JPH0719326B2 - Rotating head type recording or reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary head type recording or reproducing apparatus, and more particularly, to a headless direction of a head-shaped recording medium by a rotary head tracing diagonally to the longitudinal direction. The present invention relates to a rotary head type recording or reproducing apparatus for recording and reproducing an audio signal or a video signal for each of a plurality of areas arranged at different positions.

<Description of Prior Art> In recent years, in the field of magnetic recording, high-density recording has been pursued, and even in a video tape recorder (VTR), the tape traveling speed is reduced to perform higher-density magnetic recording. There is. Therefore, if an audio signal is recorded by using a fixed head as in the conventional case, the relative speed cannot be made large and the reproduced sound quality is deteriorated. Therefore, as one solution to this problem, there is a method in which the length of the track formed by the rotary head is made longer than in the conventional case, and the time-axis-compressed audio signal is sequentially recorded in the extended portion.

For example, in a rotating 2-head helical scan type VTR, magnetic tape was wound around 180 ° or more on a rotating cylinder in the past, but it was wrapped around the rotating cylinder by (180 + θ) ° or more, and the extra wound portion was converted to PCM. A VTR has been devised which records an audio signal that has been time-compressed. Figure 2 is a diagram showing such a VTR tape running system.
FIG. 3 is a diagram showing a recording track on the magnetic tape by the VTR shown in FIG. In the figure, 1 is a magnetic tape, 2 is a rotating cylinder, 3 and 4 are heads having different azimuth angles attached to the cylinder 2 with a phase difference of 180 °, and 5 is a video area portion of a track formed on the tape 1. Reference numeral 6 is also an audio area portion. The video area 5 is the portion where the heads 3 and 4 trace the tape at 180 ° of the rotating cylinder 2, and the audio area 6 is the portion where the heads 3 and 4 trace the tape at θ ° of the rotating cylinder 2. Also the third
In the figure, f _{1 to} f ₄ indicate the frequencies of the tracking pilot signal superimposed on each track by the well-known four-frequency method, and the relationship between the frequencies is (f ₂ −f ₁ = f ₃ −f ₄ ≈f _H , f ₄
−f ₂ ≈ 2f _H. However, f _H indicates the horizontal scanning frequency of the video signal.

In this way, the sound quality of the audio signal reproduced into PCM in the audio area and compressed on the time axis is considerably high, and is comparable to the sound quality of the dedicated audio device which records and reproduces the analog signal.

On the other hand, it has been proposed to record another audio signal in the video area 5 in the above-mentioned inferior VTR. That is, when θ = 36, for example, if the rotary head rotates by 180 °, five other audio regions such as 6 are provided. Then, by recording the time-compressed audio signals in each area independently, an audio dedicated tape recorder capable of recording a total of 6 channels of audio signals can be obtained.

The tape recorder will be briefly described below. FIG. 4 is a diagram showing a tape running system of the above-mentioned tape recorder, and FIG. 5 is a diagram showing recording loci on the tape by this tape recorder. Incidentally, the numbering is shared with FIG. 2 and FIG.

In FIG. 5, CH1 to CH6 are the periods during which the head 3 or head 4 traces A to B, B to C, C to D, D to E, E to F, and F to G in FIG. 3, respectively. This is the area where the audio signal is recorded. It is possible to separately record audio signals in each area, and so-called azimuth overwriting is performed in each area, but the tracks in each area CH1 to CH6 do not have to be on the same straight line. The pilot signals for tracking control are recorded in each area, but it is assumed that the pilot signals for each area are recorded at a predetermined rotation (f ₁ → f ₂ → f ₃ → f ₄ ). There is no correlation to.

Areas indicated by CH1 to CH3 are recorded and reproduced when the tape 1 is running at a predetermined speed in a direction shown by an arrow 7 in FIG. 3, and areas shown by CH4 to CH6 are also run in a direction shown by an arrow 9. It is recorded and reproduced when Therefore, as shown in FIG. 5, the inclination of each track in the area shown in CH1 to CH3 and CH4 to C
The slope of each track in the area indicated by H6 is slightly different. However, the difference in relative speed at this time is not a problem because the tape 1 travels much less than the heads 3 and 4 rotate.

