US3344291A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double insulated hand tool
Assignee: Millers Falls Co
•
Filing: 1964-11-23
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Granted: 1967-09-26
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Expires: 1984-11-23
Abstract
No abstract record available.
Inventors
- 👤 Leonard C Pratt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:49
CPC Classifications
H; H02; H02K; H02K7/00; H02K7/14; H02K7/145
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
150 words
IN AN ELECTRICALLY POWERED HAND TOOL, THE COMBINATION COMPRISING: A HOUSING; A SHAFT ROTATABLY MOUNTED WITHIN SAID HOUSING: AN ARMATURE CARRIED BY SAID SHAFT SUCH THAT A PORTION OF SAID SHAFT PROJECTS FROM SAID ARMATURE; A COMMUTATOR CARRIED BY SAID SHAFT AND OPERATIVELY CONNECTED TO SAID ARMATURE; COMMUTATOR BRUSH MEANS DISPOSED WITHIN SAID HOUSING AND OPERATIVELY ASSOCIATED WITH SAID COMMUTATOR; A FIELD STRUCTURE INCLUDING A FIELD CORE AND ASSOCIATED FIELD COIL DISPOSED WITHIN SAID HOUSING AND OPERATIVELY CONNECTED TO SAID ARMATURE; AND MEANS UPON SAID SHAFT FOR INSULATING SAID SHAFT; SAID SHAFT INSULATING MEANS COMPRISING A COATING OF ALUMINUM OXIDE PROVIDED ON SAID SHAFT THROUGHOUT THE LENGTH OF THE PORTION OF SAID SHAFT COEXTENSIVE WITH SAID ARMATURE; AND A PAPER SLEEVE OVERLYING THE ALUMINUM OXIDE ON THE PORTION OF SAID SHAFT COEXTENSIVE WITH THE END WINDINGS OF THE ARMATURE BUT EXTERNAL OF THE CONNECTION OF THE COMMUTATOR WITH SAID SHAFT.
Claim 2
Dependent Claim
150 words
IN AN ELECTRICALLY POWERED HAND TOOL, THE COMBINATION COMPRISING: A HOUSING; A SHAFT ROTATABLY MOUNTED WITHIN SAID HOUSING: AN ARMATURE CARRIED BY SAID SHAFT SUCH THAT A PORTION OF SAID SHAFT PROJECTS FROM SAID ARMATURE; A COMMUTATOR CARRIED BY SAID SHAFT AND OPERATIVELY CONNECTED TO SAID ARMATURE; COMMUTATOR BRUSH MEANS DISPOSED WITHIN SAID HOUSING AND OPERATIVELY ASSOCIATED WITH SAID COMMUTATOR; A FIELD STRUCTURE INCLUDING A FIELD CORE AND ASSOCIATED FIELD COIL DISPOSED WITHIN SAID HOUSING AND OPERATIVELY CONNECTED TO SAID ARMATURE; AND MEANS UPON SAID SHAFT FOR INSULATING SAID SHAFT; SAID SHAFT INSULATING MEANS COMPRISING A COATING OF ALUMINUM OXIDE PROVIDED ON SAID SHAFT THROUGHOUT THE LENGTH OF THE PORTION OF SAID SHAFT COEXTENSIVE WITH SAID ARMATURE; AND A PAPER SLEEVE OVERLYING THE ALUMINUM OXIDE ON THE PORTION OF SAID SHAFT COEXTENSIVE WITH THE END WINDINGS OF THE ARMATURE BUT EXTERNAL OF THE CONNECTION OF THE COMMUTATOR WITH SAID SHAFT.
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GB725842A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-09-25 | 1971-03-27 | 1971-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-09-25 | 1975-03-27 | 1975-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-09-25 | 1979-03-27 | 1979-09-26 | $7700.00 | Window Closed / Lapsed |