JP2800536B2 - Tracking control device for magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tracking control device for a magnetic recording / reproducing device.

[0002]

2. Description of the Related Art FIG. 2 shows the configuration of a tracking control device disclosed in Japanese Patent Publication No. 55-51256 and Japanese Patent Publication No. 55-51257. Reference numeral 1 denotes a magnetic tape, which is used for a video signal 2 and a reproduction tracking servo. The control signal 3 to be used is recorded. Reference numerals 4a and 4b denote rotating heads for reproducing the video signal 2. Rotating head 4a,
The drum 4b is mounted on a rotating drum 6 and is rotated at a predetermined speed by a drum motor 8 controlled by a drum motor driving circuit 7. Reference numeral 5 denotes a fixed control head, which reproduces the control signal 3.

A frequency generator 10 generates a frequency signal (FG signal) proportional to the number of revolutions.
Capstan motor drive control circuit 11 to which a signal is applied
The magnetic tape 1 is driven in the direction of an arrow 15 via a pulley 12, a belt 13, and a capstan 14 by a capstan motor (CP motor) 9 that is driven and controlled.

[0006] Reference numeral 16 denotes a control amplifier for amplifying the control signal 3, 17 denotes a phase comparison circuit using the output of the control amplifier 16 as one input, and 20 denotes a phase adjustment circuit, which is a magnet piece 1 attached to the rotating drum 6.
8 is adjusted by the fixed detection head 19, that is, the phase of the rotation angle signal of the rotation heads 4a and 4b is adjusted, and the resulting signal is used as the other input of the phase comparison circuit 17. The error signal of the phase comparison circuit 17 is applied to the capstan motor drive control circuit 11.

A rotary transformer 21 and a head amplifier 22 amplify the video FM signal reproduced by the rotary heads 4a and 4b via the rotary transformer 21 and add the amplified signal to an envelope detection circuit 23. 24 is a peak hold circuit, the output of the head amplifier 22 is applied to hold the maximum value V _p of the envelope signal. 25 is a comparator, an envelope detection signal V _e and the V _p is the output of the envelope detection circuit 23 is input.

Reference numeral 26 denotes a differentiating circuit, which is a comparator 25.
Is applied. Numeral 27 denotes a flip-flop circuit which inverts positive and negative output voltage polarities according to the output of the differentiating circuit 26. An integration circuit 28 integrates the output of the flip-flop circuit 27 and controls the phase of the phase adjustment circuit 20 according to the output polarity.

Next, the operation of the above configuration will be described. F G signal when is applied to the capstan motor drive control circuit 11 capstan motor 9, which is generated by the frequency generator 10 is controlled drive, pulley 12, the magnetic tape 1 through the belt 13 and the capstan 14 the arrow 15 Driven in the direction. Further, the drum motor 8 is rotated at a predetermined rotation speed by the drum motor drive circuit 7. At this time, the data is reproduced by the control head 5 and the control amplifier 1
The control signal amplified by 6 is supplied to the phase comparator 1
7 and the other input of the phase comparison circuit 17 receives a rotational phase signal from the fixed detection head 19.
The phase is adjusted by 0 and input.

The error signal from the phase comparison circuit 17 is applied to a capstan motor drive control circuit 11, and the output thereof finely controls the capstan motor 9 driven near a predetermined speed, thereby controlling the running of the magnetic tape 1. The control is performed so that the rotation phases of the rotary heads 4a and 4b and the reproduction phase of the control signal 3 have a phase relationship determined by the phase adjustment circuit 20. As a result, the rotary heads 4a and 4b scan a predetermined relative position of the track of the video signal 2 determined by the phase adjustment circuit 20.

