US4295070A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means for providing a mechanically definable selected trigger interval in a flywheel magneto
Assignee: Svenska Electromagneter AB
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Filing: 1979-06-14
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Granted: 1981-10-13
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Expires: 1999-06-14
Abstract
Abstract In the disclosed ignition apparatus for internal combustion engines provided with flywheel magnetos, the ignition spark interval is purely mechanically provided at the manufacturing stage. In the direction of rotation, the edges of both pole shoes and core legs which meet each other are sharply defined. The pole shoe, first in the direction of rotation, is formed so that it substantially coacts with the leg, second in the direction of rotation, when the leading edge of the second pole shoe comes into coaction with the front edge of the leg situated first.
Inventors
- 👤 Sven H. Johansson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:39
CPC Classifications
F; F02; F02P; F02P1/00; F02P1/08; F02P1/086
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
288 words
A flywheel magneto in an electronic ignition circuit, including: (a) a flywheel; (b) a ferromagnetic core having in succession a first leg, a second leg, and a third leg, each leg terminating at the periphery of said flywheel; (c) a trigger coil in said circuit and carried on said first leg, and a charging coil carried on said third leg; (d) a pair of magnetic pole shoes and a permanent magnet disposed between said shoes and jointly molded into said flywheel, said pole shoes being disposed at the periphery of said flywheel in magnetic circuit with said permanent magnet, a first of said shoes, situated first in the direction of rotation of said flywheel, having such extent that its flux can coact with said first and second legs in one position, said first pole shoe having a notch underlying its leading edge for limiting initial flux transfer to said second leg, the leading edge of said one shoe being sharply defined, the leading edge of a second of said shoes, thereafter, coming to the first encountered edge of said first leg where the magnetic flux of said second shoe begins to coact with magnetic flux in said second leg; (e) a first-encountered edge of each of said first and second legs being sharply defined and registering with the path of movement of said pole shoes; and (f) the distance between said leading edges defining the duration of a triggering signal induced in said trigger coil, said signal beginning in response to said leading edge of said first shoe encountering the first-encountered edge of said second leg, and said signal ending in response to said leading edge of said second shoe encountering the first-encountered edge of said second leg.
Claim 2
Dependent Claim
288 words
A flywheel magneto in an electronic ignition circuit, including: (a) a flywheel; (b) a ferromagnetic core having in succession a first leg, a second leg, and a third leg, each leg terminating at the periphery of said flywheel; (c) a trigger coil in said circuit and carried on said first leg, and a charging coil carried on said third leg; (d) a pair of magnetic pole shoes and a permanent magnet disposed between said shoes and jointly molded into said flywheel, said pole shoes being disposed at the periphery of said flywheel in magnetic circuit with said permanent magnet, a first of said shoes, situated first in the direction of rotation of said flywheel, having such extent that its flux can coact with said first and second legs in one position, said first pole shoe having a notch underlying its leading edge for limiting initial flux transfer to said second leg, the leading edge of said one shoe being sharply defined, the leading edge of a second of said shoes, thereafter, coming to the first encountered edge of said first leg where the magnetic flux of said second shoe begins to coact with magnetic flux in said second leg; (e) a first-encountered edge of each of said first and second legs being sharply defined and registering with the path of movement of said pole shoes; and (f) the distance between said leading edges defining the duration of a triggering signal induced in said trigger coil, said signal beginning in response to said leading edge of said first shoe encountering the first-encountered edge of said second leg, and said signal ending in response to said leading edge of said second shoe encountering the first-encountered edge of said second leg.
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) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |