JPH0376553B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a rotary head type recording device, and more particularly, to a rotating head type recording device that sequentially records a track having a predetermined video area for recording a video signal and a predetermined audio area for recording an audio signal. The present invention relates to a rotary head type recording device that records while forming.

(Description of Prior Art) In recent years, high-density recording has been pursued in the field of magnetic recording, and even in video tape recorders (VTRs), tape running speeds have been lowered to perform even higher-density magnetic recording. There is. For this reason, if audio signals are recorded using a fixed head as in the past, the relative speed cannot be kept high and the reproduced sound quality deteriorates. One solution to this problem is to make the length of the track formed by the rotating head longer than before, and to sequentially record time-base compressed audio signals on the extended portion.

For example, a rotating 2-head helical scan type
In VTRs, magnetic tape has conventionally been wound around a rotating cylinder for more than 180°, but the tape is wrapped around the rotating cylinder for more than (180 + θ)°, and the extra wrapped portion is converted into PCM and time-axis compressed audio signals. A VTR has been devised to record . 1st
The figure shows the tape running system of such a VTR.
2A and 2B are diagrams showing recording trajectories on a magnetic tape by the VTR shown in FIG. 1. In the figure 1
2 is a magnetic tape, 2 is a rotating cylinder, 3 and 4 are heads attached to cylinder 2, 5 is a video area portion of a track formed on tape 1, and 6 is an audio area portion. The video area 5 is the part where the heads 3 and 4 traced the tape at 180° of the rotating cylinder 2, and the audio area 6 is the part where the heads 3 and 4 traced the tape at θ° of the rotating cylinder 2. However, if a guard band is provided between the video area 5 and the audio area 6, the audio area will be shortened accordingly.

When the audio signal is converted to PCM in the audio area and the time axis is compressed in this way, the sound quality is quite high and is comparable to the sound quality of a dedicated audio device that records and plays back analog signals.

(Object of the Invention) This invention was devised against the background of the present invention, and effectively utilizes the above-mentioned rotating head type recording device to perform long-term recording not only as a video recorder but also as an audio-only recorder. The object of the present invention is to provide a rotary head type recording device that is capable of

(Description of Embodiments) Hereinafter, an embodiment in which the present invention is applied to the above-mentioned rotating two-head helical scan type VTR will be described. Note that the citation of the following examples does not limit the scope of the present invention, and the present invention can be modified as appropriate within the scope of the claims.

First, the basic idea of the claimed invention will be explained using the above-mentioned VTR.
This will be explained by taking as an example the case where it is applied to. FIGS. 3A and 3B are diagrams for explaining the basic idea of the present invention. The components shown in FIG. 1 or 2 share the same numbering.

As shown in the figure, when the tape 1 is wound around the rotary cylinder 2 by 210° and used as a VTR, it is exactly the same as before.
A time-compressed audio signal is recorded while heads 3 and 4 move 30° from point A to point B as shown, and a video signal is recorded while heads 3 and 4 move 180° from point B to point H as shown. Record the signal. That is, Figure 3B
A time-axis compressed audio signal is recorded in the area 6a shown in , and a video signal is recorded in the areas 6b to 6g.

Recording of audio signals at this time will be briefly explained. The input audio signal is sampled while the heads 3 and 4 are moving from point B to point H in the figure, and while moving from point H to point A, the signal is processed so that it has a signal form suitable for recording. The heads 3 and 4 moving from point A to point B record in area 6a. FIG. 4 is a timing chart showing how audio signals are processed. In Fig. 4, a is a reference rectangular wave signal of 30 Hz, which is synchronized with the cylinder motor and rises when the head 3 passes point B and falls at 30 Hz when it passes point H.
b shows how the audio signal is processed to be supplied to head 3, and c shows how the audio signal is processed to be supplied to head 4. As shown in the figure, when the audio signal supplied to the head 3 is processed and recorded, the audio signal supplied to the head 4 is sampled. 6a.

The idea of the present invention is that when used as an audio-only device, audio signals are similarly recorded in each of the areas 6b to 6g, and each is made into a separate channel. For example, when recording a time-compressed audio signal in area 6b, it is sampled while the heads 3 and 4 move from point C to point I, is processed while moving from point I to point B, and is sampled while moving from point C to point I. The heads 3 and 4, which are moving from point C to point C, record in area 6b. Audio signals can also be recorded in the areas 6c to 6g by changing the timings of the sampling period, signal processing period, and recording period relative to the rotational phase of the rotary head as described above.

In particular, in the present invention, this is achieved by changing the rotational phase of the rotary head without changing the timings of the sampling period, signal processing period, and recording period.

By adopting this configuration, this device can be
In addition to being used as a VTR, it can also be used as a multi-track audio device for long-term recording. For example, if the recording time for a VTR is 30 minutes, then a 7-track audio recorder can record 210 minutes. Furthermore, the configuration and circuit of the device are similar to those of this type in the past.
Since it can use most of the components used in VTRs, it can also be used as an audio recorder that can record multiple tracks for long periods of time by simply adding a simple circuit.
You can get a device that can also be used as a VCR.

A circuit configuration for realizing the above-described device will be explained below. FIG. 5 is a diagram showing the circuit configuration of a device as an embodiment of the present invention. In FIG. 5, 11 is an audio signal input terminal, 12
is an audio signal output terminal, 13 is a video signal input terminal, 14 is a video signal output terminal, 15
is a low pass filter (LPF), 16 is a sample hold circuit (S/H), 17 is an analog-digital converter (A/D), 18 is a digital-analog converter (D/A), and 19 is a path selector. . Reference numerals 20 and 21 are RAM memories, respectively, and these are referred to as RAM-A and RAM-B, respectively. 22 is an up counter or down counter; 23 is an addressing circuit for interleaving data during data storage; 24 is a parallel-to-serial (P-S) conversion circuit; and 25 is a digital signal processing circuit.
A digital signal recording processing section 26 includes, for example, a well-known error detection word generation circuit, a digital modulation circuit, a synchronization signal pattern addition circuit, and the like.
On the other hand, 27 is a digital signal reproduction processing section, which includes, for example, an error detection circuit, a digital demodulation circuit, a bit synchronization circuit, a synchronization signal pattern separation circuit, and the like.

28 is a recording amplifier for audio signals, 29 is a reproduction amplifier for audio signals, 30 is a recording amplifier for video signals, 31 is a reproduction amplifier for video signals, 3
2 is a head control circuit, 35 is a rotating cylinder, 36 is a recording/reproduction track selection circuit, 37 is a cylinder motor drive circuit, 38 is a control clock generation circuit, and 39 is a crystal oscillator.

The operation will be explained below. First, during recording, an analog audio signal input from the terminal 11 is sampled and held by the S/H 16 via the LPF 15, and quantized by the A/D 17. The quantized digital audio data is sent to RAM-A20 and RAM-B2 via path selector 19.
The data is stored sequentially for every 1 field time, that is, every time the cylinder rotates 180°. To explain this in relation to FIGS. 3A and 3B, for example, if you try to record in area 6a, while the head 3 is moving from point B to point H,
Digital audio data is stored in RAM-A 20, and while the head 4 is moving from point B to point H, digital audio data is stored in RAM-B 21.

While the data is being stored in the RAM-B 21, the data generally stored in the RAM-A 20 is subjected to signal processing by the digital signal processing circuit 25 via the path selector 19. That is, this is done while head 3 is moving from point H to point A, and while head 4 is moving from point B to point G.
Furthermore, during the remaining time that data is stored in RAM-B21, the processed data is stored in RAM-A20.
The signal is then transferred to the P-S conversion shift register 24 via the bus selector 19. Of course RAM-A
While data is stored in RAM-B
The data stored in 21 is subjected to signal processing, and
-S conversion shift register 24.

Furthermore, from this shift register 24, data is transferred to a digital signal recording processing section 25 during recording, where error detection word generation, digital modulation, synchronization signal pattern addition, etc. are performed, and further, via a recording amplifier 28, data is transferred to an area selection circuit The data is transferred to the head 33 or 34 via the head control circuit 32 so that it is recorded in the area specified by 36 with time axis compression.
is supplied to Details of the operations of the head control circuit 32 and area selection circuit 36 will be described later.

Furthermore, when used as a VTR, the audio signal is naturally recorded in the area 6a shown in the third figure, but at this time, the video signal input from the video signal input terminal 13 is processed by the video signal processing circuit 40, and the recording amplifier 30 , are supplied to the head 33 or 34 via the head control circuit 32. Of course, this video signal is provided while each head is moving from point B to point H as shown in FIG. 3A.

