US3681669A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic transducer
Assignee: Pye Electronic Products Ltd
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Filing: 1971-03-22
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Granted: 1972-08-01
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Expires: 1991-03-22
Abstract
Abstract A magnetic transducer comprises a magnetic assembly producing a magnetic field varying over a region and a pick-up assembly located in said region and consisting of at least one magnetosensitive semiconductor device having a unidirectional voltage applied to it. Relative movement between the magnetic assembly and the pick-up assembly causes variation of the magnetic field influencing the pick-up assembly and enables a correspondingly variable output signal to be derived from said pick-up assembly.
Inventors
- 👤 Peter John Henry Ayers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:04
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/142; G01D5/145
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
183 words
A magnetic transducer comprising a magnetic assembly producing a magnetic field varying over a region and a pick-up assembly located in said region and comprising at least one magnetosensitive semiconductor device, whereby relative movement between said magnetic assembly and said pick-up assembly causes variation of the magnetic field influencing said pick-up assembly and enables a correspondingly variable output signal to be derived from said pick-up assembly, and wherein the magnetic assembly comprises two discs of magnetic material separated by an annular magnet secured between the discs and having one pole adjacent one disc and its other pole adjacent the other disc, a pole piece extending around at least part of the circumference of one disc and extending towards the other disc, a further pOle piece extending at least partly around the circumference of the other disc and extending towards the first disc, the pole pieces being so disposed as to provide an air gap between the pole pieces, the axis of the gap being inclined to a plane through the axis of the assembly to provide said magnetic field varying over said region.
Claim 2
Dependent Claim
183 words
A magnetic transducer comprising a magnetic assembly producing a magnetic field varying over a region and a pick-up assembly located in said region and comprising at least one magnetosensitive semiconductor device, whereby relative movement between said magnetic assembly and said pick-up assembly causes variation of the magnetic field influencing said pick-up assembly and enables a correspondingly variable output signal to be derived from said pick-up assembly, and wherein the magnetic assembly comprises two discs of magnetic material separated by an annular magnet secured between the discs and having one pole adjacent one disc and its other pole adjacent the other disc, a pole piece extending around at least part of the circumference of one disc and extending towards the other disc, a further pOle piece extending at least partly around the circumference of the other disc and extending towards the first disc, the pole pieces being so disposed as to provide an air gap between the pole pieces, the axis of the gap being inclined to a plane through the axis of the assembly to provide said magnetic field varying over said region.
Claim 3
Dependent Claim
98 words
A transducer as claimed in claim 1, wherein the pick-up assembly comprises a magnetodiode mounted between pole pieces of magnetic material and positioned relative to said air gap so that in one position of rotation of said magnetic assembly, the pick-up assembly is axially displaced from said gap and experiences a relatively weak magnetic field and as the magnetic assembly is rotated the air gap moves relative to the pick-up assembly to a position where the pick-up assembly is more symmetrically disposed with respect to the gap and the magnetic field experienced by the pick-up assembly is greater.
Claim 4
Dependent Claim
80 words
A transducer as claimed in claim 2, wherein the pick-up assembly includes a second magnetodiode connected in series with the first magnetodiode and mounted between the pole pieces so that it experiences the same ambient conditions as the first magnetodiode but said second magnetodiode being orientated so that the magnetic field traverses it in opposite sense to its direction through the first magnetodiode whereby the output signal obtained is virtually independent of temperature variations and dependent only on angular position.
Claim 5
Dependent Claim
49 words
A transducer as claimed in claim 1, wherein the pole pieces extend completely around the discs and upon rotation of the magnetic assembly, the output signal from the pick-up assembly is a waveform varying between a minimum and a maximum value during each complete rotation of the magnetic assembly.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |