Inventor · Hitachi, JP

Katsutoshi Nii

37Patents
13h-index
68Co-inventors
84Inventor score

Filing activity: Oct 4, 1978 → Dec 22, 2006

Most-cited inventions

PatentTitleAreaCited byStatus
US4938611A Bearing apparatus Mechanical Engineering; Lighting; Heating 31 Expired
US5325006A Sealed magnetic fluid bearing for polygon mirror drive motor Mechanical Engineering; Lighting; Heating 28 Expired
US5834870A Oil impregnated porous bearing units and motors provided with same Mechanical Engineering; Lighting; Heating 24 Expired
US5574322A Motor, a printer having such a motor and a disk drive system having such a motor Mechanical Engineering; Lighting; Heating 23 Expired
US4508396A Method of producing bearing component Mechanical Engineering; Lighting; Heating 21 Expired
US5417507A Vertical motor, method of manufacturing same, polygon mirror motor using said motor, and bearing device for use in said motor Electricity 19 Expired
US6477133B1 Disk drive with unbalance correcting mechanism Physics 17 Expired
US5108198A Magnetic fluid bearing apparatus and motor having magnetic fluid bearing apparatus Mechanical Engineering; Lighting; Heating 16 Expired
US5493161A Sealed magnetic fluid bearing for polygon mirror drive motor Mechanical Engineering; Lighting; Heating 16 Expired
US5645355A Bearing unit Emerging Cross-Sectional Technologies 16 Expired
US6771460B2 Spindle motor and magnetic disc device using thereof having radial and thrust bearings Mechanical Engineering; Lighting; Heating 16 Expired
US6756715B2 Spindle motor Mechanical Engineering; Lighting; Heating 14 Expired
US5469008A Motor with a bearing lubricated by magnetic fluid Physics 14 Expired
US5035519A Submersible thrust bearing apparatus Mechanical Engineering; Lighting; Heating 13 Expired
US5810481A Oil retaining bearing unit and motor having oil retaining bearing unit Mechanical Engineering; Lighting; Heating 13 Expired
US5821655A Magnetic fluid bearing unit structure and motor having the same Electricity 12 Expired
US5541462A Rotary body bearing apparatus, motor and polygon mirror motor Electricity 12 Expired
US6243230A Disk drive unit with hydrodynamic fluid bearing unit and disk device with said drive unit Mechanical Engineering; Lighting; Heating 11 Expired
US6574186B2 Assembly method of motor using magnetic lubrication fluid Mechanical Engineering; Lighting; Heating 11 Expired
US6356408B1 Magnetic disk apparatus, including spindle motor having air flow passage in hub for pressure balance Emerging Cross-Sectional Technologies 10 Expired
US4746268A End face mechanical shaft seal for use in hydraulic machines and seal ring assembly for use in the shaft seal Mechanical Engineering; Lighting; Heating 10 Expired
USRE35718E Bearing apparatus General 8 Expired
US4529209A Hydraulic machine shaft seal with centrifugal removal of sand and soil particles Emerging Cross-Sectional Technologies 8 Expired
US4433432A X-Ray tube apparatus Electricity 7 Expired
US6469866B1 Spindle motor and magnetic disc device with hydrodynamic bearing Mechanical Engineering; Lighting; Heating 7 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.