US5238095A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hysteresis brakes and clutches
Assignee: Individual
•
Filing: 1992-06-30
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Granted: 1993-08-24
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Expires: 2012-06-30
Abstract
Abstract Improved hysteresis brakes and clutches are disclosed wherein a secondary magnet is so positioned as to establish a substantially unidirectional magnetic field in the annual gap through which the disk or drag cup rotates in order to reduce or eliminate the undesirable phenomenon of "cogging".
Inventors
- 👤 Jeffrey C. Pedu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:58
CPC Classifications
H; H02; H02K; H02K49/00; H02K49/06; H02K49/065
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
116 words
A hysteresis brake or clutch apparatus comprising in combination: a rotatable shaft; a disk coupled to said shaft and projecting radially therefrom, said disk comprising a first portion comprising a magnetic material; a primary magnet comprising a plurality of north-south poles and defining an annular region between said poles, said primary magnet being disposed about said shaft so that said first portion of said disk rotates past said poles and through the magnetic field of said primary magnet when said shaft rotates; and a secondary magnet disposed about said shaft so that said first portion of said disk rotates past said secondary magnet and through the magnetic field of said secondary magnet when said shaft rotates.
Claim 2
Dependent Claim
116 words
A hysteresis brake or clutch apparatus comprising in combination: a rotatable shaft; a disk coupled to said shaft and projecting radially therefrom, said disk comprising a first portion comprising a magnetic material; a primary magnet comprising a plurality of north-south poles and defining an annular region between said poles, said primary magnet being disposed about said shaft so that said first portion of said disk rotates past said poles and through the magnetic field of said primary magnet when said shaft rotates; and a secondary magnet disposed about said shaft so that said first portion of said disk rotates past said secondary magnet and through the magnetic field of said secondary magnet when said shaft rotates.
Claim 3
Dependent Claim
24 words
Apparatus according to claim 1 wherein said secondary magnet is so disposed as to establish a substantially unidirectional magnetic field in said annular region.
Claim 4
Dependent Claim
12 words
Apparatus according to claim 2 wherein said primary magnet is an electromagnet.
Claim 5
Dependent Claim
28 words
Apparatus according to claim 3, wherein said disk comprises a disk portion and a flange portion, and further wherein said first portion is located on said flange portion.
Claim 6
Dependent Claim
79 words
Apparatus according to claim 4 wherein said primary magnet comprises an inner ring-like magnetic member and an outer ring-like magnetic member disposed in a spaced, concentric, cylindrical configuration with respect to each other thereby defining said annular region; and further wherein the outer circumference of said inner magnetic member and the inner circumference of said outer magnetic member comprise a plurality of equal-sized, evenly-spaced slots defining a plurality of north-south poles respectively around the circumferences of said magnetic members.
Claim 7
Dependent Claim
30 words
Apparatus according to claim 5 wherein said secondary magnet is positioned along the inner circumference of said outer magnetic member with its poles facing and adjacent to said annular region.
Claim 8
Dependent Claim
28 words
Apparatus according to claim 6 further wherein the outer circumference of said inner magnetic member comprises two longitudinal slots respectively adjacent the two poles of said secondary magnet.
Claim 9
Dependent Claim
25 words
Apparatus according to claim 7 wherein each of said longitudinal slots encompasses two adjacent equal-sized, evenly-spaced slots along the circumference of said inner magnetic member.
Claim 10
Dependent Claim
16 words
Apparatus according to claim 8 wherein each of said equal-sized, evenly-spaced slots is semicircular in configuration.
Claim 11
Dependent Claim
30 words
Apparatus according to claim 5 wherein said secondary magnet is positioned along the outer circumference of said inner magnetic member with its poles facing and adjacent to said annular region.
Claim 12
Dependent Claim
28 words
Apparatus according to claim 10 further wherein the inner circumference of said outer magnetic member comprises two longitudinal slots respectively adjacent the two poles of said secondary magnet.
