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US5039894A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetostrictive linear motor

Assignee: United States Department of the Navy
•
Filing: 1990-10-11
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Granted: 1991-08-13
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Expires: 2010-10-11
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Abstract

Abstract The magnetostrictive rod of a linear motor is made of twinned single crys Terfenol-D having its crystalline axis aligned with the rod axis to produce non-uniform transverse magnetostriction during axial magnetostrictive elongation of the rod in response to a triggering magnetic field. Slide bearing forces applied through spring biased support plates are limited to flat surfaces formed on the rod perpendicular to a transverse axis along which the rod is magnetostrictively contracted.

Inventors

  • 👤 Joseph P. Teter
  • 👤 Arthur E. Clark

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 14:56
CPC Classifications
H; H10; H10N; H10N35/00

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 117 words
In a motor having a stator, an active element under compressive stress of bearing forces accompanying frictional sliding contact therewith and means applying a magnetic field for magnetostrictive elongation of the active element in an axial direction and transverse magnetostriction under said compressive stress, the improvement residing in said active element being made of a magnetostrictive material with properties rendering said transverse magnetostriction non-uniform about said axial direction, said stator including support means for limiting said frictional sliding contact to a preferential location on the active element at which the transverse magnetostriction is negative and prestressed means for regulating reduction in the bearing forces exerted at said preferential location during said magnetostrictive elongation of the active element.
Claim 2
Dependent Claim 117 words
In a motor having a stator, an active element under compressive stress of bearing forces accompanying frictional sliding contact therewith and means applying a magnetic field for magnetostrictive elongation of the active element in an axial direction and transverse magnetostriction under said compressive stress, the improvement residing in said active element being made of a magnetostrictive material with properties rendering said transverse magnetostriction non-uniform about said axial direction, said stator including support means for limiting said frictional sliding contact to a preferential location on the active element at which the transverse magnetostriction is negative and prestressed means for regulating reduction in the bearing forces exerted at said preferential location during said magnetostrictive elongation of the active element.
Claim 3
Dependent Claim 26 words
The improvement as defined in claim 1 wherein said magnetostrictive material is twinned single crystal Terfenol-D having a crystalline axis substantially aligned with said axial direction.
Claim 4
Dependent Claim 31 words
The improvement as defined in claim 2 wherein said transverse magnetostriction varies between maximum contraction at the preferential location on the active element and expansion at other locations angularly spaced therefrom.
Claim 5
Dependent Claim 37 words
The improvement as defined in claim 1 wherein said support means includes a bearing plate having a planar surface on which said sliding frictional contact is established at the preferential location under bias of the prestressed means.
Claim 6
Dependent Claim 31 words
The improvement as defined in claim 4 wherein said transverse magnetostriction varies between maximum contraction at the preferential location on the active element and expansion at other locations angularly spaced therefrom.
Claim 7
Dependent Claim 31 words
The improvement as defined in claim 1 wherein said transverse magnetostriction varies between maximum contraction at the preferential location on the active element and expansion at other locations angularly spaced therefrom.
Claim 8
Dependent Claim 115 words
In a motor having a stator, an active element under compressive stress of bearing forces accompanying frictional sliding contact therewith and means applying a magnetic field for magnetostrictive elongation of the active element in an axial direction and transverse magnetostriction under said compressive stress, the improvement residing in said active element being made of twinned single crystal Terfenol-D having a crystalline axis substantially aligned with said axial direction and said stator including support means for limiting said frictional sliding contact to a preferential location on the active element at which the transverse magnetostriction is negative and prestressed means engageable with the support means for regulating reduction in the bearing forces exerted at said preferential location.
Claim 9
Dependent Claim 115 words
In a motor having a stator, an active element under compressive stress of bearing forces accompanying frictional sliding contact therewith and means applying a magnetic field for magnetostrictive elongation of the active element in an axial direction and transverse magnetostriction under said compressive stress, the improvement residing in said active element being made of twinned single crystal Terfenol-D having a crystalline axis substantially aligned with said axial direction and said stator including support means for limiting said frictional sliding contact to a preferential location on the active element at which the transverse magnetostriction is negative and prestressed means engageable with the support means for regulating reduction in the bearing forces exerted at said preferential location.
