Inventor
Charles J. Cheever
Inventor
Beaverton, OR, US
Overview
Patents· 7 as inventor
Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.
F16Cprimary
F16CShafts32%
H02KDynamo-electric machines27%
G11BInformation storage based on relative movement between record carrier and transducer18%
B21HMaking particular metal objects by rolling, e.g. screws, wheels, rings, barrels, balls5%
B21JForging5%
B21KMaking forged or pressed metal products, e.g. horse-shoes, rivets, bolts or wheels5%
F16JPistons5%
Y10TTechnical subjects covered by former us classification5%
PatentTitleYear
6,108,909'Groove forming processes for shaft outer diameter'20005,847,479'Self-pressure-balanced hydrodynamic bearing spindle motor'19985,770,906'Compact electric motor construction employing fluid bearings'19985,718,516'Spindle motors with hard coated hydrodynamic bearings'19985,689,146'Conical bearing system for spindle motors'19975,536,088'Fluid bearings for electronic spindle motors'19964,694,213'Ferrofluid seal for a stationary shaft and a rotating hub'1987Career & activity timeline
Assembled from patent assignee/location history and declaration credentials.
1987Patents assigned to FERROFLUIDICS CORP (1)· patent assignee history
1987Based in Nashua, NH, US· patent location history
1996–1997Patents assigned to SYNEKTRON CORP (2)· patent assignee history
1996–2000Based in Beaverton, OR, US· patent location history
1998–2000Patents assigned to SAE MAGNETICS HK LTD (4)· patent assignee history
Inventor activity
Assignee and location history derived from the patent record.
Assignees
| Assignee | Patents | Span |
|---|---|---|
| SAE MAGNETICS HK LTD | 4 | 1998–2000 |
| SYNEKTRON CORP | 2 | 1996–1997 |
| FERROFLUIDICS CORP | 1 | 1987 |
Locations
| Location | Patents | Span |
|---|---|---|
| Beaverton, OR, US | 6 | 1996–2000 |
| Nashua, NH, US | 1 | 1987 |