Drive motor for magnetic disks, optical disks, and magneto-optical disks
AssigneeNagano Nidec Corporation
InventorsHaruo Kitahara, Takeshi Ohshita
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AssigneeNagano Nidec Corporation
InventorsHaruo Kitahara, Takeshi Ohshita
Estimating the term…
A motor for rotating a magnetic disk, an optical disk, or a magneto-optical disk comprises an armature concentrically secured to a center shaft affixed to the base frame of a disk drive unit. A rotor frame is rotatably supported in a cantilever fashion on a free end of the center shaft by a pair of bearings. The rotor frame is cup-shaped with a depending cylindrical sidewall encircling the outer peripheral surface of the armature. The sidewall includes a disk support that projects outwardly from the sidewall. A permanent magnet secured inside the sidewall interacts with magnetic fields produced by the armature. The cantilever support makes it easier to bring armature leads through a hole in the mounting frame as a part of the manufacturing process. In an alternate embodiment, the center shaft is shortened so that the lower bearing on the shaft rests upon the frame. The cup-shaped rotor is mounted on the bearings with a hub having a depending cylindrical wall mounted on the lower bearing. The frame has an upstanding cylindrical wall encircling the depending cylindrical wall of the hub. The armature is mounted on the outer surface of the upstanding wall so that it encircles the lower bearing. This embodiment has a short axial length which produces a compact motor.
A motor, suitable for driving a magnetic disk, an optical disk, or a magneto-optical disk, which comprises:
[3. A motor according to claim 2 wherein said spring elements are Belleville springs.]
[4. A motor according to claim 1
[5. A motor according to claim 4 wherein said annular spacer is an annular ring.]
[6. A motor according to claim 5 wherein said annular ring comprises an annular segment.]
[7. A motor according to claim 5 wherein said annular ring comprises a plurality of annular segments.]
[8. A motor according to claim 4 wherein said annular spacer comprises an annular projection on the inside surface of said cup shaped rotor.]
[9. A motor according to claim 11 wherein said disk support means comprises an annular projection on the outside of said open bottom of the cup shaped rotor, and said annular projection has an upper surface in a plane perpendicular to the axis of said upstanding shaft.]
[10. A motor according to claim 9 wherein said rotor has a cylindrical outer surface above said annular projection, whereby a plurality of disks may be
[15. A motor according to claim 1 wherein said aperture is located proximate said upstanding shaft.]
[16. A motor according to claim 1 wherein said permanent magnets are disposed angularly on an inside surface of said rotor so as to present alternate north and south poles in magnetic engagement with said armature.]
[17. A motor according to claim 1 including at least one side wall in the shape of a segment of a hollow cylinder.]
[18. A motor, suitable for driving a magnetic disk, an optical disk, or a magneto-optical disk, which comprises:
[19. A motor according to claim 18 wherein said bearings are spaced apart by spring elements.]
[20. A motor according to claim 19 wherein said spring elements are Belleville springs.]
[21. A motor according to claim 18 wherein said bearings are spaced apart by an annular spacer.]
[22. A motor according to claim 21 wherein said annular spacer is an annular ring.]
[23. A motor according to claim 22 wherein said annular ring comprises an annular segment.]
[24. A motor according to claim 22 wherein said annular ring comprises a plurality of annular segments.]
[25. A motor according to claim 21 wherein said annular spacer comprises an annular projection on the inside surface of said rotor central hub.]
[26. A motor according to claim 18 wherein said cup shaped rotor includes disk support means for mounting a disk on said rotor in a plane perpendicular to the axis of said upstanding shaft.]
[27. A motor according to claim 1 wherein said aperture is located proximate said armature.]
[28. The motor of claim 1 wherein said permanent magnets are disposed angularly on the inside surface of said rotor so as to present alternate north and south poles in magnetic engagement with said
[31. The motor of claim 11 wherein said permanent magnets are disposed angularly on the inside surface of said rotor so as to present alternate north and south poles in magnetic engagement with said
A motor, suitable for driving a magnetic disk, an optical disk, or a magneto-optical disk which comprises:
Dependencies are inferred from the claim text.