On the other hand, the rotary head 4a, the video FM signal reproduced by 4b taken out by the rotary transformer 21 is amplified by the head amplifier 22 is input to the envelope detection circuit 23, wherein the detection envelope signal V _e is It is input to the comparator 25. The output of the head amplifier 22 is also applied to a peak hold circuit 24,
The output V _e of the output V _p and the envelope detection circuit 23 of the peak hold circuit 25 is applied to the comparator 25.
The comparator 25 compares V _p and V _e, the potential difference is determined whether or not appropriately set threshold e ₀ or greater than.

The output of the comparator 25 is applied to a differentiating circuit 26, which generates positive and negative pulses each time the output of the comparator 25 is inverted. Only by this negative pulse is the flip-flop circuit 27 triggered, inverting between positive and negative output voltage levels. The output of the flip-flop circuit 27 is added to the integration circuit 28 and integrated, and is changed into an increase / decrease signal corresponding to the output voltage polarity of the flip-flop circuit 27.
The phase of the phase adjustment circuit 20 is controlled.

[0011]

[0006] Conventional apparatus is constituted as described above, has the tentative automatic tracking adjustment function, followability and accuracy it was not enough. More detail
Then, in the conventional device described above, the rotating heads 4a and 4b
Tracking control is performed using only the output signal.
On the other hand, for example, a tape recorded on another VTR
Self-recorded tapes are usually tapes recorded on your own VTR
Track width and track linearity with some self-recording tapes
Are different. In addition, due to the mounting accuracy, the rotating head of another VTR
Is usually slightly different from its own VTR. I
Therefore, when the self-recorded tape is played, the rotating head 4
a, 4b can reliably trace the track
, Enough envelope for tracking control
Could not get a signal. Therefore, track
The accuracy of the tuning control was not sufficient. In addition, VH
As in the S HIFI system , the video signal is
In the method of recording the audio signal in the deep layer of the tape ,
It was necessary to find the optimum tracking values for the HIFI audio signal and the video signal.

That is, FIG. 7A shows a case where the magnetic tape 1 recorded by a VTR having a rotating video head 4 and a rotating HIFI audio head 40 is reproduced by the same VTR (self-recording / reproducing). In this case, FIG. As shown in b), the tracking value at which the envelope l _V of the video signal becomes the maximum and the tracking value at which the envelope l _A of the HIFI audio signal becomes the maximum are both t _0, and are applicable in principle.

[0013] However, when playing back a self-recorded tape,
The self-recording tape and track width and track width, as described above.
And track linearity and head mounting position are different
Therefore, the tracking value of the maximum envelope value of the video signal may be different from the tracking value of the maximum envelope value of the HIFI audio signal. More details
In the video track width, generally, VHS system 5 8 [mu] m in the standard mode (SP mode), is defined as the long-time mode (EP mode) 19 .mu.m. But actually
Is the other VTR, or not record the information in 58μm or less in the track width even SP mode, the E P mode
The head width of the EP head used is 19 μm or more
Or may be. Also, due to the mounting accuracy, other V
Arrangement step of the rotating video head 4 and rotating HIFI audio head 40 of the TR is usually different from the self VTR
Often . Therefore, the track of the self-recorded tape is surely
Cannot be traced to
Not get the required amount of envelope signal
Was. Therefore, even in the HIFI system, the tracking system
Your accuracy was inadequate.

[0014] The invention has been Do to solve the above problems, track like other himself recording tape
Tape width and track linearity are different from self-recording tapes.
Obtain high-precision tracking values even when
This enables tracking control to be performed with high accuracy.
It is an object of the present invention to obtain a tracking control device of a magnetic recording / reproducing device which can perform the following.

[0015]

Means for Solving the Problems] tracking control apparatus of the magnetic recording and reproducing apparatus according to the present invention, the rotation Bideohe' de
The 及 beauty FE head precedes the rotary video heads
A plurality of envelope detection means for respectively detecting signals from a plurality of heads, including a plurality of heads, a means for synthesizing each envelope signal, a means for calculating an optimum tracking amount based on the synthesized envelope signal, and a magnetic field based on the optimum tracking amount. it is provided with a control means for tracking control of the capstan motor for running a tape.