FIG. 6 is a time chart of recording / reproduction of the tape recorder as described above. In the figure, (a) is a phase detection pulse (hereinafter referred to as PG) generated in synchronization with the rotation of the cylinder 2, and repeats "high level" (H) and "low level (L)" in 1/60 seconds.
It is a 30Hz square wave. Further, (b) is a PG having a polarity opposite to that of PG (a). Here, PG (a) is H while the head 3 is rotating from B to G in FIG. 4, and PG (b) is the same as head 4 is B.
It is assumed to be H during the rotation from G to G.

FIG. 6 (c) is a pulse for reading data obtained from PG (a), in order to sample the audio signal every other field for the period corresponding to one field (1/60 seconds) of the video signal. belongs to. FIG. 6 (d) shows a signal processing period H for adding error correction redundancy code or the like to the sampled audio data for one field using RAM or the like.
Indicate. FIG. 6 (e) shows a data recording period, and shows the timing of recording the recording data obtained by the above-described signal processing on the tape 1.

For example, if the signal flow is tracked in time using FIG. 6, t1
The data sampled during the period from t3 to t3 (while the head 3 is moving from B to G) is subjected to signal processing at t3 to t5 (head 3 is G to A), and t5 to t6 (head 3 is A to B). Will be recorded during the period. That is, it is recorded in the CH1 area of FIG. 5 by the head 3. On the other hand, the data sampled while PG (b) is H is processed at the same timing,
Is recorded in the CH1 area by.

FIG. 6 (f) shows a PG in which PG (a) is phased by a predetermined phase (here, 36 ° for one area). Hereinafter, a case where an audio signal is recorded by PG (f) and a PG (not shown) having an opposite characteristic will be described. The data sampled from t2 to t4 in FIG. 6 is signal-processed according to the signal shown in FIG. 6 (g) during t4 to t6 and recorded according to the signal shown in FIG. 5 (h) during the period from t6 to t7. . That is, the head 3 records in the area indicated by CH2 in FIG. 5 while the head 3 traces B to C. The data sampled in the period of t4 to t7 in synchronization is recorded by the head 4 in the area indicated by CH2.

Next, the operation of reproducing the signal recorded in the area indicated by CH2 will be described.

Data reading from the tape 1 by the head 3 is performed at t6 to t7 (t1 to t2 are the same) in accordance with the signal shown in FIG. 6 (h), and t7 to t8 (t2 in accordance with the signal shown in FIG. 6 (i). The signal processing opposite to that at the time of recording is performed from ~ t3). That is, error correction is performed during this period, and then t8 is applied in accordance with the signal shown in FIG. 6 (j).
The playback audio signal is output at ~ t9 (t3 ~ t6). Of course, the reproducing operation by the head 4 is performed with a phase difference of 180 ° from the above-mentioned operation, so that a continuous reproducing audio signal can be obtained.

It is needless to say that the PG (a) is transferred by n × 36 ° for the other areas CH3 to CH6, and the above-mentioned recording / reproducing operation is performed based on this, and this is also the tape running direction. Does not depend on

In this way, the VTR can be used as an audio-only device for multiple channels.

<Problems to be Solved by the Invention> In the above-mentioned device, it is possible to record an audio signal for an extremely long time, but on the other hand, if the recording situation is not grasped, there is a high possibility of erroneous operation. That is, in addition to the recorded and unrecorded portions of the audio signal for each channel, a video signal may be recorded on CH2 to CH6, and there is a remaining portion of the video signal that remains unerased. Therefore, it is difficult to accurately determine the recording status.

Moreover, if a video signal is erroneously recorded on such a recording medium, all audio signals from CH2 to CH5 will be erased. Moreover, if the audio signal is recorded even on a channel of CH2 to CH5 on the medium on which the video signal is recorded, the video signal itself becomes invalid this time.

In view of the background as described above, it is an object of the present invention to provide a rotary head type recording or reproducing apparatus which allows the recording conditions of all areas to be grasped quickly and which is extremely easy to use.

<Means for Solving the Problems> In the present invention, in view of the above-mentioned problems, first detecting means for detecting the presence or absence of a video signal in the output signal of the rotary head, and an audio signal in the output signal of the rotary head The second detecting means for detecting the presence / absence of the presence and the detecting means of the first detecting means and the detecting means of the second detecting means are respectively extracted at timings corresponding to a plurality of areas, and a video signal is recorded for each area. A determination means for determining whether the audio signal is recorded or not recorded is provided.

