US4400807A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stylus position detecting apparatus
Assignee: Hitachi Ltd
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Filing: 1981-11-13
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Granted: 1983-08-23
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Expires: 2001-11-13
Abstract
Abstract A stylus position detecting apparatus in use for a video disc player using a disc of the groove type, detecting plates for detecting leakage components of a high frequency signal supplied from a high frequency signal source and flowing through a flylead, and for reading out a recorded signal in a disc are provided on both sides of the flylead. The leakage signal components detected by the detecting plates are detected to positive and negative directions with respect to a reference voltage. These voltages obtained by the detections are added by an adder, to find a stylus position.
Inventors
- 👤 Tokinori Furuichi
- 👤 Junichi Ikoma
- 👤 Masao Oguri
- 👤 Yoshio Miura
- 👤 Keizo Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:15
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/24; G11; G11B; G11B21/00; G11B21/02; G11B21/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
150 words
A stylus position detecting apparatus for controlling an arm servo system of a disc player in which a high frequency signal is led from a high frequency signal source to a stylus electrode and a change of capacitance between said stylus electrode and a disc is taken out in the form of an information signal, said stylus position detecting apparatus comprising: detecting means positioned at the both sides of a conductor connecting the output of said high frequency signal source to said stylus electrode for detecting leakage components of the high frequency signal flowing through said conductor; means for supplying a reference potential; a detector circuit which detects a signal detected by said detecting means to positive and negative directions with respect to said reference potential; and adding means for adding two voltages obtained by the detections to said positive and negative directions to produce a stylus position detecting signal.
Claim 2
Dependent Claim
150 words
A stylus position detecting apparatus for controlling an arm servo system of a disc player in which a high frequency signal is led from a high frequency signal source to a stylus electrode and a change of capacitance between said stylus electrode and a disc is taken out in the form of an information signal, said stylus position detecting apparatus comprising: detecting means positioned at the both sides of a conductor connecting the output of said high frequency signal source to said stylus electrode for detecting leakage components of the high frequency signal flowing through said conductor; means for supplying a reference potential; a detector circuit which detects a signal detected by said detecting means to positive and negative directions with respect to said reference potential; and adding means for adding two voltages obtained by the detections to said positive and negative directions to produce a stylus position detecting signal.
Claim 3
Dependent Claim
16 words
A stylus position detecting apparatus according to claim 1, wherein said detecting means is electrode plates.
Claim 4
Dependent Claim
16 words
A stylus position detecting apparatus according to claim 1, wherein said detecting means is pick-up coils.
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) | 1986-08-22 | 1987-02-21 | 1987-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-22 | 1991-02-21 | 1991-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-22 | 1995-02-21 | 1995-08-23 | $7700.00 | Window Closed / Lapsed |