Next, the operation during playback will be explained. Head 3
The audio signal of the area selected by the area selection circuit 36 from the reproduction outputs of the signals 3 and 34 is passed through the head control circuit 32, amplified by the reproduction amplifier 31, and then transferred to the digital signal reproduction processing section 27, where it is bit synchronized, Synchronization signal pattern separation, digital demodulation, error detection, etc. are performed. This processing section 2
The signal processed in 7 is subsequently serial-parallel converted by the P-S conversion shift register 24, further processed by the digital signal processing circuit 25 via the bus selector 19, and then sent to the RAM-A 20,
The time axis is expanded and taken out from RAM-B21, returned to analog quantity by D/A18, and S/H1
After being day-glitched at step 6, it is returned to an analog audio signal through LPF 15.

Also, the audio signal is in the area 6a, and the audio signal is in the area 6b~
When a video signal is recorded in area 6g, the area selection circuit 36 naturally selects area 6a. On the other hand, the reproduced video signal obtained by the head control circuit 32 is amplified by the reproduction amplifier 31, and returned to the original signal form by the video signal processing circuit 40.
It is output from the terminal 14.

The timing of the above-mentioned operation is controlled by a control clock generated by the control clock generation circuit 38.

6A and 6B are the area selection circuit 36 in FIG.
3 is a diagram showing a circuit example of the head control circuit 32. FIG. Figure 6A is the area selection circuit, Figure 6B
indicates the head control circuit. Further, FIG. 7 is a timing chart showing waveforms at each part of FIGS. 6a to 6d.

In FIG. 6, 41 is a terminal to which a 30 Hz reference rectangular wave signal (shown in FIG. 7a) obtained from the control clock generation circuit 38 is supplied, 42 is a multi-delay circuit, 43 is a delay time selection switch, and 44
is a phase comparison circuit, 45 is an LPF, 46 is an amplifier,
47 is a terminal to which a phase detection signal of a cylinder motor (not shown) is input, 48 is an output terminal that supplies a control output to the cylinder motor drive circuit 37, 49 is a video signal input terminal from the recording amplifier 30, and 50 is a reproduction amplifier 31 51 is an audio signal input terminal from the recording amplifier 28;
2 is an audio signal output terminal to the reproduction amplifier 29, 53 is an analog switch, 54 and 55 are pulse generation circuits, and 56 is a terminal similar to 41, to which the 30Hz reference rectangular wave signal from the control clock generation circuit 38 is supplied. , 57 and 58 are line selectors, 59 is a terminal connected to head 3, and 60 is a terminal connected to head 4.

The phase detection signal supplied to the terminal 47 in FIG. 6A is a rectangular wave signal (hereinafter referred to as PG) that rises when the head 3 passes point B and falls when it passes point H in FIG. 3A. Suppose there is. In the phase comparator circuit 44, the signal obtained from the terminal 41 is
30Hz reference signal delayed by the time selected by the selection switch 43 (shown in Figure 7 b, b', b'')
and PG are compared in phase. In other words, the rotation of the cylinder motor is controlled so that PG and the output of the selection switch 43 match.

On the other hand, in response to the 30Hz reference signal supplied to the terminal 56, the pulse generation circuits 54 and 55 respectively
and generate pulse signals as shown in d. In other words, the circuit 54 operates at 1/360 just before the rise of the 30Hz reference signal.
1/36 of the reference signal immediately before the falling edge of the reference signal.
Generates a pulse signal that remains at high level for 0 seconds.
The outputs of the generation circuits 54 and 55 are supplied to husband line selectors 57 and 58. line selector 57,
Reference numeral 58 connects the heads 3 and 4 to the audio signal system when the outputs of the generation circuits 54 and 55 are at high level, and connects the heads 3 and 4 to the video signal system when the outputs are at low level.

For example, assume that the selection switch 43 is connected to the terminal 43a, and that the output of the terminal 43a is in phase with the reference signal (as shown in FIG. 7b).
In this case, each head is connected to the audio signal system while the heads 3 and 4 are moving from point A to point B shown in FIG. 3A, and is connected to the video signal system at other times.

