US3806786A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motor driving servo system for a tape recorder
Assignee: NEC Corp
•
Filing: 1973-01-30
•
Granted: 1974-04-23
•
Expires: 1993-01-30
Abstract
Abstract A servo system for a video tape recorder or the like is disclosed having a transducer head for recording and/or reproducing a control signal to control the phase of rotation of a capstan and/or head motor. The reproduced control signal is phase- or frequency-compared with a stable reference signal or a tachometer pulse to produce an error signal which controls the frequency of the power signal that drives the motor. Before the comparison, at least one of the two signals to be compared is phase- or frequency-modulated by the error signal.
Inventors
- 👤 M Inaba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:12
CPC Classifications
H; H02; H02P; H02P23/00; H02P23/18; H02P23/186
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
108 words
A servo system for a tape recorder or the like having a transducer head for reproducing a control signal to control the phase of rotation of a motor, said system comprising: means for comparing a predetermined characteristic of the reproduced control signal with a reference signal to produce an error signal having relatively low frequency components and relatively high frequency components; means for generating a driving signal for said motor, the frequency of said driving signal being determined in response tO said error signal; and means for modulating one of the reproduced control signal and said reference signal by the relatively high frequency components of said error signal.
Claim 2
Dependent Claim
108 words
A servo system for a tape recorder or the like having a transducer head for reproducing a control signal to control the phase of rotation of a motor, said system comprising: means for comparing a predetermined characteristic of the reproduced control signal with a reference signal to produce an error signal having relatively low frequency components and relatively high frequency components; means for generating a driving signal for said motor, the frequency of said driving signal being determined in response tO said error signal; and means for modulating one of the reproduced control signal and said reference signal by the relatively high frequency components of said error signal.
Claim 3
Dependent Claim
19 words
The servo system as claimed in claim 1, wherein said reproduced control signal is modulated at said modulating means.
Claim 4
Dependent Claim
32 words
The servo system as claimed in claim 1, wherein said tape recorder is a video tape recorder for a television signal having at least one rotary head for reproducing said television signal.
Claim 5
Dependent Claim
32 words
The servo system as claimed in claim 3, wherein said motor drives said rotary head and said reference signal is a tachometer pulse representing the phase of rotation of said rotary head.
Claim 6
Dependent Claim
18 words
The servo system as claimed in claim 3, wherein said motor drives a capstan for transporting the tape.
Claim 7
Dependent Claim
25 words
The servo system as claimed in claim 1, wherein said characteristic of said reproduced control signal is phase, said comparing means comprising phase comparing means.
Claim 8
Dependent Claim
16 words
The servo system as claimed in claim 6, wherein said modulating means comprises phase modulating means.
Claim 9
Dependent Claim
41 words
The servo system as claimed in claim 7, further comprising tuned amplifier means operatively interposed between said phase comparing means and said phase modulating means for applying said relatively high frequency components of said error signal to said phase modulating means.
Claim 10
Dependent Claim
27 words
The servo system of claim 8, in which said driving signal generating means comprises a voltage controlled oscillator connected to the output of said phase comparing means.
Claim 11
Dependent Claim
25 words
The servo system as claimed in claim 8, further comprising tachometer means for producing said reference signal representing the phase of rotation of said motor.
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) | 1977-04-22 | 1977-10-22 | 1978-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-22 | 1981-10-22 | 1982-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-22 | 1985-10-22 | 1986-04-23 | $7700.00 | Window Closed / Lapsed |