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US3135074A Expired / Lapsed US ⏱️ 0.0 years remaining

Twist drill grinding devices

Assignee: Individual
•
Filing: 1961-09-08
•
Granted: 1964-06-02
•
Expires: 1981-09-08
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Abstract

No abstract record available.

Inventors

  • 👤 George A Schwenzer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 07:24
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)

US288069A Cited
US1042817A Cited
US2017532A Cited
US2177644A Cited
US2228385A Cited

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

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