US4970463A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature stable proximity sensor with sensing of flux emanating from the lateral surface of a magnet
Assignee: Aumovio Systems Inc
•
Filing: 1989-03-13
•
Granted: 1990-11-13
•
Expires: 2009-03-13
Abstract
Abstract A ferrous object sensor assembly is capable of sensing the presence or absence of an object of high magnetic permeability, such as a tooth or notch on a rotatably mounted ferrous wheel at zero speed and immediately upon power-up and, thus, may also be used as a proximity sensor. The ferrous object sensor assembly is comprised of a permanent magnet and a magnetic flux responsive sensor having a sensing plane which produces an electrical output signal which varies as a function of the change in magnetic flux density. The ferrous body sensor assembly does not rely upon pole face magnetism as some known conventional sensors but, rather, relies upon a the radial component of magnetic flux density emanating from a lateral surface of the magnet, intermediate opposing pole faces. Since the ferrous object sensor assembly does not rely on pole face magnetism, its electrical output signal is relatively stable over a relatively wide temperature range.
Inventors
- 👤 Ronald J. Wolf
- 👤 Larry Hedeen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:18
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/08
Claims Analysis
Total Claims: 62
Claim 1
Independent Claim
169 words
A ferrous body proximity sensor assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet for use in a motor vehicle comprising: a permanent magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means having a sensing plane for sensing said magnetic flux emanating from the lateral surface of said magnet applied to said sensing plane and producing an output voltage signal as a function of the change in magnetic flux density applied to said sensing plane resulting from the proximity of said metallic body relative to one of said pole faces; wherein said sensor means is attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly.
Claim 2
Dependent Claim
169 words
A ferrous body proximity sensor assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet for use in a motor vehicle comprising: a permanent magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means having a sensing plane for sensing said magnetic flux emanating from the lateral surface of said magnet applied to said sensing plane and producing an output voltage signal as a function of the change in magnetic flux density applied to said sensing plane resulting from the proximity of said metallic body relative to one of said pole faces; wherein said sensor means is attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly.
Claim 3
Dependent Claim
42 words
A ferrous body sensor as recited in claim 1, wherein said sensor means is a switching type device and provides an electrical output signal when magnetic flux density of a predetermined polarity above a predetermined value is applied to said sensing plane.
Claim 4
Dependent Claim
41 words
A ferrous body sensor as recited in claim 1, wherein said sensor means is a switching type device and provides an electrical output signal when magnetic flux of a predetermined polarity below a predetermined value is applied to said sensing plane.
Claim 5
Dependent Claim
31 words
A ferrous body sensor as recited in claim 1, wherein said sensor means provides an electrical output signal, linearly related to the change in magnetic flux applied to said sensing plane.
Claim 6
Dependent Claim
180 words
A ferrous proximity sensor assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet for use in a motor vehicle comprising: a permanent magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means having a sensing plane for sensing said magnetic flux emanating from the lateral surface of said magnet and producing an output voltage signal as a function of the change in magnetic flux density applied to said sensing plane resulting from the proximity of said metallic body relative to one of said pole faces; wherein said sensor means is attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly; and means, rigidly attached to said sensor means, for concentrating said magnetic flux through said sensing means.
Claim 7
Dependent Claim
180 words
A ferrous proximity sensor assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet for use in a motor vehicle comprising: a permanent magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means having a sensing plane for sensing said magnetic flux emanating from the lateral surface of said magnet and producing an output voltage signal as a function of the change in magnetic flux density applied to said sensing plane resulting from the proximity of said metallic body relative to one of said pole faces; wherein said sensor means is attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly; and means, rigidly attached to said sensor means, for concentrating said magnetic flux through said sensing means.
Claim 8
Dependent Claim
26 words
A ferrous body sensor as recited in claim 5, wherein said concentrating means is attached on a surface of said sensor means opposite said sensing plane.
Claim 9
Dependent Claim
21 words
A ferrous body sensor as recited in claim 1, wherein said sensor means is attached to said magnet with an adhesive.
Claim 10
Dependent Claim
15 words
A ferrous body sensor as recited in claim 7, wherein said adhesive is an epoxy.
