US4883994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Linear motor
Assignee: Sony Corp
•
Filing: 1988-01-29
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Granted: 1989-11-28
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Expires: 2008-01-29
Abstract
Abstract A linear motor comprises a first yoke (19), a second yoke (20) spaced by a first gap (25) from the first yoke (19), a current-carrying coil (21) surrounding at least one of the first yoke (19) and the second yoke (20), and a magnet (14) spaced by a second gap (27) from the first and second yokes (19, 20). An end portion of the magnet (14) extends over the first gap (25) when the magnet (14) is in an end or starting position.
Inventors
- 👤 Hideo Nikura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:23
CPC Classifications
H; H02; H02K; H02K41/00; H02K41/02; H02K41/035; H02K41/0352
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
135 words
A linear motor comprising: a first yoke and a second yoke spaced apart the width of a first gap from each other; a magnet spaced apart the width of a second gap from and arranged in opposed relation to said first yoke and second yoke; a coil fixed to the end of said magnet through a nonmagnetic material; a third yoke and a fourth yoke spaced apart the same width of a gap as that of said first gap from each other and so arranged in opposed relation to said magnet as to be spaced apart the same width of a gap as that of said second gap from said magnet; and a member of nonmagnetic material having a substantially U-shaped section and connecting said first and second yokes to said third and fourth yokes.
Claim 2
Dependent Claim
135 words
A linear motor comprising: a first yoke and a second yoke spaced apart the width of a first gap from each other; a magnet spaced apart the width of a second gap from and arranged in opposed relation to said first yoke and second yoke; a coil fixed to the end of said magnet through a nonmagnetic material; a third yoke and a fourth yoke spaced apart the same width of a gap as that of said first gap from each other and so arranged in opposed relation to said magnet as to be spaced apart the same width of a gap as that of said second gap from said magnet; and a member of nonmagnetic material having a substantially U-shaped section and connecting said first and second yokes to said third and fourth yokes.
Claim 3
Dependent Claim
142 words
A linear motor, comprising: a first yoke; a second yoke spaced apart a predetermined width of a first narrow gap from said first yoke; a coil positioned to generate a magnetic flux through at least one of said first yoke and said second yoke; a magnet provided in opposed relation with and spaced apart a predetermined width of a second gap from said first and second yokes, said magnet being movable relative to said first and second yokes and said first gap; third yoke; a fourth yoke spaced from said third yoke by a gap of substantially a same width as said first narrow gap, said third and fourth yokes positioned opposed to said first and second yokes; and said magnet being positioned between said first and second yokes on one hand and said third and fourth yokes on the other hand.
Claim 4
Dependent Claim
142 words
A linear motor, comprising: a first yoke; a second yoke spaced apart a predetermined width of a first narrow gap from said first yoke; a coil positioned to generate a magnetic flux through at least one of said first yoke and said second yoke; a magnet provided in opposed relation with and spaced apart a predetermined width of a second gap from said first and second yokes, said magnet being movable relative to said first and second yokes and said first gap; third yoke; a fourth yoke spaced from said third yoke by a gap of substantially a same width as said first narrow gap, said third and fourth yokes positioned opposed to said first and second yokes; and said magnet being positioned between said first and second yokes on one hand and said third and fourth yokes on the other hand.
Claim 5
Dependent Claim
19 words
A linear motor as claimed in claim 2, wherein said coil is affixed to an end of said magnet.
References Cited (Backward Citations)
US3202886A
Cited
US3453510A
Cited
US3707924A
Cited
SU379025A1
Cited
DE2312668A1
Cited
US3999107A
Cited
US4233906A
Cited
US4335338A
Cited
US4439699A
Cited
US4603270A
Cited
US4697113A
Cited
US4803388A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-11-27 | 1993-05-29 | 1993-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-27 | 1997-05-29 | 1997-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-27 | 2001-05-29 | 2001-11-28 | $7700.00 | Window Closed / Lapsed |