US3899699A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brushless linear DC motor actuator
Assignee: International Business Machines Corp
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Filing: 1974-05-28
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Granted: 1975-08-12
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Expires: 1994-05-28
Abstract
Abstract A linear motor actuator employing an elongated magnetic field source such as a permanent magnet includes a bar of ferromagnetic material parallel to but spaced from this magnet with an electrically energizable coil slidably mounted along the bar. The coil and magnetic circuit are arranged so that energization of the coil produces current carrying conductors in the field of the magnetic circuit which imparts force to the movable coil and armature arrangement. The direction of movement of the coil is determined by the polarity of the electrical energy and the orientation of the magnetic field.
Inventors
- 👤 Brandt Mead Griffing
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:31
CPC Classifications
H; H02; H02K; H02K41/00; H02K41/02; H02K41/035; H02K41/0352; H02K41/0354; H02K41/0356; B; B41; B41J; B41J19/00; B41J19/18; B41J19/20; B41J19/30; B41J19/305
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
198 words
A linear actuator comprising a magnetic flux field source having two elongated surfaces with the magnetic flux field being produced perpendicular to said two surfaces, a first bar of ferromagnetic material parallel to but spaced from said magnetic source surfaces for providing a low magnetic reluctance path therebetween, a coil mounted around said first bar for permitting relative motion between said coil and said bar, means movable with said coil and at least partially mounted within said coil for providing a low magnetic reluctance path between said first bar and one of said magnetic flux sources surfaces, said means for providing a low reluctance path from within said coil being attached to said coil and being comprised of a center portion and two arms in a generally U-shaped configuration with said center portion passing through said coil and with the outer ends of said arms terminating in proximity to said one of said magnetic flux source surfaces, and means for applying electrical energy to said coil, whereby a moving force is applied to said coil in a direction determined by the polarity of the said electrical energy and the orientation of the magnetic field polarity from said Source.
Claim 2
Dependent Claim
198 words
A linear actuator comprising a magnetic flux field source having two elongated surfaces with the magnetic flux field being produced perpendicular to said two surfaces, a first bar of ferromagnetic material parallel to but spaced from said magnetic source surfaces for providing a low magnetic reluctance path therebetween, a coil mounted around said first bar for permitting relative motion between said coil and said bar, means movable with said coil and at least partially mounted within said coil for providing a low magnetic reluctance path between said first bar and one of said magnetic flux sources surfaces, said means for providing a low reluctance path from within said coil being attached to said coil and being comprised of a center portion and two arms in a generally U-shaped configuration with said center portion passing through said coil and with the outer ends of said arms terminating in proximity to said one of said magnetic flux source surfaces, and means for applying electrical energy to said coil, whereby a moving force is applied to said coil in a direction determined by the polarity of the said electrical energy and the orientation of the magnetic field polarity from said Source.
Claim 3
Dependent Claim
66 words
The linear actuator as defined in claim 1 wherein said magnetic flux source includes a permanent magnet for producing a magnetic flux field perpendicular to two elongated surfaces thereof, and an arcuate magnetic circuit completing means for transferring the magnetic flux from one of said permanent magnet elongated surfaces to said first bar so as to provide one of said magnetic flux field source elongated surfaces.
Claim 4
Dependent Claim
177 words
A linear actuator comprising a magnetic flux field source having two elongated surfaces with the magnetic flux field being produced perpendicular to said two surfaces, a first bar of ferromagnetic material parallel to but spaced from said magnetic source surfaces for providing a low magnetic reluctance path therebetween, said first bar of ferromagnetic material being comprised of a plurality of elements arranged in a laminated configuration with said elements being oriented substantially perpendicular to said two surfaces, whereby the longitudinal reluctance of said first bar is increased, a coil mounted around said first bar for permitting relative motion between said coil and said bar, means movable with said coil and at least partially mounted within said coil for providing a low magnetic reluctance path between said first bar and one of said magnetic flux source surfaces, and means for applying electrical energy to said coil, whereby a moving force is applied to said coil in a direction determined by the polarity of the said electrical energy and the orientation of the magnetic field polarity from said source.
Claim 5
Dependent Claim
177 words
A linear actuator comprising a magnetic flux field source having two elongated surfaces with the magnetic flux field being produced perpendicular to said two surfaces, a first bar of ferromagnetic material parallel to but spaced from said magnetic source surfaces for providing a low magnetic reluctance path therebetween, said first bar of ferromagnetic material being comprised of a plurality of elements arranged in a laminated configuration with said elements being oriented substantially perpendicular to said two surfaces, whereby the longitudinal reluctance of said first bar is increased, a coil mounted around said first bar for permitting relative motion between said coil and said bar, means movable with said coil and at least partially mounted within said coil for providing a low magnetic reluctance path between said first bar and one of said magnetic flux source surfaces, and means for applying electrical energy to said coil, whereby a moving force is applied to said coil in a direction determined by the polarity of the said electrical energy and the orientation of the magnetic field polarity from said source.
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) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |