Patent US4675758A successfully refreshed from Google Patents.
US4675758A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic disc recording and/or reproducing apparatus
Assignee: Sony Corp
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Filing: 1984-01-30
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Granted: 1987-06-23
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Expires: 2004-01-30
Abstract
Abstract A magnetic disc recording and reproducing apparatus for magnetic discs wherein the gap of the recording and reproducing head is mounted parallel and ahead of a radial through the disc so as to record and reproduce a track and a pair of erasing heads are integrally formed with said recording and reproducing head and have gaps which are parallel and behind the same radial through disc so as to erase the outer edges of the track. The gap of the recording and reproducing head is symmetrically mounted with the erasing head gaps.
Inventors
- 👤 Yoshinori Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:36
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/012; G11B5/127; G11B5/265; G11B5/2652; G11B5/2654; G11B5/2655
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
229 words
A magnetic disc recording and/or reproducing apparatus for recording and reproducing signals on a rotating magnetic disc wherein the track pitch error is minimized and the tracking error margin is increased and satisfactory recording and reproducing performance may be obtained without requiring a high degree of precision in the drive mechanism comprising means for reading and writing information on a disc, said means comprising a recording/reproducing head for recording and reproducing a track mounted so as tomove over said rotating magnetic disc and to be transported in the radial direction of said disc and having a gap which is offset a fixed distance in a first direction and parallel to a radial line through said disc, and an erasing head connected to said recording/reproducing head mounted so as to move over said rotating magnetic disc and to be transported in the radial direction of said disc and having two gaps which are aligned on the opposite outer edges of said track and which are offset a fixed distance and in a second direction and parallel to said radial line through said disc, and wherein said two gaps of said erasing head are symmetrically arranged relative to the gap of said recording/reproducing head on opposite sides of said track and are equally spaced from said radial line through said disc whereby the track pitch error is reduced to a minimum.
Claim 2
Dependent Claim
229 words
A magnetic disc recording and/or reproducing apparatus for recording and reproducing signals on a rotating magnetic disc wherein the track pitch error is minimized and the tracking error margin is increased and satisfactory recording and reproducing performance may be obtained without requiring a high degree of precision in the drive mechanism comprising means for reading and writing information on a disc, said means comprising a recording/reproducing head for recording and reproducing a track mounted so as tomove over said rotating magnetic disc and to be transported in the radial direction of said disc and having a gap which is offset a fixed distance in a first direction and parallel to a radial line through said disc, and an erasing head connected to said recording/reproducing head mounted so as to move over said rotating magnetic disc and to be transported in the radial direction of said disc and having two gaps which are aligned on the opposite outer edges of said track and which are offset a fixed distance and in a second direction and parallel to said radial line through said disc, and wherein said two gaps of said erasing head are symmetrically arranged relative to the gap of said recording/reproducing head on opposite sides of said track and are equally spaced from said radial line through said disc whereby the track pitch error is reduced to a minimum.
Claim 3
Dependent Claim
215 words
A magnetic disc recording and/or reproducing apparatus for recording and reproducing signals on a rotating magnetic disc wherein the track pitch error is minimized and the tracking error margin is increased and satisfactory recording and reproducing performance may be obtained without requiring a high degree of precision in the drive mechanism, comprising means for reading and writing information on a disc and said means comprising a recording/reproducing head for recording and reproducing a track mounted so as to move over said rotating magnetic disc and to be transported in the radial direction of said disc and having a gap which is offset a fixed distance in a first direction and parallel to a radial line through said disc, and an erasing head connected to said recording/reproducing head mounted so as to move over said rotating magnetic disc and to be transported in the radial direction of said disc and having two gaps which are aligned on the opposite outer edges of said track and which are offset a fixed distance and in a second direction and parallel to said radial line through said disc so that the two gaps of said erasing head have a different azimuth angle from the gap of said recording/reproducing head whereby the track pitch error is reduced to a minimum.
Claim 4
Dependent Claim
215 words
A magnetic disc recording and/or reproducing apparatus for recording and reproducing signals on a rotating magnetic disc wherein the track pitch error is minimized and the tracking error margin is increased and satisfactory recording and reproducing performance may be obtained without requiring a high degree of precision in the drive mechanism, comprising means for reading and writing information on a disc and said means comprising a recording/reproducing head for recording and reproducing a track mounted so as to move over said rotating magnetic disc and to be transported in the radial direction of said disc and having a gap which is offset a fixed distance in a first direction and parallel to a radial line through said disc, and an erasing head connected to said recording/reproducing head mounted so as to move over said rotating magnetic disc and to be transported in the radial direction of said disc and having two gaps which are aligned on the opposite outer edges of said track and which are offset a fixed distance and in a second direction and parallel to said radial line through said disc so that the two gaps of said erasing head have a different azimuth angle from the gap of said recording/reproducing head whereby the track pitch error is reduced to a minimum.
Claim 5
Dependent Claim
46 words
A magnetic disc recording and/or reproducing apparatus for recording and reproducing signals on a rotating magnetic disc according to claim 2 wherein said two gaps of said erasing head are symmetrically arranged relative to the gap of said recording/reproducing head on opposite sides of said track.
References Cited (Backward Citations)
US4367505A
Cited
US4514772A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-22 | 1990-12-22 | 1991-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-22 | 1994-12-22 | 1995-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-22 | 1998-12-22 | 1999-06-23 | $7700.00 | Window Closed / Lapsed |