Claim 11
Dependent Claim
15 words
A ferrous body sensor as recited in claim 1, wherein said predetermined cross-section is uniform.
Claim 12
Dependent Claim
15 words
A ferrous body sensor as recited in claim 9, wherein said predetermined cross-section is circular.
Claim 13
Dependent Claim
15 words
A ferrous body sensor as recited in claim 9, wherein said predetermined cross-section is rectangular.
Claim 14
Dependent Claim
15 words
A ferrous body sensor as recited in claim 9, wherein said predetermined cross-section is D-shaped.
Claim 15
Dependent Claim
15 words
A ferrous body sensor as recited in claim 9, wherein said predetermined cross-section is non-uniform.
Claim 16
Dependent Claim
184 words
A Hall effect sensor assembly for use in a motor vehicle for sensing the presence of a tooth or a notch on a ferrous vane or wheel disposed adjacent one pole face of a magnet comprising: a magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; means for providing an output voltage signal representative of the proximity of a tooth or notch on a ferrous vane or wheel including a Hall effect sensor as a function of said magnetic flux emanating from said lateral surface of said magnet resulting from the proximity of said tooth or notch to one of said pole faces; and means for attaching said providing means to the surface of said magnet along said magnetic axis, intermediate said opposing pole faces, such that said providing means is substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly.
Claim 17
Dependent Claim
184 words
A Hall effect sensor assembly for use in a motor vehicle for sensing the presence of a tooth or a notch on a ferrous vane or wheel disposed adjacent one pole face of a magnet comprising: a magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; means for providing an output voltage signal representative of the proximity of a tooth or notch on a ferrous vane or wheel including a Hall effect sensor as a function of said magnetic flux emanating from said lateral surface of said magnet resulting from the proximity of said tooth or notch to one of said pole faces; and means for attaching said providing means to the surface of said magnet along said magnetic axis, intermediate said opposing pole faces, such that said providing means is substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly.
Claim 18
Dependent Claim
20 words
A Hall effect sensor assembly as recited in claim 14, further including a ferrous piece attached to said providing means.
Claim 19
Dependent Claim
16 words
A Hall effect sensor assembly as recited in claim 14, wherein said predetermined cross-section is uniform.
Claim 20
Dependent Claim
16 words
A Hall effect sensor assembly as recited in claim 14, wherein said predetermined cross-section is non-uniform.
Claim 21
Dependent Claim
45 words
A Hall effect sensor assembly as recited in claim 14, wherein said providing means includes a Hall effect integrated circuit having a sensing surface which provides an output voltage signal as a function of the change in magnetic flux density applied to said sensing surface.
Claim 22
Dependent Claim
182 words
A Hall effect sensor assembly for sensing the presence of a tooth or a notch on a ferrous vane or wheel disposed adjacent one pole face of a magnet comprising: a magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; means for providing an output voltage signal in the presence of a tooth or notch on a ferrous vane or wheel disposed adjacent one pole face in a stationary position including a Hall effect sensor as a function of the magnetic flux emanating from the lateral surface of said magnet resulting from the proximity of said tooth or notch to one of said pole faces; and means for attaching said providing means to the lateral surface of said magnet, intermediate opposing pole faces, such that said providing means is substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly.
Claim 23
Dependent Claim
182 words
A Hall effect sensor assembly for sensing the presence of a tooth or a notch on a ferrous vane or wheel disposed adjacent one pole face of a magnet comprising: a magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; means for providing an output voltage signal in the presence of a tooth or notch on a ferrous vane or wheel disposed adjacent one pole face in a stationary position including a Hall effect sensor as a function of the magnetic flux emanating from the lateral surface of said magnet resulting from the proximity of said tooth or notch to one of said pole faces; and means for attaching said providing means to the lateral surface of said magnet, intermediate opposing pole faces, such that said providing means is substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor assembly.
Claim 24
Dependent Claim
16 words
A Hall effect sensor assembly as recited in claim 19, wherein said predetermined cross-section is uniform.
