Axially compact direct drive for storage disk hub

Abstract

An axial compact direct drive for a storage disk comprises a stator, a rotor carrying a hub for receiving storage disks and a bearing arrangement. The bearing arrangement is disposed at a radially external edge of the hub to rotatably support the hub against axial and radial movement. The rotor is electrically driven at locations in the center of the stator or at locations surrounding the stator.

We claim:  
     
       1. A storage disk drive, especially for a hard storage disk, comprising a stator, a rotor, a bearing arrangement ( 10 ,  12 ;  18 ,  19 ) and a coaxial hub ( 5 ,  7 ) having a radially external edge, to the outer surface of which one or more hard disks are secured, characterised in that the bearing arrangement rotatably supports the hub ( 5 ,  7 ) exclusively in the region of the radially external edge of the hub. 
     
     
       2. A storage disk drive according to claim  1 , characterised in that the bearing arrangement radially surrounds, the stator and the rotor. 
     
     
       3. A storage disk drive according to claim  1  or claim  2 , characterised in that the hub ( 5 ,  7 ) is substantially cup-shaped, and that an outer race of at least one ball bearing ( 10 ,  18 ,  19 ) is secured to a cylindrical inner wall ( 11 ,  24 ) of the hub ( 5 ). 
     
     
       4. A storage disk drive according to claim  1  or claim  2 , characterised in that an outer surface ( 7 ) of the hub ( 5 ) passes over radially into a flange-like outwardly projecting support ( 14 ), an inner ring of at least one ball bearing ( 12 ) being arranged on a hollow cylindrical ring part ( 17 ) on the other axial side of the hub. 
     
     
       5. A storage disk drive according to claim  1  or claim  2 , characterised in that the rotor, stator, hub and bearing arrangement are concentric and engaged radially with one another. 
     
     
       6. A storage disk drive according to claim  1  or claim  2 , characterised in that the bearing arrangement comprises at least one roller bearing ( 10 ,  12 ). 
     
     
       7. A storage disk drive according to claim  1  or claim  2 , characterised in that the rotor comprises hollow cylindrical permanent magnetic rotor magnets ( 3 ,  4 ) having an additional soft magnetic return ring on the surface ( 33 ,  34 ) at the rear side of an air gap between the rotor and the stator. 
     
     
       8. A storage disk drive according to claim  1  or claim  2 , characterised in that the rotor comprises hollow cylindrical permanent magnetic rotor magnets ( 3 ,  4 ) having a soft magnetic return ring formed by a hollow cylindrical ring part  17  consisting of a ferromagnetic material on the surface ( 33 ,  34 ) at the rear side of an air gap between the rotor and the stator. 
     
     
       9. A storage disk drive according to claim  8 , characterised in that the hollow cylindrical ring part  17  is integrally moulded with the hub ( 5 ). 
     
     
       10. A storage disk drive according to claim  8 , characterised in that the hollow cylindrical ring part  17  is coaxially connected to the hub ( 5 ) as a separate component. 
     
     
       11. A storage disk drive according to claim  1  or claim  2 , characterised in that the bearing arrangement comprises an integrated ball bearing comprising an in-wrought ball race ( 122 ) on the rotor side. 
     
     
       12. A storage disk drive according to claim  1  or claim  2 , wherein said bearing arrangement comprises a ball cage device ( 73 ) which serves simultaneously as a sealing element. 
     
     
       13. A storage disk drive according to any one of the preceding claims, characterised in that a ventilation device is provided, consisting of an inlet opening ( 71 ) and an outlet opening ( 72 ), the openings ( 71 ) and ( 72 ) being provided with filter inserts. 
     
     
       14. A storage disk drive according to any one of the preceding claims, characterised in that an exchangeable stator part ( 1 ) is provided for subsequent mounting in the storage disk drive. 
     
     
       15. A storage disk drive, especially for a hard storage disk, comprising a stator, a rotor, a bearing arrangement ( 10 ,  12 ;  18 ,  19 ) and a coaxial hub ( 5 ,  7 ) having a radially external edge, to the outer surface of which one or more hard disks are secured, characterised in that the bearing arrangement comprises a bearing disposed in the region of the radially external edge of the hub which rotatably supports the hub against axial and radial movement. 
     