<Operation> By using the output of the above-mentioned discrimination means, it becomes possible to quickly discriminate the recording status of the audio signal and the video signal in each area.

<Embodiment> FIG. 1 is a diagram showing a schematic configuration of a tape recorder as an embodiment of the present invention. In FIG. 1, the same components as those in FIGS. 2 to 5 are designated by the same reference numerals.

PG obtained from the rotation detector 11 of the rotating cylinder 2 is supplied to the cylinder motor control circuit 15 to rotate the cylinder 2 at a predetermined rotation speed and a predetermined rotation phase. Reference numeral 12 is a rotation detector of the flywheel 14 of the capstan 13, and the output of the rotation detector 12 is supplied to a capstan motor control circuit 25, which controls the capstan 13 to have a predetermined rotation speed during recording.

On the other hand, the above-mentioned PG is supplied to the window pulse generation circuit 16. Figure 7 shows window pulse and gate pulse PG
3 is a timing chart for explaining a phase relationship with respect to.

FIG. 7 (a) is a PG, and the head 3 is B in FIG.
It becomes high level while moving from point G to point G. Fig. 7 (b)
(G) is a window pulse which shows the recording / reproducing timing of each area | region CH1-CH6, respectively. In FIG. 7, the solid line is for the head 3 and the dotted line is for the head 4.

By operating the operation unit 18 manually, operation modes such as recording and reproduction, and an area to be recorded and reproduced are designated. This data is supplied to the system controller 27,
Controls each part of the device. The area designating circuit 19 supplies the area designating data to the gate pulse generating circuit 17 to obtain a desired gate pulse. If the recording or reproduction of the video signal is performed by the operation unit 18, the output of the system controller 27 causes
The area designating circuit 19 automatically designates CH1.

The control gate pulse of the gate circuit 20 is selectively supplied based on the area designation data for each of the head 3 and the head 4 as shown in the above-mentioned window pulse (FIGS. 7B to 7G). To be done. If the area shown in CH2 in FIG. 5 is designated, the gate circuit 20 is controlled by the window pulse shown in FIG. 7 (c).

During recording, the analog audio signal input from the terminal 21i is supplied to the PCM audio signal processing circuit 22,
In step 2, the signal is sampled at the above-mentioned timing related to the window pulse (c), converted into digital data, and then subjected to the above-mentioned signal processing. The recording audio data thus obtained is added by the adder 24 to the tracking pilot signal generated by the rotation of f ₁ → f ₂ → f ₃ → f ₄ from the pilot signal generating circuit 23 for each field. The output of the adder 24 is appropriately gated by the gate circuit 20 as described above, and is written in the area CH2 by the heads 3 and 4.

During reproduction, the reproduction signals of the heads 3 and 4 are also supplied to the low pulse filter (LPE) 25 and the PCM audio circuit 22 via the gate circuit 20 by the window pulse (c). PCM
Error correction in contrast to the recording in the audio circuit 22, time axis expansion, digital - signal processing of the analog conversion, etc. is performed, and outputs from the terminals 21 ₀ reproduced analog audio signal.

The ATF circuit 26 is a circuit for obtaining a tracking error signal according to a well-known four-frequency system. The reproduced tracking pilot signal and the pilot signal generated by the pilot signal generating circuit 23 at the same rotation as during recording are used. It is well known to use. However, in this case,
Since tracking is performed for the area designated by the area designating circuit 19, the tracking error signal must be sampled and held within the period in which the heads 3 and 4 trace the designated area. Incidentally, when the video signal is simultaneously recorded and reproduced, the tracking error signal is obtained by the conventional method.

The tracking error signal thus obtained is supplied to the motor control circuit 15, and the running of the tape L during reproduction is controlled via the capstan 13 to perform tracking control.

The recording / reproducing of the video signal when the recording / reproducing of the video signal is instructed will be described below. The video signal input from the terminal 28i is subjected to known signal processing in the video signal processing circuit 29, added with the tracking pilot signal in the adder 31, and recorded via the post-gate circuit 30. The gate circuit 30 is controlled by the PG, and the video signal is
It is recorded continuously in sequence at 3 and 4. The video signals reproduced from the heads 3 and 4 are converted into continuous signals by the gate circuit 30 and input to the video signal processing circuit 29. Video signal processing circuit 29
Then, the reproduced video signal is returned to the original signal form. At the same time, the reproduction pilot signal is supplied to the ATF circuit 26 to obtain a tracking error signal. Since this tracking error signal is a continuous signal, it is not necessary to sample and hold it and is supplied to the capstan motor control circuit via the LPF.

