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US5982074A Expired / Lapsed US ⏱️ 0.0 years remaining

Axial field motor/generator

Assignee: Smith Tech Development LLC
•
Filing: 1996-12-11
•
Granted: 1999-11-09
•
Expires: 2016-12-11
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Abstract

Abstract An axial field motor/generator having a rotor that includes at least three annular discs magnetized to provide multiple sector-shaped poles. Each sector has a polarity opposite that of an adjacent sector, and each sector is polarized through the thickness of the disc. The poles of each magnet are aligned with opposite poles of each adjacent magnet. Metal members adjacent the outermost two magnets contain the flux. The motor/generator also has a stator that includes a stator assembly between each two adjacent magnets. Each stator assembly includes one or more conductors or windings. Although the conductors may be formed of wire having a round, uniform cross-section, they may alternatively be formed of conductors having a tapered cross-section that corresponds to the taper of the sectors in order to maximize the density of the conductor in the gap between axially adjacent poles. The conductors may also alternatively be formed of traces in a printed circuit, which may have one or more layers. Each stator assembly may be removably connectable to another stator assembly to provide modularity in manufacturing and to facilitate selection of the voltage at which the motor/generator is to operate. Electrical contacts, such as pins extending from the casing, may removably connect the conductors of adjacent stator assemblies. A magnet may be dynamically balanced on the shaft by hardening a thin ring of cross-linked resin between the magnet and the shaft while the shaft is spun, using ultraviolet light to polymerize the resin.

Inventors

  • 👤 Stephen H. Smith
  • 👤 Yuval Shenkal

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 18:57
CPC Classifications
H; H02; H02K; H02K3/00; H02K3/04; H02K3/26; B; B60; B60L; B60L1/00; B60L1/02; B60L15/00; B60L15/20; B60L3/00; B60L3/0023; B60L3/0061; H02K15/00; H02K15/02; H02K15/03; H02K15/16; H02K15/165; H02K21/00; H02K21/12; H02K21/24; H02K3/28; H02K3/46; H02K3/47; B60L2200/00; B60L2200/36; B60L2220/00; B60L2220/10; B60L2220/16; B60L2220/40; B60L2220/44; B60L2240/00; B60L2240/10; B60L2240/36; B60L2240/40; B60L2240/42; B60L2240/421; B60L2240/423; B60L2270/00; B60L2270/10; B60L2270/14; B60L2270/145; H02K1/00; H02K1/02; H02K1/06; H02K1/22; H02K1/27; H02K16/00; H02K2203/00; H02K2203/03; H02K2203/09; H02K29/00; H02K29/06; H02K29/08; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64; Y02T10/72

