JPS6089854A - Information signal reproducing device - Google Patents

Abstract

PURPOSE:To attain excellent reproduction automatically by utilizing effectively a superimposed pilot signal on a recording track and an oscillating means having plural oscillating frequencies. CONSTITUTION:The oscillating means 17 oscillates alternatively plural kinds of frequency signals in response to a designating means of the reproduction form corresponding to the interval between tracks. Furthermore, the means 18 obtains a signal to control converting means 3A, 3B by using a frequency signal of the means 17 to move at least one of rotary heads 2A-2D in a direction orthogonal to the rotary face. Then the time information to the repetitive period of the pilot signal reproduced by the rotary heads is obtained and the means 15 controls the means 16 based on the time information and the frequency signal of the means 17. Thus, excellent reproduction is attained automatically.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to an information signal reproducing device, and more particularly, to an information signal reproducing device that determines the interval between recording tracks sequentially formed on a recording medium in a direction intersecting the transport direction thereof, and automatically determines the reproduction mode. The present invention relates to an information signal reproducing device that can change the information signal.

<Description of the Prior Art> A device of this type is a magnetic recording/reproducing device tt (hereinafter referred to as V
During recording, the interval between each recording track (hereinafter referred to as TP) is determined by selecting the tape transport speed, and during playback, the interval between recording tracks is determined, and the tape There is a known type that can achieve good reproduction by automatically selecting the transfer speed and the head to be used. Hereinafter, in this specification, V of this infarction
This will be explained using an example of TRy.

Conventionally, in this type of V'[(J-track formed at the end of the tape during recording; During playback, this control signal t, -, 1r4 is generated and by knowing its frequency, the tape transport speed at tl[;0,
In other words, the system determines the 'vP' and automatically selects a suitable playback operation mode by controlling the head and tape transport speeds 1111 used during playback.

In recent years, with the trend towards miniaturization and high-density recording of V T It, a type of V '1' IT has been proposed that does not record the above-mentioned control signal but records a pilot signal for tracking on the video signal. ing. This kind of VTR
In general, a tracking control signal is obtained by sequentially superimposing a plurality of types of pilot signals on each track and detecting the level difference of the pilot 'IN signals from both adjacent tracks of the reproduced track.

In addition, in recent years, in VTRK, a rotating head is mounted on an electro-mechanical conversion element such as a bimorph element, and by displacing the head in a direction perpendicular to the direction of rotation, variable speed playback such as slow motion playback and high-speed search playback is possible. In some cases, a head that can faithfully trace a recording track has also been proposed.

This type of VTI (K) does not generate noise bars like conventional ones even during variable speed playback, and can provide a very high quality playback image. By the way, in this type of VTR, the above The head displacement means such as an electro-mechanical transducer must be controlled using a control signal tone corresponding to its playback speed and TP.

By the way, high-density recording can be achieved in the VTR used for pilot signal sound tracking control as described above, but since there is no control signal as described above, the T.
Py, - no directly representative signal.

Therefore, automatic determination of TP is not performed, and generally there is only one type of tape speed during recording, that is, TP.

On the other hand, the above-mentioned VT capable of performing noiseless variable speed playback 2
In RK, control signals differ depending on T IJ K, so if there are several #1 TPs during recording, the control signals will vary accordingly. Generally, the slope of this control signal is proportional to the number of tracks that the head crosses in one field period, and in order to obtain this slope, it depends on the tape transport speed.From the white signal, 1) Yield period ni l'
What is necessary is to subtract a so-called still pattern signal having a slope that shifts the shifting means by J'P. This methyl pattern signal differs depending on the TP, so Ill IJ?
υIn order to stop the control signal of the transition means in several types of VTRs, a still pattern (g) is created by counting the output of an oscillator with multiple oscillation frequencies according to the recording TP. I had to do it.

<Object of the Invention> The present invention has been made in view of the above-mentioned problems, and effectively utilizes an oscillation means having a plurality of oscillation frequencies and a pilot signal that is repeatedly superimposed on the recorder's rack. 11) To provide an information signal reproduction value flit that can automatically perform good reproduction regardless of the medium transport speed and the interval between recording tracks during raw recording.
:1 target.

<Description of Example 5 The present invention will be explained below using examples.

