US3297891A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brushless direct current motor
Assignee: Motors Liquidation Co
•
Filing: 1964-06-03
•
Granted: 1967-01-10
•
Expires: 1984-06-03
Abstract
No abstract record available.
Inventors
- 👤 Jr David J Foran
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:11
CPC Classifications
H; H02; H02K; H02K25/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
136 words
A BRUSHLESS DIRECT CURRENT ELECTRIC MOTOR INCLUDING, A FRAME, A FOUR POLE PERMANENT MAGNET ROTOR HAVING A SHAFT JOURNALLED IN SAID FRAME, FOUR POLE WOUND STATOR ENCIRCLING SAID ROTOR, THREE MAGNETIC REED SWITCHES CONNECTED BETWEEN A SOURCE OF DIRECT CURRENT POWER AND EACH PHASE OF SAID WOUND STATOR, AND PERMANENT MAGNET MEANS SEQUENTIALLY ACTUATING SAID SWITCH TO PRODUCE A SQUARE WAVE ROTATING MAGNETIC FLUX FIELD IN SAID STATOR SO AS TO CAUSE ROTATION OF SAID ROTOR, SAID MAGNETIC REED SWITCHES ARE MOUNTED ON A SUPPORT LOCATED AT RIGHT ANGLES TO THE AXIS OF SAID ROTOR SHAFT, WHEREIN SAID MAGNET MEANS COMPRISES THREE PERMANENT MAGNETS MOUNTED ON A SECOND PLATE AXIALLY SPACED FROM SAID FIRST PLATE, AND SLOTTED MAGNETIC SHIELDING MEANS CONNECTED TO SAID ROTOR SHAFT AND DISPOSED BETWEEN SAID PERMANENT MAGNETS AND SAID MAGNETIC REED SWITCHES.
Claim 2
Dependent Claim
136 words
A BRUSHLESS DIRECT CURRENT ELECTRIC MOTOR INCLUDING, A FRAME, A FOUR POLE PERMANENT MAGNET ROTOR HAVING A SHAFT JOURNALLED IN SAID FRAME, FOUR POLE WOUND STATOR ENCIRCLING SAID ROTOR, THREE MAGNETIC REED SWITCHES CONNECTED BETWEEN A SOURCE OF DIRECT CURRENT POWER AND EACH PHASE OF SAID WOUND STATOR, AND PERMANENT MAGNET MEANS SEQUENTIALLY ACTUATING SAID SWITCH TO PRODUCE A SQUARE WAVE ROTATING MAGNETIC FLUX FIELD IN SAID STATOR SO AS TO CAUSE ROTATION OF SAID ROTOR, SAID MAGNETIC REED SWITCHES ARE MOUNTED ON A SUPPORT LOCATED AT RIGHT ANGLES TO THE AXIS OF SAID ROTOR SHAFT, WHEREIN SAID MAGNET MEANS COMPRISES THREE PERMANENT MAGNETS MOUNTED ON A SECOND PLATE AXIALLY SPACED FROM SAID FIRST PLATE, AND SLOTTED MAGNETIC SHIELDING MEANS CONNECTED TO SAID ROTOR SHAFT AND DISPOSED BETWEEN SAID PERMANENT MAGNETS AND SAID MAGNETIC REED SWITCHES.
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) | 1970-01-09 | 1970-07-11 | 1971-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-01-09 | 1974-07-11 | 1975-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-01-09 | 1978-07-11 | 1979-01-10 | $7700.00 | Window Closed / Lapsed |