Claim 13
Dependent Claim
25 words
Apparatus according to claim 11 wherein each of said longitudinal slots encompasses two adjacent equal-sized, evenly-spaced slots along the circumference of said outer magnetic member.
Claim 14
Dependent Claim
16 words
Apparatus according to claim 12 wherein each of said equal-sized, evenly-spaced slots is semicircular in configuration.
Claim 15
Dependent Claim
12 words
Apparatus according to claim 1 wherein said secondary magnet is an electromagnet.
Claim 16
Dependent Claim
13 words
Apparatus according to claim 1 wherein said secondary magnet is a permanent magnet.
Claim 17
Dependent Claim
20 words
Apparatus according to claim 1 further comprising a non-magnetic shield member surrounding of least a portion of said secondary magnet.
Claim 18
Dependent Claim
13 words
Apparatus according to claim 1 wherein said magnetic material comprises magnetically semi-hard material.
Claim 19
Dependent Claim
129 words
In a brake or clutch apparatus comprising a shaft, a radially-extending disk affixed to said shaft, said disk comprising a first portion comprising a magnetic material, a primary magnet assembly surrounding said shaft and comprising north and south poles on opposite sides of said first portion of said disk, and means for rotatably supporting said shaft for rotation on its axis relative to said primary magnet assembly so that said first portion of said disk rotates past said poles and through the magnetic field of said primary magnet when said shaft rotates; the improvement which comprises a secondary magnet positioned about said shaft so that said first portion of said disk rotates past said secondary magnet and through the magnetic field of said secondary magnet when said shaft rotates.
Claim 20
Dependent Claim
129 words
In a brake or clutch apparatus comprising a shaft, a radially-extending disk affixed to said shaft, said disk comprising a first portion comprising a magnetic material, a primary magnet assembly surrounding said shaft and comprising north and south poles on opposite sides of said first portion of said disk, and means for rotatably supporting said shaft for rotation on its axis relative to said primary magnet assembly so that said first portion of said disk rotates past said poles and through the magnetic field of said primary magnet when said shaft rotates; the improvement which comprises a secondary magnet positioned about said shaft so that said first portion of said disk rotates past said secondary magnet and through the magnetic field of said secondary magnet when said shaft rotates.
Claim 21
Dependent Claim
13 words
Apparatus according to claim 18 wherein said magnetic material comprises magnetically semi-hard material.
Claim 22
Independent Claim
148 words
A method for substantially eliminating cogging in a hysteresis brake and clutch apparatus of the sort which comprises a shaft, a radially-extending disk affixed to said shaft, said disk comprising a first portion comprising a magnetic material, a primary magnet assembly surrounding said shaft and comprising north and south poles on opposite sides of said first portion of said disk, and means for rotatably supporting said shaft for rotation on its axis relative to said primary magnet assembly so that said first portion of said disk rotates past said poles and through the magnetic field of said primary magnet when said shaft rotates, said method comprising: positioning a secondary magnet about said shaft so that said first portion of said disk rotates past said secondary magnet and through the magnetic field of said secondary magnet when said shaft rotates; and turning said disk at lest one complete revolution.
Claim 23
Independent Claim
148 words
A method for substantially eliminating cogging in a hysteresis brake and clutch apparatus of the sort which comprises a shaft, a radially-extending disk affixed to said shaft, said disk comprising a first portion comprising a magnetic material, a primary magnet assembly surrounding said shaft and comprising north and south poles on opposite sides of said first portion of said disk, and means for rotatably supporting said shaft for rotation on its axis relative to said primary magnet assembly so that said first portion of said disk rotates past said poles and through the magnetic field of said primary magnet when said shaft rotates, said method comprising: positioning a secondary magnet about said shaft so that said first portion of said disk rotates past said secondary magnet and through the magnetic field of said secondary magnet when said shaft rotates; and turning said disk at lest one complete revolution.
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) | 1996-08-23 | 1997-02-22 | 1997-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-23 | 2001-02-22 | 2001-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-23 | 2005-02-22 | 2005-08-24 | $7700.00 | Window Closed / Lapsed |