Reference numeral 35 is a recording state discrimination circuit which constitutes the discrimination means in the present invention. The circuit 35 uses the reproduction output of the head 3 to record an audio signal or a video signal in each area. It is discriminating whether it is unrecorded.

The recording state determination circuit will be described in detail below. FIG. 8 is a diagram showing an example of a specific circuit configuration of the recording state determination circuit.

Reference numeral 40 is a terminal to which the reproduction output signal of the head 3 is supplied, and this signal is supplied to the LPF 42 and the BPF 41. The BPF 41 is for separating the color sub-carrier component (fsc) of the recorded video signal. The separated color sub-carrier is detected by the detection circuit 43 and then compared with a predetermined voltage (Vth2) by the comparison circuit 45. Be compared. Therefore, the output of the comparison circuit 45 becomes high level (H) when the head 3 traces the portion where the video signal is recorded.

On the other hand, 42 is an LPF for separating all the RF signal components in the reproduction output signal of the head 3, and the similarly separated RF signal is detected by the detection circuit 44 and then compared with Vth1 by the comparison circuit 46. It Along with this, the output of the comparison circuit 46 becomes high level when the head 3 traces the portion where the video signal or audio signal is recorded. The output of the comparison circuit 45 is supplied to the AND gate 48 via the inverter 47, and the AND of the output of the comparison circuit 46 is obtained. As a result, the output of the AND gate 48 becomes H when the head 3 traces the portion where the audio signal is recorded by the head 3.

That is, the signal indicated by A in the figure is H when the head 3 is reproducing an audio signal, and the signal indicated by V is H when the head 3 is reproducing a video signal. From which region the audio signal and the video signal are reproduced can be discriminated by using the window pulse described above.

Window gate corresponding to CH1 to CH6 is AND gate 51
When a reproduction audio signal is obtained from a certain area, the AND gate corresponding to that area outputs H once every one rotation of the rotary head 3. The other
The window pulse corresponding to CH2 to CH6 is AND gate 62
Similarly, when a reproduced video signal is obtained from a certain area, the AND gate corresponding to that area outputs H once every one rotation of the rotating head. It is assumed here that no video signal is recorded or reproduced on CH1.

Mono-multi (MM) 71-76 and 82-86 are AND gates 51
.About.56, 62 to 66 for holding the output signals, and the holding period of H can be retriggered in the rotation cycle of the head 3 or more. Therefore, the area in which the audio signal is recorded in CH1 to CH6 can be identified by the terminals H1 to CH6 in FIG. 8 becoming H. The area where the video signals of CH2 to CH6 are recorded can be identified by looking at the outputs of MM82 to 86, but since the video signals are valid only when they are recorded to all of CH2 to CH6, these MM82 Whether or not a valid video signal is recorded can be determined by the logical product of the outputs of ~ 86. That is, when the output of the AND gate 49 is H, a valid video signal is recorded.

The outputs shown on CH1 to CH6 and VIDEO in FIG. 8 are supplied to the display 36 in FIG. FIG. 9 is a view showing a concrete example of the display 36. In FIG. 9, 50 is a display board, and 91 to 96 are eighth boards.
Reference numeral 97 denotes a display element which indicates that the output shown by CH1 to CH6 is H, and 97 is a display element which indicates that the output shown in VIDEO of FIG. 8 is H.

When such a recording status determination of each area is not performed, this display functions as a so-called digital level meter. That is, the display elements 91 to 96 are driven based on the reproduction audio signal level. Since this level meter is well known, detailed description thereof will be omitted.

The display element 57 is turned on when the display elements 91 to 96 are used as a level meter, and the display element 58 is turned on when the recording state of the audio signal is indicated.

According to the apparatus as described above, it is possible to quickly determine whether the audio signal is recorded, the video signal is recorded, or not recorded for each of the six areas. Further, by displaying according to this, it becomes extremely convenient for the user. Further, as shown in the preferred embodiment, if the recording status discrimination display and the level meter display are performed by using the same display element, the display unit is not complicated and the device is not enlarged.