Therefore, when the selection switch 43 is connected to the terminal 43a and recording is performed, the audio signal is recorded in the area 6a shown in FIG. 3B, and one field of the video signal is recorded in the areas 6b to 6g. Furthermore, when recording as an audio-only recorder, by turning off the analog switch 53, only the audio signal is recorded in the area 6a. This is of course because the signal processing of each circuit is synchronized with the output of the control clock generation circuit 38. In other words, for example, when the reference signal is at a high level,
Input audio data is being stored in RAM-A20, and when the level is low, input audio data is being stored in RAM-B21. In other words, the reference signal shown in FIG.
The reference signal shown in Figure a is the same.

On the other hand, during playback, while heads 3 and 4 are moving from point A to point B shown in Figure 3A, the playback output of each head is supplied to the audio signal playback system, and at other times, the playback output of each head is supplied to the video signal playback system. is supplied to Of course, when using it as an audio-only recorder, it is desirable to turn off the analog switch 53.

When using this device as a VTR in this way, the selection switch 43 must be connected to the terminal 43a. Therefore, it is desirable to provide a selection switch between a VTR and an audio-only recorder, so that when the VTR is selected, the selection switch 43 is automatically connected to the terminal 43a and the analog switch 53 is turned on.

Next, assuming that the output of terminal 43b is the reference signal delayed by 11/360 seconds (as shown in Figure 7b'),
When the selection switch 43 is connected to the terminal 43b, the audio signal is similarly recorded in the area 6b shown in FIG. 3B and can be reproduced from the area 6b. Other terminals 43c, 43d, 43e of the switch 43,
43f and 43g have reference signals of 10/360 seconds and 9/36 seconds, respectively.
They are delayed by 0 seconds, 8/360 seconds, 7/360 seconds, and 6/360 seconds, and are only used when used as an audio-only recorder. Further, recording and reproduction are performed between the areas 6c, 6d, 6e, 6f, and 6g shown in FIG. 3B, respectively. In Figure 7b'', switch 43 is connected to terminal 4.
The output pulse signal of switch 43 when connected to 3g is shown.

(Explanation of Effects) As explained above, according to the present invention, unlike the conventional rotary head type recording device that sequentially forms tracks having a video area and an audio area, it is possible to record data without changing the processing timing of each signal. By simply adding a simple circuit, this new rotary head type can be used not only as a video recorder, but also as a dedicated audio recorder that can record for long periods of time and provide high sound quality. A recording device is obtained.

[Brief explanation of drawings]

Figure 1 shows the tape running system of a conventional VTR.
Figures 2A and B are diagrams showing the recording trajectory on the magnetic tape by the VTR shown in Figure 1, Figures 3A and B are diagrams showing the basic idea of the present invention, and Figure 4 is the processing of audio signals. FIG. 5 is a diagram showing the circuit configuration of a device as an embodiment of the present invention, and FIGS. 6A and B are circuit examples of the area selection circuit and head control circuit in FIG. 5. The figure shown in FIG. 7 is a timing chart showing waveforms at various parts in FIG. 1 is a magnetic tape, 2 is a rotating cylinder, 3 and 4 are heads, 6a is an audio area, 6
b to 6g are respective areas, 25 is a digital data signal processing circuit, 26 is a digital audio signal recording processing circuit, 32 is a head control circuit, 3
6 is an area selection circuit, 38 is a control clock generation circuit, 40 is a video signal processing circuit, 42 is a multi-delay circuit, 43 is a selection switch, 44 is a phase comparison circuit, and 57 and 58 are line selectors.

Claims (1)

[Claims] 1. A rotary cylinder having a plurality of rotary heads is wound with a tape-shaped recording medium at a predetermined angle, and each has a video area for recording video signals and an audio area for recording audio signals. A device for sequentially forming and recording tracks with the head, the device comprising a first means for supplying a video signal to the head at a predetermined timing, and a second means for supplying an audio signal to the head at a predetermined timing. and phase control means for controlling the rotational phase of the rotary cylinder, a mode for recording the video signal in the video area and recording the audio signal in the audio area, and a mode for recording the audio signal in the video area. and a recording mode in which the audio signal is recorded in the head, and the phase control means switches the rotational phase of the rotary cylinder between these two modes without switching the timing at which the audio signal is supplied to the head by the second means. A rotating head type recording device featuring: