US4215286A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable reluctance electromagnetic pickup
Assignee: Motors Liquidation Co
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Filing: 1978-11-13
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Granted: 1980-07-29
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Expires: 1998-11-13
Abstract
Abstract A variable reluctance pickup for producing electrical pulses in response to the rotation of an adjacent toothed wheel comprises a probe assembly situated tangentially to the path of the wheel teeth. The sensor comprises an elongated core surrounded by a coil and having permanent magnets of opposed polarity at each end of the core. A pole piece extending laterally from one end of the core extends to a point adjacent the path of the teeth of the rotating part. The electrical pulses produced upon part rotation are double the size of pulses produced in the case where only one magnet of equivalent strength to the two magnets is used.
Inventors
- 👤 Michael W. Ornee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:55
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/481; G01P3/488
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
209 words
A variable reluctance pulse generator for sensing the rotation of a rotary member comprising a toothed member of magnetic material driven by the said rotary member, an elongated core member of magnetic material having first and second ends, a coil around the core member between the ends, a pole piece of magnetic material extending from the first end of the core member and positioned close to the toothed member and periodically aligned with the teeth thereof during rotation, a first magnet adjacent the second end of the core member to provide a magnetic flux through the core member, the pole piece and the toothed member, the said flux varying between a high value and a low value as the teeth of the toothed member are aligned and nonaligned, respectively, with the pole piece, whereby an emf is induced in the coil as the flux varies, and a second magnet adjacent the first end of the core member arranged in opposition to the first magnet for bucking the low value flux in the core when the pole piece is nonaligned with the teeth of the toothed member to effectively reduce the low value flux from the first magnet whereby the flux variation is increased and the induced emf is increased.
Claim 2
Dependent Claim
209 words
A variable reluctance pulse generator for sensing the rotation of a rotary member comprising a toothed member of magnetic material driven by the said rotary member, an elongated core member of magnetic material having first and second ends, a coil around the core member between the ends, a pole piece of magnetic material extending from the first end of the core member and positioned close to the toothed member and periodically aligned with the teeth thereof during rotation, a first magnet adjacent the second end of the core member to provide a magnetic flux through the core member, the pole piece and the toothed member, the said flux varying between a high value and a low value as the teeth of the toothed member are aligned and nonaligned, respectively, with the pole piece, whereby an emf is induced in the coil as the flux varies, and a second magnet adjacent the first end of the core member arranged in opposition to the first magnet for bucking the low value flux in the core when the pole piece is nonaligned with the teeth of the toothed member to effectively reduce the low value flux from the first magnet whereby the flux variation is increased and the induced emf is increased.
Claim 3
Dependent Claim
233 words
A variable reluctance pulse generator for sensing the rotation of a rotary member comprising a toothed member of magnetic material driven by the said rotary member, an elongated core member of magnetic material having a central axis and first and second ends, a coil around the core member between the ends, a pole piece of magnetic material extending laterally from the first end of the core member and positioned close to the toothed member and periodically aligned with the teeth thereof during rotation, a first magnet adjacent the second end of the core member and aligned with the axis of the core member to provide a magnetic flux through the core member, the pole piece and the toothed member, the said flux varying between a high value and a low value as the teeth of the toothed member are aligned and nonaligned, respectively, with the pole piece, whereby an emf is induced in the coil as the flux varies, and a second magnet adjacent the first end of the core member and aligned with the axis of the core member and arranged in opposition to the first magnet for bucking the low value flux in the core when the pole piece is nonaligned with the teeth of the toothed member to effectively reduce the low value flux from the first magnet whereby the flux variation is increased and the induced emf is increased.
Claim 4
Dependent Claim
233 words
A variable reluctance pulse generator for sensing the rotation of a rotary member comprising a toothed member of magnetic material driven by the said rotary member, an elongated core member of magnetic material having a central axis and first and second ends, a coil around the core member between the ends, a pole piece of magnetic material extending laterally from the first end of the core member and positioned close to the toothed member and periodically aligned with the teeth thereof during rotation, a first magnet adjacent the second end of the core member and aligned with the axis of the core member to provide a magnetic flux through the core member, the pole piece and the toothed member, the said flux varying between a high value and a low value as the teeth of the toothed member are aligned and nonaligned, respectively, with the pole piece, whereby an emf is induced in the coil as the flux varies, and a second magnet adjacent the first end of the core member and aligned with the axis of the core member and arranged in opposition to the first magnet for bucking the low value flux in the core when the pole piece is nonaligned with the teeth of the toothed member to effectively reduce the low value flux from the first magnet whereby the flux variation is increased and the induced emf is increased.
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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) | 1983-07-29 | 1984-01-28 | 1984-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-29 | 1988-01-28 | 1988-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-29 | 1992-01-28 | 1992-07-29 | $7700.00 | Window Closed / Lapsed |