Claim 25
Dependent Claim
16 words
A Hall effect sensor assembly as recited in claim 19, wherein said predetermined cross-section is non-uniform.
Claim 26
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means includes an adhesive.
Claim 27
Dependent Claim
16 words
A Hall effect sensor assembly as recited in claim 22, wherein said adhesive is an epoxy.
Claim 28
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means is a tape.
Claim 29
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means includes a carrier.
Claim 30
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 25, wherein said carrier is formed from plastic.
Claim 31
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 25, wherein said carrier is formed from ceramic.
Claim 32
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 25, wherein said carrier is formed from paper.
Claim 33
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 25, wherein said carrier is formed from metal.
Claim 34
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means includes an encapsulant.
Claim 35
Dependent Claim
21 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means includes a housing which encloses the assembly.
Claim 36
Dependent Claim
18 words
A Hall effect sensor assembly as recited in claim 31, wherein said housing is formed from a plastic.
Claim 37
Dependent Claim
18 words
A Hall effect sensor assembly as recited in claim 31, wherein said housing is formed from a metal.
Claim 38
Dependent Claim
18 words
A Hall effect sensor assembly as recited in claim 31, wherein said housing is formed from a ceramic.
Claim 39
Dependent Claim
19 words
A Hall effect sensor assembly as recited in claim 31, wherein said housing is formed from a paper fiber.
Claim 40
Dependent Claim
14 words
A Hall effect sensor assembly as recited in claim 31, further including an encapsulant.
Claim 41
Dependent Claim
15 words
A Hall effect sensor assembly as recited in claim 31, further including a potting compound.
Claim 42
Dependent Claim
16 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means includes casting.
Claim 43
Dependent Claim
16 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means includes overmolding.
Claim 44
Dependent Claim
17 words
A Hall effect sensor assembly as recited in claim 19, wherein said attaching means includes insert molding.
Claim 45
Dependent Claim
41 words
A Hall effect sensor assembly as recited in claim 19, wherein said providing means includes a Hall effect sensor integrated circuit which provides an output voltage signal as a function of the change in magnetic flux density applied to the sensor.
Claim 46
Independent Claim
167 words
A method for detecting the presence of a tooth or notch on a ferrous vane or wheel disposed adjacent one pole face of a magnet comprising the steps of: (a) providing a magnet having North and South poles defining opposing pole faces, a lateral surface therebetween and a magnetic axis connecting said opposing pole faces for generating a source of magnetic flux emanating from said lateral surface; (b) attaching a Hall effect sensor intermediate said opposing pole faces of the magnet forming an assembly such that said Hall effect sensor is substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor to provide an output voltage signal representative of a change in the magnetic flux density emanating from said lateral surface resulting from the proximity of said tooth or notch to one of said pole faces; and (c) disposing said assembly such that one or the other of said pole faces is disposed adjacent said tooth or notch.
Claim 47
Independent Claim
167 words
A method for detecting the presence of a tooth or notch on a ferrous vane or wheel disposed adjacent one pole face of a magnet comprising the steps of: (a) providing a magnet having North and South poles defining opposing pole faces, a lateral surface therebetween and a magnetic axis connecting said opposing pole faces for generating a source of magnetic flux emanating from said lateral surface; (b) attaching a Hall effect sensor intermediate said opposing pole faces of the magnet forming an assembly such that said Hall effect sensor is substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor to provide an output voltage signal representative of a change in the magnetic flux density emanating from said lateral surface resulting from the proximity of said tooth or notch to one of said pole faces; and (c) disposing said assembly such that one or the other of said pole faces is disposed adjacent said tooth or notch.
Claim 48
Independent Claim
140 words
A method for making a Hall effect sensor assembly adapted to sense the presence or absence of a tooth on a ferrous vane or wheel adjacent one pole face of a magnet comprising the steps: (a) providing a magnet having North and South poles defining opposing pole faces and a lateral surface therebetween for generating magnetic flux emanating from said lateral surface; (b) providing a Hall effect sensor which generates an output voltage signal in response to a change in magnetic flux density emanating from said lateral surface resulting from the proximity or absence of said tooth or notch to one of said pole faces; and (c) attaching said sensor to said lateral surface of the magnet so as to be substantially response to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor.
Claim 49
Independent Claim
140 words
A method for making a Hall effect sensor assembly adapted to sense the presence or absence of a tooth on a ferrous vane or wheel adjacent one pole face of a magnet comprising the steps: (a) providing a magnet having North and South poles defining opposing pole faces and a lateral surface therebetween for generating magnetic flux emanating from said lateral surface; (b) providing a Hall effect sensor which generates an output voltage signal in response to a change in magnetic flux density emanating from said lateral surface resulting from the proximity or absence of said tooth or notch to one of said pole faces; and (c) attaching said sensor to said lateral surface of the magnet so as to be substantially response to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor.
Claim 50
Dependent Claim
140 words
A magnetic flux responsive proximity sensory assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet comprising: a permanent magnet of predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface therebetween and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means, having at least one sensing plane disposed substantially perpendicular to said magnetic axis, for sensing magnetic flux emanating from said lateral surface resulting from the presence or absence of said metallic body to one of said pole faces; wherein said sensor means is attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor means.
Claim 51
Dependent Claim
140 words
A magnetic flux responsive proximity sensory assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet comprising: a permanent magnet of predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface therebetween and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means, having at least one sensing plane disposed substantially perpendicular to said magnetic axis, for sensing magnetic flux emanating from said lateral surface resulting from the presence or absence of said metallic body to one of said pole faces; wherein said sensor means is attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor means.
Claim 52
Dependent Claim
18 words
The assembly of claim 44 wherein said sensor means includes means for sensing magnetic flux of one polarity.
Claim 53
Dependent Claim
16 words
The assembly of claim 44 wherein said sensor means includes means for sensing bipolar magnetic flux.
Claim 54
Dependent Claim
13 words
The assembly of claim 44 wherein said sensor means includes a reed switch.
Claim 55
Dependent Claim
14 words
The assembly of claim 44 wherein said sensor means includes a magnetic leaf switch.
Claim 56
Dependent Claim
15 words
The assembly of claim 44 wherein said sensor means includes a magnetic axial contact switch.
Claim 57
Dependent Claim
14 words
The assembly of claim 44 wherein said sensor means includes a magneto resistance sensor.
Claim 58
Dependent Claim
15 words
The assembly of claim 44 wherein said sensor means includes a magnetically variable resistive element.
Claim 59
Dependent Claim
22 words
The assembly of claim 51 wherein said sensing plane is parallel to an internal magnetization plane of said magnetically variable resistive element.
Claim 60
Dependent Claim
28 words
The assembly of claim 44 wherein said sensing plane is parallel to radial components of the magnetic flux density emanating from a magnetic surface intermediate said pole faces.
Claim 61
Dependent Claim
154 words
A ferrous body proximity sensor assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet comprising: a magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means having a sensing plane for sensing magnetic flux applied to said sensing plane and producing an output voltage signal as a function of the magnetic flux applied to said sensing plane emanating from said lateral surface resulting from the presence or absence of said metallic body to one of said pole faces; said sensor means attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor means.
Claim 62
Dependent Claim
154 words
A ferrous body proximity sensor assembly adapted to sense the presence or absence of a metallic body disposed adjacent one pole face of a magnet comprising: a magnet of a predetermined cross-section having a North pole and a South pole defining opposing pole faces, a lateral surface intermediate the pole faces and a magnetic axis connecting said opposing pole faces for providing magnetic flux emanating from said lateral surface; and sensor means having a sensing plane for sensing magnetic flux applied to said sensing plane and producing an output voltage signal as a function of the magnetic flux applied to said sensing plane emanating from said lateral surface resulting from the presence or absence of said metallic body to one of said pole faces; said sensor means attached to said lateral surface to be substantially responsive to said flux emanating from said lateral surface to substantially reduce the temperature sensitivity of said sensor means.
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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) | 1993-11-12 | 1994-05-14 | 1994-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-12 | 1998-05-14 | 1998-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-12 | 2002-05-14 | 2002-11-13 | $7700.00 | Window Closed / Lapsed |