Claims Analysis

Total Claims: 52
Claim 1
Independent Claim 327 words
A motor/generator, comprising: a stator having an axis and at least two layers spaced along said axis, each layer including a conductor phase assembly with a winding having an elongated conductor portion oriented in a generally radial direction with respect to said axis; a rotor having an axis coaxial with said axis of said stator, said rotor comprising: a shaft rotatably coupled to said stator; at least three annular magnets including two annular outer magnets and at least one annular center magnet; said two annular outer magnets coaxially coupled to said shaft, each outer magnet having a permeability, an axis, first and second faces and a plurality of contiguous sector-shaped poles, an axial distance between said faces defining a thickness, each pole of said first face being of opposite polarity from an angularly adjacent pole of said first face and of opposite polarity from an axially adjacent pole of said second face; said annular center magnet coaxially coupled to said shaft between said outer magnets, each center magnet having a permeability, an axis, first and second faces and a plurality of contiguous sector-shaped poles, an axial distance between said faces defining a thickness, each pole of said first face being of opposite polarity from an angularly adjacent pole of said first face and of opposite polarity from an axially adjacent pole of said second face; and one of said first and second faces of each sector of each magnet having a pole fixedly aligned with a pole of an adjacent magnet having opposite polarity; and said thicknesses of said magnets being substantially equal, each magnet being axially spaced from an adjacent magnet by a gap spacing approximately equal to said thickness, said winding of each of said layers of said stator being disposed between axially spaced adjacent magnets; and two endcaps, each having a permeability greater than said permeability of said outer magnets and disposed adjacent one of said first and second faces of an outer magnet.
Claim 2
Dependent Claim 327 words
A motor/generator, comprising: a stator having an axis and at least two layers spaced along said axis, each layer including a conductor phase assembly with a winding having an elongated conductor portion oriented in a generally radial direction with respect to said axis; a rotor having an axis coaxial with said axis of said stator, said rotor comprising: a shaft rotatably coupled to said stator; at least three annular magnets including two annular outer magnets and at least one annular center magnet; said two annular outer magnets coaxially coupled to said shaft, each outer magnet having a permeability, an axis, first and second faces and a plurality of contiguous sector-shaped poles, an axial distance between said faces defining a thickness, each pole of said first face being of opposite polarity from an angularly adjacent pole of said first face and of opposite polarity from an axially adjacent pole of said second face; said annular center magnet coaxially coupled to said shaft between said outer magnets, each center magnet having a permeability, an axis, first and second faces and a plurality of contiguous sector-shaped poles, an axial distance between said faces defining a thickness, each pole of said first face being of opposite polarity from an angularly adjacent pole of said first face and of opposite polarity from an axially adjacent pole of said second face; and one of said first and second faces of each sector of each magnet having a pole fixedly aligned with a pole of an adjacent magnet having opposite polarity; and said thicknesses of said magnets being substantially equal, each magnet being axially spaced from an adjacent magnet by a gap spacing approximately equal to said thickness, said winding of each of said layers of said stator being disposed between axially spaced adjacent magnets; and two endcaps, each having a permeability greater than said permeability of said outer magnets and disposed adjacent one of said first and second faces of an outer magnet.
Claim 3
Dependent Claim 26 words
The motor/generator recited in claim 1, wherein each said conductor phase assembly comprises a plurality of planar windings angularly distributed around said axis of said stator.
Claim 4
Dependent Claim 37 words
The motor/generator recited in claim 2, wherein each winding has exactly two said elongated conductor portions, said elongated conductor portions angularly spaced from one another by an angular spacing equal to an angular spacing of said poles.
Claim 5
Dependent Claim 25 words
The motor/generator recited in claim 1, wherein said permeability of each outer and central magnet is no more than 100 times the permeability of air.
Claim 6
Dependent Claim 15 words
The motor/generator recited in claim 1, wherein each magnet is made of a ferroceramic material.
Claim 7
Dependent Claim 43 words
The motor/generator recited in claim 1, wherein said plurality of contiguous sector-shaped poles of each magnet is selected in number to prevent operation beyond a knee of a characteristic B-H curve of said magnet when said magnet is magnetically isolated from other magnets.
Claim 8
Dependent Claim 85 words
The motor/generator recited in claim 1, wherein: each said magnet has an opening with a circumference, and each said sector has an inside length along a portion of said circumference of said opening; each said magnet has a transition area between poles of angularly adjacent sectors, said transition area has a transition width, and each layer of said stator includes a number of said conductor phase assemblies essentially equal to said inside length divided by said transition width and multiplied by the number of sectors.
Claim 9
Dependent Claim 21 words
The motor/generator recited in claim 1, wherein said elongated conductor portion of each conductor phase assembly has a tapering cross-sectional area.
Claim 10
Dependent Claim 17 words
The motor/generator recited in claim 8, wherein said motor/generator has a fill factor greater than 80 percent.
Claim 11
Dependent Claim 17 words
The motor/generator recited in claim 8, wherein each said elongated conductor portion has a rectangular cross-sectional shape.
Claim 12
Dependent Claim 16 words
The motor/generator recited in claim 1, wherein each elongated conductor portion has a round cross-sectional shape.
Claim 13
Dependent Claim 34 words
The motor/generator recited in claim 1, wherein each said layer of said stator comprises a plurality of laminations, each having a planar substrate, and said winding comprises a metallic layer bonded to said substrate.
Claim 14
Dependent Claim 22 words
The motor/generator recited in claim 12, wherein said substrate is made of sheet-like plastic having a thickness less than about 0.025 inches.
Claim 15
Dependent Claim 21 words
The motor/generator recited in claim 13, wherein said winding comprises a metallic layer having a thickness less than about 0.005 inches.
Claim 16
Dependent Claim 23 words
The motor/generator recited in claim 1, wherein each said layer of said stator comprises a casing having said conductor phase assembly enclosed therein.
Claim 17
Dependent Claim 17 words
The motor/generator recited in claim 15, wherein each said casing is removably connectable to an adjacent casing.
Claim 18
Dependent Claim 25 words
The motor/generator recited in claim 16, further comprising a pin extending between adjacent casings and electrically connecting said conductor phase assemblies of said adjacent casings.
Claim 19
Dependent Claim 20 words
The motor/generator recited in claim 1, wherein said motor/generator operates at an efficiency of between 88 percent and 99 percent.
Claim 20
Dependent Claim 15 words
The motor/generator recited in claim 18, wherein each magnet is made of a ferroceramic material.
Claim 21
Dependent Claim 19 words
The motor/generator recited in claim 1, wherein said motor/generator has a power-to-weight ratio between about 0.1 to 1.0 HP/lb.
Claim 22
Dependent Claim 15 words
The motor/generator recited in claim 20, wherein each magnet is made of a ferroceramic material.
Claim 23
Dependent Claim 33 words
The motor/generator recited in claim 1, wherein said plurality of contiguous sector-shaped poles of each annular magnet is equal in number to said plurality of contiguous sector-shaped poles of each other annular magnet.
Claim 24
Dependent Claim 28 words
The motor/generator recited in claim 1, wherein each sector-shaped pole of each annular magnet is the same size as each other sector-shaped pole of each other annular magnet.
Claim 25
Dependent Claim 45 words
The motor/generator recited in claim 1, wherein said rotor has a number of said annular magnets and said stator has a number of said layers, and said number of annular magnets of said rotor exceeds said number of layers of said stator by exactly one.
Claim 26
Dependent Claim 24 words
The motor/generator recited in claim 1, wherein each annular magnet is made of a material having the same permeability as each other annular magnet.
Claim 27
Dependent Claim 93 words
A motor/generator, comprising: a stator having an axis and a plurality of layers spaced along said axis; and a rotor having an axis coaxial with said stator, said rotor comprising a shaft rotatably coupled to said stator and having a plurality of annular magnets producing magnetic fields distributed around said rotor at a plurality of angular positions, each field extending axially across at least one of said layers, a first one of said magnets having a thickness and axially spaced from an adjacent magnet by a gap spacing approximately equal to said thickness.
Claim 28
Dependent Claim 93 words
A motor/generator, comprising: a stator having an axis and a plurality of layers spaced along said axis; and a rotor having an axis coaxial with said stator, said rotor comprising a shaft rotatably coupled to said stator and having a plurality of annular magnets producing magnetic fields distributed around said rotor at a plurality of angular positions, each field extending axially across at least one of said layers, a first one of said magnets having a thickness and axially spaced from an adjacent magnet by a gap spacing approximately equal to said thickness.
Claim 29
Dependent Claim 22 words
The motor/generator recited in claim 26, wherein each magnetic field is essentially confined within an axially oriented region having a sector-shaped cross-section.
Claim 30
Dependent Claim 16 words
The motor/generator recited in claim 27, wherein each layer comprises a plurality of conductor phase assemblies.
Claim 31
Dependent Claim 15 words
The motor/generator recited in claim 27, wherein each layer comprises a plurality of planar windings.
Claim 32
Dependent Claim 34 words
The motor/generator recited in claim 26, wherein each of said annular magnets has a plurality of contiguous sector-shaped poles equal in number to said plurality of contiguous sector-shaped poles of each other annular magnet.
Claim 33
Dependent Claim 33 words
The motor/generator recited in claim 26, wherein each of said annular magnets has a plurality of contiguous sector-shaped poles, each the same size as each other sector-shaped pole of each other annular magnet.
Claim 34
Dependent Claim 45 words
The motor/generator recited in claim 26, wherein said rotor has a number of said annular magnets and said stator has a number of said layers, and said number of annular magnets of said rotor exceeds said number of layers of said stator by exactly one.
Claim 35
Dependent Claim 28 words
The motor/generator recited in claim 26, wherein each annular magnet has a permeability and is made of a material having the same permeability as each other annular magnet.
Claim 36
Dependent Claim 54 words
The motor/generator recited in claim 26, wherein: each annular magnet has a plurality of sector-shaped poles; each layer of said stator has a winding with exactly two elongated conductor portions; and each elongated conductor portion is spaced from another elongated conductor portion by an angular spacing equal to an angular spacing of said poles.
Claim 37
Dependent Claim 22 words
The motor/generator recited in claim 26, wherein each annular magnet has a permeability no more than 100 times the permeability of air.
Claim 38
Dependent Claim 16 words
The motor/generator recited in claim 26, wherein each annular magnet is made of a ferroceramic material.
Claim 39
Dependent Claim 93 words
The motor/generator recited in claim 26, wherein: each said magnet has a plurality of sector-shaped poles and an opening with a circumference, and each said sector-shaped pole has an inside length along a portion of said circumference of said opening; each said magnet has a transition area between poles of angularly adjacent sectors, said transition area has a transition width, and each layer of said stator includes a number of said conductor phase assemblies essentially equal to said inside length divided by said transition width and multiplied by the number of sector-shaped poles.
Claim 40
Dependent Claim 22 words
The motor/generator recited in claim 26, wherein each layer of said stator has an elongated conductor portion with a tapering cross-sectional area.
Claim 41
Dependent Claim 17 words
The motor/generator recited in claim 38, wherein said motor/generator has a fill factor greater than 80 percent.
Claim 42
Dependent Claim 17 words
The motor/generator recited in claim 38, wherein each said elongated conductor portion has a rectangular cross-sectional shape.
Claim 43
Dependent Claim 39 words
The motor/generator recited in claim 26, wherein each said layer of said stator has a winding and comprises a plurality of laminations, each lamination having a planar substrate, and said winding comprises a metallic layer bonded to said substrate.
Claim 44
Dependent Claim 22 words
The motor/generator recited in claim 41, wherein said substrate is made of sheet-like plastic having a thickness less than about 0.025 inches.
Claim 45
Dependent Claim 21 words
The motor/generator recited in claim 42, wherein said winding comprises a metallic layer having a thickness less than about 0.005 inches.
Claim 46
Dependent Claim 25 words
The motor/generator recited in claim 26, wherein each said layer of said stator comprises a casing and a conductor phase assembly enclosed in said casing.
Claim 47
Dependent Claim 17 words
The motor/generator recited in claim 44, wherein each said casing is removably connectable to an adjacent casing.
Claim 48
Dependent Claim 25 words
The motor/generator recited in claim 45, further comprising a pin extending between adjacent casings and electrically connecting said conductor phase assemblies of said adjacent casings.
Claim 49
Dependent Claim 19 words
The motor/generatorrecited in claim 26, wherein said motor/generator operates at an efficiency of between 88 percent and 99 percent.
Claim 50
Dependent Claim 18 words
The motor/generatorrecited in claim 26, wherein said motor/generator has a power-to-weight ratio between about 0.1 to 1.0 HP/lb.
Claim 51
Dependent Claim 136 words
A motor/generator, comprising: a stator having an axis and a plurality of layers spaced along said axis; and a rotor having an axis coaxial with said stator, said rotor comprising a shaft rotatably coupled to said stator and having a plurality of annular magnets producing magnetic fields distributed around said rotor at a plurality of angular positions, each field extending axially across at least one of said layers, each magnet having a thickness substantially equal to said thickness of all other said magnets, each magnet axially spaced from an adjacent magnet by a gap spacing approximately equal to said thickness, said plurality of contiguous sector-shaped poles of each magnet is selected in number to prevent operation beyond a knee of a characteristic B-H curve of said magnet when said magnet is magnetically isolated from other magnets.
Claim 52
Dependent Claim 136 words
A motor/generator, comprising: a stator having an axis and a plurality of layers spaced along said axis; and a rotor having an axis coaxial with said stator, said rotor comprising a shaft rotatably coupled to said stator and having a plurality of annular magnets producing magnetic fields distributed around said rotor at a plurality of angular positions, each field extending axially across at least one of said layers, each magnet having a thickness substantially equal to said thickness of all other said magnets, each magnet axially spaced from an adjacent magnet by a gap spacing approximately equal to said thickness, said plurality of contiguous sector-shaped poles of each magnet is selected in number to prevent operation beyond a knee of a characteristic B-H curve of said magnet when said magnet is magnetically isolated from other magnets.

