Patent US3135074A successfully refreshed from Google Patents.
US3135074A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Twist drill grinding devices
Assignee: Individual
•
Filing: 1961-09-08
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Granted: 1964-06-02
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Expires: 1981-09-08
Abstract
No abstract record available.
Inventors
- 👤 George A Schwenzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:47
CPC Classifications
B; B24; B24B; B24B3/00; B24B3/24; B24B3/245
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
A TWIST DRILL GRINDING DEVICE HAVING MOTOR DRIVEN INVERTED END FOR END CONICAL GRINDING MEANS ADJACENT EACH TO THE OTHER ON PARALLEL SHAFTS, SAID GRINDING MEANS AND SHAFTS ARRANGED TO BE TILTED UPWARD AND DOWNWARD ABOUT A CENTRAL VERTICAL AXIS PERPENDICULAR TO THE AXIS OF SAID GRINDING MEANS WHILE GRINDING SAID TWIST DRILLS, SAID CONICAL GRINDING MEANS ROTATABLE TOWARDS EACH TO THE OTHER.
Claim 2
Dependent Claim
63 words
A TWIST DRILL GRINDING DEVICE HAVING MOTOR DRIVEN INVERTED END FOR END CONICAL GRINDING MEANS ADJACENT EACH TO THE OTHER ON PARALLEL SHAFTS, SAID GRINDING MEANS AND SHAFTS ARRANGED TO BE TILTED UPWARD AND DOWNWARD ABOUT A CENTRAL VERTICAL AXIS PERPENDICULAR TO THE AXIS OF SAID GRINDING MEANS WHILE GRINDING SAID TWIST DRILLS, SAID CONICAL GRINDING MEANS ROTATABLE TOWARDS EACH TO THE OTHER.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-06-02 | 1967-12-02 | 1968-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-02 | 1971-12-02 | 1972-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-02 | 1975-12-02 | 1976-06-02 | $7700.00 | Window Closed / Lapsed |