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US3984713A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic speed sensor with compensating pole

Assignee: Bendix Corp
•
Filing: 1975-07-01
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Granted: 1976-10-05
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Expires: 1995-07-01
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Abstract

Abstract A speed sensor for a vehicle wheel having a rotating tone wheel and a stationary magnetic sensor with a sensing pole proximate the tone wheel teeth and a compensating pole proximate the tone wheel spaced from the tone wheel teeth. The sensing pole and compensating pole are secured to the ends of a permanent magnet in U-shaped configuration and coils connected in series opposition are wound on the sensing and compensating poles. Noise components generated in the sensing coil with the speed signal voltage due to axial misalignment and vibration of the tone wheel are cancelled by corresponding noise components generated in the compensating coil to provide a substantially noise free signal voltage corresponding to wheel speed.

Inventors

  • 👤 Rex Wallace Presley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 20:54
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/481; G01P3/488

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 129 words
A speed sensor for a vehicle wheel comprising a tone wheel driven by the vehicle and subject to axial misalignment and vibration, the tone wheel being made of magnetic material and having a continuous portion and a toothed portion, and sensing means having a sensing pole at one side of the tone wheel proximate the toothed portion and a compensating pole at the same side of the tone wheel proximate the continuous portion and remote from the toothed portion, coil means on the poles, and means for magnetizing the poles to induce a signal voltage across the coil means corresponding to wheel speed and substantially free of noise components due to axial misalignment and vibration of the tone wheel upon relative rotation of the tone wheel and sensing means.
Claim 2
Dependent Claim 129 words
A speed sensor for a vehicle wheel comprising a tone wheel driven by the vehicle and subject to axial misalignment and vibration, the tone wheel being made of magnetic material and having a continuous portion and a toothed portion, and sensing means having a sensing pole at one side of the tone wheel proximate the toothed portion and a compensating pole at the same side of the tone wheel proximate the continuous portion and remote from the toothed portion, coil means on the poles, and means for magnetizing the poles to induce a signal voltage across the coil means corresponding to wheel speed and substantially free of noise components due to axial misalignment and vibration of the tone wheel upon relative rotation of the tone wheel and sensing means.
Claim 3
Dependent Claim 89 words
A speed sensor as described in claim 1 in which the coil means includes a coil wound on the sensing pole for providing a signal voltage corresponding to wheel speed and to noise components due to axial misalignment and vibration of the tone wheel, and a coil wound on the compensating pole for providing a signal voltage corresponding to the noise components due to axial misalignment and vibration of the tone wheel, the coils being connected in series opposition to cancel the signal voltage due to the noise components.
Claim 4
Dependent Claim 21 words
A speed sensor as described in claim 1 in which the magnetizing means is a permanent magnet connected between the poles.
Claim 5
Dependent Claim 30 words
A speed sensor as described in claim 3 in which the permanent magnet and poles are arranged in U-shaped configuration with the ends of the poles proximate the tone wheel.
Claim 6
Dependent Claim 47 words
A speed sensor as described in claim 1 in which the toothed portion of the tone wheel comprises a plurality of equally spaced teeth and the spaces between the teeth are substantially the same size as the teeth and the sensing pole is smaller than the teeth.

References Cited (Backward Citations)

US2161256A Cited
US2756357A Cited
US2820915A Cited
US2853638A Cited
US3564313A Cited
US3825782A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-10-05 1980-04-05 1980-10-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-10-05 1984-04-05 1984-10-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-10-05 1988-04-05 1988-10-05 $7700.00 Window Closed / Lapsed

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