Patent US3621613A successfully refreshed from Google Patents.
US3621613A
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US
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Method and apparatus for thinning the web of a drill
Assignee: GROB AND TESKER CORP
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Filing: 1969-05-15
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Granted: 1971-11-23
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Expires: 1989-05-15
Abstract
Abstract TO THIN THE WEB OF A DRILL, THE DRILL IS ORBITED SO THAT, ONCE DURING EACH ORBIT, ITS WEB CONTACTS A ROTATING GRINDING WHEEL THAT IS POSITIONED APPROXIMATELY AT A 25DEGREE ANGLE FROM THE HORIZONTAL. THE GRINDING WHEEL ABRADES THE WEBS TO FORM A RECESS HAVING A RADIUS DETERMINED BY THE RADIUS OF THE ORBIT. THE RADIUS OF THE ORBIT MAY BE ADJUSTED WHILE THE DRILL IS ORBITING.
Inventors
- 👤 Theodore Grob
- 👤 Donald H Tesker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:25
CPC Classifications
B; B24; B24B; B24B3/00; B24B3/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-22 | 1975-05-24 | 1975-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-22 | 1979-05-24 | 1979-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-22 | 1983-05-24 | 1983-11-23 | $7700.00 | Window Closed / Lapsed |