US4311933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brushless direct current motor
Assignee: Philips North America LLC
•
Filing: 1979-08-27
•
Granted: 1982-01-19
•
Expires: 1999-08-27
Abstract
Abstract A brushless D.C. motor has electrical power switched between the phase windings by means of a circuit which includes a plurality of hall effect switches. The hall effect switches are operated by a plurality of arcuate commutating magnets which are radially polarized and are disposed axially adjacent to field magnets which are also radially polarized. Ordinarily, the direction of radial polarization of the commutating magnets and the field magnets will be opposite.
Inventors
- 👤 William D. Riggs
- 👤 Joseph J. Schegan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:09
CPC Classifications
H; H02; H02K; H02K29/00; H02K29/06; H02K29/08; Y; Y10; Y10S; Y10S310/00; Y10S310/03
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
56 words
A multipole multiphase brushless direct current motor having a rotor which includes a plurality of angularly spaced field magnets and a stator having phase windings and a circuit for switching electric power to said phase windings which comprises a plurality of hall effect switches and a plurality of angularly spaced commutating magnets carried on said rotor.
Claim 2
Dependent Claim
56 words
A multipole multiphase brushless direct current motor having a rotor which includes a plurality of angularly spaced field magnets and a stator having phase windings and a circuit for switching electric power to said phase windings which comprises a plurality of hall effect switches and a plurality of angularly spaced commutating magnets carried on said rotor.
Claim 3
Dependent Claim
22 words
The apparatus as described in claim 1 wherein each of said commutating magnets is axially adjacent to one of said field magnets.
Claim 4
Dependent Claim
19 words
The apparatus as described in claim 2 wherein said field magnets and said commutating magnets are both radially polarized.
Claim 5
Dependent Claim
21 words
The apparatus as described in claim 3 wherein the direction of radial polarization of said field and commutating magnets is opposite.
Claim 6
Dependent Claim
17 words
The apparatus as described in claim 4 wherein said hall effect switches are carried on said stator.
Claim 7
Dependent Claim
21 words
The apparatus as described in claim 5 wherein said apparatus includes one hall effect switch for each phase of said motor.
Claim 8
Dependent Claim
32 words
The apparatus as described in claim 6 further including a printed circuit board which is part of said stator and wherein said hall effect switches are carried on said printed circuit board.
References Cited (Backward Citations)
US3631272A
Cited
US4011475A
Cited
US4115715A
Cited
US4169990A
Cited
US4167671A
Cited
US4197489A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-01-18 | 1985-07-20 | 1986-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-18 | 1989-07-20 | 1990-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-18 | 1993-07-20 | 1994-01-19 | $7700.00 | Window Closed / Lapsed |