US3699558A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Angular position sensors
Assignee: Decca Ltd
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Filing: 1970-07-13
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Granted: 1972-10-17
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Expires: 1990-07-13
Abstract
Abstract A rotatable insulating disc carries a closed grid of conductors over one part of one side and a similar but open grid over another part. An oscillator is coupled to a coil which is parallel to the disc and produces a cyclically varying but symmetrical field through the disc. Two pairs of pick-up coils sense, for respective orthogonal directions, the distortion of the field by the closed grid and detector circuits coupled to the pick-up coils provide signals representing the sine and cosine of the angular position of the disc which may carry a compass needle.
Inventors
- 👤 Dennis Alfred Hendley
- 👤 Sipko L Boersma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:40
CPC Classifications
G; G01; G01C; G01C17/00; G01C17/02; G01C17/04; G01C17/20; G01C17/26
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
134 words
An angular position sensor for a compass needle, said sensor comprising a rotatable member mounted for rotation in accord with the rotation of said needle and coaxially therewith, said member extending in a plane normal to its axis of rotation, means for producing a cyclically varying magnetic field that is spatially regular about the axis of rotation of the said member, a conductive closed grid means of parallel conductors disposed on the said member and extending over it normal to said axis, whereby said field is distorted in accord with the member''s angular position, respective means for sensing the distortion of the field in each of two orthogonal directions normal to said axis and circuit means coupled to said means for sensing for deriving electrical signals representative of the sensed distortion in each direction.
Claim 2
Dependent Claim
134 words
An angular position sensor for a compass needle, said sensor comprising a rotatable member mounted for rotation in accord with the rotation of said needle and coaxially therewith, said member extending in a plane normal to its axis of rotation, means for producing a cyclically varying magnetic field that is spatially regular about the axis of rotation of the said member, a conductive closed grid means of parallel conductors disposed on the said member and extending over it normal to said axis, whereby said field is distorted in accord with the member''s angular position, respective means for sensing the distortion of the field in each of two orthogonal directions normal to said axis and circuit means coupled to said means for sensing for deriving electrical signals representative of the sensed distortion in each direction.
Claim 3
Dependent Claim
63 words
An angular position sensor as claimed in claim 1 in which the means for sensing each comprise two pick-up coils spanning regions displaced in a respective one of two orthogonal directions parallel to the said plane and the means for deriving electrical signals comprise means responsive to the difference between signals induced in the respective coils by the flux of the magnetic field.
Claim 4
Dependent Claim
35 words
An angular position sensor as claimed in claim 2 in which detector circuits are coupled to the pick-up coils for producing signals representative of the sine and cosine of the angular position of the member.
Claim 5
Dependent Claim
20 words
An angular position sensor as claimed in claim 2 in which each pair of coils span two abutting semicircular regions.
Claim 6
Dependent Claim
35 words
An angular position sensor as claimed in claim 4 in which the means for producing the magnetic field comprises a coil disposed parallel to the said plane and an electrical oscillator coupled to the coil.
Claim 7
Dependent Claim
26 words
An angular position sensor as claimed in claim 5 in which the member is disposed between the transmitting coil and the two pairs of pickup coils.
Claim 8
Dependent Claim
36 words
An angular position sensor as claimed in claim 6 in which the two pairs of pickup coils are arranged in spaced apart parallel planes and embrace regions substantially co-extensive with the area of the transmitting coil.
Claim 9
Dependent Claim
29 words
An angular position sensor as claimed in claim 7 in which the means for distorting comprises a conductive screen extending in said plane over part of the said member.
Claim 10
Dependent Claim
19 words
An angular position sensor as claimed in claim 8 in which thE screen comprises a closed grid of conductors.
Claim 11
Dependent Claim
41 words
An angular position sensor as claimed in claim 9 in which over a part of the member, opposite the part which carries the closed grid of conductors, is an open grid of otherwise similar configuration to that of the closed grid.
Claim 12
Dependent Claim
119 words
An angular position sensor for a compass needle which is rotatable about an axis, said sensor comprising an insulating disc mounted to move with said needle for rotation about said axis; a closed circuit gridded screen means of parallel conductors extending over part of said member on a surface thereof normal to said axis; a first coil disposed in a plane parallel to said disc and spaced from said disc along said axis; and a pair of coils extending in a second plane parallel to the said disc and spaced along said axis therefrom on the side of said disc remoter from said first coil, said coils of said pair of coils being spaced apart in said second plane.
Claim 13
Dependent Claim
119 words
An angular position sensor for a compass needle which is rotatable about an axis, said sensor comprising an insulating disc mounted to move with said needle for rotation about said axis; a closed circuit gridded screen means of parallel conductors extending over part of said member on a surface thereof normal to said axis; a first coil disposed in a plane parallel to said disc and spaced from said disc along said axis; and a pair of coils extending in a second plane parallel to the said disc and spaced along said axis therefrom on the side of said disc remoter from said first coil, said coils of said pair of coils being spaced apart in said second plane.
Claim 14
Dependent Claim
56 words
An angular position sensor as set forth in claim 11, further comprising a second pair of coils extending in a third plane parallel to said disc and spaced along said axis therefrom on the side thereof remoter from said first coil, said coils of said second pair of coils being spaced apart in said third plane.
Claim 15
Dependent Claim
45 words
An angular position sensor as set forth in claim 12, further comprising signal generating means coupled to said first coil and respective circuits each associated with one of said pairs of coils for determining differences in signals induced in the coils of the respective pair.
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) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |