inches' magnetic disk media.    
     
     
         5 . A magnetic disk drive according to  claim 4 , wherein said spindle motor rotates 10000 rpm or more.  
     
     
         6 . A magnetic disk drive according to  claim 1 , wherein said hub and said actuator are arranged so that a distance between a rotation center of said hub and a swing center of said actuator is at most 40 milli meters ±1 milli meters.  
     
     
         7 . A magnetic disk drive according to  claim 1 , wherein said hub and said actuator are arranged so that a distance between a rotation center of said hub and a swing center of said actuator is between 40 milli meters and 47.5 milli meters.  
     
     
         8 . A magnetic disk drive according to  claim 6  or  claim 7 , wherein an average access time in locating said magnetic head to said predetermined position on said magnetic disk media, is not greater than 7.5 milli seconds when a torque of said actuator is at least 0.12 Newton.meter per one ampere current.  
     
     
         9 . A magnetic disk drive according to  claim 6  or  claim 7 , wherein an average access time in locating said magnetic head to said predetermined position on said magnetic disk media, is not greater than 7.5 milli seconds when a weight of rotational portion at said actuator is not greater than 36 gram.force.  
     
     
         10 . A magnetic disk drive according to  claim 4  further comprising fins arranged around said magnetic disk media.  
     
     
         11 . A magnetic disk drive according to  claim 3  or  claim 10 , wherein said fin is a member having unlevel, washboard or jaggy portion in cross sectional view which is given if said fin is cut by a plane along a rotational axis of said hub.  
     
     
         12 . A magnetic disk drive according to  claim 3  or  claim 10 , wherein said fin is casted en bloc with said housing.  
     
     
         13 . A magnetic disk drive system, comprising: 
 a case mounting and securing a plurality of magnetic disk drive according to claim  2 ; and    a control unit coupling and controling said magnetic disk drives electrically.    
     
     
         14 . A magnetic disk drive system, comprising: 
 a case mounting and securing a plurality of magnetic disk drive according to claim  3 ; and    a control unit coupling and controling said magnetic disk drives electrically.    
     
     
         15 . A magnetic disk drive system according to  claim 13  or  claim 14 , further comprising a fan cooling said plurality of magnetic disk drive or said control unit.  
     
     
         16 . A magnetic disk drive according to  claim 4 , further comprising fins arranged around said magnetic disk media along a depth direction or a width direction of the magnetic disk drive.  
     
     
         17 . A magnetic disk drive according to  claim 16 , wherein fins arranged along said depth direction exclusively or along said width direction, have plural rows arranged one another at different positions in the thickness direction of the magnetic disk drive.  
     
     
         18 . A magnetic disk drive according to  claim 16 , wherein remain fins arranged along said width direction exclusively or along said depth direction, have one row or two rows.  
     
     
         19 . A magnetic disk drive according to  claim 3  further comprising a fan making an air flow in a depth direction or a width direction of the magnetic disk drive.  
     
     
         20 . A magnetic disk drive according to  claim 10 , wherein said housing has a hole to record a servo signal to said magnetic disk media.  
     
     
         21 . A magnetic disk drive system, comprising: 
 a case mounting and securing a plurality of magnetic disk drive according to  claim 4 ,  claim 10 , or claim  19 ; and    a control unit coupling and controling said magnetic disk drives electrically.