FIG. 1 is a diagram showing a schematic configuration of a reproduction system of a VTR as an embodiment of the present invention. In the figure, 1 is magnetic tape, 2
A, 2B, 2(, ', and 2D are magnetic heads, respectively. The two heads and head 2B have the same head width but different azimuth angles, and heads 2C and 2D have the same head width but different azimuth angles. The head widths of heads 2A and 2B are wider than the head width of heads 2C12D;
B is a mode head for recording and reproducing in a wide TPO pattern (hereinafter referred to as long time mode) by increasing the tape transport speed, and RAD 2C and 2D are heads for recording and reproducing in a wide TPO pattern by increasing the tape transport speed.
This is a head for recording with a narrow recording pattern (hereinafter referred to as long-time mode). However, here, Herad 2A, 2
The head width of B is head 2C.

It is assumed that the TP of the short time mode is twice that of 2D, and the TP of the short time mode is twice that of the long time mode.

3A and 3B are head shifting means such as bimorphs having heads 2A and 2B attached to one end, respectively. Therefore head 2
A, 21J is also used as a variable-speed internal head,
In both the long-time mode and the short-time mode, it is assumed that the bimorph 3 A is displaced by a control signal to be described later, and -(11) life is performed. Therefore, there are two heads, head 2C, head 2B and Herad 2D.
The azimuth angles are set to be equal to each other.

4 is a head motor for rotating the heads 2A, 213, 2C, and 2D; 5 is a head motor rotation detector that outputs pulses related to the 240 rotations of the heads 2A, 213, 2C, and 2D; 6&'
A head motor control circuit that rotates the head motor 4 at a predetermined phase for a constant period of 1 minute based on the pulses 11 and F at the rotation detector 5; The head is a switch for making the playback signal a continuous signal, and switch 7 is a rotating,
It is switched by the head motor control circuit 6 in relation to the pulses at the detector 5: 30 Hz arrow R rectangular wave signals (hereinafter referred to as 39P and G).

Reference numeral 8 designates a capstan for feeding the tape 1 four times, which works together with a pinch rope (not shown) to detect the 10 rotations of the flywheel, and 11 to detect the 100 revolutions of the flywheel and generate pulses (
FG)'v output flywheel rotation detector, 12 is a capstan control that drives the capstan 8 so that the heads 2A, 2B, 2C, 2I) can faithfully toss the recording track. circuit, 13 is a low pass filter (LPF) that separates the pilot signal superimposed on the reproduced RF signal obtained by the head switch 7, 14 is LPF'
A tracking control circuit (AT
F circuit), 15 is an error determination circuit that determines the interval between recording tracks and determines whether the operation mode specified by the mode selector 16 corresponds to the recording T P; 17;
18 is an oscillation circuit that selectively supplies a plurality of frequency signals to the error discrimination circuit 15 according to the mode selector 16; and 18 is a control signal that controls the bimorphs 3A and 3B4 according to the outputs of fi' 19 is a reproduction signal processing circuit which obtains a video signal in the original signal form from the reproduction RF signal, and 20 is an output terminal from which the reproduction video signal is output.

FIG. 2 is a diagram showing the main tracks on a magnetic tape when a plurality of types of pilot signals for tracking are multiplexed and recorded on a video signal in a short time mode.

AI, A2, As are tracks formed by two heads with the same azimuth angle, respectively, Bl,
B2. Bs are tracks formed by heads having the same azimuth angle as the head 213, respectively. fl, fz, f4. on each track. , I'3 indicate the frequency of the pilot signal which is added to the video signal of each track, respectively, and 16 is an arrow indicating the direction in which each track is traced.

During playback, there are two heads 2A with different azimuth angles.

2B sequentially tracks 8l, ) rack 13t, )
Rack A2. Track B2. Track A3...
・And (is a breeding cow, and along with this, fx, fz, f<,
A pilot signal having a frequency 2 of l'a, (s, fl----) (hereinafter referred to as F I'1. (l.

fl, fa, fa - ") are sequentially i
1) The frequency of these pilot signals is much lower than the frequency band of the video signal and is not affected by the azimuth angle (there is no azimuth loss). Track width is T
If it is slightly larger than P, not only the pilot signal of the reproduced track but also the pilot signals of both adjacent tracks are reproduced. The ATF circuit 13 in FIG. 1 can obtain an accurate tracking error signal including the direction and magnitude of track deviation by detecting the reproduction levels of pilot signals obtained from both adjacent tracks. ATJi obtained in this way
The signal is supplied to the capstan control circuit 11, which controls the movement of the chive 10 by the capstan 7, and functions to perform good tracking under normal pressure.