[0016]

According to the present invention, the rotating video head and the F
E corresponding to signals from a plurality of heads including the E head
The Beropu signal based on the synthesized synthesis envelope signal tracking control Ru performed. The FE head rotates
It has a head width wider than the head width of the video head.
Therefore, signals from multiple tracks can be obtained.
The track width and track linearity
Different self-recorded tapes are required for tracking control.
A required amount of envelope signal can be obtained. Only
However, due to the wide head width, the accuracy of track linearity
It is difficult to reliably detect the envelope signal
Head with small head width (especially for long-time mode
Unlike EP heads that can be
Indeed, it can be detected. Therefore, each head
Optimum tracking value is obtained by combining signals
Can be

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration according to this embodiment.
The portions indicated by 1, 14, 16 and 21 to 23 are the same as the conventional ones. 10a is a drum frequency generator, 106a and 106
b is a head wider than the head width of the rotary heads 4a and 4b.
FLE / video sharing (erasing / playback sharing) head, which is a FE (flying erase) head having a width, is a reference for generating a reference signal for operating servo control circuits of both the rotating drum 6 and the capstan 14. It is a signal oscillator. In case of NTSC system, 3.58MHz oscillation circuit 3
0a, down counters 30c and 30d for counting down the oscillation signal, and a down counter / phase correction circuit 30b.

Reference numerals 40a and 40b denote rotary HIFI audio heads, and 31 denotes a rotary head 4a, 4 which correctly rotates the rotary drum 6 at 1800 rpm and is mounted opposite to each other.
A drum servo control circuit that also controls the rotation phases of b, 40a, and 40b, and mixes and smoothes the outputs of the drum phase comparison circuit 31a, the drum frequency comparison circuit 31b, the drum flip-flop signal generation circuit 31c, and the comparison circuits 31a and 31b. And a mixing filter 31d.

Numeral 32 denotes a capstan servo control circuit for rotating the capstan 14 at a predetermined speed and running the magnetic tape 1 at a predetermined speed and tracking position.
It comprises a capstan phase comparison circuit 32a, a capstan frequency comparison circuit 32b, and a mixing filter circuit 32c for mixing and smoothing the outputs of both comparison circuits 32a and 32b.

Reference numeral 33 denotes a delay circuit for delaying the reference signal of the drum phase comparison circuit 31a, and reference numeral 34 denotes a 1/2 frequency vertical signal generating circuit for generating a 1/2 frequency vertical reference signal based on the delayed signal. This signal is used as a reference for a tracking control signal created by the microcomputer 49. Reference numeral 35 denotes a delay circuit that delays the drum flip-flop signal to create a HIFI head switch signal.

Reference numeral 102 denotes a delay circuit for delaying a drum flip-flop signal to generate a FLE / video shared head switch signal, and 100 denotes a FLE / video shared head 10
A video signal head amplifier for amplifying the video signals spread in 6a and 106b, a HIFI audio head amplifier for amplifying a HIFI audio signal, and a H for detecting the amplitude of the HIFI audio signal converted into an FM signal.
IFI audio envelope detection circuit, 101 is FL
E / Video signal envelope detection circuit for envelope detection of a signal obtained by the video common head, 103 is a digital signal for converting the envelope detected video signal into a digital signal.
A / D conversion circuit, 46 is an A / D conversion circuit for digitally converting a HIFI audio envelope detection signal, 104 is an inversion circuit for inverting the signal digitally converted by the A / D conversion circuit 103 during EP reproduction, and 105 is an A / D conversion circuit. Conversion circuit 1
A memory for storing the output of 03 or the output of the inverting circuit 104, a memory for storing the output of the A / D conversion circuit 46, a 49 for adding the outputs of the memories 48 and 105 to obtain a synthesized envelope value, and A microcomputer that compares the envelope value with the discrimination value and creates a control pulse;
9b and a tracking control signal generation circuit 49c. 107 is an A / D conversion circuit, and 108 is a memory.

Next, the operation of this embodiment will be described. First, an FC signal (for example, 720) from a drum frequency generator (drum FC) 10a attached to the drum motor 8
Hz) and the output signal of the down counter 30c which counts down the 3.58 MHz reference oscillation signal is compared by the drum frequency comparison circuit 31b. The rotational phase of the rotary heads 4a and 4b is detected by the magnet piece 18 and the drum phase detection head 19 attached to the rotary drum 6, and the drum PG pulse signal (30 Hz) is input to the drum flip-flop circuit 31c. The drum phase comparison circuit 31a compares the output signal with the output signal of the down counter phase correction circuit 30b, which counts down the 3.58 MHz reference oscillation signal and corrects the phase. The output signals of the comparison circuits 31a and 31b are smoothed and mixed by the mixing filter 31d and applied to the drum motor drive circuit 7, whereby the speed and phase of the drum motor 8 are controlled to be stable at 1800 rpm.
Is performed.

On the other hand, a capstan frequency comparison circuit compares the FC signal (for example, 720 Hz) of the capstan frequency generator 10 attached to the capstan motor 9 and the output signal obtained by counting down the 3.58 MHz reference oscillation signal by the down counter 30d. Compare at 32b. The control signal detected by the control head 5 and amplified by the control amplifier 16 and the microcomputer 4
The tracking control signal created in step 9 is compared with the capstan phase comparing circuit 32a. The two comparison circuits 32
The output signals a and 32b are smoothed and mixed by the mixing filter 32c and applied to the capstan motor driving circuit 11, and the speed and phase of the capstan motor 9 are controlled to be driven at a stable speed.

The output signal of the drum flip-flop circuit 31c is applied to the video signal head amplifier 22 as a rotary video head switch signal, and the input from the video heads 4a and 4b is switched.

As shown in FIG. 4, in the rotating drum 6,
The HIFI audio heads 40a and 40b are mounted at an angle of 120 ° with respect to the video heads 4a and 4b, and the output of the drum flip-flop circuit 31c is output by the delay circuit 35 to the HIFI audio heads 40a and 40b.
Is applied to the HIFI audio head amplifier 42, and the HIFI audio head 40
Inputs from a and 40b are switched. Thus, the video signal amplified by the head amplifiers 22 and 42 and the HI
The FI audio signal is switched according to the phase of each head, and continuous envelope signals are extracted by the envelope detection circuits 23 and 44.

Here, the video heads 4a and 4b and the HI
Using the FLE / video shared heads 106a and 106b preceding the FI audio heads 40a and 40b,
By calculating and adding signals newly detected by the FLE / video shared heads 106a and 106b to the current automatic tracking control signal, highly accurate control can be performed.

When the step arrangement of each head on the rotary drum 6 is as shown in FIG. 3, the video heads 4a and 4b which are actually reproduced at the time of SP reproduction shown in FIG.
The LE / video shared heads 106a and 106b are located at the position of one field + 120 °, and in the case of EP reproduction shown in FIG.
6b is located at 4 fields + 120 °. here,
An azimuth is inserted as shown in FIG. 4 so that the envelope can take out the azimuth of the FLE / video shared heads 106a and 106b, and the FLE / video shared heads 106a and 106b
6b. The flip-flop signal from the drum flip-flop circuit 31c is delayed by the delay circuit 102 so that a continuous envelope can be extracted from the FLE / video shared heads 106a and 106b. To get the envelope.

The above envelope is converted to an A / D conversion circuit 103
In the case of EP, since the curve of the envelope amount is inverted as shown in FIG. 6B, the digital value is inverted by an inversion circuit 1 to further invert the curve.
Enter in 04. The video signal envelope of the FLE / video heads 106a and 106b output from the circuit 104 or 105 is input to the memory 105, delayed so as to be synchronized with other signals, and input as a signal C to the adder 49a of the microcomputer 49. You.

