US4574369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tracking/focusing device for positioning an optical lens unit
Assignee: Ricoh Co Ltd
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Filing: 1983-01-28
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Granted: 1986-03-04
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Expires: 2003-01-28
Abstract
Abstract An optical disc player/recorder includes a composite coil device for controlling both tracking and focusing functions of a moveable objective lens unit. A bobbin having orthogonal coils is supported by spring members and holds the objective lens. A magnetic gap field intersects both coils and current through each controls the focusing position and tracking position of the lens.
Inventors
- 👤 Hiroshi Koide
- 👤 Junichi Watanabe
- 👤 Shigemoto Tenmyo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:31
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/0925; G11B7/0932; G11B7/093; G11B7/0935
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
202 words
An optical positioning device for positioning an optical lens unit relative to information recording tracks on an optical recording surface comprising: a body case having a vertical passageway with a central vertical axis; a bobbin moveably disposed in said vertical passageway and supporting said optical lens unit, and having a vertical hollow defined therein; top and bottom support members resiliently connecting respective top and bottom portions of the bobbin to wall portion of the vertical pasageway so that said bobbin can move in both a vertical direction and a horizontal direction; a first coil wound around a vertical axis of said bobbin; a second coil would around a horizontal axis of said bobbin and circumscribing the bobbin in a vertical plane near the central vertical axis of the vertical passageway; magnetic field generating means including an inner portion located in the hollow of said bobbin and an outer portion located outside said bobbin, said inner and outer portions defining a magnetic flux gap whose magnetic flux intersects both first and second coils so that the bobbin moves in said vertical direction when current is passed through the first coil and in said horizontal direction when current is passed through the second coil.
Claim 2
Dependent Claim
202 words
An optical positioning device for positioning an optical lens unit relative to information recording tracks on an optical recording surface comprising: a body case having a vertical passageway with a central vertical axis; a bobbin moveably disposed in said vertical passageway and supporting said optical lens unit, and having a vertical hollow defined therein; top and bottom support members resiliently connecting respective top and bottom portions of the bobbin to wall portion of the vertical pasageway so that said bobbin can move in both a vertical direction and a horizontal direction; a first coil wound around a vertical axis of said bobbin; a second coil would around a horizontal axis of said bobbin and circumscribing the bobbin in a vertical plane near the central vertical axis of the vertical passageway; magnetic field generating means including an inner portion located in the hollow of said bobbin and an outer portion located outside said bobbin, said inner and outer portions defining a magnetic flux gap whose magnetic flux intersects both first and second coils so that the bobbin moves in said vertical direction when current is passed through the first coil and in said horizontal direction when current is passed through the second coil.
Claim 3
Dependent Claim
27 words
A positioning device according to claim 1 wherein said vertical passageway, said bobbin and said magnetic generating means have circular cross sections in a common horizontal plane.
Claim 4
Dependent Claim
19 words
A positining device according to claim 1 wherein said magnetic field includes a permanent magnet having a ring shape.
Claim 5
Dependent Claim
16 words
A device according to claim 3 wherein said inner and outer portions are ring shaped yokes.
Claim 6
Dependent Claim
18 words
A device according to claim 1 wherein said first and second coils are substantially perpendicular to each other.
Claim 7
Dependent Claim
36 words
A device according to claim 1 further comprising a control circuit for supplying control currents to said first and second coils so that the optical lens unit is properly positioned relative to said information recording tracks.
References Cited (Backward Citations)
US4021101A
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US4193091A
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JPS5523835A
Cited
JPS5664144A
Cited
US4408313A
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US4482988A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-03 | 1989-09-02 | 1990-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-03 | 1993-09-02 | 1994-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-03 | 1997-09-02 | 1998-03-04 | $7700.00 | Window Closed / Lapsed |