US4422041A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnet position sensing system
Assignee: United States Department of the Army
•
Filing: 1981-07-30
•
Granted: 1983-12-20
•
Expires: 2001-07-30
Abstract
Abstract Magnetic position sensing for an object is disclosed wherein the analogue the distance between an object and a sensor is detected for indicating changes in object position in one, two, or three dimensions. An accurate, and continous output signal indicative of object position and incremental changes in that position are obtained. Additionally, magnetic sensing provides motion sensing of a support structure or velocity and acceleration sensing of an object.
Inventors
- 👤 Jeffrey A. Lienau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:06
CPC Classifications
G; G01; G01B; G01B7/00; G01B7/003; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/20; G01D5/2006; G01D5/2033; G01P; G01P3/00; G01P3/64; G01P3/66; G01P3/665
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
160 words
A magnetic position sensing circuit comprising: an object having a longitudinal axis and adapted for displacement substantially along said axis; magnetic means disposed selectively on said object for producing a plurality of magnetic fields, said magnetic means being a plurality of spaced apart magnetic field producing members disposed around the circumference of the object for radiating individual magnetic fields circumferentially outward from the object; sensing means disposed adjacent to said object for sensing magnetic field strength indicative of lateral and longitudinal position changes of said magnetic means relative to said sensing means, said sensing means being a plurality of sensor elements disposed in a plurality of parallel planes passing through the object and each element being disposed for sensing positional changes in the object; signal processing means for indicating the changes in lateral and longitudinal position between said sensing means and said magnetic means; and a centerline axis normal to said planes, said sensor elements being equidistant from said centerline.
Claim 2
Dependent Claim
160 words
A magnetic position sensing circuit comprising: an object having a longitudinal axis and adapted for displacement substantially along said axis; magnetic means disposed selectively on said object for producing a plurality of magnetic fields, said magnetic means being a plurality of spaced apart magnetic field producing members disposed around the circumference of the object for radiating individual magnetic fields circumferentially outward from the object; sensing means disposed adjacent to said object for sensing magnetic field strength indicative of lateral and longitudinal position changes of said magnetic means relative to said sensing means, said sensing means being a plurality of sensor elements disposed in a plurality of parallel planes passing through the object and each element being disposed for sensing positional changes in the object; signal processing means for indicating the changes in lateral and longitudinal position between said sensing means and said magnetic means; and a centerline axis normal to said planes, said sensor elements being equidistant from said centerline.
Claim 3
Dependent Claim
20 words
A magnetic sensing circuit as set forth in claim 1 wherein said plurality of magnetic field producing members are electromagnets.
Claim 4
Dependent Claim
54 words
A magnetic sensing circuit as set forth in claim 2 wherein said object is cylindrical, and wherein said sensor elements disposed in plural planes comprise four sensor elements in each plane disposed along respective coordinate axes, each plane being substantially normal to the longitudinal axis of said object when said object is at rest.
Claim 5
Dependent Claim
78 words
A magnetic sensing circuit as set forth in claim 3 wherein respective first and second pairs of sensors being in said planes are disposed coaxially on opposite sides of said cylindrical object for sensing deviation of position of said object therebetween in response to object motion, and said signal processing means comprises a difference signal measuring system and recording circuit for indicating changes in position and attitude in response to movement of said cylindrical object through said planes.
References Cited (Backward Citations)
DE190289C
Cited
US3417700A
Cited
US3024453A
Cited
US3421080A
Cited
US3945459A
Cited
US3843923A
Cited
US3906339A
Cited
US4047816A
Cited
US4095145A
Cited
US4072281A
Cited
US4107601A
Cited
US4210865A
Cited
JPS55155202A
Cited
US4372192A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |