Patent US4755751A successfully refreshed from Google Patents.
US4755751A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brushless rotary position transducer
Assignee: Allen Bradley Co LLC
•
Filing: 1986-12-29
•
Granted: 1988-07-05
•
Expires: 2006-12-29
Abstract
Abstract A brushless resolver has first and second ring-shaped magnetic pole elements spaced from each other along a common axis. An excitation coil is wound axially between the two pole elements. First and second output coils are wound through the first and second pole elements and spaced radially from each other. A rotor is within the pole elements and has a shaft extending along the axis. First and second magnetic coupling elements are spaced along the shaft each of which being coplanar with a different one of the pole elements. Each coupling element providing 180 degrees of magnetic coupling with respect to the corresponding pole element. A high frequency signal applied to the excitations coil is transformer coupled to the output signals. The degree of coupling varies with the position of the coupling elements. The demodulated signal from each of the output coils has a triangular shaped waveform which may be directly differentiated to produce the angular velocity of the rotor shaft.
Inventors
- 👤 Glen Ray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:22
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; H; H02; H02K; H02K24/00
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
114 words
A rotary transducer comprising: first and second ring-shaped magnetic pole elements spaced from each other along a common axis; first and second coils, each being wound through said first and second pole elements and spaced radially around the axis from each other; an excitation coil for producing an alternating magnetic field which polarizes said pole elements; and a rotor within said ring shaped pole elements having a shaft extending along the common axis, and having first and second magnetic coupling elements spaced along the shaft, each of the coupling elements associated with a different one of said pole elements and providing substantially 180 degrees of magnetic coupling with respect to the associated pole element.
Claim 2
Dependent Claim
114 words
A rotary transducer comprising: first and second ring-shaped magnetic pole elements spaced from each other along a common axis; first and second coils, each being wound through said first and second pole elements and spaced radially around the axis from each other; an excitation coil for producing an alternating magnetic field which polarizes said pole elements; and a rotor within said ring shaped pole elements having a shaft extending along the common axis, and having first and second magnetic coupling elements spaced along the shaft, each of the coupling elements associated with a different one of said pole elements and providing substantially 180 degrees of magnetic coupling with respect to the associated pole element.
Claim 3
Dependent Claim
50 words
The transducer as in claim 1 wherein each of the coupling elements has a substantially semi-circular shape, the coupling elements positioned substantially 180 degrees with respect to each other about the shaft; and wherein said first and second coils are spaced substantially 90 degrees from each other around the axis.
Claim 4
Dependent Claim
20 words
The transducer as in claim 1 wherein said excitation coil is wound axially between said first and second pole elements.
Claim 5
Dependent Claim
20 words
The transducer as in claim 1 wherein the first and second coupling elements are coplanar with the corresponding pole element.
Claim 6
Dependent Claim
24 words
The transducer as in claim 4 wherein each of the coupling elements has a substantially semi-circular shape in the plane of said pole element.
Claim 7
Dependent Claim
24 words
The transducer as in claim 1 wherein said first and second coils are spaced radially substantially 45 degrees from each other around the axis.
Claim 8
Dependent Claim
48 words
The transducer as in claim 6 wherein each of the coupling elements comprises: a first portion extending axially from the shaft for substantially 90 degrees around the shaft; and a second portion extending axially from the shaft opposite said first portion for substantially 90 degrees around the shaft.
Claim 9
Dependent Claim
35 words
The transducer as in claim 1 wherein said first and second coils are wound through said pole elements in a manner to produce signals from said coils which are modulated by signals having triangular waveforms.
Claim 10
Dependent Claim
140 words
A rotary transducer comprising: first and second ring-shaped magnetic pole elements spaced from each other along a common axis; an excitation coil for producing a magnetic field which polarizes said pole elements; a rotor, within said pole elements, having a shaft extending along the axis and having separate first and second magnetic coupling elements spaced along said shaft each of the coupling elements associated with one of said pole elements and providing substantially 180 degrees of magnetic coupling with respect to the associated pole element; and first and second output coils each positioned with respect to said first and second pole elements so that a current is induced in each output coil due to the magnetic coupling of said rotor to said pole elements, which current varies with respect to the angular position of the rotor within the pole elements.
Claim 11
Dependent Claim
140 words
A rotary transducer comprising: first and second ring-shaped magnetic pole elements spaced from each other along a common axis; an excitation coil for producing a magnetic field which polarizes said pole elements; a rotor, within said pole elements, having a shaft extending along the axis and having separate first and second magnetic coupling elements spaced along said shaft each of the coupling elements associated with one of said pole elements and providing substantially 180 degrees of magnetic coupling with respect to the associated pole element; and first and second output coils each positioned with respect to said first and second pole elements so that a current is induced in each output coil due to the magnetic coupling of said rotor to said pole elements, which current varies with respect to the angular position of the rotor within the pole elements.
Claim 12
Dependent Claim
21 words
The rotary position transducer as in claim 9 wherein said excitation coil is axially between said first and second pole elements.
Claim 13
Dependent Claim
17 words
The transducer as in claim 9 wherein each of said coupling elements has a substantially semi-circular shape.
Claim 14
Dependent Claim
48 words
The transducer as in claim 9 wherein each of the coupling elements comprises: a first portion extending axially from the shaft for substantially 90 degrees about the shaft; and a second portion extending axially from the shaft opposite said first portion for substantially 90 degrees about the shaft.
Claim 15
Dependent Claim
25 words
The transducer as in claim 9 wherein said output coils are positioned so as to produce signals that are modulated by signals having triangular waveforms.
Claim 16
Dependent Claim
60 words
The transducer as in claim 9 wherein said magnetic pole elements have apertures extending therethrough and said output coils being wound through the apertures in each pole element, the apertures in one of said pole elements being rotated about the axis with respect to the other pole element so that the apertures of the two pole elements are not aligned.
Claim 17
Dependent Claim
128 words
A rotary transducer comprising: first and second ring-shaped magnetic pole elements spaced from each other along a common axis; an excitation coil for producing a magnetic field which polarizes said pole elements; a rotor, within said pole elements, having a shaft extending along the axis and having separate first and second magnetic coupling elements spaced along said shaft each of the coupling elements magnetically coupled to a different one of said pole elements; and first and second output coils each positioned with respect to said first and second pole elements so that a current is induced in each output coil due to the magnetic coupling of said rotor to said pole elements, which current varies with respect to the angular position of the rotor within the pole elements.
Claim 18
Dependent Claim
128 words
A rotary transducer comprising: first and second ring-shaped magnetic pole elements spaced from each other along a common axis; an excitation coil for producing a magnetic field which polarizes said pole elements; a rotor, within said pole elements, having a shaft extending along the axis and having separate first and second magnetic coupling elements spaced along said shaft each of the coupling elements magnetically coupled to a different one of said pole elements; and first and second output coils each positioned with respect to said first and second pole elements so that a current is induced in each output coil due to the magnetic coupling of said rotor to said pole elements, which current varies with respect to the angular position of the rotor within the pole elements.
References Cited (Backward Citations)
US2949576A
Cited
US3819268A
Cited
US4011440A
Cited
US4481468A
Cited
US4449117A
Cited
US4605889A
Cited
US4692699A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-05 | 1992-01-04 | 1992-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-05 | 1996-01-04 | 1996-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-05 | 2000-01-04 | 2000-07-05 | $7700.00 | Window Closed / Lapsed |