FIG. 10 and FIG. 11 are diagrams showing a partially modified example of the configuration of the recording state discrimination circuit. In the example of FIGS. 10 and 11, it is premised that a PCM audio signal is recorded with a pilot signal having a frequency f ₅ other than the tracking pilot signal (TPS) of f _{1 to} f ₄ described above. 42 'is a BPF for separating the f ₅ component, and 41' is a BPF for separating the TPS (f _{1 to} f ₄ ). The detection circuits 43 ', 44' and the comparison circuits 45 ', 46' perform the same operations as those shown by 43, 44, 45, 46 in FIG. 8, and Vth3, Vt
h4 is the comparison level in the comparison circuits 46 'and 45', respectively.

Accordingly, the comparison circuit 46 'outputs H when the head 3 is reproducing an audio signal, and the comparison circuit 45' outputs H when the head 3 is reproducing an audio signal or a video signal. . The output of the comparison circuit 46 'is led to the AND gate 48' through the inverter 47 ', and the output of the AND gate 48' becomes H when the head 3 is reproducing the video signal. In this way, the same signals as A and V in FIG. 8 are obtained.

In FIG. 11, the same components as those in FIG. 8 or 10 are designated by the same reference numerals. It is unnecessary to explain that the same signal as the above-mentioned A is obtained from the comparison circuit 45 and the above-mentioned A from the comparison circuit 46 '.
Therefore, it goes without saying that the same effect as described above can be obtained with the configuration shown in FIG. 10 or FIG.

In the above embodiment, the display is performed only when the video signal is recorded in an effective form for the convenience of the user, but the same effect may be obtained by displaying each area.

It is also possible to configure such that an operation such as prohibiting recording is performed without displaying.

<Effects of the Invention> As described above, according to the present invention, the audio of each of a plurality of regions arranged at mutually different positions in the tracing direction of the rotary head that obliquely traces the longitudinal direction of the tape-shaped recording medium. Since the recording status of the signal and the video signal can be judged, a rotary head type recording or reproducing apparatus which is extremely easy to use is obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic structure of a tape recorder as one embodiment of the present invention, FIG. 2 is a diagram showing a conventional VTR tape running system, and FIG. 3 is a VTR magnetic tape shown in FIG. FIG. 4 is a diagram showing a recording track of a multi-channel tape recorder, FIG. 5 is a diagram showing a recording track on a magnetic tape by the tape recorder shown in FIG. 4, and FIG. Recording / playback time chart of the tape recorder shown in FIG. 4, FIG. 7 is a timing chart for explaining the phase relation of the window pulse to PG, and FIG. 8 is a specific example of the recording state discrimination circuit in FIG. FIG. 9 is a diagram showing a specific example of the display unit in FIG. 1, and FIGS. 10 and 11 are diagrams showing partially modified examples of the configuration of the recording state discrimination circuit of FIG. 8, respectively. 1 is a magnetic tape as a recording medium, 3 and 4 are rotating heads, 16 is a window pulse generating circuit as a timing signal, 22 is a PCM audio signal processing circuit, 29 is a deo signal processing circuit, and 35 is a discriminating means. Recording state determination circuit,
36 is a display, and CH1 to CH6 are regions extending in the longitudinal direction.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hirohisa Takahashi 770 Shimonoge, Takatsu-ku, Kawasaki City, Kanagawa Prefecture, Tamagawa Plant, Canon Inc. (72) Kenichi Nagasawa 770 Shimonoge, Takatsu-ku, Kawasaki-shi, Kanagawa Canon Inc. Company Tamagawa Works (56) References JP-A-59-221854 (JP, A) Actual development: S58-35117 (JP, U)

Claims (1)

[Claims] 1. A rotary head for recording and reproducing a signal while tracing in a direction oblique to a longitudinal direction of a tape-shaped recording medium, and a plurality of areas arranged at positions different from each other in a tracing direction of the rotary head. A rotary head type recording or reproducing apparatus which selectively records and reproduces a video signal or an audio signal in any of the areas therein, and detects the presence or absence of a video signal in the output signal of the rotary head. First detecting means; second detecting means for detecting the presence / absence of an audio signal in the output signal of the rotary head; and the first detecting means and the second detecting means at timings corresponding to the plurality of regions. A detection means for extracting each of the detection outputs of, and determining, for each area, whether a video signal is recorded, an audio signal is recorded, or an unrecorded state, A rotary head type recording or reproducing device comprising.