References Cited (Backward Citations)

US2734140A Cited
US27187A Cited
US1144012A Cited
US1726232A Cited
US1863294A Cited
US1829686A Cited
US2073532A Cited
US2151146A Cited
US2262376A Cited
US2236436A Cited
US2573494A Cited
US2479589A Cited
US2600052A Cited
US2474195A Cited
US3089069A Cited
US2873395A Cited
US2898534A Cited
US2907903A Cited
US3061750A Cited
US3077548A Cited
US3231774A Cited
US3230406A Cited
US3189770A Cited
US3109114A Cited
US3189773A Cited
US3231771A Cited
US3223868A Cited
US3219861A Cited
USRE27187E Cited
US3153184A Cited
US3242363A Cited
US3229137A Cited
US3233133A Cited
US3324321A Cited
US3315106A Cited
US3292024A Cited
US3549928A Cited
US3327191A Cited
US3277323A Cited
US3343014A Cited
US3331973A Cited
US3418506A Cited
US3359476A Cited
US3411059A Cited
US3375386A Cited
US3296475A Cited
US3405296A Cited
US3432707A Cited
US3437854A Cited
US3407320A Cited
US3480815A Cited
US3413503A Cited
US3439205A Cited
US3401323A Cited
US3401284A Cited
US3450909A Cited
US3428840A Cited
US3500095A Cited
US3515922A Cited
US3549918A Cited
US3470409A Cited
US3581389A Cited
US3673477A Cited
US3567978A Cited
US3696277A Cited
US3713015A Cited
US3696260A Cited
US3953751A Cited
US3800175A Cited
US3700944A Cited
US3832581A Cited
US3821602A Cited
US3949253A Cited
US3906267A Cited
US3979619A Cited
US3999092A Cited
US3992641A Cited
US4067732A Cited
US4100444A Cited
US4085355A Cited
US4097758A Cited
US4127799A Cited
US4190780A Cited
US4187441A Cited
GB2090478B Cited
US4243902A Cited
US4390865A Cited
US4371801A Cited
US4242610A Cited
US4262608A Cited
US4295083A Cited
US4341973A Cited
US4445061A Cited
US4358723A Cited
US4490635A Cited
US4424463A Cited
US4358693A Cited
US4425521A Cited
US4484097A Cited
US5304886A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-11-08 2003-05-10 2003-11-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-11-08 2007-05-10 2007-11-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-11-08 2011-05-10 2011-11-09 $7700.00 Window Closed / Lapsed

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