In addition, in the long time mode, the mode selector 15 changes the rotation phase of the head motor 30, and the switch 6 changes the head motor 30 rotation phase.
The operation is the same except that the signal reproduced from C and 2D is a continuous wave, and the recording pattern is also the same except for the difference in TP and track inclination, so a description thereof will be omitted.

Further, during variable speed reproduction, each track is traced by the heads 2A and 2B both in the short time mode and in the long time mode. In this case, since the order of generation of the pilot signals obtained upstream of the reproduced RLi'Li changes, the ATFu path 14
is configured to deal with this.

The control signals supplied to the bimorphs 3A and 3B during variable speed playback will now be explained. As mentioned above, this control signal is a signal whose slope is 7 different from that of the signal whose slope corresponds to the speed of the tape. It is obtained by subtracting K. A signal having a slope corresponding to the tape speed 1y is obtained by counting FGi.

On the other hand, a signal having a slope ' corresponding to TP is obtained by obtaining a signal having an excavation frequency corresponding to TP by the oscillation circuit 17 and counting the missing signal.

FIG. 3 shows an example of the oscillation circuit 17 in FIG. 1, in which the output of the oscillator 21 is output as is in the short-time mode,
In the long-time mode, the frequency is divided by the 1/2 frequency divider 22 and output. That is, when variable speed playback in the short time mode is specified by the mode selector 16, the switch 23 is connected to the S side, and when variable speed playback in the long time + MI mode is specified, the switch 23 is connected to the L side. It is connected to the.

The control signal generating circuit 18 obtains a control signal by subtracting the signal v obtained by counting the output of the oscillation circuit 17 and the signal obtained by counting FGv, and shifting the signal by nTP every 30 PG. The details of this can be found in, for example, Japanese Patent Application No. 1,5368 filed earlier by the applicant.
This is what is stated in No. 6.

Next, the operation of the error determination circuit 15 shown in FIG. 1 will be explained. 412 is a diagram showing a specific example Z of the error discrimination circuit 15 in FIG. 1, and FIG. The figure shown in FIG. 6 is a timing chart for explaining the operation of the circuit shown in FIG. The head width of heads 2A and 2B is twice that of yuru'rP, and the head width of heads 2C and 2JJ is +°1υ
) 2 Assuming that it is an A sound.

In the 51st name <At-(1)l, the actual firing i!i, indicates the boundary +ff- of each recording trunk, and the broken line indicates the IJf raw at the endogenous time. It shows the trace trajectory.

First, when I tried to play back a tape recorded in short-time 1μm mode (1) in long-time mode,
Let's think about it. Recorded track and endogenous trace in this case! The l1lL trace is shown in Figure 5 (5). ff1
p, 4 +'Z+ - 30 is L in Figure 1
From Pii' l 4 σ) circle 4Lノ (Ironto signal is supplied) 嬬"r-. This σ) Ill/:
L: ノ (Ilot signal is pantone
F)3. i(II' supply le, fl, (z, f3
．． r4d) Ut, only the pilot signal component of the arbitrary tv-xa nq is extracted. For example, it is used as a means to extract fl, and continues to be used.

"f" extracted by BpF'3L+ is the detection time 1 35
envelope detection is performed. This]・η wave times 11! 3 each
For example, the output waveform of 5 is shown in Figure 6 (21) -11-01
1 (becomes. 36 is a comparator, 4ψ wave circuit: 1
5σ) Compare the output with the reference voltage vO. The output of this converter is shown in FIG. 6(b).

On the other hand, the terminal 31 is a terminal to which a signal obtained by the oscillation circuit 17 shown in FIG. 1 is input. This signal is counted by a counter 39, and the counter 39 is reset by the output of the above-mentioned comparator 36 delayed by a differential time in a delay circuit 38.

40 is a D/A converter that performs digital-to-analog conversion (D/A conversion) of the output of the counter 39.
The output of the A converter 40 is as shown in the sixth @<c).

Similarly, when trying to reproduce a magnetic tape recorded in a long-time mode in a short-time mode, the recording track and reproduction trace locus on the magnetic tape are shown in FIG. 5, and the output of the detection circuit 35 at this time, Output of comparator 36 and D/
The output of the A converter 40 is shown in FIG. 6(d), (e),
Shown in (f).