On the other hand, the envelope signals output from the envelope detection circuits 23 and 44 are A / D-converted by A / D conversion circuits 107 and 46, respectively.
After being stored by the adder 49, the adder 49
is input to a. Therefore, the adder 49a outputs the signals A,
B and C are added, and as shown in FIGS. 8 and 9, the maximum value of the combined envelope becomes clearer than when the signals A and B are added, and it becomes easier to set the optimum value of the tracking value. or,
At this time, in the case of the standard mode, the synthesized envelope signal A
The self-recording (48 μm), 48 μm or more and 48 μm or less (other self-recording) can be distinguished by the form of + B + C, and the microcomputer 49 processes the optimum point in the synthetic envelope (in the case of other self-recording, the maximum point is the best image quality, May not be the best sound quality.) FIG.
9 shows the case where the video track is written at 58 μm, and FIG. 10 shows the case where the video track is written at 45 μm (other self-recording).

Further, the microcomputer 49 calculates an optimum tracking value based on the information obtained from the synthesized envelope signal, and the calculated tracking value is applied to the capstan phase comparison circuit 32a to perform tracking control.

In the above embodiment, the VHS system HIFIVTR (deep recording system) has been described.
Regarding the reproduction of the HS system non-HIFI, since the HIFI envelope is not detected, it is only necessary to provide a program that operates only with the video signal and the signal extracted by the FLE / video shared heads 106a and 106b and performs the operation by switching with the microcomputer 49. It is feasible. In the above embodiment, the VHS format is used, but the present invention is not limited to this system. Also, a V provided with two heads having different azimuth angles and a FLE head on the rotating drum 6
Although the TR has been described, the present invention can also be applied to a VTR provided with multiple heads and FLE heads such as the CVHS system.

[0032]

As described above, according to the present invention, the FE
Since the signal from the pad is used for tracking control,
Ideal for self-recorded tapes as well as other self-recorded tapes
Tracking value can be obtained. Therefore,
Racking control can be performed with high accuracy. That
High in both self-recorded and self-recorded
High quality reproduced images and reproduced sounds can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a device of the present invention.

FIG. 2 is a configuration diagram of a conventional device.

FIG. 3 is a diagram showing a step arrangement of each head on a rotating drum.

FIG. 4 is a layout view of each head on a rotating drum.

FIG. 5 is a diagram showing trace positions of a video head and a FLE / video shared head.

FIG. 6 is a diagram illustrating a relationship between a tracking value and an envelope amount in the FLE / video shared head.

FIG. 7 is a diagram showing an envelope of a reproduction signal from a video head and a HIFI audio head when self-recording is performed.

FIG. 8 is a diagram showing a synthetic envelope in the case of self-recording of the apparatus of the present invention.

FIG. 9 is a diagram showing a composite envelope when recording is performed with a track width of 58 μm in the device of the present invention.

FIG. 10 is a diagram showing a composite envelope in the case of another self-recording of the apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic tape 4a, 4b Rotating video head 5 Control head 6 Rotating drum 7 Drum motor drive circuit 8 Drum motor 9 Capstan motor 11 Capstan motor drive control circuit 14 Capstan 23,44,101 Envelope detection circuit 30 Reference signal oscillator 31 Drum servo control circuit 32 Capstan servo control circuit 40a, 40b Rotating HIFI audio head 49 Microcomputer 106a, 106b FLE / video shared head

Claims (1)

(57) [Claims] 1. A each envelope detection means for each envelope detection signals from the plurality of heads including the rotation Bideohe' de及 beauty FE head precedes the rotating video heads, and means for combining the envelope signal, combining the envelope means for calculating the optimum tracking amount based on the signal, the tracking control of the magnetic recording and reproducing apparatus characterized by comprising a control means for tracking control of the capstan motor for running the magnetic tape on the basis of the optimum tracking weight apparatus.