Claim 10
Dependent Claim 39 words
The improvement as defined in claim 7 wherein said transverse magnetostriction varies between said negative at the preferential location on the active element and positive transverse magnetostriction at locations unencumbered by said forces angularly spaced from the preferential location.
Claim 11
Dependent Claim 31 words
The improvement as defined in claim 7 wherein said support means includes a bearing plate having a planar surface on which said sliding frictional contact is established at the preferential location.
Claim 12
Dependent Claim 84 words
In a motor having an active element under stress accompanying frictional sliding contact therewith and means applying a magnetic field for magnetostrictive elongation of the active element and magnetostriction transverse to said elongation, the improvement residing in said active element being made of a magnetostrictive material with properties rendering said magnetostriction transverse to the elongation non-uniform, and prestressed means acting on the active element through said sliding contact for controllably maintaining the active element under said stress transverse to and during said elongation thereof.
Claim 13
Dependent Claim 84 words
In a motor having an active element under stress accompanying frictional sliding contact therewith and means applying a magnetic field for magnetostrictive elongation of the active element and magnetostriction transverse to said elongation, the improvement residing in said active element being made of a magnetostrictive material with properties rendering said magnetostriction transverse to the elongation non-uniform, and prestressed means acting on the active element through said sliding contact for controllably maintaining the active element under said stress transverse to and during said elongation thereof.
Claim 14
Dependent Claim 26 words
The improvement as defined in claim 10 wherein said magnetostrictive material is twinned single crystal Terfenol-D having a crystalline axis substantially aligned with said axial direction.
Claim 15
Dependent Claim 19 words
The improvement as defined in claim 10 wherein said transverse magnetostriction varies between maximum negative contraction and maximum expansion.
Claim 16
Dependent Claim 65 words
In a motor having an active element and means applying magnetic field for magnetostrictive elongation and transverse deformation of the active element, said magnetostrictive transverse deformation varying between maximum contraction and maximum expansion, and prestressed means for controllably maintaining the active element under stress exerted transversely on the active element only at locations thereon at which the maximum contraction of the magnetostrictive transverse deformation occurs.
Claim 17
Dependent Claim 65 words
In a motor having an active element and means applying magnetic field for magnetostrictive elongation and transverse deformation of the active element, said magnetostrictive transverse deformation varying between maximum contraction and maximum expansion, and prestressed means for controllably maintaining the active element under stress exerted transversely on the active element only at locations thereon at which the maximum contraction of the magnetostrictive transverse deformation occurs.
Claim 18
Dependent Claim 26 words
The improvement as defined in claim 13 wherein said magnetostrictive material is twinned single crystal Terfenol-D having a crystalline axis along which said magnetostrictive elongation occurs.
Claim 19
Dependent Claim 59 words
In a motor having a stator, a magnetostrictive element having flat bearing surfaces in slide bearing contact with the stator and coil means for applying a magnetic field orientated substantially parallel to said flat bearing surfaces of the element, the element being made of twinned single crystal Terfenol-D having a crystalline axis substantially parallel to said flat bearing surfaces.
Claim 20
Dependent Claim 59 words
In a motor having a stator, a magnetostrictive element having flat bearing surfaces in slide bearing contact with the stator and coil means for applying a magnetic field orientated substantially parallel to said flat bearing surfaces of the element, the element being made of twinned single crystal Terfenol-D having a crystalline axis substantially parallel to said flat bearing surfaces.
Claim 21
Dependent Claim 26 words
The combination of claim 15 wherein said stator includes spring biased means for limiting said slide bearing contact to the flat bearing surfaces of the element.

References Cited (Backward Citations)

US2105479A Cited
GB796221A Cited
US3304479A Cited
US3439199A Cited
US3419739A Cited
US3634742A Cited
US4017754A Cited
US4831290A Cited
US4927334A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-08-12 1995-02-11 1995-08-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-08-12 1999-02-11 1999-08-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-08-12 2003-02-11 2003-08-13 $7700.00 Window Closed / Lapsed

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