In addition, when a magnetic tape recorded in short time mode is played back in short time mode, and when a magnetic tape recorded in long time mode is played back in long time mode, the appearance on the magnetic tape is shown in Figure 5 (C). ). v61'Xl (g),
(h) and (i) respectively show the outputs of the detection circuit 35, controller (rake 36), and D/A converter 40. "=7< line is recording in long-time mode f+j raw 1. Broken line is recording in short-time mode The waveforms during playback are indicative.

Now, if we consider the maximum value of the output of the D/A converter 40 mentioned above, the oscillation frequency of the oscillation circuit 17 corresponds to the Raf's speed during playback, so the mode selector 16 is .11 Regardless of which mode is set, when recording in ii2 mode, the maximum value will be a voltage between −'fv2 and ■3 shown in Figure 4, and the long When recording in time mode, the maximum value will be between ■1 and ■2 shown in Figure 4.Here, v3 occurs when the JTP minute magnetic tag is transferred in short time mode. 1) The output voltage of the /A converter 40 is calculated by counting all the signals that occur, and 2 is the output voltage of the /A converter 40 when all the signals generated when the magnetic tape is stopped by 4゛PP in the long-time mode are counted. 1) /
A e:4tf<output voltage of the device 40. Furthermore, Vl
is 1, 11 is 1 (in seven-hour mode, stone 2 'I'
This Vl is the output voltage of the 1)/A converter 40 when counting all the signals that occur when P magnetic tapes are sent 1 times over.

This is determined as appropriate depending on the head widths of the heads 2B, 2C, and 2D.

Therefore, when short-time mode playback is currently being performed by the mode selector 16 and the maximum value of the output voltage of the D/A converter 40 is between ■2 and ■3, the modes match in recording and playback. Therefore, if it is between Vl and ■2, the modes do not match, and if it is 73 or more or vl or less, there is no recording.
This means that recording is performed in a mode different from the short-time mode and long-time mode described above.

On the other hand, when the mode selector 16 is performing long-time mode reproduction, if the maximum value of the force output from the D/A converter 40 is between ■2 and v3, the modes do not match and Vl The transition between vl and vl means that the modes match.

The output of the comparator 36 is supplied to a differentiating circuit 37, and the output of the differentiating circuit 37 is supplied to a sample hold (S/H) circuit 4.
1 as a sampling pulse. Therefore S/
11 circuit 41 resets the D/A converter 40 i'+
The output of fl is ゛v11, and the pressure is S/11 sqb.

The output of the S/I-1 circuit 41 is supplied to comparators 42, 43 and 44 (respectively), and the above-mentioned Vl and V2 obtained by dividing the voltage tB, source '[11', and voltage Vcc with resistors 1 and 1 to 4] ．．
It is compared with Vl.

Now, when a magnetic tape recorded in short-time mode is played back, there are high-level outputs from comparators 42, 43, and 44, and there is no high-level output from inno (-e) 49, so the AND circuit 45 has a high level output, and there is no high level output from the AND circuit 46. There is no output, comparator 44 and I/NO (
- From evening 49 onwards, high level outputs will be sent to iD+. Therefore, in this -J case, the AND circuit 45 has an output of -E level (and the AND circuit 46 has an output of 7% a level).

Terminal 32 is an input terminal for a signal supplied to the mode selector 16. The terminal 32 has a signal input to the mode selector 16. A level signal is supplied.

Therefore, when the magnetic chip recorded in the extra time mode is played back in the extra time mode, there is a high level output from the AND circuit 45, but since a low level signal is supplied to the terminal 32 ((), the AND circuit 47 There is no high level output in both .48 and therefore, there is no high level output in the OR circuit 51.Also, when a magnetic tape recorded in the short time mode is being played back in the short time mode, the OR circuit 51 has no high level output. There is no level output.

On the other hand, when the recording and playback modes do not match, there is an output from the AND circuit 47 or 48 at level 71, so there is also an output from the OR circuit 51 at level 71. The output of the OR circuit 51 is supplied to the capstan/control circuit 12 via the terminal 33, and when the OR circuit 51 has a high level output, the capstan control circuit 12 outputs the capstan 8 via the mode selector 16. Change the transport speed of tape 1 from the long time mode to the short time mode,
Alternatively, the short-time mode may be switched to the long-term mode. When this switching signal (mode error signal) is supplied to the gear stan control circuit 12, the capstan/8 is configured to rotate at the switched transfer speed for a predetermined period (until the servo system becomes stable). are doing.

11-t/,) V'T with the above-mentioned configuration
;' According to it, there are 4 controls for tracking.
If the number i is not recorded at the end of the tape (in addition, the interval between recording tracks can be determined by using the tracking pilot signal superimposed on the video signal, so the TJJK compatible series + Iy at the time of recording) It is possible to play back the tape while it is being transported.Therefore, it is possible to always maintain a good playback condition from the standpoint of the own fb.

It should be noted that the relationship between the recording track shown in FIG. 4 and the rQ: small time trace locus is not necessarily the phase relationship shown in the figure, but whatever the phase relationship, 1) /A conversion. The high volume output of the device 40' is between v2 and Vl when recorded in the 17 hour mode, and between v3 and v2 when recorded in the short time mode.

Further, in the above embodiment, only the case where recording TPY is determined and mode switching is performed during normal playback in long-time mode or short-time mode, but even during variable speed playback, for example, as shown in FIG. The power supply voltage Vcc9n supplied to one end of the resistor kLl is divided into 1/n when performing double speed generation.Vs, iVa/n, Vz y V2
/n, VtyVs/n can be operated in the same way. Also, the oscillator 21
Even if the oscillation frequency is multiplied by 'ftn, the operation can be similarly performed during variable speed reproduction.

<Description of Effects> As explained above using the embodiments, according to the present invention, by effectively utilizing the oscillation means having a plurality of excavated frequencies and the pilot signal recorded superimposed on the recording track, the speed change can be achieved. The information control system provides a control signal for the head shifting means during reproduction and a control signal for the reproduction operation mode designation means according to the recording TP, so that good reproduction can always be performed automatically.
You can get a Haisei Sou@.

[Brief explanation of the drawing]

FIG. 1 shows an example of the present invention, where V 'i' l(
Figure 2 shows the track pattern on the magnetic tape when multiplexing the dual IQ, 4'+n pilot signal for track king onto the video signal and recording it. , FIG. 3 is a diagram showing a specific example of the oscillation circuit in FIG. 1, FIG. 4 is a diagram showing a specific example of the error discrimination circuit in FIG. 1, FIG. 5 (5), ( 131t(C), +1)) are diagrams showing the appearance on the magnetic tape when recording tracks in each mode are generated in each mode, and FIG. 6 is a timing chart showing the operation of the circuit shown in FIG. 4. It is. l denotes magnetic fingers 2A and 2B as recording media. 2C and 2D are heads, 3Δ: (l is a bimorph element as a transition multiplier, respectively) nu・1' Yapstan, 10 is a capstan flywheel, 11 is a flywheel rotation detector, 14 is L1) 15 is an error determination circuit, 16 is a mode selector as a specifying means,
17 is an oscillation circuit as an oscillation means, 18 is a control signal generation circuit, 21 is an oscillator, 22 is a 1i2 frequency divider, 23 is a switch, 34 is an HPF, 35 is an envelope detection circuit 1m,
36 is a comparator, 39 is a counter, 40 is a D/A converter, 41 is a sandal hold circuit, 42.43.44
are comparators, 45, 46, 47, and 48 are AND circuits, 49.50 are inverters, and 51 is an OR circuit. Patent applicant Canon Co., Ltd.

Claims (1)

[Claims] 1) A plurality of 4411 pilot signal sounds are sequentially and repeatedly superimposed at a predetermined period on a track on which a ti-th shadow is formed in a direction intersecting the transport direction.The track is traced by a rotary head from a recording medium on which information signals are repeatedly superimposed at a predetermined period. 1. A device for reproducing an information signal, comprising means for specifying an endogenous operation mode corresponding to the interval between tracks, and selectively reproducing a plurality of types of frequency signals according to the specifying means. an oscillating means for oscillating; a shifting means for displacing at least one of the rotating heads in a direction perpendicular to the rotating surface thereof; and controlling the shifting means using the frequency signal I11; means for obtaining time information corresponding to the repetition period of the pilot signal generated by the rotary head; and means for obtaining time information corresponding to the repetition period of the pilot signal generated by the rotary head; An information signal reproducing device having a means for controlling the specification means.