Patent US5084849A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5084849A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for setting the loop gain of servo loops in a disc player

Assignee: Pioneer Corp
•
Filing: 1989-11-08
•
Granted: 1992-01-28
•
Expires: 2009-11-08
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A loop gain setting method automatically sets the loop gain of a focus servo loop and a tracking servo loop of a disc player for playing a disc. Firstly the loop gains of the focus servo loop and the tracking servo loop are set, and subsequently the appropriateness of the set values of loop gains is judged by comparing the set values of the loop gains with each other. According to another aspect of the present invention the loop gains of the focus servo loop and the tracking servo loop are set, and subsequently the appropriateness of the set values of loop gains is judged by comparing at least one of the set values of the loop gains with a sensed value of the amplitude of the envelope of an RF signal read-out from the disc.

Inventors

  • 👤 Hidehiro Ishii
  • 👤 Noriyoshi Takeya
  • 👤 Chiharu Miura
  • 👤 Tatsuya Fukuda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 15:15
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/0941

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 85 words
A loop gain setting method for automatically setting the loop gain of a focus servo loop and a tracking servo loop of a disc player while playing a disc, the method comprising: (a) setting a value of loop gain of the focus servo loop; (b) setting a value of loop gain of the tracking servo loop; and (c) determining the appropriateness of the loop gain values by comparing said set loop gain values to determine if they are within a predetermined range of each other.
Claim 2
Dependent Claim 85 words
A loop gain setting method for automatically setting the loop gain of a focus servo loop and a tracking servo loop of a disc player while playing a disc, the method comprising: (a) setting a value of loop gain of the focus servo loop; (b) setting a value of loop gain of the tracking servo loop; and (c) determining the appropriateness of the loop gain values by comparing said set loop gain values to determine if they are within a predetermined range of each other.
Claim 3
Dependent Claim 46 words
The loop gain setting method of claim 1, further comprising the step of: resetting at least one of said set values of loop gains if a result of the determination in step (c) indicates that the loop gains are outside said predetermined range of each other.
Claim 4
Dependent Claim 51 words
The loop gain setting method of claim 1, further comprising the step of: replacing at least one of said set values of loop gain by an initial setting value, if a result of the determination in step (c) indicates that said loop gains are outside said predetermined range of each other.
Claim 5
Dependent Claim 122 words
A loop gain setting method for automatically setting the loop gain of a focus servo loop and a tracking servo loop of a disc player while playing a disc, the method comprising: (a) setting a loop gain value of the focus servo loop; (b) for setting a loop gain value of the tracking servo loop; (c) sensing an amplitude of an envelope of an RF signal read out from said disc; and (d) determining the appropriateness of said value settings of the loop gains by comparing at least one of said set values of loop gain with a sensed value of the amplitude obtained in step (c) to determine if said loop gain is within a predetermined range of said sensed amplitude.
Claim 6
Dependent Claim 122 words
A loop gain setting method for automatically setting the loop gain of a focus servo loop and a tracking servo loop of a disc player while playing a disc, the method comprising: (a) setting a loop gain value of the focus servo loop; (b) for setting a loop gain value of the tracking servo loop; (c) sensing an amplitude of an envelope of an RF signal read out from said disc; and (d) determining the appropriateness of said value settings of the loop gains by comparing at least one of said set values of loop gain with a sensed value of the amplitude obtained in step (c) to determine if said loop gain is within a predetermined range of said sensed amplitude.
Claim 7
Dependent Claim 47 words
The loop gain setting method of claim 4, further comprising the step of: setting again at least one of said values of loop gain if a result of the determination in step (d) indicates that said loop gain is outside said predetermined range of said sensed amplitude.
Claim 8
Dependent Claim 52 words
The loop gain setting method of claim 4, further comprising the steps of: replacing at least one of said set values of loop gain by an initial setting value, if a result of the determination in step (d) indicates that said loop gain is outside said predetermined range of said sensed amplitude.

References Cited (Backward Citations)

US4787076A Cited
US4707648A Cited
US5003521A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-01-27 1995-07-29 1996-01-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-01-27 1999-07-29 2000-01-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-01-27 2003-07-29 2004-01-28 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag