US4432021A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary recording medium reproducing apparatus
Assignee: Victor Company of Japan Ltd
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Filing: 1981-12-17
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Granted: 1984-02-14
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Expires: 2001-12-17
Abstract
Abstract A rotary recording medium reproducing apparatus reproduces a rotary recording medium having a spiral video signal track recorded with a video signal by use of a reproducing element, where the recording medium further has a reference signal track between each information signal track turn alternately switched over and recorded with first and second reference signals for an interval corresponding to each track turn, and recorded with a third reference signal at a position corresponding to the position where the first and second reference signals are switched over. The reproducing apparatus comprises a standard signal generating circuit for generating first and second standard signals respectively having frequencies equal to the horizontal scanning frequency and the vertical scanning frequency of the recorded video signal, a waveform shaping circuit for synchronizing a reproduced third reference signal with the first standard signal from the standard signal generating circuit, and subjecting the reproduced third reference signal to waveform-shaping, a switching signal forming circuit for forming a switching signal in response to the second standard signal from the standard signal generating circuit and the signal from the waveform shaping circuit, and a circuit for obtaining a tracking control signal for controlling tracking of the reproducing element by switching reproduced first and second reference signals by the formed switching signal.
Inventors
- 👤 Kenji Kaneko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:58
CPC Classifications
G; G11; G11B; G11B27/00; G11B27/10; G11B21/00; G11B21/02; G11B21/10; G11B21/106; G11B5/00; G11B5/48; G11B5/58; G11B5/584; G11B5/588; G11B5/592; G11B2220/00; G11B2220/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
213 words
A rotary recording medium reproducing apparatus for reproducing a rotary recording medium having a spiral video signal track recorded with a video signal by use of a reproducing element, said recording medium further having a reference signal track between each video signal track turn alternately switched over and recorded with first and second reference signals for an interval corresponding to said each track turn, and recorded with a third reference signal at a position corresponding to the position where said first and second reference signals are switched over, said reproducing apparatus comprising: a standard signal generating circuit for generating first and second standard signals respectively having frequencies equal to the horizontal scanning frequency and the vertical scanning frequency of said recorded video signal; a waveform shaping circuit for synchronizing a reproduced third reference signal with the first standard signal from said standard signal generating circuit, and subjecting the reproduced third reference signal to waveform-shaping; a switching signal forming circuit for forming a switching signal in response to the second standard signal from said standard signal generating circuit and the signal from said waveform shaping circuit; and means for obtaining a tracking control signal for controlling tracking of said reproducing element by switching reproduced first and second reference signals by said formed switching signal.
Claim 2
Dependent Claim
213 words
A rotary recording medium reproducing apparatus for reproducing a rotary recording medium having a spiral video signal track recorded with a video signal by use of a reproducing element, said recording medium further having a reference signal track between each video signal track turn alternately switched over and recorded with first and second reference signals for an interval corresponding to said each track turn, and recorded with a third reference signal at a position corresponding to the position where said first and second reference signals are switched over, said reproducing apparatus comprising: a standard signal generating circuit for generating first and second standard signals respectively having frequencies equal to the horizontal scanning frequency and the vertical scanning frequency of said recorded video signal; a waveform shaping circuit for synchronizing a reproduced third reference signal with the first standard signal from said standard signal generating circuit, and subjecting the reproduced third reference signal to waveform-shaping; a switching signal forming circuit for forming a switching signal in response to the second standard signal from said standard signal generating circuit and the signal from said waveform shaping circuit; and means for obtaining a tracking control signal for controlling tracking of said reproducing element by switching reproduced first and second reference signals by said formed switching signal.
Claim 3
Dependent Claim
59 words
A reproducing apparatus as claimed in claim 1 in which said standard signal generating circuit consists of an oscillating circuit for producing said first standard signal, and a frequency-dividing circuit for frequency-dividing the frequency of said first standard signal thus produced, and said frequency-dividing circuit is reset of the frequency-dividing operation by a signal from said waveform shaping circuit.
Claim 4
Dependent Claim
48 words
A reproducing apparatus as claimed in claim 1 in which said switching signal forming circuit consists of a counter for counting the second standard signal from said standard signal generating circuit, and a switching signal obtaining circuit obtaining said switching signal by an output signal of said counter.
Claim 5
Dependent Claim
59 words
A reproducing apparatus as claimed in claim 3 in which said video signal is recorded in units of N fields (N is an integer equal to or greater than two) for each track turn, said counter produces a signal having a period of N fields, and said switching signal obtaining circuit produces the switching signal for every N fields.
Claim 6
Dependent Claim
26 words
A reproducing apparatus as claimed in claim 3 in which said counter is reset of the counting operation by a signal from said waveform shaping circuit.
Claim 7
Dependent Claim
49 words
A reproducing apparatus as claimed in claim 3 in which said switching signal obtaining circuit consists of a detection circuit for detecting a fall in the output signal of said counter, and a monostable multivibrator triggered by an output signal of said detection circuit, for producing the switching signal.
Claim 8
Dependent Claim
46 words
A reproducing apparatus as claimed in claim 1 further comprising a motor for rotating said rotary recording medium, and a servo system for controlling the rotation of said motor, wherein said servo system is supplied with said first standard signal from said standard signal generating circuit.
References Cited (Backward Citations)
US4315283A
Cited
US4322836A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-13 | 1987-08-15 | 1988-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-13 | 1991-08-15 | 1992-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-13 | 1995-08-15 | 1996-02-14 | $7700.00 | Window Closed / Lapsed |