     
       16. A disk storage device comprising: 
       
         a clean room;  
       
       
         at least one data storage disk;  
       
       
         a data read head for movement in operative relation to the disk within the clean room;  
       
       
         a rotatable disk mounting element forming a hub for supporting said storage disk in said clean room, said disk mounting element having a radially external edge;  
       
       
         a permanent magnetic ring affixed to said rotatable disk mounting element, said ring having an outer diameter of a first dimension;  
       
       
         a stator positioned within said permanent magnetic ring and separated therefrom by a substantially cylindrical air gap, said stator producing magnetic flux interacting with said permanent magnetic ring to rotate said rotatable disk mounting element and said data storage disk;  
       
       
         a base plate defining a portion of the clean room, said base plate including a bearing support element defining a circular bearing path having a diameter greater than said first dimension; and  
       
       
         bearing means engaging said bearing support element and said rotatable disk mounting element for rotatably supporting the disk mounting element on said base plate exclusively in the region of the radially external edge of said disk mounting element.  
       
     
     
       17. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one hard storage disk;  
       
       
         a data read head for movement in operative relation to the disk within the clean room;  
       
       
         a stator;  
       
       
         a cylindrical rotor member having an outer diameter of first dimension;  
       
       
         a coaxial hub having a radially external edge, to the outer surface of which said hard disk is secured; and  
       
       
         a bearing arrangement mounted on said base plate including bearing elements rotatably supporting said coaxial hub exclusively in the region of the radially external edge of said coaxial hub, said bearing elements being restrained to follow a circular bearing path having a diameter greater than said first dimension.  
       
     
     
       18. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read head for movement in operative relation to the disk within the clean room;  
       
       
         a rotatable disk mounting element forming a hub for supporting said storage disk in said clean room, said disk mounting element having a radially external edge;  
       
       
         a cylindrical bearing support member mounted on said base plate;  
       
       
         at least one bearing mounted on the outer surface of said bearing support member and engaging said disk mounting element for supporting the disk mounting element exclusively in the region of the radially external edge for rotation in the clean room; and  
       
       
         a motor coupled to said disk mounting element for rotating said disk mounting element and said storage disk, said motor including stator and magnetic rotor elements mounted within said bearing support member.  
       
     
     
       19. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read head for movement in operative relation to the disk within the clean room;  
       
       
         a rotatable disk mounting element forming a hub for supporting said storage disk in said clean room, said rotatable disk mounting element having a radially external edge;  
       
       
         a cylindrical bearing support member affixed to said rotatable disk mounting element;  
       
       
         at least one bearing mounted on the outer surface of said bearing support member and engaging said base plate for supporting said disk mounting element exclusively in the region of the radially external edge for rotation in the clean room; and  
       
       
         a motor coupled to said disk mounting element for rotating said disk mounting element and said storage disk, said motor including stator and magnetic rotor elements mounted within said bearing support member.  
       
     
     
       20. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read for movement in operative relation to the disk within the clean room;  
       
       
         a stator mounted on said base plate;  
       
       
         a hub supporting said data storage disk, said hub having affixed to an inner surface thereof a magnetic element positioned to surround said stator for magnetically interacting therewith to rotate said hub, said hub having a radially external edge; and  
       
       
         a bearing arrangement rotatably supporting said hub on said base plate exclusively in the region of the radially external edge of the hub, said bearing arrangement including a plurality of bearing elements and a cage device affixed to said hub for separating said bearing elements, said cage device further arranged to provide a sealing action between said hub and said base plate.  
       
     
     
       21. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read head mounted on the base plate for movement in operative relation to the disk within the clean room;  
       
       
         a stator mounted on said base plate;  
       
       
         a hub supporting said data storage disk, said hub having affixed to an inner surface thereof a magnetic element positioned to surround said stator for magnetically interacting therewith to rotate said hub, said hub having a radially external edge;  
       
       
         a bearing arrangement rotatably supporting said hub on said base plate exclusively in the region of the radially external edge of the hub; and  
       
       
         a ventilation arrangement including an inlet opening in said base plate adjacent said stator and an outlet opening in said base plate outside the periphery of said hub, whereby rotation of said hub draws air into said inlet opening and ejects air through said outlet opening so that contaminants from said motor are removed by the flow of air through said outlet opening.  
       
     
     
       22. The drive motor of claim  21 , further comprising an air filter mounted in said inlet opening.  
     
     
       23. A disk storage device comprising: 
       
         a clean room;  
       
       
         at least one data storage disk;  
       
       
         a data head for movement in operative relation to the disk within the clean room;  
       
       
         a rotatable disk mounting element forming a hub for supporting said storage disk in said clean room, said disk mounting element having a radially external edge;  
       
       
         a permanent magnetic ring affixed to said rotatable disk mounting element, said ring having an outer diameter of a first dimension;  
       
       
         a stator positioned within said permanent magnetic ring and separated therefrom by a substantially cylindrical air gap, said stator producing magnetic flux interacting with said permanent magnetic ring to rotate said rotatable disk mounting element and said data storage disk;  
       
       
         a base plate defining a portion of the clean room, said base plate including a bearing support element defining a circular bearing path having a diameter greater than said first dimension; and  
       
       
         bearing means engaging said bearing support element and said rotatable disk mounting element for rotatably supporting the disk mounting element in the region of the radially external edge against axial and radial movement on said base plate.  
       
     
     
       24. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one hard storage disk;  
       
       
         a data read for movement in operative relation to the disk within the clean room;  
       
       
         a stator;  
       
       
         a cylindrical rotor member having an outer diameter of first dimension;  
       
       
         a coaxial hub having a radially external edge, to the outer surface of which said hard disk is secured; and  
       
       
         a bearing arrangement mounted on said base plate including bearing elements rotatably supporting said coaxial hub in the region of the radially external edge against axial and radial movement, said bearing elements being restrained to follow a circular bearing path having a diameter greater than said first dimension.  
       
     
     
       25. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read head for movement in operative relation to the disk within the clean room;  
       
       
         a rotatable disk mounting element forming a hub for supporting said storage disk in said clean room, said disk mounting element having a radially external edge;  
       
       
         a cylindrical bearing support member mounted on said base plate;  
       
       
         at least one bearing mounted on the outer surface of said bearing support member and engaging said disk mounting element to support the disk mounting element in the region of the radially external edge for rotation against axial and radial movement in the clean room; and  
       
       
         a motor coupled to said disk mounting element for rotating said disk mounting element and said storage disk, said motor including stator and magnetic rotor elements mounted within said bearing support member.  
       
     
     
       26. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read for movement in operative relation to the disk within the clean room;  
       
       
         a rotatable disk mounting element forming a hub for supporting said storage disk in said clean room, said disk mounting element having a radially external edge;  
       
       
         a cylindrical bearing support member affixed to said rotatable disk mounting element;  
       
       
         at least one bearing mounted on the outer surface of said bearing support member and engaging said base plate for supporting said disk mounting element in the region of the radially external edge for rotation against axial and radial movement in the clean room; and  
       
       
         a motor coupled to said disk mounting element for rotating said disk mounting element and said storage disk, said motor including stator and magnetic rotor elements mounted within said bearing support member.  
       
     
     
       27. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read for movement in operative relation to the disk within the clean room;  
       
       
         a stator mounted on said base plate;  
       
       
         a hub supporting said data storage disk, said hub having affixed to an inner surface thereof a magnetic element positioned to surround said stator for magnetically interacting therewith to rotate said hub, said hub having a radially external edge; and  
       
       
         a bearing arrangement rotatably supporting said hub in the region of the radially external edge against axial and radial movement on said base plate, said bearing arrangement including a plurality of bearing elements and a cage device affixed to said hub for separating said bearing elements, said cage device further arranged to provide a sealing action between said hub and said base plate.  
       
     
     
       28. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         at least one data storage disk;  
       
       
         a data read head mounted on the base plate for movement in operative relation to the disk within the clean room;  
       
       
         a stator mounted on said base plate;  
       
       
         a hub supporting said data storage disk, said hub having affixed to an inner surface thereof a magnetic element positioned to surround said stator for magnetically interacting therewith to rotate said hub, said hub having a radially external edge;  
       
       
         a bearing arrangement rotatably supporting said hub in the region of the radially external edge against axial and radial movement on said base plate; and  
       
       
         a ventilation arrangement including an inlet opening in said base plate adjacent said stator and an outlet opening in said base plate outside the periphery of said hub, whereby rotation of said hub draws air into said inlet opening and ejects air through said outlet opening so that contaminants from said motor are removed by the flow of air through said outlet opening.  
       
     
     
       29. The drive motor of claim  28 , further comprising an air filter mounted in said inlet opening.  
     
     
       30. A disk storage device comprising: 
       
         a clean room defined in part by a base plate;  
       
       
         one or more hard data storage disks;  
       
       
         a data read head mounted on the base plate for movement in operative relation to the disk within the clean room;  
       
       
         a stator;  
       
       
         a rotor;  
       
       
         a bearing arrangement and a coaxial hub having a radially external edge, to the outer surface of which the one or more hard disks are secured, characterized in that the bearing arrangement comprises a bearing disposed in the region of the radially external edge of the hub which rotatably supports the hub against axial and radial movement.